Sample records for experimental studies involve

  1. Student Involvement in Learning and School Achievement.

    ERIC Educational Resources Information Center

    Anderson, Lorin W.

    The purpose of the study was to investigate the relationship between selected student characteristics, student involvement in learning, and achievement. Both naturalistic (n = 28, 27) and experimental studies were conducted. In the experimental study, two classes (n = 29, 26) learned a sequence of matrix arithmetic by mastery learning strategies.…

  2. AN EXPERIMENTAL STUDY OF THE RELATIONSHIP OF FILM MOVEMENT AND EMOTIONAL RESPONSE, AND ITS EFFECT ON LEARNING AND ATTITUDE FORMATION.

    ERIC Educational Resources Information Center

    MILLER, WILLIAM CHARLES, III

    THIS EXPERIMENTAL STUDY EXAMINED THE HYPOTHESES THAT FILM MOTION INCREASES AUDIENCE EMOTIONAL INVOLVEMENT, INCREASES POSITIVE ATTITUDE RESPONSE TO THE FILM AND DOES NOT AFFECT AUDIENCE INFORMATION RETENTION. OTHER HYPOTHESES WERE THAT THE GALVANIC SKIN RESPONSE (GSR) IS USEFUL FOR EVALUATING FILM AUDIENCE EMOTIONAL INVOLVEMENT, THAT AUDIENCE…

  3. Experimental study of combustion processes involved in hypergolic propellant coaxial injector operation

    NASA Astrophysics Data System (ADS)

    Habiballah, M.; Dubois, I.; Gicquel, P.; Foucaud, R.

    1992-07-01

    The first results are presented of an experimental research program to understand the operation of a coaxial injector using hypergolic propellants. Mechanisms and processes involved in coaxial injector operation are identified for a two-plate injector and a coaxial injector. The usefulness of backlight cinematography and laser sheet visualization in the study of coaxial injector operation is examined. A review of the literature on injector elements using highly reactive hypergolic propellants is presented along with an analysis of fundamental mechanisms involved in these propellants.

  4. Using an experimental model for the study of therapeutic touch.

    PubMed

    dos Santos, Daniella Soares; Marta, Ilda Estéfani Ribeiro; Cárnio, Evelin Capellari; de Quadros, Andreza Urba; Cunha, Thiago Mattar; de Carvalho, Emilia Campos

    2013-02-01

    to verify whether the Paw Edema Model can be used in investigations about the effects of Therapeutic Touch on inflammation by measuring the variables pain, edema and neutrophil migration. this is a pilot and experimental study, involving ten male mice of the same genetic strain and divided into experimental and control group, submitted to the chemical induction of local inflammation in the right back paw. The experimental group received a daily administration of Therapeutic Touch for 15 minutes during three days. the data showed statistically significant differences in the nociceptive threshold and in the paw circumference of the animals from the experimental group on the second day of the experiment. the experiment model involving animals can contribute to study the effects of Therapeutic Touch on inflammation, and adjustments are suggested in the treatment duration, number of sessions and experiment duration.

  5. A Dyadic Interactive Approach to the Study of Leader Behavior

    DTIC Science & Technology

    1975-07-01

    supervisors and workers in a bogus greeting card company performed experimental tasks involving construction of " origami " cranes. The following variables...comprised of a supervisor and three workers who, in turn, were assigned the task of producing " origami " paper cranes and were paid on a piece-rate basis...behaviors as he inter- acted with his followers. Experimental Task The experimental task involved the construction of " origami " cranes from sheets of

  6. Relationship with BSE (Mad Cow Disease)

    MedlinePlus

    ... consistent with known incubation periods for CJD. An experimental study reported in June 1996 showed that three ... of CJD (Nature 1996;383:685-90). An experimental study involving inoculation of a panel of inbred ...

  7. Effects of mothers involved in dental health program for their children.

    PubMed

    Choi, Hye Seon; Ahn, Hye Young

    2012-12-01

    The purpose of this study was to identify the effects of mothers' involvement in a dental health program for their elementary school children. This study was a non-equivalent control group pre-post test design in which knowledge and behaviors related to dental health, perceived benefits and barriers, self-efficacy and plaque control scores were compared between the experimental group (n=26) for whom the dental health program included the direct involvement of the mothers, and the control group (n=24) for whom knowledge related to dental health was provided through brochures. Scores for the experimental group in which the mothers were involved in the dental health program were significantly higher for knowledge, behaviors in dental health, self-efficacy and plaque control compared to the control group. Results of this study suggest that mothers involvement in the dental health program is effective in reinforcing dental health enhancing behavior in elementary school children.

  8. Assessing the Relationship between Different Types of Student Feedback and the Quality of Revised Writing

    ERIC Educational Resources Information Center

    Diab, Nuwar Mawlawi

    2011-01-01

    This paper reports on a quasi-experimental study comparing the effects of peer-editing to self-editing on improving students' revised drafts. The study involved two intact classes (experimental and control groups) of an English course. The experimental group practiced peer-editing while the control group engaged in self-editing. After receiving…

  9. Ischemic compression and joint mobilisation for the treatment of nonspecific myofascial foot pain: findings from two quasi-experimental before-and-after studies.

    PubMed

    Hains, Guy; Boucher, Pierre B; Lamy, Anne-Marie

    2015-03-01

    The aim of this study was to evaluate the efficacy of myofascial therapy involving ischemic compression on trigger points in combination with mobilization therapy on patients with chronic nonspecific foot pain. Two quasi-experimental before-and-after studies involving two different baseline states. Foot pain patients at a private clinic were divided into two separate cohorts: A, custom orthotic users; and B, non-users. In Study A, 31 users received 15 experimental treatments consisting of ischemic compressions on trigger points and mobilization of articulations through the foot immediately after study enrollment. In study B, ten non-users were prescribed a soft prefabricated insole and were monitored for five weeks before subsequently receiving 15 experimental treatments after the initial five-week delay. The Foot Function Index (FFI) and patients' perceived improvement score (PIS) on a scale from 0% to 100%. The Study A group (n=31) maintained a significant reduction in the FFI at all three follow-up evaluations. Mean improvement from baseline in FFI was 47%, 49% and 56% at 0, 1 and 6 months, respectively, post-treatment. Mean PIS was 58%, 57%, and 58%, again at 0, 1 and 6 months post-treatment. For the Study B group, mean improvement in FFI was only 19% after the monitoring period, and 64% after the experimental treatment period. Mean PIS was 31% after monitoring, and 78% after experimental treatment. In repeated measures analyses, experimental treatment was associated with a significant main effect in both of these before-and after studies (all P values<0.01). Combined treatment involving ischemic compression and joint mobilization for chronic foot pain is associated with significant improvements in functional and self-perceived improvement immediately and at up to six-months post-treatment. Further validation of this treatment approach within a randomized controlled trial is needed.

  10. Learning with Concept and Knowledge Maps: A Meta-Analysis

    ERIC Educational Resources Information Center

    Nesbit, John C.; Adesope, Olusola O.

    2006-01-01

    This meta-analysis reviews experimental and quasi-experimental studies in which students learned by constructing, modifying, or viewing node-link diagrams. Following an exhaustive search for studies meeting specified design criteria, 67 standardized mean difference effect sizes were extracted from 55 studies involving 5,818 participants. Students…

  11. Examining the Relationship between Psychosocial and Behavioral Proxies for Future Consumption Behavior: Self-Reported Impact and Bidding Behavior in an Experimental Auction Study on Cigarette Labeling

    ERIC Educational Resources Information Center

    Rousu, Matthew C.; Thrasher, James F.

    2014-01-01

    Experimental and observational research often involves asking consumers to self-report the impact of some proposed option. Because self-reported responses involve no consequence to the respondent for falsely revealing how he or she feels about an issue, self-reports may be subject to social desirability and other influences that bias responses in…

  12. 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...

  13. Parent Involvement Affects Children's Cognitive Growth.

    ERIC Educational Resources Information Center

    Irvine, David J.; And Others

    As part of a longitudinal study of the New York State Experimental Prekindergarten Program, the effect of degree of parental involvement in the program on children's cognitive development was examined. Parent involvement included employment in the program, school visits, home visits by school personnel, group meetings, and incidental contacts such…

  14. Analyzing Data from a Pretest-Posttest Control Group Design: The Importance of Statistical Assumptions

    ERIC Educational Resources Information Center

    Zientek, Linda; Nimon, Kim; Hammack-Brown, Bryn

    2016-01-01

    Purpose: Among the gold standards in human resource development (HRD) research are studies that test theoretically developed hypotheses and use experimental designs. A somewhat typical experimental design would involve collecting pretest and posttest data on individuals assigned to a control or experimental group. Data from such a design that…

  15. Bioinformatic prediction of leader genes in human periodontitis.

    PubMed

    Covani, Ugo; Marconcini, Simone; Giacomelli, Luca; Sivozhelevov, Victor; Barone, Antonio; Nicolini, Claudio

    2008-10-01

    Genes involved in different biologic processes form complex interaction networks. However, only a few have a high number of interactions with the other genes in the network. In previous bioinformatics and experimental studies concerning the T lymphocyte cell cycle, these genes were identified and termed "leader genes." In this work, genes involved in human periodontitis were tentatively identified and ranked according to their number of interactions to obtain a preliminary, broader view of molecular mechanisms of periodontitis and plan targeted experimentation. Genes were identified with interrelated queries of several databases. The interactions among these genes were mapped and given a significance score. The weighted number of links (weighted sum of scores for every interaction in which the given gene is involved) was calculated for each gene. Genes were clustered according to this parameter. The genes in the highest cluster were termed leader genes. Sixty-one genes involved or potentially involved in periodontitis were identified. Only five were identified as leader genes, whereas 12 others were ranked in an immediately lower cluster. For 10 of 17 genes there is evidence of involvement in periodontitis; seven new genes that are potentially involved in this disease were identified. The involvement in periodontitis has been completely established for only two leader genes. We applied a validated bioinformatics algorithm to increase our knowledge of molecular mechanisms of periodontitis. Even with the limitations of this ab initio analysis, this theoretical study can suggest ad hoc experimentation targeted on significant genes and, therefore, simpler than mass-scale molecular genomics. Moreover, the identification of leader genes might suggest new potential risk factors and therapeutic targets.

  16. Visual Literacy and the Integration of Parametric Modeling in the Problem-Based Curriculum

    ERIC Educational Resources Information Center

    Assenmacher, Matthew Benedict

    2013-01-01

    This quasi-experimental study investigated the application of visual literacy skills in the form of parametric modeling software in relation to traditional forms of sketching. The study included two groups of high school technical design students. The control and experimental groups involved in the study consisted of two randomly selected groups…

  17. Do cooperative learning and family involvement improve variables linked to academic performance?

    PubMed

    Santos Rego, Miguel A; Ferraces Otero, María J; Godas Otero, Agustín; Lorenzo Moledo, María M

    2018-05-01

    One of the most serious problems in the Spanish education system is the high percentage of school failure in Compulsory Secondary Education. The aim of this study is to analyze the influence of a socio-educational program based on cooperative learning and family involvement on a series of variables related to academic performance, paying particular attention to the differences between retained and non-retained students. A two-group quasi-experimental design incorporating pre-testing and post-testing was used. The study involved 146 students in the experimental group and 123 in the control group, 8 teachers, and 89 parents or other family members. The program was observed to have a positive effect on self-image, study habits, satisfaction with the subject, maternal support and control, and opinions about the school. In addition, the results for non-retained students are better. Cooperative work and family involvement in education affect the variables which research links to improving school performance.

  18. 16 CFR 1702.10 - Human experimental data involving the testing of human subjects.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 16 Commercial Practices 2 2011-01-01 2011-01-01 false Human experimental data involving the testing of human subjects. 1702.10 Section 1702.10 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION... PACKAGING ACT REQUIREMENTS; PETITION PROCEDURES AND REQUIREMENTS § 1702.10 Human experimental data involving...

  19. 16 CFR 1702.10 - Human experimental data involving the testing of human subjects.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 16 Commercial Practices 2 2012-01-01 2012-01-01 false Human experimental data involving the testing of human subjects. 1702.10 Section 1702.10 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION... PACKAGING ACT REQUIREMENTS; PETITION PROCEDURES AND REQUIREMENTS § 1702.10 Human experimental data involving...

  20. 16 CFR 1702.10 - Human experimental data involving the testing of human subjects.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 16 Commercial Practices 2 2014-01-01 2014-01-01 false Human experimental data involving the testing of human subjects. 1702.10 Section 1702.10 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION... PACKAGING ACT REQUIREMENTS; PETITION PROCEDURES AND REQUIREMENTS § 1702.10 Human experimental data involving...

  1. 16 CFR 1702.10 - Human experimental data involving the testing of human subjects.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 16 Commercial Practices 2 2010-01-01 2010-01-01 false Human experimental data involving the testing of human subjects. 1702.10 Section 1702.10 Commercial Practices CONSUMER PRODUCT SAFETY COMMISSION... PACKAGING ACT REQUIREMENTS; PETITION PROCEDURES AND REQUIREMENTS § 1702.10 Human experimental data involving...

  2. Strategies Training in the Teaching of Reading Comprehension for EFL Learners in Indonesia

    ERIC Educational Resources Information Center

    Mistar, Junaidi; Zuhairi, Alfan; Yanti, Nofita

    2016-01-01

    This study investigated the effect of reading strategies training on the students' literal and inferential reading comprehension. The training involved three concrete strategies: predicting, text mapping, and summarizing. To achieve the purpose of this study, a quasi experimental design was selected with the experimental group being given reading…

  3. Tech versus the Human Touch: Teacher Affect Is More Effective.

    ERIC Educational Resources Information Center

    Perry, Alan

    2003-01-01

    An experimental group studied Macbeth in an independent, constructivist setting using multimedia; the control group studied traditionally. Eleven of 23 experimental students and 2 of 21 in the traditional class failed. In an experiment with Hamlet, the results were reversed. Students were most successful when the teacher was actively involved,…

  4. 48 CFR 27.405-1 - Special works.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ..., books, studies, surveys, or similar documents that do not involve research, development, or experimental...; (3) Surveys of Government establishments; (4) Works pertaining to the instruction or guidance of... that resulting from research, development, or experimental work performed by the contractor), the early...

  5. 48 CFR 27.405-1 - Special works.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ..., books, studies, surveys, or similar documents that do not involve research, development, or experimental...; (3) Surveys of Government establishments; (4) Works pertaining to the instruction or guidance of... that resulting from research, development, or experimental work performed by the contractor), the early...

  6. 48 CFR 27.405-1 - Special works.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ..., books, studies, surveys, or similar documents that do not involve research, development, or experimental...; (3) Surveys of Government establishments; (4) Works pertaining to the instruction or guidance of... that resulting from research, development, or experimental work performed by the contractor), the early...

  7. 48 CFR 27.405-1 - Special works.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ..., books, studies, surveys, or similar documents that do not involve research, development, or experimental...; (3) Surveys of Government establishments; (4) Works pertaining to the instruction or guidance of... that resulting from research, development, or experimental work performed by the contractor), the early...

  8. 48 CFR 27.405-1 - Special works.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ..., books, studies, surveys, or similar documents that do not involve research, development, or experimental...; (3) Surveys of Government establishments; (4) Works pertaining to the instruction or guidance of... that resulting from research, development, or experimental work performed by the contractor), the early...

  9. Developing students’ learning achievement and experimental skills on buoyancy and the involvement of Newton’s third law through experimental sets

    NASA Astrophysics Data System (ADS)

    Chokchai, Jaewijarn; Khanti, Toedtanya; Sura, Wuttiprom

    2017-09-01

    The purposes of this research were: to construct packages of operations on buoyancy and the involvement of Newton’s third law, to enhance achievement score of students on buoyancy and the involvement of Newton’s third law, to enhance experimental skills on buoyancy and the involvement of Newton’s third law and to evaluate students’ attitude towards the packages of operations on buoyancy and the involvement of Newton’s third law using inquiry method. The samples were 42 grade 11 students in academic year 2016 at Hatyaiwittayalai School, Hatyai, Songkhla. The research method was one group pretest-posttest design. The research tools consisted of experimental set on buoyancy and the involvement of Newton’s third law, the learning achievement test on buoyancy and the involvement of Newton’s third law and the students’ attitude questionnaires. The experimental skills of most students was in a good level . The satisfaction of most students was in a good level. The research showed the learning achievement after instruction higher than that before instruction using experimental set at the significant level of 0.05 and the class average normalized gain is in the medium gain

  10. Animal experimentation in Japan: regulatory processes and application for microbiological studies.

    PubMed

    Takahashi-Omoe, H; Omoe, K

    2007-07-01

    We have conducted animal experimentation as a highly effective technique in biological studies. Also in microbiological studies, we have used experimentation to prevent and treat many infectious diseases in humans and animals. In Japan, the 'Law for the Humane Treatment and Management of Animals', which covers the consideration of the three R principles, refinement, replacement and reduction for an international humane approach to animal experimentation came into effect in June 2006. Looking towards the straightforward operation of the law in animal experimentation, three government ministries established new basic guidelines for experimentation performed in their jurisdictional research and testing facilities. For future microbiological studies involving animals in Japan, we need to perform animal experiments according to the basic guidelines in association with overseas management systems. In this report, we discussed essential actions for the management of animal experimentation in microbiological studies in Japan.

  11. Skill Development in Experimental Courses

    ERIC Educational Resources Information Center

    Bagán, Héctor; Sayós, Rosa; García, José F.

    2015-01-01

    Experimental courses offer a good opportunity to work with competences, promoting the incorporation of strategies oriented towards motivating students to actively involve in the learning process, promoting reflexive learning and developing generic skills. This study presents different ways of developing and evaluating some important general…

  12. Facilitating Interactions through Structured Web-Based Bulletin Boards: A Quasi-Experimental Study on Promoting Learners' Critical Thinking Skills

    ERIC Educational Resources Information Center

    Yang, Ya-Ting C.; Newby, Timothy; Bill, Robert

    2008-01-01

    This experimental study investigated the effectiveness of structured Web-Based Bulletin Board (WBB) discussions in improving the critical thinking (CT) skills of learners involved in veterinary distance learning, as well as their attitudes toward learning via WBBs. The two dependent variables were learners' CT skills and their attitudes toward…

  13. Using Advance Organizers to Enhance Pupils' Achievement in Learning Poetry in English Language

    ERIC Educational Resources Information Center

    Muiruri, Mary; Wambugu, Patriciah; Wamukuru, Kuria

    2016-01-01

    The study was a quasi-experimental that investigated the effects of Advance Organizers (AO) on achievement in poetry. Target population was class seven pupils of Nakuru North Sub-county primary schools in Kenya. 160 pupils were involved in the study. Four sampled schools were randomly assigned to control and experimental groups in Solomon Four…

  14. Experimental studies illuminate the cultural transmission of percussive technologies in Homo and Pan

    PubMed Central

    Whiten, Andrew

    2015-01-01

    The complexity of Stone Age tool-making is assumed to have relied upon cultural transmission, but direct evidence is lacking. This paper reviews evidence bearing on this question provided through five related empirical perspectives. Controlled experimental studies offer special power in identifying and dissecting social learning into its diverse component forms, such as imitation and emulation. The first approach focuses on experimental studies that have discriminated social learning processes in nut-cracking by chimpanzees. Second come experiments that have identified and dissected the processes of cultural transmission involved in a variety of other force-based forms of chimpanzee tool use. A third perspective is provided by field studies that have revealed a range of forms of forceful, targeted tool use by chimpanzees, that set percussion in its broader cognitive context. Fourth are experimental studies of the development of flint knapping to make functional sharp flakes by bonobos, implicating and defining the social learning and innovation involved. Finally, new and substantial experiments compare what different social learning processes, from observational learning to teaching, afford good quality human flake and biface manufacture. Together these complementary approaches begin to delineate the social learning processes necessary to percussive technologies within the Pan–Homo clade. PMID:26483537

  15. Psychoeducational preparation of children for surgery: the importance of parental involvement.

    PubMed

    Li, Ho Cheung William; Lopez, Violeta; Lee, Tin Loi Isabel

    2007-01-01

    To examine the effects of therapeutic play intervention on outcomes of children undergoing day surgery, and to highlight the importance of parental involvement in the psychoeducational preparation of children for surgery. A randomized controlled trial, two group pre-test and repeated post-test, between subjects design was employed. Hong Kong Chinese children (7-12 years of age; n=203) admitted for elective surgery in a day surgery unit, along with their parents during a 13-month period, were invited to participate in the study. By using a simple complete randomization method, 97 of children with their parents were assigned to the experimental group receiving therapeutic play intervention, and 106 children with their parents were assigned to the control group receiving routine information preparation. The results showed that both children and their parents in the experimental group reported lower state anxiety scores in pre- and post-operative periods. Children in the experimental group exhibited fewer instances of negative emotional behaviors and parents in the experimental group reported greater satisfaction. The results, however, find no differences in children's post-operative pain between the two groups. The study provides empirical evidence to support the effectiveness of using therapeutic play intervention and the importance of parental involvement in the psychoeducational preparation of children for surgery. The findings heighten the awareness of the importance of integrating therapeutic play and parental involvement as essential components of holistic and quality nursing care to prepare children for surgery.

  16. An Experimental Introduction to Interlaboratory Exercises in Analytical Chemistry

    ERIC Educational Resources Information Center

    Puignou, L.; Llaurado, M.

    2005-01-01

    An experimental exercise on analytical proficiency studies in collaborative trials is proposed. This practical provides students in advanced undergraduate courses in chemistry, pharmacy, and biochemistry, with the opportunity to improve their quality assurance skills. It involves an environmental analysis, determining the concentration of a…

  17. Involvement of Cot/Tp12 in bone loss during periodontitis.

    PubMed

    Ohnishi, T; Okamoto, A; Kakimoto, K; Bandow, K; Chiba, N; Matsuguchi, T

    2010-02-01

    Periodontitis causes resorption of alveolar bone, in which RANKL induces osteoclastogenesis. The binding of lipopolysaccharide to Toll-like receptors causes phosphorylation of Cot/Tp12 to activate the MAPK cascade. Previous in vitro studies showed that Cot/Tp12 was essential for the induction of RANKL expression by lipopolysaccharide. In this study, we examined whether Cot/Tp12 deficiency reduced the progression of alveolar bone loss and osteoclastogenesis during experimental periodontitis. We found that the extent of alveolar bone loss and osteoclastogenesis induced by ligature-induced periodontitis was decreased in Cot/Tp12-deficient mice. In addition, reduction of RANKL expression was observed in periodontal tissues of Cot/Tp12-deficient mice with experimental periodontitis. Furthermore, we found that Cot/Tp12 was involved in the induction of TNF-alpha mRNA expression in gingiva of mice with experimental periodontitis. Our observations suggested that Cot/Tp12 is essential for the progression of alveolar bone loss and osteoclastogenesis in periodontal tissue during experimental periodontitis mediated through increased RANKL expression.

  18. A Computational Study of the Flow Physics of Acoustic Liners

    NASA Technical Reports Server (NTRS)

    Tam, Christopher

    2006-01-01

    The present investigation is a continuation of a previous joint project between the Florida State University and the NASA Langley Research Center Liner Physics Team. In the previous project, a study of acoustic liners, in two dimensions, inside a normal incidence impedance tube was carried out. The study consisted of two parts. The NASA team was responsible for the experimental part of the project. This involved performing measurements in an impedance tube with a large aspect ratio slit resonator. The FSU team was responsible for the computation part of the project. This involved performing direct numerical simulation (DNS) of the NASA experiment in two dimensions using CAA methodology. It was agreed that upon completion of numerical simulation, the computed values of the liner impedance were to be sent to NASA for validation with experimental results. On following this procedure good agreements were found between numerical results and experimental measurements over a wide range of frequencies and sound-pressure-level. Broadband incident sound waves were also simulated numerically and measured experimentally. Overall, good agreements were also found.

  19. [Dysregulation of the mTOR signaling pathway in the pathogenesis of autism spectrum disorders].

    PubMed

    Gabryel, Bożena; Kapałka, Agata; Sobczyk, Wojciech; Łabuzek, Krzysztof; Gawęda, Agnieszka; Janas-Kozik, Małgorzata

    2014-04-10

    Mammalian target of rapamycin (mTor) plays multiple role in central nervous system and is involved in regulation of cell viability, differentiation, transcription, translation, protein degradation, actin cytoskeletal organization and autophagy. Recent experimental and clinical studies reveal that disturbances of mTOR signaling are involved in the pathogenesis of autism spectrum disorders (ASD). This article reviews current data on the alteration in the mTOR transduction cascade, which may contribute to common neurobehavioral disorders typical for ASD. Moreover, the results of the latest experimental studies on the potential of mTOR inhibitors for the treatment of ASD are reviewed.

  20. Digital Storytelling for Enhancing Student Academic Achievement, Critical Thinking, and Learning Motivation: A Year-Long Experimental Study

    ERIC Educational Resources Information Center

    Yang, Ya-Ting C.; Wu, Wan-Chi I.

    2012-01-01

    The purpose of this study was to explore the impact of Digital storytelling (DST) on the academic achievement, critical thinking, and learning motivation of senior high school students learning English as a foreign language. The one-year study adopted a pretest and posttest quasi-experimental design involving 110 10th grade students in two English…

  1. EFFECTS OF VERBAL REINFORCEMENT ON INTELLECTIVE TASK PERFORMANCE AS A FUNCTION OF SELF-ESTEEM AND TASK-INVOLVEMENT. FINAL REPORT.

    ERIC Educational Resources Information Center

    FISCHER, EDWARD H.; HERSCHBERGER, AUSTIN C.

    USE OF THE VERBAL REINFORCEMENT TECHNIQUE (VRT) IN DEVELOPMENTAL, PERSONALITY, AND SOCIALIZATION STUDIES OFTEN RESTS ON TENUOUS AND UNTESTED ASSUMPTIONS. THIS STUDY EXAMINED FIVE VARIABLES WHICH HYPOTHETICALLY RELATE TO PERFORMANCE UNDER REINFORCEMENT--SELF-ESTEEM OF S. TASK-INVOLVEMENT, EXPERIMENTER, ORDINAL POSITION, AND FAMILY SIZE. THE METHOD…

  2. Conference on Chondrules and Their Origins

    NASA Technical Reports Server (NTRS)

    Hrametz, K.

    1983-01-01

    Chondrule parent materials, chondrule formation, and post-formational history are addressed. Contributions involving mineralogy petrology, geochemistry, geochronology, isotopic measurements, physical measurements, experimental studies, and theoretical studies are included.

  3. Exploring the Impact of Professional Development and Professional Practice on School Leaders' Self-Efficacy: A Quasi-Experimental Study

    ERIC Educational Resources Information Center

    Petridou, Alexandra; Nicolaidou, Maria; Karagiorgi, Yiasemina

    2017-01-01

    Self-efficacy is extensively discussed within social cognitive theory. This study aimed to explore the impact of professional development and practice on school leaders' self-efficacy in Cyprus. A quasi-experimental design involving 2 groups of novice secondary deputy head teachers was employed. All participants practised leadership at the time,…

  4. Effects of Reflective Inquiry Instructional Technique on Students' Academic Achievement and Ability Level in Electronic Work Trade in Technical Colleges

    ERIC Educational Resources Information Center

    Ogbuanya, T. C.; Owodunni, A. S.

    2015-01-01

    This study was designed to determine the effect of reflective inquiry instructional technique on achievement of students in Technical Colleges. The study adopted a pre-test, post-test, non-equivalent control group, quasi-experimental research design which involved groups of students in their intact class assigned to experimental group and control…

  5. Beneficial impact of exercise and obesity interventions on erectile function and its risk factors.

    PubMed

    Hannan, Johanna L; Maio, M Tina; Komolova, Marina; Adams, Michael A

    2009-03-01

    Erectile dysfunction (ED) is a multifaceted disease involving cardiovascular, metabolic, and hormonal factors and affects over 100 million men worldwide. ED has been shown to be a harbinger of underlying cardiovascular diseases (CVD), as there are common risk factors (aging, hypertension, obesity) and mechanistic basis. To provide an update on clinical and experimental evidence regarding the impact of lifestyle modifications, such as exercise and diet, with respect to changes in erectile function. Published evidence regarding the impact of aging, hypertension, and obesity on ED and CVD, as well as new experimental data linking obesity and diminished erectile responses. We reviewed the literature regarding common risk factors of ED and CVD, particularly involving obesity, as well as performed new analysis on the findings of other experimental studies involving diet and exercise interventions. Physical inactivity negatively impacts on erectile function, and experimental and clinical exercise interventions have been shown to improve sexual responses and overall cardiovascular health. Mediterranean-style diets and a reduction in caloric intake have been found to improve erectile function in men with the aspects of the metabolic syndrome. In addition, both clinical and experimental studies have confirmed that combining the two interventions provides additional benefit to erectile function, likely via reduced metabolic disturbances (e.g., inflammatory markers, insulin resistance), decreased visceral adipose tissue, and improvement in vascular function (e.g., increased endothelial function). Lifestyle modifications provide significant benefits to vascular health and erectile function in a population that is increasingly aged and more obese.

  6. The ethics of human volunteer studies involving experimental exposure to pesticides: unanswered dilemmas

    PubMed Central

    2010-01-01

    The controversy about the use of data from human volunteer studies involving experimental exposure to pesticides as part of regulatory risk assessment has been widely discussed, but the complex and interrelated scientific and ethical issues remain largely unresolved. This discussion paper, generated by authors who comprised a workgroup of the ICOH Scientific Committee on Rural Health, reviews the use of human experimental studies in regulatory risk assessment for pesticides with a view to advancing the debate as to when, if ever, such studies might be ethically justifiable. The discussion is based on three elements: (a) a review of discussion papers on the topic of human testing of pesticides and the positions adopted by regulatory agencies in developed countries; (b) an analysis of published and unpublished studies involving human testing with pesticides, both in the peer-reviewed literature and in the JMPR database; and (c) application of an ethical analysis to the problem. The paper identifies areas of agreement which include general principles that may provide a starting point on which to base criteria for judgements as to the ethical acceptability of such studies. However, the paper also highlights ongoing unresolved differences of opinion inherent in ethical analysis of contentious issues, which we propose should form a starting point for further debate and the development of guidelines to achieve better resolution of this matter. PMID:20718963

  7. Eliciting Reciprocal Peer-Tutoring Groups' Metacognitive Regulation through Structuring and Problematizing Scaffolds

    ERIC Educational Resources Information Center

    De Backer, Liesje; Van Keer, Hilde; Valcke, Martin

    2016-01-01

    The study examines whether structuring (SS) versus problematising scaffolds (PS) differently affect reciprocal peer-tutoring (RPT) groups' adoption of particular regulation skills, deep-level regulation, and tutee-initiated regulation. A quasi-experimental design involving two experimental groups (SS versus PS condition) was adopted. The first,…

  8. Is appendectomy a causative factor in ulcerative colitis?

    PubMed

    Russel, M G; Stockbrügger, R W

    1998-06-01

    There are strong indicators that the aetiology of inflammatory bowel disease should be regarded as multifactorial, involving an interaction between genetic and environmental factors which give rise to an inadequate immunological response. During the past decade at least seven case-control studies have shown an inverse association between appendectomy and ulcerative colitis. Conclusions have been that either ulcerative colitis protects against appendicitis, or appendectomy protects against ulcerative colitis. The immunological function of the appendix is not well known, but experimental studies suggest that the appendix is possibly an important site for priming of the cells involved in the development of inflammatory bowel disease. Experimental and prospective cohort studies are needed to provide more insight in a possible relation between ulcerative colitis and the appendix.

  9. Optimal Experiment Design for Thermal Characterization of Functionally Graded Materials

    NASA Technical Reports Server (NTRS)

    Cole, Kevin D.

    2003-01-01

    The purpose of the project was to investigate methods to accurately verify that designed , materials meet thermal specifications. The project involved heat transfer calculations and optimization studies, and no laboratory experiments were performed. One part of the research involved study of materials in which conduction heat transfer predominates. Results include techniques to choose among several experimental designs, and protocols for determining the optimum experimental conditions for determination of thermal properties. Metal foam materials were also studied in which both conduction and radiation heat transfer are present. Results of this work include procedures to optimize the design of experiments to accurately measure both conductive and radiative thermal properties. Detailed results in the form of three journal papers have been appended to this report.

  10. Online and offline peer led models against bullying and cyberbullying.

    PubMed

    Palladino, Benedetta Emanuela; Nocentini, Annalaura; Menesini, Ersilia

    2012-11-01

    The aim of the present study is to describe and evaluate an ongoing peer-led model against bullying and cyberbullying carried out with Italian adolescents. The evaluation of the project was made through an experimental design consisting of a pre-test and a post-test. Participants in the study were 375 adolescents (20.3% males), enrolled in 9th to 13th grades. The experimental group involved 231 students with 42 peer educators, and the control group involved 144 students. Results showed a significant decrease in the experimental group as compared to the control group for all the variables except for cyberbullying. Besides, in the experimental group we found a significant increase in adaptive coping strategies like problem solving and a significant decrease in maladaptive coping strategies like avoidance: these changes mediate the changes in the behavioural variables. In particular, the decrease in avoidance predicts the decrease in victimization and cybervictimization for peer educators and for the other students in the experimental classes whereas the increase in problem solving predicts the decrease in cyberbullying only in the peer educators group. Results are discussed following recent reviews on evidence based efficacy of peer led models.

  11. Fundamental phenomena on fuel decomposition and boundary layer combustion processes with applications to hybrid rocket motors

    NASA Technical Reports Server (NTRS)

    Kuo, Kenneth K.; Lu, Y. C.; Chiaverini, Martin J.; Harting, George C.

    1994-01-01

    An experimental study on the fundamental processes involved in fuel decomposition and boundary layer combustion in hybrid rocket motors is being conducted at the High Pressure Combustion Laboratory of the Pennsylvania State University. This research should provide an engineering technology base for development of large scale hybrid rocket motors as well as a fundamental understanding of the complex processes involved in hybrid propulsion. A high pressure slab motor has been designed for conducting experimental investigations. Oxidizer (LOX or GOX) is injected through the head-end over a solid fuel (HTPB) surface. Experiments using fuels supplied by NASA designated industrial companies will also be conducted. The study focuses on the following areas: measurement and observation of solid fuel burning with LOX or GOX, correlation of solid fuel regression rate with operating conditions, measurement of flame temperature and radical species concentrations, determination of the solid fuel subsurface temperature profile, and utilization of experimental data for validation of a companion theoretical study also being conducted at PSU.

  12. Writing Conversations: Fostering Metalinguistic Discussion about Writing

    ERIC Educational Resources Information Center

    Myhill, Debra; Jones, Susan; Wilson, Anthony

    2016-01-01

    This article draws on data from a national study, involving an experimental intervention with 54 schools across the country, in which teachers were mentored in a pedagogical approach involving explicit attention to grammatical choices and which advocated high-level metalinguistic discussion about textual choices. The research focused upon primary…

  13. The Influence of Computer-Assisted Instruction on Students' Conceptual Understanding of Chemical Bonding and Attitude toward Chemistry: A Case for Turkey

    ERIC Educational Resources Information Center

    Ozmen, Haluk

    2008-01-01

    In this study, the effect of computer-assisted instruction on conceptual understanding of chemical bonding and attitude toward chemistry was investigated. The study employed a quasi-experimental design involving 11 grade students; 25 in an experimental and 25 in a control group. The Chemical Bonding Achievement Test (CBAT) consisting of 15…

  14. Impulsivity in Multiplayer Online Battle Arena Gamers: Preliminary Results on Experimental and Self-Report Measures.

    PubMed

    Nuyens, Filip; Deleuze, Jory; Maurage, Pierre; Griffiths, Mark D; Kuss, Daria J; Billieux, Joël

    2016-06-01

    Background and aims Multiplayer Online Battle Arena (MOBA) games have become the most popular type of video games played worldwide, superseding the playing of Massively Multiplayer Online Role-Playing Games and First-Person Shooter games. However, empirical studies focusing on the use and abuse of MOBA games are still very limited, particularly regarding impulsivity, which is an indicator of addictive states but has not yet been explored in MOBA games. In this context, the objective of the present study is to explore the associations between impulsivity and symptoms of addictive use of MOBA games in a sample of highly involved League of Legends (LoL, currently the most popular MOBA game) gamers. Methods Thirty-six LoL gamers were recruited and completed both experimental (Single Key Impulsivity Paradigm) and self-reported impulsivity assessments (s-UPPS-P Impulsive Behavior Scale, Barratt Impulsiveness Scale), in addition to an assessment of problematic video game use (Problematic Online Gaming Questionnaire). Results Results showed links between impulsivity-related constructs and signs of excessive MOBA game involvement. Findings indicated that impaired ability to postpone rewards in an experimental laboratory task was strongly related to problematic patterns of MOBA game involvement. Although less consistent, several associations were also found between self-reported impulsivity traits and signs of excessive MOBA game involvement. Conclusions Despite these results are preliminary and based upon a small (self-selected) sample, the present study highlights potential psychological factors related to the addictive use of MOBA games.

  15. Impulsivity in Multiplayer Online Battle Arena Gamers: Preliminary Results on Experimental and Self-Report Measures

    PubMed Central

    Nuyens, Filip; Deleuze, Jory; Maurage, Pierre; Griffiths, Mark D.; Kuss, Daria J.; Billieux, Joël

    2016-01-01

    Background and aims Multiplayer Online Battle Arena (MOBA) games have become the most popular type of video games played worldwide, superseding the playing of Massively Multiplayer Online Role-Playing Games and First-Person Shooter games. However, empirical studies focusing on the use and abuse of MOBA games are still very limited, particularly regarding impulsivity, which is an indicator of addictive states but has not yet been explored in MOBA games. In this context, the objective of the present study is to explore the associations between impulsivity and symptoms of addictive use of MOBA games in a sample of highly involved League of Legends (LoL, currently the most popular MOBA game) gamers. Methods Thirty-six LoL gamers were recruited and completed both experimental (Single Key Impulsivity Paradigm) and self-reported impulsivity assessments (s-UPPS-P Impulsive Behavior Scale, Barratt Impulsiveness Scale), in addition to an assessment of problematic video game use (Problematic Online Gaming Questionnaire). Results Results showed links between impulsivity-related constructs and signs of excessive MOBA game involvement. Findings indicated that impaired ability to postpone rewards in an experimental laboratory task was strongly related to problematic patterns of MOBA game involvement. Although less consistent, several associations were also found between self-reported impulsivity traits and signs of excessive MOBA game involvement. Conclusions Despite these results are preliminary and based upon a small (self-selected) sample, the present study highlights potential psychological factors related to the addictive use of MOBA games. PMID:27156376

  16. Study of industry requirements that can be fulfilled by combustion experimentation aboard space station

    NASA Technical Reports Server (NTRS)

    Priem, Richard J.

    1988-01-01

    The purpose of this study is to define the requirements of commercially motivated microgravity combustion experiments and the optimal way for space station to accommodate these requirements. Representatives of commercial organizations, universities and government agencies were contacted. Interest in and needs for microgravity combustion studies are identified for commercial/industrial groups involved in fire safety with terrestrial applications, fire safety with space applications, propulsion and power, industrial burners, or pollution control. From these interests and needs experiments involving: (1) no flow with solid or liquid fuels; (2) homogeneous mixtures of fuel and air; (3) low flow with solid or liquid fuels; (4) low flow with gaseous fuel; (5) high pressure combustion; and (6) special burner systems are described and space station resource requirements for each type of experiment provided. Critical technologies involving the creation of a laboratory environment and methods for combining experimental needs into one experiment in order to obtain effective use of space station are discussed. Diagnostic techniques for monitoring combustion process parameters are identified.

  17. Computational protein design and protein-ligand interaction studies for the improvement of organophosphorus degrading potential of Deinococcus radiodurans.

    PubMed

    Manoharan, Prabu; Sridhar, J

    2018-05-01

    The organophosphorus hydrolase enzyme is involved in the catalyzing reaction that involve hydrolysis of organophosphate toxic compounds. An enzyme from Deinococcus radiodurans reported as homologous to phosphotriesterase and show activity against organophosphate. In the past activity of this enzyme is low and efforts made to improve the activity by experimental mutation study. However only very few organophosphates tested against very few catalytic site mutations. In order to improve the catalytic power of the organophosphorus hydrolase enzyme, we carried out systematic functional hotspot based protein engineering strategy. The mutants tested against 46 know organophosphate compounds using molecular docking study. Finally, we carried out an extensive molecular docking study to predict the binding of 46 organophosphate compounds to wild-type protein and mutant organophosphorus hydrolase enzyme. At the end we are able to improve the degrading potential of organophosphorus hydrolase enzyme against organophosphate toxic compounds. This preliminary study and the outcome would be useful guide for the experimental scientist involved in the bioremediation of toxic organophosphate compounds. Copyright © 2018 Elsevier Inc. All rights reserved.

  18. Requirements for Real-Time Laboratory Experimentation over the Internet.

    ERIC Educational Resources Information Center

    Salzmann, C.; Latchman, H. A.; Gillet, D.; Crisalle, O. D.

    A prototype system based on an inverted pendulum is used to study the Quality of Service and discuss requirements of remote-experimentation systems utilized for carrying out control engineering experiments over the Internet. This class of applications involves the transmission over the network of a variety of data types with their own peculiar…

  19. Psychological Interventions to Facilitate Employment Outcomes for Cancer Survivors: A Systematic Review and Meta-Analysis

    ERIC Educational Resources Information Center

    Fong, Carlton J.; Murphy, Kathleen M.; Westbrook, John D.; Markle, Minda M.

    2018-01-01

    Purpose: The objective was to examine experimental and quasi-experimental studies about interventions that (i) included behavioral, psychological, educational, or vocational components; (ii) involved cancer survivors aged 18 years or older; and (iii) assessed employment outcomes. Methods: The aims were both to describe the variety of interventions…

  20. Students' Reactions to Manual-Based Treatments for Substance Abuse: An Exploratory Study

    ERIC Educational Resources Information Center

    Simons, Lori; Jacobucci, Raymond; Houston, Hank

    2006-01-01

    A quasi-experimental research design with quantitative and qualitative methodologies was conducted to explore reactions of 21 students to treatment manuals for substance abuse. Students were randomized to experimental (n = 11) and attention-control (n = 10) groups involving exposure to one of two manual-based therapy interventions. Quantitative…

  1. BIOMIND Portal for Developing 21st Century Skills and Overcoming Students' Misconception in Biology Subject

    ERIC Educational Resources Information Center

    Vebrianto, Rian; Rery, Radjawaly Usman; Osman, Kamisah

    2016-01-01

    This research was conducted to investigate the effectiveness of BIOMIND portal in enhancing students' 21st century skills and overcoming their misconceptions in Biology subject. 118 Indonesian high school students were involved in this quasi-experimental study. The experimental group underwent learning experiences using BIOMIND portal whereas the…

  2. Overview of clinical research design.

    PubMed

    Hartung, Daniel M; Touchette, Daniel

    2009-02-15

    Basic concepts and terminology of clinical research design are presented for new clinical investigators. Clinical research, research involving human subjects, can be described as either observational or experimental. The findings of all clinical research can be threatened by issues of bias and confounding. Biases are systematic errors in how study subjects are selected or measured, which result in false inferences. Confounding is a distortion in findings that is attributable to mixing variable effects. Uncontrolled observation research is generally more prone to bias and confounding than experimental research. Observational research includes designs such as the cohort study, case-control study, and cross-sectional study, while experimental research typically involves a randomized controlled trial (RCT). The cohort study, which includes the RCT, defines subject allocation on the basis of exposure interest (e.g., drug, disease-management program) and follows the patients to assess the outcomes. The case-control study uses the primary outcome of interest (e.g., adverse event) to define subject allocation, and different exposures are assessed in a retrospective manner. Cross-sectional research evaluates both exposure and outcome concurrently. Each of these design methods possesses different strengths and weaknesses in answering research questions, as well as underlying many study subtypes. While experimental research is the strongest method for establishing causality, it can be difficult to accomplish under many scenarios. Observational clinical research offers many design alternatives that may be appropriate if planned and executed carefully.

  3. An experimental approach to free vibration analysis of smart composite beam

    NASA Astrophysics Data System (ADS)

    Yashavantha Kumar, G. A.; Sathish Kumar, K. M.

    2018-02-01

    Experimental vibration analysis is a main concern of this study. In designing any structural component the important parameter that has to be considered is vibration. The present work involves the experimental investigation of free vibration analysis of a smart beam. Smart beam consists of glass/epoxy composite as a main substrate and two PZT patches. The PZT patches are glued above and below the main beam. By experimentation the natural frequencies and mode shapes are obtained for both with and without PZT patches of a beam. Finally through experimentation the response of the smart beam is recorded.

  4. Parent Involvement Intervention in Developing Weight Management Skills for both Parents and Overweight/Obese Children.

    PubMed

    Kim, Hee Soon; Park, Jiyoung; Park, Kye-Yeong; Lee, Myung-Nam; Ham, Ok Kyung

    2016-03-01

    The purpose of the study was to evaluate a parent involvement intervention for childhood obesity intended to increase parents' skills in managing children's weight-related behavior and to improve child-parent relationships. Many studies reported on parental influence on childhood obesity, emphasizing parent involvement in prevention and management of childhood obesity. A randomized controlled trial was conducted. Forty-two parents of overweight/obese children were recruited from four cities and randomized to the experimental group or control group. The parental intervention was provided only to parents in the experimental group and consisted of weekly newsletters and text messages for a period of 5 weeks. Exercise classes and nutrition education were provided to all children. Lifestyle Behaviour Checklist and the Child-Parent Relationship Scale (CPRS) were used for measurement of parent outcome. For the child outcome, dietary self-efficacy, exercise frequency, and body mass index were measured. A mixed-design analysis of variance was performed with city location entered as a random effect. After the intervention, CPRS of parents and dietary self-efficacy of children showed an increase in the experimental group (p < .05). Intervention effects differed significantly according to the city location regarding the control efficacy of parents and dietary self-efficacy of children (p < .05). The results support the effectiveness of the parent involvement intervention in promoting child-parent relationship and dietary self-efficacy of children. However, a 5-week parent involvement intervention was not sufficient to produce significant changes in children's body mass index. Further research is needed to investigate effects of parent involvement intervention with long-term evaluation. Copyright © 2016. Published by Elsevier B.V.

  5. The effects of using diagramming as a representational technique on high school students' achievement in solving math word problems

    NASA Astrophysics Data System (ADS)

    Banerjee, Banmali

    Methods and procedures for successfully solving math word problems have been, and continue to be a mystery to many U.S. high school students. Previous studies suggest that the contextual and mathematical understanding of a word problem, along with the development of schemas and their related external representations, positively contribute to students' accomplishments when solving word problems. Some studies have examined the effects of diagramming on students' abilities to solve word problems that only involved basic arithmetic operations. Other studies have investigated how instructional models that used technology influenced students' problem solving achievements. Still other studies have used schema-based instruction involving students with learning disabilities. No study has evaluated regular high school students' achievements in solving standard math word problems using a diagramming technique without technological aid. This study evaluated students' achievement in solving math word problems using a diagramming technique. Using a quasi-experimental experimental pretest-posttest research design, quantitative data were collected from 172 grade 11 Hispanic English language learners (ELLS) and African American learners whose first language is English (EFLLs) in 18 classes at an inner city high school in Northern New Jersey. There were 88 control and 84 experimental students. The pretest and posttest of each participating student and samples of the experimental students' class assignments provided the qualitative data for the study. The data from this study exhibited that the diagramming method of solving math word problems significantly improved student achievement in the experimental group (p<.01) compared to the control group. The study demonstrated that urban, high school, ELLs benefited from instruction that placed emphasis on the mathematical vocabulary and symbols used in word problems and that both ELLs and EFLLs improved their problem solving success through careful attention to the creation and labeling of diagrams to represent the mathematics involved in standard word problems. Although Learnertype (ELL, EFLL), Classtype (Bilingual and Mixed), and Gender (Female, Male) were not significant indicators of student achievement, there was significant interaction between Treatment and Classtype at the level of the Bilingual students ( p<.01) and between Treatment and Learnertype at the level of the ELLs (p<.01).

  6. Evaluation of a Two-Phase Experimental Study of a Small Group ("MultiLit") Reading Intervention for Older Low-Progress Readers

    ERIC Educational Resources Information Center

    Buckingham, Jennifer; Beaman-Wheldall, Robyn; Wheldall, Kevin

    2014-01-01

    The study reported here examined the efficacy of a small group (Tier 2 in a three-tier Response to Intervention model) literacy intervention for older low-progress readers (in Years 3-6). This article focuses on the second phase of a two-phase, crossover randomized control trial involving 26 students. In Phase 1, the experimental group (E1)…

  7. Employee Involvement, Attitudes, and Productivity in High Technology Manufacturing: A Two-Year, Experimental Study.

    ERIC Educational Resources Information Center

    Stinnett, William D.; And Others

    To investigate methods of improving both employees' productivity and the quality of their work life, workers from four businesses were surveyed before and after their organizations implemented a total employees involvement program. Survey questions covered employees' perceptions of (1) the quality of the product produced, (2) the leadership's…

  8. 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.

  9. Parametric study of closed wet cooling tower thermal performance

    NASA Astrophysics Data System (ADS)

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

    2017-08-01

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

  10. Studies of nonlinear femtosecond pulse propagation in bulk materials

    NASA Astrophysics Data System (ADS)

    Eaton, Hilary Kaye

    2000-10-01

    Femtosecond pulse lasers are finding widespread application in a variety of fields including medical research, optical switching and communications, plasma formation, high harmonic generation, and wavepacket formation and control. As the number of applications for femtosecond pulses increases, so does the need to fully understand the linear and nonlinear processes involved in propagating these pulses through materials under various conditions. Recent advances in pulse measurement techniques, such as frequency-resolved optical gating (FROG), allow measurement of the full electric field of the pulse and have made detailed investigations of short- pulse propagation effects feasible. In this thesis, I present detailed experimental studies of my work involving nonlinear propagation of femtosecond pulses in bulk media. Studies of plane-wave propagation in fused silica extend the SHG form of FROG from a simple pulse diagnostic to a useful method of interrogating the nonlinear response of a material. Studies of nonlinear propagation are also performed in a regime where temporal pulse splitting occurs. Experimental results are compared with a three- dimensional nonlinear Schrödinger equation. This comparison fuels the development of a more complete model for pulse splitting. Experiments are also performed at peak input powers above those at which pulse splitting is observed. At these higher intensities, a broadband continuum is generated. This work presents a detailed study of continuum behavior and power loss as well as the first near-field spatial- spectral measurements of the generated continuum light. Nonlinear plane-wave propagation of short pulses in liquids is also investigated, and a non-instantaneous nonlinearity with a surprisingly short response time of 10 fs is observed in methanol. Experiments in water confirm that this effect in methanol is indeed real. Possible explanations for the observed effect are discussed and several are experimentally rejected. This thesis applies FROG as a powerful tool for science and not just a useful pulse diagnostic technique. Studies of three-dimensional propagation provide an in-depth understanding of the processes involved in femtosecond pulse splitting. In addition, the experimental investigations of continuum generation and pulse propagation in liquids provide new insights into the possible processes involved and should provide a useful comparison for developing theories.

  11. 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.

