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Sample records for quantitative bibliometric study

  1. An Expanding and Shifting Focus in Recent Environmental Health Literature: A Quantitative Bibliometric Study.

    PubMed

    Mao, Guozhu; Liu, Xi; Du, Huibin; Zuo, Jian; Li, Na

    2016-01-01

    This special report characterizes the patterns of environmental health literature from 1993 to 2012 by using bibliometric techniques based on databases of the Science Citation Index and the Social Science Citation Index. "Research article" was the most widely used document type, accounting for 71.7% of the total records (5,053), and 94.9% of these articles were published in English. The number of environmental health publications is growing along with an increasing level of communication. The U.S. was the largest contributing country with the highest h-index (85) and the most publications (1,854), followed by the UK and Canada. Environmental Health Perspectives and the Journal of Environmental Health were the top two most productive journals. The most cited article in each main research area is also listed. The authors' study not only identifies global characteristics in environmental health research, but also influences researchers' selection of future studies and publications. PMID:26867292

  2. Weak interactions from 1950-1960: a quantitative bibliometric study of the formation of a field

    SciTech Connect

    White, D.H.; Sullivan, D.

    1986-01-01

    A quantitative technique is illustrated which uses publication statistics from a bibliography of citations in the area of weak interactions to provide a view of trends and patterns in the development of the field during the period from 1950 to 1960. An overview is given of what the physicists working in weak interactions during this period were doing as indicated by an analysis of the subjects of their papers. The dominant problems and concerns are discussed. Focus is then turned to the events surrounding the emergence of the tau/theta particle puzzle, the discovery of parity nonconservation, and the resolution offered by the V-A theory. Displaying the data from the citation index in unusual ways highlights dominant issues of the period, especially the close relationship between theory and experiment in the latter half of the decade. 64 refs., 14 figs. (LEW)

  3. Combining Mapping and Citation Analysis for Evaluative Bibliometric Purposes: A Bibliometric Study.

    ERIC Educational Resources Information Center

    Noyons, E. C. M; Moed, H. F.; Luwel, M.

    1999-01-01

    Presents the results of a combined performance/mapping study used to evaluate a Belgian research institute in microelectronics. Results from one bibliometric approach were used to validate results of another. Findings indicated that the method provides a detailed and useful picture of the position of the institute from an international…

  4. Bibliometric Techniques Applied to Issues Management: A Case Study.

    ERIC Educational Resources Information Center

    Lancaster, F. W.; Lee, Ja-Lih

    1985-01-01

    Case study on acid rain illustrates procedures for systematized tracking of issues: using bibliometric methods to list journals to be scanned; using current awareness searches of online databases to supplement journal scanning; using literature monitoring to create significant terms file; and tracking terms through online database index. (10…

  5. An Outline of Bibliometrics and Citation Analysis.

    ERIC Educational Resources Information Center

    Hjerppe, Roland

    Quantitative analysis of scientific literature and especially citation networks have been used to illuminate many aspects of science and research. These studies, formally called statistical bibliography, are now described by the term bibliometrics. This paper provides a survey of bibliometrics including a set of necessary definitions, the scope…

  6. Bibliometric study of the quality of celiac disease research publications.

    PubMed

    Master, Samuel; Lebwohl, Benjamin; Ludvigsson, Jonas F; Green, Peter H

    2013-10-01

    Celiac disease (CD) is common and occurs in both children and adults. A recent bibliometric study revealed that the journal with the most CD articles was the Journal of Pediatric Gastroenterology and Nutrition followed by the American Journal of Gastroenterology, a journal predominantly concerned with adult issues. To assess the quality and complexity of CD, research appearing in these journals used strict published criteria to assess the quality of the research in the 30 most recent research articles in each journal. The authors found that the research reported in these articles was of similar high quality and complexity. PMID:23838822

  7. Informetrics - A New Area of Quantitative Studies.

    ERIC Educational Resources Information Center

    Wormell, Irene

    2000-01-01

    Describes the merging field of informetrics in a historical perspective as a generalization of bibliometrics, combining advanced information retrieval theories and methodologies with the quantitative study of information flow. Explains programs at the Center for Information Studies at the Royal School of Library and Information Science in…

  8. The Bibliometric Analysis Of Literature On Museum Studies

    NASA Astrophysics Data System (ADS)

    Kuo, C. W.; Yang, Y. H.

    2015-08-01

    Museum studies, is the study of museums, museum curation, and how and why museums developed into their institutional role in education and culture through scientific, social, political and other related forces. The purpose of this study is to shed light on the application trends of the international literature related to museum studies on the SCIE, SSCI, and AHCI databases between 1995 and 2014 using a bibliometric technique and citation analysis. The results of this study reveal that influences of the literature related to museum studies on other subject areas continue to expand. Considering the publication of major countries, subject areas, journal and institutions, the results also discussed that the future trend through analysing most cited articles. Moreover, 12 core journal lists are identified by Bradford's law.

  9. International journal of mental health systems: a bibliometric study

    PubMed Central

    2014-01-01

    Background The International Journal of Mental Health Systems (IJMHS) was launched in August 2007 and has recently been given a formal impact factor. This study uses bibliometric indicators to review the performance of the Journal against its original stated objectives and aspirations. Methods All articles published in IJMHS since publication commenced were included (n = 158). Selected bibliometric measures indicating Journal productivity, author affiliation, impact, geographic reach, and international collaboration were utilised. Results IJMHS published 158 articles in seven volumes over six years. Articles with three to five authors constitute the dominant authorship pattern, and authors’ affiliations are varied. IJMHS has received an impact factor of 1.06 from Thomson Reuters, and the SCImago Journal Ranking shows IJMHS to be well positioned in the four categories in which it is listed, including in comparisons with well-established BMC journals that have similar scientific interests. Geographic authorship patterns show contributions from a large number of countries, including many low- and middle-income countries. Discussion Manuscript submissions from a wide range of countries, including low- and middle-income countries, are mostly from academic institutions. Authors from some geographic areas of the world are significantly under-represented. The calculation of an impact factor and encouraging rankings on the SCImago Journal Rank index are expected to lead to increased submission of high quality manuscripts. Conclusion The performance of IJMHS over the first six years is promising, and the Journal is on the way to achieving the aims set out in the inaugural Editorial. IJMHS will continue to enhance its current impact through a number of new initiatives, including the introduction of thematic series and a broader range of article categories. PMID:24393301

  10. Examining semantics in interprofessional research: A bibliometric study.

    PubMed

    Perrier, Laure; Adhihetty, Chamila; Soobiah, Charlene

    2016-05-01

    While experts in the field provide clarity between terms such as interprofessional and multidisciplinary, the published literature may not be offering this preciseness. A bibliometric analysis was conducted on 1,148 studies that examined terms such as interprofessional, multidisciplinary, and teamwork in order to examine patterns of indexing, overlap in how terms and phrases are used by authors, and consistencies in the definitions of terminology. A small number of relevant indexing terms are available in PubMed but were not regularly applied to the studies in this subject area. Our findings indicate that relying on indexing terms to locate this body of literature will not reliably identify all relevant studies when searching the literature. Definitions for these terms were typically not offered by authors, references were not regularly provided when definitions were included, and clear distinctions between the different terms were not reliably provided, thus creating further difficulties. Poor indexing, lack of consistent definitions being used in the research literature, and some authors using phrases and terms as synonyms make it challenging for educators, scholars, and researchers to search, find, and use this body of literature. PMID:27152531

  11. Disciplinary and Research Subjects in French Doctoral Dissertations in Press and Media Studies: A Bibliometric Treatment

    ERIC Educational Resources Information Center

    Herubel, Jean-Pierre V. M.

    2007-01-01

    For English-speaking researchers, French doctoral dissertations can represent a "terra incognita." For this reason, a retrospective bibliometric study of French dissertations in press and media studies offers a useful profile of available research to researchers concentrating in studies of the press and other media. The present study offers a…

  12. Professional Competencies and Jurisdictional Claims in Evaluative Bibliometrics: The Educational Mandate of Academic Librarians

    ERIC Educational Resources Information Center

    Petersohn, Sabrina

    2016-01-01

    Quantitative metrics in research assessment are proliferating all over the world. The demand has led to an increase in bibliometric practitioners and service providers. Their professional roles and competencies have not yet been subject to systematic study. This paper focuses on one important service provider in evaluative bibliometrics--academic…

  13. A Bibliometric Study of the "Journal of Education for Librarianship," 1960-1984. Full Report.

    ERIC Educational Resources Information Center

    Schrader, Alvin M.

    This study describes and evaluates key bibliometric patterns in the articles published by the former "Journal of Education for Librarianship" (JEL) during its first 24 volumes of existence from 1960 to 1984. Data from each issue of JEL were collected and analyzed using a statistical analysis software package, SPSSx (Statistical Package for the…

  14. Quo Vadis Clozapine? A Bibliometric Study of 45 Years of Research in International Context

    PubMed Central

    López-Muñoz, Francisco; Sanz-Fuentenebro, Javier; Rubio, Gabriel; García-García, Pilar; Álamo, Cecilio

    2015-01-01

    We have carried out a bibliometric study about the international scientific publications on clozapine. We have used the EMBASE and MEDLINE databases, and we applied bibliometric indicators of production, as Price’s Law on the increase of scientific literature. We also calculated the participation index (PI) of the different countries. The bibliometric data have also been correlated with some social and health data from the 12 most productive countries in biomedicine and health sciences. In addition, 5607 original documents dealing with clozapine, published between 1970 and 2013, were downloaded. Our results state non-fulfilment of Price’s Law, with scientific production on clozapine showing linear growth (r = 0.8691, vs. r = 0.8478 after exponential adjustment). Seven of the 12 journals with the highest numbers of publications on clozapine have an Impact Factor > 2. Among the countries generating clozapine research, the most prominent is the USA (PI = 24.32), followed by the UK (PI = 6.27) and Germany (PI = 5.40). The differences among countries on clozapine research are significantly related to economic variables linked to research. The scientific interest in clozapine remains remarkable, although after the application of bibliometric indicators of production, a saturation point is evident in the growth of scientific literature on this topic. PMID:26404263

  15. Academic Impact of Qualitative Studies in Healthcare: Bibliometric Analysis

    PubMed Central

    Mori, Hiroko; Nakayama, Takeo

    2013-01-01

    Context Although qualitative studies are becoming more appreciated in healthcare, the number of publications of quality studies remains low. Little is known about the frequency and characteristics of citation in qualitative studies. Objective To compare the academic impact of qualitative studies to that of two quantitative studies: systematic reviews and randomized controlled trials. Methods Publications in BMJ between 1997 and 2006 (BMJ’s median impact factor was 7.04 during this period) employing qualitative methods were matched to two quantitative studies appearing the same year using PubMed. Using Web of Science, citations within a 24-month publication period were determined. Additionally, three hypotheses were examined: qualitative studies are 1) infrequently cited in original articles or reviews; 2) rarely cited by authors in non-English-speaking countries; and 3) more frequently cited in non-medical disciplines (e.g., psychology or sociology). Results A total of 121 qualitative studies, 270 systematic reviews, and 515 randomised controlled trials were retrieved. Qualitative studies were cited a total of 1,089 times, with a median of 7.00 times (range, 0–34) for each study. Matched systematic reviews and randomized controlled trials were cited 2,411times and 1,600 times, respectively. With respect to citing documents, original articles and reviews exceeded 60% for each study design. Relative to quantitative studies, qualitative studies were cited more often by authors in English-speaking countries. With respect to subject area, medical disciplines were more frequently cited than non-medical disciplines for all three study designs (>80%). Conclusion The median number of citations for qualitative studies was almost the same as the median of BMJ’s impact factor during the survey period. For a suitable evaluation of qualitative studies in healthcare, it will be necessary to develop a reporting framework and include explicit discussions of clinical

  16. Telescope Bibliometrics 101

    NASA Astrophysics Data System (ADS)

    Grothkopf, Uta; Lagerstrom, Jill

    During recent years, bibliometric studies have become increasingly important in evaluating individual scientists, institutes, and entire observatories. In astronomy, often librarians are involved in maintaining publication databases and compiling statistics for their institutions. In this paper, we present a look behind the scenes to understand who is interested in bibliometric statistics, which methodologies astronomy librarians apply, and what kind of features next-generation bibliographies may include.