  12. Developing the Concept of Perimeter and Area in Students with Learning Disabilities (LD)

    ERIC Educational Resources Information Center

    Kozulin, Alex; Kazaz, Sigalit

    2017-01-01

    The present research is aimed at developing an educational program effective for the development of the concepts of perimeter and area in students with LD and testing this program. The study combined action research with quasi-experimental design involving experimental (LD) and comparison (non-LD) groups. The intervention program consisted of 12…

  13. Verb Form Indicates Discourse Segment Type in Biological Research Papers: Experimental Evidence

    ERIC Educational Resources Information Center

    de Waard, Anita; Maat, Henk Pander

    2012-01-01

    Corpus studies suggest that verb tense is a differentiating feature between, on the one hand, text pertaining to experimental results (involving methods and results) and on the other hand, text pertaining to more abstract concepts (i.e. regarding background knowledge in a field, hypotheses, problems or claims). In this paper, we describe a user…

  14. Experimental Study of Middle-Term Training in Social Cognition in Preschoolers

    ERIC Educational Resources Information Center

    Houssa, Marine; Nader-Grosbois, Nathalie

    2016-01-01

    In an experimental design, we examined the effects of middle-term training in social information processing (SIP) and in Theory of Mind (ToM) on preschoolers' social cognition and social adjustment. 48 preschoolers took part in a pre-test and post-test session involving cognitive, socio-cognitive and social adjustment (direct and indirect)…

  15. Practising Mental Rotation Using Interactive Desktop Mental Rotation Trainer (iDeMRT)

    ERIC Educational Resources Information Center

    Rafi, Ahmad; Samsudin, Khairulanuar

    2009-01-01

    An experimental study involving 30 undergraduates (mean age = 20.5 years) in mental rotation (MR) training was conducted in an interactive Desktop Mental Rotation Trainer (iDeMRT). Stratified random sampling assigned students into one experimental group and one control group. The former trained in iDeMRT and the latter trained in conventional…

  16. Using Different Types of Dictionaries for Improving EFL Reading Comprehension and Vocabulary Learning

    ERIC Educational Resources Information Center

    Alharbi, Majed A.

    2016-01-01

    This study investigated the effects of monolingual book dictionaries, popup dictionaries, and type-in dictionaries on improving reading comprehension and vocabulary learning in an EFL program. An experimental design involving four groups and a post-test was chosen for the experiment: (1) pop-up dictionary (experimental group 1); (2) type-in…

  17. 16 CFR § 1702.10 - Human experimental data involving the testing of human subjects.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 16 Commercial Practices 2 2013-01-01 2013-01-01 false Human experimental data involving the testing of human subjects. § 1702.10 Section § 1702.10 Commercial Practices CONSUMER PRODUCT SAFETY... PREVENTION PACKAGING ACT REQUIREMENTS; PETITION PROCEDURES AND REQUIREMENTS § 1702.10 Human experimental data...

  18. Experimental and Computational Study of Ductile Fracture in Small Punch Tests

    PubMed Central

    Bargmann, Swantje; Hähner, Peter

    2017-01-01

    A unified experimental-computational study on ductile fracture initiation and propagation during small punch testing is presented. Tests are carried out at room temperature with unnotched disks of different thicknesses where large-scale yielding prevails. In thinner specimens, the fracture occurs with severe necking under membrane tension, whereas for thicker ones a through thickness shearing mode prevails changing the crack orientation relative to the loading direction. Computational studies involve finite element simulations using a shear modified Gurson-Tvergaard-Needleman porous plasticity model with an integral-type nonlocal formulation. The predicted punch load-displacement curves and deformed profiles are in good agreement with the experimental results. PMID:29039748

  19. Experimental and Computational Study of Ductile Fracture in Small Punch Tests.

    PubMed

    Gülçimen Çakan, Betül; Soyarslan, Celal; Bargmann, Swantje; Hähner, Peter

    2017-10-17

    A unified experimental-computational study on ductile fracture initiation and propagation during small punch testing is presented. Tests are carried out at room temperature with unnotched disks of different thicknesses where large-scale yielding prevails. In thinner specimens, the fracture occurs with severe necking under membrane tension, whereas for thicker ones a through thickness shearing mode prevails changing the crack orientation relative to the loading direction. Computational studies involve finite element simulations using a shear modified Gurson-Tvergaard-Needleman porous plasticity model with an integral-type nonlocal formulation. The predicted punch load-displacement curves and deformed profiles are in good agreement with the experimental results.

  20. Study concerning the loads over driver's chests in car crashes with cars of the same or different generation

    NASA Astrophysics Data System (ADS)

    Ispas, N.; Năstăsoiu, M.

    2016-08-01

    Reducing occupant injuries for cars involves in traffic accidents is a main target of today cars designers. Known as active or passive safety, many technological solutions were developing over the time for an actual better car's occupant safety. In the real world, in traffic accidents are often involved cars from different generations with various safety historical solutions. The main aim of these papers are to quantify the influences over the car driver chest loads in cases of same or different generation of cars involved in side car crashes. Both same and different cars generations were used for the study. Other goal of the paper was the study of in time loads conformity for diver's chests from both cars involved in crash. The paper's experimental results were obtained by support of DSD, Dr. Steffan Datentechnik GmbH - Linz, Austria. The described tests were performed in full test facility of DSD Linz, in “Easter 2015 PC-Crash Seminar”. In all crashes we obtaining results from both dummy placed in impacted and hits car. The novelty of the paper are the comparisons of data set from each of driver (dummy) of two cars involved in each of six experimental crashes. Another novelty of this paper consists in possibilities to analyse the influences of structural historical cars solutions over deformation and loads in cases of traffic accidents involved. Paper's conclusions can be future used for car passive safety improvement.

  1. Neuropharmacological effects of essential oil from the leaves of Croton conduplicatus Kunth and possible mechanisms of action involved.

    PubMed

    Oliveira Júnior, Raimundo Gonçalves de; Ferraz, Christiane Adrielly Alves; Silva, Juliane Cabral; de Andrade Teles, Roxana Braga; Silva, Mariana Gama; Diniz, Tâmara Coimbra; Dos Santos, Uiliane Soares; de Souza, Ana Valéria Vieira; Nunes, Carlos Eduardo Pereira; Salvador, Marcos José; Lorenzo, Vitor Prates; Quintans Júnior, Lucindo José; Almeida, Jackson Roberto Guedes da Silva

    2018-07-15

    Croton conduplicatus Kunth (Euphorbiaceae) is a Brazilian aromatic medicinal plant, widely known as "quebra-faca". In folk medicine, its leaves and stem-barks are used as a natural analgesic for the treatment of headaches. In this study, we describe for the first time the neuropharmacological potential of the essential oil obtained from the leaves of Croton conduplicatus (EO) in experimental models of pain, anxiety and insomnia. The mechanisms of action involved in these activities were also investigated. Different experimental models were used to evaluate the antinociceptive (acetic acid, formalin-induced nociception and hot plate tests), anxiolytic (elevated plus maze and hole board tests) and sedative (thiopental-induced sleeping time) effects of EO in mice. EO was evaluated in three different doses (25, 50 and 100 mg/kg, i.p.) and compared with positive and negative controls in all experimental protocols. When appropriate, animals were pretreated with pharmacological antagonists (naloxone, atropine and flumazenil) in order to evaluate the mechanisms of action involved. A docking study also was performed to identify possible targets involved. EO (25, 50 and 100 mg/kg, i.p.) demonstrated a significant antinociceptive activity in all experimental models. Pretreatment with naloxone or atropine reversed the antinociceptive response (p < 0.05), suggesting the involvement of opioid and muscarinic receptors, respectively. A docking study was performed with the major components identified in EO (1,8 cineole - 21.42%, spathulenol - 15.47%, p-cymene - 12.41% and caryophyllene oxide - 12.15%), demonstrating favorable interaction profile with different subtypes of muscarinic (M2, M3 and M4) and opioids (delta and mu) receptors. EO also showed anxiolytic (mainly at doses of 25 and 50 mg/kg, i.p.) and sedative (only at the dose of 100 mg/kg, i.p.) effects in mice. These pharmacological responses were reversed by flumazenil (p < 0.05), indicating possible involvement of GABA A receptors. Our findings support the traditional use of this plant as a natural analgesic and suggest that EO is a multi-target natural product, presenting not only antinociceptive effect but also anxiolytic and sedative activities depending on the dose used. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. HOLONET: a network for training holography

    NASA Astrophysics Data System (ADS)

    Pombo, Pedro; Santos, Emanuel

    2014-07-01

    Holography is an optics technique based on wave physics and lasers with several applications at our day life. The production of holograms involves experimental work based on hands-on activities and creativity. All these elements can contribute to the promotion of experimental teaching of optics and training on holography. The hologram itself acting as a final result from a long process of research and study can enable the engagement of high school students on physics and promote the stimulus on optics learning. Taking these assumptions into account a network of schools working on holography was built involving thirty schools from all country. Holography systems were developed and several hands-on activities were constructed. During last sixteen years students are working on laser optics and holography producing different kinds of holograms. This study presents all holography labs implemented at schools and it will analyzed the holography systems and materials developed for students. Training strategy will be discussed and holograms obtained by students will be presented. Results obtained show us that holography can be implemented as a strategy for promoting the learning of optics and it is a particular way to involve students on experimental work and lab research. Results obtained during this study will be presented in detail and analyzed with focus on students performance. Educational results, teachers training, prizes and other positive outcomes will be discussed and compared.

  3. 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

  4. Experimental Determination of Spinel/Melt, Olivine/Melt, and Pyroxene/Melt Partition Coefficients for Re, Ru, Pd, Au, and Pt

    NASA Technical Reports Server (NTRS)

    Righter, K.; Campbell, A. J.; Humayun, M.

    2003-01-01

    Experimental studies have identified spinels as important hosts phases for many of the highly siderophile elements (HSE). Yet experimental studies involving chromite or Cr-rich spinel have been lacking. Experimental studies of partitioning of HSEs between silicate, oxides and silicate melt are plagued by low solubilities and the presence of small metallic nuggets at oxygen fugacities relevant to magmas, which interfere with analysis of the phases of interest. We have circumvented these problems in two ways: 1) performing experiments at oxidized conditions, which are still relevant to natural systems but in which nuggets are not observed, and 2) analysis of run products with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS), allowing a combination of high sensitivity and good spatial resolution.

  5. Effects of Training Method and Gender on Learning 2D/3D Geometry

    ERIC Educational Resources Information Center

    Khairulanuar, Samsudin; Nazre, Abd Rashid; Jamilah, H.; Sairabanu, Omar Khan; Norasikin, Fabil

    2010-01-01

    This article reports the findings of an experimental study involving 36 primary school students (16 girls, 20 boys, Mean age = 9.5 years, age range: 8-10 years) in geometrical understanding of 2D and 3D objects. Students were assigned into two experimental groups and one control group based on a stratified random sampling procedure. The first…

  6. Examining the relationship between psychosocial and behavioral proxies for future consumption behavior: self-reported impact and bidding behavior in an experimental auction study on cigarette labeling

    PubMed Central

    Rousu, Matthew C.; Thrasher, James F.

    2014-01-01

    Experimental and observational research often involves asking consumers to self-report the impact of some proposed option. Because self-reported responses involve no consequence to the respondent for falsely revealing how he or she feels about an issue, self-reports may be subject to social desirability and other influences that bias responses in important ways. In this article, we analyzed data from an experiment on the impact of cigarette packaging and pack warnings, comparing smokers’ self-reported impact (four-item scale) and the bids they placed in experimental auctions to estimate differences in demand. The results were consistent across methods; however, the estimated effect size associated with different warning labels was two times greater for the four-item self-reported response scale when compared to the change in demand as indicated by auction bids. Our study provides evidence that self-reported psychosocial responses provide a valid proxy for behavioral change as reflected by experimental auction bidding behavior. More research is needed to better understand the advantages and disadvantages of behavioral economic methods and traditional self-report approaches to evaluating health behavior change interventions. PMID:24399267

  7. Involvement of the CD200 receptor complex in microglia activation in experimental glaucoma

    PubMed Central

    Taylor, Sarah; Calder, Claudia J.; Albon, Julie; Erichsen, Jonathan T.; Boulton, Micheal E.; Morgan, James E.

    2013-01-01

    The interaction of the myeloid restricted molecule CD200R with its widely expressed ligand CD200 is involved in the down-regulation of microglia activation. In the present study, we examined the involvement of CD200R in microglia activation in experimental ocular hypertension to determine the role of microglia activation in retinal ganglion cell (RGC) death, the key pathological event in glaucoma. Experimental glaucoma was induced in adult Brown Norway rats by sclerosis of the episcleral veins with the injection of hypertonic saline. Immunohistochemical methods were used to determine the involvement of microglia using GFAP, CD45, OX42 and OX41 and the involvement of CD200 and CD200R in the optic nerve head. Our data demonstrate the increased presence of microglia within the optic nerve head during ocular hypertension, identified by positive staining with OX42 and OX41. The peak of microglia correlates with peak in RGC death at days 20–27 (T3) post OHT induction. In addition, CD200 and CD200R positive cells were increased in ocular hypertensive eyes. Increased expression of CD200 was detected in the early phase (days 1–7; T1) of OHT and decreased over time, whilst the expression of CD200R was detected in the middle phase (days 20–27; T3) of OHT, correlating with the increase in microglia markers. Changes in the expression of CD200R/CD200 occur early in experimental glaucoma and precede the peak in microglia infiltration and RGC death, suggesting that CD200R-positive microglia play an important role in the initiation of RGC death during OHT, indicating a potential area for therapeutic intervention in treating glaucoma. PMID:21296076

  8. Stable Rat Model of Mechanical Allodynia in Diabetic Peripheral Neuropathy: The Role of Nerve Compression.

    PubMed

    Liao, Chenlong; Yang, Min; Liu, Pengfei; Zhong, Wenxiang; Zhang, Wenchuan

    2018-05-01

     Preclinical studies involving animal models are essential for understanding the underlying mechanisms of diabetic neuropathic pain.  Rats were divided into four groups: two controls and two experimental. Diabetes mellitus was induced by streptozotocin (STZ) injection in two experimental groups. The first group involved one sham operation. The second group involved one latex tube encircling the sciatic nerve. The vehicle-injection rats were used as two corresponding control groups: sham operation and encircled nerves. By the third week, STZ-injected rats with encircled nerves were further divided into three subgroups: one involving continuing observation and the other two involving decompression (removal of the latex tube) at different time points (third week and fifth week). Weight and blood glucose were monitored, and behavioral analysis, including paw withdrawal threshold (PWT) and latency, was performed every week during the experimental period (7 weeks).  Hyperglycemia was induced in all STZ-injected rats. A significant increase in weight was observed in the control groups when compared with the experimental groups. By the third week, more STZ-injected rats with encircled nerves developed mechanical allodynia than those without ( P  < 0.05), while no significant difference was noted ( P  > 0.05) on the incidence of thermal hyperalgesia. Mechanical allodynia, but not thermal hyperalgesia, could be ameliorated by the removal of the latex tube at an early stage (third week).  With the combined use of a latex tube and STZ injection, a stable rat model of painful diabetic peripheral neuropathy (DPN) manifesting both thermal hyperalgesia and mechanical allodynia has been established. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  9. Intramolecular allyl transfer reaction from allyl ether to aldehyde groups: experimental and theoretical studies.

    PubMed

    Franco, Delphine; Wenger, Karine; Antonczak, Serge; Cabrol-Bass, Daniel; Duñach, Elisabet; Rocamora, Mercè; Gomez, Montserrat; Muller, Guillermo

    2002-02-02

    The intramolecular transfer of the allyl group of functionalized allyl aryl ethers to an aldehyde group in the presence of Ni0 complexes was studied from chemical, electrochemical and theoretical points of view. The chemical reaction involves the addition of Ni0 to the allyl ether followed by stoichiometric allylation. The electrochemical process is catalytic in nickel and involves the reduction of intermediate eta3-allylnickel(II) complexes.

  10. An experimental study on particle effects in liquid sheets

    NASA Astrophysics Data System (ADS)

    Sauret, Alban; Troger, Anthony; Jop, Pierre

    2017-06-01

    Many industrial processes, such as surface coating or liquid transport in tubes, involve liquid sheets or thin films of suspensions. In these situations, the thickness of the liquid film becomes comparable to the particle size, which leads to unexpected dynamics. In addition, the classical constitutive rheological law for suspensions cannot be applied as the continuum approximation is no longer valid. Here, we consider experimentally a transient particle-laden liquid sheet that expands radially. We characterize the influence of the particles on the shape of the liquid film and the atomization process. We highlight that the presence of particles modifies the thickness and stability of the liquid sheet. Our study suggests that the influence of particles through capillary effects can modify significantly the dynamics of processes that involve suspensions and particles confined in liquid films.

  11. Understanding the role consumer involvement plays in the effectiveness of hospital advertising.

    PubMed

    McCullough, Tammy; Dodge, H Robert

    2002-01-01

    Both intensified competition and greater consumer participation in the choice process for healthcare has increased the importance of advertising for health care providers and seriously challenged many of the preconceptions regarding advertising. This study investigates the effectiveness of advertising under conditions of high and low involvement using the Elaboration Likelihood Model to develop hypotheses that are tested in a 2 x 2 x 2 experimental design. The study findings provide insights into the influence of message content and message source on consumers categorized as high or low involvement. It was found that consumers classified as high-involvement are more influenced by a core service-relevant message than those consumers classified as low-involvement. Moreover, a non-physician spokesperson was found to have as much or more influence as a physician spokesperson regardless of the consumers' involvement level.

  12. A SIMPLE METHOD FOR EVALUATING DATA FROM AN INTERLABORATORY STUDY

    EPA Science Inventory

    Large-scale laboratory-and method-performance studies involving more than about 30 laboratories may be evaluated by calculating the HORRAT ratio for each test sample (HORRAT=[experimentally found among-laboratories relative standard deviation] divided by [relative standard deviat...

  13. IR-IR Conformation Specific Spectroscopy of Na+(Glucose) Adducts

    NASA Astrophysics Data System (ADS)

    Voss, Jonathan M.; Kregel, Steven J.; Fischer, Kaitlyn C.; Garand, Etienne

    2018-01-01

    We report an IR-IR double resonance study of the structural landscape present in the Na+(glucose) complex. Our experimental approach involves minimal modifications to a typical IR predissociation setup, and can be carried out via ion-dip or isomer-burning methods, providing additional flexibility to suit different experimental needs. In the current study, the single-laser IR predissociation spectrum of Na+(glucose), which clearly indicates contributions from multiple structures, was experimentally disentangled to reveal the presence of three α-conformers and five β-conformers. Comparisons with calculations show that these eight conformations correspond to the lowest energy gas-phase structures with distinctive Na+ coordination. [Figure not available: see fulltext.

  14. A School-Based Motivational Intervention to Promote Physical Activity from a Self-Determination Theory Perspective

    ERIC Educational Resources Information Center

    González-Cutre, David; Sierra, Ana C.; Beltrán-Carrillo, Vicente J.; Peláez-Pérez, Manuel; Cervelló, Eduardo

    2018-01-01

    The authors analyzed the effects of a multidimensional intervention to promote physical activity (PA) in school, based on self-determination theory. The study involved 88 students, between 14 and 17 years old, who were divided into a control group (n = 59) and an experimental group (n = 29). In the experimental group, a 6-month intervention was…

  15. A Short Dance-Exercise Intervention as a Strategy for Improving Quality of Life in Inactive Workers

    ERIC Educational Resources Information Center

    Barranco-Ruiz, Yaira; Mandic, Sandra; Paz-Viteri, Susana; Guerendiain, Marcela; Sandoval, FaustoVinicio; Villa-González, Emilio

    2017-01-01

    Objective: To investigate the effects of a short exercise intervention based on the use of a Zumba Fitness® programme on the quality of life (QoL) in inactive adult workers. Design: Non-experimental pre-test/post-test study involving one experimental group of inactive university workers. Setting: Riobamba in the Andean region of central Ecuador.…

  16. A Study of the Generalizability of Teacher Change Quasi-Experiments

    ERIC Educational Resources Information Center

    Stringfield, Samuel; Schaffer, Eugene; Devlin-Scherer, Roberta

    2017-01-01

    Quasi-experimental teacher effectiveness studies have indicated that properly designed staff development programs can lead to changes in teacher and student behavior and to gains in student achievement. Those studies involved workshop series led by nationally known scholars. Using instructors from varied backgrounds, the current study examined the…

  17. Experiments With Magnetic Vector Potential

    ERIC Educational Resources Information Center

    Skinner, J. W.

    1975-01-01

    Describes the experimental apparatus and method for the study of magnetic vector potential (MVP). Includes a discussion of inherent errors in the calculations involved, precision of the results, and further applications of MVP. (GS)

  18. Andrew Norman | NREL

    Science.gov Websites

    MOCVD grown InP-based materials and a LINK project involving TEM studies of non-planar and localized . M. Jones, Appl. Phys. Lett. 93 (2008) 123505. "Theoretical and experimental examination of the

  19. Experimental studies of ionospheric irregularities and related plasma processes

    NASA Technical Reports Server (NTRS)

    Baker, Kay D.

    1992-01-01

    Utah State University (USU) continued its program of measuring and interpreting electron density and its variations in a variety of ionospheric conditions with the Experimental Studies of Ionospheric Irregularities and Related Plasma Processes program. The program represented a nearly ten year effort to provide key measurements of electron density and its fluctuations using sounding rockets. The program also involved the joint interpretation of the results in terms of ionospheric processes. A complete campaign summary and a brief description of the major rocket campaigns are also included.

  20. Mitochondrial Dysfunction in Parkinson's Disease: Pathogenesis and Neuroprotection

    PubMed Central

    Mounsey, Ross B.; Teismann, Peter

    2011-01-01

    Mitochondria are vitally important organelles involved in an array of functions. The most notable is their prominent role in energy metabolism, where they generate over 90% of our cellular energy in the form of ATP through oxidative phosphorylation. Mitochondria are involved in various other processes including the regulation of calcium homeostasis and stress response. Mitochondrial complex I impairment and subsequent oxidative stress have been identified as modulators of cell death in experimental models of Parkinson's disease (PD). Identification of specific genes which are involved in the rare familial forms of PD has further augmented the understanding and elevated the role mitochondrial dysfunction is thought to have in disease pathogenesis. This paper provides a review of the role mitochondria may play in idiopathic PD through the study of experimental models and how genetic mutations influence mitochondrial activity. Recent attempts at providing neuroprotection by targeting mitochondria are described and their progress assessed. PMID:21234411

  1. Comprehensive Genetic Characterization of Intraprostatic Chronic Inflammation and Prostate Cancer in African American Men

    DTIC Science & Technology

    2017-09-01

    with new methodologies of intratumoral phylogenetic analyses, will yield pivotal information in elucidating the key genes involved evolution of PCa...combined with both clinical and experimental genetic data produced by this study may empower patients and doctors to make personalized treatment decisions...sequencing, paired with new methodologies of intratumoral phylogenetic analyses, will yield pivotal information in elucidating the key genes involved

  2. The Effects of Group Relaxation Training/Large Muscle Exercise, and Parental Involvement on Attention to Task, Impulsivity, and Locus of Control among Hyperactive Boys.

    ERIC Educational Resources Information Center

    Porter, Sally S.; Omizo, Michael M.

    1984-01-01

    The study examined the effects of group relaxation training/large muscle exercise and parental involvement on attention to task, impulsivity, and locus of control among 34 hyperactive boys. Following treatment both experimental groups recorded significantly higher attention to task, lower impulsivity, and lower locus of control scores. (Author/CL)

  3. Une Experience d'enseignement programme de la grammaire francaise (An Experiment in Programed Instruction of French Grammar).

    ERIC Educational Resources Information Center

    Girard, Jacques D.

    An experiment is reported involving the teaching of the agreement of the past participle without an auxiliary verb, with "avoir" and with "etre," patterned after the studies of S. Roller in 1952-53 in this area. The initial experimentation is updated and involves the use of a Skinnerian model of programed instruction. The objectives, operational…

  4. Impact of an inquiry unit on grade 4 students' science learning

    NASA Astrophysics Data System (ADS)

    Di Mauro, María Florencia; Furman, Melina

    2016-09-01

    This paper concerns the identification of teaching strategies that enhance the development of 4th grade students' experimental design skills at a public primary school in Argentina. Students' performance in the design of relevant experiments was evaluated before and after an eight-week intervention compared to a control group, as well as the persistence of this learning after eight months. The study involved a quasi-experimental longitudinal study with pre-test/post-test/delayed post-test measures, complemented with semi-structured interviews with randomly selected students. Our findings showed improvement in the experimental design skills as well as its sustainability among students working with the inquiry-based sequence. After the intervention, students were able to establish valid comparisons, propose pertinent designs and identify variables that should remain constant. Contrarily, students in the control group showed no improvement and continued to solve the posed problems based on prior beliefs. In summary, this paper shows evidence that implementing inquiry-based units involving problems set in cross-domain everyday situations that combine independent student work with teacher guidance significantly improves the development of scientific skills in real classroom contexts.

  5. Investigating the Energetic Ordering of Stable and Metastable TiO 2 Polymorphs Using DFT+ U and Hybrid Functionals

    DOE PAGES

    Curnan, Matthew T.; Kitchin, John R.

    2015-08-12

    Prediction of transition metal oxide BO 2 (B = Ti, V, etc.) polymorph energetic properties is critical to tunable material design and identifying thermodynamically accessible structures. Determining procedures capable of synthesizing particular polymorphs minimally requires prior knowledge of their relative energetic favorability. Information concerning TiO 2 polymorph relative energetic favorability has been ascertained from experimental research. In this study, the consistency of first-principles predictions and experimental results involving the relative energetic ordering of stable (rutile), metastable (anatase and brookite), and unstable (columbite) TiO 2 polymorphs is assessed via density functional theory (DFT). Considering the issues involving electron–electron interaction and chargemore » delocalization in TiO 2 calculations, relative energetic ordering predictions are evaluated over trends varying Ti Hubbard U 3d or exact exchange fraction parameter values. Energetic trends formed from varying U 3d predict experimentally consistent energetic ordering over U 3d intervals when using GGA-based functionals, regardless of pseudopotential selection. Given pertinent linear response calculated Hubbard U values, these results enable TiO 2 polymorph energetic ordering prediction. Here, the hybrid functional calculations involving rutile–anatase relative energetics, though demonstrating experimentally consistent energetic ordering over exact exchange fraction ranges, are not accompanied by predicted fractions, for a first-principles methodology capable of calculating exact exchange fractions precisely predicting TiO 2 polymorph energetic ordering is not available.« less

  6. The Study of a Simple Redox Reaction as an Experimental Approach to Chemical Kinetics.

    ERIC Educational Resources Information Center

    Elias, Horst; Zipp, Arden P.

    1988-01-01

    Recommends using iodide ions and peroxodisulfate ions for studying rate laws instead of the standard iodine clock for kinetic study. Presents the methodology and a discussion of the kinetics involved for a laboratory experiment for a high school or introductory college course. (ML)

  7. A model of fluid and solute exchange in the human: validation and implications.

    PubMed

    Bert, J L; Gyenge, C C; Bowen, B D; Reed, R K; Lund, T

    2000-11-01

    In order to understand better the complex, dynamic behaviour of the redistribution and exchange of fluid and solutes administered to normal individuals or to those with acute hypovolemia, mathematical models are used in addition to direct experimental investigation. Initial validation of a model developed by our group involved data from animal experiments (Gyenge, C.C., Bowen, B.D., Reed, R.K. & Bert, J.L. 1999b. Am J Physiol 277 (Heart Circ Physiol 46), H1228-H1240). For a first validation involving humans, we compare the results of simulations with a wide range of different types of data from two experimental studies. These studies involved administration of normal saline or hypertonic saline with Dextran to both normal and 10% haemorrhaged subjects. We compared simulations with data including the dynamic changes in plasma and interstitial fluid volumes VPL and VIT respectively, plasma and interstitial colloid osmotic pressures PiPL and PiIT respectively, haematocrit (Hct), plasma solute concentrations and transcapillary flow rates. The model predictions were overall in very good agreement with the wide range of experimental results considered. Based on the conditions investigated, the model was also validated for humans. We used the model both to investigate mechanisms associated with the redistribution and transport of fluid and solutes administered following a mild haemorrhage and to speculate on the relationship between the timing and amount of fluid infusions and subsequent blood volume expansion.

  8. Cadmium Handling, Toxicity and Molecular Targets Involved during Pregnancy: Lessons from Experimental Models.

    PubMed

    Jacobo-Estrada, Tania; Santoyo-Sánchez, Mitzi; Thévenod, Frank; Barbier, Olivier

    2017-07-22

    Even decades after the discovery of Cadmium (Cd) toxicity, research on this heavy metal is still a hot topic in scientific literature: as we wrote this review, more than 1440 scientific articles had been published and listed by the PubMed.gov website during 2017. Cadmium is one of the most common and harmful heavy metals present in our environment. Since pregnancy is a very particular physiological condition that could impact and modify essential pathways involved in the handling of Cd, the prenatal life is a critical stage for exposure to this non-essential element. To give the reader an overview of the possible mechanisms involved in the multiple organ toxic effects in fetuses after the exposure to Cd during pregnancy, we decided to compile some of the most relevant experimental studies performed in experimental models and to summarize the advances in this field such as the Cd distribution and the factors that could alter it (diet, binding-proteins and membrane transporters), the Cd-induced toxicity in dams (preeclampsia, fertility, kidney injury, alteration in essential element homeostasis and bone mineralization), in placenta and in fetus (teratogenicity, central nervous system, liver and kidney).

  9. Cadmium Handling, Toxicity and Molecular Targets Involved during Pregnancy: Lessons from Experimental Models

    PubMed Central

    Santoyo-Sánchez, Mitzi; Thévenod, Frank; Barbier, Olivier

    2017-01-01

    Even decades after the discovery of Cadmium (Cd) toxicity, research on this heavy metal is still a hot topic in scientific literature: as we wrote this review, more than 1440 scientific articles had been published and listed by the PubMed.gov website during 2017. Cadmium is one of the most common and harmful heavy metals present in our environment. Since pregnancy is a very particular physiological condition that could impact and modify essential pathways involved in the handling of Cd, the prenatal life is a critical stage for exposure to this non-essential element. To give the reader an overview of the possible mechanisms involved in the multiple organ toxic effects in fetuses after the exposure to Cd during pregnancy, we decided to compile some of the most relevant experimental studies performed in experimental models and to summarize the advances in this field such as the Cd distribution and the factors that could alter it (diet, binding-proteins and membrane transporters), the Cd-induced toxicity in dams (preeclampsia, fertility, kidney injury, alteration in essential element homeostasis and bone mineralization), in placenta and in fetus (teratogenicity, central nervous system, liver and kidney). PMID:28737682

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

    NASA Technical Reports Server (NTRS)

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

    2014-01-01

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

  11. Newspapers in Science Education: A Study Involving Sixth Grade Students

    ERIC Educational Resources Information Center

    Lai, Ching-San; Wang, Yun-Fei

    2016-01-01

    The purpose of this study was to explore the learning performance of sixth grade elementary school students using newspapers in science teaching. A quasi-experimental design with a single group was used in this study. Thirty-three sixth grade elementary school students participated in this study. The research instruments consisted of three…

  12. Malnutrition: A Deterrent to Human Progress

    ERIC Educational Resources Information Center

    Johnson, Nancy E.; Found, R. Elaine

    1971-01-01

    Authors discuss the effects of malnutrition on retardation of mental development and intellectual capacity. Research findings on undernourished experimental animals are cited as well as studies involving children suffering the effects of malnutrition in infancy. (Editor/LF)

  13. Estimation of medium effects on equilibrium constants in moderate and high ionic strength solutions at elevated temperatures by using specific interaction theory (SIT): Interaction coefficients involving Cl, OH- and Ac- up to 200°C and 400 bars

    PubMed Central

    Xiong, Yongliang

    2006-01-01

    In this study, a series of interaction coefficients of the Brønsted-Guggenheim-Scatchard specific interaction theory (SIT) have been estimated up to 200°C and 400 bars. The interaction coefficients involving Cl- estimated include ε(H+, Cl-), ε(Na+, Cl-), ε(Ag+, Cl-), ε(Na+, AgCl2 -), ε(Mg2+, Cl-), ε(Ca2+, Cl-), ε(Sr2+, Cl-), ε(Ba2+, Cl-), ε(Sm3+, Cl-), ε(Eu3+, Cl-), ε(Gd3+, Cl-), and ε(GdAc2+, Cl-). The interaction coefficients involving OH- estimated include ε(Li+, OH-), ε(K+, OH-), ε(Na+, OH-), ε(Cs+, OH-), ε(Sr2+, OH-), and ε(Ba2+, OH-). In addition, the interaction coefficients of ε(Na+, Ac-) and ε(Ca2+, Ac-) have also been estimated. The bulk of interaction coefficients presented in this study has been evaluated from the mean activity coefficients. A few of them have been estimated from the potentiometric and solubility studies. The above interaction coefficients are tested against both experimental mean activity coefficients and equilibrium quotients. Predicted mean activity coefficients are in satisfactory agreement with experimental data. Predicted equilibrium quotients are in very good agreement with experimental values. Based upon its relatively rapid attainment of equilibrium and the ease of determining magnesium concentrations, this study also proposes that the solubility of brucite can be used as a pH (pcH) buffer/sensor for experimental systems in NaCl solutions up to 200°C by employing the predicted solubility quotients of brucite in conjunction with the dissociation quotients of water and the first hydrolysis quotients of Mg2+, all in NaCl solutions. PMID:16759370

  14. Highlighting the Need for Systems-Level Experimental Characterization of Plant Metabolic Enzymes.

    PubMed

    Engqvist, Martin K M

    2016-01-01

    The biology of living organisms is determined by the action and interaction of a large number of individual gene products, each with specific functions. Discovering and annotating the function of gene products is key to our understanding of these organisms. Controlled experiments and bioinformatic predictions both contribute to functional gene annotation. For most species it is difficult to gain an overview of what portion of gene annotations are based on experiments and what portion represent predictions. Here, I survey the current state of experimental knowledge of enzymes and metabolism in Arabidopsis thaliana as well as eleven economically important crops and forestry trees - with a particular focus on reactions involving organic acids in central metabolism. I illustrate the limited availability of experimental data for functional annotation of enzymes in most of these species. Many enzymes involved in metabolism of citrate, malate, fumarate, lactate, and glycolate in crops and forestry trees have not been characterized. Furthermore, enzymes involved in key biosynthetic pathways which shape important traits in crops and forestry trees have not been characterized. I argue for the development of novel high-throughput platforms with which limited functional characterization of gene products can be performed quickly and relatively cheaply. I refer to this approach as systems-level experimental characterization. The data collected from such platforms would form a layer intermediate between bioinformatic gene function predictions and in-depth experimental studies of these functions. Such a data layer would greatly aid in the pursuit of understanding a multiplicity of biological processes in living organisms.

  15. Rendering the "Not-So-Simple" Pendulum Experimentally Accessible.

    ERIC Educational Resources Information Center

    Jackson, David P.

    1996-01-01

    Presents three methods for obtaining experimental data related to acceleration of a simple pendulum. Two of the methods involve angular position measurements and the subsequent calculation of the acceleration while the third method involves a direct measurement of the acceleration. Compares these results with theoretical calculations and…

  16. [Experimental psychological research on the level of pretensions in alcoholics taking the sex factor into account].

    PubMed

    Meerzon, M M

    1987-01-01

    An experimental psychological study has involved 50 males and 53 females with Stage I-II alcoholism during their first hospitalization. The studied patients presented an extravert-neurotic type of personality degradation. Abnormalities of motivational activity in an experimental situation of choice were characterized by a very low level of pretensions in male alcoholics and the maximum level of pretensions in female alcoholics. An analysis of intellectual productivity of the patients has indicated a low intellectual output and inability of the rational utilization of the intellectual potential. In view of the heterogeneity of affective disturbances in men and women, the author recommends a differential psychotherapeutical approach to alcoholic patients of different sex.

  17. IR-IR Conformation Specific Spectroscopy of Na +(Glucose) Adducts

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

    Voss, Jonathan M.; Kregel, Steven J.; Fischer, Kaitlyn C.

    Here in this paper we report an IR-IR double resonance study of the structural landscape present in the Na +(glucose) complex. Our experimental approach involves minimal modifications to a typical IR predissociation setup, and can be carried out via ion-dip or isomer-burning methods, providing additional flexibility to suit different experimental needs. In the current study, the single-laser IR predissociation spectrum of Na +(glucose), which clearly indicates contributions from multiple structures, was experimentally disentangled to reveal the presence of three α-conformers and five β-conformers. Comparisons with calculations show that these eight conformations correspond to the lowest energy gas-phase structures with distinctivemore » Na+ coordination.« less

  18. IR-IR Conformation Specific Spectroscopy of Na +(Glucose) Adducts

    DOE PAGES

    Voss, Jonathan M.; Kregel, Steven J.; Fischer, Kaitlyn C.; ...

    2017-09-27

    Here in this paper we report an IR-IR double resonance study of the structural landscape present in the Na +(glucose) complex. Our experimental approach involves minimal modifications to a typical IR predissociation setup, and can be carried out via ion-dip or isomer-burning methods, providing additional flexibility to suit different experimental needs. In the current study, the single-laser IR predissociation spectrum of Na +(glucose), which clearly indicates contributions from multiple structures, was experimentally disentangled to reveal the presence of three α-conformers and five β-conformers. Comparisons with calculations show that these eight conformations correspond to the lowest energy gas-phase structures with distinctivemore » Na+ coordination.« less

  19. Formative Peer Assessment in Primary School: The Effects of Involving Pupils in Setting Assessment Criteria on Their Appraisal and Feedback Style

    ERIC Educational Resources Information Center

    Leenknecht, Martijn J. M.; Prins, Frans J.

    2018-01-01

    This experimental study is aimed at examining the effect of involving pupils in primary education in setting assessment criteria and standards on their appraisal of a peer's work and their peer feedback style. It is expected that our intervention will lead to (1) a criteria-referenced appraisal and (2) more final vocabulary, which is associated…

  20. Coherent Extreme Ultraviolet Generation and Surface Studies Using Ultraviolet Excimer Lasers.

    DTIC Science & Technology

    1986-02-10

    of Outer-Shell Electrons" 7. "A Theoretical Model of Inner-Shell ......................... 30 A Excitation by Outer-Snell Electrons" E. "Anomalous...rays are feasible. Our work involves a program of activities, involving both experimental and theoretical components, to explore the physical... theoretical effort con- centrating on the character of high order multiquantum coupling in the inten- sity regime above 1017 WcM2 . In addition

  1. The Implications of Contamination for Educational Experiments with Two Levels of Nesting

    ERIC Educational Resources Information Center

    Rhoads, Christopher

    2016-01-01

    Experimental evaluations that involve the educational system usually involve a hierarchical structure (students are nested within classrooms that are nested within schools, etc.). Concerns about contamination, where research subjects receive certain features of an intervention intended for subjects in a different experimental group, have often led…

  2. Analysis of Lateral Rail Restraint.

    DOT National Transportation Integrated Search

    1983-09-01

    This report deals with the analysis of lateral rail strength using the results of experimental investigations and a nonlinear rail response model. Part of the analysis involves the parametric study of the influence of track parameters on lateral rail...

  3. Self-handicapping in school physical education: The influence of the motivational climate.

    PubMed

    Standage, Martyn; Treasure, Darren C; Hooper, Katherine; Kuczka, Kendy

    2007-03-01

    Self-handicapping is an attribution-related process whereby individuals create performance impediments/excuses to protect self-worth in socially evaluative environments. Thus, the prevailing motivational climate would appear to be an important factor when attempting to understand the situational self-handicapping process within school physical education. Drawing from achievement goal theory, the study examined the effect of experimentally induced conditions (viz. task vs. ego) on situational self-handicapping. Seventy British secondary school students (36 females and 34 males; M age = 11.98; SD=0.31). Participants were randomly assigned to partake in a running endurance task in either an ego-involving (20 male students and 16 female students) or a task-involving (14 male students and 20 female students) condition. Prior to completing the experimental task, participants were given the opportunity to claim situational self-handicaps. Data for goal orientations, subjective climate perceptions, perceived ability and perceived task importance were also obtained. After determining the effectiveness of the experimental manipulation, results revealed participants in the ego-involving condition to report significantly more situational self-handicapping claims. Further, and after controlling for individual difference variables, the results of moderated hierarchical regression analysis revealed subjective perceptions of an ego-involving climate to be the main positive predictor of situational self-handicapping. Although a weaker contributor to the percentage of variance explained, task orientation emerged as a negative predictor of situational self-handicapping. The findings suggest that PE teachers would be prudent to minimize ego-involving situations should they wish to reduce situational self-handicapping.

  4. An experimental study of mushroom shaped stall cells. [on finite wings with separated flow

    NASA Technical Reports Server (NTRS)

    Winkelmann, A. E.

    1982-01-01

    Surface patterns characterized by a pair of counter-rotating swirls have been observed in connection with the conduction of surface flow visualization experiments involving test geometries with separated flows. An example of this phenomenon occurring on a finite wing with trailing edge stall has been referred to by Winkelmann and Barlow (1980) as 'mushroom shaped'. A description is presented of a collection of experimental results which show or suggest the occurrence of mushroom shaped stall cells on a variety of test geometries. Investigations conducted with finite wings, airfoil models, and flat plates are considered, and attention is given to studies involving the use of bluff models, investigations of shock induced boundary layer separation, and mushroom shaped patterns observed in a number of miscellaneous cases. It is concluded that the mushroom shaped stall cell appears commonly in separated flow regions.

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

    PubMed

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

    2016-04-22

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

  6. Laminar Premixed and Diffusion Flames (Ground-Based Study)

    NASA Technical Reports Server (NTRS)

    Dai, Z.; El-Leathy, A. M.; Lin, K.-C.; Sunderland, P. B.; Xu, F.; Faeth, G. M.; Urban, D. L. (Technical Monitor); Yuan, Z.-G. (Technical Monitor)

    2000-01-01

    Ground-based studies of soot processes in laminar flames proceeded in two phases, considering laminar premixed flames and laminar diffusion flames, in turn. The test arrangement for laminar premixed flames involved round flat flame burners directed vertically upward at atmospheric pressure. The test arrangement for laminar jet diffusion flames involved a round fuel port directed vertically upward with various hydrocarbon fuels burning at atmospheric pressure in air. In both cases, coflow was used to prevent flame oscillations and measurements were limited to the flame axes. The measurements were sufficient to resolve soot nucleation, growth and oxidation rates, as well as the properties of the environment needed to evaluate mechanisms of these processes. The experimental methods used were also designed to maintain capabilities for experimental methods used in corresponding space-based experiments. This section of the report will be limited to consideration of flame structure for both premixed and diffusion flames.

  7. Exciton coupling in molecular crystals

    NASA Technical Reports Server (NTRS)

    Ake, R. L.

    1976-01-01

    The implications of perfect exciton coupling and molecular vibrations were investigated, as well as the effect they have on the lifetime of singlet and triplet excitons coupled in a limiting geometry. Crystalline bibenzyl, Cl4Hl4, provided a situation in which these mechanisms involving exciton coupling can be studied in the limit of perfect coupling between units due to the crystal's geometry. This geometry leads to a coupling between the two halves of the molecule resulting in a splitting of the molecular excited states. The study reported involves an experimental spectroscopic approach and begins with the purification of the bibenzyl. The principal experimental apparatus was an emission spectrometer. A closed cycle cryogenic system was used to vary the temperature of the sample between 20 K and 300 K. The desired results are the temperature-dependent emission spectra of the bibenzyl; in addition, the lifetimes and quantum yields measured at each temperature reveal the effect of competing radiationless processes.

  8. Small Independent Action Force (SIAF), Vegetation Classification Study

    DTIC Science & Technology

    1976-03-01

    CONTENTS I. INTRODUCTION 8 II. BACKGBCUND and PORPOSE 10 III. METHOD 16 A. EXPERIMENTAL DESIGN 16 B. SUBJECTS .’ 17 C. APPARATUS 17 D. STIMULUS...reliability of subjects will be obtained. 15 III. METHOD A. EXPERIMENTAL DESIGN . The experiment involved a continous stream of stimuli. Phase 1 stimuli...the attribute to be scaled. The subjecr must designate one of the pair as greater. No equality judgments are permitted. In order to obtain data from

  9. Assessment of an intervention to train teaching hospital care providers in quality management

    PubMed Central

    Francois, P; Vinck, D; Labarere, J; Reverdy, T; Peyrin, J

    2005-01-01

    Background: Successful implementation of continuous quality improvement (CQI) programs in hospitals remains rare in all countries, making it necessary to experiment with implementation methods while considering the cultural factors of resistance to change. Objective: To assess the impact of an educational intervention on involvement of clinical department staff in the quality process. Setting: Twelve voluntary clinical departments (six experimental and six controls) in a French 2000-bed university hospital comprising 40 clinical departments. Intervention: Three day training seminar to a group of 12–20 staff members from each department. Design: Quasi-experimental post-test only design study with control group conducted 12 months after the intervention with a questionnaire completed in a face-to-face interview. Subjects: 98 trained staff and 100 untrained staff from the six experimental departments and 100 staff from the six control departments. Principal measurements: Declared knowledge of the CQI methods and participation in quality management activities. Results: 286 people (96%) were involved in the study. More of the trained staff knew the CQI methods (62.4%) than staff in the control departments (16.5%) (adjusted odds ratio (ORa) = 10.6 (95% CI 4.97 to 22.62)). More trained staff also participated in quality improvement work groups than control department staff (76.3% v 14.0%; ORa = 27.4 (95% CI 11.6 to 64.4)). In the experimental departments the untrained staff's knowledge of CQI methods and their participation in work groups did not differ from that of control department staff. Conclusions: A continuing education intervention can involve care providers in CQI. Dissemination of knowledge from trained personnel to other staff members remains limited. PMID:16076785

  10. Internal Friction And Instabilities Of Rotors

    NASA Technical Reports Server (NTRS)

    Walton, J.; Artiles, A.; Lund, J.; Dill, J.; Zorzi, E.

    1992-01-01

    Report describes study of effects of internal friction on dynamics of rotors prompted by concern over instabilities in rotors of turbomachines. Theoretical and experimental studies described. Theoretical involved development of nonlinear mathematical models of internal friction in three joints found in turbomachinery - axial splines, Curvic(TM) splines, and interference fits between smooth cylindrical surfaces. Experimental included traction tests to determine the coefficients of friction of rotor alloys at various temperatures, bending-mode-vibration tests of shafts equipped with various joints and rotordynamic tests of shafts with axial-spline and interference-fit joints.

  11. Mechanistic insights into the rhenium-catalyzed alcohol-to-olefin dehydration reaction.

    PubMed

    Korstanje, Ties J; Jastrzebski, Johann T B H; Klein Gebbink, Robertus J M

    2013-09-23

    Rhenium-based complexes are powerful catalysts for the dehydration of various alcohols to the corresponding olefins. Here, we report on both experimental and theoretical (DFT) studies into the mechanism of the rhenium-catalyzed dehydration of alcohols to olefins in general, and the methyltrioxorhenium-catalyzed dehydration of 1-phenylethanol to styrene in particular. The experimental and theoretical studies are in good agreement, both showing the involvement of several proton transfers, and of a carbenium ion intermediate in the catalytic cycle. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Effects of Graphic Organiser on Students' Achievement in Algebraic Word Problems

    ERIC Educational Resources Information Center

    Owolabi, Josiah; Adaramati, Tobiloba Faith

    2015-01-01

    This study investigated the effects of graphic organiser and gender on students' academic achievement in algebraic word problem. Three research questions and three null hypotheses were used in guiding this study. Quasi experimental research was employed and Non-equivalent pre and post test design was used. The study involved the Senior Secondary…

  13. A Meta-Analysis of Referential Communication Studies: A Computer Readable Literature Review.

    ERIC Educational Resources Information Center

    Dickson, W. Patrick; Moskoff, Mary

    A computer-assisted analysis of studies on referential communication (giving directions/explanations) located 66 reports involving 80 experiments, 114 referential tasks, and over 6,200 individuals. The studies were entered into a statistical software package system (SPSS) and analyzed for characteristics of the subjects and experimental designs,…

  14. An Ethnographic Case Study of the Administrative Organization, Processes, and Behavior in a Model Comprehensive High School.

    ERIC Educational Resources Information Center

    Zimman, Richard N.

    Using ethnographic case study methodology (involving open-ended interviews, participant observation, and document analysis) theories of administrative organization, processes, and behavior were tested during a three-week observation of a model comprehensive (experimental) high school. Although the study is limited in its general application, it…

  15. Recent Experiments Involving Few-Nucleon Systems

    NASA Astrophysics Data System (ADS)

    Tornow, W.

    2014-08-01

    Recent experimental results are presented for reactions involving A = 3 to A = 6 nuclear systems. The emphasis is on unique data obtained at new experimental facilities. It is shown that the inertial confinement fusion facilities OMEGA and NIF provide a largely unexpected opportunity for experimental few-body physics to both obtain data of unprecedented quality and extend previous measurements to energies not accessible in the past. Whenever possible, data are compared to state-of-the-art theoretical calculations.

  16. Hypersonic nozzle/afterbody CFD code validation. I - Experimental measurements

    NASA Technical Reports Server (NTRS)

    Spaid, Frank W.; Keener, Earl R.

    1993-01-01

    This study was conducted to obtain a detailed experimental description of the flow field created by the interaction of a single-expansion-ramp-nozzle flow with a hypersonic external stream. Data were obtained from a generic nozzle/afterbody model in the 3.5-Foot Hypersonic Wind Tunnel of the NASA Ames Research Center in a cooperative experimental program involving Ames and the McDonnell Douglas Research Laboratories. This paper presents experimental results consisting primarily of surveys obtained with a five-hole total-pressure/flow-direction probe and a total-temperature probe. These surveys were obtained in the flow field created by the interaction between the underexpanded jet plume and the external flow.

  17. Effect of herd cues and product involvement on bidder online choices.

    PubMed

    Chen, Yi-Fen; Wang, Ya-Ju

    2010-08-01

    Previous works have shown that consumers are influenced by others in decision making. Herd behavior is common in situations in which consumers infer product quality from other consumer choices and incorporate that information into their own decision making. This research presents two studies examining herd effect and the moderating role of product involvement on bidder choices in online auctions. The two studies addressed the influence on bidder online choices of herd cues frequently found in online auctions, including feedback ratings and number of questions and answers. The experimental results demonstrated that bidders use online herd cues when making decisions in online auctions. Additionally, the effects of herd cues on bidder online choices were stronger in high-involvement than low-involvement participants. Results and implications are discussed.

  18. Teaching Grade 5 Life Science with a Case Study Approach

    ERIC Educational Resources Information Center

    Olgun, Ozlem Sila; Adali, Belgin

    2008-01-01

    The main purpose of this study was to investigate the effects of a case study approach on students' achievement and attitudes towards viruses, bacteria, fungi, and protista. Fifth-grade students (N = 88) from two different classes were involved in the study. One intact class was assigned as the experimental group, whereas the other intact class…

  19. Efficacy of Visual-Acoustic Biofeedback Intervention for Residual Rhotic Errors: A Single-Subject Randomization Study

    ERIC Educational Resources Information Center

    Byun, Tara McAllister

    2017-01-01

    Purpose: This study documented the efficacy of visual-acoustic biofeedback intervention for residual rhotic errors, relative to a comparison condition involving traditional articulatory treatment. All participants received both treatments in a single-subject experimental design featuring alternating treatments with blocked randomization of…

  20. A comparative study of air traffic trainee aptitude-test measures involving Navy, Marine Corps and FAA controllers.

    DOT National Transportation Integrated Search

    1968-09-01

    The study concerns the experimental use of several commercially-published aptitude tests and a determination of their validity as predictors of training-performance grades for more than 300 Marines and over 600 Naval students who entered a basic air-...

  1. Impact of a Technology-Mediated Reading Intervention on Adolescents' Reading Comprehension

    ERIC Educational Resources Information Center

    Fogarty, Melissa; Clemens, Nathan; Simmons, Deborah; Anderson, Leah; Davis, John; Smith, Ashley; Wang, Huan; Kwok, Oi-man; Simmons, Leslie E.; Oslund, Eric

    2017-01-01

    In this experimental study we examined the effects of a technology-mediated, multicomponent reading comprehension intervention, Comprehension Circuit Training (CCT), for middle school students, the majority of whom were struggling readers. The study was conducted in three schools, involving three teachers and 228 students. Using a within-teacher…

  2. DYNAMIC ENERGY SAVING IN BUILDINGS WITH UNDERFLOOR AIR DISTRIBUTION SYSTEM – EXPERIMENTAL AND SIMULATION STUDIES

    EPA Science Inventory

    The present study is aimed at seeking a better understanding of the thermodynamics involved with the air distribution strategies associated with UFAD systems and its impact on the energy saving dynamics.
    Thus objectives are:

    • Experiment...

    • Effects of Individual Development Accounts (IDAs) on Household Wealth and Saving Taste

      ERIC Educational Resources Information Center

      Huang, Jin

      2010-01-01

      This study examines effects of individual development accounts (IDAs) on household wealth of low-income participants. Methods: This study uses longitudinal survey data from the American Dream Demonstration (ADD) involving experimental design (treatment group = 537, control group = 566). Results: Results from quantile regression analysis indicate…

    • Attributing Responsibility for Child Maltreatment when Domestic Violence Is Present

      ERIC Educational Resources Information Center

      Landsman, Miriam J.; Hartley, Carolyn Copps

      2007-01-01

      Objective: The purpose of this study was to examine factors that influence how child welfare workers attribute responsibility for child maltreatment and child safety in cases involving domestic violence. Methods: The study used a factorial survey approach, combining elements of survey research with an experimental design. Case vignettes were…

    • The physics of sub-critical lattices in accelerator driven hybrid systems: The MUSE experiments in the MASURCA facility

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

      Chauvin, J. P.; Lebrat, J. F.; Soule, R.

      Since 1991, the CEA has studied the physics of hybrid systems, involving a sub-critical reactor coupled with an accelerator. These studies have provided information on the potential of hybrid systems to transmute actinides and, long lived fission products. The potential of such a system remains to be proven, specifically in terms of the physical understanding of the different phenomena involved and their modelling, as well as in terms of experimental validation of coupled systems, sub-critical environment/accelerator. This validation must be achieved through mock-up studies of the sub-critical environments coupled to a source of external neutrons. The MUSE-4 mock-up experiment ismore » planed at the MASURCA facility and will use an accelerator coupled to a tritium target. The great step between the generator used in the past and the accelerator will allow to increase the knowledge in hybrid physic and to decrease the experimental biases and the measurement uncertainties.« less

    • Experimental and computational fluid dynamic studies of mixing for complex oral health products

      NASA Astrophysics Data System (ADS)

      Garcia, Marti Cortada; Mazzei, Luca; Angeli, Panagiota

      2015-11-01

      Mixing high viscous non-Newtonian fluids is common in the consumer health industry. Sometimes this process is empirical and involves many pilot plants trials which are product specific. The first step to study the mixing process is to build on knowledge on the rheology of the fluids involved. In this research a systematic approach is used to validate the rheology of two liquids: glycerol and a gel formed by polyethylene glycol and carbopol. Initially, the constitutive equation is determined which relates the viscosity of the fluids with temperature, shear rate, and concentration. The key variable for the validation is the power required for mixing, which can be obtained both from CFD and experimentally using a stirred tank and impeller of well-defined geometries at different impeller speeds. A good agreement between the two values indicates a successful validation of the rheology and allows the CFD model to be used for the study of mixing in the complex vessel geometries and increased sizes encountered during scale up.

    • Biosorption of Ag(I) from aqueous solutions by Klebsiella sp. 3S1.

      PubMed

      Muñoz, Antonio Jesús; Espínola, Francisco; Ruiz, Encarnación

      2017-05-05

      This study investigated the potential ability of Klebsiella sp. 3S1 to remove silver cations from aqueous solutions. The selected strain is a ubiquitous bacterium selected from among several microorganisms that had been isolated from wastewaters. To optimise the operating conditions in the biosorption process, a Rotatable Central Composite Experimental Design was developed establishing pH, temperature and biomass concentration as independent variables. Interaction mechanisms involved were analysed through kinetic and equilibrium studies. The experimental results suit pseudo-second order kinetics with two biosorption stages, being the first almost instantly. The Langmuir equilibrium model predicted a maximum capacity of biosorption (q) of 114.1mg Ag/g biomass. The study of the mechanisms involved in the biosorption was completed by employing advanced techniques which revealed that both bacterium-surface interactions and intracellular bioaccumulation participate in silver removal from aqueous solutions. The ability of Klebsiella sp. 3S1 to form silver chloride nanoparticles with interesting potential applications was also discussed. Copyright © 2017 Elsevier B.V. All rights reserved.

    • Technical, analytical and computer support

      NASA Technical Reports Server (NTRS)

      1972-01-01

      The development of a rigorous mathematical model for the design and performance analysis of cylindrical silicon-germanium thermoelectric generators is reported that consists of two parts, a steady-state (static) and a transient (dynamic) part. The material study task involves the definition and implementation of a material study that aims to experimentally characterize the long term behavior of the thermoelectric properties of silicon-germanium alloys as a function of temperature. Analytical and experimental efforts are aimed at the determination of the sublimation characteristics of silicon germanium alloys and the study of sublimation effects on RTG performance. Studies are also performed on a variety of specific topics on thermoelectric energy conversion.

    • Variation in teenage mothers' experiences of child care and other components of welfare reform: selection processes and developmental consequences.

      PubMed

      Yoshikawa, H; Rosman, E A; Hsueh, J

      2001-01-01

      Developmental evaluations of the current wave of welfare reform programs present challenges with regard to (1) assessing child outcomes; (2) accounting for heterogeneity among low-income families in both baseline characteristics and involvement in self-sufficiency activities and supports, and (3) development of alternatives to experimental approaches to causal inference. This study (N = 1,079) addresses these challenges by examining effects on 4- to 6-year-old children of different patterns of child care, self-sufficiency activities, and other service utilization indicators among experimental-group mothers in a 16-site welfare reform program. Outcomes in areas of cognitive ability and behavior problems were investigated. The study identified seven subgroups of participants engaging in different patterns of service utilization and activity involvement. A two-stage simultaneous equation methodology was used to account for selection, and effects on child cognitive ability of participation in specific patterns of services and activities were found. For example, children of mothers characterized by high levels of involvement in center-based child care, education, and job training showed higher levels of cognitive ability than children of mothers in groups characterized by high involvement in center-based care and education, or center-based care and job training. In addition, children of mothers in groups with high levels of involvement in any of these activities showed higher levels of cognitive ability than those with low levels of involvement. The bulk of selection effects occurred through site-level differences, rather than family-level socio-economic status or maternal depression indicators. Implications for welfare reform program and policy concerns are discussed.

    • Effect of microstructure on the static and dynamic behavior of recycled asphalt material

      DOT National Transportation Integrated Search

      2004-02-01

      This report describes the third year's research activities of a project dealing with the micromechanical behavior of asphalt materials. The project involved both theoretical/numerical modeling and experimental studies that were applied to investigate...

    • INTERACTIONS BETWEEN ORGANIC COMPOUNDS AND CYCLODEXTRIN-CLAY SYSTEMS

      EPA Science Inventory

      Computational and experimental techniques are combined in order to better understand interactions involving organic compounds and cyclodextrin (CD)-clay systems. CD-clay systems may have great potential in the containment of organic contaminants in the environment. This study w...

    • A randomized controlled trial of an intervention program to Brazilian mothers who use corporal punishment.

      PubMed

      Santini, Paolla Magioni; Williams, Lucia C A

      2017-09-01

      This study evaluated a positive parenting program to Brazilian mothers who used corporal punishment with their children. The intervention was conducted in four agencies serving vulnerable children, and at a home replica laboratory at the University. Mothers who admitted using corporal punishment were randomly assigned between experimental (n=20) and control group (n=20). The program consisted of 12 individual sessions using one unit from Projeto Parceria (Partnership Project), with specific guidelines and materials on positive parenting, followed by observational sessions of mother-child interaction with live coaching and a video feedback session in the lab. The study used an equivalent group experimental design with pre/post-test and follow-up, in randomized controlled trials. Measures involved: Initial Interview; Strengths and Difficulties Questionnaire (SDQ) - parent and child versions; Beck Depression Inventory (BDI); observational sessions with a protocol; and a Program Evaluation by participants. Analysis of mixed models for repeated measures revealed significant positive effects on the BDI and SDQ total scores, as well as less Conduct problems and Hyperactivity in SDQ measures from the experimental group mothers, comparing pre with post-test. Observational data also indicated significant improvement in positive interaction from the experimental group mothers at post-test, in comparison with controls. No significant results were found, however, in children's observational measures. Limitations of the study involved using a restricted sample, among others. Implications for future research are suggested. Copyright © 2017 Elsevier Ltd. All rights reserved.

    • E-Learning System for Experiments Involving Construction of Practical Electronic Circuits

      ERIC Educational Resources Information Center

      Takemura, Atsushi

      2013-01-01

      This paper proposes a novel e-learning system for technical experiments involving the construction of practical electronic circuits; this system would meet the various demands of individual experimenters. This mixed mode is beneficial for practical use in that an experimenter who does not have sufficient circuit components for circuit making can…

    • CXCR3/CXCL10 Axis Regulates Neutrophil-NK Cell Cross-Talk Determining the Severity of Experimental Osteoarthritis.

      PubMed

      Benigni, Giorgia; Dimitrova, Petya; Antonangeli, Fabrizio; Sanseviero, Emilio; Milanova, Viktoriya; Blom, Arjen; van Lent, Peter; Morrone, Stefania; Santoni, Angela; Bernardini, Giovanni

      2017-03-01

      Several immune cell populations are involved in cartilage damage, bone erosion, and resorption processes during osteoarthritis. The purpose of this study was to investigate the role of NK cells in the pathogenesis of experimental osteoarthritis and whether and how neutrophils can regulate their synovial localization in the disease. Experimental osteoarthritis was elicited by intra-articular injection of collagenase in wild type and Cxcr3 -/- 8-wk old mice. To follow osteoarthritis progression, cartilage damage, synovial thickening, and osteophyte formation were measured histologically. To characterize the inflammatory cells involved in osteoarthritis, synovial fluid was collected early after disease induction, and the cellular and cytokine content were quantified by flow cytometry and ELISA, respectively. We found that NK cells and neutrophils are among the first cells that accumulate in the synovium during osteoarthritis, both exerting a pathogenic role. Moreover, we uncovered a crucial role of the CXCL10/CXCR3 axis, with CXCL10 increasing in synovial fluids after injury and Cxcr3 -/- mice being protected from disease development. Finally, in vivo depletion experiments showed that neutrophils are involved in an NK cell increase in the synovium, possibly by expressing CXCL10 in inflamed joints. Thus, neutrophils and NK cells act as important disease-promoting immune cells in experimental osteoarthritis and their functional interaction is promoted by the CXCL10/CXCR3 axis. Copyright © 2017 by The American Association of Immunologists, Inc.

    • Theoretical and Experimental Studies in Reactive Scattering.

      DTIC Science & Technology

      1986-08-11

      dynamics 3. Three-dimensional reaction dynamics 4. Anisotropic potentials for He + C02, OCS, CS2 .. 5. Production of a high intensity-high energy beam of...involving beams of He atoms, H atoms and metastable H molecules aimed at the determination of potential energy surfaces involving these systems. 2... energy of 0.3 ’, Kcal/mole below the top of the barrier, the reaction probability from ground S"t vibrational state reagent to ground vibrational

    • Investigation of Compressibility Effect for Aeropropulsive Shear Flows

      NASA Technical Reports Server (NTRS)

      Balasubramanyam, M. S.; Chen, C. P.

      2005-01-01

      Rocket Based Combined Cycle (RBCC) engines operate within a wide range of Mach numbers and altitudes. Fundamental fluid dynamic mechanisms involve complex choking, mass entrainment, stream mixing and wall interactions. The Propulsion Research Center at the University of Alabama in Huntsville is involved in an on- going experimental and numerical modeling study of non-axisymmetric ejector-based combined cycle propulsion systems. This paper attempts to address the modeling issues related to mixing, shear layer/wall interaction in a supersonic Strutjet/ejector flow field. Reynolds Averaged Navier-Stokes (RANS) solutions incorporating turbulence models are sought and compared to experimental measurements to characterize detailed flow dynamics. The effect of compressibility on fluids mixing and wall interactions were investigated using an existing CFD methodology. The compressibility correction to conventional incompressible two- equation models is found to be necessary for the supersonic mixing aspect of the ejector flows based on 2-D simulation results. 3-D strut-base flows involving flow separations were also investigated.

    • Human experimental anxiety: actual public speaking induces more intense physiological responses than simulated public speaking.

      PubMed

      Zuardi, Antonio Waldo; Crippa, José Alexandre de Souza; Hallak, Jaime Eduardo Cecílio; Gorayeb, Ricardo

      2013-01-01

      a) To perform a systematic and meta-analytic review to verify whether the Simulated Public Speaking Task (SPST) leads to a greater increase in self-rated anxiety than in physiological correlates of anxiety; and b) to compare the results obtained with the SPST with an actual public speaking task involving healthy volunteers. a) The PubMed and ISI Web of Knowledge databases were searched for studies involving the SPST prior to 2012. Eleven publications were eligible and provided data from 143 healthy volunteers for meta-analysis; b) 48 university students without somatic or psychiatric disorders were divided into three experimental groups of 16 subjects to undergo one of the following: SPST, real-world public speaking task (real-world), and control situation (control). The meta-analysis showed that the SPST induced a significant increase in the Visual Analogue Mood Scale (VAMS) anxiety factor, but no significant increases in systolic blood pressure or heart rate. The empirical study showed that the real-world public speaking task increased heart rate, systolic blood pressure and diastolic blood pressure significantly more than the control and SPST conditions. These results suggest that real public speaking might be better than SPST in inducing experimental anxiety.

    • The Role of Binding Site on the Mechanical Unfolding Mechanism of Ubiquitin

      NASA Astrophysics Data System (ADS)

      Cao, Penghui; Yoon, Gwonchan; Tao, Weiwei; Eom, Kilho; Park, Harold S.

      2015-03-01

      We apply novel atomistic simulations based on potential energy surface exploration to investigate the constant force-induced unfolding of ubiquitin. At the experimentally-studied force clamping level of 100 pN, we find a new unfolding mechanism starting with the detachment between β5 and β3 involving the binding site of ubiquitin, the Ile44 residue. This new unfolding pathway leads to the discovery of new intermediate configurations, which correspond to the end-to-end extensions previously seen experimentally. More importantly, it demonstrates the novel finding that the binding site of ubiquitin can be responsible not only for its biological functions, but also its unfolding dynamics. We also report in contrast to previous single molecule constant force experiments that when the clamping force becomes smaller than about 300 pN, the number of intermediate configurations increases dramatically, where almost all unfolding events at 100 pN involve an intermediate configuration. By directly calculating the life times of the intermediate configurations from the height of the barriers that were crossed on the potential energy surface, we demonstrate that these intermediate states were likely not observed experimentally due to their lifetimes typically being about two orders of magnitude smaller than the experimental temporal resolution.

    • Effects of Testwiseness Training in Mathematics on Adolescent Secondary School Students' Test Anxiety in Ondo State, Nigeria

      ERIC Educational Resources Information Center

      Gbore, Lawrence Olu; Osakuade, Joseph Oluwatayo

      2016-01-01

      This study investigated the effects of test-wiseness training in Mathematics on adolescent secondary school students' test anxiety. The research study adopted for the study was an experimental research that involved pretest, posttest and control groups design. One hundred and twenty (120) adolescent senior secondary school class three students of…

    • An Exploratory Comparison of Traditional Classroom Instruction and Anchored Instruction with Secondary School Students: Turkish Experience

      ERIC Educational Resources Information Center

      Elcin, Melih; Sezer, Baris

      2014-01-01

      The purpose of this study was to investigate the impact of anchored instruction on the students in secondary school math studies classrooms. This study adopted a quasi-experimental design. This research involved both quantitative and qualitative methods to investigate the effects of anchored instruction on students' academical achievement,…

  1. Effect of Using Mathematics Laboratory in Teaching Mathematics on the Achievement of Mathematics Students

    ERIC Educational Resources Information Center

    Okigbo, Ebele C.; Osuafor, Abigail M.

    2008-01-01

    The study investigated the effect of using mathematics laboratory in teaching on students' achievement in Junior Secondary School Mathematics. A total of 100 JS 3 Mathematics students were involved in the study. The study is a quasi-experimental research. Results were analyzed using mean, standard deviation and analysis of covariance (ANCOVA).…

  2. Enhancing Vocabulary and Writing Skills through Digital Storytelling in Higher Education

    ERIC Educational Resources Information Center

    Tajeri, Mojtaba; Syal, Pushpinder; Marzban, Sanaz

    2017-01-01

    The purpose of this study was to examine the benefits of using Digital Storytelling (DST) in language classes in higher education. The study also aims to explore the appropriate classroom activities which assist language teaching and learning. The thirteen-week study adopted a pretest and posttest quasi-experimental design involving a group of 20…

  3. The Effect of Environmental Science Projects on Students' Environmental Knowledge and Science Attitudes

    ERIC Educational Resources Information Center

    Al-Balushi, Sulaiman M.; Al-Aamri, Shamsa S.

    2014-01-01

    The current study explores the effectiveness of involving students in environmental science projects for their environmental knowledge and attitudes towards science. The study design is a quasi-experimental pre-post control group design. The sample was 62 11th-grade female students studying at a public school in Oman. The sample was divided into…

  4. Urban pedestrian accident countermeasures experimental evaluation. Volume 2, Accident studies

    DOT National Transportation Integrated Search

    1975-02-01

    A pedestrian accident data collection system was established in six major cities. The system involved using the regular police accident report form and a specifically designed supplementary data form. The information on the forms was combined, and th...

  5. Air pollution and neuroendocrine stress-mediated systemic metabolic and inflammatory response

    EPA Science Inventory

    New experimental evidence involving the role of neuroendocrine activation challenges an accepted mechanistic paradigm of how irritant air pollutants induce systemic metabolic impairment and lung injury/inflammation. We focus on recent air pollution studies highlighting how the re...

  6. Detection of glass particles on bone lesions using SEM-EDS.

    PubMed

    Montoriol, Romain; Guilbeau-Frugier, Céline; Chantalat, Elodie; Roumiguié, Mathieu; Delisle, Marie-Bernadette; Payré, Bruno; Telmon, Norbert; Savall, Frédéric

    2017-09-01

    The problem of identifying the wounding agent in forensic cases is recurrent. Moreover, when several tools are involved, distinguishing the origin of lesions can be difficult. Scanning electron microscopy (SEM)/energy dispersive X-ray analysis (EDS) equipment is increasingly available to the scientific and medical community, and some studies have reported its use in forensic anthropology. However, at our knowledge, no study has reported the use of SEM-EDS in forensic cases involving glass tools, whether in case reports or experiments. We performed an experimental study on human rib fragments, on which we manually created wounds using fragments of window and mirror glass. SEM-EDS was executed on samples without any further preparation on low vacuum mode, then on the same samples after defleshing them completely by boiling them. Window and mirror glass particles were detected on experimental wounds. Both had silica in their spectra, and the opaque side of the mirror contained titanium, allowing for their identification. Boiling and defleshing the bone samples involved a loss of information in terms of the number of wounds detected as positive for glass particles and in the number of glass particles detected, for both window and mirror glass. We suggest the analysis of wounds with suspected glass particles using low vacuum mode and with no defleshment by boiling.

  7. Cardiac microvascular rarefaction in hyperthyroidism-induced left ventricle dysfunction.

    PubMed

    Freitas, Felipe; Estato, Vanessa; Carvalho, Vinícius Frias; Torres, Rafael Carvalho; Lessa, Marcos Adriano; Tibiriçá, Eduardo

    2013-10-01

    The pathophysiology underlying hyperthyroidism-induced left ventricle (LV) dysfunction and hypertrophy directly involves the heart and indirectly involves the neuroendocrine systems. The effects of hyperthyroidism on the microcirculation are still controversial in experimental models. We investigated the effects of hyperthyroidism on the cardiac function and microcirculation of an experimental rat model. Male Wistar rats (170-250 g) were divided into two groups: the euthyroid group (n = 10), which was treated with 0.9% saline solution, and the hyperthyroid group (n = 10), which was treated with l-thyroxine (600 μg/kg/day, i.p.) during 14 days. An echocardiographic study was performed to evaluate the alterations in cardiac function, structure and geometry. The structural capillary density and the expression of angiotensin II AT1 receptor in the LV were analyzed using histochemistry and immunohistochemistry, respectively. Hyperthyroidism was found to induce profound cardiovascular alterations, such as systolic hypertension, tachycardia, LV dysfunction, cardiac hypertrophy, and myocardial fibrosis. This study demonstrates the existence of structural capillary rarefaction and the down-regulation of the cardiac angiotensin II AT1 receptor in the myocardium of hyperthyroid rats in comparison with euthyroid rats. Microvascular rarefaction may be involved in the pathophysiology of hyperthyroidism-induced cardiovascular alterations. © 2013 John Wiley & Sons Ltd.

  8. Thermal barrier coating life prediction model development

    NASA Technical Reports Server (NTRS)

    Demasi, J. T.

    1986-01-01

    A methodology is established to predict thermal barrier coating life in a environment similar to that experienced by gas turbine airfoils. Experiments were conducted to determine failure modes of the thermal barrier coating. Analytical studies were employed to derive a life prediction model. A review of experimental and flight service components as well as laboratory post evaluations indicates that the predominant mode of TBC failure involves thermomechanical spallation of the ceramic coating layer. This ceramic spallation involves the formation of a dominant crack in the ceramic coating parallel to and closely adjacent to the topologically complex metal ceramic interface. This mechanical failure mode clearly is influenced by thermal exposure effects as shown in experiments conducted to study thermal pre-exposure and thermal cycle-rate effects. The preliminary life prediction model developed focuses on the two major damage modes identified in the critical experiments tasks. The first of these involves a mechanical driving force, resulting from cyclic strains and stresses caused by thermally induced and externally imposed mechanical loads. The second is an environmental driving force based on experimental results, and is believed to be related to bond coat oxidation. It is also believed that the growth of this oxide scale influences the intensity of the mechanical driving force.

  9. Simulating maar-diatreme volcanic systems in bench-scale experiments

    NASA Astrophysics Data System (ADS)

    Andrews, R. G.; White, J. D. L.; Dürig, T.; Zimanowski, B.

    2015-12-01

    Maar-diatreme eruptions are incompletely understood, and explanations for the processes involved in them have been debated for decades. This study extends bench-scale analogue experiments previously conducted on maar-diatreme systems and attempts to scale the results up to both field-scale experimentation and natural volcanic systems in order to produce a reconstructive toolkit for maar volcanoes. These experimental runs produced via multiple mechanisms complex deposits that match many features seen in natural maar-diatreme deposits. The runs include deeper single blasts, series of descending discrete blasts, and series of ascending blasts. Debris-jet inception and diatreme formation are indicated by this study to involve multiple types of granular fountains within diatreme deposits produced under varying initial conditions. The individual energies of blasts in multiple-blast series are not possible to infer from the final deposits. The depositional record of blast sequences can be ascertained from the proportion of fallback sedimentation versus maar ejecta rim material, the final crater size and the degree of overturning or slumping of accessory strata. Quantitatively, deeper blasts involve a roughly equal partitioning of energy into crater excavation energy versus mass movement of juvenile material, whereas shallower blasts expend a much greater proportion of energy in crater excavation.

  10. Experiments: Why and How?

    PubMed

    Hansson, Sven Ove

    2016-06-01

    An experiment, in the standard scientific sense of the term, is a procedure in which some object of study is subjected to interventions (manipulations) that aim at obtaining a predictable outcome or at least predictable aspects of the outcome. The distinction between an experiment and a non-experimental observation is important since they are tailored to different epistemic needs. Experimentation has its origin in pre-scientific technological experiments that were undertaken in order to find the best technological means to achieve chosen ends. Important parts of the methodological arsenal of modern experimental science can be traced back to this pre-scientific, technological tradition. It is claimed that experimentation involves a unique combination of acting and observing, a combination whose unique epistemological properties have not yet been fully clarified.

  11. Design, Construction and Testing of Annular Diffusers for High Speed Civil Transportation Combustor Applications

    NASA Technical Reports Server (NTRS)

    Okhio, Cyril B.

    1996-01-01

    A theoretical and an experimental design study of subsonic flow through curved-wall annular diffusers has been initiated under this award in order to establish the most pertinent design parameters and hence performance characteristics for such devices, an the implications of their application in the design of engine components in the aerospace industries. The diffusers under this study are expected to contain appreciable regions of stall and the effects of swirl on their performance are being studied. The experimental work involves the application of Computer Aided Design software tool to the development of a suitable annular diffuse geometry and the subsequent downloading of such data to a CNC machine at Central State University (CSU). Two experimental run segments have been completed so far during FY-95 involving flow visualization and diffuser performance evaluation based on Kinetic Energy Dissipation. The method of calculation of the performance of diffusers based on pressure recovery coefficient has been shown to have some shortcomings and so the kinetic energy dissipation approach has been introduced in the run segment two with some success. The application of the discretized, full Navier Stokes and Continuity equations to the numerical study of the problem described above for the time-mean flow is expected to follow. Various models of turbulence are being evaluated for adoption throughout the study and comparisons would be made with experimental data where they exist. Assessment of diffuser performance based on the dissipated mechanical energy would also be made. The result of the investigations are expected to indicate that more cost effective component design of such devices as diffusers which normally contain complex flows can still be achieved.

  12. A United Effort for Crystal Growth, Neutron Scattering, and X-ray Scattering Studies of Novel Correlated Electron Materials

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

    Lee, Young S.

    2015-02-12

    The research accomplishments during the award involved experimental studies of correlated electron systems and quantum magnetism. The techniques of crystal growth, neutron scattering, x-ray scattering, and thermodynamic & transport measurements were employed, and graduate students and postdoctoral research associates were trained in these techniques.

  13. Group-Based Life Design Counseling in an Italian Context

    ERIC Educational Resources Information Center

    Di Fabio, Annamaria; Maree, Jacobus Gideon

    2012-01-01

    This study examined the effectiveness of group-based Life Design Counseling using the Career-Story Interview. Written exercises were used to implement the seven topics in the Career-Story Interview. The present study employed an experimental design that involved two groups of Italian entrepreneurs from the agricultural and trade sectors, namely an…

  14. An Inexpensive High Pressure Optical Absorption Cell for IR-VIS-UV Studies.

    ERIC Educational Resources Information Center

    Rodgers, V. E.; Angell, C. A.

    1983-01-01

    Describes an optical cell, suitable for high-pressure studies between at least -130 and +150 degrees Celsius, which may be assembled for about $50. Discusses experimental demonstration of principles involved when using the apparatus, including effects of pressure on coordination of ions in solution and on reaction rates in solution. (JN)

  15. GUIDANCE FOR RESEARCH HOUSE STUDIES OF THE FLORIDA RADON RESEARCH PROGRAM, VOLUME 2: MODEL-BACKED EXPERIMENTAL PROTOCOL FOR DETERMINING RADON

    EPA Science Inventory

    The report provides guidance and a readily available reference to groups involved with the Florida Radon Research Program's (FRRP's) research house studies. It includes: 1): Lists of Parameters for continuous and periodic high and low resolution measurements; (2) Protocols for c...

  16. Observed Changes in Classroom Behavior Utilizing Supportive Intervention.

    ERIC Educational Resources Information Center

    Swift, J. Nathan; And Others

    The effects of instructional guides and wait-time feedback upon the classroom interaction of 40 middle school science teachers were investigated in a prior study. The experimental nature of that study produced an artificial situation involving little personal contact between teacher-participants and the research staff. Therefore, a subsample of 10…

  17. Emancipation from Affluenza: Leading Social Change in the Classroom

    ERIC Educational Resources Information Center

    Mattison, Merri

    2012-01-01

    The purpose of this quasi-experimental study was to determine if one's level of affluenza could be reduced through education and awareness. In particular, this study measured whether or not exposure to the benefits of community involvement, and the harm of overconsumption could alter the intentions that college students have regarding their…

  18. Cetacean vocal learning and communication.

    PubMed

    Janik, Vincent M

    2014-10-01

    The cetaceans are one of the few mammalian clades capable of vocal production learning. Evidence for this comes from synchronous changes in song patterns of baleen whales and experimental work on toothed whales in captivity. While baleen whales like many vocal learners use this skill in song displays that are involved in sexual selection, toothed whales use learned signals in individual recognition and the negotiation of social relationships. Experimental studies demonstrated that dolphins can use learned signals referentially. Studies on wild dolphins demonstrated how this skill appears to be useful in their own communication system, making them an interesting subject for comparative communication studies. Copyright © 2014. Published by Elsevier Ltd.

  19. Rotationally inelastic collisions of excited NaK and NaCs molecules with noble gas and alkali atom perturbers.

    PubMed

    Jones, J; Richter, K; Price, T J; Ross, A J; Crozet, P; Faust, C; Malenda, R F; Carlus, S; Hickman, A P; Huennekens, J

    2017-10-14

    We report measurements of rate coefficients at T ≈ 600 K for rotationally inelastic collisions of NaK molecules in the 2(A) 1 Σ + electronic state with helium, argon, and potassium atom perturbers. Several initial rotational levels J between 14 and 44 were investigated. Collisions involving molecules in low-lying vibrational levels (v = 0, 1, and 2) of the 2(A) 1 Σ + state were studied using Fourier-transform spectroscopy. Collisions involving molecules in a higher vibrational level, v = 16, were studied using pump/probe, optical-optical double resonance spectroscopy. In addition, polarization spectroscopy measurements were carried out to study the transfer of orientation in these collisions. Many, but not all, of the measurements were carried out in the "single-collision regime" where more than one collision is unlikely to occur within the lifetime of the excited molecule. The analysis of the experimental data, which is described in detail, includes an estimate of effects of multiple collisions on the reported rate coefficients. The most significant result of these experiments is the observation of a strong propensity for ΔJ = even transitions in collisions involving either helium or argon atoms; the propensity is much stronger for helium than for argon. For the initial rotational levels studied experimentally, almost all initial orientation is preserved in collisions of NaK 2(A) 1 Σ + molecules with helium. Roughly between 1/3 and 2/3 of the orientation is preserved in collisions with argon, and almost all orientation is destroyed in collisions with potassium atoms. Complementary measurements on rotationally inelastic collisions of NaCs 2(A) 1 Σ + with argon do not show a ΔJ = even propensity. The experimental results are compared with new theoretical calculations of collisions of NaK 2(A) 1 Σ + with helium and argon. The calculations are in good agreement with the absolute magnitudes of the experimentally determined rate coefficients and accurately reproduce the very strong propensity for ΔJ = even transitions in helium collisions and the less strong propensity for ΔJ = even transitions in argon collisions. The calculations also show that collisions with helium are less likely to destroy orientation than collisions with argon, in agreement with the experimental results.

  20. Rotationally inelastic collisions of excited NaK and NaCs molecules with noble gas and alkali atom perturbers

    NASA Astrophysics Data System (ADS)

    Jones, J.; Richter, K.; Price, T. J.; Ross, A. J.; Crozet, P.; Faust, C.; Malenda, R. F.; Carlus, S.; Hickman, A. P.; Huennekens, J.

    2017-10-01

    We report measurements of rate coefficients at T ≈ 600 K for rotationally inelastic collisions of NaK molecules in the 2(A)1Σ+ electronic state with helium, argon, and potassium atom perturbers. Several initial rotational levels J between 14 and 44 were investigated. Collisions involving molecules in low-lying vibrational levels (v = 0, 1, and 2) of the 2(A)1Σ+ state were studied using Fourier-transform spectroscopy. Collisions involving molecules in a higher vibrational level, v = 16, were studied using pump/probe, optical-optical double resonance spectroscopy. In addition, polarization spectroscopy measurements were carried out to study the transfer of orientation in these collisions. Many, but not all, of the measurements were carried out in the "single-collision regime" where more than one collision is unlikely to occur within the lifetime of the excited molecule. The analysis of the experimental data, which is described in detail, includes an estimate of effects of multiple collisions on the reported rate coefficients. The most significant result of these experiments is the observation of a strong propensity for ΔJ = even transitions in collisions involving either helium or argon atoms; the propensity is much stronger for helium than for argon. For the initial rotational levels studied experimentally, almost all initial orientation is preserved in collisions of NaK 2(A)1Σ+ molecules with helium. Roughly between 1/3 and 2/3 of the orientation is preserved in collisions with argon, and almost all orientation is destroyed in collisions with potassium atoms. Complementary measurements on rotationally inelastic collisions of NaCs 2(A)1Σ+ with argon do not show a ΔJ = even propensity. The experimental results are compared with new theoretical calculations of collisions of NaK 2(A)1Σ+ with helium and argon. The calculations are in good agreement with the absolute magnitudes of the experimentally determined rate coefficients and accurately reproduce the very strong propensity for ΔJ = even transitions in helium collisions and the less strong propensity for ΔJ = even transitions in argon collisions. The calculations also show that collisions with helium are less likely to destroy orientation than collisions with argon, in agreement with the experimental results.

  1. On use of ZPR research reactors and associated instrumentation and measurement methods for reactor physics studies

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

    Chauvin, J.P.; Blaise, P.; Lyoussi, A.

    2015-07-01

    The French atomic and alternative energies -CEA- is strongly involved in research and development programs concerning the use of nuclear energy as a clean and reliable source of energy and consequently is working on the present and future generation of reactors on various topics such as ageing plant management, optimization of the plutonium stockpile, waste management and innovative systems exploration. Core physics studies are an essential part of this comprehensive R and D effort. In particular, the Zero Power Reactor (ZPR) of CEA: EOLE, MINERVE and MASURCA play an important role in the validation of neutron (as well photon) physicsmore » calculation tools (codes and nuclear data). The experimental programs defined in the CEA's ZPR facilities aim at improving the calculation routes by reducing the uncertainties of the experimental databases. They also provide accurate data on innovative systems in terms of new materials (moderating and decoupling materials) and new concepts (ADS, ABWR, new MTR (e.g. JHR), GENIV) involving new fuels, absorbers and coolant materials. Conducting such interesting experimental R and D programs is based on determining and measuring main parameters of phenomena of interest to qualify calculation tools and nuclear data 'libraries'. Determining these parameters relies on the use of numerous and different experimental techniques using specific and appropriate instrumentation and detection tools. Main ZPR experimental programs at CEA, their objectives and challenges will be presented and discussed. Future development and perspectives regarding ZPR reactors and associated programs will be also presented. (authors)« less

  2. Highlights of Transient Plume Impingement Model Validation and Applications

    NASA Technical Reports Server (NTRS)

    Woronowicz, Michael

    2011-01-01

    This paper describes highlights of an ongoing validation effort conducted to assess the viability of applying a set of analytic point source transient free molecule equations to model behavior ranging from molecular effusion to rocket plumes. The validation effort includes encouraging comparisons to both steady and transient studies involving experimental data and direct simulation Monte Carlo results. Finally, this model is applied to describe features of two exotic transient scenarios involving NASA Goddard Space Flight Center satellite programs.

  3. Nuclear spectroscopic studies. Progress report

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

    Bingham, C.R.; Guidry, M.W.; Riedinger, L.L.

    1994-02-18

    The Nuclear Physics group at UTK is involved in heavy-ion physics including both nuclear structure and reaction mechanisms. During the last year experimental work has been in 3 broad areas: structure of nuclei at high angular momentum, structure of nuclei far from stability, and ultra-relativistic heavy-ion physics. Results in these areas are described in this document under: properties of high-spin states, study of low-energy levels of nuclei far from stability, and high-energy heavy-ion physics (PHENIX, etc.). Another important component of the work is theoretical interpretation of experimental results (Joint Institute for Heavy Ion Research).

  4. Utilization of variation theory in the classroom: Effect on students' algebraic achievement and motivation

    NASA Astrophysics Data System (ADS)

    Jing, Ting Jing; Tarmizi, Rohani Ahmad; Bakar, Kamariah Abu; Aralas, Dalia

    2017-01-01

    This study investigates the effect of utilizing Variation Theory Based Strategy on students' algebraic achievement and motivation in learning algebra. The study used quasi-experimental non-equivalent control group research design and involved 56 Form Two (Secondary Two) students in two classes (28 in experimental group, 28 in control group) in Malaysia The first class of students went through algebra class taught with Variation Theory Based Strategy (VTBS) while the second class of students experienced conventional teaching strategy. The instruments used for the study were a 24-item Algebra Test and 36-item Instructional Materials Motivation Survey. Result from analysis of Covariance indicated that experimental group students achieved significantly better test scores than control group. Result of Multivariate Analysis of Variance also shows evidences of significant effect of VTBS on experimental students' overall motivation in all the five subscales; attention, relevance, confidence, and satisfaction. These results suggested the utilization of VTBS would improve students' learning in algebra.

  5. Humane Science Projects: Suggestions for Biology Studies That Are Scientifically Educational and Ethically Non-Controversial.

    ERIC Educational Resources Information Center

    Balcombe, Jonathan P., Comp.

    This paper lists 35 studies in biology which can be tailored to suit the full range of student age groups and are designed to involve most or all of the key elements of the scientific process (study design, data collection and presentation, and experimental manipulation). Examples of some studies are: (1) study the growth of molds on food items…

  6. On probability-possibility transformations

    NASA Technical Reports Server (NTRS)

    Klir, George J.; Parviz, Behzad

    1992-01-01

    Several probability-possibility transformations are compared in terms of the closeness of preserving second-order properties. The comparison is based on experimental results obtained by computer simulation. Two second-order properties are involved in this study: noninteraction of two distributions and projections of a joint distribution.

  7. Adolescents' Civic and Organizational Activity: An Experimental Study.

    ERIC Educational Resources Information Center

    Dashkevich, O. V.; Slavgorodskaia, E. L.

    1995-01-01

    Reports on the attitudes of 175 Russian adolescents and their teachers toward civic and community service activities. Argues that economic and social crises have created negative attitudes towards community service. Finds that students who are involved in community activities are more optimistic. (CFR)

  8. The Impact of Intervention Methods on Emotional Intelligence

    ERIC Educational Resources Information Center

    Davis, Christopher M.

    2013-01-01

    This experimental study continued the exploration surrounding emotional intelligence (EI). Emotional intelligence was examined through past and present literature, instrumentation, didactic teaching methods employing EI concepts, and data analysis. The experiment involved participants from two sections of an undergraduate economics class at a…

  9. Orbital Energy Levels in Molecular Hydrogen. A Simple Approach.

    ERIC Educational Resources Information Center

    Willis, Christopher J.

    1988-01-01

    Described are the energetics involved in the formation of molecular hydrogen using concepts that should be familiar to students beginning the study of molecular orbital theory. Emphasized are experimental data on ionization energies. Included are two-electron atomic and molecular systems. (CW)

  10. EXPERIMENTAL INVESTIGATION OF CRITICAL FUNDAMENTAL ISSUES IN HAZARDOUS WASTE INCINERATION

    EPA Science Inventory

    The report gives results of a laboratory-scale program investigating several fundamental issues involved in hazardous waste incineration. The key experiment for each study was the measurement of waste destruction behavior in a sub-scale turbulent spray flame. (1) Atomization Qual...

  11. Applied statistics in agricultural, biological, and environmental sciences.

    USDA-ARS?s Scientific Manuscript database

    Agronomic research often involves measurement and collection of multiple response variables in an effort to understand the more complex nature of the system being studied. Multivariate statistical methods encompass the simultaneous analysis of all random variables measured on each experimental or s...

  12. Variable conductance heat pipe technology

    NASA Technical Reports Server (NTRS)

    Marcus, B. D.; Edwards, D. K.; Anderson, W. T.

    1973-01-01

    Research and development programs in variable conductance heat pipe technology were conducted. The treatment has been comprehensive, involving theoretical and/or experimental studies in hydrostatics, hydrodynamics, heat transfer into and out of the pipe, fluid selection, and materials compatibility, in addition to the principal subject of variable conductance control techniques. Efforts were not limited to analytical work and laboratory experimentation, but extended to the development, fabrication and test of spacecraft hardware, culminating in the successful flight of the Ames Heat Pipe Experiment on the OAO-C spacecraft.

  13. Studies of oscillatory combustion and fuel vaporization

    NASA Technical Reports Server (NTRS)

    Borman, G. L.; Myers, P. S.; Uyehara, O. A.

    1972-01-01

    Research projects involving oscillatory combustion and fuel vaporization are reported. Comparisons of experimental and theoretical droplet vaporization histories under ambient conditions such that the droplet may approach its thermodynamic critical point are presented. Experimental data on instantaneous heat transfer from a gas to a solid surface under conditions of oscillatory pressure with comparisons to an unsteady one-dimensional model are analyzed. Droplet size and velocity distribution in a spray as obtained by use of a double flash fluorescent method were investigated.

  14. Small sarcocysts can be a feature of experimental infections with Sarcocystis neurona merozoites.

    PubMed

    Marsh, Antoinette E; Chaney, Sarah B; Howe, Daniel K; Saville, William J; Reed, Stephen M

    2017-10-15

    Several reports indicate the presence of small tissue cysts associated with Sarcocystis neurona infections. Several failed attempts to develop tissue cysts in potential intermediate host using in vitro derived parasites originally isolated from horses with equine protozoal myeloencephalitis suggest that the experimental methods to achieve bradyzoites with those isolates was not possible. Those prior studies reported the lack of detectable sarcocysts based on histology and in vivo feeding trials. A recent report of successful production and detection of small sarcocysts triggered us to review archived tissues from earlier experimental infection studies. The retrospective review sought to determine if small sized sarcocysts were not detected due to their relatively smaller size and infrequency as compared to larger sized sarcocysts produced with other isolates in these experimental inoculation trials. Tissues from two prior in vivo inoculation studies, involving in vitro-produced parasites inoculated into laboratory-reared cats and raccoons, were re-examined by immunohistochemistry staining to more easily detect the tissue cysts. In the experimental cat study no small tissue cysts were seen, consistent with the original publication results. However, in the experimental raccoon study, one raccoon inoculated with an EPM-derived isolate, SN-UCD1, had small sarcocysts not reported in the original publication. This retrospective study suggests that much closer scrutiny of tissues, including the use of immunohistochemistry on tissue sections is required to detect the smaller S. neurona sarcocysts associated with the experimental inoculations of the isolates originally derived from horses with EPM. Published by Elsevier B.V.

  15. What's in a Trial? On the Importance of Distinguishing Between Experimental Lab Studies and Randomized Controlled Trials: The Case of Cognitive Bias Modification and Alcohol Use Disorders.

    PubMed

    Wiers, Reinout W; Boffo, Marilisa; Field, Matt

    2018-05-01

    Recently, the National Institutes of Health (NIH) redefined clinical trials to include any study involving behavioral or biomedical interventions. In line with a general framework from experimental medicine, we argue that it is crucial to distinguish between experimental laboratory studies aimed at revealing psychological mechanisms underlying behavior and randomized controlled trials (RCTs) in clinical samples aimed at testing the efficacy of an intervention. As an illustration, we reviewed the current state of the evidence on the efficacy of cognitive bias modification (CBM) interventions in alcohol use disorders. A recent meta-analysis "cast serious doubts on the clinical utility of CBM interventions for addiction." That analysis combined experimental laboratory studies and RCTs. We demonstrated that, when studies are differentiated regarding study type (experimental laboratory study or RCT), mode of delivery (controlled experiment or Internet), and population (healthy volunteers or patients), the following effects are found: (a) short-lived effects of CBM on drinking behavior in experimental laboratory studies in students, but only when the bias is successfully manipulated; (b) small but robust effects of CBM on treatment outcome when administered as an adjunct to established treatments in clinical settings in RCTs with alcohol-dependent patients; and (c) nonspecific effects (reduced drinking irrespective of condition) in RCTs of CBM administered online to problem drinkers. We discuss how CBM might be improved when it is better integrated into regular treatment, especially cognitive behavioral therapy, and we conclude that disregarding the difference between experimental laboratory studies and RCTs can lead to invalid conclusions.

  16. Field Monitoring of Experimental Hot Mix Asphalt Projects Placed in Massachusetts

    DOT National Transportation Integrated Search

    2017-06-30

    Since 2000, Massachusetts has been involved with numerous field trials of experimental hot mix asphalt mixtures. These experimental mixtures included several pilot projects using the Superpave mixture design methodology, utilization of warm mix aspha...

  17. A mobile phone based alarm system for supervising vital parameters in free moving rats.

    PubMed

    Kellermann, Kristine; Kreuzer, Matthias; Omerovich, Adem; Hoetzinger, Franziska; Kochs, Eberhard F; Jungwirth, Bettina

    2012-02-23

    Study protocols involving experimental animals often require the monitoring of different parameters not only in anesthetized, but also in free moving animals. Most animal research involves small rodents, in which continuously monitoring parameters such as temperature and heart rate is very stressful for the awake animals or simply not possible. Aim of the underlying study was to monitor heart rate, temperature and activity and to assess inflammation in the heart, lungs, liver and kidney in the early postoperative phase after experimental cardiopulmonary bypass involving 45 min of deep hypothermic circulatory arrest in rats. Besides continuous monitoring of heart rate, temperature and behavioural activity, the main focus was on avoiding uncontrolled death of an animal in the early postoperative phase in order to harvest relevant organs before autolysis would render them unsuitable for the assessment of inflammation. We therefore set up a telemetry-based system (Data Science International, DSI™) that continuously monitored the rat's temperature, heart rate and activity in their cages. The data collection using telemetry was combined with an analysis software (Microsoft excel™), a webmail application (GMX) and a text message-service. Whenever an animal's heart rate dropped below the pre-defined threshold of 150 beats per minute (bpm), a notification in the form of a text message was automatically sent to the experimenter's mobile phone. With a positive predictive value of 93.1% and a negative predictive value of 90.5%, the designed surveillance and alarm system proved a reliable and inexpensive tool to avoid uncontrolled death in order to minimize suffering and harvest relevant organs before autolysis would set in. This combination of a telemetry-based system and software tools provided us with a reliable notification system of imminent death. The system's high positive predictive value helped to avoid uncontrolled death and facilitated timely organ harvesting. Additionally we were able to markedly reduce the drop out rate of experimental animals, and therefore the total number of animals used in our study. This system can be easily adapted to different study designs and prove a helpful tool to relieve stress and more importantly help to reduce animal numbers.

  18. Blending Physical and Virtual Manipulatives: An Effort to Improve Students' Conceptual Understanding through Science Laboratory Experimentation

    ERIC Educational Resources Information Center

    Olympiou, Georgios; Zacharia, Zacharias C.

    2012-01-01

    This study aimed to investigate the effect of experimenting with physical manipulatives (PM), virtual manipulatives (VM), and a blended combination of PM and VM on undergraduate students' understanding of concepts in the domain of "Light and Color." A pre-post comparison study design was used for the purposes of this study that involved 70…

  19. Involvement and Making Movies: A Study of the Introduction of Movie Making to Poverty Boys. Final Report.

    ERIC Educational Resources Information Center

    Durkin, Roderick

    Advocates of movie making believe that it provides a non-ethnocentric experience that is inherently engaging and relatively free from the risk of failure. Disadvantaged teenage boys who were attending two experimental summer work camps participated in studies of two aspects of movie making. The first study evaluated three different techniques for…

  20. An Educational Study of the Barometric Effect of Cosmic Rays with a Geiger Counter

    ERIC Educational Resources Information Center

    Famoso, Barbara; La Rocca, Paola; Riggi, Francesco

    2005-01-01

    An educational study of the barometric effect of cosmic rays was carried out using an inexpensive experimental set-up that allowed for long-term monitoring of atmospheric pressure and cosmic ray flux as measured in a Geiger counter. The investigation was intended as a pilot study in view of ongoing involvements of high-school teams operating…

  1. Ab initio/DFT/GIAO-CCSD(T) calculational study of the t-butyl cation: comparison of experimental data with structures, energetics, IR vibrational frequencies, and 13C NMR chemical shifts indicating preferred C(s) conformation.

    PubMed

    Rasul, Golam; Chen, Jonathan L; Prakash, G K Surya; Olah, George A

    2009-06-18

    The C(s) conformation of the tert-butyl cation 3 was established to be the preferred global energy minimum using a combination of ab initio, DFT, and CCSD(T) methodology with correlation-consistent basis sets. The potential energy surface of methyl rotation involving the C(3v), C(s), and C(3h) forms, however, in accord with previous studies, is quite flat. The computed IR absorptions of 3 indicate that it has the greatest degree of electron donation from C-H bonds into the C(+)-C bonds. The experimental (13)C NMR chemical shifts also agree very well with the experimental data.

  2. The roles of ingroup identification and outgroup entitativity in intergroup retribution.

    PubMed

    Stenstrom, Douglas M; Lickel, Brian; Denson, Thomas F; Miller, Norman

    2008-11-01

    A new aspect of intergroup conflict was investigated- vicarious retribution-in which neither the agent of retribution nor the target of retribution are directly involved in the initial intergroup provocation. The underlying processes involved in vicarious intergroup retribution were tested correlationally (Study 1) and experimentally (Study 2). Both ingroup identification and outgroup entitativity predict the degree of vicarious retribution. In both studies, there was evidence of motivated cognition, specifically that highly identified individuals perceived the outgroup as higher in entitativity than individuals low in identification. Structural equation modeling demonstrated that part of the effect of identification on retribution against the outgroup was mediated through perceptions of entitativity.

  3. Does the patient-held record improve continuity and related outcomes in cancer care: a systematic review.

    PubMed

    Gysels, Marjolein; Richardson, Alison; Higginson, Irene J

    2007-03-01

    To assess the effectiveness of the patient-held record (PHR) in cancer care. Patients with cancer may receive care from different services resulting in gaps. A PHR could provide continuity and patient involvement in care. Relevant literature was identified through five electronic databases (Medline, Embase, Cinahl, CCTR and CDSR) and hand searches. Patient-held records in cancer care with the purpose of improving communication and information exchange between and within different levels of care and to promote continuity of care and patients' involvement in their own care. Data extraction recorded characteristics of intervention, type of study and factors that contributed to methodological quality of individual studies. Data were then contrasted by setting, objectives, population, study design, outcome measures and changes in outcome, including knowledge, satisfaction, anxiety and depression. Methodological quality of randomized control trials and non-experimental studies were assessed with separate standard grading scales. Seven randomized control trials and six non-experimental studies were identified. Evaluations of the PHR have reached equivocal findings. Randomized trials found an absence of effect, non-experimental evaluations shed light on the conditions for its successful use. Most patients welcomed introduction of a PHR. Main problems related to its suitability for different patient groups and the lack of agreement between patients and health professionals regarding its function. Further research is required to determine the conditions under which the PHR can realize its potential as a tool to promote continuity of care and patient participation.

  4. Living organ donation: the effect of message frame on an altruistic behaviour.

    PubMed

    McGregor, Lesley M; Ferguson, Eamonn; O'Carroll, Ronan E

    2012-09-01

    This experimental study investigates the impact of message frame and risk perceptions upon willingness to consider living organ donation. A 2 (gain vs. loss) by 2 (liver vs. kidney) by 2 (involved vs. not involved) between-group study was conducted. Eighty-seven participants completed a questionnaire after reading a vignette designed to invite participants to consider living kidney or liver donation. Within a gain frame scenario, willingness to donate was significantly higher when the risk of donating was lower. The results have important implications for the generalizability of framing theories and the promotion of living organ donation.