  17. A Bibliometric Study to Manage a Journal Collection in an Astronomical Library: Some Results

    NASA Astrophysics Data System (ADS)

    Gomez, Monique

    The evaluation of the use of library collections is a fundamental tool for the development of a relevant and cost-effective collection. Bibliometrics offers several methods to measure the level of use of collections. In this paper, we present the first results of a bibliometric analysis of the references cited in the articles published by authors of the Instituto de Astrofísica de Canarias during the last decade. We have determined which kinds of publications and which journals are mainly used. We also have studied the ages of the cited journals and their cost-effectiveness. Additionally, to see if the advent of the WWW in the mid 1990s has influenced the reading or citing practices of the authors, we have compared two sets of data: articles published over the period 1991--3 that we define as the pre-WWW period and articles published over the period 1997--9 defined as the WWW period.

  18. Bibliometrics, Librarians, and Bibliograms

    ERIC Educational Resources Information Center

    White, Howard D.

    2016-01-01

    This paper sets forth an integrated way of introducing bibliometrics to relatively non-quantitative audiences, such as librarians and iSchool students. The integrative device is the bibliogram, a linguistic object consisting of a seed term and the terms that co-occur with it, ranked by their co-occurrence counts with the seed--a standard…

  19. A bibliometric study of scientific research conducted on second-generation antipsychotic drugs in Singapore

    PubMed Central

    López-Muñoz, Francisco; Sim, Kang; Shen, Winston Wu; Huelves, Lorena; Moreno, Raquel; Molina, Juan de Dios; Rubio, Gabriel; Noriega, Concha; Ángel Miguel, Pérez-Nieto; Álamo, Cecilio

    2014-01-01

    INTRODUCTION A bibliometric study was carried out to ascertain the volume and impact of scientific literature published on second-generation antipsychotic drugs (SGAs) in Singapore from 1997 to 2011. METHODS A search of the EMBASE and MEDLINE databases was performed to identify articles originating from Singapore that included the descriptors ‘atypic* antipsychotic*’, ‘second-generation antipsychotic*’, ‘clozapine’, ‘risperidone’, ‘olanzapine’, ‘ziprasidone’, ‘quetiapine’, ‘sertindole’, ‘aripiprazole’, ‘paliperidone’, ‘amisulpride’, ‘zotepine’, ‘asenapine’, ‘iloperidone’, ‘lurasidone’, ‘perospirone’ and ‘blonanserin’ in the article titles. Certain bibliometric indicators of production and dispersion (e.g. Price's Law on the increase of scientific literature, and Bradford's Law) were applied, and the participation index of various countries was calculated. The bibliometric data was also correlated with some social and health data from Singapore, such as the total per capita expenditure on health and gross domestic expenditure on research and development. RESULTS From 1997 to 2011, a total of 51 articles on SGAs in Singapore were published. Our results suggested non-fulfilment of Price's Law (r = 0.0648 after exponential adjustment vs. r = 0.2140 after linear adjustment). The most widely studied drugs were clozapine (21 articles), risperidone (16 articles) and olanzapine (8 articles). Division into Bradford zones yielded a nucleus occupied by the Journal of Clinical Psychopharmacology (6 articles) and the Singapore Medical Journal (4 articles). The analysed material was published in a total of 30 journals, with the majority from six journals. Four of these six journals have an impact factor greater than 2. CONCLUSION Publications on SGAs in Singapore are still too few to confirm an exponential growth of scientific literature. PMID:24452974

  20. Developing Comparative Bibliometric Indicators for Evaluating the Research Performance of Four Academic Nutrition Departments, 1992-1996: An Exploratory Study.

    ERIC Educational Resources Information Center

    Ackermann, Eric George

    This study develops a set of empirically and theoretically sound citation-based bibliometric indicators of scientific research performance and applies them in an exploratory comparative study of the University of Tennessee-Knoxville's (UTK's) Nutrition Department with three of its peer programs at the University of Florida, the University of…

  1. [Research on quality of health care from the Mexican Social Security Institute: a bibliometric study].

    PubMed

    Navarrete-Navarro, Susana; Gómez-Delgado, Alejandro; Riebeling-Navarro, Carlos; López-García, Gloria Araceli; Nava-Zavala, Arnulfo

    2013-12-01

    OBJECTIVE. To identify studies on quality of health care in the IMSS. MATERIALS AND METHODS. A bibliometric, descriptive cross-sectional and retrospective study was conducted, from 1992 to 2011. RESULTS. We identified 881 research studies related to the issue of quality (CI95% 10.6-12.0) of 7 762 studies presented at the annual research meetings. 10 521 articles were published in this period of time and only 946 (CI95% 8.4-9.5) were linked to the issue of quality. CONCLUSIONS. The results of this study allowed us to identify the interest about research on quality. Further research is needed to establish what has been the impact on the improvement of quality in health care. PMID:24715009

  2. A bibliometric study of publications by Indian ophthalmologists and vision researchers, 2001-06

    PubMed Central

    Kumaragurupari, R; Sieving, Pamela C; Lalitha, Prajna

    2010-01-01

    Objective: The objective was to conduct a bibliometric analysis of Indian ophthalmic papers published from 2001 to 2006 in the peer-reviewed journals, to assess productivity, trends in journal choice, publication types, research funding, and collaborative research. Materials and Methods: We searched PubMed for articles indicating both vision-related content and author affiliation with an Indian research center. We identified research collaborations and funding from indexing for research support, and classified articles as reporting basic science, clinical science, or clinically descriptive research. Impact factors were determined from Journal Citation Reports for 2006. Results: The total number of published articles that were retrieved for the years 2001 to 2006 was 2163. During the six-year period studied, the annual output of research articles has nearly doubled, from 284 in 2001 to 460 in 2006. Two-thirds of these were published in international journals; 41% in vision-related journals with 2006 impact factors; and 3% in impact factor journals which were not vision-related. Fifty percent of the publications came from nine major eye hospitals. Clinical science articles were most frequently published whereas basic science the least. Publications resulting from international collaborations increased from 3% in 2001 to 8% in 2006. The focus of the journal with the highest number of publications corresponds to the most common cause of bilateral blindness in India, cataract. Conclusion: This bibliometric study of publications of research from India in the field of ophthalmic and vision research shows that research productivity, as measured in both the number of publications in peer-reviewed journals and qualitative measures of those journals, has increased during the period of this study. PMID:20534915

  3. A Bibliometric and Trend Analysis on the Water-Related Risk Assessment Studies for Cryptosporidium Pathogen

    PubMed Central

    MESDAGHINIA, Alireza; YOUNESIAN, Masuod; NASSERI, Simin; NABIZADEH NODEHI, Ramin; HADI, Mahdi

    2015-01-01

    Background: The bibliometric methods have been used in many disciplines of sciences to study the scientific production and research trends. In this study, they were used to investigate research trends related to the risk assessment of Cryptosporidium pathogen in water field. Methods: Data were obtained on the Scopus database from 1993 to 2013. Research tendency was investigated by analyzing the distribution of languages, countries, journals, author keywords, authorship pattern and co-authorship relations. Results: The English language was dominant language of all publications (96.36%). Number of articles in this field increased from 2 in 1993 to 29 papers in 2007 and then received to 19 at the end of 2013. United States produced 35.41% of all pertinent articles followed by United Kingdom with 10.76% and Australia with 9.92%. Water Research Journal published the most papers in this field, taking 11.62% of all, followed by Journal of Water and Health (10.92%) and Water Science and Technology (10.21%). The most productive authors were Ashbolt NJ form Canada that accounts about 1.51% of the total publications followed by Rose JB and Haas CN from United States. Authorship pattern analysis results show that literature does follow Lotka’s law (P=0.627). Conclusion: A downward trend in the number of publications is likely to occur in future. The results of this bibliometric analysis may help relevant researchers realize the scope of the microbial risk assessment research of Cryptosporidium, and establish the further research direction. PMID:26622289

  4. Community pharmacy-based research in Spain (1995-2005): A bibliometric study

    PubMed Central

    Andrés Iglesias, José Carlos; Andrés Rodríguez, N. Floro; Fornos Pérez, José Antonio

    Only one study evaluated the scientific activity in community pharmacies in Spain, and it was restricted to articles published in just two journals. Objective To assess the scientific activity in community pharmacies in Spain through a bibliometric analysis of the original papers published during the years 1995-2005. Methods IPA, MEDLINE, CSIC database and the journals Seguimiento Farmacoterapéutico y Pharmaceutical Care España were used as data sources. Production indicators, consumption indicators and the impact factor (IF) as a repercussion index were analyzed. Results 122 articles were included in the review. The articles were published in 12 journals, 78.7% of them in Pharmaceutical Care España and Seguimiento Farmacoterapéutico. The mean number of authors per article was 4.2 (SD=2.1). The transitivity index was 71.3%. The total number of references cited in the articles was 2110. The mean number of references per article was 17.3 SD=9.3. The value of the insularity index was 57.6%. Self citation was 6.8% and the Price index was 66.5%. No impact factor was available for 6 journals. Conclusions Publication of articles on community pharmacy-based research in Spain has undergone an important increase in the last 5 years. The existence of authors who publish very few studies, the high insularity index and the lack of randomized, controlled trials may be considered as negative indicators in community pharmacy-based research in Spain. PMID:25214914

  5. A Bibliometric Analysis of Climate Engineering Research

    NASA Astrophysics Data System (ADS)

    Belter, C. W.; Seidel, D. J.

    2013-12-01

    The past five years have seen a dramatic increase in the number of media and scientific publications on the topic of climate engineering, or geoengineering, and some scientists are increasingly calling for more research on climate engineering as a possible supplement to climate change mitigation and adaptation strategies. In this context, understanding the current state of climate engineering research can help inform policy discussions and guide future research directions. Bibliometric analysis - the quantitative analysis of publications - is particularly applicable to fields with large bodies of literature that are difficult to summarize by traditional review methods. The multidisciplinary nature of the published literature on climate engineering makes it an ideal candidate for bibliometric analysis. Publications on climate engineering are found to be relatively recent (more than half of all articles during 1988-2011 were published since 2008), include a higher than average percentage of non-research articles (30% compared with 8-15% in related scientific disciplines), and be predominately produced by countries located in the Northern Hemisphere and speaking English. The majority of this literature focuses on land-based methods of carbon sequestration, ocean iron fertilization, and solar radiation management and is produced with little collaboration among research groups. This study provides a summary of existing publications on climate engineering, a perspective on the scientific underpinnings of the global dialogue on climate engineering, and a baseline for quantitatively monitoring the development of climate engineering research in the future.

  6. Bibliometric analysis of scientific literature on intestinal parasites in Argentina during the period 1985-2014.

    PubMed

    Basualdo, Juan A; Grenóvero, María S; Bertucci, Evangelina; Molina, Nora B

    2016-01-01

    The study of scientific production is a good indicator of the progress in research and knowledge generation. Bibliometrics is a scientific discipline that uses a set of indicators to quantitatively express the bibliographic characteristics of scientific publications. The scientific literature on the epidemiology of intestinal parasites in Argentina is scattered in numerous sources, hindering access and visibility to the scientific community. Our purpose was to perform a quantitative, bibliometric study of the scientific literature on intestinal parasites in humans in Argentina published in the period 1985-2014. This bibliometric analysis showed an increase in the number of articles on intestinal parasites in humans in Argentina published over the past 30 years. Those articles showed a collaboration index similar to that of the literature, with a high index of institutionality for national institutions and a very low one for international collaboration. The original articles were published in scientific journals in the American Continent, Europe and Asia. The use of bibliometric indicators can provide a solid tool for the diagnosis and survey of the research on epidemiology of intestinal parasites and contributes to the dissemination and visibility of information on the scientific production developed in Argentina. PMID:27282076

  7. Bibliometrical Study of the Scientific Production and Citation of Dr. Guillermo Haro Barraza

    NASA Astrophysics Data System (ADS)

    Mata-Acosta, V.; Jiménez-Fragozo, M. E.; Figueroa-Servin, R. D.