  5. Fibulin-1 regulates the pathogenesis of tissue remodeling in respiratory diseases.

    PubMed

    Liu, Gang; Cooley, Marion A; Jarnicki, Andrew G; Hsu, Alan C-Y; Nair, Prema M; Haw, Tatt Jhong; Fricker, Michael; Gellatly, Shaan L; Kim, Richard Y; Inman, Mark D; Tjin, Gavin; Wark, Peter A B; Walker, Marjorie M; Horvat, Jay C; Oliver, Brian G; Argraves, W Scott; Knight, Darryl A; Burgess, Janette K; Hansbro, Philip M

    2016-06-16

    Airway and/or lung remodeling, involving exaggerated extracellular matrix (ECM) protein deposition, is a critical feature common to pulmonary diseases including chronic obstructive pulmonary disease (COPD), asthma, and idiopathic pulmonary fibrosis (IPF). Fibulin-1 (Fbln1), an important ECM protein involved in matrix organization, may be involved in the pathogenesis of these diseases. We found that Fbln1 was increased in COPD patients and in cigarette smoke-induced (CS-induced) experimental COPD in mice. Genetic or therapeutic inhibition of Fbln1c protected against CS-induced airway fibrosis and emphysema-like alveolar enlargement. In experimental COPD, this occurred through disrupted collagen organization and interactions with fibronectin, periostin, and tenascin-c. Genetic inhibition of Fbln1c also reduced levels of pulmonary inflammatory cells and proinflammatory cytokines/chemokines (TNF-α, IL-33, and CXCL1) in experimental COPD. Fbln1c -/- mice also had reduced airway remodeling in experimental chronic asthma and pulmonary fibrosis. Our data show that Fbln1c may be a therapeutic target in chronic respiratory diseases.

  6. Place and Pedagogy

    ERIC Educational Resources Information Center

    Orr, David

    2013-01-01

    David Orr's classic article links education to living in the outdoors and studying all disciplines through the unifying lens of place. Pedagogy of place counters abstraction, it is the natural world embodying principles of learning that involve direct observation, investigation, experimentation, and manual skills. Place is the laboratory providing…

  7. Scaffolding for Argumentation in Hypothetical and Theoretical Biology Concepts

    ERIC Educational Resources Information Center

    Weng, Wan-Yun; Lin, Yu-Ren; She, Hsiao-Ching

    2017-01-01

    The present study investigated the effects of online argumentation scaffolding on students' argumentation involving hypothetical and theoretical biological concepts. Two types of scaffolding were developed in order to improve student argumentation: continuous scaffolding and withdraw scaffolding. A quasi-experimental design was used with four…

  8. Social Identity and Achievement Gaps: Evidence from an Affirmation Intervention

    ERIC Educational Resources Information Center

    Dee, Thomas S.

    2015-01-01

    One provocative explanation for the continued persistence of minority achievement gaps involves the performance-dampening anxiety thought to be experienced by minority students in highly evaluative settings (i.e., "stereotype threat"). Recent field-experimental studies suggest that modest, low-cost "buffering" interventions…

  9. Who's Afraid of Something New?

    ERIC Educational Resources Information Center

    Learning Today, 1973

    1973-01-01

    Metro High, St. Louis, is described in pictures and words. The school, started in 1972, is a small, experimental school, which encourages self instruction, community involvement, and the use of real situations as learning experiences. The Zoology class, for instance, visits the zoo to study the animals. (SM)

  10. Introduction to Psychology.

    ERIC Educational Resources Information Center

    Edwards, Lesley

    Designed for community students interested in learning about psychology as a field of study, this module offers group and individual activities to involve the beginning student in research, experimentation and discussion. Unit 1, "What Is Psychology?," includes the use of animals in psychology, ethics, the history of psychology, an…

  11. Molecular Mechanisms in the shock induced decomposition of FOX-7

    NASA Astrophysics Data System (ADS)

    Mishra, Ankit; Tiwari, Subodh C.; Nakano, Aiichiro; Vashishta, Priya; Kalia, Rajiv; CACS Team

    Experimental and first principle computational studies on FOX 7 have either involved a very small system consisting of a few atoms or they did not take into account the decomposition mechanisms under extreme conditions of temperature and pressure. We have performed a large-scale reactive MD simulation using ReaxFF-lg force field to study the shock decomposition of FOX 7. The chemical composition of the principal decomposition products correlates well with experimental observations. Furthermore, we observed that the production of N2 and H2O was inter molecular in nature and was through different chemical pathways. Moreover, the production of CO and CO2 was delayed due to production of large stable C,O atoms cluster. These critical insights into the initial processes involved in the shock induced decomposition of FOX-7 will greatly help in understanding the factors playing an important role in the insensitiveness of this high energy material. This research is supported by AFOSR Award No. FA9550-16-1-0042.

  12. Protein kinase C is involved with upstream signaling of methyl farnesoate for photoperiod-dependent sex determination in the water flea Daphnia pulex

    PubMed Central

    Toyota, Kenji; Sato, Tomomi; Tatarazako, Norihisa

    2017-01-01

    ABSTRACT Sex determination of Daphnia pulex is decided by environmental conditions. We established a suitable experimental system for this study using D. pulex WTN6 strain, in which the sex of the offspring can be controlled by photoperiod. Long-day conditions induced females and short-day conditions induced males. Using this system, we previously found that methy farnesoate (MF), which is a putative innate juvenile hormone molecule in daphnids, is necessary for male sex determination and that protein kinase C (PKC) is a candidate factor of male sex determiner. In this study, we demonstrated that a PKC inhibitor [bisindolylmaleimide IV (BIM)] application strongly suppressed male offspring induction in the short-day condition. Moreover, co-treatment of BIM with MF revealed that PKC signaling acts upstream of MF signaling for male sex determination. This is the first experimental evidence that PKC is involved in the male sex determination process associated with methyl farnesoate signaling in daphnid species. PMID:27965197

  13. Experimental Study of Grit Particle Enhancement in Non-Shock Ignition

    NASA Astrophysics Data System (ADS)

    Browning, Richard V.; Peterson, Paul D.; Roemer, Edward L.; Oldenborg, Michael R.; Thompson, Darla G.; Deluca, Racci

    2006-07-01

    The drop weight impact test is the most commonly used configuration for evaluating sensitivity of explosives to non-shock ignition. Although developed 60 years ago and widely used both as a material compression test and as a test bed for understanding the ignition process itself, little is known about the flow mechanisms or involvement of grit particles as sensitizing agents. In this paper, we present the results of a series of experiments designed to study the flow mechanisms and events leading up to ignition. The experimental configuration used involves two pellet sizes, 3 and 5 mm in diameter, tested with three conditions: (1) smooth steel anvils, (2) standard flint sandpaper, and (3) shed grit particles loaded between the steel anvils and the pellet faces. Diagnostics include optical micrographs, and scanning electron micrographs. Un-reacted samples show a variety of morphologies, including what appear to be quenched reaction sites, even at very low drop heights. Quasi-static crushing experiments were also done to quantify load-time histories.

  14. Experimental Study of Grit Particle Enhancement in Non-Shock Ignition of PBX 9501

    NASA Astrophysics Data System (ADS)

    Peterson, Paul

    2005-07-01

    The drop weight impact test is the most commonly used configuration for evaluating sensitivity of explosives to non-shock ignition. Although developed 60 years ago and widely used both as a material compression test and as a test bed for understanding the ignition process itself, little is known about the flow mechanisms or involvement of grit particles as sensitizing agents. In this paper we present the results of a series of experiments designed to study the flow mechanisms and events leading up to ignition. The experimental configuration used involves two pellet sizes, 3 and 5 mm in diameter, tested in three conditions, (1) with smooth steel anvils, (2) with standard flint sandpaper, and (3) with shed grit particles loaded between the steel anvils and the pellet faces. Diagnostics include optical micrographs, and scanning electron micrographs. Un-reacted samples show a variety of morphologies, including what appear to be quenched reaction sites, even at very low drop heights. Quasi-static crushing experiments were also done to quantify load-time histories.

  15. Differences in Risk Aversion between Young and Older Adults.

    PubMed

    Albert, Steven M; Duffy, John

    2012-01-15

    Research on decision-making strategies among younger and older adults suggests that older adults may be more risk averse than younger people in the case of potential losses. These results mostly come from experimental studies involving gambling paradigms. Since these paradigms involve substantial demands on memory and learning, differences in risk aversion or other features of decision-making attributed to age may in fact reflect age-related declines in cognitive abilities. In the current study, older and younger adults completed a simpler, paired lottery choice task used in the experimental economics literature to elicit risk aversion. A similar approach was used to elicit participants' discount rates. The older adult group was more risk averse than younger adults (p < .05) and also had a higher discount rate (15.6-21.0% vs. 10.3-15.5%, p < .01), indicating lower expected utility from future income. Risk aversion and implied discount rates were weakly correlated. It may be valuable to investigate developmental changes in neural correlates of decision-making across the lifespan.

  16. Differences in Risk Aversion between Young and Older Adults

    PubMed Central

    Albert, Steven M.; Duffy, John

    2013-01-01

    Research on decision-making strategies among younger and older adults suggests that older adults may be more risk averse than younger people in the case of potential losses. These results mostly come from experimental studies involving gambling paradigms. Since these paradigms involve substantial demands on memory and learning, differences in risk aversion or other features of decision-making attributed to age may in fact reflect age-related declines in cognitive abilities. In the current study, older and younger adults completed a simpler, paired lottery choice task used in the experimental economics literature to elicit risk aversion. A similar approach was used to elicit participants' discount rates. The older adult group was more risk averse than younger adults (p < .05) and also had a higher discount rate (15.6-21.0% vs. 10.3-15.5%, p < .01), indicating lower expected utility from future income. Risk aversion and implied discount rates were weakly correlated. It may be valuable to investigate developmental changes in neural correlates of decision-making across the lifespan. PMID:24319671

  17. Passing the Baton: An Experimental Study of Shift Handover

    NASA Technical Reports Server (NTRS)

    Parke, Bonny; Hobbs, Alan; Kanki, Barbara

    2010-01-01

    Shift handovers occur in many safety-critical environments, including aviation maintenance, medicine, air traffic control, and mission control for space shuttle and space station operations. Shift handovers are associated with increased risk of communication failures and human error. In dynamic industries, errors and accidents occur disproportionately after shift handover. Typical shift handovers involve transferring information from an outgoing shift to an incoming shift via written logs, or in some cases, face-to-face briefings. The current study explores the possibility of improving written communication with the support modalities of audio and video recordings, as well as face-to-face briefings. Fifty participants participated in an experimental task which mimicked some of the critical challenges involved in transferring information between shifts in industrial settings. All three support modalities, face-to-face, video, and audio recordings, reduced task errors significantly over written communication alone. The support modality most preferred by participants was face-to-face communication; the least preferred was written communication alone.

  18. Experimental models to study cholangiocyte biology

    PubMed Central

    Tietz, Pamela S.; Chen, Xian-Ming; Gong, Ai-Yu; Huebert, Robert C.; Masyuk, Anatoliy; Masyuk, Tatyana; Splinter, Patrick L.; LaRusso, Nicholas F.

    2002-01-01

    Cholangiocytes-the epithelial cells which line the bile ducts-are increasingly recognized as important transporting epithelia actively involved in the absorption and secretion of water, ions, and solutes. This recognition is due in part to the recent development of new experimental models. New biologic concepts have emerged including the identification and topography of receptors and flux proteins on the apical and/or basolateral membrane which are involved in the molecular mechanisms of ductal bile secretion. Individually isolated and/or perfused bile duct units from livers of rats and mice serve as new, physiologically relevant in vitro models to study cholangiocyte transport. Biliary tree dimensions and novel insights into anatomic remodeling of proliferating bile ducts have emerged from three-dimensional reconstruction using CT scanning and sophisticated software. Moreover, new pathologic concepts have arisen regarding the interaction of cholangiocytes with pathogens such as Cryptosporidium parvum. These concepts and associated methodologies may provide the framework to develop new therapies for the cholangiopathies, a group of important hepatobiliary diseases in which cholangiocytes are the target cell. PMID:11833061

  19. Convection, buoyancy or endolymph expansion: what is the actual mechanism responsible for the caloric response of semicircular canals?

    PubMed

    Valli, Paulo; Buizza, Angelo; Botta, Laura; Zucca, Giampiero; Ghezzi, Luciano; Valli, Stefano

    The mechanisms underlying caloric nystagmus are still matter of debate. The original theory proposed by Barany and more recently by Pau and Limberg suggested that convective endolymphatic currents were involved. In contrast Gentine et al. suggested that the main mechanism responsible for caloric nystagmus is buoyancy due to calorization of the endolymph, without the need of continuous convective currents. Finally, other authors (Scherer and Clarke, Arai et al.) proposed that thermal expansion or contraction of the endolymph were involved. In the present study experimental conditions have been considered able to discriminate between these different models. The experiments, were carried out on isolated labyrinth preparations of the frog. Only the predictions of the model based on buoyancy were fully consistent with the experimental results whereas those provided by the other models were not.

  20. In silico simulations of experimental protocols for cardiac modeling.

    PubMed

    Carro, Jesus; Rodriguez, Jose Felix; Pueyo, Esther

    2014-01-01

    A mathematical model of the AP involves the sum of different transmembrane ionic currents and the balance of intracellular ionic concentrations. To each ionic current corresponds an equation involving several effects. There are a number of model parameters that must be identified using specific experimental protocols in which the effects are considered as independent. However, when the model complexity grows, the interaction between effects becomes increasingly important. Therefore, model parameters identified considering the different effects as independent might be misleading. In this work, a novel methodology consisting in performing in silico simulations of the experimental protocol and then comparing experimental and simulated outcomes is proposed for parameter model identification and validation. The potential of the methodology is demonstrated by validating voltage-dependent L-type calcium current (ICaL) inactivation in recently proposed human ventricular AP models with different formulations. Our results show large differences between ICaL inactivation as calculated from the model equation and ICaL inactivation from the in silico simulations due to the interaction between effects and/or to the experimental protocol. Our results suggest that, when proposing any new model formulation, consistency between such formulation and the corresponding experimental data that is aimed at being reproduced needs to be first verified considering all involved factors.

  1. 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 flunarizine as add-on therapy in refractory epilepsy.

  2. A caregiver educational program improves quality of life and burden for cancer patients and their caregivers: a randomised clinical trial.

    PubMed

    Belgacem, Bénédicte; Auclair, Candy; Fedor, Marie-Christine; Brugnon, David; Blanquet, Marie; Tournilhac, Olivier; Gerbaud, Laurent

    2013-12-01

    The French setting, including laws and guidelines, advocates greater involvement of informal caregivers in the care of cancer patients to protect the caregivers from depression, distress, and a decrease in their quality of life. This study aimed to assess the efficacy of a caregiver educational programme by measuring two outcomes: patients' and caregivers' quality of life and caregivers' burden. A multicentre randomised controlled trial was performed in six oncology wards in French hospitals. Eligible patients had a cancer, a main caregiver, allowed their caregivers' involvement, and received an inclusion agreement by a doctor/psychologist dyad. The experimental group participated in an educational programme performed by nurses to improve their skills in meal support, nursing care, welfare care, or symptom management. The SF36 and the Zarit burden scales were used to measure quality of life and caregivers' burden at the beginning and at the end of the study. 67 patients were randomised and 33 were included in the experimental group. Evolution scores, which measured the difference between baseline and final scores, showed an improvement in patients' and caregivers' quality of life and an alleviated burden for experimental group caregivers. An educational programme for caregivers encourages the involvement of patients, informal caregivers and health-care providers in a triangular relationship which enhances the quality of life of patients and caregivers alike and decreases caregivers' burden. Care organisation should therefore be rethought as a triangular relationship between patients, caregivers and health-care providers, with nurses as the mainstay. Copyright © 2013 Elsevier Ltd. All rights reserved.

  3. Risk-taking behaviors and prefrontal cortex activity of male adolescents in the presence of peer passengers during simulated driving : a functional near-infrared spectroscopy (fNIRS) study.

    DOT National Transportation Integrated Search

    2015-09-01

    Crash statistics show that adolescent drivers are more likely to be involved in motor-vehicle crashes than adults and that the : presence of peer passengers pose an additional risk factor for crashes. Experimental and observational studies show that ...

  4. A Healthier Workplace? Implementation of Fruit Boxes in the Workplace

    ERIC Educational Resources Information Center

    Pescud, Melanie; Waterworth, Pippa; Shilton, Trevor; Teal, Renee; Slevin, Terry; Ledger, Melissa; Lester, Leanne; Rosenberg, Michael

    2016-01-01

    Objective: The purpose of this study was to investigate whether making fruit boxes available in the workplace is a successful health promotion strategy. Design: A quasi-experimental study involving three conditions--free fruit, 50c per piece of fruit and $1 per piece of fruit--to investigate the effect of a contribution scheme on employees' fruit…

  5. E-Readers and the Effects on Students' Reading Motivation, Attitude, and Comprehension

    ERIC Educational Resources Information Center

    Long, Deanna

    2014-01-01

    The purpose of this study was to determine if the use of E-readers during guided reading instruction would affect students' reading motivation, attitude toward reading, and reading comprehension. The study utilized on a quasi-experimental mixed methods research design that involved 35 fifth grade students in two fifth grade reading classes. For 10…

  6. Improving Students' Conceptual Understanding of a Specific Content Learning: A Designed Teaching Sequence

    ERIC Educational Resources Information Center

    Ahmad, N. J.; Lah, Y. Che

    2012-01-01

    The efficacy of a teaching sequence designed for a specific content of learning of electrochemistry is described in this paper. The design of the teaching draws upon theoretical insights into perspectives on learning and empirical studies to improve the teaching of this topic. A case study involving two classes, the experimental and baseline…

  7. Radiographic applications of spatial frequency multiplexing

    NASA Technical Reports Server (NTRS)

    Macovski, A.

    1981-01-01

    The application of spacial frequency encoding techniques which allow different regions of the X-ray spectrum to be encoded on conventional radiographs was studied. Clinical considerations were reviewed, as were experimental studies involving the encoding and decoding of X-ray images at different energies and the subsequent processing of the data to produce images of specific materials in the body.

  8. The Relation between Individual Interest and Knowledge Acquisition

    ERIC Educational Resources Information Center

    Rotgans, Jerome I.; Schmidt, Henk G.

    2017-01-01

    The objective of this study was to examine how individual interest and knowledge acquisition are causally related. Three hypotheses were tested using a cross-lagged panel analysis (N = 186) and two quasi-experimental studies (N = 68 and N = 108) involving students from schools in Singapore. The first hypothesis is the broadly shared standard…

  9. Studying technology use as social practice: the untapped potential of ethnography

    PubMed Central

    2011-01-01

    Information and communications technologies (ICTs) in healthcare are often introduced with expectations of higher-quality, more efficient, and safer care. Many fail to meet these expectations. We argue here that the well-documented failures of ICTs in healthcare are partly attributable to the philosophical foundations of much health informatics research. Positivistic assumptions underpinning the design, implementation and evaluation of ICTs (in particular the notion that technology X has an impact which can be measured and reproduced in new settings), and the deterministic experimental and quasi-experimental study designs which follow from these assumptions, have inherent limitations when ICTs are part of complex social practices involving multiple human actors. We suggest that while experimental and quasi-experimental studies have an important place in health informatics research overall, ethnography is the preferred methodological approach for studying ICTs introduced into complex social systems. But for ethnographic approaches to be accepted and used to their full potential, many in the health informatics community will need to revisit their philosophical assumptions about what counts as research rigor. PMID:21521535

  10. Mitochondria, oligodendrocytes and inflammation in bipolar disorder: evidence from transcriptome studies points to intriguing parallels with multiple sclerosis

    PubMed Central

    Konradi, Christine; Sillivan, Stephanie E.; Clay, Hayley B.

    2011-01-01

    Gene expression studies of bipolar disorder (BPD) have shown changes in transcriptome profiles in multiple brain regions. Here we summarize the most consistent findings in the scientific literature, and compare them to data from schizophrenia (SZ) and major depressive disorder (MDD). The transcriptome profiles of all three disorders overlap, making the existence of a BPD-specific profile unlikely. Three groups of functionally related genes are consistently expressed at altered levels in BPD, SZ and MDD. Genes involved in energy metabolism and mitochondrial function are downregulated, genes involved in immune response and inflammation are upregulated, and genes expressed in oligodendrocytes are downregulated. Experimental paradigms for multiple sclerosis demonstrate a tight link between energy metabolism, inflammation and demyelination. These studies also show variabilities in the extent of oligodendrocyte stress, which can vary from a downregulation of oligodendrocyte genes, such as observed in psychiatric disorders, to cell death and brain lesions seen in multiple sclerosis. We conclude that experimental models of multiple sclerosis could be of interest for the research of BPD, SZ and MDD. PMID:21310238

  11. The Johnson Space Center Experimental Impact Lab: Contributions Toward Understanding the Evolution of the Solar System

    NASA Technical Reports Server (NTRS)

    See, T. H.; Montes, R.

    2012-01-01

    Impact is the most common and only weathering phenomenon affecting all the planetary bodies (e.g., planets, satellites, asteroids, comets, etc.) in the solar system. NASA Johnson Space Center s Experimental Impact Laboratory (EIL) includes three accelerators that are used in support of research into the effects of impact on the formation and evolution of the solar system. They permit researchers to study a wide variety of phenomena associated with high-velocity impacts into a wide range of geologic targets and materials relevant to astrobiological studies. By studying these processes, researchers can investigate the histories and evolution of planetary bodies and the solar system as a whole. While the majority of research conducted in the EIL addresses questions involving planetary impacts, work involving spacecraft components has been performed on occasion. An example of this is the aerogel collector material flown on the Stardust spacecraft that traveled to Comet Wild-2. This capture medium was tested and flight qualified using the 5 mm Light-Gas Gun located in the EIL.

  12. The Experimental Cloud Lidar Pilot Study (ECLIPS) for cloud-radiation research

    NASA Technical Reports Server (NTRS)

    Platt, C. M.; Young, S. A.; Carswell, A. I.; Pal, S. R.; Mccormick, M. P.; Winker, D. M.; Delguasta, M.; Stefanutti, L.; Eberhard, W. L.; Hardesty, M.

    1994-01-01

    The Experimental Cloud Lidar Pilot Study (ECLIPS) was initiated to obtain statistics on cloud-base height, extinction, optical depth, cloud brokenness, and surface fluxes. Two observational phases have taken place, in October-December 1989 and April-July 1991, with intensive 30-day periods being selected within the two time intervals. Data are being archived at NASA Langley Research Center and, once there, are readily available to the international scientific community. This article describes the scale of the study in terms of its international involvement and in the range of data being recorded. Lidar observations of cloud height and backscatter coefficient have been taken from a number of ground-based stations spread around the globe. Solar shortwave and infrared longwave fluxes and infrared beam radiance have been measured at the surface wherever possible. The observations have been tailored to occur around the overpass times of the NOAA weather satellites. This article describes in some detail the various retrieval methods used to obtain results on cloud-base height, extinction coefficient, and infrared emittance, paying particular attention to the uncertainties involved.

  13. Estimating the effect of gang membership on nonviolent and violent delinquency: a counterfactual analysis.

    PubMed

    Barnes, J C; Beaver, Kevin M; Miller, J Mitchell

    2010-01-01

    This study reconsiders the well-known link between gang membership and criminal involvement. Recently developed analytical techniques enabled the approximation of an experimental design to determine whether gang members, after being matched with similarly situated nongang members, exhibited greater involvement in nonviolent and violent delinquency. Findings indicated that while gang membership is a function of self-selection, selection effects alone do not account for the greater involvement in delinquency exhibited by gang members. After propensity score matching was employed, gang members maintained a greater involvement in both nonviolent and violent delinquency when measured cross-sectionally, but only violent delinquency when measured longitudinally. Additional analyses using inverse probability of treatment weights reaffirmed these conclusions. © 2010 Wiley-Liss, Inc.

  14. Predicting network modules of cell cycle regulators using relative protein abundance statistics.

    PubMed

    Oguz, Cihan; Watson, Layne T; Baumann, William T; Tyson, John J

    2017-02-28

    Parameter estimation in systems biology is typically done by enforcing experimental observations through an objective function as the parameter space of a model is explored by numerical simulations. Past studies have shown that one usually finds a set of "feasible" parameter vectors that fit the available experimental data equally well, and that these alternative vectors can make different predictions under novel experimental conditions. In this study, we characterize the feasible region of a complex model of the budding yeast cell cycle under a large set of discrete experimental constraints in order to test whether the statistical features of relative protein abundance predictions are influenced by the topology of the cell cycle regulatory network. Using differential evolution, we generate an ensemble of feasible parameter vectors that reproduce the phenotypes (viable or inviable) of wild-type yeast cells and 110 mutant strains. We use this ensemble to predict the phenotypes of 129 mutant strains for which experimental data is not available. We identify 86 novel mutants that are predicted to be viable and then rank the cell cycle proteins in terms of their contributions to cumulative variability of relative protein abundance predictions. Proteins involved in "regulation of cell size" and "regulation of G1/S transition" contribute most to predictive variability, whereas proteins involved in "positive regulation of transcription involved in exit from mitosis," "mitotic spindle assembly checkpoint" and "negative regulation of cyclin-dependent protein kinase by cyclin degradation" contribute the least. These results suggest that the statistics of these predictions may be generating patterns specific to individual network modules (START, S/G2/M, and EXIT). To test this hypothesis, we develop random forest models for predicting the network modules of cell cycle regulators using relative abundance statistics as model inputs. Predictive performance is assessed by the areas under receiver operating characteristics curves (AUC). Our models generate an AUC range of 0.83-0.87 as opposed to randomized models with AUC values around 0.50. By using differential evolution and random forest modeling, we show that the model prediction statistics generate distinct network module-specific patterns within the cell cycle network.

  15. Fundamental phenomena on fuel decomposition and boundary layer combustion processes with applications to hybrid rocket motors

    NASA Technical Reports Server (NTRS)

    Kuo, Kenneth K.; Lu, Y. C.; Chiaverini, Martin J.; Harting, George C.

    1994-01-01

    An experimental study on the fundamental processes involved in fuel decomposition and boundary layer combustion in hybrid rocket motors is being conducted at the High Pressure Combustion Laboratory of the Pennsylvania State University. This research should provide a useful engineering technology base in the development of hybrid rocket motors as well as a fundamental understanding of the complex processes involved in hybrid propulsion. A high pressure slab motor has been designed and manufactured for conducting experimental investigations. Oxidizer (LOX or GOX) supply and control systems have been designed and partly constructed for the head-end injection into the test chamber. Experiments using HTPB fuel, as well as fuels supplied by NASA designated industrial companies will be conducted. Design and construction of fuel casting molds and sample holders have been completed. The portion of these items for industrial company fuel casting will be sent to the McDonnell Douglas Aerospace Corporation in the near future. The study focuses on the following areas: observation of solid fuel burning processes with LOX or GOX, measurement and correlation of solid fuel regression rate with operating conditions, measurement of flame temperature and radical species concentrations, determination of the solid fuel subsurface temperature profile, and utilization of experimental data for validation of a companion theoretical study (Part 2) also being conducted at PSU.

  16. Challenging Density Functional Theory Calculations with Hemes and Porphyrins.

    PubMed

    de Visser, Sam P; Stillman, Martin J

    2016-04-07

    In this paper we review recent advances in computational chemistry and specifically focus on the chemical description of heme proteins and synthetic porphyrins that act as both mimics of natural processes and technological uses. These are challenging biochemical systems involved in electron transfer as well as biocatalysis processes. In recent years computational tools have improved considerably and now can reproduce experimental spectroscopic and reactivity studies within a reasonable error margin (several kcal·mol(-1)). This paper gives recent examples from our groups, where we investigated heme and synthetic metal-porphyrin systems. The four case studies highlight how computational modelling can correctly reproduce experimental product distributions, predicted reactivity trends and guide interpretation of electronic structures of complex systems. The case studies focus on the calculations of a variety of spectroscopic features of porphyrins and show how computational modelling gives important insight that explains the experimental spectra and can lead to the design of porphyrins with tuned properties.

  17. Laboratory grown subaerial biofilms on granite: application to the study of bioreceptivity.

    PubMed

    Vázquez-Nion, Daniel; Silva, Benita; Troiano, Federica; Prieto, Beatriz

    2017-01-01

    Simulated environmental colonisation of granite was induced under laboratory conditions in order to develop an experimental protocol for studying bioreceptivity. The experimental set-up proved suitable for producing subaerial biofilms by inoculating granite blocks with planktonic multi-species phototrophic cultures derived from natural biofilms. The ability of four different cultures to form biofilms was monitored over a three-month growth period via colour measurements, quantification of photosynthetic pigments and EPS, and CLSM observations. One of the cultures under study, which comprised several taxa including Bryophyta, Charophyta, Chlorophyta and Cyanobacteria, was particularly suitable as an inoculum, mainly because of its microbial richness, its rapid adaptability to the substratum and its high colonisation capacity. The use of this culture as an inoculum in the proposed experimental set-up to produce subaerial biofilms under laboratory conditions will contribute to standardising the protocols involved, thus enabling more objective assessment of the bioreceptivity of granite in further experiments.

  18. Thermal conductivity improvement in carbon nanoparticle doped PAO oil: An experimental study

    NASA Astrophysics Data System (ADS)

    Shaikh, S.; Lafdi, K.; Ponnappan, R.

    2007-03-01

    The present work involves a study on the thermal conductivity of nanoparticle-oil suspensions for three types of nanoparticles, namely, carbon nanotubes (CNTs), exfoliated graphite (EXG), and heat treated nanofibers (HTT) with PAO oil as the base fluid. To accomplish the above task, an experimental analysis is performed using a modern light flash technique (LFA 447) for measuring the thermal conductivity of the three types of nanofluids, for different loading of nanoparticles. The experimental results show a similar trend as observed in literature for nanofluids with a maximum enhancement of approximately 161% obtained for the CNT-PAO oil suspension. The overall percent enhancements for different volume fractions of the nanoparticles are highest for the CNT-based nanofluid, followed by the EXG and the HTT. The findings from this study for the three different types of carbon nanoparticles can have great potential in the field of thermal management.

  19. A Simple Experiment to Explore Standing Waves in a Flexible Corrugated Sound Tube

    NASA Astrophysics Data System (ADS)

    Amorim, Maria Eva; Sousa, Teresa Delmira; Carvalho, P. Simeão; Sousa, Adriano Sampaioe

    2011-09-01

    Sound tubes, pipes, and singing rods are used as musical instruments and as toys to perform amusing experiments. In particular, corrugated tubes present unique characteristics with respect to the sounds they can produce; that is why they have been studied so intensively, both at theoretical and experimental levels.1-4 Experimental studies usually involve expensive and sophisticated equipment that is out of reach of school laboratory facilities.3-6 In this paper we show how to investigate quantitatively the sounds produced by a flexible sound tube corrugated on the inside by using educational equipment readily available in school laboratories, such as the oscilloscope, the microphone, the anemometer, and the air pump. We show that it is possible for students to study the discontinuous spectrum of sounds produced by a flexible corrugated tube and go even further, computing the speed of sound in air with a simple experimental procedure.

  20. 47 CFR 5.63 - Supplementary statements required.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... experimental authorization involving a satellite system must submit a description of the design and operational... 5.63 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL EXPERIMENTAL RADIO SERVICE (OTHER... for an authorization in the Experimental Radio Service must enclose with the application a narrative...

  1. 47 CFR 5.63 - Supplementary statements required.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... experimental authorization involving a satellite system must submit a description of the design and operational... 5.63 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL EXPERIMENTAL RADIO SERVICE (OTHER... for an authorization in the Experimental Radio Service must enclose with the application a narrative...

  2. Ego involvement increases doping likelihood.

    PubMed

    Ring, Christopher; Kavussanu, Maria

    2018-08-01

    Achievement goal theory provides a framework to help understand how individuals behave in achievement contexts, such as sport. Evidence concerning the role of motivation in the decision to use banned performance enhancing substances (i.e., doping) is equivocal on this issue. The extant literature shows that dispositional goal orientation has been weakly and inconsistently associated with doping intention and use. It is possible that goal involvement, which describes the situational motivational state, is a stronger determinant of doping intention. Accordingly, the current study used an experimental design to examine the effects of goal involvement, manipulated using direct instructions and reflective writing, on doping likelihood in hypothetical situations in college athletes. The ego-involving goal increased doping likelihood compared to no goal and a task-involving goal. The present findings provide the first evidence that ego involvement can sway the decision to use doping to improve athletic performance.

  3. An Experimental Test of the Roles of Audience Involvement and Message Frame in Shaping Public Reactions to Celebrity Illness Disclosures.

    PubMed

    Myrick, Jessica Gall

    2018-04-13

    Much research has investigated what happens when celebrities disclose an illness (via media) to the public. While audience involvement (i.e., identification and parasocial relationships) is often the proposed mechanism linking illness disclosures with audience behavior change, survey designs have prevented researchers from understanding if audience involvement prior to the illness disclosure actually predicts post-disclosure emotions, cognitions, and behaviors. Rooted in previous work on audience involvement as well as the Extended Parallel Process Model, the present study uses a national online experiment (N = 1,068) to test how pre-disclosure audience involvement may initiate post-disclosure effects for the message context of skin cancer. The data demonstrate that pre-disclosure audience involvement as well as the celebrity's framing of the disclosure can shape emotional responses (i.e., fear and hope), and that cognitive perceptions of the illness itself also influence behavioral intentions.

  4. Experimental Study on the Precise Orbit Determination of the BeiDou Navigation Satellite System

    PubMed Central

    He, Lina; Ge, Maorong; Wang, Jiexian; Wickert, Jens; Schuh, Harald

    2013-01-01

    The regional service of the Chinese BeiDou satellite navigation system is now in operation with a constellation including five Geostationary Earth Orbit satellites (GEO), five Inclined Geosynchronous Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Besides the standard positioning service with positioning accuracy of about 10 m, both precise relative positioning and precise point positioning are already demonstrated. As is well known, precise orbit and clock determination is essential in enhancing precise positioning services. To improve the satellite orbits of the BeiDou regional system, we concentrate on the impact of the tracking geometry and the involvement of MEOs, and on the effect of integer ambiguity resolution as well. About seven weeks of data collected at the BeiDou Experimental Test Service (BETS) network is employed in this experimental study. Several tracking scenarios are defined, various processing schemata are designed and carried out; and then, the estimates are compared and analyzed in detail. The results show that GEO orbits, especially the along-track component, can be significantly improved by extending the tracking network in China along longitude direction, whereas IGSOs gain more improvement if the tracking network extends in latitude. The involvement of MEOs and ambiguity-fixing also make the orbits better. PMID:23529116

  5. Experimental study on the precise orbit determination of the BeiDou navigation satellite system.

    PubMed

    He, Lina; Ge, Maorong; Wang, Jiexian; Wickert, Jens; Schuh, Harald

    2013-03-01

    The regional service of the Chinese BeiDou satellite navigation system is now in operation with a constellation including five Geostationary Earth Orbit satellites (GEO), five Inclined Geosynchronous Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Besides the standard positioning service with positioning accuracy of about 10 m, both precise relative positioning and precise point positioning are already demonstrated. As is well known, precise orbit and clock determination is essential in enhancing precise positioning services. To improve the satellite orbits of the BeiDou regional system, we concentrate on the impact of the tracking geometry and the involvement of MEOs, and on the effect of integer ambiguity resolution as well. About seven weeks of data collected at the BeiDou Experimental Test Service (BETS) network is employed in this experimental study. Several tracking scenarios are defined, various processing schemata are designed and carried out; and then, the estimates are compared and analyzed in detail. The results show that GEO orbits, especially the along-track component, can be significantly improved by extending the tracking network in China along longitude direction, whereas IGSOs gain more improvement if the tracking network extends in latitude. The involvement of MEOs and ambiguity-fixing also make the orbits better.

  6. Generators of the brainstem auditory evoked potential in cat. I. An experimental approach to their identification.

    PubMed

    Melcher, J R; Knudson, I M; Fullerton, B C; Guinan, J J; Norris, B E; Kiang, N Y

    1996-04-01

    This paper is the first in a series aimed at identifying the cellular generators of the brainstem auditory evoked potential (BAEP) in cats. The approach involves (1) developing experimental procedures for making small selective lesions and determining the corresponding changes in BAEP waveforms, (2) identifying brainstem regions involved in BAEP generation by examining the effects of lesions on the BAEP and (3) identifying specific cell populations involved by combining the lesion results with electrophysiological and anatomical information from other kinds of studies. We created lesions in the lower brainstem by injecting kainic acid which is generally toxic for neuronal cell bodies but not for axons and terminals. This first paper describes the justifications for using kainic acid, explains the associated problems, and develops a methodology that addresses the main difficulties. The issues and aspects of the specific methods are generally applicable to physiological and anatomical studies using any neurotoxin, as well as to the present BAEP study. The methods chosen involved (1) measuring the BAEP at regular intervals until it reached a post-injection steady state and perfusing the animals with fixative shortly after the last BAEP recordings were made, (2) using objective criteria to distinguish injection-related BAEP changes from unrelated ones, (3) making control injections to identify effects not due to kainic acid toxicity, (4) verifying the anatomical and functional integrity of axons in lesioned regions, and (5) examining injected brainstems microscopically for cell loss and cellular abnormalities indicating dysfunction. This combination of methods enabled us to identify BAEP changes which are clearly correlated with lesion locations.

  7. THE INVOLVEMENT OF HUMAN MONOGENIC CARDIOMYOPATHY GENES IN EXPERIMENTAL POLYGENIC CARDIAC HYPERTROPHY.

    PubMed

    Prestes, Priscilla R; Marques, Francine Z; Lopez-Campos, Guillermo; Lewandowski, Paul; Delbridge, Lea M D; Charchar, Fadi J; Harrap, Stephen B

    2018-05-18

    Hypertrophic cardiomyopathy thickens heart muscles reducing functionality and increasing risk of cardiac disease and morbidity. Genetic factors are involved, but their contribution is poorly understood. We used the hypertrophic heart rat (HHR), a unique normotensive polygenic model of cardiac hypertrophy and heart failure to investigate the role of genes associated with monogenic human cardiomyopathy. We selected 42 genes involved in monogenic human cardiomyopathies to study: 1) DNA variants, by sequencing the whole-genome of 13-week old HHR and age-matched normal heart rat (NHR), its genetic control strain; 2) mRNA expression, by targeted RNA-sequencing in left ventricles of HHR and NHR at five ages (2-days old, 4-, 13-, 33- and 50-weeks old) compared to human idiopathic dilated data; and 3) microRNA expression, with rat microRNA microarrays in left ventricles of 2-days old HHR and age-matched NHR. We also investigated experimentally validated microRNA-mRNA interactions. Whole-genome sequencing revealed unique variants mostly located in non-coding regions of HHR and NHR. We found 29 genes differentially expressed in at least one age. Genes encoding desmoglein 2 (Dsg2) and transthyretin (Ttr) were significantly differentially expressed at all ages in the HHR, but only Ttr was also differentially expressed in human idiopathic cardiomyopathy. Lastly, only two microRNAs differentially expressed in the HHR were present in our comparison of validated microRNA-mRNA interactions. These two microRNAs interact with five of the genes studied. Our study shows that genes involved in monogenic forms of human cardiomyopathies may also influence polygenic forms of the disease.

  8. Experimental and theoretical investigation on the molecular structure, spectroscopic and electric properties of 2,4-dinitrodiphenylamine, 2-nitro-4-(trifluoromethyl)aniline and 4-bromo-2-nitroaniline

    NASA Astrophysics Data System (ADS)

    Hernández-Paredes, Javier; Hernández-Negrete, Ofelia; Carrillo-Torres, Roberto C.; Sánchez-Zeferino, Raúl; Duarte-Moller, Alberto; Alvarez-Ramos, Mario E.

    2015-10-01

    2,4-Dinitrodiphenylamine (I), 2-nitro-4-(trifluoromethyl)aniline (II) and 4-bromo-2-nitroaniline (III) have been investigated by DFT and experimental FTIR, Raman and UV-Vis spectroscopies. The gas-phase molecular geometries were consistent with similar compounds already reported in the literature. From the vibrational analysis, the main functional groups were identified and their absorption bands were assigned. Some differences were found between the calculated and the experimental UV-Vis spectra. These differences were analyzed and explained in terms of the TD-DFT/B3LYP limitations, which were mainly attributed to charge-transfer (CT) effects. These findings were in agreement with previous works, which reported that TD-DFT/B3LYP calculations diverge from experimental results when the electronic transitions involve CT. Despite this, TD-DFT/B3LYP calculations provided satisfactory results and a detailed description of the electronic transitions involved in the absorption bands of the UV-Vis spectra. In terms of the NLO properties, it was found that compound (I) is a good candidate for NLO applications and deserves further study due to its good β values. However, the β values for compounds (II) and (III) were negatively affected compared to those found on o-nitroaniline.

  9. Principles and Techniques of Radiation Chemistry.

    ERIC Educational Resources Information Center

    Dorfman, Leon M.

    1981-01-01

    Discusses the physical processes involved in the deposition of energy from ionizing radiation in the absorber system. Identifies principles relevant to these processes which are responsible for ionization and excitation of the components of the absorber system. Briefly describes some experimental techniques in use in radiation chemical studies.…

  10. Experimental Lung Cancer Drug Shows Early Promise | Frederick National Laboratory for Cancer Research

    Cancer.gov

    A first-of-its-kind drug is showing early promise in attacking certain lung cancers that are hard to treat because they build up resistance to conventional chemotherapy. The drug, CO-1686, performed well in a preclinical study involving xenograft and

  11. 75 FR 53325 - Proposed Scientific Integrity Policy of the Department of the Interior

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-31

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

  12. Experimental Studies on Hypersonic Stagnation Point Chemical Environment

    DTIC Science & Technology

    2006-02-01

    conditions [60]. Having this complete definition we will focus on the chemical environment produce in the SPR. 3.2 Chemical environment evaluation Flow ... chemistry involves a very large number of processes and microscopic phenomena, they are usually summarized in a set of chemical reactions, with their own

  13. The Development of Animal Behavior: From Lorenz to Neural Nets

    NASA Astrophysics Data System (ADS)

    Bolhuis, Johan J.

    In the study of behavioral development both causal and functional approaches have been used, and they often overlap. The concept of ontogenetic adaptations suggests that each developmental phase involves unique adaptations to the environment of the developing animal. The functional concept of optimal outbreeding has led to further experimental evidence and theoretical models concerning the role of sexual imprinting in the evolutionary process of sexual selection. From a causal perspective it has been proposed that behavioral ontogeny involves the development of various kinds of perceptual, motor, and central mechanisms and the formation of connections among them. This framework has been tested for a number of complex behavior systems such as hunger and dustbathing. Imprinting is often seen as a model system for behavioral development in general. Recent advances in imprinting research have been the result of an interdisciplinary effort involving ethology, neuroscience, and experimental psychology, with a continual interplay between these approaches. The imprinting results are consistent with Lorenz' early intuitive suggestions and are also reflected in the architecture of recent neural net models.

  14. A brief understanding of process optimisation in microwave-assisted extraction of botanical materials: options and opportunities with chemometric tools.

    PubMed

    Das, Anup Kumar; Mandal, Vivekananda; Mandal, Subhash C

    2014-01-01

    Extraction forms the very basic step in research on natural products for drug discovery. A poorly optimised and planned extraction methodology can jeopardise the entire mission. To provide a vivid picture of different chemometric tools and planning for process optimisation and method development in extraction of botanical material, with emphasis on microwave-assisted extraction (MAE) of botanical material. A review of studies involving the application of chemometric tools in combination with MAE of botanical materials was undertaken in order to discover what the significant extraction factors were. Optimising a response by fine-tuning those factors, experimental design or statistical design of experiment (DoE), which is a core area of study in chemometrics, was then used for statistical analysis and interpretations. In this review a brief explanation of the different aspects and methodologies related to MAE of botanical materials that were subjected to experimental design, along with some general chemometric tools and the steps involved in the practice of MAE, are presented. A detailed study on various factors and responses involved in the optimisation is also presented. This article will assist in obtaining a better insight into the chemometric strategies of process optimisation and method development, which will in turn improve the decision-making process in selecting influential extraction parameters. Copyright © 2013 John Wiley & Sons, Ltd.

  15. Recent studies of float and stall curves in controlled-clearance deadweight testers with a simple piston.

    PubMed

    Newhall, D H; Ogawa, I; Zilberstein, V

    1979-08-01

    The effect of piston rotation speed and fluid viscosity on the performance of free-piston gauges with a controlled clearance was studied as part of an experimental program aiming at the better evaluation of pressure by these primary pressure standards. Calculated effective area is shown to be greatly influenced by both speed of rotation and choice of a fluid. An optimum rpm resulting in the smallest possible uncertainty in effective area should be determined experimentally for each fluid and pressure range involved. When all the pertinent parameters are properly selected an appreciable improvement in accuracy can be achieved.

  16. 47 CFR 5.64 - Special provisions for satellite systems.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... Section 5.64 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL EXPERIMENTAL RADIO SERVICE... experimental satellite facilities may begin prior to Commission grant of an authorization. Such construction is..., applicants for an experimental authorization involving a satellite system must submit a description of the...

  17. Unsteady-State Heat Transfer Involving a Phase Change: An Example of a 'Project-Oriented' Undergraduate Laboratory.

    ERIC Educational Resources Information Center

    Sundberg, Donald C.; Someshwar, Arun V.

    1989-01-01

    Describes the structure of an in-depth laboratory project chemical engineering. Provides modeling work to guide experimentation and experimental work on heat transfer analysis. Discusses the experimental results and evaluation of the project. (YP)

  18. The Effect of Music on the Spirituality of Patients: A Systematic Review.

    PubMed

    Alvarenga, Willyane de Andrade; Leite, Ana Carolina Andrade Biaggi; Oliveira, Marina Sanches; Nascimento, Lucila Castanheira; Silva-Rodrigues, Fernanda Machado; Nunes, Michelle Darezzo Rodrigues; Carvalho, Emilia Campos de

    2018-06-01

    Although some studies have suggested that music can positively affect physical and psychological variables, few have evaluated its effects on spirituality. This study aimed to evaluate the effects of musical interventions on the spirituality of patients, regardless of diagnoses. This was a systematic literature review that followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) recommendations conducted through a relevant search of terms in six databases (PubMed, Web of Science, CINAHL, PsycINFO, ScienceDirect, and LILACS) without temporal delimitation. Experimental or quasi-experimental studies were included, involving participants regardless of diagnoses, to assess the effect of music on spirituality, either through musical intervention as music medicine or through music therapy. The methodological quality of included studies was evaluated using the Physiotherapy Evidence Database scale. A total of 147 studies were identified; 7 met the inclusion criteria. Five studies were randomized controlled trials involving six music therapists leading the musical intervention with the active participation of patients. The interventions used were heterogeneous. Three studies were associated with improved spirituality after the intervention. Four studies used measurements to evaluate spiritual well-being. This review did not allow ascertaining the positive impact of music intervention on spirituality in patients, which motivates further research.

  19. Enhancement of bone consolidation in mandibular distraction osteogenesis: a contemporary review of experimental studies involving adjuvant therapies.

    PubMed

    Hong, Paul; Boyd, Daniel; Beyea, Steven D; Bezuhly, Michael

    2013-07-01

    One of the major disadvantages of mandibular distraction osteogenesis (MDO) is the prolonged time required for consolidation of the regenerate bone. The objective of the present study is to perform a contemporary review of various adjuvant therapies to enhance bone consolidation in MDO. A PubMed search for articles related to MDO, along with the references of those articles, was performed. Inclusion and exclusion criteria were applied to all experimental studies assessing adjuvant therapies to enhance bone consolidation. A total of 1414 titles and abstracts were initially reviewed; 61 studies were included for full review. Many studies involved growth factors, hormones, pharmacological agents, gene therapy, and stem cells. Other adjuvant therapies included mechanical stimulation, laser therapy, and hyperbaric oxygen. Majority of the studies demonstrated positive bone healing effects and thus adjuvant therapies remain a viable strategy to enhance and hasten the consolidation period. Although most studies have demonstrated promising results, many questions still remain, such as optimal amount, timing, and delivery methods required to stimulate the most favorable bone regeneration. As well, further studies comparing various adjuvant therapies and documentation of long-term adverse effects are required prior to clinical application. Copyright © 2013 British Association of Plastic, Reconstructive and Aesthetic Surgeons. Published by Elsevier Ltd. All rights reserved.

  20. Sound transmission in the chest under surface excitation - An experimental and computational study with diagnostic applications

    PubMed Central

    Peng, Ying; Dai, Zoujun; Mansy, Hansen A.; Sandler, Richard H.; Balk, Robert A; Royston, Thomas. J

    2014-01-01

    Chest physical examination often includes performing chest percussion, which involves introducing sound stimulus to the chest wall and detecting an audible change. This approach relies on observations that underlying acoustic transmission, coupling, and resonance patterns can be altered by chest structure changes due to pathologies. More accurate detection and quantification of these acoustic alterations may provide further useful diagnostic information. To elucidate the physical processes involved, a realistic computer model of sound transmission in the chest is helpful. In the present study, a computational model was developed and validated by comparing its predictions with results from animal and human experiments which involved applying acoustic excitation to the anterior chest while detecting skin vibrations at the posterior chest. To investigate the effect of pathology on sound transmission, the computational model was used to simulate the effects of pneumothorax on sounds introduced at the anterior chest and detected at the posterior. Model predictions and experimental results showed similar trends. The model also predicted wave patterns inside the chest, which may be used to assess results of elastography measurements. Future animal and human tests may expand the predictive power of the model to include acoustic behavior for a wider range of pulmonary conditions. PMID:25001497

  1. Numerical model updating technique for structures using firefly algorithm

    NASA Astrophysics Data System (ADS)

    Sai Kubair, K.; Mohan, S. C.

    2018-03-01

    Numerical model updating is a technique used for updating the existing experimental models for any structures related to civil, mechanical, automobiles, marine, aerospace engineering, etc. The basic concept behind this technique is updating the numerical models to closely match with experimental data obtained from real or prototype test structures. The present work involves the development of numerical model using MATLAB as a computational tool and with mathematical equations that define the experimental model. Firefly algorithm is used as an optimization tool in this study. In this updating process a response parameter of the structure has to be chosen, which helps to correlate the numerical model developed with the experimental results obtained. The variables for the updating can be either material or geometrical properties of the model or both. In this study, to verify the proposed technique, a cantilever beam is analyzed for its tip deflection and a space frame has been analyzed for its natural frequencies. Both the models are updated with their respective response values obtained from experimental results. The numerical results after updating show that there is a close relationship that can be brought between the experimental and the numerical models.

  2. Implementation of thermoelectric module for cooling process of microscale experimental room

    NASA Astrophysics Data System (ADS)

    Gołebiowska, Justyna; Żelazna, Agnieszka; Zioło, Paweł

    2017-08-01

    Thermoelectric modules, also known as Peltier modules, are used for cooling small devices and also, according to literature, in refrigeration. They can be an alternative to conventional refrigeration systems based on the use of compressors chillers powered by AC power. Peltier modules are powered by direct current (DC), which allows to power them directly supply by photovoltaic modules. In this paper operation of thermoelectric module used for cooling experimental room of cubature 0.125 m3 is presented. The study involves investigation of temperatures achieved on the cold and hot sides of module and inside the experimental room depending on the values of module supplying current. These studies provide an introduction to the assessment of the influence of different methods of heat removal on the hot side of thermoelectric module on cooling efficiency of whole system.