    2010-10-01

    The main objective of this work is to characterize the bibliometric behavior of the scientific work of Dr. Guillermo Haro (March 21, 1913 - April 26, 1988). Professor Haro's scientific writings spanned from 1944 to 1988. In this paper, we consider citations made up until February 9, 2009. The methodology used is based on the creation of three databases. The first database is composed of a total of 93 articles with their publication data. The second database contains 710 references cited in those articles, and the third database comprises 830 citations retrieved from the NASA Astrophysics Data System, in addition to the archive that contains the complete text of the articles for their thematic analysis. For the interpretation of these data, several indicators and mathematical models were used which give us both the characteristics of the scientific communication of this author over the course of 44 years as well as the characteristics of the citations received.

  8. On-Line Bibliometric Analysis for Researchers and Educators.

    ERIC Educational Resources Information Center

    Baker, Donald R.

    1991-01-01

    A computer-based bibliometric study tracking the growth of dissertation and book production in social work from 1959-88 is reported. Potential applications of online bibliometric analysis are discussed, including its use in evaluation of scholarly productivity, study of social work history, and management of knowledge development processes in…

  9. The Nature of a Discipline--A Bibliometric Study of Communication with Some Comparisons to Library Reference/Information Work.

    ERIC Educational Resources Information Center

    Dick, Joan; Blazek, Ron

    1995-01-01

    A 10-year period of professional literature in the "Communication Yearbook" was subjected to bibliometric analysis. Content of the articles was analyzed and compared for frequency of mention of research programs, theories, and methodologies. Similarities in the field of librarianship, notably reference/information work, were identified.…

  10. Trends in scientific activity addressing transmissible spongiform encephalopathies: a bibliometric study covering the period 1973–2002

    PubMed Central

    Sanz-Casado, Elías; Ramírez-de Santa Pau, Margarita; Suárez-Balseiro, Carlos A; Iribarren-Maestro, Isabel; de Pedro-Cuesta, Jesús

    2006-01-01

    Background The purpose of this study is to analyse the trends in scientific research on transmissible spongiform encephalopathies by applying bibliometric tools to the scientific literature published between 1973 and 2002. Methods The data for the study were obtained from Medline database, in order to determine the volume of scientific output in the above period, the countries involved, the type of document and the trends in the subject matters addressed. The period 1973–2002 was divided in three sub-periods. Results We observed a significant growth in scientific production. The percentage of increase is 871.7 from 1973 to 2002. This is more evident since 1991 and particularly in the 1996–2001 period. The countries found to have the highest output were the United States, the United Kingdom, Japan, France and Germany. The evolution in the subject matters was almost constant in the three sub-periods in which the study was divided. In the first and second sub-periods, the subject matters of greatest interest were more general, i.e Nervous system or Nervous system diseases, Creutzfeldt-Jakob disease, Scrapie, and Chemicals and Drugs, but in the last sub-period, some changes were observed because the Prion-related matters had the greatest presence. Collaboration among authors is small from 1973 to 1992, but increases notably in the third sub-period, and also the number of authors and clusters formed. Some of the authors, like Gajdusek or Prusiner, appear in the whole period. Conclusion The study reveals a very high increase in scientific production. It is related also with the beginnings of research on bovine spongiform encephalopathy and variant Creutzfeldt-Jakob disease, with the establishment of progressive collaboration relationships and a reflection of public health concerns about this problem. PMID:17026743

  11. Scholarly Communication and Bibliometrics.

    ERIC Educational Resources Information Center

    Borgman, Christine L.; Furner, Jonathan

    2002-01-01

    This review of scholarly communication and bibliometrics discusses relational link analysis; evaluative link analysis; measures of evaluation for documents, people, journals, organizations, and nations; theoretical foundations of link analysis; author self-citation; quality; popularity; citation-worthiness; credit-worthiness; digital libraries;…

  12. Bibliometric Evaluation of the Changing Finnish Astronomy

    NASA Astrophysics Data System (ADS)

    Isaksson, E.

    2010-10-01

    This is a follow-up on the bibliometric evaluation of Finnish astronomy presented by the author at the LISA V conference in 2006. The data from the previous study are revisited to determine how a wider institutional base and mergers affect comparisons between research units.

  13. Climate Change Research in View of Bibliometrics

    PubMed Central

    Haunschild, Robin; Bornmann, Lutz; Marx, Werner

    2016-01-01

    This bibliometric study of a large publication set dealing with research on climate change aims at mapping the relevant literature from a bibliometric perspective and presents a multitude of quantitative data: (1) The growth of the overall publication output as well as (2) of some major subfields, (3) the contributing journals and countries as well as their citation impact, and (4) a title word analysis aiming to illustrate the time evolution and relative importance of specific research topics. The study is based on 222,060 papers (articles and reviews only) published between 1980 and 2014. The total number of papers shows a strong increase with a doubling every 5–6 years. Continental biomass related research is the major subfield, closely followed by climate modeling. Research dealing with adaptation, mitigation, risks, and vulnerability of global warming is comparatively small, but their share of papers increased exponentially since 2005. Research on vulnerability and on adaptation published the largest proportion of very important papers (in terms of citation impact). Climate change research has become an issue also for disciplines beyond the natural sciences. The categories Engineering and Social Sciences show the strongest field-specific relative increase. The Journal of Geophysical Research, the Journal of Climate, the Geophysical Research Letters, and Climatic Change appear at the top positions in terms of the total number of papers published. Research on climate change is quantitatively dominated by the USA, followed by the UK, Germany, and Canada. The citation-based indicators exhibit consistently that the UK has produced the largest proportion of high impact papers compared to the other countries (having published more than 10,000 papers). Also, Switzerland, Denmark and also The Netherlands (with a publication output between around 3,000 and 6,000 papers) perform top—the impact of their contributions is on a high level. The title word analysis shows

  14. Climate Change Research in View of Bibliometrics.

    PubMed

    Haunschild, Robin; Bornmann, Lutz; Marx, Werner

    2016-01-01

    This bibliometric study of a large publication set dealing with research on climate change aims at mapping the relevant literature from a bibliometric perspective and presents a multitude of quantitative data: (1) The growth of the overall publication output as well as (2) of some major subfields, (3) the contributing journals and countries as well as their citation impact, and (4) a title word analysis aiming to illustrate the time evolution and relative importance of specific research topics. The study is based on 222,060 papers (articles and reviews only) published between 1980 and 2014. The total number of papers shows a strong increase with a doubling every 5-6 years. Continental biomass related research is the major subfield, closely followed by climate modeling. Research dealing with adaptation, mitigation, risks, and vulnerability of global warming is comparatively small, but their share of papers increased exponentially since 2005. Research on vulnerability and on adaptation published the largest proportion of very important papers (in terms of citation impact). Climate change research has become an issue also for disciplines beyond the natural sciences. The categories Engineering and Social Sciences show the strongest field-specific relative increase. The Journal of Geophysical Research, the Journal of Climate, the Geophysical Research Letters, and Climatic Change appear at the top positions in terms of the total number of papers published. Research on climate change is quantitatively dominated by the USA, followed by the UK, Germany, and Canada. The citation-based indicators exhibit consistently that the UK has produced the largest proportion of high impact papers compared to the other countries (having published more than 10,000 papers). Also, Switzerland, Denmark and also The Netherlands (with a publication output between around 3,000 and 6,000 papers) perform top-the impact of their contributions is on a high level. The title word analysis shows that

  15. Plethora or paucity: a systematic search and bibliometric study of the application and design of qualitative methods in nursing research 2008-2010.

    PubMed

    Ball, Elaine; McLoughlin, Moira; Darvill, Angela

    2011-04-01

    Qualitative methodology has increased in application and acceptability in all research disciplines. In nursing, it is appropriate that a plethora of qualitative methods can be found as nurses pose real-world questions to clinical, cultural and ethical issues of patient care (Johnson, 2007; Long and Johnson, 2007), yet the methods nurses readily use in pursuit of answers remains under intense scrutiny. One of the problems with qualitative methodology for nursing research is its place in the hierarchy of evidence (HOE); another is its comparison to the positivist constructs of what constitutes good research and the measurement of qualitative research against this. In order to position and strengthen its evidence base, nursing may well seek to distance itself from a qualitative perspective and utilise methods at the top of the HOE; yet given the relation of qualitative methods to nursing this would constrain rather than broaden the profession in search of answers and an evidence base. The comparison between qualitative and quantitative can be both mutually exclusive and rhetorical, by shifting the comparison this study takes a more reflexive position and critically appraises qualitative methods against the standards set by qualitative researchers. By comparing the design and application of qualitative methods in nursing over a two year period, the study examined how qualitative stands up to independent rather than comparative scrutiny. For the methods, a four-step mixed methods approach newly constructed by the first author was used to define the scope of the research question and develop inclusion criteria. 2. Synthesis tables were constructed to organise data, 3. Bibliometrics configured data. 4. Studies selected for inclusion in the review were critically appraised using a critical interpretive synthesis (Dixon-Woods et al., 2006). The paper outlines the research process as well as findings. Results showed of the 240 papers analysed, 27% used ad hoc or no

  16. Bibliometrics: From Curiosity to Convention.

    ERIC Educational Resources Information Center

    White, Emilie C.

    1985-01-01

    Reports on applications of bibliometrics (measurement of book or compositional entities according to methods that yield comparable results) in the field of information science. Highlights include quantification and qualification, Bradford's Law of Scattering, applications and classifications of citation analysis, and bibliometrics in library…

  17. Bibliometric study of articles published in a Brazilian journal of pediatric dentistry.

    PubMed

    Poletto, Vanessa Ceolin; Faraco Junior, Italo Medeiros

    2010-01-01

    This cross-sectional study aimed at evaluating the abstracts of all articles published in the 'Jornal Brasileiro de Odontopediatria e Odontologia do Bebê' in order to collect data on the study design used, the most researched topics and the Brazilian states with the highest scientific production. Copies were made of the abstracts of each article, totaling 572 abstracts. Data categorization was done by two trained and independent reviewers. The results showed that the most used study design were case report (33%) and cross-sectional study (30%). On the other hand, there were only 2.5% of randomized clinical trials and no systematic review or meta-analysis. The most researched topics were cariology (15%) and restorative dentistry / dental materials (10%). The state with the greatest number of publications was São Paulo (40%), followed by Rio de Janeiro (17%). It was concluded that the majority of the articles published referred to studies with a low potential to establish scientific evidence, indicating a need for conducting research based on better quality methodology. Moreover, it was found that the assessed literature reflected the trends observed in the clinical practice of Pediatric Dentistry in Brazil. PMID:20339719

  18. A Bibliometric Study of Scholarly Articles Published by Library and Information Science Authors about Open Access

    ERIC Educational Resources Information Center

    Grandbois, Jennifer; Beheshti, Jamshid

    2014-01-01

    Introduction: This study aims to gain a greater understanding of the development of open access practices amongst library and information science authors, since their role is integral to the success of the broader open access movement. Method: Data were collected from scholarly articles about open access by library and information science authors…

  19. Three Decades of "Suicide and Life-Threatening Behavior": A Bibliometric Study

    ERIC Educational Resources Information Center

    Cardinal, Charles

    2008-01-01

    The purpose of this study is to quantify certain characteristics of the articles published in "Suicide and Life-Threatening Behavior" in three 5-year periods, namely, 1971-1975, 1984-1988, and 1997-2001. The characteristics in question include geographic origin of articles, number of authors per article, number of references listed per article,…

  20. A bibliometric study of publication patterns in access to medicines research in developing countries

    PubMed Central

    Ritz, Lindsay Sarah; Adam, Taghreed; Laing, Richard

    2010-01-01

    Objectives: Developing countries face considerable problems in both accessing and properly utilizing essential medicines. One challenge to achieving these goals in resource-poor settings is a limited knowledge base as to what works to improve the selection, access and use of essential medicines including; ways to ensure affordable prices, increase sustainable financing, and strengthen reliable supply systems that are relevant to these settings. The objective of this study was to search the existing evidence base on access to medicine issues in developing countries and to assess publication patterns regarding the nature of topics studied, areas where gaps of information exist and the general trends in publications in this area. Methods: A PubMed search was conducted to retrieve publications on access to medicines in developing countries between 1999-2008. Our search strategy builds and expands on a search strategy developed for a Cochrane review to include a wider range of topics related to access to medicines and pharmaceutical policy. Retrieved articles were categorized by research topics, year of publication, study area, and country of residence of corresponding author to establish patterns in publications with respect to these categories over the past 10 years. Results: Medicine selection, intellectual property rights, and monitoring and quality assurance were among the top topics studied over the last 10 years. Corresponding authors residing in high-income countries represented around 50% of all publications relative to low-income (18%) and middle-income countries (32%). Although an increasing trend in the number of publications per year was found, the increase was relatively small and variable over a 10-year period. Conclusions: There are few peer-reviewed publications on access to medicines in developing countries with an average of only 76 publications per year over the past 10 years. Increasing the local evidence base as to what works to improve access to

  1. Finite Element Analysis Generates an Increasing Interest in Dental Research: A Bibliometric Study

    PubMed Central

    Diarra, Abdoulaziz; Mushegyan, Vagan; Naveau, Adrien

    2016-01-01

    Purpose: The purpose was to provide a longitudinal overview of published studies that use finite element analysis in dental research, by using the SCI-expanded database of Web of Science® (Thomson Reuters). Material and Methods: Eighty publications from 1999-2000 and 473 from 2009-2010 were retrieved. This literature grew faster than the overall dental literature. The number of publishing countries doubled. The main journals were American or English, and dealt with implantology. For the top 10 journals publishing dental finite element papers, the mean impact factor increased by 75% during the decade. Results: Finite elements generate an increasing interest from dental authors and publishers worldwide. PMID:27006722

  2. European Non-Communicable Respiratory Disease Research, 2002-13: Bibliometric Study of Outputs and Funding

    PubMed Central

    Wright, John S. F.; Pallari, Elena; Sullivan, Richard

    2016-01-01

    This study was conducted in order to map European research in chronic respiratory diseases (CRDs). It was intended to assist the European Commission and other research funders to identify gaps and overlaps in their portfolios, and to suggest ways in which they could improve the effectiveness of their support and increase the impact of the research on patient care and on the reduction of the incidence of the CRDs. Articles and reviews were identified in the Web of Science on research in six non-communicable respiratory diseases that were published in 2002–13 from 31 European countries. They represented only 0.8% of biomedical research output but these diseases accounted for 4.7% of the European disease burden, as measured by Disability-Adjusted Life Years (DALYs), so the sub-field is seriously under-researched. Europe is prominent in the sub-field and published 56% of the world total, with the UK the most productive and publishing more than France and Italy, the next two countries, combined. Asthma and Chronic Obstructive Pulmonary Disease (COPD) were the diseases with the most publications and the highest citation rates. They also received the most funding, with around two acknowledgments per paper (in 2009–13), whereas cystic fibrosis and emphysema averaged only one. Just over 37% of papers had no specific funding and depended on institutional support from universities and hospitals. PMID:27111670

  3. European Non-Communicable Respiratory Disease Research, 2002-13: Bibliometric Study of Outputs and Funding.

    PubMed

    Begum, Mursheda; Lewison, Grant; Wright, John S F; Pallari, Elena; Sullivan, Richard

    2016-01-01

    This study was conducted in order to map European research in chronic respiratory diseases (CRDs). It was intended to assist the European Commission and other research funders to identify gaps and overlaps in their portfolios, and to suggest ways in which they could improve the effectiveness of their support and increase the impact of the research on patient care and on the reduction of the incidence of the CRDs. Articles and reviews were identified in the Web of Science on research in six non-communicable respiratory diseases that were published in 2002-13 from 31 European countries. They represented only 0.8% of biomedical research output but these diseases accounted for 4.7% of the European disease burden, as measured by Disability-Adjusted Life Years (DALYs), so the sub-field is seriously under-researched. Europe is prominent in the sub-field and published 56% of the world total, with the UK the most productive and publishing more than France and Italy, the next two countries, combined. Asthma and Chronic Obstructive Pulmonary Disease (COPD) were the diseases with the most publications and the highest citation rates. They also received the most funding, with around two acknowledgments per paper (in 2009-13), whereas cystic fibrosis and emphysema averaged only one. Just over 37% of papers had no specific funding and depended on institutional support from universities and hospitals. PMID:27111670

  4. Dental research in Spain. A bibliometric analysis on subjects, authors and institutions (1993-2012)

    PubMed Central

    Bueno-Aguilera, Felipe; Lucena-Martín, Cristina; Pulgar-Encinas, Rosa

    2016-01-01

    Background Bibliometrics is defined as the use of statistical methods in the analysis of a body of literature to reveal the historical development of subject fields and patterns of authorship, publication, and use. Our objective was to characterize Spanish scientific output in Dentistry through the analysis of Web of Science database in a 20-year period. By means of a bibliometric study documents were statistically analyzed using indicators that showed quantitative and qualitative aspects of the production. Specifically, time course of the scientific production within the time span was analysed, as were the journals where the article was published and the categories of Journal Citation Reports (JCR) in which they belong, thematic areas, authorship, and finally authors and institutions with the highest production in Spain. Material and Methods By means of the design of a specific search strategy previously described in the scientific literature, we recovered all citable documents about Dentistry signed by Spanish researchers and included in the WoS database between 1993 and 2012. Results A total of 3006 documents fulfilled the search criteria, of which 2449 (81.5%) were published in journals within the category Dentistry Oral Surgery and Medicine and 557 (18.5%) within other categories of the JCR. During the four quinquenniums studied, the production increased quantitatively (8.6-fold) and qualitatively. Finally, the universities of Granada and Complutense of Madrid were the institutions with the highest production and most prolific authors. Conclusions The Spanish dental production sharply increased in the last two decades, reaching quantitative and qualitative levels similar to those of the other medical specialties in the country. Key words:Dental research, dentistry, publications, Journal impact factor, bibliometrics, biomedical research, Spanish dental production. PMID:26827056

  5. Quantitative studies in radiopharmaceutical science

    SciTech Connect

    Cooper, M.; Beck, R.N.

    1989-09-01

    The scientific direction of the work in this grant is unchanged and the 12 research projects in the three major categories represent only minor modification from the proposed work given at site visit. Adjustment was necessary in keeping with the award and to accommodate the resignation of Dr. S. John Gatley who took a position at the Brookhaven National Laboratories. Significant progress is being made in each scientific area with principal responsibility in radiochemistry now assumed by J. Mukherjee and S. Murphy, both of whom have contributed major advances in their areas of fluorination of receptor ligands for studies of the dopaminergic system and approaches to studies of the glutamate type II receptors, respectively. C.T. Chen's work in quantitative method approaches to image integration and analysis continues to receive national and international attention. Similar attention is being given to J. Metz and H. deWit with their work on the effects of drugs of dependency on mood and regional brain metabolism. Resource development in the overall program has been substantial. An equipment grant totaling $350,000 was awarded to the Frank Center for Image Analysis of the FMI by the W.M. Keck Foundation through The University of Chicago/Argonne National Laboratory Center for Imaging Science for purchasing computer systems for graphic display, visualization of 2D and 3D image data, and fast computation. We have purchased nine VAXstations, five DECstations, two SUN/SPARCstations, one AT T Pixel Machine system, and the associated communication links for networking. These systems are currently being installed and tested. This facility will provide added computation capabilities for and facilitate the development of the research projects. 39 refs., 4 figs.

  6. Automated Research Impact Assessment: A New Bibliometrics Approach

    PubMed Central

    Drew, Christina H.; Pettibone, Kristianna G.; Finch, Fallis Owen; Giles, Douglas; Jordan, Paul

    2016-01-01

    As federal programs are held more accountable for their research investments, The National Institute of Environmental Health Sciences (NIEHS) has developed a new method to quantify the impact of our funded research on the scientific and broader communities. In this article we review traditional bibliometric analyses, address challenges associated with them, and describe a new bibliometric analysis method, the Automated Research Impact Assessment (ARIA). ARIA taps into a resource that has only rarely been used for bibliometric analyses: references cited in “important” research artifacts, such as policies, regulations, clinical guidelines, and expert panel reports. The approach includes new statistics that science managers can use to benchmark contributions to research by funding source. This new method provides the ability to conduct automated impact analyses of federal research that can be incorporated in program evaluations. We apply this method to several case studies to examine the impact of NIEHS funded research. PMID:26989272

  7. Scale-Independent Bibliometric Indicators

    ERIC Educational Resources Information Center

    Katz, J. Sylvan

    2005-01-01

    This article presents the author's critique of Anthony F. J. van Raan's article titled, "Measurement of Central Aspects of Scientific Research: Performance, Interdisciplinarity, Structure." van Raan makes an excellent case for using bibliometric data to measure some central aspects of scientific research and to construct indicators of groups:…

  8. The Methods of Library Science Research: Some Results from a Bibliometric Survey.

    ERIC Educational Resources Information Center

    Peritz, Bluma C.

    1980-01-01

    The findings of a bibliometric survey of research papers published in 39 core journals of librarianship provide information on study methodologies, growth of the research literature, organizations studied, computer-based operations, users, and major themes of library research. (CHC)

  9. Next Generation Bibliometrics and the Evolution of the ESO Telescope Bibliography

    NASA Astrophysics Data System (ADS)

    Erdmann, C.; Grothkopf, U.

    2010-10-01

    Bibliometric studies typically focus on citation and publication analysis. Due to recent advances in web technology along with greater access to web content, bibliometric research can include statistics and measures that were once difficult to obtain. The European Southern Observatory's Telescope Bibliography (ESO telbib), a content management system for refereed articles containing ESO data, provides an excellent test-bed for exploring next generation bibliometrics. Through web services provided by the NASA Astrophysics Data System (ADS) Abstract Service among others, previously unavailable information can be imported into telbib where it can be analyzed in further detail. Though some telbib features are still in their infancy, some interesting trends can already be derived.

  10. Cell Phones: A Bibliometric Analysis Related to Business Students

    ERIC Educational Resources Information Center

    Piotrowski, Chris

    2014-01-01

    Recent reviews of the literature indicate that the scope of research on cell or mobile phones covers a vast typology (Piotrowski & Kass, 2013). The majority of this research is concentrated in the technology, education, and social sciences fields. However, there is a dearth of bibliometric studies on cell phones related to business. To that…

  11. CALL: Past, Present and Future--A Bibliometric Approach

    ERIC Educational Resources Information Center

    Jung, Udo O. H.

    2005-01-01

    A bibliometric approach is used not only to sketch out the development of CALL during the last 25 years, but also to assess the contribution of educational technology to 21st century foreign-language teaching and learning. This study is based on the six instalments of the author's International (and multilingual) Bibliography of Computer Assisted…

  12. Analysis of bibliometric indicators to determine citation bias

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Publications from the 1995 to 2004 period (and cited throughout July 2013) were analyzed to determine if the plant species used in research studies influenced the number of citations that papers received. Bibliometric data of papers from 108 plant species were obtained for the research fields of Gen...