  3. Investigating true and false confessions within a novel experimental paradigm.

    PubMed

    Russano, Melissa B; Meissner, Christian A; Narchet, Fadia M; Kassin, Saul M

    2005-06-01

    The primary goal of the current study was to develop a novel experimental paradigm with which to study the influence of psychologically based interrogation techniques on the likelihood of true and false confessions. The paradigm involves guilty and innocent participants being accused of intentionally breaking an experimental rule, or "cheating." In the first demonstration of this paradigm, we explored the influence of two common police interrogation tactics: minimization and an explicit offer of leniency, or a "deal." Results indicated that guilty persons were more likely to confess than innocent persons, and that the use of minimization and the offer of a deal increased the rate of both true and false confessions. Police investigators are encouraged to avoid interrogation techniques that imply or directly promise leniency, as they appear to reduce the diagnostic value of any confession that is elicited.

  4. Mixing fuel particles for space combustion research using acoustics

    NASA Technical Reports Server (NTRS)

    Burns, Robert J.; Johnson, Jerome A.; Klimek, Robert B.

    1988-01-01

    Part of the microgravity science to be conducted aboard the Shuttle (STS) involves combustion using solids, particles, and liquid droplets. The central experimental facts needed for characterization of premixed quiescent particle cloud flames cannot be adequately established by normal gravity studies alone. The experimental results to date of acoustically mixing a prototypical particulate, lycopodium, in a 5 cm diameter by 75 cm long flame tube aboard a Learjet aircraft flying a 20 sec low gravity trajectory are described. Photographic and light detector instrumentation combine to measure and characterize particle cloud uniformity.

  5. Mixing fuel particles for space combustion research using acoustics

    NASA Technical Reports Server (NTRS)

    Burns, Robert J.; Johnson, Jerome A.; Klimek, Robert B.

    1988-01-01

    Part of the microgravity science to be conducted aboard the Shuttle (STS) involves combustion using solids, particles, and liquid droplets. The central experimental facts needed for characterization of premixed quiescent particle cloud flames cannot be adequately established by normal gravity studies alone. The experimental results to date of acoustically mixing a prototypical particulate, lycopodium, in a 5 cm diameter by 75 cm long flame tube aboard a Learjet aircraft flying a 20-sec low-gravity trajectory are described. Photographic and light detector instrumentation combine to measure and characterize particle cloud uniformity.

  6. Nature plus nurture: the triggering of multiple sclerosis.

    PubMed

    Wekerle, Hartmut

    2015-01-01

    Recent clinical and experimental studies indicate that multiple sclerosis develops as consequence of a failed interplay between genetic ("nature") and environmental ("nurture") factors. A large number of risk genes favour an autoimmune response against the body's own brain matter. New experimental data indicate that the actual trigger of this attack is however provided by an interaction of brain-specific immune cells with components of the regular commensal gut flora, the intestinal microbiota. This concept opens the way for new therapeutic approaches involving modulation of the microbiota by dietary or antibiotic regimens.

  7. Wavelength dependence of picosecond laser-induced periodic surface structures on copper

    NASA Astrophysics Data System (ADS)

    Maragkaki, Stella; Derrien, Thibault J.-Y.; Levy, Yoann; Bulgakova, Nadezhda M.; Ostendorf, Andreas; Gurevich, Evgeny L.

    2017-09-01

    The physical mechanisms of the laser-induced periodic surface structures (LIPSS) formation are studied in this paper for single-pulse irradiation regimes. The change in the LIPSS period with wavelength of incident laser radiation is investigated experimentally, using a picosecond laser system, which provides 7-ps pulses in near-IR, visible, and UV spectral ranges. The experimental results are compared with predictions made under the assumption that the surface-scattered waves are involved in the LIPSS formation. Considerable disagreement suggests that hydrodynamic mechanisms can be responsible for the observed pattern periodicity.

  8. Buoyancy-Driven Instabilities in Single-Bubble Sonoluminescence

    NASA Technical Reports Server (NTRS)

    Matula, Thomas J.

    2003-01-01

    The principal objectives of this study are to determine how gravity affects the emission of light from single-bubble sonoluminescence (SBSL), and whether or not the bubble extinction is directly related to gravity. Our experimental task involves designing glass or quartz spherical levitation cells that generate very stable SL bubbles. The cells must have minimized vibration, and some temperature control. The experimental system will reside in a light-tight enclosure. Aside from acceleration, the frequency, pressure amplitude, and light intensity must be measured. A computer program will be constructed to perform all aspects of the experiment.

  9. Investigation of Proprioceptor Stimulation.

    ERIC Educational Resources Information Center

    Caukins, Sivan E.; And Others

    A research proposal to study the effect of multisensory teaching methods in first-grade reading is presented. The focus is on sex differences in learning and in multisensory approaches to teaching. The project will involve 10 experimental and 10 control first-grade classes in several Southern California schools. Both groups will be given IQ,…

  10. Ethnicity and Me: An Experimental Unit.

    ERIC Educational Resources Information Center

    Smith, Gary R.

    This secondary social studies unit, part one of a series of four, contains 22 classroom activities that involve students in discovering their ethnicity. Students examine their attitudes toward ethnic groups, particularly African Americans, Irish Americans, Arab Americans, and Mexican Americans. The activities can easily be integrated into U.S.…

  11. Plant-soil feedbacks and mycorrhizal type influence temperate forest population dynamics

    USDA-ARS?s Scientific Manuscript database

    Feedback with soil biota is a major driver of diversity within terrestrial plant communities. However, little is known about the factors regulating plant-soil feedback, which can vary from positive to negative among plant species. In a large-scale observational and experimental study involving 55 sp...

  12. Classroom Questioning with Immediate Electronic Response: Do Clickers Improve Learning?

    ERIC Educational Resources Information Center

    Yourstone, Steven A.; Kraye, Howard S.; Albaum, Gerald

    2008-01-01

    A number of studies have focused on how students and instructors feel about digital learning technologies. This research is focused on the substantive difference in learning outcomes between traditional classrooms and classrooms using clickers. A randomized block experimental design involving four sections of undergraduate Operations Management…

  13. What Stands and Develops between Creative and Critical Thinking? Argumentation?

    ERIC Educational Resources Information Center

    Glassner, Amnon; Schwarz, Baruch B.

    2007-01-01

    Creative and critical thinking have been traditionally considered as involving independent skills and dispositions. However the definition of critical thinking has been gradually reconsidered to include skills and dispositions through which one opens new links instead of scrutinizing existing links in a closed analysis. Experimental studies have…

  14. Music during Lectures: Will Students Learn Better?

    ERIC Educational Resources Information Center

    Dosseville, Fabrice; Laborde, Sylvain; Scelles, Nicolas

    2012-01-01

    We investigated the influence of music during learning on the academic performance of undergraduate students, and more particularly the influence of affects induced by music. Altogether 249 students were involved in the study, divided into a control group and an experimental group. Both groups attended the same videotaped lecture, with the…

  15. Effects of Technology Immersion on Middle School Students' Learning Opportunities and Achievement

    ERIC Educational Resources Information Center

    Shapley, Kelly; Sheehan, Daniel; Maloney, Catherine; Caranikas-Walker, Fanny

    2011-01-01

    An experimental study of the Technology Immersion model involved comparisons between 21 middle schools that received laptops for each teacher and student, instructional and learning resources, professional development, and technical and pedagogical support, and 21 control schools. Using hierarchical linear modeling to analyze longitudinal survey…

  16. Developing Mathematical Fluency: Comparing Exercises and Rich Tasks

    ERIC Educational Resources Information Center

    Foster, Colin

    2018-01-01

    Achieving fluency in important mathematical procedures is fundamental to students' mathematical development. The usual way to develop procedural fluency is to practise repetitive exercises, but is this the only effective way? This paper reports three quasi-experimental studies carried out in a total of 11 secondary schools involving altogether 528…

  17. Human Behavior: Do Animals Have the Answer

    ERIC Educational Resources Information Center

    Trotter, Robert J.

    1974-01-01

    Results of psychological experiments usinganimals are presented. Use of the animal-human analogy to generalize these findings to humans is discussed. Ethological studies are interpreted in light of the total environment and situation involved. The completeness of the ethological model compared to the animal-experimental model is discussed. (LS)

  18. A Pilot Study of Marital Therapy as a Treatment for Depression.

    ERIC Educational Resources Information Center

    Waring, Edward M.; And Others

    1995-01-01

    Seventeen depressed, married women were assigned to marital therapy or a waiting list control group. Couples received 10 sessions of Enhancing Marital Intimacy Therapy (EMIT), a structured technique involving the self-disclosure of personal constructs. Comparisons revealed a significant reduction in the experimental group's depressive…

  19. Sex Parties: Female Teen Sexual Experimentation

    ERIC Educational Resources Information Center

    Toscano, Sharyl Eve

    2006-01-01

    Adolescent participants in a study aimed at exploring the nature and characteristics of girls' dating relationships revealed the phenomenon of sex parties. These teens defined a "sex party" as an opportunity to engage in sexual contact outside of typical dating relationships. Sexual activity could involve actual intercourse, but usually involved…

  20. An Experimental Evaluation of Hyperactivity and Food Additives. 1977-Phase I.

    ERIC Educational Resources Information Center

    Harley, J. Preston

    Reported are findings of a study involving 46 families in which the effect of the Feingold (additive free) diet on hyperactivity in preschool and elementary age children was investigated. Eleven sections cover the following project components: introduction (definition of hyperactivity and the B. Feingold hypothesis), methodology, demographic…

  1. Experimental Design and Some Threats to Experimental Validity: A Primer

    ERIC Educational Resources Information Center

    Skidmore, Susan

    2008-01-01

    Experimental designs are distinguished as the best method to respond to questions involving causality. The purpose of the present paper is to explicate the logic of experimental design and why it is so vital to questions that demand causal conclusions. In addition, types of internal and external validity threats are discussed. To emphasize the…

  2. OpenKnowledge for peer-to-peer experimentation in protein identification by MS/MS

    PubMed Central

    2011-01-01

    Background Traditional scientific workflow platforms usually run individual experiments with little evaluation and analysis of performance as required by automated experimentation in which scientists are being allowed to access numerous applicable workflows rather than being committed to a single one. Experimental protocols and data under a peer-to-peer environment could potentially be shared freely without any single point of authority to dictate how experiments should be run. In such environment it is necessary to have mechanisms by which each individual scientist (peer) can assess, locally, how he or she wants to be involved with others in experiments. This study aims to implement and demonstrate simple peer ranking under the OpenKnowledge peer-to-peer infrastructure by both simulated and real-world bioinformatics experiments involving multi-agent interactions. Methods A simulated experiment environment with a peer ranking capability was specified by the Lightweight Coordination Calculus (LCC) and automatically executed under the OpenKnowledge infrastructure. The peers such as MS/MS protein identification services (including web-enabled and independent programs) were made accessible as OpenKnowledge Components (OKCs) for automated execution as peers in the experiments. The performance of the peers in these automated experiments was monitored and evaluated by simple peer ranking algorithms. Results Peer ranking experiments with simulated peers exhibited characteristic behaviours, e.g., power law effect (a few dominant peers dominate), similar to that observed in the traditional Web. Real-world experiments were run using an interaction model in LCC involving two different types of MS/MS protein identification peers, viz., peptide fragment fingerprinting (PFF) and de novo sequencing with another peer ranking algorithm simply based on counting the successful and failed runs. This study demonstrated a novel integration and useful evaluation of specific proteomic peers and found MASCOT to be a dominant peer as judged by peer ranking. Conclusion The simulated and real-world experiments in the present study demonstrated that the OpenKnowledge infrastructure with peer ranking capability can serve as an evaluative environment for automated experimentation. PMID:22192521

  3. A Quasi-Experimental Study of a Blended Course Integrated with Refined Web-Mediated Pedagogy of Collaborative Learning and Self-Regulated Learning

    ERIC Educational Resources Information Center

    Tsai, Chia-Wen

    2014-01-01

    Innovative teaching methods integrated with web technologies have been increasingly used in higher education. However, there are few studies discussing effective web-mediated teaching methods for both students and teachers. To help students learn and develop their academic involvement in a blended course, and improve their thoughts regarding this…

  4. Error Detection and Self-Assessment as Mechanisms to Promote Self-Regulation of Learning among Secondary Education Students

    ERIC Educational Resources Information Center

    Zamora, Ángela; Suárez, José Manuel; Ardura, Diego

    2018-01-01

    The authors' objective was to study the role of error detection and retroactive self-regulation as determinants of performance in secondary education students. A total of 198 students participated in the quasiexperimental study, which involved a control group and two experimental groups. This enabled the authors to analyze the effects of both…

  5. Effects of a Target-Task Problem-Solving Model on Senior Secondary School Students' Performance in Physics

    ERIC Educational Resources Information Center

    Olaniyan, A. O.; Omosewo, E. O.

    2015-01-01

    The study investigated the Effects of a Target-Task Problem-Solving Model on Senior Secondary School Students' Performance in Physics. The research design was a quasi-experimental, non-randomized, non-equivalent pretest, post-test using a control group. The study was conducted in two schools purposively selected and involved a total of 120 Senior…

  6. The Effect of a Suggested Multisensory Phonics Program on Developing Kindergarten Pre-Service Teachers' EFL Reading Accuracy and Phonemic Awareness

    ERIC Educational Resources Information Center

    Ghoneim, Nahed Mohammed Mahmoud; Elghotmy, Heba Elsayed Abdelsalam

    2015-01-01

    The current study investigates the effect of a suggested multisensory phonics program on developing kindergarten pre-service teachers' EFL reading accuracy and phonemic awareness. A total of 40 fourth year kindergarten pre-service teachers, Faculty of Education, participated in the study that involved one group experimental design. Pre-post tests…

  7. The Effect of Inquiry-Based Learning Method on Students' Academic Achievement in Science Course

    ERIC Educational Resources Information Center

    Abdi, Ali

    2014-01-01

    The purpose of this study was to investigate the effects of inquiry-based learning method on students' academic achievement in sciences lesson. A total of 40 fifth grade students from two different classes were involved in the study. They were selected through purposive sampling method. The group which was assigned as experimental group was…

  8. Gender Differences in Mathematics Achievement and Retention Scores: A Case of Problem-Based Learning Method

    ERIC Educational Resources Information Center

    Ajai, John T.; Imoko, Benjamin I.

    2015-01-01

    This study was undertaken to assess gender differences in mathematics achievement and retention by using Problem-Based Learning (PBL). The design of the study was pre-posttest quasi-experimental. Four hundred and twenty eight senior secondary one (SS I) students using multistage sampling from ten grant-aided and government schools were involved in…

  9. Effects of the Wisconsin Reading Design Comprehension Program on Reading Achievement and Self-Concept of Sixth Grade Students.

    ERIC Educational Resources Information Center

    Negley, Sandra Anne

    The main purpose of this study was to determine and describe the effects of the comprehension component of the criterion-referenced reading program, Wisconsin Design for Reading Skills Development (WDRSD), on reading achievement and self-concept of sixth-grade students. Parametric techniques were employed in a quasi-experimental study involving 44…

  10. Effectiveness of Blended Learning and Elearning Modes of Instruction on the Performance of Undergraduates in Kwara State, Nigeria

    ERIC Educational Resources Information Center

    Gambari, Amosa Isiaka; Shittu, Ahmed Tajudeen; Ogunlade, O. Olufunmilola; Osunlade, Olourotimi Rufus

    2017-01-01

    This study investigated the effectiveness of blended learning and E-learning modes of instruction on the performance of undergraduates in Kwara State, Nigeria. It also determined if the student performance would vary with gender. Quasi experimental that employs pretest, posttest, control group design was adopted for this study. This involves three…

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

    ERIC Educational Resources Information Center

    Carrejo, David J.; Marshall, Jill

    2007-01-01

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

  12. AICE Survey of USSR Air Pollution Literature, Volume 13: Technical Papers from the Leningrad International Symposium on the Meteorological Aspects of Atmospheric Pollution, Part 2.

    ERIC Educational Resources Information Center

    Nuttonson, M. Y., Ed.

    Twelve papers were translated from Russian: Automation of Information Processing Involved in Experimental Studies of Atmospheric Diffusion, Micrometeorological Characteristics of Atmospheric Pollution Conditions, Study of theInfluence of Irregularities of the Earth's Surface on the Air Flow Characteristics in a Wind Tunnel, Use of Parameters of…

  13. Conceptual Understanding of Acids and Bases Concepts and Motivation to Learn Chemistry

    ERIC Educational Resources Information Center

    Cetin-Dindar, Ayla; Geban, Omer

    2017-01-01

    The purpose of this study was to investigate the effect of 5E learning cycle model oriented instruction (LCMI) on 11th-grade students' conceptual understanding of acids and bases concepts and student motivation to learn chemistry. The study, which lasted for 7 weeks, involved two groups: An experimental group (LCMI) and a control group (the…

  14. Analysis of castellated steel beam with oval openings

    NASA Astrophysics Data System (ADS)

    Tudjono, S.; Sunarto; Han, A. L.

    2017-11-01

    A castellated steel beam is per definition a wide flange (WF) or I shaped steel profile with openings, to reduce self-weight and improve the effectiveness in terms of material use. Recently, extensive study on these castellated steel beams has been conducted, involving different shapes in web openings. The main goal of these research works was to evaluate and analyze its optimum opening sizes and shapes configuration. More in-depth research work to the behavior and the influence of holes to WF beams need to be conducted. In this paper, an oval shaped web opening is chosen as alternate. The study involves a modification in the variation of oval web openings both in the horizontally and vertically direction. An experimental and numerical study based on the finite element method conducted with the Abaqus/CAE 6.12 software is used to analyze the buckling behavior of the web. The obtained results from the experimental test specimens are in good agreement with the obtained results from the finite element analysis. Furthermore, the numerical model can be expanded to be used as analyzing tool in evaluating and studying the effect and influencing factors of a variation in opening’s parameters.

  15. Sustained hyperhydration with glycerol ingestion.

    PubMed

    Koenigsberg, P S; Martin, K K; Hlava, H R; Riedesel, M L

    1995-01-01

    Heavy exercise lasting more than three hours tends to result in dehydration, as the fluid intake is less than fluid loss by sweat and urine. Dehydration as small as one percent of body weight has been reported to decrease work capacity. In present and previous studies insensible water loss and sweat are assumed to be the same in both control and experimental conditions. Fluid intake less urine volume is utilized as an indicator of euhydration, hypohydration, or hyperhydration. Previous studies involving glycerol intake describe hyperhydration for 4.5 to 8 hours. The objective of this study was to keep subjects hyperhydrated (retention of water) for 32 or 49 hours. The experimental protocol involved ingestion of a large volume of fluid (39.2 or 51.1 ml/kg/d) with glycerol (2.9 to 3.1 g/kg/d) and without glycerol. In both Series I (49 h) and Series II (32 h) experiments, the intake of glycerol resulted in smaller urine volumes. This study demonstrates it is possible to keep human subjects hyperhydrated for extended periods of time and thereby reduce the amount of fluid consumption necessary just prior to or during bouts of negative fluid balance situations.

  16. A loop-gap resonator for chirality-sensitive nuclear magneto-electric resonance (NMER)

    NASA Astrophysics Data System (ADS)

    Garbacz, Piotr; Fischer, Peer; Krämer, Steffen

    2016-09-01

    Direct detection of molecular chirality is practically impossible by methods of standard nuclear magnetic resonance (NMR) that is based on interactions involving magnetic-dipole and magnetic-field operators. However, theoretical studies provide a possible direct probe of chirality by exploiting an enantiomer selective additional coupling involving magnetic-dipole, magnetic-field, and electric field operators. This offers a way for direct experimental detection of chirality by nuclear magneto-electric resonance (NMER). This method uses both resonant magnetic and electric radiofrequency (RF) fields. The weakness of the chiral interaction though requires a large electric RF field and a small transverse RF magnetic field over the sample volume, which is a non-trivial constraint. In this study, we present a detailed study of the NMER concept and a possible experimental realization based on a loop-gap resonator. For this original device, the basic principle and numerical studies as well as fabrication and measurements of the frequency dependence of the scattering parameter are reported. By simulating the NMER spin dynamics for our device and taking the 19F NMER signal of enantiomer-pure 1,1,1-trifluoropropan-2-ol, we predict a chirality induced NMER signal that accounts for 1%-5% of the standard achiral NMR signal.

  17. Studying the neurobiology of human social interaction: Making the case for ecological validity.

    PubMed

    Hogenelst, Koen; Schoevers, Robert A; aan het Rot, Marije

    2015-01-01

    With this commentary we make the case for an increased focus on the ecological validity of the measures used to assess aspects of human social functioning. Impairments in social functioning are seen in many types of psychopathology, negatively affecting the lives of psychiatric patients and those around them. Yet the neurobiology underlying abnormal social interaction remains unclear. As an example of human social neuroscience research with relevance to biological psychiatry and clinical psychopharmacology, this commentary discusses published experimental studies involving manipulation of the human brain serotonin system that included assessments of social behavior. To date, these studies have mostly been laboratory-based and included computer tasks, observations by others, or single-administration self-report measures. Most laboratory measures used so far inform about the role of serotonin in aspects of social interaction, but the relevance for real-life interaction is often unclear. Few studies have used naturalistic assessments in real life. We suggest several laboratory methods with high ecological validity as well as ecological momentary assessment, which involves intensive repeated measures in naturalistic settings. In sum, this commentary intends to stimulate experimental research on the neurobiology of human social interaction as it occurs in real life.

  18. The Effect of Visual of a Courseware towards Pre-University Students' Learning in Literature

    NASA Astrophysics Data System (ADS)

    Masri, Mazyrah; Wan Ahmad, Wan Fatimah; Nordin, Shahrina Md.; Sulaiman, Suziah

    This paper highlights the effect of visual of a multimedia courseware, Black Cat Courseware (BC-C), developed for learning literature at a pre-university level in University Teknologi PETRONAS (UTP). The contents of the courseware are based on a Black Cat story which is covered in an English course at the university. The objective of this paper is to evaluate the usability and effectiveness of BC-C. A total of sixty foundation students were involved in the study. Quasi-experimental design was employed, forming two groups: experimental and control groups. The experimental group had to interact with BC-C as part of the learning activities while the control group used the conventional learning methods. The results indicate that the experimental group achieved a statistically significant compared to the control group in understanding the Black Cat story. The study result also proves that the effect of visual increases the students' performances in literature learning at a pre-university level.

  19. Studies on the Parametric Effects of Plasma Arc Welding of 2205 Duplex Stainless Steel

    NASA Astrophysics Data System (ADS)

    Selva Bharathi, R.; Siva Shanmugam, N.; Murali Kannan, R.; Arungalai Vendan, S.

    2018-03-01

    This research study attempts to create an optimized parametric window by employing Taguchi algorithm for Plasma Arc Welding (PAW) of 2 mm thick 2205 duplex stainless steel. The parameters considered for experimentation and optimization are the welding current, welding speed and pilot arc length respectively. The experimentation involves the parameters variation and subsequently recording the depth of penetration and bead width. Welding current of 60-70 A, welding speed of 250-300 mm/min and pilot arc length of 1-2 mm are the range between which the parameters are varied. Design of experiments is used for the experimental trials. Back propagation neural network, Genetic algorithm and Taguchi techniques are used for predicting the bead width, depth of penetration and validated with experimentally achieved results which were in good agreement. Additionally, micro-structural characterizations are carried out to examine the weld quality. The extrapolation of these optimized parametric values yield enhanced weld strength with cost and time reduction.

  20. Equilibrium expert: an add-in to Microsoft Excel for multiple binding equilibrium simulations and parameter estimations.

    PubMed

    Raguin, Olivier; Gruaz-Guyon, Anne; Barbet, Jacques

    2002-11-01

    An add-in to Microsoft Excel was developed to simulate multiple binding equilibriums. A partition function, readily written even when the equilibrium is complex, describes the experimental system. It involves the concentrations of the different free molecular species and of the different complexes present in the experiment. As a result, the software is not restricted to a series of predefined experimental setups but can handle a large variety of problems involving up to nine independent molecular species. Binding parameters are estimated by nonlinear least-square fitting of experimental measurements as supplied by the user. The fitting process allows user-defined weighting of the experimental data. The flexibility of the software and the way it may be used to describe common experimental situations and to deal with usual problems such as tracer reactivity or nonspecific binding is demonstrated by a few examples. The software is available free of charge upon request.

  1. Preventing Substance Abuse among Black and Hispanic Adolescent Girls: Results from a Computer-Delivered, Mother-Daughter Intervention Approach

    PubMed Central

    Schinke, Steven P.; Fang, Lin; Cole, Kristin C. A.

    2010-01-01

    This 2008 study involved 546 Black- and Hispanic-American adolescent girls and their mothers from New York, New Jersey, and Connecticut. Participants provided self-report data. Analysis of covariance indicated that the experimental intervention reduced risk factors, improved protective factors, and lowered girls' alcohol use and their future intentions to use substances. The study supports the value of computer-based and gender-specific interventions that involve girls and mothers. Future work needs to replicate and strengthen study results. Research support came from the National Institute on Drug Abuse within the National Institutes of Health of the United States Public Health Service. PMID:21190404

  2. Semi-empirical quantum evaluation of peptide - MHC class II binding

    NASA Astrophysics Data System (ADS)

    González, Ronald; Suárez, Carlos F.; Bohórquez, Hugo J.; Patarroyo, Manuel A.; Patarroyo, Manuel E.

    2017-01-01

    Peptide presentation by the major histocompatibility complex (MHC) is a key process for triggering a specific immune response. Studying peptide-MHC (pMHC) binding from a structural-based approach has potential for reducing the costs of investigation into vaccine development. This study involved using two semi-empirical quantum chemistry methods (PM7 and FMO-DFTB) for computing the binding energies of peptides bonded to HLA-DR1 and HLA-DR2. We found that key stabilising water molecules involved in the peptide binding mechanism were required for finding high correlation with IC50 experimental values. Our proposal is computationally non-intensive, and is a reliable alternative for studying pMHC binding interactions.

  3. Carbothermic Synthesis of 820 m UN Kernels: Literature Review, Thermodynamics, Analysis, and Related Experiments

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

    Lindemer, Terrence; Voit, Stewart L; Silva, Chinthaka M

    2014-01-01

    The U.S. Department of Energy is considering a new nuclear fuel that would be less susceptible to ruptures during a loss-of-coolant accident. The fuel would consist of tristructural isotropic coated particles with large, dense uranium nitride (UN) kernels. This effort explores many factors involved in using gel-derived uranium oxide-carbon microspheres to make large UN kernels. Analysis of recent studies with sufficient experimental details is provided. Extensive thermodynamic calculations are used to predict carbon monoxide and other pressures for several different reactions that may be involved in conversion of uranium oxides and carbides to UN. Experimentally, the method for making themore » gel-derived microspheres is described. These were used in a microbalance with an attached mass spectrometer to determine details of carbothermic conversion in argon, nitrogen, or vacuum. A quantitative model is derived from experiments for vacuum conversion to an uranium oxide-carbide kernel.« less

  4. Experimental Measurements of Heat Transfer through a Lunar Regolith Simulant in a Vibro-Fluidized Reactor Oven

    NASA Technical Reports Server (NTRS)

    Nayagam, Vedha; Berger, Gordon M.; Sacksteder, Kurt R.; Paz, Aaron

    2012-01-01

    Extraction of mission consumable resources such as water and oxygen from the planetary environment provides valuable reduction in launch-mass and potentially extends the mission duration. Processing of lunar regolith for resource extraction necessarily involves heating and chemical reaction of solid material with processing gases. Vibrofluidization is known to produce effective mixing and control of flow within granular media. In this study we present experimental results for vibrofluidized heat transfer in lunar regolith simulants (JSC-1 and JSC-1A) heated up to 900 C. The results show that the simulant bed height has a significant influence on the vibration induced flow field and heat transfer rates. A taller bed height leads to a two-cell circulation pattern whereas a single-cell circulation was observed for a shorter height. Lessons learned from these test results should provide insight into efficient design of future robotic missions involving In-Situ Resource Utilization.

  5. Could Perinatal Asphyxia Induce a Synaptopathy? New Highlights from an Experimental Model

    PubMed Central

    Herrera, María Inés; Udovin, Lucas Daniel; Kusnier, Carlos; Kölliker-Frers, Rodolfo; de Souza, Wanderley

    2017-01-01

    Birth asphyxia also termed perinatal asphyxia is an obstetric complication that strongly affects brain structure and function. Central nervous system is highly susceptible to oxidative damage caused by perinatal asphyxia while activation and maturity of the proper pathways are relevant to avoiding abnormal neural development. Perinatal asphyxia is associated with high morbimortality in term and preterm neonates. Although several studies have demonstrated a variety of biochemical and molecular pathways involved in perinatal asphyxia physiopathology, little is known about the synaptic alterations induced by perinatal asphyxia. Nearly 25% of the newborns who survive perinatal asphyxia develop neurological disorders such as cerebral palsy and certain neurodevelopmental and learning disabilities where synaptic connectivity disturbances may be involved. Accordingly, here we review and discuss the association of possible synaptic dysfunction with perinatal asphyxia on the basis of updated evidence from an experimental model. PMID:28326198

  6. Deleterious Effects of Mycotoxin Combinations Involving Ochratoxin A

    PubMed Central

    Klarić, Maja Šegvić; Rašić, Dubravka; Peraica, Maja

    2013-01-01

    Ochratoxin A (OTA) is a nephrotoxic mycotoxin with carcinogenic properties. Its presence was detected in various foodstuffs all over the world but with significantly higher frequency and concentrations in areas with endemic nephropathy (EN). Even though food is often contaminated with more than one mycotoxin, earlier studies focused on the occurrence and toxicology of only OTA. Only a limited number of surveys showed that OTA co-occurs in food with mycotoxins (citrinin-CIT, penicilic acid, fumonisin B1-FB1, aflatoxins-AF) which exert nephrotoxic, carcinogenic or carcinogen-promoting activity. This review summarises the findings on OTA and its co-occurrence with the mentioned mycotoxins in food as well as experimental data on their combined toxicity. Most of the tested mycotoxin mixtures involving OTA produced additive or synergistic effects in experimental models suggesting that these combinations represent a significant health hazard. Special attention should be given to mixtures that include carcinogenic and cancer-promoting mycotoxins. PMID:24189375

  7. Decreasing Risky Behavior on Social Network Sites: The Impact of Parental Involvement in Secondary Education Interventions.

    PubMed

    Vanderhoven, Ellen; Schellens, Tammy; Valcke, Martin

    2016-06-01

    Teenagers face significant risks when using increasingly popular social network sites. Prevention and intervention efforts to raise awareness about these risks and to change risky behavior (so-called "e-safety" interventions) are essential for the wellbeing of these minors. However, several studies have revealed that while school interventions often affect awareness, they have only a limited impact on pupils' unsafe behavior. Utilizing the Theory of Planned Behavior and theories about parental involvement, we hypothesized that involving parents in an e-safety intervention would positively influence pupils' intentions and behavior. In a quasi-experimental study with pre- and post-test measures involving 207 pupils in secondary education, we compared the impact of an intervention without parental involvement with one that included active parental involvement by means of a homework task. We found that whereas parental involvement was not necessary to improve the intervention's impact on risk awareness, it did change intentions to engage in certain unsafe behavior, such as posting personal and sexual information on the profile page of a social network site, and in reducing existing problematic behavior. This beneficial impact was particularly evident for boys. These findings suggest that developing prevention campaigns with active parental involvement is well worth the effort. Researchers and developers should therefore focus on other efficient strategies to involve parents.

  8. In pursuit of precision: the calibration of minds and machines in late nineteenth-century psychology.

    PubMed

    Benschop, R; Draaisma, D

    2000-01-01

    A prominent feature of late nineteenth-century psychology was its intense preoccupation with precision. Precision was at once an ideal and an argument: the quest for precision helped psychology to establish its status as a mature science, sharing a characteristic concern with the natural sciences. We will analyse how psychologists set out to produce precision in 'mental chronometry', the measurement of the duration of psychological processes. In his Leipzig laboratory, Wundt inaugurated an elaborate research programme on mental chronometry. We will look at the problem of calibration of experimental apparatus and will describe the intricate material, literary, and social technologies involved in the manufacture of precision. First, we shall discuss some of the technical problems involved in the measurement of ever shorter time-spans. Next, the Cattell-Berger experiments will help us to argue against the received view that all the precision went into the hardware, and practically none into the social organization of experimentation. Experimenters made deliberate efforts to bring themselves and their subjects under a regime of control and calibration similar to that which reigned over the experimental machinery. In Leipzig psychology, the particular blend of material and social technology resulted in a specific object of study: the generalized mind. We will then show that the distribution of precision in experimental psychology outside Leipzig demanded a concerted effort of instruments, texts, and people. It will appear that the forceful attempts to produce precision and uniformity had some rather paradoxical consequences.

  9. Training informal caregivers to care for older people after stroke: a quasi-experimental study.

    PubMed

    Araújo, Odete; Lage, Isabel; Cabrita, José; Teixeira, Laetitia

    2018-05-12

    The present study aimed at evaluating whether training on practical skills involved in providing care reduces the burden experienced by informal caregivers and improves their general health condition. A substantial number of informal caregivers lack skills to deliver post-stroke assistance to older people after hospital discharge, which leads to burden situations as well as mental and physical health deterioration of the former. A quasi-experimental design. This study involved 174 informal caregivers of older people who overcame a stroke. The control group (N= 89) received the usual type of care delivered in healthcare units. The experimental group (N=85) adopted the InCARE programme for 1 week (T0), 1 month (T1) and 3 (T2) months and received telephone support by counselling caregivers on the subsequent 3rd, 6th, 8th and 10th weeks to hospital discharge. It aimed at facilitating the caregiver's adjustment to the demands of a post- stroke stage and at increasing knowledge and practical skills to support the decision making. Data collection occurred between February - December 2014 at the Community Home Care Services in northern Portugal. The experimental group obtained significantly better results regarding practical skills as well as lower burden levels and a better general mental health condition when compared with the control group 1 (T1) and 3 (T2) months after intervention. Findings suggest that our programme improved practical skills, helped reduce burden levels with better scores and improvement regarding general mental health condition of informal caregivers. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  10. Understanding the effectiveness of the entertainment-education strategy: an investigation of how audience involvement, message processing, and message design influence health information recall.

    PubMed

    Quintero Johnson, Jessie M; Harrison, Kristen; Quick, Brian L

    2013-01-01

    A growing body of evidence suggests that entertainment-education (EE) is a promising health communication strategy. The purpose of this study was to identify some of the factors that facilitate and hinder audience involvement with EE messages. Using confirmatory factor analysis, the authors introduce a construct they call experiential involvement, which describes the experience of being cognitively and emotionally involved with EE messages and is a product of transportation into an EE text and identification with EE characters. Using an experimental design, the authors also investigated how reports of experiential involvement and health information recall varied depending on the degree to which the educational content was well integrated with the narrative content in EE messages. Findings indicated that integration significantly influenced health information recall. Results indicated that experiential involvement and the perception that the health topic in EE messages was personally relevant predicted participants' systematic processing of the information in EE messages. Contrary to expectation, personal relevance did not predict experiential involvement, and systematic message processing was negatively related to health information recall. Implications for the construction of EE messages and the study of the EE strategy are discussed.

  11. Experimental study designs to improve the evaluation of road mitigation measures for wildlife.

    PubMed

    Rytwinski, Trina; van der Ree, Rodney; Cunnington, Glenn M; Fahrig, Lenore; Findlay, C Scott; Houlahan, Jeff; Jaeger, Jochen A G; Soanes, Kylie; van der Grift, Edgar A

    2015-05-01

    An experimental approach to road mitigation that maximizes inferential power is essential to ensure that mitigation is both ecologically-effective and cost-effective. Here, we set out the need for and standards of using an experimental approach to road mitigation, in order to improve knowledge of the influence of mitigation measures on wildlife populations. We point out two key areas that need to be considered when conducting mitigation experiments. First, researchers need to get involved at the earliest stage of the road or mitigation project to ensure the necessary planning and funds are available for conducting a high quality experiment. Second, experimentation will generate new knowledge about the parameters that influence mitigation effectiveness, which ultimately allows better prediction for future road mitigation projects. We identify seven key questions about mitigation structures (i.e., wildlife crossing structures and fencing) that remain largely or entirely unanswered at the population-level: (1) Does a given crossing structure work? What type and size of crossing structures should we use? (2) How many crossing structures should we build? (3) Is it more effective to install a small number of large-sized crossing structures or a large number of small-sized crossing structures? (4) How much barrier fencing is needed for a given length of road? (5) Do we need funnel fencing to lead animals to crossing structures, and how long does such fencing have to be? (6) How should we manage/manipulate the environment in the area around the crossing structures and fencing? (7) Where should we place crossing structures and barrier fencing? We provide experimental approaches to answering each of them using example Before-After-Control-Impact (BACI) study designs for two stages in the road/mitigation project where researchers may become involved: (1) at the beginning of a road/mitigation project, and (2) after the mitigation has been constructed; highlighting real case studies when available. Copyright © 2015 Elsevier Ltd. All rights reserved.

  12. Human cells involved in atherosclerosis have a sex.

    PubMed

    Franconi, Flavia; Rosano, Giuseppe; Basili, Stefania; Montella, Andrea; Campesi, Ilaria

    2017-02-01

    The influence of sex has been largely described in cardiovascular diseases. Atherosclerosis is a complex process that involves many cell types such as vessel cells, immune cells and endothelial progenitor cells; however, many, if not all, studies do not report the sex of the cells. This review focuses on sex differences in human cells involved in the atherosclerotic process, emphasizing the role of sex hormones. Furthermore, we report sex differences and issues related to the processes that determine the fate of the cells such as apoptotic and autophagic mechanisms. The analysis of the data reveals that there are still many gaps in our knowledge regarding sex influences in atherosclerosis, largely for the cell types that have not been well studied, stressing the urgent need for a clear definition of experimental conditions and the inclusion of both sexes in preclinical studies. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  13. Does the patient‐held record improve continuity and related outcomes in cancer care: a systematic review

    PubMed Central

    Gysels, Marjolein; Richardson, Alison; Higginson, Irene J.

    2006-01-01

    Abstract Objectives  To assess the effectiveness of the patient‐held record (PHR) in cancer care. Background  Patients with cancer may receive care from different services resulting in gaps. A PHR could provide continuity and patient involvement in care. Search strategy  Relevant literature was identified through five electronic databases (Medline, Embase, Cinahl, CCTR and CDSR) and hand searches. Inclusion criteria  Patient‐held records in cancer care with the purpose of improving communication and information exchange between and within different levels of care and to promote continuity of care and patients’ involvement in their own care. Data extraction and synthesis  Data extraction recorded characteristics of intervention, type of study and factors that contributed to methodological quality of individual studies. Data were then contrasted by setting, objectives, population, study design, outcome measures and changes in outcome, including knowledge, satisfaction, anxiety and depression. Methodological quality of randomized control trials and non‐experimental studies were assessed with separate standard grading scales. Main results and conclusions  Seven randomized control trials and six non‐experimental studies were identified. Evaluations of the PHR have reached equivocal findings. Randomized trials found an absence of effect, non‐experimental evaluations shed light on the conditions for its successful use. Most patients welcomed introduction of a PHR. Main problems related to its suitability for different patient groups and the lack of agreement between patients and health professionals regarding its function. Further research is required to determine the conditions under which the PHR can realize its potential as a tool to promote continuity of care and patient participation. PMID:17324196

  14. Challenges for Preclinical Investigations of Human Biofield Modalities

    PubMed Central

    Gronowicz, Gloria; Bengston, William

    2015-01-01

    Preclinical models for studying the effects of the human biofield have great potential to advance our understanding of human biofield modalities, which include external qigong, Johrei, Reiki, therapeutic touch, healing touch, polarity therapy, pranic healing, and other practices. A short history of Western biofield studies using preclinical models is presented and demonstrates numerous and consistent examples of human biofields significantly affecting biological systems both in vitro and in vivo. Methodological issues arising from these studies and practical solutions in experimental design are presented. Important questions still left unanswered with preclinical models include variable reproducibility, dosing, intentionality of the practitioner, best preclinical systems, and mechanisms. Input from the biofield practitioners in the experimental design is critical to improving experimental outcomes; however, the development of standard criteria for uniformity of practice and for inclusion of multiple practitioners is needed. Research in human biofield studies involving preclinical models promises a better understanding of the mechanisms underlying the efficacy of biofield therapies and will be important in guiding clinical protocols and integrating treatments with conventional medical therapies. PMID:26665042

  15. T Cells

    MedlinePlus

    ... cells — have proven successful in treating animals with experimental allergic encephalomyelitis (EAE), an animal model of MS. Pilot clinical trials are in progress. Future experimental therapies may involve antibodies directed against the cytokines ...

  16. 78 FR 25436 - Pesticide Experimental Use Permits; Receipt of Applications; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-01

    ... ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-OPP-2013-0106; FRL-9385-4] Pesticide Experimental Use...: Notice. SUMMARY: This notice announces EPA's receipt of applications requesting experimental use permits... treatment and meaningful involvement of any group, including minority and/or low income populations, in the...

  17. Cooperative catalysis by tertiary amino-thioureas: mechanism and basis for enantioselectivity of ketone cyanosilylation.

    PubMed

    Zuend, Stephan J; Jacobsen, Eric N

    2007-12-26

    The mechanism of the enantioselective cyanosilylation of ketones catalyzed by tertiary amino-thiourea derivatives was investigated using a combination of experimental and theoretical methods. The kinetic analysis is consistent with a cooperative mechanism in which both the thiourea and the tertiary amine of the catalyst are involved productively in the rate-limiting cyanide addition step. Density functional theory calculations were used to distinguish between mechanisms involving thiourea activation of ketone or of cyanide in the enantioselectivity-determining step. The strong correlation obtained between experimental and calculated ee's for a range of substrates and catalysts provides support for the most favorable calculated transition structures involving amine-bound HCN adding to thiourea-bound ketone. The calculations suggest that enantioselectivity arises from direct interactions between the ketone substrate and the amino-acid derived portion of the catalyst. On the basis of this insight, more enantioselective catalysts with broader substrate scope were prepared and evaluated experimentally.

  18. Cornell University Libraries. A Final Report from the Public Services Research Projects. Appropriate Public Services for Agricultural Research Faculty. One of a Series of Self-Studies and Research Projects.

    ERIC Educational Resources Information Center

    Olsen, Jan Kennedy; And Others

    This paper reports a self-study undertaken at Cornell University's Albert R. Mann Library to explore appropriate public services for an agricultural research faculty. The study took place over a 22-month period and involved a literature review, development of a questionnaire, administration of the questionnaire, an experimental period of…

  19. Adventitious root formation in tree species: involvement of transcription factors.

    PubMed

    Legué, Valérie; Rigal, Adeline; Bhalerao, Rishikesh P

    2014-06-01

    Adventitious rooting is an essential step in the vegetative propagation of economically important horticultural and woody species. Populus has emerged as an experimental model for studying processes that are important in tree growth and development. It is highly useful for molecular genetic analysis of adventitious roots in trees. In this short review, we will highlight the recent progress made in the identification of transcription factors involved in the control of adventitious rooting in woody species. Their regulation will be discussed. © 2014 Scandinavian Plant Physiology Society.

  20. Fourth National Aeronautics and Space Administration Weather and Climate Program Science Review

    NASA Technical Reports Server (NTRS)

    Kreins, E. R. (Editor)

    1979-01-01

    The NASA Weather and Climate Program has two major thrusts. The first involves the development of experimental and prototype operational satellite systems, sensors, and space facilities for monitoring and understanding the atmosphere. The second thrust involves basic scientific investigation aimed at studying the physical and chemical processes which control weather and climate. This fourth science review concentrated on the scientific research rather than the hardware development aspect of the program. These proceedings contain 65 papers covering the three general areas: severe storms and local weather research, global weather, and climate.

  1. The role of partitioning of reagents in grafting and curing reactions initiated by ionizing radiation and UV

    NASA Astrophysics Data System (ADS)

    Chaplin, R. P.; Dworjanyn, P. A.; Gamage, N. J. W.; Garnett, J. L.; Jankiewicz, S. V.; Khan, M. A.; Sangster, D. F.

    1996-03-01

    Experimental evidence involving monomer absorption studies using tritiated styrene is shown to support the proposal that additives such as mineral acids and certain inorganic salts when dissolved in the monomer solution enhance radiation grafting yields by a mechanism involving partitioning of reagents. Photoinitiators such as benzoin ethyl ether and its methyl analogue are reported as new additives for grafting of styrene in methanol to cellulose and polypropylene initiated by ionizing radiation. The partitioning concept is shown to be relevant in analogous UV grafting and curing processes.

  2. A meta-analysis of experimental studies of diversion programs for juvenile offenders.

    PubMed

    Schwalbe, Craig S; Gearing, Robin E; MacKenzie, Michael J; Brewer, Kathryne B; Ibrahim, Rawan

    2012-02-01

    Research to establish an evidence-base for the treatment of conduct problems and delinquency in adolescence is well established; however, an evidence-base for interventions with offenders who are diverted from the juvenile justice system has yet to be synthesized. The purpose of this study was to conduct a meta-analysis of experimental studies testing juvenile diversion programs and to examine the moderating effect of program type and implementation quality. A literature search using PsycINFO, Web of Science, and the National Criminal Justice Reference Service data-bases and research institute websites yielded 28 eligible studies involving 57 experimental comparisons and 19,301 youths. Recidivism was the most common outcome reported across all studies. Overall, the effect of diversion programs on recidivism was non-significant (k=45, OR=0.83, 95%CI=0.43-1.58). Of the five program types identified, including case management (k=18, OR=0.78), individual treatment (k=11, OR=0.83), family treatment (k=4, OR=0.57), youth court (k=6, OR=0.93), and restorative justice (k=6, OR=0.87), only family treatment led to a statistically significant reduction in recidivism. Restorative justice studies that were implemented with active involvement of researchers led to statistically significant reductions in recidivism (k=3, OR=0.69). Other outcomes, including frequency of offending, truancy, and psycho-social problems were reported infrequently and were not subjected to meta-analysis. High levels of heterogeneity characterize diversion research. Results of this study recommend against implementation of programs limited to case management and highlight the promise of family interventions and restorative justice. Copyright © 2011 Elsevier Ltd. All rights reserved.

  3. Transcriptional Profiling of Midguts Prepared from Trypanosoma/T. congolense-Positive Glossina palpalis palpalis Collected from Two Distinct Cameroonian Foci: Coordinated Signatures of the Midguts’ Remodeling As T. congolense-Supportive Niches

    PubMed Central

    Tsagmo Ngoune, Jean M.; Njiokou, Flobert; Loriod, Béatrice; Kame-Ngasse, Ginette; Fernandez-Nunez, Nicolas; Rioualen, Claire; van Helden, Jacques; Geiger, Anne

    2017-01-01

    Our previous transcriptomic analysis of Glossina palpalis gambiensis experimentally infected or not with Trypanosoma brucei gambiense aimed to detect differentially expressed genes (DEGs) associated with infection. Specifically, we selected candidate genes governing tsetse fly vector competence that could be used in the context of an anti-vector strategy, to control human and/or animal trypanosomiasis. The present study aimed to verify whether gene expression in field tsetse flies (G. p. palpalis) is modified in response to natural infection by trypanosomes (T. congolense), as reported when insectary-raised flies (G. p. gambiensis) are experimentally infected with T. b. gambiense. This was achieved using the RNA-seq approach, which identified 524 DEGs in infected vs. non-infected tsetse flies, including 285 downregulated genes and 239 upregulated genes (identified using DESeq2). Several of these genes were highly differentially expressed, with log2 fold change values in the vicinity of either +40 or −40. Downregulated genes were primarily involved in transcription/translation processes, whereas encoded upregulated genes governed amino acid and nucleotide biosynthesis pathways. The BioCyc metabolic pathways associated with infection also revealed that downregulated genes were mainly involved in fly immunity processes. Importantly, our study demonstrates that data on the molecular cross-talk between the host and the parasite (as well as the always present fly microbiome) recorded from an experimental biological model has a counterpart in field flies, which in turn validates the use of experimental host/parasite couples. PMID:28804485

  4. Compelled body weight shift approach in rehabilitation of individuals with chronic stroke.

    PubMed

    Aruin, Alexander S; Rao, Noel; Sharma, Asha; Chaudhuri, Gouri

    2012-01-01

    This study was designed to evaluate the effectiveness of the compelled body weight shift (CBWS) therapy approach in the rehabilitation of individuals with chronic stroke. CBWS involves a forced shift of body weight toward a person's affected side by means of a shoe insert that establishes a lift of the nonaffected lower extremity. Eighteen individuals with chronic, unilateral stroke (mean age 57.7 ± 11.9 years, with a range of 35-75 years; mean time since stroke 6.7 ± 3.9 years, with a range of 1.1-14.1 years) who showed asymmetrical stance were randomly divided into 2 groups: the experimental group received 6 weeks of physical therapy combined with CBWS therapy, and the control group received only physical therapy. Both groups underwent a battery of identical tests (Fugl-Meyer Assessment, Berg Balance Scale, weight bearing, and gait velocity) before the start of the rehabilitation intervention, following its completion, and 3 months after the end of therapy. After the intervention, weight bearing on the affected side (measured with the Balance Master) increased in the experimental group to a larger degree compared to the control group (9.7% vs 6.4%). Similarly, gait velocity increased 10.5% in the experimental group compared to the control group. Improvements in weight bearing and gait velocity were maintained in the experimental group after the 3-month retention period. The study outcome revealed that a 6-week intervention involving CBWS therapy could result in a long-lasting improvement of the symmetry of weight bearing and velocity of gait in individuals with chronic stroke.

  5. Computational investigation of kinetics of cross-linking reactions in proteins: importance in structure prediction.

    PubMed

    Bandyopadhyay, Pradipta; Kuntz, Irwin D

    2009-01-01

    The determination of protein structure using distance constraints is a new and promising field of study. One implementation involves attaching residues of a protein using a cross-linking agent, followed by protease digestion, analysis of the resulting peptides by mass spectroscopy, and finally sequence threading to detect the protein folds. In the present work, we carry out computational modeling of the kinetics of cross-linking reactions in proteins using the master equation approach. The rate constants of the cross-linking reactions are estimated using the pKas and the solvent-accessible surface areas of the residues involved. This model is tested with fibroblast growth factor (FGF) and cytochrome C. It is consistent with the initial experimental rate data for individual lysine residues for cytochrome C. Our model captures all observed cross-links for FGF and almost 90% of the observed cross-links for cytochrome C, although it also predicts cross-links that were not observed experimentally (false positives). However, the analysis of the false positive results is complicated by the fact that experimental detection of cross-links can be difficult and may depend on specific experimental conditions such as pH, ionic strength. Receiver operator characteristic plots showed that our model does a good job in predicting the observed cross-links. Molecular dynamics simulations showed that for cytochrome C, in general, the two lysines come closer for the observed cross-links as compared to the false positive ones. For FGF, no such clear pattern exists. The kinetic model and MD simulation can be used to study proposed cross-linking protocols.

  6. Effects of Childhood Gymnastics Program on Spatial Working Memory.

    PubMed

    Hsieh, Shu-Shih; Lin, Chih-Chien; Chang, Yu-Kai; Huang, Chung-Ju; Hung, Tsung-Min

    2017-12-01

    A growing body of evidence has demonstrated the positive effects of physical exercise on cognition in children, and recent studies have specifically investigated the cognitive benefits of exercises involving cognitive-motor interactions, such as gymnastics. This study examined the effect of 8 wk of gymnastics training on behavioral and neurophysiological measures of spatial working memory in children. Forty-four children age 7 to 10 yr were recruited. The experimental group (n = 24; age, 8.7 ± 1.1 yr) was recruited from Yilan County in Taiwan, while the control group (n = 20; age, 8.6 ± 1.1 yr) resided in Taipei City. The experimental group undertook 8 wk of after-school gymnastics training (2 sessions per week, 90 min per session), whereas the control group received no intervention and were instructed to maintain their routine daily activities. Working memory was assessed by performance on a modified delayed match-to-sample test and by event-related potential including the P3 component. Data were collected before and after treatment for the experimental group and at the same time interval for the control group. Response accuracy improved after the experimental intervention regardless of working memory demands. Likewise, the P3 amplitude was larger at the parietal site after gymnastics training regardless of the task difficulty. Our results suggest that a short period of gymnastics training had a general facilitative effect on spatial working memory at both behavioral and neurophysiological levels in children. These finding highlight the potential importance of exercise programs involving cognitive-motor interactions in stimulating development of spatial cognition during childhood.