  13. Reviewers’ Ratings and Bibliometric Indicators: Hand in Hand When Assessing Over Research Proposals?

    PubMed Central

    Cabezas-Clavijo, Álvaro; Robinson-García, Nicolás; Escabias, Manuel; Jiménez-Contreras, Evaristo

    2013-01-01

    Background The peer review system has been traditionally challenged due to its many limitations especially for allocating funding. Bibliometric indicators may well present themselves as a complement. Objective We analyze the relationship between peers’ ratings and bibliometric indicators for Spanish researchers in the 2007 National R&D Plan for 23 research fields. Methods and Materials We analyze peers’ ratings for 2333 applications. We also gathered principal investigators’ research output and impact and studied the differences between accepted and rejected applications. We used the Web of Science database and focused on the 2002-2006 period. First, we analyzed the distribution of granted and rejected proposals considering a given set of bibliometric indicators to test if there are significant differences. Then, we applied a multiple logistic regression analysis to determine if bibliometric indicators can explain by themselves the concession of grant proposals. Results 63.4% of the applications were funded. Bibliometric indicators for accepted proposals showed a better previous performance than for those rejected; however the correlation between peer review and bibliometric indicators is very heterogeneous among most areas. The logistic regression analysis showed that the main bibliometric indicators that explain the granting of research proposals in most cases are the output (number of published articles) and the number of papers published in journals that belong to the first quartile ranking of the Journal Citations Report. Discussion Bibliometric indicators predict the concession of grant proposals at least as well as peer ratings. Social Sciences and Education are the only areas where no relation was found, although this may be due to the limitations of the Web of Science’s coverage. These findings encourage the use of bibliometric indicators as a complement to peer review in most of the analyzed areas. PMID:23840840

  14. Bibliometric indexes, databases and impact factors in cardiology.

    PubMed

    Bienert, Igor R C; Oliveira, Rogério Carvalho de; Andrade, Pedro Beraldo de; Caramori, Carlos Antonio

    2015-01-01

    Bibliometry is a quantitative statistical technique to measure levels of production and dissemination of knowledge, as well as a useful tool to track the development of an scientific area. The valuation of production required for recognition of researchers and magazines is accomplished through tools called bibliometric indexes, divided into quality indicators and scientific impact. Initially developed for monographs of statistical measures especially in libraries, today bibliometrics is mainly used to evaluate productivity of authors and citation repercussion. However, these tools have limitations and sometimes provoke controversies about indiscriminate application, leading to the development of newer indexes. It is important to know the most common search indexes and use it properly even acknowledging its limitations as it has a direct impact in their daily practice, reputation and funds achievement. PMID:26107458

  15. Global Regulatory T-Cell Research from 2000 to 2015: A Bibliometric Analysis.

    PubMed

    Zongyi, Yin; Dongying, Chen; Baifeng, Li

    2016-01-01

    We aimed to analyze the global scientific output of regulatory T-cell (Treg) research and built a model to qualitatively and quantitatively evaluate publications from 2000 to 2015. Data were obtained from the Web of Science Core Collection (WoSCC) of Thomson Reuters on January 1, 2016. The bibliometric method and Citespace III were used to analyze authors, journals, publication outputs, institutions, countries, research areas, research hotspots, and trends. In total, we identified 35,741 publications on Treg research from 2000 to 2015, and observed that the annual publication rate increased with time. The Journal of Immunology published the highest number of articles, the leading country was the USA, and the leading institute was Harvard University. Sakaguchi, Hori, Fontenot, and Wang were the top authors in Treg research. Immunology accounted for the highest number of publications, followed by oncology, experimental medicine, cell biology, and hematology. Keyword analysis indicated that autoimmunity, inflammation, cytokine, gene expression, foxp3, and immunotherapy were the research hotspots, whereas autoimmune inflammation, gene therapy, granzyme B, RORγt, and th17 were the frontiers of Treg research. This bibliometric analysis revealed that Treg-related studies are still research hotspots, and that Treg-related clinical therapies are the research frontiers; however, further study and collaborations are needed worldwide. Overall, our findings provide valuable information for the editors of immunology journals to identify new perspectives and shape future research directions. PMID:27611317

  16. Nursing informatics competencies: bibliometric analysis.

    PubMed

    Kokol, Peter; Blažun, Helena; Vošner, Janez; Saranto, Kaija

    2014-01-01

    Information and communication technology is developing rapidly and it is incorporated in many health care processes, but in spite of that fact we can still notice that nursing informatics competencies had received limited attention in basic nursing education curricula in Europe and especially in Eastern European countries. The purpose of the present paper is to present the results of a bibliometric analysis of the nursing informatics competencies scientific literature production. We applied the bibliometrics analysis to the corpus of 332 papers found in SCOPUS, related to nursing informatics competencies. The results showed that there is a positive trend in the number of published papers per year, indicating the increased research interest in nursing informatics competencies. Despite the fact that the first paper was published in Denmark, the most prolific country regarding the research in nursing informatics competencies is United States as are their institutions and authors. PMID:24943565

  17. Bibliometric Evaluation of Finnish Astronomy

    NASA Astrophysics Data System (ADS)

    Isaksson, E.

    2007-10-01

    Finnish astronomy publishing provides us with an interesting data sample. It is small but not too small: approximately one thousand articles have been published in a decade. There are only four astronomy institutes to be compared. An interesting paradox also emerges in the field: while Finnish science assessments usually value highly the impact of scientific publishing, no serious evaluations using real bibliometric data have been made. To remedy this, a comprehensive ten-year database of refereed papers was collected and analyzed.

  18. Quantitative genetic studies of antisocial behaviour.

    PubMed

    Viding, Essi; Larsson, Henrik; Jones, Alice P

    2008-08-12

    This paper will broadly review the currently available twin and adoption data on antisocial behaviour (AB). It is argued that quantitative genetic research can make a significant contribution to further the understanding of how AB develops. Genetically informative study designs are particularly useful for investigating several important questions such as whether: the heritability estimates vary as a function of assessment method or gender; the relative importance of genetic and environmental influences varies for different types of AB; the environmental risk factors are truly environmental; and genetic vulnerability influences susceptibility to environmental risk. While the current data are not yet directly translatable for prevention and treatment programmes, quantitative genetic research has concrete translational potential. Quantitative genetic research can supplement neuroscience research in informing about different subtypes of AB, such as AB coupled with callous-unemotional traits. Quantitative genetic research is also important in advancing the understanding of the mechanisms by which environmental risk operates. PMID:18434281

  19. Ascertaining Activities in a Subject Area Through Bibliometric Analysis; Application to "Library Literature"

    ERIC Educational Resources Information Center

    Saracevic, Tefko; Perk, Lawrence J.

    1973-01-01

    A combination of quantitative and qualitative techniques were used to analize the journal articles indexed in one volume of Library Literature.'' This approach, merging bibliometrics and classification, yielded results in such areas as dispersion of articles among journals, frequency of article type and types of subjects covered. (16 references)…

  20. Rain research with disdrometers: a bibliometric review

    NASA Astrophysics Data System (ADS)

    Fernandez-Raga, M.; Palencia, C.; Tomas, C.; Calvo, A. I.; Castro, A.; Fraile, R.

    2011-09-01

    This study analyses the research on disdrometers based on published studies. To do so, a wide data base of bibliographic references has been used: the Web of Science (published by Thomson Reuters). The search was carried out for all of the articles whose "TOPIC" was disdrometer. The more than 300 articles found were analysed according to various criteria: countries with research using disdrometers; publication dates; evolution of the number of articles; concepts studied and research lines followed in each article; and finally, a bibliometric analysis of the more than 60 journals where these articles have been published. Since 1963, there has been an increase in the number of articles published on disdrometers, which in the last 20 yr has been more than ten times higher than the increase in the number of articles on meteorology.

  1. Critical Quantitative Study of Immigrant Students

    ERIC Educational Resources Information Center

    Conway, Katherine M.

    2014-01-01

    The author discusses the importance of critical quantitative research for studies of immigrant students, a large and growing group, whose higher education experience is crucial to the future of the United States. The author outlines some of the distinctions to be made among immigrant students and recommends areas of future inquiry.

  2. Characteristics and popular topics of latest researches into the effects of air particulate matter on cardiovascular system by bibliometric analysis.

    PubMed

    Jia, Xiaofeng; Guo, Xinbiao; Li, Haicun; An, Xinying; Zhao, Yingguang

    2013-03-01

    In recent years, many epidemiological and toxicological studies have investigated the adverse effects of air particulate matter (PM) on the cardiovascular system. However, it is difficult for the researchers to have a timely and effective overall command of the latest characteristics and popular topics in such a wide field. Different from the previous reviews, in which the research characteristics and trends are empirically concluded by experts, we try to have a comprehensive evaluation of the above topics for the first time by bibliometric analysis, a quantitative tool in information exploration. This study aims to introduce the bibliometric method into the field of PM and cardiovascular system. The articles were selected by searching PubMed/MEDLINE (from 2007 to 2012) using Medical Subject Headings (MeSH) terms "particulate matter" and "cardiovascular system". A total of 935 eligible articles and 1895 MeSH terms were retrieved and processed by the software Thomson Data Analyzer (TDA). The bibliographic information and the MeSH terms of these articles were classified and analyzed to summarize the research characteristics. The top 200 high-frequency MeSH terms (the cumulative frequency percentage was 74.2%) were clustered for popular-topic conclusion. We summarized the characteristics of published articles, of researcher collaborations and of the contents. Ten clusters of MeSH terms are presented. Six popular topics are concluded and elaborated for reference. Our study presents an overview of the characteristics and popular topics in the field of PM and cardiovascular system in the past five years by bibliometric tools, which may provide a new perspective for future researchers. PMID:23480197

  3. Examining the Literature: A Bibliometric Study of ESD Journal Articles in the Education Resources Information Center Database

    ERIC Educational Resources Information Center

    Wright, Tarah; Pullen, Sarah

    2007-01-01

    Using the tool of bibliometry, this study examines journal articles related to Education for Sustainable Development (ESD) in academic journals from 1990 to 2005. It offers a statistical description of the literature, and analyses the development of ESD publications within the journal literature to date. The results show that the number of ESD…

  4. Spanish personal name variations in national and international biomedical databases: implications for information retrieval and bibliometric studies

    PubMed Central

    Ruiz-Pérez, R.; López-Cózar, E. Delgado; Jiménez-Contreras, E.

    2002-01-01

    Objectives: The study sought to investigate how Spanish names are handled by national and international databases and to identify mistakes that can undermine the usefulness of these databases for locating and retrieving works by Spanish authors. Methods: The authors sampled 172 articles published by authors from the University of Granada Medical School between 1987 and 1996 and analyzed the variations in how each of their names was indexed in Science Citation Index (SCI), MEDLINE, and Índice Médico Español (IME). The number and types of variants that appeared for each author's name were recorded and compared across databases to identify inconsistencies in indexing practices. We analyzed the relationship between variability (number of variants of an author's name) and productivity (number of items the name was associated with as an author), the consequences for retrieval of information, and the most frequent indexing structures used for Spanish names. Results: The proportion of authors who appeared under more then one name was 48.1% in SCI, 50.7% in MEDLINE, and 69.0% in IME. Productivity correlated directly with variability: more than 50% of the authors listed on five to ten items appeared under more than one name in any given database, and close to 100% of the authors listed on more than ten items appeared under two or more variants. Productivity correlated inversely with retrievability: as the number of variants for a name increased, the number of items retrieved under each variant decreased. For the most highly productive authors, the number of items retrieved under each variant tended toward one. The most frequent indexing methods varied between databases. In MEDLINE and IME, names were indexed correctly as “first surname second surname, first name initial middle name initial” (if present) in 41.7% and 49.5% of the records, respectively. However, in SCI, the most frequent method was “first surname, first name initial second name initial” (48.0% of

  5. The bibliometrics of atmospheric environment

    NASA Astrophysics Data System (ADS)

    Brimblecombe, Peter; Grossi, Carlota M.

    Bibliometric analysis is an important tool in the management of a journal. SCOPUS output is used to assess the increase in the quantity of material in Atmospheric Environment and stylistic changes in the way authors choose words and punctuation in titles and assemble their reference lists. Citation analysis is used to consider the impact factor of the journal, but perhaps more importantly the way in which it reflects the importance authors give to papers published in Atmospheric Environment. The impact factor of Atmospheric Environment (2.549 for 2007) from the Journal Citation Reports suggests it performs well within the atmospheric sciences, but it conceals the long term value authors place on papers appearing in the journal. Reference lists show that a fifth come through citing papers more than a decade old.