  7. Effect of 8 days of a hypergravity condition on the sprinting speed and lower-body power of elite rugby players.

    PubMed

    Barr, Matthew J; Gabbett, Tim J; Newton, Robert U; Sheppard, Jeremy M

    2015-03-01

    -Sprinting speed and lower-body power are considered to be key physical abilities for rugby players. A method of improving the lower-body power of athletes is simulated hypergravity. This method involves wearing a weighted vest at all times during the day for an extended period of time. There are no studies that have examined the effect of hypergravity on speed or the benefit for rugby players. An experimental group (n = 8) and a control group (n = 7) of national team rugby players took part in the study, which consisted of rugby, conditioning, speed, and strength sessions. The experimental group wore a weighted vest equating to 12% of their body mass for 8 days. All players were tested for speed and lower-body power before, 2 days after, and 9 days after the intervention. Speed testing involved the athletes completing 40-m sprints with timing lights and high-speed video cameras assessing acceleration and maximal velocity sprinting kinematics. Lower-body power was assessed using weighted countermovement jumps (CMJs). No group differences were found for sprinting speed at any point. The experimental group displayed a large decrease in acceleration ground contact time (-0.01 ± 0.005 s, d = 1.07) and a moderate increase in 15-kg CMJ velocity (0.07 ± 0.11 m·s, d = 0.71). Individual responses showed that players in the experimental group had both negative and positive speed and power responses to the training intervention. Simulated hypergravity for 8 days is likely ineffective at improving sprinting speed while undergoing standard rugby training.

  8. Combined experimental and ab initio study of the electronic structure of narrow-diameter single-wall carbon nanotubes with predominant (6,4),(6,5) chirality

    NASA Astrophysics Data System (ADS)

    de Blauwe, K.; Mowbray, D. J.; Miyata, Y.; Ayala, P.; Shiozawa, H.; Rubio, A.; Hoffmann, P.; Kataura, H.; Pichler, T.

    2010-09-01

    Narrow diameter tubes and especially (6,5) tubes with a diameter of 0.75 nm are currently one of the most studied carbon nanotubes because their unique optical and especially luminescence response makes them exceptionally suited for biomedical applications. Here we report on a detailed analysis of the electronic structure of nanotubes with (6,5) and (6,4) chiralities using a combined experimental and theoretical approach. From high-energy spectroscopy involving x-ray absorption and photoemission spectroscopy the detailed valence- and conduction-band response of these narrow diameter tubes is studied. The observed electronic structure is in sound agreement with state of the art ab initio calculations using density-functional theory.

  9. The Use Of High Speed Photography In Reactor Safety Studies At The Atomic Energy Establishment, Winfrith

    NASA Astrophysics Data System (ADS)

    Maddison, R. J.

    1985-02-01

    The investigation of certain areas of nuclear reactor safety involves the study of high speed phenomena with timescales ranging from microseconds to a few hundreds of milliseconds. Examples which have been extensively studied at Winfrith are firstly, the thermal interaction of molten fuel and reactor coolant which can generate high pressures on the 100 msec timescale, and which involves phenomena such as vapour film collapse which takes place on the microsecond timescale. Secondly, there is the response of reactor structures to such pressures, and finally there is the response of structural materials such as metals and concrete to the impulsive loading arising from the impact of heavy, high velocity missiles. A wide range of experimental techniques is used in these studies, many of which have been developed specially for this type of work which ranges from small laboratory scale to large field scale experiments. There are two important features which characterise many of these experiments:- i) a long period of meticulous preparation of very heavily instrumented, short duration experiments and; ii) the destructive nature of the experiments. Various forms of High Speed photography are included in the inventory of experimental techniques. These include the use of single and double exposure, short duration, spark photography; the use of an Image Convertor Camera (IMACON 790); and a number of rotating prism cine cameras. High Speed Photography is used both in a primary experimental role in the studies, and in a supportive role for other instrumentation. Because of the sometimes violent nature of these experiments, cameras are often heavily protected and operated remotely; lighting systems are sometimes destroyed. This has led to the development of unconventional techniques for camera operation and subject lighting. This paper will describe some of the experiments and the way in which High Speed Photography has been applied as an essential experimental tool. It will be illustrated with cine film taken during the experiments.

  10. Supporting Scientific Experimentation and Reasoning in Young Elementary School Students

    ERIC Educational Resources Information Center

    Varma, Keisha

    2014-01-01

    Researchers from multiple perspectives have shown that young students can engage in the scientific reasoning involved in science experimentation. However, there is little research on how well these young students learn in inquiry-based learning environments that focus on using scientific experimentation strategies to learn new scientific…

  11. 75 FR 1772 - Pesticide Experimental Use Permits; Receipt of Applications; Comment Requests

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-01-13

    ... ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-OPP-2009-0615; FRL-8433-2] Pesticide Experimental Use... Pioneer Hi-Bred International, Inc. requesting experimental use permits (EUPs) for seed blends of the... meaningful involvement of any group, including minority and/or low income populations, in the development...

  12. Effects of sleeping position on back pain in physically active seniors: A controlled pilot study.

    PubMed

    Desouzart, Gustavo; Matos, Rui; Melo, Filipe; Filgueiras, Ernesto

    2015-01-01

    The increase in life expectancy of elderly population has aroused the interest of different knowledge areas in understanding the variables that are involved in the aging process, linking them to other concepts such as active aging, healthy aging and the bio-psycho-social changes. This paper presents the results of the first controlled, experimental pilot study that aimed to analyze the relationship between the perception of back pain and the sleeping position adopted by physically active female seniors. Twenty female seniors (mean age 62.70 ± 3.827) participated in this study. The individuals were separated in 2 groups (Experimental and Control Group). For the carrying out of this study, the Visual Analogue Scale (VAS) was used to measure the intensity of back pain in the spine before and after four consecutive weeks an Intervention program. Individuals in the Experimental Group were instructed regarding the recommended way to sleep position (Intervention program) according to the pathological problems or the amount of pain reported. The Experimental Group (N = 10) presented significantly (p = 0.009) fewer complaints of back pain after an Intervention program in comparison to individuals who did not receive this type of information (Control Group).

  13. Annual tendency of research papers used ICR mice as experimental animals in biomedical research fields.

    PubMed

    Kim, Ji Eun; Nam, Jung Hoon; Cho, Joon Young; Kim, Kil Soo; Hwang, Dae Youn

    2017-06-01

    Institute of Cancer Research (ICR) mice have been widely used in various research fields including toxicology, oncology, pharmacology, and pharmaceutical product safety testing for decades. However, annual tendency of research papers involving ICR mice in various biomedical fields has not been previously analyzed. In this study, we examined the numbers of papers that used ICR mice as experimental animals in the social science, natural science, engineering, medicine-pharmacy, marine agriculture-fishery, and art-kinesiology fields by analyzing big data. Numbers of ICR mouse-used papers gradually increased from 1961 to 2014, but small decreases were observed in 2015 and 2016. The largest number of ICR-used papers were published in the medicine-pharmacy field, followed by natural science and art-kinesiology fields. There were no ICR mouse-used papers in other fields. Furthermore, ICR mice have been widely employed in cell biology studies within the natural science field as well as in biochemistry and pathology in the medicine-pharmacy field. Few ICR mouse-used papers were published in exercise biochemistry and exercise nutrition in the art-kinesiology field. Regardless in most fields, the total numbers of published papers involving ICR mice were higher in 2014 than in other years, although the numbers in some fields including dentistry, veterinary science, and dermatology were high in 2016. Taken together, the present study shows that various ICR stocks, including Korl:ICR mice, are widely employed as experimental animals in various biomedical research fields.

  14. Annual tendency of research papers used ICR mice as experimental animals in biomedical research fields

    PubMed Central

    Kim, Ji Eun; Nam, Jung Hoon; Cho, Joon Young; Kim, Kil Soo

    2017-01-01

    Institute of Cancer Research (ICR) mice have been widely used in various research fields including toxicology, oncology, pharmacology, and pharmaceutical product safety testing for decades. However, annual tendency of research papers involving ICR mice in various biomedical fields has not been previously analyzed. In this study, we examined the numbers of papers that used ICR mice as experimental animals in the social science, natural science, engineering, medicine-pharmacy, marine agriculture-fishery, and art-kinesiology fields by analyzing big data. Numbers of ICR mouse-used papers gradually increased from 1961 to 2014, but small decreases were observed in 2015 and 2016. The largest number of ICR-used papers were published in the medicine-pharmacy field, followed by natural science and art-kinesiology fields. There were no ICR mouse-used papers in other fields. Furthermore, ICR mice have been widely employed in cell biology studies within the natural science field as well as in biochemistry and pathology in the medicine-pharmacy field. Few ICR mouse-used papers were published in exercise biochemistry and exercise nutrition in the art-kinesiology field. Regardless in most fields, the total numbers of published papers involving ICR mice were higher in 2014 than in other years, although the numbers in some fields including dentistry, veterinary science, and dermatology were high in 2016. Taken together, the present study shows that various ICR stocks, including Korl:ICR mice, are widely employed as experimental animals in various biomedical research fields. PMID:28747984

  15. Experimental gravitation in space - Is there a future?

    NASA Astrophysics Data System (ADS)

    Wharton, R. A.; McKay, C. P.; Mancinelli, R. L.; Simmons, G. M.

    Experimental gravitation enters the 1990s with a past full of successes, but with a future full of uncertainties. Intellectually, the field is as vigorous as ever, with major thrusts in three main areas: the search for gravitational radiation, the study of post and post-post Newtonian effects, and the detection of hypothetical feeble new interactions. It is the only branch of space research involved in fundamental physics. But politically and financially, the future is uncertain. Competition for funding and for flight opportunities will be stiff for the foreseeable future, both with other disciplines such as astrophysics, planetary science and the military, and within experimental gravitation itself. Difficult choices lie ahead. This paper reviews the current state of the field and attempts to peer into the future.

  16. Prevention of hepatocellular carcinoma: potential targets, experimental models, and clinical challenges

    PubMed Central

    Hoshida, Yujin; Fuchs, Bryan C.; Tanabe, Kenneth K.

    2013-01-01

    Chronic fibrotic liver diseases such as viral hepatitis eventually develop liver cirrhosis, which causes occurrence of hepatocellular carcinoma (HCC). Given the limited therapeutic efficacy in advanced HCC, prevention of HCC development could be an effective strategy for improving patient prognosis. However, there is still no established therapy to meet the goal. Studies have elucidated a wide variety of molecular mechanisms and signaling pathways involved in HCC development. Genetically-engineered or chemically-treated experimental models of cirrhosis and HCC have been developed and shown their potential value in investigating molecular therapeutic targets and diagnostic biomarkers for HCC prevention. In this review, we overview potential targets of prevention and currently available experimental models, and discuss strategies to translate the findings into clinical practice. PMID:22873223

  17. Are decisions under risk malleable?

    PubMed

    Fong, C; McCabe, K

    1999-09-14

    Human decision making under risk and uncertainty may depend on individual involvement in the outcome-generating process. Expected utility theory is silent on this issue. Prospect theory in its current form offers little, if any, prediction of how or why involvement in a process should matter, although it may offer ex post interpretations of empirical findings. Well-known findings in psychology demonstrate that when subjects exercise more involvement or choice in lottery procedures, they value their lottery tickets more highly. This often is interpreted as an "illusion of control," meaning that when subjects are more involved in a lottery, they may believe they are more likely to win, perhaps because they perceive that they have more control over the outcome. Our experimental design eliminates several possible alternative explanations for the results of previous studies in an experiment that varies the degree and type of involvement in lottery procedures. We find that in treatments with more involvement subjects on average place less rather than more value on their lottery tickets. One possible explanation for this is that involvement interacts with loss aversion by causing subjects to weigh losses more heavily than they would otherwise. One implication of our study is that involvement, either independently or in interaction with myopic loss aversion, may help explain the extreme risk aversion of bond investors.

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

    ERIC Educational Resources Information Center

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

    2015-01-01

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

  19. The Effect of Implementing the Experiential Learning Model in Listening Comprehension for the Eleventh Graders at SMAN 1 Telaga Biru

    ERIC Educational Resources Information Center

    Tahir, Ismail

    2017-01-01

    This study is aimed to investigate the effectiveness of the experiential learning in listening comprehension with the focus on the implementation of the class story using language experience at SMAN 1 Telaga Biru. As the pre-experimental research, this study involved one class consisted of 27 students in the eleventh graders. However, most of the…

  20. Effect of the Blended Learning Environment and the Application of Virtual Class upon the Achievement and the Attitude against the Geography Course

    ERIC Educational Resources Information Center

    Dikmenli, Yurdal; Unaldi, Ulku Eser

    2013-01-01

    This study involves the elucidation of the effect of the virtual classroom application and blended learning medium upon the academic achievement of the students and their attitudes against the geography curse compared to the face to face expository (traditional) method. The study was carried out according to pre-test--post-test experimental design…

  1. Preliminary Study of Applied Load Factors in Bumpy Air

    NASA Technical Reports Server (NTRS)

    Rhode, Richard V; Lundquist, Eugene E

    1931-01-01

    Theoretical relations involved in the study are reviewed to furnish a basis upon which experimental data can be properly analyzed. The structure of the atmosphere in relation to the load-factor problem is briefly discussed, and the acceleration data obtained on a number of flights with various airplanes are presented and analyzed to the extent that the results are applicable to n=any airplane.

  2. Direct Teaching of Vocabulary after Listening: Is It Worth the Effort and What Method is Best?

    ERIC Educational Resources Information Center

    Hennebry, Mairin; Rogers, Vivienne; Macaro, Ernesto; Murphy, Victoria

    2017-01-01

    This paper reports a study comparing the effects of vocabulary instruction on recognition and recall through provision of either an L1 equivalent or an L2 (French) definition. Instruction was in the context of a focus-on-meaning listening activity. The study employed a quasi-experimental design, involving 262 Year 9 learners of French in seven…

  3. What Differentiates Adolescent Problematic Drinkers from Their Peers? Results from a Cross-Sectional Study in Northern Irish School Children

    ERIC Educational Resources Information Center

    McKay, Michael T.; Sumnall, Harry; Goudie, Andrew J.; Field, Matt; Cole, Jon C.

    2011-01-01

    Aim: To investigate whether or not a range of factors were associated with problematic drinking, as assessed using the Adolescent Alcohol Involvement Scale (AAIS) in a sample of 11-16-year olds in Northern Ireland. Methods: The study used a cross-sectional experimental design. Post-primary schools in the Eastern Health Board Area of Northern…

  4. The Social Science Teacher; Vol. 4, No. 1, Summer 1974.

    ERIC Educational Resources Information Center

    Townley, Charles, Ed.

    This new British journal is a medium of communication for those involved in teaching social science and social studies at the secondary and elementary levels. The first article in this issue, Ian Shelton's "The Sociology of Everyday Life," describes an experimental short course in secondary sociology. The course is designed to produce an…

  5. Parent-Child Parallel-Group Intervention for Childhood Aggression in Hong Kong

    ERIC Educational Resources Information Center

    Fung, Annis L. C.; Tsang, Sandra H. K. M.

    2006-01-01

    This article reports the original evidence-based outcome study on parent-child parallel group-designed Anger Coping Training (ACT) program for children aged 8-10 with reactive aggression and their parents in Hong Kong. This research program involved experimental and control groups with pre- and post-comparison. Quantitative data collection…

  6. Developing Prosocial Behaviors in Early Adolescence with Reactive Aggression

    ERIC Educational Resources Information Center

    Fung, Annis L. C.

    2008-01-01

    Despite the alarming rise of early adolescence aggression in Hong Kong, it is the pioneer evidence-based outcome study on Anger Coping Training (ACT) program for early adolescence with reactive aggression to develop their prosocial behaviors. This research program involved experimental and control groups with pre- and post-comparison using a …

  7. Gaming via Computer Simulation Techniques for Junior College Economics Education. Final Report.

    ERIC Educational Resources Information Center

    Thompson, Fred A.

    A study designed to answer the need for more attractive and effective economics education involved the teaching of one junior college economics class by the conventional (lecture) method and an experimental class by computer simulation techniques. Econometric models approximating the "real world" were computer programed to enable the experimental…

  8. Enhancing Eight Grade Students' Scientific Conceptual Change and Scientific Reasoning through a Web-Based Learning Program

    ERIC Educational Resources Information Center

    Liao, Ya-Wen; She, Hsiao-Ching

    2009-01-01

    This study reports the impacts of the Scientific Concept Construction and Reconstruction (SCCR) digital learning system on eighth grade students' concept construction, conceptual change, and scientific reasoning involving the topic of "atoms". A two-factorial experimental design was carried out to investigate the effects of the approach…

  9. Measuring Thermal Variations in a Valley Environment Using a Team, Field Project Designed by Students

    ERIC Educational Resources Information Center

    Abbott, J. Anthony

    2006-01-01

    Students frequently struggle when scientific instruction seems divorced from personal experience, especially in the physical sub-disciplines, like climatology, where exercise books often present historical or abstracted case studies. In contrast I present a three-phase project involving student input on experimental design, data collection, and…

  10. Reflective Learning and Prospective Teachers' Conceptual Understanding, Critical Thinking, Problem Solving, and Mathematical Communication Skills

    ERIC Educational Resources Information Center

    Junsay, Merle L.

    2016-01-01

    This is a quasi-experimental study that explored the effects of reflective learning on prospective teachers' conceptual understanding, critical thinking, problem solving, and mathematical communication skills and the relationship of these variables. It involved 60 prospective teachers from two basic mathematics classes of an institution of higher…

  11. Why Traditional Expository Teaching-Learning Approaches May Founder? An Experimental Examination of Neural Networks in Biology Learning

    ERIC Educational Resources Information Center

    Lee, Jun-Ki; Kwon, Yong-Ju

    2011-01-01

    Using functional magnetic resonance imaging (fMRI), this study investigates and discusses neurological explanations for, and the educational implications of, the neural network activations involved in hypothesis-generating and hypothesis-understanding for biology education. Two sets of task paradigms about biological phenomena were designed:…

  12. Colour and Light Effects on Students' Achievement, Behavior and Physiology.

    ERIC Educational Resources Information Center

    Wohlfarth, H.

    A quasi-experimental non-equivalent control group design was used to investigate the effects of full-spectrum light, prescribed color and light/color combinations, ultra-violet light, and electromagnetic radiation in an elementary school environment. Four schools in the Wetaskiwin School District, Alberta, were involved in the study; three served…

  13. The Effect of Contextual and Conceptual Rewording on Mathematical Problem-Solving Performance

    ERIC Educational Resources Information Center

    Haghverdi, Majid; Wiest, Lynda R.

    2016-01-01

    This study shows how separate and combined contextual and conceptual problem rewording can positively influence student performance in solving mathematical word problems. Participants included 80 seventh-grade Iranian students randomly assigned in groups of 20 to three experimental groups involving three types of rewording and a control group. All…

  14. Comparative Effects of Ability and Feedback Form in Computer-Assisted Instruction.

    ERIC Educational Resources Information Center

    Clariana, Roy B.; Smith, Lana J.

    A study involving 50 experimental and 99 control subjects (graduate education majors) was undertaken to assess the interchangeability of knowledge of correct response feedback (KRC) and answer until correct feedback (AUC) in computer-assisted instruction. P. L. Smith's model (1988) suggests that AUC in better for high-ability students. W. Dick and…

  15. A Naturalistic Alcohol Availability Experiment: Effects on Crime.

    ERIC Educational Resources Information Center

    Kraushaar, Kevin; Alsop, Brent

    Previous investigators have looked at many types of criminal offenses in order to determine alcohol involvement in crime. This longitudinal (4-year) naturalistic experimental and control designed study examined the effects of change in alcohol availability on rates of offending in a small provincial region of New Zealand following the closure of…

  16. The Impact of Recurrent On-Line Synchronous Scientific Argumentation on Students' Argumentation and Conceptual Change

    ERIC Educational Resources Information Center

    Chen, Chien-Hsien; She, Hsiao-Ching

    2012-01-01

    This study reports the impact of Recurrent On-Line Synchronous Scientific Argumentation learning on 8th grade students' scientific argumentation ability and conceptual change involving physical science. The control group (N = 76) were recruited to receive conventional instruction whereas the experimental group (N = 74) received the Recurrent…

  17. Triple Scheme of Learning Support Design for Scientific Discovery Learning Based on Computer Simulation: Experimental Research

    ERIC Educational Resources Information Center

    Zhang, Jianwei; Chen, Qi; Sun, Yanquing; Reid, David J.

    2004-01-01

    Learning support studies involving simulation-based scientific discovery learning have tended to adopt an ad hoc strategies-oriented approach in which the support strategies are typically pre-specified according to learners' difficulties in particular activities. This article proposes a more integrated approach, a triple scheme for learning…

  18. Chimpanzees Know What Others Know, but Not What They Believe

    ERIC Educational Resources Information Center

    Kaminski, Juliane; Call, Josep; Tomasello, Michael

    2008-01-01

    There is currently much controversy about which, if any, mental states chimpanzees and other nonhuman primates understand. In the current two studies we tested both chimpanzees' and human children's understanding of both knowledge-ignorance and false belief--in the same experimental paradigm involving competition with a conspecific. We found that…

  19. A Heuristic Approach to the Lens Equation

    ERIC Educational Resources Information Center

    Whitaker, Robert J.

    2011-01-01

    An experimental approach to obtaining the reciprocal relationships involved in a study of lenses is introduced. Through an analysis of the data obtained for the combination of two lenses of different focal lengths one finds a formula for the combination in terms of the data for individual lenses by arguing by analogy. This procedure then suggests…

  20. The Effects of a Course in Science and Culture Designed for Secondary School Students.

    ERIC Educational Resources Information Center

    Cossman, George Wilford

    This study was designed to evaluate the success of an experimental secondary school course for fostering scientific literacy and the development of scientific attitudes. Students were matched using I.Q., sex, grade level, involvement with formal science courses, and cumulative grade point average. Twenty-one "self selected" eleventh and…

  1. Dynamic Nature of Atoms and Molecules, Science (Experimental): 5316.06.

    ERIC Educational Resources Information Center

    Buffaloe, Jacquelin F.

    This unit of instruction deals with the study of both physical and chemical systems in equilibrium. It provides the student with instruction that will enable him to predict products in solubility, acid-base, and oxidation-reduction reactions and to write and balance equations for these reactions and solve problems involving equilibria constants.…

  2. An Experimental Study of Interference between Receptive and Productive Processes Involving Speech

    ERIC Educational Resources Information Center

    Goldman-Eisler, Frieda; Cohen, Michele

    1975-01-01

    Reports an experiment designed to throw light on the interference between the reception and production of speech by controlling the level of interference between decoding and encoding, using hesitancy as an indicator of interference. This proved effective in spotting the levels at which interference takes place. (Author/RM)

  3. Investigation of Unexpected Reaction Intermediates in the Alkaline Hydrolysis of Methyl 3,5-Dinitrobenzoate

    ERIC Educational Resources Information Center

    Silva, Clesia C.; Silva, Ricardo O.; Navarro, Daniela M. A. F.; Navarro, Marcelo

    2009-01-01

    An experimental project aimed at identifying stable reaction intermediates is described. Initially, the studied reaction appears to involve the simple hydrolysis, by aqueous sodium hydroxide, of methyl 3,5-dinitrobenzoate dissolved in dimethyl sulfoxide. On mixing the substrates, however, the reaction mixture unexpectedly turns an intense red in…

  4. Evaluating the Impact of Two Globalization Projects on College Students' Cultural Competence and Cultural Intelligence (CQ)

    ERIC Educational Resources Information Center

    Lopes-Murphy, Solange A.

    2013-01-01

    Cultural competence and CQ involve awareness of cultural similarities and differences, knowledge of differences in cultural values, and intercultural encounters. To assess college students' cultural competence and cultural intelligence gains, this experimental study evaluated the impact of two globalization projects on these two constructs. The…

  5. Follow Through Classroom Process Measurement and Pupil Growth (1970-71). Final Report.

    ERIC Educational Resources Information Center

    Soar, Robert S.

    This study presents results from the last year of a three-year adjunctive evaluation of classroom process measurement and pupil growth. A total of 289 classrooms involving eight experimental programs, ranging from open classrooms to contingency management classes, along with a comparison sample, were observed. Four observation instruments were…

  6. Learning Mathematics via a Problem-Centered Approach: A Two-Year Study

    ERIC Educational Resources Information Center

    Ridlon, Candice L.

    2009-01-01

    For nine-week periods during two consecutive years, sixth-grade students at the same school were taught identical mathematics content using two different instructional approaches. Year 1 involved low achievers, whereas Year 2 was mixed ability students. The experimental treatment was a problem-centered approach (PCL) where potentially meaningful…

  7. Fruits for Prevention and Treatment of Cardiovascular Diseases

    PubMed Central

    Zhao, Cai-Ning; Meng, Xiao; Li, Ya; Li, Sha; Liu, Qing; Tang, Guo-Yi; Li, Hua-Bin

    2017-01-01

    Cardiovascular diseases (CVDs) are leading global health problems. Accumulating epidemiological studies have indicated that consuming fruits was inversely related to the risk of CVDs. Moreover, substantial experimental studies have supported the protective role of fruits against CVDs, and several fruits (grape, blueberry, pomegranate, apple, hawthorn, and avocado) have been widely studied and have shown potent cardiovascular protective action. Fruits can prevent CVDs or facilitate the restoration of morphology and functions of heart and vessels after injury. The involved mechanisms included protecting vascular endothelial function, regulating lipids metabolism, modulating blood pressure, inhibiting platelets function, alleviating ischemia/reperfusion injury, suppressing thrombosis, reducing oxidative stress, and attenuating inflammation. The present review summarizes recent discoveries about the effects of fruits on CVDs and discusses potential mechanisms of actions based on evidence from epidemiological, experimental, and clinical studies. PMID:28608832

  8. Protein kinase C is involved with upstream signaling of methyl farnesoate for photoperiod-dependent sex determination in the water flea Daphnia pulex.

    PubMed

    Toyota, Kenji; Sato, Tomomi; Tatarazako, Norihisa; Iguchi, Taisen

    2017-02-15

    Sex determination of Daphnia pulex is decided by environmental conditions. We established a suitable experimental system for this study using D. pulex WTN6 strain, in which the sex of the offspring can be controlled by photoperiod. Long-day conditions induced females and short-day conditions induced males. Using this system, we previously found that methy farnesoate (MF), which is a putative innate juvenile hormone molecule in daphnids, is necessary for male sex determination and that protein kinase C (PKC) is a candidate factor of male sex determiner. In this study, we demonstrated that a PKC inhibitor [bisindolylmaleimide IV (BIM)] application strongly suppressed male offspring induction in the short-day condition. Moreover, co-treatment of BIM with MF revealed that PKC signaling acts upstream of MF signaling for male sex determination. This is the first experimental evidence that PKC is involved in the male sex determination process associated with methyl farnesoate signaling in daphnid species. © 2017. Published by The Company of Biologists Ltd.

  9. Coordinated photomorphogenic UV-B signaling network captured by mathematical modeling.

    PubMed

    Ouyang, Xinhao; Huang, Xi; Jin, Xiao; Chen, Zheng; Yang, Panyu; Ge, Hao; Li, Shigui; Deng, Xing Wang

    2014-08-05

    Long-wavelength and low-fluence UV-B light is an informational signal known to induce photomorphogenic development in plants. Using the model plant Arabidopsis thaliana, a variety of factors involved in UV-B-specific signaling have been experimentally characterized over the past decade, including the UV-B light receptor UV resistance locus 8; the positive regulators constitutive photomorphogenesis 1 and elongated hypocotyl 5; and the negative regulators cullin4, repressor of UV-B photomorphogenesis 1 (RUP1), and RUP2. Individual genetic and molecular studies have revealed that these proteins function in either positive or negative regulatory capacities for the sufficient and balanced transduction of photomorphogenic UV-B signal. Less is known, however, regarding how these signaling events are systematically linked. In our study, we use a systems biology approach to investigate the dynamic behaviors and correlations of multiple signaling components involved in Arabidopsis UV-B-induced photomorphogenesis. We define a mathematical representation of photomorphogenic UV-B signaling at a temporal scale. Supplemented with experimental validation, our computational modeling demonstrates the functional interaction that occurs among different protein complexes in early and prolonged response to photomorphogenic UV-B.

  10. Analysis of Heavy Ion Irradiation Induced Thermal Damage in SiC Schottky Diodes

    NASA Astrophysics Data System (ADS)

    Abbate, C.; Busatto, G.; Cova, P.; Delmonte, N.; Giuliani, F.; Iannuzzo, F.; Sanseverino, A.; Velardi, F.

    2015-02-01

    A study is presented aimed at describing phenomena involved in Single Event Burnout induced by heavy ion irradiation in SiC Schottky diodes. On the basis of experimental data obtained for 79Br irradiation at different energies, electro-thermal FEM is used to demonstrate that the failure is caused by a strong local increase of the semiconductor temperature. With respect to previous studies the temperature dependent thermal material properties were added. The critical ion energy calculated by this model is in agreement with literature experimental results. The substrate doping dependence of the SEE robustness was analyzed, proving the effectiveness of the developed model for device technological improvements.

  11. Mobile Genetic Elements: In Silico, In Vitro, In Vivo

    PubMed Central

    Arkhipova, Irina R.; Rice, Phoebe A.

    2016-01-01

    Mobile genetic elements (MGEs), also called transposable elements (TEs), represent universal components of most genomes and are intimately involved in nearly all aspects of genome organization, function, and evolution. However, there is currently a gap between fast-paced TE discovery in silico, stimulated by exponential growth of comparative genomic studies, and a limited number of experimental models amenable to more traditional in vitro and in vivo studies of structural, mechanistic, and regulatory properties of diverse MGEs. Experimental and computational scientists came together to bridge this gap at a recent conference, “Mobile Genetic Elements: in silico, in vitro, in vivo,” held at the Marine Biological Laboratory (MBL) in Woods Hole, MA, USA. PMID:26822117

  12. BACS: The Brussels Artificial Character Sets for studies in cognitive psychology and neuroscience.

    PubMed

    Vidal, Camille; Content, Alain; Chetail, Fabienne

    2017-12-01

    Written symbols such as letters have been used extensively in cognitive psychology, whether to understand their contributions to written word recognition or to examine the processes involved in other mental functions. Sometimes, however, researchers want to manipulate letters while removing their associated characteristics. A powerful solution to do so is to use new characters, devised to be highly similar to letters, but without the associated sound or name. Given the growing use of artificial characters in experimental paradigms, the aim of the present study was to make available the Brussels Artificial Character Sets (BACS): two full, strictly controlled, and portable sets of artificial characters for a broad range of experimental situations.

  13. An experimental study of steam explosions involving chemically reactive metal

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

    Cho, D.H.; Armstrong, D.R.; Gunther, W.H.

    1997-07-01

    An experimental study of molten zirconium-water explosions was conducted. A 1-kg mass of zirconium melt was dropped into a column of water. Explosions took place only when an external trigger was used. In the triggered tests, the extent of oxidation of the zirconium melt was very extensive. However, the explosion energetics estimated were found to be very small compared to the potential chemical energy available from the oxidation reaction. Zirconium is of particular interest, since it is a component of the core materials of the current nuclear power reactors. This paper describes the test apparatus and summarizes the results ofmore » four tests conducted using pure zirconium melt.« less

  14. An Experimental Introduction to Acoustics

    NASA Astrophysics Data System (ADS)

    Black, Andy Nicholas; Magruder, Robert H.

    2017-11-01

    Learning and understanding physics requires more than studying physics texts. It requires doing physics. Doing research is a key opportunity for students to connect physical principles with their everyday experience. A powerful way to introduce students to research and technique is through subjects in which they might find interest. Presented is an experiment that serves to introduce an advanced undergraduate or high school student to conducting research in acoustics via an experiment involving a standard dreadnought acoustic guitar, recording industry-related equipment, and relevant industrial analysis software. This experimental process is applicable to a wide range of acoustical topics including both acoustic and electric instruments. Also, the student has a hands-on experience with relevant audio engineering technology to study physical principles.

  15. Evaluation of high temperature superconductive thermal bridges for space-borne cryogenic infrared detectors

    NASA Technical Reports Server (NTRS)

    Scott, Elaine P.

    1993-01-01

    The focus of this research is on the reduction of the refrigeration requirements for infrared sensors operating in space through the use of high temperature superconductive (HTS) materials as electronic leads between the cooled sensors and the relatively warmer data acquisition components. Specifically, this initial study was directed towards the design of an experiment to quantify the thermal performance of these materials in the space environment. First, an intensive review of relevant literature was undertaken, and then, design requirements were formulated. From this background information, a preliminary experimental design was developed. Additional studies will involve a thermal analysis of the experiment and further modifications of the experimental design.

  16. The spatial evolution of energetic electrons and plasma waves during the steady state beam plasma discharge

    NASA Technical Reports Server (NTRS)

    Llobet, X.; Bernstein, W.; Kondradi, A.

    1985-01-01

    Experiments, involving the injection of energetic (keV) electron beams into the ionosphere-upper atmosphere system from rocket-borne electron guns, have provided evidence for the occurrence of strong beam-plasma interactions (BPI) both near to and remote from the injection point. However, the flight experiments have not provided clear and unambiguous evidence for the basic physical processes which produce the variety of confusing signatures. A laboratory experimental program was initiated to clarify some of a number of ambiguities regarding the obtained results. The present investigation is concerned with some experimental studies of the evolution of both the beam energy spectrum and the local wave amplitude-frequency spectrum at increasing axial distances from the electron gun for a variety of experimental conditions. The results of the studies show that the high frequency beam-plasma interaction represents the most important process.

  17. Experimental and Theoretical Study of Propeller Spinner/Shank Interference. M.S. Thesis

    NASA Technical Reports Server (NTRS)

    Cornell, C. C.

    1986-01-01

    A fundamental experimental and theoretical investigation into the aerodynamic interference associated with propeller spinner and shank regions was conducted. The research program involved a theoretical assessment of solutions previously proposed, followed by a systematic experimental study to supplement the existing data base. As a result, a refined computational procedure was established for prediction of interference effects in terms of interference drag and resolved into propeller thrust and torque components. These quantities were examined with attention to engineering parameters such as two spinner finess ratios, three blade shank forms, and two/three/four/six/eight blades. Consideration of the physics of the phenomena aided in the logical deduction of two individual interference quantities (cascade effects and spinner/shank juncture interference). These interference effects were semi-empirically modeled using existing theories and placed into a compatible form with an existing propeller performance scheme which provided the basis for examples of application.

  18. Investigation of the Thermomechanical Response of Shape Memory Alloy Hybrid Composite Beams

    NASA Technical Reports Server (NTRS)

    Davis, Brian A.

    2005-01-01

    Previous work at NASA Langley Research Center (LaRC) involved fabrication and testing of composite beams with embedded, pre-strained shape memory alloy (SMA) ribbons. That study also provided comparison of experimental results with numerical predictions from a research code making use of a new thermoelastic model for shape memory alloy hybrid composite (SMAHC) structures. The previous work showed qualitative validation of the numerical model. However, deficiencies in the experimental-numerical correlation were noted and hypotheses for the discrepancies were given for further investigation. The goal of this work is to refine the experimental measurement and numerical modeling approaches in order to better understand the discrepancies, improve the correlation between prediction and measurement, and provide rigorous quantitative validation of the numerical model. Thermal buckling, post-buckling, and random responses to thermal and inertial (base acceleration) loads are studied. Excellent agreement is achieved between the predicted and measured results, thereby quantitatively validating the numerical tool.

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

    NASA Astrophysics Data System (ADS)

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

    2017-01-01

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

  20. Standardization of the experimental autoimmune myasthenia gravis (EAMG) model by immunization of rats with Torpedo californica acetylcholine receptors — Recommendations for methods and experimental designs

    PubMed Central

    Losen, Mario; Martinez-Martinez, Pilar; Molenaar, Peter C.; Lazaridis, Konstantinos; Tzartos, Socrates; Brenner, Talma; Duan, Rui-Sheng; Luo, Jie; Lindstrom, Jon; Kusner, Linda

    2015-01-01

    Myasthenia gravis (MG) with antibodies against the acetylcholine receptor (AChR) is characterized by a chronic, fatigable weakness of voluntary muscles. The production of autoantibodies involves the dysregulation of T cells which provide the environment for the development of autoreactive B cells. The symptoms are caused by destruction of the postsynaptic membrane and degradation of the AChR by IgG autoantibodies, predominantly of the G1 and G3 subclasses. Active immunization of animals with AChR from mammalian muscles, AChR from Torpedo or Electrophorus electric organs, and recombinant or synthetic AChR fragments generates a chronic model of MG, termed experimental autoimmune myasthenia gravis (EAMG). This model covers cellular mechanisms involved in the immune response against the AChR, e.g. antigen presentation, T cell-help and regulation, B cell selection and differentiation into plasma cells. Our aim is to define standard operation procedures and recommendations for the rat EAMG model using purified AChR from the Torpedo californica electric organ, in order to facilitate more rapid translation of preclinical proof of concept or efficacy studies into clinical trials and, ultimately, clinical practice. PMID:25796590

  1. Cutting Edge: Nanogel-Based Delivery of an Inhibitor of CaMK4 to CD4+ T Cells Suppresses Experimental Autoimmune Encephalomyelitis and Lupus-like Disease in Mice.

    PubMed

    Otomo, Kotaro; Koga, Tomohiro; Mizui, Masayuki; Yoshida, Nobuya; Kriegel, Christina; Bickerton, Sean; Fahmy, Tarek M; Tsokos, George C

    2015-12-15

    Treatment of autoimmune diseases is still largely based on the use of systemically acting immunosuppressive drugs, which invariably cause severe side effects. Calcium/calmodulin-dependent protein kinase IV is involved in the suppression of IL-2 and the production of IL-17. Its pharmacologic or genetic inhibition limits autoimmune disease in mice. In this study, we demonstrate that KN93, a small-molecule inhibitor of calcium/calmodulin-dependent protein kinase IV, targeted to CD4(+) T cells via a nanolipogel delivery system, markedly reduced experimental autoimmune encephalomyelitis and was 10-fold more potent than the free systemically delivered drug in the lupus mouse models. The targeted delivery of KN93 did not deplete T cells but effectively blocked Th17 cell differentiation and expansion as measured in the spinal cords and kidneys of mice developing experimental autoimmune encephalomyelitis or lupus, respectively. These results highlight the promise of cell-targeted inhibition of molecules involved in the pathogenesis of autoimmunity as a means of advancing the treatment of autoimmune diseases. Copyright © 2015 by The American Association of Immunologists, Inc.

  2. Experimental and theoretical investigation on the molecular structure, spectroscopic and electric properties of 2,4-dinitrodiphenylamine, 2-nitro-4-(trifluoromethyl)aniline and 4-bromo-2-nitroaniline.

    PubMed

    Hernández-Paredes, Javier; Hernández-Negrete, Ofelia; Carrillo-Torres, Roberto C; Sánchez-Zeferino, Raúl; Duarte-Moller, Alberto; Alvarez-Ramos, Mario E

    2015-10-05

    2,4-Dinitrodiphenylamine (I), 2-nitro-4-(trifluoromethyl)aniline (II) and 4-bromo-2-nitroaniline (III) have been investigated by DFT and experimental FTIR, Raman and UV-Vis spectroscopies. The gas-phase molecular geometries were consistent with similar compounds already reported in the literature. From the vibrational analysis, the main functional groups were identified and their absorption bands were assigned. Some differences were found between the calculated and the experimental UV-Vis spectra. These differences were analyzed and explained in terms of the TD-DFT/B3LYP limitations, which were mainly attributed to charge-transfer (CT) effects. These findings were in agreement with previous works, which reported that TD-DFT/B3LYP calculations diverge from experimental results when the electronic transitions involve CT. Despite this, TD-DFT/B3LYP calculations provided satisfactory results and a detailed description of the electronic transitions involved in the absorption bands of the UV-Vis spectra. In terms of the NLO properties, it was found that compound (I) is a good candidate for NLO applications and deserves further study due to its good β values. However, the β values for compounds (II) and (III) were negatively affected compared to those found on o-nitroaniline. Copyright © 2015 Elsevier B.V. All rights reserved.

  3. Prediction of Psilocybin Response in Healthy Volunteers

    PubMed Central

    Studerus, Erich; Gamma, Alex; Kometer, Michael; Vollenweider, Franz X.

    2012-01-01

    Responses to hallucinogenic drugs, such as psilocybin, are believed to be critically dependent on the user's personality, current mood state, drug pre-experiences, expectancies, and social and environmental variables. However, little is known about the order of importance of these variables and their effect sizes in comparison to drug dose. Hence, this study investigated the effects of 24 predictor variables, including age, sex, education, personality traits, drug pre-experience, mental state before drug intake, experimental setting, and drug dose on the acute response to psilocybin. The analysis was based on the pooled data of 23 controlled experimental studies involving 409 psilocybin administrations to 261 healthy volunteers. Multiple linear mixed effects models were fitted for each of 15 response variables. Although drug dose was clearly the most important predictor for all measured response variables, several non-pharmacological variables significantly contributed to the effects of psilocybin. Specifically, having a high score in the personality trait of Absorption, being in an emotionally excitable and active state immediately before drug intake, and having experienced few psychological problems in past weeks were most strongly associated with pleasant and mystical-type experiences, whereas high Emotional Excitability, low age, and an experimental setting involving positron emission tomography most strongly predicted unpleasant and/or anxious reactions to psilocybin. The results confirm that non-pharmacological variables play an important role in the effects of psilocybin. PMID:22363492

  4. Prediction of psilocybin response in healthy volunteers.

    PubMed

    Studerus, Erich; Gamma, Alex; Kometer, Michael; Vollenweider, Franz X

    2012-01-01

    Responses to hallucinogenic drugs, such as psilocybin, are believed to be critically dependent on the user's personality, current mood state, drug pre-experiences, expectancies, and social and environmental variables. However, little is known about the order of importance of these variables and their effect sizes in comparison to drug dose. Hence, this study investigated the effects of 24 predictor variables, including age, sex, education, personality traits, drug pre-experience, mental state before drug intake, experimental setting, and drug dose on the acute response to psilocybin. The analysis was based on the pooled data of 23 controlled experimental studies involving 409 psilocybin administrations to 261 healthy volunteers. Multiple linear mixed effects models were fitted for each of 15 response variables. Although drug dose was clearly the most important predictor for all measured response variables, several non-pharmacological variables significantly contributed to the effects of psilocybin. Specifically, having a high score in the personality trait of Absorption, being in an emotionally excitable and active state immediately before drug intake, and having experienced few psychological problems in past weeks were most strongly associated with pleasant and mystical-type experiences, whereas high Emotional Excitability, low age, and an experimental setting involving positron emission tomography most strongly predicted unpleasant and/or anxious reactions to psilocybin. The results confirm that non-pharmacological variables play an important role in the effects of psilocybin.

  5. On the mechanism of the palladium catalyzed intramolecular Pauson-Khand-type reaction.

    PubMed

    Lan, Yu; Deng, Lujiang; Liu, Jing; Wang, Can; Wiest, Olaf; Yang, Zhen; Wu, Yun-Dong

    2009-07-17

    Density functional theory calculations and experimental studies have been carried out on the intramolecular Pauson-Khand-Type reaction mediated by a PdCl(2)-thiourea catalyst, which proceeds under mild reaction conditions and provides a useful alternative to traditional Pauson-Khand reactions. The classical mechanism of the Pauson-Khand reaction involving the alkyne/alkene C-C bond formation as the key step has been found to be energetically unfavorable and is not in line with the experimental observations. A novel reaction mechanism has been proposed for the reaction. The first step involves the cis-halometalation of the alkyne, followed by sequential alkene and carbonyl insertion. The rate-determining fourth step is an intramolecular C-Cl oxidative addition, leading to a Pd(IV) intermediate. A C-C bond formation by reductive elimination completes the reaction. The mechanism is in agreement with the key experimental observations including (1) the need of a chloride for catalytic activity and the absence of catalysis with Pd(OAc)(2) alone; (2) the rate acceleration by the addition of LiCl; both with PdCl(2) and Pd(OAc)(2) catalysts; and (3) the preferred formation of the trans diastereomer in substituted cases. The cis halometalation and the formation and stability of the Pd(IV) intermediate is studied in detail and provides general insights into these novel steps.

  6. Placebo studies and ritual theory: a comparative analysis of Navajo, acupuncture and biomedical healing

    PubMed Central

    Kaptchuk, Ted J.

    2011-01-01

    Using a comparative analysis of Navajo healing ceremonials, acupuncture and biomedical treatment, this essay examines placebo studies and ritual theory as mutually interpenetrating disciplines. Healing rituals create a receptive person susceptible to the influences of authoritative culturally sanctioned ‘powers’. The healer provides the sufferer with imaginative, emotional, sensory, moral and aesthetic input derived from the palpable symbols and procedures of the ritual process—in the process fusing the sufferer's idiosyncratic narrative unto a universal cultural mythos. Healing rituals involve a drama of evocation, enactment, embodiment and evaluation in a charged atmosphere of hope and uncertainty. Experimental research into placebo effects demonstrates that routine biomedical pharmacological and procedural interventions contain significant ritual dimensions. This research also suggests that ritual healing not only represents changes in affect, self-awareness and self-appraisal of behavioural capacities, but involves modulations of symptoms through neurobiological mechanisms. Recent scientific investigations into placebo acupuncture suggest several ways that observations from ritual studies can be verified experimentally. Placebo effects are often described as ‘non-specific’; the analysis presented here suggests that placebo effects are the ‘specific’ effects of healing rituals. PMID:21576142

  7. Final Technical Report for Department of Energy award number DE-FG02-06ER54882, Revised

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

    Eggleston, Dennis L.

    The research reported here involves studies of radial particle transport in a cylindrical, low-density Malmberg-Penning non-neutral plasma trap. The research is primarily experimental but involves careful comparisons to analytical theory and includes the results of a single-particle computer code. The transport is produced by applied electric fields that break the cylindrical symmetry of the trap, hence the term ``asymmetry-induced transport.'' Our computer studies have revealed the importance of a previously ignored class of particles that become trapped in the asymmetry potential. In many common situations these particles exhibit large radial excursions and dominate the radial transport. On the experimental side,more » we have developed new data analysis techniques that allowed us to determine the magnetic field dependence of the transport and to place empirical constraints on the form on the transport equation. Experiments designed to test the computer code results gave varying degrees of agreement with further work being necessary to understand the results. This work expands our knowledge of the varied mechanisms of cross-magnetic-field transport and should be of use to other workers studying plasma confinement.« less

  8. A review of the nest protection hypothesis: does inclusion of fresh green plant material in birds' nests reduce parasite infestation?

    PubMed

    Scott-Baumann, James F; Morgan, Eric R

    2015-07-01

    The use of aromatic plants and their essential oils for ectoparasite treatment is a field of growing interest. Several species of birds regularly introduce aromatic herbs into their nests putatively to reduce parasites. The behaviour is most often seen in cavity nesting birds and after nest building has finished. The plants are included in a non-structural manner and are often strongly aromatic. Various different hypotheses have been proposed regarding the function of this behaviour; from the plants altering some non-living factor in the nest (crypsis, water loss and insulation hypotheses) to them being involved in mate selection (mate hypothesis) or even having a beneficial effect, direct or indirect, on chicks (drug or nest protection hypothesis, NPH). Many studies have been carried out over the years observing and experimentally testing these hypotheses. This review focuses on studies involving the most popular of these hypotheses, the NPH: that plants decrease nest parasites or pathogens, thereby conveying positive effects to the chicks, allowing the behaviour to evolve. Studies providing observational evidence towards this hypothesis and those experimentally testing it are discussed.

  9. Aspergillosis in waterfowl

    USGS Publications Warehouse

    Herman, Carlton M.; Sladen, William J. L.

    1958-01-01

    Aspergillosis, a respiratory disease most commonly caused by the fungus Aspergillus fumigatus, although frequently the cause of losses in captive birds, has been little studied in wild waterfowl and other avian species. Evidence indicates this to be of importance in the wild, and studies were conducted to determine factors relating to its epizoology. Field collections from corn and other plants have yielded infective spores of Aspergillus which were inoculated into experimental chickens and ducklings and then re-isolated from characteristic lesions. A technique was developed for inoculating suspensions of known numbers of spores directly into one of the posterior thoracic airsacs. It was demonstrated that less than one million spores of A. fumigatus killed less than one-half of the experimental chickens, 10 million spores killed over 80 per cent and 50 million killed all inoculated chickens as well as ducklings. Older birds were able to survive as many as 500 million spores except when in a weakened condition. Chickens usually started dying within two days after inoculation while those that survived as long as 11 days usually fully recovered by three weeks. Pathological involvement usually was confined to lungs and airsacs. The procedures and techniques involved in these studies were illustrated on a color motion picture.

  10. Development of a step-down method for altering male C57BL/6 mouse housing density and hierarchical structure: Preparations for spaceflight studies

    NASA Astrophysics Data System (ADS)

    Scofield, David C.; Rytlewski, Jeffrey D.; Childress, Paul; Shah, Kishan; Tucker, Aamir; Khan, Faisal; Peveler, Jessica; Li, Ding; McKinley, Todd O.; Chu, Tien-Min G.; Hickman, Debra L.; Kacena, Melissa A.

    2018-05-01

    This study was initiated as a component of a larger undertaking designed to study bone healing in microgravity aboard the International Space Station (ISS). Spaceflight experimentation introduces multiple challenges not seen in ground studies, especially with regard to physical space, limited resources, and inability to easily reproduce results. Together, these can lead to diminished statistical power and increased risk of failure. It is because of the limited space, and need for improved statistical power by increasing sample size over historical numbers, NASA studies involving mice require housing mice at densities higher than recommended in the Guide for the Care and Use of Laboratory Animals (National Research Council, 2011). All previous NASA missions in which mice were co-housed, involved female mice; however, in our spaceflight studies examining bone healing, male mice are required for optimal experimentation. Additionally, the logistics associated with spaceflight hardware and our study design necessitated variation of density and cohort make up during the experiment. This required the development of a new method to successfully co-house male mice while varying mouse density and hierarchical structure. For this experiment, male mice in an experimental housing schematic of variable density (Spaceflight Correlate) analogous to previously established NASA spaceflight studies was compared to a standard ground based housing schematic (Normal Density Controls) throughout the experimental timeline. We hypothesized that mice in the Spaceflight Correlate group would show no significant difference in activity, aggression, or stress when compared to Normal Density Controls. Activity and aggression were assessed using a novel activity scoring system (based on prior literature, validated in-house) and stress was assessed via body weights, organ weights, and veterinary assessment. No significant differences were detected between the Spaceflight Correlate group and the Normal Density Controls in activity, aggression, body weight, or organ weight, which was confirmed by veterinary assessments. Completion of this study allowed for clearance by NASA of our bone healing experiments aboard the ISS, and our experiment was successfully launched February 19, 2017 on SpaceX CRS-10.

  11. Development of a step-down method for altering male C57BL/6 mouse housing density and hierarchical structure: Preparations for spaceflight studies.