  6. TECHNOLOGICAL INNOVATION IN NEUROSURGERY: A QUANTITATIVE STUDY

    PubMed Central

    Marcus, Hani J; Hughes-Hallett, Archie; Kwasnicki, Richard M; Darzi, Ara; Yang, Guang-Zhong; Nandi, Dipankar

    2015-01-01

    Object Technological innovation within healthcare may be defined as the introduction of a new technology that initiates a change in clinical practice. Neurosurgery is a particularly technologically intensive surgical discipline, and new technologies have preceded many of the major advances in operative neurosurgical technique. The aim of the present study was to quantitatively evaluate technological innovation in neurosurgery using patents and peer-reviewed publications as metrics of technology development and clinical translation respectively. Methods A patent database was searched between 1960 and 2010 using the search terms “neurosurgeon” OR “neurosurgical” OR “neurosurgery”. The top 50 performing patent codes were then grouped into technology clusters. Patent and publication growth curves were then generated for these technology clusters. A top performing technology cluster was then selected as an exemplar for more detailed analysis of individual patents. Results In all, 11,672 patents and 208,203 publications relating to neurosurgery were identified. The top performing technology clusters over the 50 years were: image guidance devices, clinical neurophysiology devices, neuromodulation devices, operating microscopes and endoscopes. Image guidance and neuromodulation devices demonstrated a highly correlated rapid rise in patents and publications, suggesting they are areas of technology expansion. In-depth analysis of neuromodulation patents revealed that the majority of high performing patents were related to Deep Brain Stimulation (DBS). Conclusions Patent and publication data may be used to quantitatively evaluate technological innovation in neurosurgery. PMID:25699414

  7. Hailpad-based research: A bibliometric review

    NASA Astrophysics Data System (ADS)

    Palencia, Covadonga; Castro, Amaya; Giaiotti, Dario; Stel, Fulvio; Vinet, Freddy; Fraile, Roberto

    This paper is an overview of hailpad research from its origin until today using as a search criterion the bibliographic references on the subject in the Web of Science database (ISI). The search was carried out on 1st September 2008. Among the more than 3·10 7 scientific documents included in the Science Citation Index Expanded (SCI-EXPANDED) from 1945 to the present, the search engine identified 41 containing the word "hailpad*" (the asterisk is a wildcard for any letter or group of letters). The results have been analyzed according to various criteria: countries with hailpad networks or studies on hailpads; date of the first article; evolution of the number of articles per decade; concepts studied and research lines followed in each article; and finally, a bibliometric analysis of the journals where these articles have been published. It was found that 70% of the articles on hailpads were published in 2 journals: Journal of Applied Meteorology and Atmospheric Research. These two journals also concentrate most of the citations. The number of articles on hailpads and the documents that cite them have grown steadily, and it is expected to grow still further in the present decade if we take into account the trends found.

  8. Rating Health Web sites using the principles of Citation Analysis: A Bibliometric Approach

    PubMed Central

    1999-01-01

    The rapid growth in the number of health care related web sites necessitates that medical librarians be able to evaluate the quality of the web sites. By analysing the linked sources medical libraries web pages of nineteen of the top U.S. medical schools, this study used the citation analysis method. What was found with this bibliometric approach was a set of 78 most highly cited WWW sites out of thousands of cited links. The identification of the current, core section of health sciences related web sites with a bibliometric method gives librarians and information scientists another approach for evaluating web sites. PMID:11720913

  9. Utilizing Journal Dissertation Listings for Bibliometric Analysis: French History Dissertations 1976-1990

    ERIC Educational Resources Information Center

    Herubel, Jean-Pierre V. M.

    2006-01-01

    The purpose of this study is to demonstrate the use and importance of examining dissertations listed in scholarly journals, while focusing on a critical period of French doctoral education in historical studies. French dissertations in history were bibliometrically examined from "Revue historique," a mainstream history journal published in France.…

  10. Bibliometrics/Theory, Practice and Problems.

    ERIC Educational Resources Information Center

    Narin, Francis; And Others

    1994-01-01

    Theory behind modern evaluative bibliometric techniques is reviewed at three levels: (1) policy application; (2) strategic analysis; and (3) tactical analysis. New techniques developed at each level and limitations of each approach are discussed. At all levels, the process begins with assembling data and then moves to a data-based evaluation. (SLD)

  11. Bibliometrics: Help or Hoax for Quality?

    ERIC Educational Resources Information Center

    Galetto, F.

    2014-01-01

    Higher Education Institutions should provide students good teaching with good professors who have good knowledge of the matter they are teaching. Unfortunately, many times, the opposite happens: career leaps depend on "bibliometric indexes" (Impact Points, "h"-index, "s"-index, "RG"-index,…

  12. Bibliometric indexes, databases and impact factors in cardiology

    PubMed Central

    Bienert, Igor R C; de Oliveira, Rogério Carvalho; de Andrade, Pedro Beraldo; Caramori, Carlos Antonio

    2015-01-01

    Bibliometry is a quantitative statistical technique to measure levels of production and dissemination of knowledge, as well as a useful tool to track the development of an scientific area. The valuation of production required for recognition of researchers and magazines is accomplished through tools called bibliometricindexes, divided into quality indicators and scientific impact. Initially developed for monographs of statistical measures especially in libraries, today bibliometrics is mainly used to evaluate productivity of authors and citation repercussion. However, these tools have limitations and sometimes provoke controversies about indiscriminate application, leading to the development of newer indexes. It is important to know the most common search indexes and use it properly even acknowledging its limitations as it has a direct impact in their daily practice, reputation and funds achievement. PMID:26107458

  13. [Quantitative pharmaco-EEG study of nootropics].

    PubMed

    Kinoshita, T

    1990-01-01

    A treatment of geriatric disorders is one of the current major problems socially as well as medically. Thus nootropics have become one of the biggest topics in drug developments. Unfortunately, it is still very difficult to assess brain dysfunctions and therapeutic efficacies of these drugs objectively. Giurgea has proposed a new drug category, "nootropic", as those substances which possess an anti-dementia action, yet the general concept remains obscure. The present author expand the concept that those substances which improve the vigilance level to be included. The author has been engaged with computer assisted pharmaco-electroencephalography and research of nootropics for last several years. Based on the own experiences, the author presented the CNS effects of five different substances such as meclofenoxate, amantadine, piracetam, teniloxazine and WEB-1881, which were regarded as nootropics from various reasons. Single dose of each substances was administered in healthy young volunteers, and teniloxazine was given to geriatric patients. EEG changes induced by these substances in normal subjects were an increase of alpha activity, particularly in higher frequency range above 9.5 Hz, and an associated decrease of slow activity and of fast activity, which are different from those of the other psychotropic drugs. Multivariate analysis of variance (MANOVA) of EEG parameters has confirmed that the response of WEB-1881 was most manifest in frontal area. This suggests that WEB-1881 might activate linguistic learning and memory process. In the patient study, the induced EEG changes were an increase of alpha activity associated with a decrease of slow activity, while fast activity did not show any changes. However, the EEG changes in the patient study were quite similar to those of normal volunteer study for the most part. It is relevant to infer the efficacy of nootropics in geriatric patients from acute normal volunteer study. In physiological aging process, alpha

  14. Research Productivity and Performance of Journals in the Creativity Sciences: A Bibliometric Analysis

    ERIC Educational Resources Information Center

    Long, Haiying; Plucker, Jonathan A.; Yu, Qi; Ding, Ying; Kaufman, James C.

    2014-01-01

    A bibliometric approach was employed to analyze the research productivity and performance of creativity studies between 1965 and 2012. A dataset was constructed using all publications and citations retrieved from four key journals that publish creativity research: "Journal of Creative Behavior" ("JCB"), "Gifted Child…

  15. A Bibliometric Snapshot of "The Journal of Higher Education" and Its Impact on the Field

    ERIC Educational Resources Information Center

    Earp, Vanessa J.

    2010-01-01

    In recent decades the field of higher education has grown exponentially; however, little research examines a particular journal and its impact on the field. The purpose of this study was to conduct a brief bibliometric analysis and discuss the impact of "The Journal of Higher Education" (1998-2002), a premier journal in the discipline. (Contains 6…

  16. Relationships between Association of Research Libraries (ARL) Statistics and Bibliometric Indicators: A Principal Components Analysis

    ERIC Educational Resources Information Center

    Hendrix, Dean

    2010-01-01

    This study analyzed 2005-2006 Web of Science bibliometric data from institutions belonging to the Association of Research Libraries (ARL) and corresponding ARL statistics to find any associations between indicators from the two data sets. Principal components analysis on 36 variables from 103 universities revealed obvious associations between…

  17. The Non-Gaussian Nature of Bibliometric and Scientometric Distributions: A New Approach to Interpretation.

    ERIC Educational Resources Information Center

    Ivancheva, Ludmila E.

    2001-01-01

    Discusses the concept of the hyperbolic or skew distribution as a universal statistical law in information science and socioeconomic studies. Topics include Zipf's law; Stankov's universal law; non-Gaussian distributions; and why most bibliometric and scientometric laws reveal characters of non-Gaussian distribution. (Author/LRW)

  18. Attitudes towards Disability in Education through the SSCI (2000-2011): A Topical and Bibliometric Analysis

    ERIC Educational Resources Information Center

    Garcia-Fernandez, Jose Manuel; Ingles, Candido J.; Juan, Maria Vicent; Gonzalvez-Macia, Carolina; Manas-Viejo, Carmen

    2013-01-01

    Introduction: The purpose of this study is to describe and characterize the international scientific output relating to "attitudes towards disability in education", using a battery of bibliometric indicators that make it possible to analyze and monitor international scientific activity. Method: This "ex post facto"…

  19. Growth or Steady State? A Bibliometric Focus on International Comparative Higher Education Research

    ERIC Educational Resources Information Center

    Kosmützky, Anna; Krücken, Georg

    2014-01-01

    The study combines a bibliometric approach with a content analysis of abstracts of articles to explore the patterns of international comparative higher education research in leading international journals. The overall data set covers 4,095 publications from the Web of Science for the period 1992-2012 and the amount of international comparative…

  20. Citation Mining: Integrating Text Mining and Bibliometrics for Research User Profiling.

    ERIC Educational Resources Information Center

    Kostoff, Ronald N.; del Rio, J. Antonio; Humenik, James A.; Garcia, Esther Ofilia; Ramirez, Ana Maria

    2001-01-01

    Discusses the importance of identifying the users and impact of research, and describes an approach for identifying the pathways through which research can impact other research, technology development, and applications. Describes a study that used citation mining, an integration of citation bibliometrics and text mining, on articles from the…

  1. A Methodological Approach to Developing Bibliometric Models of Types of Humanities Scholarship.

    ERIC Educational Resources Information Center

    Wiberley, Stephen E., Jr.

    2003-01-01

    Outlines a methodological approach to developing bibliometric models of the sources used in different types of humanities scholarship. Identifies five types of scholarship: description of primary sources, editing of primary sources, historical studies, criticism, and theory. Illustrates the approach through an analysis of sources used in 54…

  2. Subjective Quantitative Studies of Human Agency

    ERIC Educational Resources Information Center

    Alkire, Sabina

    2005-01-01

    Amartya Sen's writings have articulated the importance of human agency, and identified the need for information on agency freedom to inform our evaluation of social arrangements. Many approaches to poverty reduction stress the need for empowerment. This paper reviews "subjective quantitative measures of human agency at the individual level." It…

  3. Nanostructured surfaces investigated by quantitative morphological studies.

    PubMed

    Perani, Martina; Carapezzi, Stefania; Mutta, Geeta Rani; Cavalcoli, Daniela

    2016-05-01

    The morphology of different surfaces has been investigated by atomic force microscopy and quantitatively analyzed in this paper. Two different tools have been employed to this scope: the analysis of the height-height correlation function and the determination of the mean grain size, which have been combined to obtain a complete characterization of the surfaces. Different materials have been analyzed: SiO x N y , InGaN/GaN quantum wells and Si nanowires, grown with different techniques. Notwithstanding the presence of grain-like structures on all the samples analyzed, they present very diverse surface design, underlying that this procedure can be of general use. Our results show that the quantitative analysis of nanostructured surfaces allows us to obtain interesting information, such as grain clustering, from the comparison of the lateral correlation length and the grain size. PMID:27004458

  4. Nanostructured surfaces investigated by quantitative morphological studies

    NASA Astrophysics Data System (ADS)

    Perani, Martina; Carapezzi, Stefania; Rani Mutta, Geeta; Cavalcoli, Daniela

    2016-05-01

    The morphology of different surfaces has been investigated by atomic force microscopy and quantitatively analyzed in this paper. Two different tools have been employed to this scope: the analysis of the height-height correlation function and the determination of the mean grain size, which have been combined to obtain a complete characterization of the surfaces. Different materials have been analyzed: SiO x N y , InGaN/GaN quantum wells and Si nanowires, grown with different techniques. Notwithstanding the presence of grain-like structures on all the samples analyzed, they present very diverse surface design, underlying that this procedure can be of general use. Our results show that the quantitative analysis of nanostructured surfaces allows us to obtain interesting information, such as grain clustering, from the comparison of the lateral correlation length and the grain size.

  5. Geodesy, a Bibliometric Approach for 2000-2006

    NASA Astrophysics Data System (ADS)

    Vazquez, G.; Landeros, C. F.

    2007-12-01

    In recent years, bibliometric science has been frequently applied in the development and evaluation of scientific research. This work presents a bibliometric analysis for the research work performed in the field of geodesy "science of the measurement and mapping of the earth surface including its external gravity field". The objective of this work is to present a complete overview of the generated research on this field to assemble and study the most important publications occurred during the past seven years. The analysis was performed including the SCOPUS and WEB OF SCIENCE databases for all the geodetic scientific articles published between 2000 and 2006. The search profile was designed considering a strategy to seek for titles and article descriptors using the terms geodesy and geodetic and some other terms associated with the topics: geodetic surfaces, vertical measurements, reference systems and frames, modern space-geodetic techniques and satellite missions. Some preliminary results had been achieved specifically Bradford law of distribution for journals and education institutes, and Lotka's law for authors that also includes the cooperation between countries in terms of writing together scientific articles. In the particular case of distributions, the model suggested by Egghe (2002) was adopted for determining the cores.

  6. 75 FR 9488 - Basel Comprehensive Quantitative Impact Study

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-03-02

    ... on December 7, 2007 (72 FR 69288). In an effort to refine the Basel II Capital Accord, the Basel... Office of Thrift Supervision Basel Comprehensive Quantitative Impact Study AGENCY: Office of Thrift... collection. Title of Proposal: Basel Comprehensive Quantitative Impact Study. OMB Number: 1550-0NEW....

  7. Quantitative Articles: Developing Studies for Publication in Counseling Journals

    ERIC Educational Resources Information Center

    Trusty, Jerry

    2011-01-01

    This article is presented as a guide for developing quantitative studies and preparing quantitative manuscripts for publication in counseling journals. It is intended as an aid for aspiring authors in conceptualizing studies and formulating valid research designs. Material is presented on choosing variables and measures and on selecting…

  8. Quantitative assessment of scientific quality

    NASA Astrophysics Data System (ADS)

    Heinzl, Harald; Bloching, Philipp

    2012-09-01

    Scientific publications, authors, and journals are commonly evaluated with quantitative bibliometric measures. Frequently-used measures will be reviewed and their strengths and weaknesses will be highlighted. Reflections about conditions for a new, research paper-specific measure will be presented.

  9. A complex systems approach to bibliometrics

    NASA Astrophysics Data System (ADS)

    Stringer, Michael J.

    Enabled by technological change, we are in the midst of a fundamental shift in how scientific information is produced and communicated. Electronic publishing, preprint archives, blogs, and wikis are emerging as possible viable alternatives to the current journal publishing and peer review system. However, these new technologies flood the environment with information, making it increasingly difficult to find the highest quality and most relevant papers. Additionally, accreditation and quality assessment of published material becomes nearly impossible for agencies interested in funding the research and development that is most likely to succeed. Recently, bibliometric tools have emerged as an effective means for the filtering, accreditation, and assessment of scholarly information. In this thesis, we approach bibliometrics from a complex systems perspective. A unique characteristic of the work presented in this thesis is that we perform empirical validation of bibliometric models using the most comprehensive bibliographic database available. Using these methods, we quantify the dynamics of citations to scientific journals, and investigate the relationship between social network position and research performance.

  10. A generalized approach and computer tool for quantitative genetics study

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Quantitative genetics is one of the most important components to provide valuable genetic information for improving production and quality of plants and animals. The research history of quantitative genetics study could be traced back more than one hundred years. Since the Analysis of Variance (ANOV...

  11. Quantitative Literacy Provision in the First Year of Medical Studies

    ERIC Educational Resources Information Center

    Frith, V.

    2011-01-01

    This article presents a description of and motivation for the quantitative literacy (numeracy) intervention in the first year of medical studies at a South African university. This intervention is a response to the articulation gap between the quantitative literacy of many first-year medical students and the demands of their curriculum.…

  12. Research Performance Evaluation: Some Critical Thoughts on Standard Bibliometric Indicators

    ERIC Educational Resources Information Center

    Anninos, Loukas N.

    2014-01-01

    The bibliometric methodology is an established technique for research evaluation as it offers an objective determination and comparison of research performance. This paper aims to critically assess some standard bibliometric indicators commonly used (based on publication and citation counts) to evaluate academic units, and examine whether there…

  13. An Economist's View on Bibliometrically Measuring Scientific Research

    ERIC Educational Resources Information Center

    Veugelers, Reinhilde

    2005-01-01

    Since the use of bibliometric instruments has grown and will continue to grow in the future, the quality, availability, and accessibility of data on publications and citations is of tantamount importance. But equally important is a correct use of the data. This means that an important task of the bibliometric field is to highlight not only what…

  14. Facing Diversity of Science: A Challenge for Bibliometric Indicators

    ERIC Educational Resources Information Center

    Zitt, Michel

    2005-01-01

    Bibliometrics has come of age and is generally accepted, together with peer review, as one way to describe the activity of players in science. Appealing issues in bibliometrics include the characterization of a growth regime of research systems including the trade-offs of production-visibility; the measure of science-technology linkage and…

  15. The Simon-Yule Approach to Bibliometric Modeling.

    ERIC Educational Resources Information Center

    Chen, Ye-Sho; And Others

    1994-01-01

    Investigates the relationships between the parameters of the Simon-Yule model and the shapes of three bibliometric distributions: Lotka's Law of Scientific Productivity; Bradford's Law of Bibliometric Scattering; and Zipf's Law of Word Frequency. The results indicate that the probability of a new entry determines the characteristics of all three…

  16. Quantitative Proteomic Approaches for Studying Phosphotyrosine Signaling

    SciTech Connect

    Ding, Shi-Jian; Qian, Weijun; Smith, Richard D.

    2007-02-01

    Protein tyrosine phosphorylation is a fundamental mechanism for controlling many aspects of cellular processes, as well as aspects of human health and diseases. Compared to phosphoserine (pSer) and phosphothreonine (pThr), phosphotyrosine (pTyr) signaling is more tightly regulated, but often more challenging to characterize due to significantly lower level of tyrosine phosphorylation (a relative abundance of 1800:200:1 was estimated for pSer/pThr/pTyr in vertebrate cells[1]). In this review, we outline the recent advances in analytical methodologies for enrichment, identification, and accurate quantitation of tyrosine phosphorylated proteins and peptides using antibody-based technologies, capillary liquid chromatography (LC) coupled with mass spectrometry (MS), and various stable isotope labeling strategies, as well as non-MS-based methods such as protein or peptide array methods. These proteomic technological advances provide powerful tools for potentially understanding signal transduction at the system level and provide a basis for discovering novel drug targets for human diseases. [1] Hunter, T. (1998) The Croonian Lecture 1997. The phosphorylation of proteins on tyrosine: its role in cell growth and disease. Philos. Trans. R. Soc. Lond. B Biol. Sci. 353, 583–605

  17. Research on health inequalities: A bibliometric analysis (1966-2014).

    PubMed

    Bouchard, Louise; Albertini, Marcelo; Batista, Ricardo; de Montigny, Joanne

    2015-09-01

    The objective of this study is to report on research production and publications on health inequalities through a bibliometric analysis covering publications from 1966 to 2014 and a content analysis of the 25 most-cited papers. A database of 49,294 references was compiled from the search engine Web of Science. The first article appears in 1966 and deals with equality and civil rights in the United States and the elimination of racial discrimination in access to medical care. By 2003, the term disparity has gained in prominence relative to the term inequality which was initially elected by the researchers. Marmot's 1991 article is one of the five papers with the largest number of citations and contributes to the central perspective of social determinants of health and the British influence on the international status of research on social inequalities of health. PMID:26259012

  18. The Mozart Effect: A quantitative EEG study.

    PubMed

    Verrusio, Walter; Ettorre, Evaristo; Vicenzini, Edoardo; Vanacore, Nicola; Cacciafesta, Mauro; Mecarelli, Oriano

    2015-09-01

    The aim of this study is to investigate the influence of Mozart's music on brain activity through spectral analysis of the EEG in young healthy adults (Adults), in healthy elderly (Elderly) and in elderly with Mild Cognitive Impairment (MCI). EEG recording was performed at basal rest conditions and after listening to Mozart's K448 or "Fur Elise" Beethoven's sonatas. After listening to Mozart, an increase of alpha band and median frequency index of background alpha rhythm activity (a pattern of brain wave activity linked to memory, cognition and open mind to problem solving) was observed both in Adults and in Elderly. No changes were observed in MCI. After listening to Beethoven, no changes in EEG activity were detected. This results may be representative of the fact that said Mozart's music is able to "activate" neuronal cortical circuits related to attentive and cognitive functions. PMID:26036835

  19. Quantitative Proteomic Approaches to Studying Histone Modifications

    PubMed Central

    Zee, Barry M; Young, Nicolas L; Garcia, Benjamin A

    2011-01-01

    Histone post-translational modifications (PTMs) positively and negatively regulate gene expression, and are consequently a vital influence on the genomic profile of all eukaryotic species. The study of histone PTMs using classical methods in molecular biology, such as immunofluorescence and Western blotting, is challenging given the technical issues of the approaches, and chemical diversity and combinatorial patterns of the modifications. In light of these many technical limitations, mass spectrometry (MS) is emerging as the most unbiased and rigorous experimental platform to identify and quantify histone PTMs in a high-throughput manner. This review covers the latest developments in mass spectrometry for the analysis of histone PTMs, with the hope of inspiring the continued integration of proteomic, genomic and epigenetic research. PMID:21966350

  20. Research Review: Quantitative Magazine Studies, 1983-1993.

    ERIC Educational Resources Information Center

    Popovich, Mark N.

    1994-01-01

    Examines quantitative magazine research studies published in various journals during the period 1983-1993. Questions the heavy reliance on content analysis techniques to study the role of magazines in American society. Calls for a redirection in magazine research, combining media content studies with media effects studies. (SR)

  1. The APOSTEL recommendations for reporting quantitative optical coherence tomography studies

    PubMed Central

    Cruz-Herranz, Andrés; Balk, Lisanne J.; Oberwahrenbrock, Timm; Saidha, Shiv; Martinez-Lapiscina, Elena H.; Lagreze, Wolf A.; Schuman, Joel S.; Villoslada, Pablo; Calabresi, Peter; Balcer, Laura; Petzold, Axel; Green, Ari J.; Paul, Friedemann; Brandt, Alexander U.

    2016-01-01

    Objective: To develop consensus recommendations for reporting of quantitative optical coherence tomography (OCT) study results. Methods: A panel of experienced OCT researchers (including 11 neurologists, 2 ophthalmologists, and 2 neuroscientists) discussed requirements for performing and reporting quantitative analyses of retinal morphology and developed a list of initial recommendations based on experience and previous studies. The list of recommendations was subsequently revised during several meetings of the coordinating group. Results: We provide a 9-point checklist encompassing aspects deemed relevant when reporting quantitative OCT studies. The areas covered are study protocol, acquisition device, acquisition settings, scanning protocol, funduscopic imaging, postacquisition data selection, postacquisition data analysis, recommended nomenclature, and statistical analysis. Conclusions: The Advised Protocol for OCT Study Terminology and Elements recommendations include core items to standardize and improve quality of reporting in quantitative OCT studies. The recommendations will make reporting of quantitative OCT studies more consistent and in line with existing standards for reporting research in other biomedical areas. The recommendations originated from expert consensus and thus represent Class IV evidence. They will need to be regularly adjusted according to new insights and practices. PMID:27225223

  2. Music and Affective Phenomena: A 20-Year Content and Bibliometric Analysis of Research in Three Eminent Journals

    ERIC Educational Resources Information Center

    Diaz, Frank M.; Silveira, Jason M.