    PubMed

    Scofield, David C; Rytlewski, Jeffrey D; Childress, Paul; Shah, Kishan; Tucker, Aamir; Khan, Faisal; Peveler, Jessica; Li, Ding; McKinley, Todd O; Chu, Tien-Min G; Hickman, Debra L; Kacena, Melissa A

    2018-05-01

    This study was initiated as a component of a larger undertaking designed to study bone healing in microgravity aboard the International Space Station (ISS). Spaceflight experimentation introduces multiple challenges not seen in ground studies, especially with regard to physical space, limited resources, and inability to easily reproduce results. Together, these can lead to diminished statistical power and increased risk of failure. It is because of the limited space, and need for improved statistical power by increasing sample size over historical numbers, NASA studies involving mice require housing mice at densities higher than recommended in the Guide for the Care and Use of Laboratory Animals (National Research Council, 2011). All previous NASA missions in which mice were co-housed, involved female mice; however, in our spaceflight studies examining bone healing, male mice are required for optimal experimentation. Additionally, the logistics associated with spaceflight hardware and our study design necessitated variation of density and cohort make up during the experiment. This required the development of a new method to successfully co-house male mice while varying mouse density and hierarchical structure. For this experiment, male mice in an experimental housing schematic of variable density (Spaceflight Correlate) analogous to previously established NASA spaceflight studies was compared to a standard ground based housing schematic (Normal Density Controls) throughout the experimental timeline. We hypothesized that mice in the Spaceflight Correlate group would show no significant difference in activity, aggression, or stress when compared to Normal Density Controls. Activity and aggression were assessed using a novel activity scoring system (based on prior literature, validated in-house) and stress was assessed via body weights, organ weights, and veterinary assessment. No significant differences were detected between the Spaceflight Correlate group and the Normal Density Controls in activity, aggression, body weight, or organ weight, which was confirmed by veterinary assessments. Completion of this study allowed for clearance by NASA of our bone healing experiments aboard the ISS, and our experiment was successfully launched February 19, 2017 on SpaceX CRS-10. Copyright © 2018 The Committee on Space Research (COSPAR). Published by Elsevier Ltd. All rights reserved.

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

    NASA Astrophysics Data System (ADS)

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

    2013-04-01

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

  13. Standardised animal models of host microbial mutualism

    PubMed Central

    Macpherson, A J; McCoy, K D

    2015-01-01

    An appreciation of the importance of interactions between microbes and multicellular organisms is currently driving research in biology and biomedicine. Many human diseases involve interactions between the host and the microbiota, so investigating the mechanisms involved is important for human health. Although microbial ecology measurements capture considerable diversity of the communities between individuals, this diversity is highly problematic for reproducible experimental animal models that seek to establish the mechanistic basis for interactions within the overall host-microbial superorganism. Conflicting experimental results may be explained away through unknown differences in the microbiota composition between vivaria or between the microenvironment of different isolated cages. In this position paper, we propose standardised criteria for stabilised and defined experimental animal microbiotas to generate reproducible models of human disease that are suitable for systematic experimentation and are reproducible across different institutions. PMID:25492472

  14. Experimental models of demyelination and remyelination.

    PubMed

    Torre-Fuentes, L; Moreno-Jiménez, L; Pytel, V; Matías-Guiu, J A; Gómez-Pinedo, U; Matías-Guiu, J

    2017-08-29

    Experimental animal models constitute a useful tool to deepen our knowledge of central nervous system disorders. In the case of multiple sclerosis, however, there is no such specific model able to provide an overview of the disease; multiple models covering the different pathophysiological features of the disease are therefore necessary. We reviewed the different in vitro and in vivo experimental models used in multiple sclerosis research. Concerning in vitro models, we analysed cell cultures and slice models. As for in vivo models, we examined such models of autoimmunity and inflammation as experimental allergic encephalitis in different animals and virus-induced demyelinating diseases. Furthermore, we analysed models of demyelination and remyelination, including chemical lesions caused by cuprizone, lysolecithin, and ethidium bromide; zebrafish; and transgenic models. Experimental models provide a deeper understanding of the different pathogenic mechanisms involved in multiple sclerosis. Choosing one model or another depends on the specific aims of the study. Copyright © 2017 Sociedad Española de Neurología. Publicado por Elsevier España, S.L.U. All rights reserved.

  15. Poly(ADP-ribose) polymerase inhibition reveals a potential mechanism to promote neuroprotection and treat neuropathic pain.

    PubMed

    Komirishetty, Prashanth; Areti, Aparna; Gogoi, Ranadeep; Sistla, Ramakrishna; Kumar, Ashutosh

    2016-10-01

    Neuropathic pain is triggered by the lesions to peripheral nerves which alter their structure and function. Neuroprotective approaches that limit the pathological changes and improve the behavioral outcome have been well explained in different experimental models of neuropathy but translation of such strategies to clinics has been disappointing. Experimental evidences revealed the role of free radicals, especially peroxynitrite after the nerve injury. They provoke oxidative DNA damage and consequent over-activation of the poly(ADP-ribose) polymerase (PARP) upregulates pro-inflammatory pathways, causing bioenergetic crisis and neuronal death. Along with these changes, it causes mitochondrial dysfunction leading to neuronal apoptosis. In related preclinical studies agents that neutralize the free radicals and pharmacological inhibitors of PARP have shown benefits in treating experimental neuropathy. This article reviews the involvement of PARP over-activation in trauma induced neuropathy and therapeutic significance of PARP inhibitors in the experimental neuropathy and neuropathic pain.

  16. Reducing emotional reasoning: an experimental manipulation in individuals with fear of spiders.

    PubMed

    Lommen, Miriam J J; Engelhard, Iris M; van den Hout, Marcel A; Arntz, Arnoud

    2013-01-01

    Emotional reasoning involves the tendency to use subjective responses to make erroneous inferences about situations (e.g., "If I feel anxious, there must be danger") and has been implicated in various anxiety disorders. The aim of this study of individuals with fear of spiders was to test whether computerised experimental training, compared to control training, would decrease emotional reasoning, reduce fear-related danger beliefs, and increase approach behaviour towards a fear-relevant stimulus. Effects were assessed shortly after the experimental manipulation and one day later. Results showed that the manipulation significantly decreased emotional reasoning in the experimental condition, not in the control condition, and resulted in lower danger estimates of a spider, which was maintained up to one day later. No differences in approach behaviour towards the spider were found. Reducing emotional reasoning may ultimately help patients with anxiety disorders attend more to objective situational information to correct erroneous danger beliefs.

  17. 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.

  18. Experimental results for a hypersonic nozzle/afterbody flow field

    NASA Technical Reports Server (NTRS)

    Spaid, Frank W.; Keener, Earl R.; Hui, Frank C. L.

    1995-01-01

    This study was conducted to experimentally characterize the flow field created by the interaction of a single-expansion ramp-nozzle (SERN) flow with a hypersonic external stream. Data were obtained from a generic nozzle/afterbody model in the 3.5 Foot Hypersonic Wind Tunnel at the NASA Ames Research Center, in a cooperative experimental program involving Ames and McDonnell Douglas Aerospace. The model design and test planning were performed in close cooperation with members of the Ames computational fluid dynamics (CFD) team for the National Aerospace Plane (NASP) program. This paper presents experimental results consisting of oil-flow and shadow graph flow-visualization photographs, afterbody surface-pressure distributions, rake boundary-layer measurements, Preston-tube skin-friction measurements, and flow field surveys with five-hole and thermocouple probes. The probe data consist of impact pressure, flow direction, and total temperature profiles in the interaction flow field.

  19. Fructo-oligosaccharide effects on blood glucose: an overview.

    PubMed

    Costa, Graciana Teixeira; Guimarães, Sergio Botelho; Sampaio, Helena Alves de Carvalho

    2012-03-01

    To identify the current status of scientific knowledge in fructo-oligosaccharides (FOS), non-conventional sugars that play an important role in glycemia control. We performed a search for scientific articles in MEDLINE and LILACS databases, from January 1962 to December 2011, using English/Portuguese key words: "blood glucose/glicemia", "prebiotics/prebióticos" and "dietary fiber/fibras na dieta". From an initial number of 434 references, some repeated, 43 references published from 1962 to 2011 were included in this study. The selected texts were distributed in three topics: (1) metabolism of FOS, (2) FOS and experimental studies involving glucose and (3) human studies involving glucose and FOS. Five studies have shown that the use of FOS reduces the fecal content and increases intestinal transit time. Experimental studies have shown that dietary supplementation with high doses (60 g/Kg) of propionate, a short-chain fatty acid decreased glycemia. The use of lower doses (3 g/kg) did not produce the same results. Study in subjects with diabetes type II showed that the addition of 8 grams of FOS in the diet for 14 days, caused a reduction in serum glucose. In another study with healthy subjects, there were no changes in glycemic control. This review demonstrates that consumption of FOS has a beneficial influence on glucose metabolism. The controversies appear to be due to inadequate methodological designs and/or the small number of individuals included in some studies.

  20. Challenging Density Functional Theory Calculations with Hemes and Porphyrins

    PubMed Central

    de Visser, Sam P.; Stillman, Martin J.

    2016-01-01

    In this paper we review recent advances in computational chemistry and specifically focus on the chemical description of heme proteins and synthetic porphyrins that act as both mimics of natural processes and technological uses. These are challenging biochemical systems involved in electron transfer as well as biocatalysis processes. In recent years computational tools have improved considerably and now can reproduce experimental spectroscopic and reactivity studies within a reasonable error margin (several kcal·mol−1). This paper gives recent examples from our groups, where we investigated heme and synthetic metal-porphyrin systems. The four case studies highlight how computational modelling can correctly reproduce experimental product distributions, predicted reactivity trends and guide interpretation of electronic structures of complex systems. The case studies focus on the calculations of a variety of spectroscopic features of porphyrins and show how computational modelling gives important insight that explains the experimental spectra and can lead to the design of porphyrins with tuned properties. PMID:27070578

  1. Experimental identification of closely spaced modes using NExT-ERA

    NASA Astrophysics Data System (ADS)

    Hosseini Kordkheili, S. A.; Momeni Massouleh, S. H.; Hajirezayi, S.; Bahai, H.

    2018-01-01

    This article presents a study on the capability of the time domain OMA method, NExT-ERA, to identify closely spaced structural dynamic modes. A survey in the literature reveals that few experimental studies have been conducted on the effectiveness of the NExT-ERA methodology in case of closely spaced modes specifically. In this paper we present the formulation for NExT-ERA. This formulation is then implemented in an algorithm and a code, developed in house to identify the modal parameters of different systems using their generated time history data. Some numerical models are firstly investigated to validate the code. Two different case studies involving a plate with closely spaced modes and a pulley ring with greater extent of closeness in repeated modes are presented. Both structures are excited by random impulses under the laboratory condition. The resulting time response acceleration data are then used as input in the developed code to extract modal parameters of the structures. The accuracy of the results is checked against those obtained from experimental tests.

  2. Analysis of Nonplanar Wing-tip-mounted Lifting Surfaces on Low-speed Airplanes

    NASA Technical Reports Server (NTRS)

    Vandam, C. P.; Roskam, J.

    1983-01-01

    Nonplanar wing tip mounted lifting surfaces reduce lift induced drag substantially. Winglets, which are small, nearly vertical, winglike surfaces, are an example of these devices. To achieve reduction in lift induced drag, winglets produce significant side forces. Consequently, these surfaces can seriously affect airplane lateral directional aerodynamic characteristics. Therefore, the effects of nonplanar wing tip mounted surfaces on the lateral directional stability and control of low speed general aviation airplanes were studied. The study consists of a theoretical and an experimental, in flight investigation. The experimental investigation involves flight tests of winglets on an agricultural airplane. Results of these tests demonstrate the significant influence of winglets on airplane lateral directional aerodynamic characteristics. It is shown that good correlations exist between experimental data and theoretically predicted results. In addition, a lifting surface method was used to perform a parametric study of the effects of various winglet parameters on lateral directional stability derivatives of general aviation type wings.

  3. [The relationship between the placebo effect and spontaneous improvement in research on antidepressants. Are placebos powerless?].

    PubMed

    Hougaard, Esben

    2005-08-08

    Clinical trials of antidepressant medications have generally found large changes in groups given a placebo, which may be due to either spontaneous remission or a true placebo effect. This paper reviews the evidence for a true placebo effect in the treatment of unipolar depressed outpatients. Although there is no evidence from experimental studies, a rather substantial amount of circumstantial evidence indicates a true placebo effect. This article raises the question of whether it is meaningful to require experimental evidence for a loose and unspecified concept involving varying components such as placebo.

  4. Computational Design of Functionalized Metal–Organic Framework Nodes for Catalysis

    PubMed Central

    2017-01-01

    Recent progress in the synthesis and characterization of metal–organic frameworks (MOFs) has opened the door to an increasing number of possible catalytic applications. The great versatility of MOFs creates a large chemical space, whose thorough experimental examination becomes practically impossible. Therefore, computational modeling is a key tool to support, rationalize, and guide experimental efforts. In this outlook we survey the main methodologies employed to model MOFs for catalysis, and we review selected recent studies on the functionalization of their nodes. We pay special attention to catalytic applications involving natural gas conversion. PMID:29392172

  5. Observation of linear and quadratic magnetic field-dependence of magneto-photocurrents in InAs/GaSb superlattice

    PubMed Central

    2014-01-01

    We experimentally studied the magneto-photocurrents generated by direct interband transition in InAs/GaSb type II superlattice. By varying the magnetic field direction, we observed that an in-plane magnetic field induces a photocurrent linearly proportional to the magnetic field; however, a magnetic field tilted to the sample plane induces a photocurrent presenting quadratic magnetic field dependence. The magneto-photocurrents in both conditions are insensitive to the polarization state of the incident light. Theoretical models involving excitation, relaxation and Hall effect are utilized to explain the experimental results. PMID:24936166

  6. Breakdown of ionic character of molecular alkali bromides in inner-valence photoionization

    NASA Astrophysics Data System (ADS)

    Karpenko, A.; Iablonskyi, D.; Urpelainen, S.; Kettunen, J. A.; Cao, W.; Huttula, M.; Aksela, H.

    2014-05-01

    The inner-valence region of alkali bromide XBr (X=Li, Na, K, Rb) vapours has been studied experimentally by means of synchrotron radiation excited photoelectron spectroscopy. Experimental spectra were analyzed by comparing them with available theoretical results and previous experiments. Ionic character of alkali bromides is seen to change in the inner-valence region with increasing atomic number of the alkali atom. A mechanism involving mixing between Br 4s and Rb 4p orbitals has been suggested to account for the fine structure observed in inner-valence ionization region of RbBr.

  7. Four Years of Farmer Experimentation on Soil Fertility in Tigray, Northern Ethiopia: Trends in Research Strategies

    ERIC Educational Resources Information Center

    Kraaijvanger, Richard G.; Veldkamp, Tom

    2017-01-01

    Purpose: This paper analyses research strategies followed by farmer groups in Tigray, that were involved in participatory experimentation. Understanding choices made by farmers in such experimentation processes is important to understand reasons why farmers in Tigray often hesitated to adopt recommended practices. Design/Methodology/Approach: A…

  8. 75 FR 71699 - Pesticide Experimental Use Permits; Receipt of Amendment and Extension Applications; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-24

    ... ENVIRONMENTAL PROTECTION AGENCY [EPA-HQ-OPP-2010-0926; FRL-8853-7] Pesticide Experimental Use... and 264-EUP-143 from Bayer CropScience LP requesting to amend and extend the existing experimental use... fair treatment and meaningful involvement of any group, including minority and/or low income...

  9. 75 FR 53371 - Liquefied Natural Gas Facilities: Obtaining Approval of Alternative Vapor-Gas Dispersion Models

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-08-31

    ... factors as the approved models, are validated by experimental test data, and receive the Administrator's... stage of the MEP involves applying the model against a database of experimental test cases including..., particularly the requirement for validation by experimental test data. That guidance is based on the MEP's...

  10. Limbic control of aggression in the cat.

    PubMed

    Adamec, R E; Stark-Adamec, C I

    1983-01-01

    Over a decade of work by Flynn and colleagues has delineated a network of limbic circuits which function to modulate the expression of predatory aggression and defence in the cat, and aspects of this work are reviewed. In particular, Flynn's work revealed a circuit involving the basomedial amygdala which functions to suppress attack, and at the same time facilitates defence. A second circuit, involving the ventral hippocampus, is involved in attack facilitation. Studies relating stable differences in excitability in these two circuits to developmentally determined behavioural dispositions toward aggression or defence are summarized. Finally, the impact of experimentally induced limbic seizures on interictally maintained expression of aggression and defence behaviourally, and on limbic excitability are reviewed. Taken together, the data indicate that the behavioural balance of attack and defence is under the tonic control of opponent limbic circuits, which are themselves biased in a measureable manner. Developmental studies indicate that adult defensiveness is determined early in life, so early as to suggest some pre-programmed neuro-developmental process. Experimentally induced seizures alter behaviour lastingly, producing an increase in defensive disposition. At the same time there is an equally lasting potentiation of interictal transmission of neural activity from the amygdala to the hypothalamus. Moreover, seizures may reduce interictal transmission of activity through the ventral hippocampus by potentiating recurrent inhibition. These effects of seizures are of interest since seizures reproduce naturally occurring differences in limbic excitability seen in naturally defensive cats.

  11. Neural correlates of social exclusion across ages: A coordinate-based meta-analysis of functional MRI studies.

    PubMed

    Vijayakumar, Nandita; Cheng, Theresa W; Pfeifer, Jennifer H

    2017-06-01

    Given the recent surge in functional neuroimaging studies on social exclusion, the current study employed activation likelihood estimation (ALE) based meta-analyses to identify brain regions that have consistently been implicated across different experimental paradigms used to investigate exclusion. We also examined the neural correlates underlying Cyberball, the most commonly used paradigm to study exclusion, as well as differences in exclusion-related activation between developing (7-18 years of age, from pre-adolescence up to late adolescence) and emerging adult (broadly defined as undergraduates, including late adolescence and young adulthood) samples. Results revealed involvement of the bilateral medial prefrontal and posterior cingulate cortices, right precuneus and left ventrolateral prefrontal cortex across the different paradigms used to examine social exclusion; similar activation patterns were identified when restricting the analysis to Cyberball studies. Investigations into age-related effects revealed that ventrolateral prefrontal activations identified in the full sample were driven by (i.e. present in) developmental samples, while medial prefrontal activations were driven by emerging adult samples. In addition, the right ventral striatum was implicated in exclusion, but only in developmental samples. Subtraction analysis revealed significantly greater activation likelihood in striatal and ventrolateral prefrontal clusters in the developmental samples as compared to emerging adults, though the opposite contrast failed to identify any significant regions. Findings integrate the knowledge accrued from functional neuroimaging studies on social exclusion to date, highlighting involvement of lateral prefrontal regions implicated in regulation and midline structures involved in social cognitive and self-evaluative processes across experimental paradigms and ages, as well as limbic structures in developing samples specifically. Copyright © 2017 Elsevier Inc. All rights reserved.

  12. Experimental and theoretical charge density studies at subatomic resolution.

    PubMed

    Fischer, A; Tiana, D; Scherer, W; Batke, K; Eickerling, G; Svendsen, H; Bindzus, N; Iversen, B B

    2011-11-17

    Analysis of accurate experimental and theoretical structure factors of diamond and silicon reveals that the contraction of the core shell due to covalent bond formation causes significant perturbations of the total charge density that cannot be ignored in precise charge density studies. We outline that the nature and origin of core contraction/expansion and core polarization phenomena can be analyzed by experimental studies employing an extended Hansen-Coppens multipolar model. Omission or insufficient treatment of these subatomic charge density phenomena might yield erroneous thermal displacement parameters and high residual densities in multipolar refinements. Our detailed studies therefore suggest that the refinement of contraction/expansion and population parameters of all atomic shells is essential to the precise reconstruction of electron density distributions by a multipolar model. Furthermore, our results imply that also the polarization of the inner shells needs to be adopted, especially in cases where second row or even heavier elements are involved in covalent bonding. These theoretical studies are supported by direct multipolar refinements of X-ray powder diffraction data of diamond obtained from a third-generation synchrotron-radiation source (SPring-8, BL02B2).

  13. Report of Total Involvement Professional Semester TIPS.

    ERIC Educational Resources Information Center

    Payne, James I.

    The goal of the Total Involvement Professional Semester (TIPS) was to allow elementary education students at Shippensburg State College to become involved in an educational environment in a meaningful way to develop their professional knowledge and skills. The experimental program consisted of five important components: a) three weeks of…

  14. Reducing physical size limits for low-frequency horn loudspeaker systems

    NASA Astrophysics Data System (ADS)

    Honeycutt, Richard Allison

    From 1881 until the present day, many excellent scholars have studied acoustic horns. This dissertation begins by discussing over eighty results of such study. Next, the methods of modeling horn behavior are examined with an emphasis on the prediction of throat impedance. Because of the time constraints in a product-design environment, in which the results of this study may be used, boundary-element and cascaded-section types of analysis were not considered due to their time intensiveness. Of the methods studied, an analytical process based upon Olson's adaptation of Webster's analysis is selected as the most accurate of the rapid methods, although other good methods exist. Reasons and extent of inaccuracy are discussed. The concept of interleaved horn loading is introduced: it involves using two horns of different parameters, fed by a single driver, with a view toward interleaving and thus smoothing the impedance peaks of the separate horns to produce a smoother response. The validity of the technique is demonstrated both theoretically and practically. Then the reactance annulling technique is explained and tested experimentally. It is found to work well, but the exact parameter values involved are not found to be critical. Finally, the considerations involved in building a practical working system are discussed, and a preliminary working model reviewed. Future work could be directed toward finding the optimum parameter values for the two "parallel horns" whose impedances are to be interleaved, as well as the system parameters that determine these optimum values. Also, further experimental investigation or ported loading of the back air chamber would be useful.

  15. A processing centre for the CNES CE-GPS experimentation

    NASA Technical Reports Server (NTRS)

    Suard, Norbert; Durand, Jean-Claude

    1994-01-01

    CNES is involved in a GPS (Global Positioning System) geostationary overlay experimentation. The purpose of this experimentation is to test various new techniques in order to select the optimal station synchronization method, as well as the geostationary spacecraft orbitography method. These new techniques are needed to develop the Ranging GPS Integrity Channel services. The CNES experimentation includes three transmitting/receiving ground stations (manufactured by IN-SNEC), one INMARSAT 2 C/L band transponder and a processing center named STE (Station de Traitements de l'Experimentation). Not all the techniques to be tested are implemented, but the experimental system has to include several functions; part of the future system simulation functions, such as a servo-loop function, and in particular a data collection function providing for rapid monitoring of system operation, analysis of existing ground station processes, and several weeks of data coverage for other scientific studies. This paper discusses system architecture and some criteria used in its design, as well as the monitoring function, the approach used to develop a low-cost and short-life processing center in collaboration with a CNES sub-contractor (ATTDATAID), and some results.

  16. Protective effect of proanthocyanidins on endotoxin induced experimental periodontitis in rats.

    PubMed

    Govindaraj, Jayamathi; Emmadi, Pamela; Deepalakshmi; Rajaram, Vijayalakshmi; Prakash, Geetha; Puvanakrishnan, Rengarajulu

    2010-02-01

    The pathogenesis of periodontitis involves anaerobic oral bacteria as well as the host response to infection and several drugs have been developed which can curtail these deleterious effects. Proanthocyanidin, a novel flavanoid extracted from grape seeds, has been shown to provide a significant therapeutic effect on endotoxin (Escherichia coli) induced experimental periodontitis in rats. In this study, protective action of different doses of proanthocyanidins was investigated in blood by assaying the reactive oxygen species such as hydrogen peroxide, superoxide anion, myeloperoxidase and lipid peroxides, lysosomal enzyme activities such as cathepsin B, cathepsin D, beta-glucuronidase and acid phosphatase, nonenzymatic antioxidants such as ascorbic acid, alpha-tocopherol, ceruloplasmin, reduced glutathione and antioxidant enzymes such as catalase, superoxide dismutase, glutathione peroxidase and glutathione-s-transferase. Experimental periodontitis rats showed a reduction in body weight and body weight gain could be noticed when they were administered proanthocyanidins. The levels of reactive oxygen species and lysosomal enzymes were found to increase whereas antioxidant levels were decreased significantly in experimental periodontitis. Proanthocyanidins at an effective dose of 30 mg/kg body weight, sc, for 30 days effected a decrease in serum reactive oxygen species, lipid peroxides, lysosomal enzymes, acute phase proteins and an increase in antioxidant levels. Histopathological evidence of experimental periodontitis showed cellular infiltration of inflammatory cells while proanthocyanidin treated groups demonstrated only scattered inflammatory cells and blood vessels. Thus, the results showed that dietary supplementation of proanthocyanidin enhanced the host resistance as well as the inhibition of the biological and mechanical irritants involved in the onset of gingivitis and the progression of periodontal disease.

  17. Changes in mode of travel to work: a natural experimental study of new transport infrastructure.

    PubMed

    Heinen, Eva; Panter, Jenna; Mackett, Roger; Ogilvie, David

    2015-06-20

    New transport infrastructure may promote a shift towards active travel, thereby improving population health. The purpose of this study was to determine the effect of a major transport infrastructure project on commuters' mode of travel, trip frequency and distance travelled to work. Quasi-experimental analysis nested within a cohort study of 470 adults working in Cambridge, UK. The intervention consisted of the opening of a guided busway with a path for walking and cycling in 2011. Exposure to the intervention was defined as the negative of the square root of the shortest distance from home to busway. The outcome measures were changes in commute mode share and number of commute trips - both based on a seven-day travel-to-work record collected before (2009) and after (2012) the intervention - and change in objective commute distance. The mode share outcomes were changes in the proportions of trips (i) involving any active travel, (ii) involving any public transport, and (iii) made entirely by car. Separate multinomial regression models were estimated adjusting for commute and sociodemographic characteristics, residential settlement size and life events. Proximity to the busway predicted an increased likelihood of a large (>30 %) increase in the share of commute trips involving any active travel (relative risk ratio [RRR] 1.80, 95 % CI 1.27, 2.55) and a large decrease in the share of trips made entirely by car (RRR 2.09, 95 % CI 1.35, 3.21), as well as a lower likelihood of a small (<30 %) reduction in the share of trips involving any active travel (RRR 0.47, 95 % CI 0.28, 0.81). It was not associated with changes in the share of commute trips involving any public transport, the number of commute trips, or commute distance. The new infrastructure promoted an increase in the share of commuting trips involving active travel and a decrease in the share made entirely by car. Further analysis will show the extent to which the changes in commute mode share were translated into an increase in time spent in active commuting and consequent health gain.

  18. Genesis of Prolactinomas: Studies Using Estrogen-Treated Animals

    PubMed Central

    Sarkar, Dipak K.

    2010-01-01

    Prolactin-secreting adenomas (prolactinomas) are the most prevalent form of pituitary tumors in humans. Our knowledge of the formation of these tumors is limited. Experimental work in animal has uncovered that estradiol exposure leads to prolactinoma formation via orchestrated events involving dopamine D2 receptors, transforming growth factor-β (TGF-β) isoforms and their receptors, as well as factors secondary to TGF-β action. Additionally, these studies determined that TGF-β and b-FGF interact to facilitate the communication between lactotropes and folliculo-stellate cells that is necessary for the mitogenic action of estradiol. The downstream signaling that governs lactotropic cell proliferation involves activation of the MAP kinase p44/42-dependent pathway. PMID:16809921

  19. Experimentally-induced maternal hypothyroidism alters crucial enzyme activities in the frontal cortex and hippocampus of the offspring rat.

    PubMed

    Koromilas, Christos; Tsakiris, Stylianos; Kalafatakis, Konstantinos; Zarros, Apostolos; Stolakis, Vasileios; Kimpizi, Despoina; Bimpis, Alexios; Tsagianni, Anastasia; Liapi, Charis

    2015-02-01

    Thyroid hormone insufficiency during neurodevelopment can result into significant structural and functional changes within the developing central nervous system (CNS), and is associated with the establishment of serious cognitive impairment and neuropsychiatric symptomatology. The aim of the present study was to shed more light on the effects of gestational and/or lactational maternal exposure to propylthiouracil (PTU)-induced hypothyroidism as a multilevel experimental approach to the study of hypothyroidism-induced changes on crucial brain enzyme activities of 21-day-old Wistar rat offspring in a brain region-specific manner. This experimental approach has been recently developed and characterized by the authors based on neurochemical analyses performed on newborn and 21-day-old rat offspring whole brain homogenates; as a continuum to this effort, the current study focused on two CNS regions of major significance for cognitive development: the frontal cortex and the hippocampus. Maternal exposure to PTU in the drinking water during gestation and/or lactation resulted into changes in the activities of acetylcholinesterase and two important adenosinetriphosphatases (Na(+),K(+)- and Mg(2+)-ATPase), that seemed to take place in a CNS-region-specific manner and that were dependent upon the PTU-exposure timeframe followed. As these findings are analyzed and compared to the available literature, they: (i) highlight the variability involved in the changes of the aforementioned enzymatic parameters in the studied CNS regions (attributed to both the different neuroanatomical composition and the thyroid-hormone-dependent neurodevelopmental growth/differentiation patterns of the latter), (ii) reveal important information with regards to the neurochemical mechanisms that could be involved in the way clinical hypothyroidism could affect optimal neurodevelopment and, ultimately, cognitive function, as well as (iii) underline the need for the adoption of more consistent approaches towards the experimental simulation of congenital and early-age-occurring hypothyroidism.

  20. Family members' involvement in elder care provision in nursing homes and their considerations about financial compensation: a qualitative study.

    PubMed

    Habjanič, Ana; Pajnkihar, Majda

    2013-01-01

    The aim of this study was to establish how family members are involved in elder care provision in nursing homes; this included research into their feelings about potentially extending their involvement to obtain financial benefits as compensation for high accommodation costs. Family members remain involved in the caring process after their relatives have been admitted to an institution. On average, accommodation costs in nursing homes in Slovenia have risen above the residents' retirement pension, and families must supplement the difference. Because of this, familial involvement should be linked to reduced accommodation costs. This research employed a non-experimental, descriptive study design through unstructured interviews. Participants included fifty family members (n=50) who visit their relatives in nursing homes. Data were collected in 2010 at five nursing homes in Slovenia and processed by means of conventional content analysis. The major themes that emerged from the content analysis, describing family involvement, were as follows: visiting and making oneself useful, delivery of items for personal use, hands-on care, physical therapy and organization of nursing home activities. Family members showed some interest in receiving financial compensation for their involvement. The proposed financial compensation may be a delicate and morally questionable matter but would involve fairness and transparency, while enabling easier organization of elder care provision. Eventually, nursing home residents' well-being could be improved. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  1. Using decoy effects to influence an online brand choice: the role of price-quality trade-offs.

    PubMed

    Hsu, Huei-Chen; Liu, Wen-Liang

    2011-04-01

    This research aims to investigate decoy effects on online brand choices. To assess the influence of decoys, we test decoy effects on three constructs-product involvement, judgment conditions, and decoy conditions-within an online experiment. A survey of 635 Internet users and a 2 × 2 × 3 ANOVA between-subjects experimental design is used to guide the research design and the systematic analysis procedure. A major finding of this study is that a standard decoy seems to have a significant effect on an advertised (target) brand for high-involvement products; from the survey, it is also apparent that competitors can also use inferior decoys to increase brand preference for low-involvement products.

  2. Concept Verification Test - Evaluation of Spacelab/Payload operation concepts

    NASA Technical Reports Server (NTRS)

    Mcbrayer, R. O.; Watters, H. H.

    1977-01-01

    The Concept Verification Test (CVT) procedure is used to study Spacelab operational concepts by conducting mission simulations in a General Purpose Laboratory (GPL) which represents a possible design of Spacelab. In conjunction with the laboratory a Mission Development Simulator, a Data Management System Simulator, a Spacelab Simulator, and Shuttle Interface Simulator have been designed. (The Spacelab Simulator is more functionally and physically representative of the Spacelab than the GPL.) Four simulations of Spacelab mission experimentation were performed, two involving several scientific disciplines, one involving life sciences, and the last involving material sciences. The purpose of the CVT project is to support the pre-design and development of payload carriers and payloads, and to coordinate hardware, software, and operational concepts of different developers and users.

  3. United States Air Force Summer Faculty Research Program for 1990. Program Management Report

    DTIC Science & Technology

    1991-06-05

    propagation characteristics were extensively studied using pencil lead breaks in a center notch. For the fatigue studies center crack samples of 2024 - T351 ... aluminum specimens during fatigue cycling. The experimental procedure involved excitation of Rayleigh waves on the surface of each specimen and...Research Program (SFRP) provides opportunities for research in the physical sciences, engineering, and life sciences. The program has been effective

  4. Development of an electron paramagnetic resonance methodology for studying the photo-generation of reactive species in semiconductor nano-particle assembled films

    NASA Astrophysics Data System (ADS)

    Twardoch, Marek; Messai, Youcef; Vileno, Bertrand; Hoarau, Yannick; Mekki, Djamel E.; Felix, Olivier; Turek, Philippe; Weiss, Jean; Decher, Gero; Martel, David

    2018-06-01

    An experimental approach involving electron paramagnetic resonance is proposed for studying photo-generated reactive species in semiconductor nano-particle-based films deposited on the internal wall of glass capillaries. This methodology is applied here to nano-TiO2 and allows a semi-quantitative analysis of the kinetic evolutions of radical production using a spin scavenger probe.

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

    ERIC Educational Resources Information Center

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

    2004-01-01

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

  6. El Impacto de Textos en Contextos Familiares en Comunidades de Practica para la Adquisicion de Vocabulario y Estructuras Gramaticales de Español Inicial Acelerado

    ERIC Educational Resources Information Center

    Burgos, Francisco

    2014-01-01

    This study, which involved classroom-based experimental research conducted during the Fall semester of 2013 in a Spanish class at Oakwood University, aimed at extending the findings of previous studies on the use of familiar texts in reading and writing (Brown 2007, Vygotsky 1978, Kern 2000, Rollins & Villamil 2001, McCourt 2006, Morris, Beck…

  7. A solid-state [sup 13]C NMR study of the molecular motion of ethylene adsorbed on a silver surface

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

    Jianxin Wang; Ellis, P.D.

    1993-01-13

    The reorientation of ethylene on a silver catalyst surface has been studied by solid-state [sup 13]C NMR. The static cross-polarization spectra at different temperatures have been measured. Different jump site models are proposed to simulate the experimental results. It was found that the models involving a low number of jump sites are more sensitive to the experimental details. By comparison of the simulated and experimental results, the 6- and 4-site jump models are chosen as the most satisfactory model to fit the experimental spectra. On the basis of this representation, the activation energy derived for the jump process is 4.3more » kJ/mol. From the simulated results, it was concluded that the symmetry axis for the motion of the ethylene at low temperatures ([minus]173 to ca. [minus]45[degrees]C) is perpendicular to the plane of the ethylene molecule. At higher temperatures motion about other axes is initiated such that at room temperature a nearly isotropically averaged [sup 13]C shielding tensor is observed. 20 refs., 9 figs.« less

  8. New Experimental Models of Diabetic Nephropathy in Mice Models of Type 2 Diabetes: Efforts to Replicate Human Nephropathy

    PubMed Central

    Soler, María José; Riera, Marta; Batlle, Daniel

    2012-01-01

    Diabetic nephropathy (DN) is the leading cause of end-stage renal disease. The use of experimental models of DN has provided valuable information regarding many aspects of DN, including pathophysiology, progression, implicated genes, and new therapeutic strategies. A large number of mouse models of diabetes have been identified and their kidney disease was characterized to various degrees. Most experimental models of type 2 DN are helpful in studying early stages of DN, but these models have not been able to reproduce the characteristic features of more advanced DN in humans such as nodules in the glomerular tuft or glomerulosclerosis. The generation of new experimental models of DN created by crossing, knockdown, or knockin of genes continues to provide improved tools for studying DN. These models provide an opportunity to search for new mechanisms involving the development of DN, but their shortcomings should be recognized as well. Moreover, it is important to recognize that the genetic background has a substantial effect on the susceptibility to diabetes and kidney disease development in the various models of diabetes. PMID:22461787

  9. Experimental Impacts of a Preschool Intervention in Chile on Children's Language Outcomes: Moderation by Student Absenteeism

    ERIC Educational Resources Information Center

    Arbour, MaryCatherine; Yoshikawa, Hirokazu; Willett, John; Weiland, Christina; Snow, Catherine; Mendive, Susana; Barata, M. Clara; Treviño, Ernesto

    2016-01-01

    Despite consensus that school absenteeism has negative consequences for children's life outcomes, until recently, little was known about the prevalence of absenteeism or its potential to moderate the impacts of school-based interventions. This study provides evidence from a randomized experiment of a preschool intervention involving 1,876 children…

  10. Campus Community Involvement in an Experimental Food Research Project Increases Students' Motivation and Improves Perceived Learning Outcomes

    ERIC Educational Resources Information Center

    Goto, K.; Bianco-Simeral, S.

    2009-01-01

    Although the effects of pedagogical strategies using collaborative learning on students' perceived learning outcomes have been studied, little has been examined about possible benefits and challenges in collaborating with the campus community in a food science research project conducted by nutrition majors. We examined the effects of involving…

  11. Intensive group selection silviculture in central hardwoods

    Treesearch

    Leon S. Minckler

    1989-01-01

    In 1947 conferences of Forest Service research people from Federal, Regional, and Research Center units met in Southern Illinois to set up in 1948 a whole rotation study on the Kaskaskia Experimental Forest involving 38 commercial compartments. The chief objectives were to evaluate the success, ability for sustained silviculture, and the costs and returns for a full...

  12. Energy: Light, Sound, and Heat, Science (Experimental): 5311.04.

    ERIC Educational Resources Information Center

    Castaldi, June P.

    This unit of instruction was designed as a basic course involving the study of light, sound, and heat at the junior high school level. The booklet lists the relevant state-adopted texts and states the performance objectives for the unit. It provides an outline of the course content and suggests experiments, demonstrations, field trips, and topics…

  13. Mind the Gap! Students' Use of Exemplars and Detailed Rubrics as Formative Assessment

    ERIC Educational Resources Information Center

    Lipnevich, Anastasiya A.; McCallen, Leigh N.; Miles, Katharine Pace; Smith, Jeffrey K.

    2014-01-01

    The current study examined efficient modes for providing standardized feedback to improve performance on an assignment for a second year college class involving writing a brief research proposal. Two forms of standardized feedback (detailed rubric and proposal exemplars) were utilized is an experimental design with undergraduate students (N = 100)…

  14. Learning Nonadjacent Dependencies: No Need for Algebraic-Like Computations

    ERIC Educational Resources Information Center

    Perruchet, Pierre; Tyler, Michael D.; Galland, Nadine; Peereman, Ronald

    2004-01-01

    Is it possible to learn the relation between 2 nonadjacent events? M. Pena, L. L. Bonatti, M. Nespor, and J. Mehler (2002) claimed this to be possible, but only in conditions suggesting the involvement of algebraic-like computations. The present article reports simulation studies and experimental data showing that the observations on which Pe?a et…

  15. Effects Of Rapid Crushing On Composites

    NASA Technical Reports Server (NTRS)

    Farley, Gary L.

    1990-01-01

    Experimental study described in NASA technical memorandum performed to determine whether crash energy-absorption capabilities of graphite/epoxy and Kevlar/epoxy composite materials are functions of speed of crushing. Additional objective to develop understanding of mechanisms of crushing. Technology applied to enhancement of safety and crashworthiness of automobiles, design of energy-absorbing devices in machinery, and problems involving explosions and impacts.

  16. The Effects of an Audio-Visual Training Program in Dyslexic Children

    ERIC Educational Resources Information Center

    Magnan, Annie; Ecalle, Jean; Veuillet, Evelyne; Collet, Lionel

    2004-01-01

    A research project was conducted in order to investigate the usefulness of intensive audio-visual training administered to children with dyslexia involving daily voicing exercises. In this study, the children received such voicing training (experimental group) for 30 min a day, 4 days a week, over 5 weeks. They were assessed on a reading task…

  17. Hydraulic Fracturing in Zoned Earth and Rockfill Dams: A Report of an Investigation.

    DTIC Science & Technology

    The investigation involves two parts: first, an experimental investigation to study the phenomenon of hydraulic fracturing under carefully...be reduced sufficiently by arching so that hydraulic fracturing can occur. Analyses were also performed to examine the effectiveness of various countermeasures which can reduce the arching and the likelihood of hydraulic fracturing .

  18. Three-Level Analysis of Single-Case Experimental Data: Empirical Validation

    ERIC Educational Resources Information Center

    Moeyaert, Mariola; Ugille, Maaike; Ferron, John M.; Beretvas, S. Natasha; Van den Noortgate, Wim

    2014-01-01

    One approach for combining single-case data involves use of multilevel modeling. In this article, the authors use a Monte Carlo simulation study to inform applied researchers under which realistic conditions the three-level model is appropriate. The authors vary the value of the immediate treatment effect and the treatment's effect on the time…

  19. The Gran Plot Analysis of an Acid Mixture. An Undergraduate Experiment to Highlight this Alternate Method.

    ERIC Educational Resources Information Center

    Boiani, James A.

    1986-01-01

    Describes an experiment which uses the Gran plot for analyzing free ions as well as those involved in an equilibrium. Discusses the benefits of using Gran plots in the study of acids, as well as other analytes in solutions. Presents background theory along with a description of the experimental procedures. (TW)

  20. Persistence of Learning Gains from Computer Assisted Learning: Experimental Evidence from China

    ERIC Educational Resources Information Center

    Mo, D.; Zhang, L.; Wang, J.; Huang, W.; Shi, Y.; Boswell, M.; Rozelle, S.

    2015-01-01

    Computer assisted learning (CAL) programs have been shown to be effective in improving educational outcomes. However, the existing studies on CAL have almost all been conducted over a short period of time. There is very little evidence on how the impact evolves over time. In response, we conducted a clustered randomized experiment involving 2741…

  1. What Contributes to the Split-Attention Effect? The Role of Text Segmentation, Picture Labelling, and Spatial Proximity

    ERIC Educational Resources Information Center

    Florax, Mareike; Ploetzner, Rolf

    2010-01-01

    In the split-attention effect spatial proximity is frequently considered to be pivotal. The transition from a spatially separated to a spatially integrated format not only involves changes in spatial proximity, but commonly necessitates text segmentation and picture labelling as well. In an experimental study, we investigated the influence of…

  2. The Thermoregulatory Consequences of Heat Stroke: Are Cytokines Involved

    DTIC Science & Technology

    2006-01-01

    71 6. Ambient temperature effects on heat stroke outcome ... exposure , the effectiveness of this treatment following administration directly into the hy- pothalamus was not tested (Lin et al., 1994). In addition, it is...versus that of heat exposure on experimental outcome (i.e., mortality). However, ethical concerns regarding the use of mortality as a study endpoint

  3. An Experimental Evaluation of Hyperactivity and Food Additives. 1977-Phase II.

    ERIC Educational Resources Information Center

    Harley, J. Preston; And Others

    Phase II of a study on the effectiveness of B. Feingold's recommended diet for hyperactive children involved the nine children (mean age 9 years) who had shown the "best" response to diet manipulation in Phase I. Each child served as his own control and was challenged with specified amounts of placebo and artificial color containing food…

  4. Social Identity Change: Shifts in Social Identity during Adolescence

    ERIC Educational Resources Information Center

    Tanti, Chris; Stukas, Arthur A.; Halloran, Michael J.; Foddy, Margaret

    2011-01-01

    This study investigated the proposition that adolescence involves significant shifts in social identity as a function of changes in social context and cognitive style. Using an experimental design, we primed either peer or gender identity with a sample of 380 early- (12-13 years), mid- (15-16 years), and late-adolescents (18-20 years) and then…

  5. Temperature Dependence Of Single-Event Effects

    NASA Technical Reports Server (NTRS)

    Coss, James R.; Nichols, Donald K.; Smith, Lawrence S.; Huebner, Mark A.; Soli, George A.

    1990-01-01

    Report describes experimental study of effects of temperature on vulnerability of integrated-circuit memories and other electronic logic devices to single-event effects - spurious bit flips or latch-up in logic state caused by impacts of energetic ions. Involved analysis of data on 14 different device types. In most cases examined, vulnerability to these effects increased or remain constant with temperature.

  6. Development of Fourth-Grade Students' Understanding of Experimental and Theoretical Probability

    ERIC Educational Resources Information Center

    English, Lyn; Watson, Jane

    2014-01-01

    Students explored variation and expectation in a probability activity at the end of the first year of a 3-year longitudinal study across grades 4-6. The activity involved experiments in tossing coins both manually and with simulation using the graphing software, "TinkerPlots." Initial responses indicated that the students were aware of…

  7. Experimental mixes to minimize rutting.

    DOT National Transportation Integrated Search

    1990-01-01

    This report describes the materials and construction details involved in the design and placement of four experimental mixes on I-95 (Richmond- Petersburg Turnpike) in 1985 and follows the performance for 48 months. The mixes were designed to resist ...

  8. Brownian Motion--a Laboratory Experiment.

    ERIC Educational Resources Information Center

    Kruglak, Haym

    1988-01-01

    Introduces an experiment involving the observation of Brownian motion for college students. Describes the apparatus, experimental procedures, data analysis and results, and error analysis. Lists experimental techniques used in the experiment. Provides a circuit diagram, typical data, and graphs. (YP)

  9. The Ca(2+)-EDTA chelation as standard reaction to validate Isothermal Titration Calorimeter measurements (ITC).

    PubMed

    Ràfols, Clara; Bosch, Elisabeth; Barbas, Rafael; Prohens, Rafel

    2016-07-01

    A study about the suitability of the chelation reaction of Ca(2+)with ethylenediaminetetraacetic acid (EDTA) as a validation standard for Isothermal Titration Calorimeter measurements has been performed exploring the common experimental variables (buffer, pH, ionic strength and temperature). Results obtained in a variety of experimental conditions have been amended according to the side reactions involved in the main process and to the experimental ionic strength and, finally, validated by contrast with the potentiometric reference values. It is demonstrated that the chelation reaction performed in acetate buffer 0.1M and 25°C shows accurate and precise results and it is robust enough to be adopted as a standard calibration process. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Recent Progress on the VASIMR

    NASA Technical Reports Server (NTRS)

    ChangDiaz, Franklin R.; Squire, J. P.; Ilin, A. V.; Jacobson, V. T.; Glover, T. W.; Baity, F. W.; Carter, M. D.; Goulding, R. H.; Breizman, B. N.

    1999-01-01

    Experimental and theoretical studies on the Variable Specific Impulse Magnetoplasma Rocket (VASIMR) have continued through a NASA led collaborative program involving several research groups. In the experimental area, performance characterization of the VASIMR helicon plasma source has been obtained over a portion of the parameter space, with helium and hydrogen propellant. Density (10(exp 18) - 10(exp 19)/ cubic meter) and temperature (5 eV) were measured at moderate degree of ionization in two separate experimental devices. Helicon design improvement and optimization will be discussed. Experiments with the ion cyclotron resonance heating (ICRH) subsection have begun and preliminary results will be discussed. Theoretical picture and integrated numerical simulation continue to be refined to account for the main physics elements of the VASIMR, including RF absorption and particle acceleration with subsequent detachment in the magnetic nozzle.

  11. Hybrid power system intelligent operation and protection involving distributed architectures and pulsed loads

    NASA Astrophysics Data System (ADS)

    Mohamed, Ahmed

    Efficient and reliable techniques for power delivery and utilization are needed to account for the increased penetration of renewable energy sources in electric power systems. Such methods are also required for current and future demands of plug-in electric vehicles and high-power electronic loads. Distributed control and optimal power network architectures will lead to viable solutions to the energy management issue with high level of reliability and security. This dissertation is aimed at developing and verifying new techniques for distributed control by deploying DC microgrids, involving distributed renewable generation and energy storage, through the operating AC power system. To achieve the findings of this dissertation, an energy system architecture was developed involving AC and DC networks, both with distributed generations and demands. The various components of the DC microgrid were designed and built including DC-DC converters, voltage source inverters (VSI) and AC-DC rectifiers featuring novel designs developed by the candidate. New control techniques were developed and implemented to maximize the operating range of the power conditioning units used for integrating renewable energy into the DC bus. The control and operation of the DC microgrids in the hybrid AC/DC system involve intelligent energy management. Real-time energy management algorithms were developed and experimentally verified. These algorithms are based on intelligent decision-making elements along with an optimization process. This was aimed at enhancing the overall performance of the power system and mitigating the effect of heavy non-linear loads with variable intensity and duration. The developed algorithms were also used for managing the charging/discharging process of plug-in electric vehicle emulators. The protection of the proposed hybrid AC/DC power system was studied. Fault analysis and protection scheme and coordination, in addition to ideas on how to retrofit currently available protection concepts and devices for AC systems in a DC network, were presented. A study was also conducted on the effect of changing the distribution architecture and distributing the storage assets on the various zones of the network on the system's dynamic security and stability. A practical shipboard power system was studied as an example of a hybrid AC/DC power system involving pulsed loads. Generally, the proposed hybrid AC/DC power system, besides most of the ideas, controls and algorithms presented in this dissertation, were experimentally verified at the Smart Grid Testbed, Energy Systems Research Laboratory. All the developments in this dissertation were experimentally verified at the Smart Grid Testbed.

  12. Assessing the scientific research productivity of a leading toxicology journal: A case study of Human & Experimental Toxicology from 2003 to 2012.

    PubMed

    Zyoud, Sa'ed H; Al-Jabi, Samah W; Sweileh, Waleed M; Awang, Rahmat

    2014-01-01

    Bibliometric studies are increasingly being used for research assessments. Bibliometric indicators involve the application of statistical methods to scientific publications to obtain the bibliographics for each journal. The main objective of this study was to conduct a bibliometric evaluation of Human & Experimental Toxicology retrieved from the Scopus database. This study obtained data from Scopus published from 1 January 2003 till 31 December 2012. The keywords entered in Scopus to accomplish the objective of this study were 'Human', 'Experimental' and 'Toxicology' as 'Source Title'. Research productivity was evaluated based on a methodology developed and used in other bibliometric studies by analysing (a) total and trends in Human & Experimental Toxicology contributions in research between 2003 and 2012; (b) Human & Experimental Toxicology authorship patterns and productivity; (c) collaboration patterns; and (d) the citations received by the publications. There were 1229 research articles published in Human & Experimental Toxicology. Of the articles included, 947 (77.1%) were original articles and 104 (8.5%) were review articles. The Hirsch-index of the retrieved documents was 35. The largest number of publications in Human & Experimental Toxicology was from the United States (19.6%), followed by India (12.8%) and Turkey (10.9%). The total number of citations was 9119, with a median (interquartile range) of 3 (1-9) in 6797 documents. The highest median (interquartile range) number of citations was 8 (2.7-12.7) for France, followed by 7.5 (2-22.5) for Iran and 6 (3-13.5) for the United Kingdom. The country most often citing articles that were published in Human & Experimental Toxicology was the United States, which made citations in 1508 documents, followed by India with citations in 792 documents. The documents in Human & Experimental Toxicology focus principally on original data, with very few review articles. Review articles tend to have higher citation rates than original articles, and hence, the editors and authors of Human & Experimental Toxicology might usefully promote the submission of reviews in the future to improve the impact of the journal.

  13. Advanced Reactors-Intermediate Heat Exchanger (IHX) Coupling: Theoretical Modeling and Experimental Validation

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

    Utgikar, Vivek; Sun, Xiaodong; Christensen, Richard

    2016-12-29

    The overall goal of the research project was to model the behavior of the advanced reactorintermediate heat exchange system and to develop advanced control techniques for off-normal conditions. The specific objectives defined for the project were: 1. To develop the steady-state thermal hydraulic design of the intermediate heat exchanger (IHX); 2. To develop mathematical models to describe the advanced nuclear reactor-IHX-chemical process/power generation coupling during normal and off-normal operations, and to simulate models using multiphysics software; 3. To develop control strategies using genetic algorithm or neural network techniques and couple these techniques with the multiphysics software; 4. To validate themore » models experimentally The project objectives were accomplished by defining and executing four different tasks corresponding to these specific objectives. The first task involved selection of IHX candidates and developing steady state designs for those. The second task involved modeling of the transient and offnormal operation of the reactor-IHX system. The subsequent task dealt with the development of control strategies and involved algorithm development and simulation. The last task involved experimental validation of the thermal hydraulic performances of the two prototype heat exchangers designed and fabricated for the project at steady state and transient conditions to simulate the coupling of the reactor- IHX-process plant system. The experimental work utilized the two test facilities at The Ohio State University (OSU) including one existing High-Temperature Helium Test Facility (HTHF) and the newly developed high-temperature molten salt facility.« less

  14. Histological Methods for ex vivo Axon Tracing: A Systematic Review

    PubMed Central

    Heilingoetter, Cassandra L.; Jensen, Matthew B.

    2016-01-01

    Objectives Axon tracers provide crucial insight into the development, connectivity, and function of neural pathways. A tracer can be characterized as a substance that allows for the visualization of a neuronal pathway. Axon tracers have previously been used exclusively with in vivo studies; however, newer methods of axon tracing can be applied to ex vivo studies. Ex vivo studies involve the examination of cells or tissues retrieved from an organism. These post mortem methods of axon tracing offer several advantages, such as reaching inaccessible tissues and avoiding survival surgeries. Methods In order to evaluate the quality of the ex vivo tracing methods, we performed a systematic review of various experimental and comparison studies to discern the optimal method of axon tracing. Results The most prominent methods for ex vivo tracing involve enzymatic techniques or various dyes. It appears that there are a variety of techniques and conditions that tend to give better fluorescent character, clarity, and distance traveled in the neuronal pathway. We found direct comparison studies that looked at variables such as the type of tracer, time required, effect of temperature, and presence of calcium, however, there are other variables that have not been compared directly. Discussion We conclude there are a variety of promising tracing methods available depending on the experimental goals of the researcher, however, more direct comparison studies are needed to affirm the optimal method. PMID:27098542

  15. Histological methods for ex vivo axon tracing: A systematic review.

    PubMed

    Heilingoetter, Cassandra L; Jensen, Matthew B

    2016-07-01

    Axon tracers provide crucial insight into the development, connectivity, and function of neural pathways. A tracer can be characterized as a substance that allows for the visualization of a neuronal pathway. Axon tracers have previously been used exclusively with in vivo studies; however, newer methods of axon tracing can be applied to ex vivo studies. Ex vivo studies involve the examination of cells or tissues retrieved from an organism. These post mortem methods of axon tracing offer several advantages, such as reaching inaccessible tissues and avoiding survival surgeries. In order to evaluate the quality of the ex vivo tracing methods, we performed a systematic review of various experimental and comparison studies to discern the optimal method of axon tracing. The most prominent methods for ex vivo tracing involve enzymatic techniques or various dyes. It appears that there are a variety of techniques and conditions that tend to give better fluorescent character, clarity, and distance traveled in the neuronal pathway. We found direct comparison studies that looked at variables such as the type of tracer, time required, effect of temperature, and presence of calcium, however, there are other variables that have not been compared directly. We conclude there are a variety of promising tracing methods available depending on the experimental goals of the researcher, however, more direct comparison studies are needed to affirm the optimal method.

  16. [The experimental models of Parkinson's disease in animals].

    PubMed

    Grigor'ian, G A; Bazian, A S

    2007-01-01

    The current review describes the modem Parkinson's disease models in animals, their advantages, limitations and disadvantages. It was noted that the most widespread up-to-date models based on etiology of the Parkinson's disease. Although toxins mostly produce the Parkinson's disease, a study of involved genes allows investigating not only inherited but also sporadic (not inherited) forms of disease since the same genes are involved in both cases. Mutations of genes lead to formation of "mutant" toxic proteins, which produce a death of the specialized neurons of the nigrostriatal dopaminergic system and the development of Parkinson's disease. A significant place in the review takes adescription of characteristics of the toxic models produced by 6-OHDA, MPTP and rotenone, their similarities and differences in pathogenetic mechanisms of the Parkinson's disease development. On the basis of the considered experimental models of Parkinson's disease a conclusion has been done that none of these models may in full and adequate scale imitate the entire clinical, pathophysiological, morphological, biochemical and other aspects of the Parkinson's disease development.

  17. [Visual input affects the expression of the early genes c-Fos and ZENK in auditory telencephalic centers of pied flycatcher nestlings during the acoustically-guided freezing].

    PubMed

    Korneeva, E V; Tiunova, A A; Aleksandrov, L I; Golubeva, T B; Anokhin, K V

    2014-01-01

    The present study analyzed expression of transcriptional factors c-Fos and ZENK in 9-day-old pied flycatcher nestlings' (Ficedula hypoleuca) telencephalic auditory centers (field L, caudomedial nidopallium and caudomedial mesopallium) involved in the acoustically-guided defense behavior. Species-typical alarm call was presented to the young in three groups: 1--intact group (sighted control), 2--nestlings visually deprived just before the experiment for a short time (unsighted control) 3--nestlings visually deprived right after hatching (experimental deprivation). Induction of c-Fos as well as ZENK in nestlings from the experimental deprivation group was decreased in both hemispheres as compared with intact group. In the group of unsighted control, only the decrease of c-Fos induction was observed exclusively in the right hemisphere. These findings suggest that limitation of visual input changes the population of neurons involved into the acoustically-guided behavior, the effect being dependant from the duration of deprivation.

  18. Enabling CSPA Operations Through Pilot Involvement in Longitudinal Approach Spacing

    NASA Technical Reports Server (NTRS)

    Battiste, Vernol (Technical Monitor); Pritchett, Amy

    2003-01-01

    Several major airports around the United States have, or plan to have, closely-spaced parallel runways. This project complemented current and previous research by examining the pilots ability to control their position longitudinally within their approach stream.This project s results considered spacing for separation from potential positions of wake vortices from the parallel approach. This preventive function could enable CSPA operations to very closely spaced runways. This work also considered how pilot involvement in longitudinal spacing could allow for more efficient traffic flow, by allowing pilots to keep their aircraft within tighter arrival slots then air traffic control (ATC) might be able to establish, and by maintaining space within the arrival stream for corresponding departure slots. To this end, this project conducted several research studies providing an analytic and computational basis for calculating appropriate aircraft spacings, experimental results from a piloted flight simulator test, and an experimental testbed for future simulator tests. The following sections summarize the results of these three efforts.

  19. Avalanching strain dynamics during the hydriding phase transformation in individual palladium nanoparticles

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

    Ulvestad, A.; Welland, M. J.; Collins, S. S. E.

    2015-12-11

    Phase transitions in reactive environments are crucially important in energy and information storage, catalysis and sensors. Nanostructuring active particles can yield faster charging/ discharging kinetics, increased lifespan and record catalytic activities. However, establishing the causal link between structure and function is challenging for nanoparticles, as ensemble measurements convolve intrinsic single-particle properties with sample diversity. Here we study the hydriding phase transformation in individual palladium nanocubes in situ using coherent X-ray diffractive imaging. The phase transformation dynamics, which involve the nucleation and propagation of a hydrogen-rich region, are dependent on absolute time (aging) and involve intermittent dynamics (avalanching). A hydrogen-rich surfacemore » layer dominates the crystal strain in the hydrogen-poor phase, while strain inversion occurs at the cube corners in the hydrogen-rich phase. A three-dimensional phase-field model is used to interpret the experimental results. In conclusion, our experimental and theoretical approach provides a general framework for designing and optimizing phase transformations for single nanocrystals in reactive environments.« less

  20. Numerical Investigation of 'Transonic Resonance' with a Convergent-Divergent Nozzle

    NASA Technical Reports Server (NTRS)

    Loh, Ching Y.; Zaman, K. B. M. Q.

    2002-01-01

    At pressure ratios lower than the design value, convergent-divergent (C-D) nozzles often undergo a flow resonance accompanied by the emission of acoustic tones. The phenomenon, driven by the unsteady shock within the divergent section of the nozzle, has been studied experimentally by Zaman et al. In this paper, the space-time conservation element solution element (CE/SE) method is employed to numerically investigate the phenomenon. The computations are performed for a given nozzle geometry for several different pressure ratios. Sustained 'limit cycle' oscillations are encountered in all cases. The oscillation frequencies, their variation with pressure ratio including a 'stage jump', agree well with the experimental results. The unsteady flow data confirm that stage 1 of the resonance (fundamental) involves a one-quarter standing wave while stage 2 (third harmonic) involves a three-quarter standing wave within the divergent section of the nozzle. Details of the shock motion, and the flow and near acoustic field, are documented for one case each of stages 1 and 2.

  1. Avalanching strain dynamics during the hydriding phase transformation in individual palladium nanoparticles

    NASA Astrophysics Data System (ADS)

    Ulvestad, A.; Welland, M. J.; Collins, S. S. E.; Harder, R.; Maxey, E.; Wingert, J.; Singer, A.; Hy, S.; Mulvaney, P.; Zapol, P.; Shpyrko, O. G.

    2015-12-01

    Phase transitions in reactive environments are crucially important in energy and information storage, catalysis and sensors. Nanostructuring active particles can yield faster charging/discharging kinetics, increased lifespan and record catalytic activities. However, establishing the causal link between structure and function is challenging for nanoparticles, as ensemble measurements convolve intrinsic single-particle properties with sample diversity. Here we study the hydriding phase transformation in individual palladium nanocubes in situ using coherent X-ray diffractive imaging. The phase transformation dynamics, which involve the nucleation and propagation of a hydrogen-rich region, are dependent on absolute time (aging) and involve intermittent dynamics (avalanching). A hydrogen-rich surface layer dominates the crystal strain in the hydrogen-poor phase, while strain inversion occurs at the cube corners in the hydrogen-rich phase. A three-dimensional phase-field model is used to interpret the experimental results. Our experimental and theoretical approach provides a general framework for designing and optimizing phase transformations for single nanocrystals in reactive environments.

  2. Avalanching strain dynamics during the hydriding phase transformation in individual palladium nanoparticles

    PubMed Central

    Ulvestad, A.; Welland, M. J.; Collins, S. S. E.; Harder, R.; Maxey, E.; Wingert, J.; Singer, A.; Hy, S.; Mulvaney, P.; Zapol, P.; Shpyrko, O. G.

    2015-01-01

    Phase transitions in reactive environments are crucially important in energy and information storage, catalysis and sensors. Nanostructuring active particles can yield faster charging/discharging kinetics, increased lifespan and record catalytic activities. However, establishing the causal link between structure and function is challenging for nanoparticles, as ensemble measurements convolve intrinsic single-particle properties with sample diversity. Here we study the hydriding phase transformation in individual palladium nanocubes in situ using coherent X-ray diffractive imaging. The phase transformation dynamics, which involve the nucleation and propagation of a hydrogen-rich region, are dependent on absolute time (aging) and involve intermittent dynamics (avalanching). A hydrogen-rich surface layer dominates the crystal strain in the hydrogen-poor phase, while strain inversion occurs at the cube corners in the hydrogen-rich phase. A three-dimensional phase-field model is used to interpret the experimental results. Our experimental and theoretical approach provides a general framework for designing and optimizing phase transformations for single nanocrystals in reactive environments. PMID:26655832

  3. Miscible viscous fingering with chemical reaction involving precipitation.

    NASA Astrophysics Data System (ADS)

    Bae, Si-Kyun; Nagatsu, Yuichiro; Kato, Yoshihito; Tada, Yutaka

    2007-11-01

    When a reactive and miscible less-viscous liquid displaces a more-viscous liquid in a Hele-Shaw cell, reactive miscible viscous fingering takes place. The present study has experimentally examined how precipitation produced by chemical reaction affects miscible viscous fingering pattern. A 97 wt % glycerin solution containing iron(III) nitrate (yellow) and a solution containing potassium hexacyano ferrate(II) (colorless) were used as the more- and less-viscous liquids, respectively. In this case, the chemical reaction instantaneously takes place and produces the precipitation being dark blue in color. The experiments were done by varying reactant concentrations, the cell's gap width, and the displacement speed. We compared the patterns involving the precipitation reaction with those in the non-reactive cases. We have found fylfot-like pattern is observed, depending on the experimental condition, which has never been formed in the non-reactive experiments. As the reactant concentrations are increased or the displacement speed is decreased, the effects of the precipitation on the patterns are more pronounced.

  4. Synthesis, characterization and relativistic DFT studies of fac-Re(CO)3(isonicotinic acid)2Cl complex

    NASA Astrophysics Data System (ADS)

    Zúñiga, César; Oyarzún, Diego P.; Martin-Transaco, Rudy; Yáñez-S, Mauricio; Tello, Alejandra; Fuentealba, Mauricio; Cantero-López, Plinio; Arratia-Pérez, Ramiro

    2017-11-01

    In this work, new fac-Re(CO)3(PyCOOH)2Cl from isonicotinic acid ligand has been prepared. The complex was characterized by structural (single-crystal X-ray diffraction), elemental analysis and spectroscopic (FTIR, NMR, UV-vis spectroscopy) methods. DFT and TDDFT calculations were performed to obtain the electronic transitions involved in their UV-Vis spectrum. The excitation energies agree with the experimental results. The TDDFT calculations suggest that experimental mixed absorption bands at 270 and 314 nm could be assigned to (MLCT-LLCT)/MLCT transitions. Natural Bond Orbitals (NBO) approach has enabled studying the effects of bonding interactions. E(2) energies confirm the occurrence of ICT (Intra-molecular Charge Transfer) within the molecule.

  5. Statistical process control in nursing research.

    PubMed

    Polit, Denise F; Chaboyer, Wendy

    2012-02-01

    In intervention studies in which randomization to groups is not possible, researchers typically use quasi-experimental designs. Time series designs are strong quasi-experimental designs but are seldom used, perhaps because of technical and analytic hurdles. Statistical process control (SPC) is an alternative analytic approach to testing hypotheses about intervention effects using data collected over time. SPC, like traditional statistical methods, is a tool for understanding variation and involves the construction of control charts that distinguish between normal, random fluctuations (common cause variation), and statistically significant special cause variation that can result from an innovation. The purpose of this article is to provide an overview of SPC and to illustrate its use in a study of a nursing practice improvement intervention. Copyright © 2011 Wiley Periodicals, Inc.

  6. A Discounting Framework for Choice With Delayed and Probabilistic Rewards

    PubMed Central

    Green, Leonard; Myerson, Joel

    2005-01-01

    When choosing between delayed or uncertain outcomes, individuals discount the value of such outcomes on the basis of the expected time to or the likelihood of their occurrence. In an integrative review of the expanding experimental literature on discounting, the authors show that although the same form of hyperbola-like function describes discounting of both delayed and probabilistic outcomes, a variety of recent findings are inconsistent with a single-process account. The authors also review studies that compare discounting in different populations and discuss the theoretical and practical implications of the findings. The present effort illustrates the value of studying choice involving both delayed and probabilistic outcomes within a general discounting framework that uses similar experimental procedures and a common analytical approach. PMID:15367080

  7. Joint surface modeling with thin-plate splines.

    PubMed

    Boyd, S K; Ronsky, J L; Lichti, D D; Salkauskas, K; Chapman, M A; Salkauskas, D

    1999-10-01

    Mathematical joint surface models based on experimentally determined data points can be used to investigate joint characteristics such as curvature, congruency, cartilage thickness, joint contact areas, as well as to provide geometric information well suited for finite element analysis. Commonly, surface modeling methods are based on B-splines, which involve tensor products. These methods have had success; however, they are limited due to the complex organizational aspect of working with surface patches, and modeling unordered, scattered experimental data points. An alternative method for mathematical joint surface modeling is presented based on the thin-plate spline (TPS). It has the advantage that it does not involve surface patches, and can model scattered data points without experimental data preparation. An analytical surface was developed and modeled with the TPS to quantify its interpolating and smoothing characteristics. Some limitations of the TPS include discontinuity of curvature at exactly the experimental surface data points, and numerical problems dealing with data sets in excess of 2000 points. However, suggestions for overcoming these limitations are presented. Testing the TPS with real experimental data, the patellofemoral joint of a cat was measured with multistation digital photogrammetry and modeled using the TPS to determine cartilage thicknesses and surface curvature. The cartilage thickness distribution ranged between 100 to 550 microns on the patella, and 100 to 300 microns on the femur. It was found that the TPS was an effective tool for modeling joint surfaces because no preparation of the experimental data points was necessary, and the resulting unique function representing the entire surface does not involve surface patches. A detailed algorithm is presented for implementation of the TPS.

  8. D-Optimal Experimental Design for Contaminant Source Identification

    NASA Astrophysics Data System (ADS)

    Sai Baba, A. K.; Alexanderian, A.

    2016-12-01

    Contaminant source identification seeks to estimate the release history of a conservative solute given point concentration measurements at some time after the release. This can be mathematically expressed as an inverse problem, with a linear observation operator or a parameter-to-observation map, which we tackle using a Bayesian approach. Acquisition of experimental data can be laborious and expensive. The goal is to control the experimental parameters - in our case, the sparsity of the sensors, to maximize the information gain subject to some physical or budget constraints. This is known as optimal experimental design (OED). D-optimal experimental design seeks to maximize the expected information gain, and has long been considered the gold standard in the statistics community. Our goal is to develop scalable methods for D-optimal experimental designs involving large-scale PDE constrained problems with high-dimensional parameter fields. A major challenge for the OED, is that a nonlinear optimization algorithm for the D-optimality criterion requires repeated evaluation of objective function and gradient involving the determinant of large and dense matrices - this cost can be prohibitively expensive for applications of interest. We propose novel randomized matrix techniques that bring down the computational costs of the objective function and gradient evaluations by several orders of magnitude compared to the naive approach. The effect of randomized estimators on the accuracy and the convergence of the optimization solver will be discussed. The features and benefits of our new approach will be demonstrated on a challenging model problem from contaminant source identification involving the inference of the initial condition from spatio-temporal observations in a time-dependent advection-diffusion problem.

  9. An experimental approach to the fundamental principles of hemodynamics.

    PubMed

    Pontiga, Francisco; Gaytán, Susana P

    2005-09-01

    An experimental model has been developed to give students hands-on experience with the fundamental laws of hemodynamics. The proposed experimental setup is of simple construction but permits the precise measurements of physical variables involved in the experience. The model consists in a series of experiments where different basic phenomena are quantitatively investigated, such as the pressure drop in a long straight vessel and in an obstructed vessel, the transition from laminar to turbulent flow, the association of vessels in vascular networks, or the generation of a critical stenosis. Through these experiments, students acquire a direct appreciation of the importance of the parameters involved in the relationship between pressure and flow rate, thus facilitating the comprehension of more complex problems in hemodynamics.

  10. Role of parnaparin in atherosclerosis.

    PubMed

    Bonomini, Francesca; Taurone, Samanta; Parnigotto, Pierpaolo; Zamai, Loris; Rodella, Luigi F; Artico, Marco; Rezzani, Rita

    2016-12-01

    Atherosclerosis is characterized by a proliferation of vascular smooth muscle cells (VSMCs) and their migration to the intima, which induces thickening of the intima itself, but the mechanism remains poorly understood. Low molecular weight heparin (LMWH) inhibits the proliferation of VSMCs. Previous studies have shown that a LMWH, parnaparin (PNP), acts on the processes of atherogenesis and atheroprogression in experimental animal models. The aim of this study was to investigate the involvement of oxidative stress, inflammation and VSMCs in the regulation of vascular wall homeostasis. We also considered the possibility of restoring vascular pathological changes using PNP treatment. In order to evaluate vascular remodelling in this study we have analysed the morphological changes in aortas of an animal model of atherosclerosis, apolipoprotein E-deficient mice (ApoE-/-) fed with a normal or a western diet without treatment or treated with PNP. We also analysed, by immunohistochemistry, the expression of proteins linked to atherogenesis and atheroprogression - an enzyme involved in oxidative stress, iNOS, examples of inflammatory mediators, such as tumour necrosis factor alpha (TNF-α), interleukins 1 and 6 (IL-1 and IL-6), and markers of VSMC changes, in particular plasminogen activator inhibitor-1 and thrombospondin-1 (PAI-1 and TSP-1). Our results could suggest that PNP downregulates VSMC proliferation and migration, mediated by PAI-1 and TSP-1, and reduces inflammation and oxidative stress in vessels. These data suggested that LMWH, in particular PNP, could be a theoretically practical tool in the prevention of atherosclerotic vascular modification. © 2017 The Authors. International Journal of Experimental Pathology © 2017 International Journal of Experimental Pathology.

  11. Exploring the relationship between time management skills and the academic achievement of African engineering students - a case study

    NASA Astrophysics Data System (ADS)

    Swart, Arthur James; Lombard, Kobus; de Jager, Henk

    2010-03-01

    Poor academic success by African engineering students is currently experienced in many higher educational institutions, contributing to lower financial subsidies by local governments. One of the contributing factors to this low academic success may be the poor time management skills of these students. This article endeavours to explore this relationship by means of a theoretical literature review and an empirical study. Numerous studies have been conducted in this regard, but with mixed results. The case study of this article involves a design module termed Design Projects III, where the empirical study incorporated an ex post facto study involving a pre-experimental/exploratory design using descriptive statistics. The results of this study were applied to various tests, which indicated no statistically significant relationship between time management skills and the academic achievement of African engineering students.

  12. Experimental mixes on Richmond-Petersburg Turnpike, 1985.

    DOT National Transportation Integrated Search

    1986-01-01

    This report describes the materials and construction details involved in the design and placement of four experimental mixes on 1-95 (Richmond-Petersburg Turnpike) between Maury Avenue and Bells Road in 1985. The mixes were designed to initially resi...

  13. Protective pathways against colitis mediated by appendicitis and appendectomy.

    PubMed

    Cheluvappa, R; Luo, A S; Palmer, C; Grimm, M C

    2011-09-01

    Appendicitis followed by appendectomy (AA) at a young age protects against inflammatory bowel disease (IBD). Using a novel murine appendicitis model, we showed that AA protected against subsequent experimental colitis. To delineate genes/pathways involved in this protection, AA was performed and samples harvested from the most distal colon. RNA was extracted from four individual colonic samples per group (AA group and double-laparotomy control group) and each sample microarray analysed followed by gene-set enrichment analysis (GSEA). The gene-expression study was validated by quantitative reverse transcription-polymerase chain reaction (RT-PCR) of 14 selected genes across the immunological spectrum. Distal colonic expression of 266 gene-sets was up-regulated significantly in AA group samples (false discovery rates < 1%; P-value < 0·001). Time-course RT-PCR experiments involving the 14 genes displayed down-regulation over 28 days. The IBD-associated genes tnfsf10, SLC22A5, C3, ccr5, irgm, ptger4 and ccl20 were modulated in AA mice 3 days after surgery. Many key immunological and cellular function-associated gene-sets involved in the protective effect of AA in experimental colitis were identified. The down-regulation of 14 selected genes over 28 days after surgery indicates activation, repression or de-repression of these genes leading to downstream AA-conferred anti-colitis protection. Further analysis of these genes, profiles and biological pathways may assist in developing better therapeutic strategies in the management of intractable IBD. © 2011 The Authors. Clinical and Experimental Immunology © 2011 British Society for Immunology.

  14. Genome scans on experimentally evolved populations reveal candidate regions for adaptation to plant resistance in the potato cyst nematode Globodera pallida.

    PubMed

    Eoche-Bosy, D; Gautier, M; Esquibet, M; Legeai, F; Bretaudeau, A; Bouchez, O; Fournet, S; Grenier, E; Montarry, J

    2017-09-01

    Improving resistance durability involves to be able to predict the adaptation speed of pathogen populations. Identifying the genetic bases of pathogen adaptation to plant resistances is a useful step to better understand and anticipate this phenomenon. Globodera pallida is a major pest of potato crop for which a resistance QTL, GpaV vrn , has been identified in Solanum vernei. However, its durability is threatened as G. pallida populations are able to adapt to the resistance in few generations. The aim of this study was to investigate the genomic regions involved in the resistance breakdown by coupling experimental evolution and high-density genome scan. We performed a whole-genome resequencing of pools of individuals (Pool-Seq) belonging to G. pallida lineages derived from two independent populations having experimentally evolved on susceptible and resistant potato cultivars. About 1.6 million SNPs were used to perform the genome scan using a recent model testing for adaptive differentiation and association to population-specific covariables. We identified 275 outliers and 31 of them, which also showed a significant reduction in diversity in adapted lineages, were investigated for their genic environment. Some candidate genomic regions contained genes putatively encoding effectors and were enriched in SPRYSECs, known in cyst nematodes to be involved in pathogenicity and in (a)virulence. Validated candidate SNPs will provide a useful molecular tool to follow frequencies of virulence alleles in natural G. pallida populations and define efficient strategies of use of potato resistances maximizing their durability. © 2017 John Wiley & Sons Ltd.

  15. Post-exercise blood flow restriction attenuates hyperemia similarly in males and females.

    PubMed

    Dankel, Scott J; Mouser, J Grant; Jessee, Matthew B; Mattocks, Kevin T; Buckner, Samuel L; Loenneke, Jeremy P

    2017-08-01

    Our laboratory recently demonstrated that post-exercise blood flow restriction attenuated muscle hypertrophy only in females, which we hypothesized may be due to alterations in post-exercise blood flow. The aim of this study is to test our previous hypothesis that sex differences in blood flow would exist when employing the same protocol. Twenty-two untrained individuals (12 females; 10 males) performed two exercise sessions, each involving one set of elbow flexion exercise to volitional failure on the right arm. The experimental condition had blood flow restriction applied for a 3 min post-exercise period, whereas the control condition did not. Blood flow was measured using an ultrasound at the brachial artery and was taken 1 and 4 min post-exercise. This corresponded to 1 min post inflation and 1 min post deflation in the experimental condition. There were no differences in the alterations in blood flow between the control and experimental conditions when examined across sex. Increases in blood flow [mean (standard deviation)] were as follows: males 1 min [control 764 (577) %; experimental 113 (108) %], males 4 min [control 346 (313) %; experimental 449 (371) %], females 1 min [control 558 (367) %; experimental 87 (105) %], and females 4 min [control 191 (183) %; experimental 328 (223) %]. It does not appear that the sex-specific attenuation of muscle hypertrophy we observed previously can be attributed to different alterations in post-exercise blood flow. Future studies may wish to replicate our previous training study, or examine alternative mechanisms which may be sex specific.

  16. Effectiveness of Cognitive-behavioral Program on Pain and Fear in School-aged Children Undergoing Intravenous Placement.

    PubMed

    Hsieh, Yi-Chuan; Cheng, Su-Fen; Tsay, Pei-Kwei; Su, Wen-Jen; Cho, Yen-Hua; Chen, Chi-Wen

    2017-12-01

    This study aimed to evaluate the effects of cognitive-behavioral program on pain and medical fear in hospitalized school-aged children receiving intravenous (IV) placement. This study used an quasi-experimental design. Thirty-five participants were assigned to the experimental group and 33 to the control group in the acute internal medicine ward of a children's hospital. The cognitive-behavioral program entailed having the patients read an educational photo book about IV placement before the procedure and having them watch their favorite music video during the procedure. The outcome measures were numeric rating scales for pain intensity and fear during the procedure. After applying the cognitive-behavioral program, the mean scores on pain and fear decreased in the experimental group. However, the difference in pain intensity between these two groups was nonsignificant. The intensity of fear in the experimental group was significantly lower than that in the control group. In this study, the cognitive-behavioral program used with school-aged hospitalized children promoted less fear during IV placement. The results of this study can serve as a reference for empirical nursing care and as care guidance for clinical IV injections involving children. Copyright © 2017. Published by Elsevier B.V.

  17. Deposition and clearance of inhaled particles.

    PubMed Central

    Stuart, B O

    1984-01-01

    Theoretical models of respiratory tract deposition of inhaled particles are compared to experimental studies of deposition patterns in humans and animals, as governed principally by particle size, density, respiratory rate and flow parameters. Various models of inhaled particle deposition make use of approximations of the respiratory tract to predict fractional deposition caused by fundamental physical processes of particle impaction, sedimentation, and diffusion. These models for both total deposition and regional (nasopharyngeal, tracheobronchial, and pulmonary) deposition are compared with early and recent experimental studies. Reasonable correlation has been obtained between theoretical and experimental studies, but the behavior in the respiratory tract of very fine (less than 0.1 micron) particles requires further investigation. Properties of particle shape, charge and hygroscopicity as well as the degree of respiratory tract pathology also influence deposition patterns; definitive experimental work is needed in these areas. The influence upon deposition patterns of dynamic alterations in inspiratory flow profiles caused by a variety of breathing patterns also requires further study, and the use of differing ventilation techniques with selected inhaled particle sizes holds promise in diagnosis of respiratory tract diseases. Mechanisms of conducting airway and alveolar clearance processes involving the pulmonary macrophage, mucociliary clearance, dissolution, transport to systemic circulation, and translocation via regional lymphatic vessels are discussed. PMID:6376108

  18. An ion accelerator for undergraduate research and teaching

    NASA Astrophysics Data System (ADS)

    Monce, Michael

    1997-04-01

    We have recently upgraded our 400kV, single beam line ion accelerator to a 1MV, multiple beam line machine. This upgrade has greatly expanded the opportunities for student involvement in the laboratory. We will describe four areas of work in which students now participate. The first is the continuing research being conducted in excitations produced in ion-molecule collisions, which recently involved the use of digital imaging. The second area of research now opened up by the new accelerator involves PIXE. We are currently beginning a cross disciplinary study of archaeological specimens using PIXE and involving students from both anthropology and physics. Finally, two beam lines from the accelerator will be used for basic work in nuclear physics: Rutherford scattering and nuclear resonances. These two nuclear physics experiments will be integrated into our sophomore-junior level, year-long course in experimental physics.

  19. Lymphoid cell kinetics under continuous low dose-rate gamma irradiation: A comparison study

    NASA Technical Reports Server (NTRS)

    Foster, B. R.

    1975-01-01

    A comparison study was conducted of the effects of continuous low dose-rate gamma irradiation on cell population kinetics of lymphoid tissue (white pulp) of the mouse spleen with findings as they relate to the mouse thymus. Experimental techniques employed included autoradiography and specific labeling with tritiated thymidine (TdR-(h-3)). The problem studied involved the mechanism of cell proliferation of lymphoid tissue of the mouse spleen and thymus under the stress of continuous irradiation at a dose rate of 10 roentgens (R) per day for 105 days (15 weeks). The aim was to determine whether or not a steady state or near-steady state of cell population could be established for this period of time, and what compensatory mechanisms of cell population were involved.

  20. Theoretical investigation of the gas-phase reactions of CrO(+) with ethylene.

    PubMed

    Scupp, Thomas M; Dudley, Timothy J

    2010-01-21

    The potential energy surfaces associated with the reactions of chromium oxide cation (CrO(+)) with ethylene have been characterized using density functional, coupled-cluster, and multireference methods. Our calculations show that the most probable reaction involves the formation of acetaldehyde and Cr(+) via a hydride transfer involving the metal center. Our calculations support previous experimental hypotheses that a four-membered ring intermediate plays an important role in the reactivity of the system. We have also characterized a number of viable reaction pathways that lead to other products, including ethylene oxide. Due to the experimental observation that CrO(+) can activate carbon-carbon bonds, a reaction pathway involving C-C bond cleavage has also been characterized. Since many of the reactions involve a change in the spin state in going from reactants to products, locations of these spin surface crossings are presented and discussed. The applicability of methods based on Hartree-Fock orbitals is also discussed.

  1. Cocaine, Appetitive Memory and Neural Connectivity

    PubMed Central

    Ray, Suchismita

    2013-01-01

    This review examines existing cognitive experimental and brain imaging research related to cocaine addiction. In section 1, previous studies that have examined cognitive processes, such as implicit and explicit memory processes in cocaine users are reported. Next, in section 2, brain imaging studies are reported that have used chronic users of cocaine as study participants. In section 3, several conclusions are drawn. They are: (a) in cognitive experimental literature, no study has examined both implicit and explicit memory processes involving cocaine related visual information in the same cocaine user, (b) neural mechanisms underlying implicit and explicit memory processes for cocaine-related visual cues have not been directly investigated in cocaine users in the imaging literature, and (c) none of the previous imaging studies has examined connectivity between the memory system and craving system in the brain of chronic users of cocaine. Finally, future directions in the field of cocaine addiction are suggested. PMID:25009766

  2. Shock treatment: using immersive digital realism to restage and re-examine milgram's 'obedience to authority' research.

    PubMed

    Haslam, S Alexander; Reicher, Stephen D; Millard, Kathryn

    2015-01-01

    Attempts to revisit Milgram's 'Obedience to Authority' (OtA) paradigm present serious ethical challenges. In recent years new paradigms have been developed to circumvent these challenges but none involve using Milgram's own procedures and asking naïve participants to deliver the maximum level of shock. This was achieved in the present research by using Immersive Digital Realism (IDR) to revisit the OtA paradigm. IDR is a dramatic method that involves a director collaborating with professional actors to develop characters, the strategic withholding of contextual information, and immersion in a real-world environment. 14 actors took part in an IDR study in which they were assigned to conditions that restaged Milgrams's New Baseline ('Coronary') condition and four other variants. Post-experimental interviews also assessed participants' identification with Experimenter and Learner. Participants' behaviour closely resembled that observed in Milgram's original research. In particular, this was evidenced by (a) all being willing to administer shocks greater than 150 volts, (b) near-universal refusal to continue after being told by the Experimenter that "you have no other choice, you must continue" (Milgram's fourth prod and the one most resembling an order), and (c) a strong correlation between the maximum level of shock that participants administered and the mean maximum shock delivered in the corresponding variant in Milgram's own research. Consistent with an engaged follower account, relative identification with the Experimenter (vs. the Learner) was also a good predictor of the maximum shock that participants administered.

  3. Could Sodium Chloride be an Environmental Trigger for Immune-Mediated Diseases? An Overview of the Experimental and Clinical Evidence

    PubMed Central

    Toussirot, Eric; Béreau, Matthieu; Vauchy, Charline; Saas, Philippe

    2018-01-01

    Immune mediated diseases (IMDs) are complex chronic inflammatory diseases involving genetic and environmental factors. Salt intake has been proposed as a diet factor that can influence the immune response. Indeed, experimental data report the influence of sodium chloride on the differentiation of naive CD4+ T cells into IL-17 secreting T helper (Th) cells (Th17 cells), by a mechanism involving the serum glucocorticoid kinase-1 (SGK1) that promotes the expression of the IL-23 receptor (IL-23R). The IL-23/IL-23R is critical for pathogenic inflammatory Th17 cell differentiation. Experimental data in murine models of arthritis, colitis and encephalomyelitis corroborate these findings. This manuscript reviews the current knowledge on the effects of sodium chloride on innate and adaptive immunity. We also performed a systematic literature review for clinical studies examining the relationships between salt consumption and the development or the activity/severity of the most common IMDs mediated by the IL-23/Th17 pathway, i.e., rheumatoid arthritis (RA), multiple sclerosis (MS), and Crohn's disease (CD). Nine studies were found, 4 in RA, 4 in MS and 1 in CD. An association was found between developments of anti-citrullinated protein antibody (ACPA) positive RA in smokers and salt intake, but these results were not confirmed in another study. For MS, no association was observed in pediatric subjects while in adult patients, a link was found between salt intake and disease activity. However, this result was not confirmed in another study. These conflicting results highlight the fact that further evaluation in human IMDs is required. Moreover, physicians need to develop clinical trials with diet interventions to evaluate the impact of low salt intake on disease activity/severity of IMDs. PMID:29740348

  4. Could Sodium Chloride be an Environmental Trigger for Immune-Mediated Diseases? An Overview of the Experimental and Clinical Evidence.

    PubMed

    Toussirot, Eric; Béreau, Matthieu; Vauchy, Charline; Saas, Philippe

    2018-01-01

    Immune mediated diseases (IMDs) are complex chronic inflammatory diseases involving genetic and environmental factors. Salt intake has been proposed as a diet factor that can influence the immune response. Indeed, experimental data report the influence of sodium chloride on the differentiation of naive CD4 + T cells into IL-17 secreting T helper (Th) cells (Th17 cells), by a mechanism involving the serum glucocorticoid kinase-1 (SGK1) that promotes the expression of the IL-23 receptor (IL-23R). The IL-23/IL-23R is critical for pathogenic inflammatory Th17 cell differentiation. Experimental data in murine models of arthritis, colitis and encephalomyelitis corroborate these findings. This manuscript reviews the current knowledge on the effects of sodium chloride on innate and adaptive immunity. We also performed a systematic literature review for clinical studies examining the relationships between salt consumption and the development or the activity/severity of the most common IMDs mediated by the IL-23/Th17 pathway, i.e., rheumatoid arthritis (RA), multiple sclerosis (MS), and Crohn's disease (CD). Nine studies were found, 4 in RA, 4 in MS and 1 in CD. An association was found between developments of anti-citrullinated protein antibody (ACPA) positive RA in smokers and salt intake, but these results were not confirmed in another study. For MS, no association was observed in pediatric subjects while in adult patients, a link was found between salt intake and disease activity. However, this result was not confirmed in another study. These conflicting results highlight the fact that further evaluation in human IMDs is required. Moreover, physicians need to develop clinical trials with diet interventions to evaluate the impact of low salt intake on disease activity/severity of IMDs.

  5. Heart involvement in cystic fibrosis: A specific cystic fibrosis-related myocardial changes?

    PubMed

    Labombarda, Fabien; Saloux, Eric; Brouard, Jacques; Bergot, Emmanuel; Milliez, Paul

    2016-09-01

    Cystic fibrosis is a complex multi-systemic chronic disease characterized by progressive organ dysfunction with development of fibrosis, possibly affecting the heart. Over the last four decades pathological, experimental, and clinical evidence points towards the existence of a specific myocardial involvement in cystic fibrosis. Multi-modality cardiac imaging, especially recent echocardiographic techniques, evidenced diastolic and/or systolic ventricular dysfunction in cystic fibrosis leading to the concept of a cystic fibrosis-related cardiomyopathy. Hypoxemia and inflammation are among the most important factors for heart involvement in cystic fibrosis. Cystic Fibrosis Transmembrane Regulator was found to be involved in the regulation of cardiomyocyte contraction and may also account for cystic fibrosis-related myocardial dysfunction. This review, mainly focused on echocardiographic studies, seeks to synthesize the existing literature for and against the existence of heart involvement in cystic fibrosis, its mechanisms and prognostic implications. Careful investigation of the heart function may be helpful for risk stratification and therapeutic decisions in patients with cystic fibrosis. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. The effect of recovery coaches for substance-involved mothers in child welfare: impact on juvenile delinquency.

    PubMed

    Douglas-Siegel, Jonah A; Ryan, Joseph P

    2013-10-01

    Despite the documented relationship between parental substance abuse and youth delinquency, the effects of parental interventions on delinquency outcomes are unknown. Such interventions are particularly vital for families in the child welfare system who are at heightened risk for both parental substance involvement and youth delinquency. The current study tested the impact of intensive case management in the form of a recovery coach for substance-involved mothers on youth delinquency outcomes among a randomized sample of 453 families involved in a Title IV-E experimental waiver demonstration in Cook County, Illinois. In comparison to control group participants, families enrolled in the Alcohol and Other Drug Abuse (AODA) waiver demonstration experienced a lower rate of juvenile arrest, net of factors such as demographic characteristics, primary drug of choice, and time spent in substitute care. Findings support efforts to curb delinquency among child-welfare involved youth by providing recovery coaches to their substance abusing or dependent parents. © 2013.

  7. Transport of fluorobenzoate tracers in a vegetated hydrologic control volume: 1. Experimental results

    NASA Astrophysics Data System (ADS)

    Queloz, Pierre; Bertuzzo, Enrico; Carraro, Luca; Botter, Gianluca; Miglietta, Franco; Rao, P. S. C.; Rinaldo, Andrea

    2015-04-01

    This paper reports about the experimental evidence collected on the transport of five fluorobenzoate tracers injected under controlled conditions in a vegetated hydrologic volume, a large lysimeter (fitted with load cells, sampling ports, and an underground chamber) where two willows prompting large evapotranspiration fluxes had been grown. The relevance of the study lies in the direct and indirect measures of the ways in which hydrologic fluxes, in this case, evapotranspiration from the upper surface and discharge from the bottom drainage, sample water and solutes in storage at different times under variable hydrologic forcings. Methods involve the accurate control of hydrologic inputs and outputs and a large number of suitable chemical analyses of water samples in discharge waters. Mass extraction from biomass has also been performed ex post. The results of the 2 year long experiment established that our initial premises on the tracers' behavior, known to be sorption-free under saturated conditions which we verified in column leaching tests, were unsuitable as large differences in mass recovery appeared. Issues on reactivity thus arose and were addressed in the paper, in this case attributed to microbial degradation and solute plant uptake. Our results suggest previously unknown features of fluorobenzoate compounds as hydrologic tracers, potentially interesting for catchment studies owing to their suitability for distinguishable multiple injections, and an outlook on direct experimental closures of mass balance in hydrologic transport volumes involving fluxes that are likely to sample differently stored water and solutes.

  8. Theoretical study of the electronic and optical properties of photochromic dithienylethene derivatives connected to small gold clusters.

    PubMed

    Perrier, Aurélie; Maurel, François; Aubard, Jean

    2007-10-04

    In the course of developing electronic devices on a molecular scale, dithienylethenes photochromic molecules constitute promising candidates for optoelectronic applications such as memories and switches. There is thus a great interest to understand and control the switching behavior of photochromic compounds deposited on metallic surfaces or nanoparticles. Within the framework of the density functional theory, we studied the effect of small gold clusters (Au3 and Au9) on the electronic structure and absorption spectrum of a model dithienylethene molecule. The molecular orbital interactions between the photochromic molecule and the gold cluster made it possible to rationalize some experimental findings (Dulic, D.; van der Molen, S. J.; Kudernac, T.; Jonkman, H. T.; de Jong, J. J. D.; Bowden, T. N.; van Esch, J.; Feringa, B. L.; van Wees, B. J. Phys. Rev. Lett. 2003, 91, 207402). For the closed-ring isomer, grafting a photochromic molecule on a small gold cluster does not change the characteristics of the electronic transition involved in the ring-opening reaction. On the opposite, the absorption spectrum of the photochromic open-ring isomer is strongly modified by the inclusion of the metallic cluster. In agreement with experimental results, our study thus showed that the cycloreversion reaction which involves the closed-ring isomer should be still possible, whereas the ring-closure reaction which involves the open-ring isomer should be inhibited. Connecting a dithienylethene molecule to a small gold cluster hence provides a qualitative comprehension of the photochromic activities of dithienylethenes connected to a gold surface.

  9. Development of Laboratory Investigations in Disorders of Sex Development.

    PubMed

    Audí, Laura; Camats, Núria; Fernández-Cancio, Mónica; Granada, María L

    2018-01-01

    Scientific knowledge to understand the biological basis of sex development was prompted by the observation of variants different from the 2 most frequent body types, and this became one of the fields first studied by modern pediatric endocrinology. The clinical observation was supported by professionals working in different areas of laboratory sciences which led to the description of adrenal and gonadal steroidogenesis, the enzymes involved, and the different deficiencies. Steroid hormone measurements evolved from colorimetry to radioimmunoassay (RIA) and automated immunoassays, although gas and liquid chromatography coupled to mass spectrometry are now the gold standard techniques for steroid measurements. Peptide hormones and growth factors were purified, and their measurement evolved from RIA to automated immunoassays. Hormone action mechanisms were described, and their specific receptors were characterized and assayed in experimental materials and in patient tissues and cell cultures. The discovery of the genetic basis for variant sex developments began with the description of the sex chromosomes. Molecular technology allowed cloning of genes coding for the different proteins involved in sex determination and development. Experimental animal models aided in verifying the roles of proteins and also suggested new genes to be investigated. New candidate genes continue to be described based on experimental models and on next-generation sequencing of patient DNAs. © 2017 S. Karger AG, Basel.

  10. Integration of biological data by kernels on graph nodes allows prediction of new genes involved in mitotic chromosome condensation

    PubMed Central

    Hériché, Jean-Karim; Lees, Jon G.; Morilla, Ian; Walter, Thomas; Petrova, Boryana; Roberti, M. Julia; Hossain, M. Julius; Adler, Priit; Fernández, José M.; Krallinger, Martin; Haering, Christian H.; Vilo, Jaak; Valencia, Alfonso; Ranea, Juan A.; Orengo, Christine; Ellenberg, Jan

    2014-01-01

    The advent of genome-wide RNA interference (RNAi)–based screens puts us in the position to identify genes for all functions human cells carry out. However, for many functions, assay complexity and cost make genome-scale knockdown experiments impossible. Methods to predict genes required for cell functions are therefore needed to focus RNAi screens from the whole genome on the most likely candidates. Although different bioinformatics tools for gene function prediction exist, they lack experimental validation and are therefore rarely used by experimentalists. To address this, we developed an effective computational gene selection strategy that represents public data about genes as graphs and then analyzes these graphs using kernels on graph nodes to predict functional relationships. To demonstrate its performance, we predicted human genes required for a poorly understood cellular function—mitotic chromosome condensation—and experimentally validated the top 100 candidates with a focused RNAi screen by automated microscopy. Quantitative analysis of the images demonstrated that the candidates were indeed strongly enriched in condensation genes, including the discovery of several new factors. By combining bioinformatics prediction with experimental validation, our study shows that kernels on graph nodes are powerful tools to integrate public biological data and predict genes involved in cellular functions of interest. PMID:24943848

  11. Simultaneous determination of apparent tortuosity and microstructure length scale and shape: Application to rigid open cell foams

    NASA Astrophysics Data System (ADS)

    Gómez Álvarez-Arenas, T. E.; de la Fuente, S.; González Gómez, I.

    2006-05-01

    A novel experimental technique based on phase spectroscopy and through transmission of high-frequency airborne ultrasonic pulses is used to study rigid open cell foams. Phase velocity shows an anomalous relaxation like behavior which is attributed to a frequency variation of the apparent tortuosity. An explanation is proposed in terms of the relationship between the different length scales involved: microstructure and macroscopic behavior. The experimental technique together with the proposed apparent tortuosity scheme provides a novel and unique procedure to determine simultaneously tortuosity and characteristic length dimension and shape of the solid constituent of foams and porous materials in general.

  12. Static strain and vibration characteristics of a metal semimonocoque helicopter tail cone of moderate size

    NASA Technical Reports Server (NTRS)

    Bielawa, Richard L.; Hefner, Rachel E.; Castagna, Andre

    1991-01-01

    The results are presented of an analytic and experimental research program involving a Sikorsky S-55 helicopter tail cone directed ultimately to the improved structural analysis of airframe substructures typical of moderate sized helicopters of metal semimonocoque construction. Experimental static strain and dynamic shake-testing measurements are presented. Correlation studies of each of these tests with a PC-based finite element analysis (COSMOS/M) are described. The tests included static loadings at the end of the tail cone supported in the cantilever configuration as well as vibrational shake-testing in both the cantilever and free-free configurations.

  13. Sensor-Based Human Activity Recognition in a Multi-user Scenario

    NASA Astrophysics Data System (ADS)

    Wang, Liang; Gu, Tao; Tao, Xianping; Lu, Jian

    Existing work on sensor-based activity recognition focuses mainly on single-user activities. However, in real life, activities are often performed by multiple users involving interactions between them. In this paper, we propose Coupled Hidden Markov Models (CHMMs) to recognize multi-user activities from sensor readings in a smart home environment. We develop a multimodal sensing platform and present a theoretical framework to recognize both single-user and multi-user activities. We conduct our trace collection done in a smart home, and evaluate our framework through experimental studies. Our experimental result shows that we achieve an average accuracy of 85.46% with CHMMs.

  14. Expression-invariant representations of faces.

    PubMed

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

    2007-01-01

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

  15. Experimental Greenberger-Horne-Zeilinger-Type Six-Photon Quantum Nonlocality.

    PubMed

    Zhang, Chao; Huang, Yun-Feng; Wang, Zhao; Liu, Bi-Heng; Li, Chuan-Feng; Guo, Guang-Can

    2015-12-31

    Quantum nonlocality gives us deeper insight into quantum physics. In addition, quantum nonlocality has been further recognized as an essential resource for device-independent quantum information processing in recent years. Most experiments of nonlocality are performed using a photonic system. However, until now, photonic experiments of nonlocality have involved at most four photons. Here, for the first time, we experimentally demonstrate the six-photon quantum nonlocality in an all-versus-nothing manner based on a high-fidelity (88.4%) six-photon Greenberger-Horne-Zeilinger state. Our experiment pushes multiphoton nonlocality studies forward to the six-photon region and might provide a larger photonic system for device-independent quantum information protocols.

  16. Experimental observation of complete and anticipation synchronization of heterogeneous oscillators using a common dynamical environment

    NASA Astrophysics Data System (ADS)

    Singla, Tanu; Chandrasekhar, E.; Singh, B. P.; Parmananda, P.

    2014-12-01

    Complete and anticipation synchronization of nonlinear oscillators from different origins is attempted experimentally. This involves coupling these heterogeneous oscillators to a common dynamical environment. Initially, this phenomenon was studied using two parameter mismatched Chua circuits. Subsequently, three different timeseries: a) x variable of the Lorenz oscillator b) the X-component of Earth's magnetic field and c) per-day temperature variation of the Region Santa Cruz in Mumbai, India are environmentally coupled, under the master-slave scenario, with a Chua circuit. Our results indicate that environmental coupling is a potent tool to provoke complete and anticipation synchronization of heterogeneous oscillators from distinct origins.

  17. A conceptual design study of the reusable reentry satellite

    NASA Technical Reports Server (NTRS)

    Swenson, Byron L.; Mascy, Alfred C.; Carter, Bruce; Cartledge, Alan; Corridan, Robert E.; Edsinger, Larry E.; Jackson, Robert W.; Keller, Robert; Murbach, Marcus S.; Wercinski, Paul F.

    1988-01-01

    Experimentation leading to an understanding of life processes under reduced and extremely low gravitational forces will profoundly contribute to the success of future space missions involving humans. In addition to research on gravitational biology, research on the effects of cosmic radiation and the interruption and change of circadian rhythms on life systems is also of prime importance. Research in space, however, is currently viewed by biological scientists as an arena that is essential, yet largely inaccessible to them for their experimentation. To fulfill this need, a project and spacecraft system described as the Reusuable Reentry Satellite or Lifesat has been proposed by NASA.

  18. 77 FR 27054 - Wolbachia pipientis;

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-08

    ... Experimental Use Permit; Receipt of Application; Comment Request AGENCY: Environmental Protection Agency (EPA... University of Kentucky, Department of Entomology requesting an experimental use permit (EUP) for the... environmental justice, the fair treatment and meaningful involvement of any group, including minority and/or low...

  19. Musk as a Pheromone? Didactic Exercise.

    ERIC Educational Resources Information Center

    Bersted, Chris T.

    A classroom/laboratory exercise has been used to introduce college students to factorial research designs, differentiate between interpretations for experimental and quasi-experimental variables, and exemplify application of laboratory research methods to test practical questions (advertising claims). The exercise involves having randomly divided…

  20. Experimental Lung Cancer Drug Shows Early Promise | Poster

    Cancer.gov

    By Frank Blanchard, Staff Writer A first-of-its-kind drug is showing early promise in attacking certain lung cancers that are hard to treat because they build up resistance to conventional chemotherapy. The drug, CO-1686, performed well in a preclinical study involving xenograft and transgenic mice, as reported in the journal Cancer Discovery. It is now being evaluated for

Top