    2014-01-01

    The purpose of this study was to establish trends in the study of music and affective phenomena through a content and bibliometric analysis of three eminent music research journals, the "Journal of Research in Music Education", "Psychology of Music", and "Music Perception", for the years 1990 through 2009. Excluding…

  3. Microfluidics for High-Throughput Quantitative Studies of Early Development.

    PubMed

    Levario, Thomas J; Lim, Bomyi; Shvartsman, Stanislav Y; Lu, Hang

    2016-07-11

    Developmental biology has traditionally relied on qualitative analyses; recently, however, as in other fields of biology, researchers have become increasingly interested in acquiring quantitative knowledge about embryogenesis. Advances in fluorescence microscopy are enabling high-content imaging in live specimens. At the same time, microfluidics and automation technologies are increasing experimental throughput for studies of multicellular models of development. Furthermore, computer vision methods for processing and analyzing bioimage data are now leading the way toward quantitative biology. Here, we review advances in the areas of fluorescence microscopy, microfluidics, and data analysis that are instrumental to performing high-content, high-throughput studies in biology and specifically in development. We discuss a case study of how these techniques have allowed quantitative analysis and modeling of pattern formation in the Drosophila embryo. PMID:26928208

  4. Why Include Bibliometric Analysis in the Activities of a Library Specialized in Astronomy? — Notes From the Libraries of INTA

    NASA Astrophysics Data System (ADS)

    Alonso-Valdivielso, M. Á.; Antonio, E. G.

    2010-10-01

    We describe the different possibilities that several bibliometric studies offer the National Institute of Aerospace Technology (INTA) and the Center for Astrobiology (CAB) libraries. The main object in this paper is to show how the results of these investigations are useful for various matters, such as preservation options, exploitation and diffusion of these results, and facilitating internal information management.

  5. NASA Aeronautics and Space Database for bibliometric analysis

    NASA Technical Reports Server (NTRS)

    Powers, R.; Rudman, R.

    2004-01-01

    The authors use the NASA Aeronautics and Space Database to perform bibliometric analysis of citations. This paper explains their research methodology and gives some sample results showing collaboration trends between NASA Centers and other institutions.

  6. The Bibliometric Properties of Article Readership Information

    NASA Astrophysics Data System (ADS)

    Kurtz, Michael J.; Eichhorn, Guenther; Accomazzi, Alberto; Grant, Carolyn S.; Demleitner, Markus; Murray, Stephen S.; Martimbeau, Nathalie; Elwell, Barbara

    The NASA Astrophysics Data System (ADS), along with astronomy's journals and data centers (a collaboration dubbed URANIA), has developed a distributed on-line digital library which has become the dominant means by which astronomers search, access and read their technical literature. Digital libraries such as the NASA Astrophysics Data System \\citep{2005JASIS.tmp....2K} permit the easy accumulation of a new type of bibliometric measure, the number of electronic accesses (``reads'') of individual articles. We explore various aspects of this new measure. We examine the obsolescence function as measured by actual reads, and show that it can be well fit by the sum of four exponentials with very different time constants. We compare the obsolescence function as measured by readership with the obsolescence function as measured by citations. We find that the citation function is proportional to the sum of two of the components of the readership function. This proves that the normative theory of citation is true in the mean. We further examine in detail the similarities and differences between the citation rate, the readership rate and the total citations for individual articles, and discuss some of the causes. Using the number of reads as a bibliometric measure for individuals, we introduce the read-cite diagram to provide a two-dimensional view of an individual's scientific productivity. We develop a simple model to account for an individual's reads and cites and use it to show that the position of a person in the read-cite diagram is a function of age, innate productivity, and work history. We show the age biases of both reads and cites, and develop two new bibliometric measures which have substantially less age bias than citations: SumProd, a weighted sum of total citations and the readership rate, intended to show the total productivity of an individual; and Read10, the readership rate for papers published in the last ten years, intended to show an individual's current

  7. Metamorphism of eucrite meteorites studied quantitatively using induced thermoluminescence

    NASA Technical Reports Server (NTRS)

    Batchelor, J. David; Sears, Derek W. G.

    1991-01-01

    Induced thermoluminescence studies provide a new and quantitative means of determining relative metamorphic intensities for eucrite meteorites, the simplest and most ancient products of basaltic volcanism. Using this technique, it is shown that the eucrites constitute a continuous metamorphic series and not, as commonly assumed, two groups of metamorphosed and nonmetamorphosed meteorites. It is suggested that the method may have applications to other basalts.

  8. Retention of Nontraditional Students: A Quantitative Research Study

    ERIC Educational Resources Information Center

    Nichols, Shirley J.

    2009-01-01

    The purpose of this quantitative correlational research study was to investigate, describe, and measure factors influencing retention of nontraditional first and second year students at a university located in the Midwestern United States. Retention of adult students has become a major issue for many institutions of higher education and many…

  9. Employing quantitative and qualitative methods in one study.

    PubMed

    Mason, S A

    There is an apparent lack of epistemological rigour when quantitative and qualitative methods are combined in the same study, because they reflect opposing positivist and interpretive perspectives. When and how to use methodological pluralism is discussed in this article. PMID:8400784

  10. Quantitative methods for studying hemostasis in zebrafish larvae.

    PubMed

    Rost, M S; Grzegorski, S J; Shavit, J A

    2016-01-01

    Hemostasis is a coordinated system through which blood is prevented from exiting a closed circulatory system. We have taken advantage of the zebrafish, an emerging model for the study of blood coagulation, and describe three techniques for quantitative analysis of primary and secondary hemostasis. Collectively, these three techniques comprise a toolset to aid in our understanding of hemostasis and pathological clotting. PMID:27312499

  11. Comparative study of different venous reflux duplex quantitation parameters.

    PubMed

    Valentín, L I; Valentín, W H

    1999-09-01

    The objective of this study was to compare different quantitation parameters of venous reflux by duplex scan in different venous disease manifestations. Duplex scan is a new modality to quantify venous reflux. Several studies propose different parameters. In addition, there is controversy about the importance of deep and superficial involvement in different disease manifestations. It is not clear whether there is an increased venous reflux associated with varied clinical stages. Venous conditions were classified in seven stages and their differences for several quantitation variables studied. Most quantitation variables, such as average and peak velocity, average and peak flow, and reflux volume disclosed significantly increased reflux from normal, pain only, and edema group to varicose vein, with or without edema, to lipodermatosclerosis and ulcer groups at every location in the lower extremity. Reflux time was not as consistent as other variables. Totalization of the results of every parameter for the whole extremity points to an increased reflux from pain only to edema and from lipodermatosclerosis to ulcer group. Chronic edema is not usually associated with increased venous reflux. The greater saphenous vein (superficial system) seems to be the main contributor to reflux in all stages of disease. Different quantitation methods of venous reflux are equivalent. Increased deep and superficial reflux and its totalization are associated with a more advanced disease stage. Reflux time may be the least useful variable. Chronic edema is frequently not associated with venous reflux. Greater saphenectomy may be the most useful intervention, even in the presence of deep vein reflux. PMID:10496498

  12. Study on the performance evaluation of quantitative precipitation estimation and quantitative precipitation forecast

    NASA Astrophysics Data System (ADS)

    Yang, H.; Chang, K.; Suk, M.; cha, J.; Choi, Y.

    2011-12-01

    Rainfall estimation and short-term (several hours) quantitative prediction of precipitation based on meteorological radar data is one of the intensely studied topics. The Korea Peninsula has the horizontally narrow land area and complex topography with many of mountains, and so it has the characteristics that the rainfall system changes in many cases. Quantitative precipitation estimation (QPE) and quantitative precipitation forecasts (QPF) are the crucial information for severe weather or water management. We have been conducted the performance evaluation of QPE/QPF of Korea Meteorological Administration (KMA), which is the first step for optimizing QPE/QPF system in South Korea. The real-time adjusted RAR (Radar-AWS-Rainrate) system gives better agreement with the observed rain-rate than that of the fixed Z-R relation, and the additional bias correction of RAR yields the slightly better results. A correlation coefficient of R2 = 0.84 is obtained between the daily accumulated observed and RAR estimated rainfall. The RAR will be available for the hydrological applications such as the water budget. The VSRF (Very Short Range Forecast) shows better performance than the MAPLE (McGill Algorithm for Precipitation Nowcasting by Lagrangian) within 40 minutes, but the MAPLE better than the VSRF after 40 minutes. In case of hourly forecast, MAPLE shows better performance than the VSRF. QPE and QPF are thought to be meaningful for the nowcasting (1~2 hours) except the model forecast. The long-term forecast longer than 3 hours by meteorological model is especially meaningful for such as water management.

  13. Splash erosion. A bibliometric Review

    NASA Astrophysics Data System (ADS)

    Fernández Raga, M. B.

    2012-04-01

    Ellison (1944) developed the splash board as a system for measuring splash erosion that was both cheap and reliable. Bollinne (1975), Morgan (1978, 1981). Mutchler (1967) described another different type of splash detectors according to whether they were passive or could register data. In the study mentioned above these authors included bottles, funnels, glasses, photography, markers. After that several devices has been made up like the splash sampler (Leguedois et al., 2005), soil tray (Van Dijk et al., 2002), splash funnel (Terry, 1989) and several rain cups (Fernandez-Raga et al., 2010; Molina and Llinares, 1996; Torri et al., 1987). Splash erosion research has materialized in the form of a number of papers published in international journals. The database of bibliographic references employed has been one of the most prestigious ones: theWeb of Science (ISI). The search was carried out on January 27th 2012. Among the 3x10^8 scholarly documents included in the Science Citation Index Expanded (SCI-EXPANDED) 1899 to present , the searching engine located 439 containing the word "splash erosion*", where the asterisk acts as a wildcard for any letter or group of letters. Of these, 383 were classified as articles, 87 as proceeding papers, 5 as editorial material, 2 as notes and 1 as correction. These documents have been published in 163 different journals, although four are particularly recurrent: Earth surface processes and Landforms, Catena, Soil Science Society of America Journal and Hydrological processes, with 41, 35, 35 and 26 published documents respectively. A geographic analysis of these articles has been carried out in an attempt to determine in what parts of the world research projects were making use of splash erosion. The results are that anglo-saxon countries, as USA, England and Australia dominate, particularly USA, with 130 articles. China and Japan are large communities of researches too, and some Central European countries as Belgium, France Germany

  14. Bibliometrics Course Offerings by Library and Information Science Programs in China

    ERIC Educational Resources Information Center

    Xiao, Ming; Zhao, Dangzhi; Yin, Yali; Yu, Jia

    2016-01-01

    In this article, we report results from a survey of bibliometrics courses offered by LIS programs in mainland China. We found that more than 27% of Chinese LIS programs offer bibliometrics courses. The majority of these programs teach bibliometrics as 2- or 3-credit, required courses to both undergraduate and graduate students, indicating the…

  15. How Implementation of Bibliometric Practice Affects the Role of Academic Libraries

    ERIC Educational Resources Information Center

    Åström, Fredrik; Hansson, Joacim

    2013-01-01

    This article discusses potential consequences of implementing bibliometrics as an institutionalized practice in academic libraries. Results are reported from a survey among libraries in Sweden with organized bibliometric activities. Incorporating bibliometric activities is one way of redefining and widening the role of the library. Implementation…

  16. Nuclear medicine and imaging research: Quantitative studies in radiopharmaceutical science

    SciTech Connect

    Copper, M.; Beck, R.N.

    1991-06-01

    During the past three years the program has undergone a substantial revitalization. There has been no significant change in the scientific direction of this grant, in which emphasis continues to be placed on developing new or improved methods of obtaining quantitative data from radiotracer imaging studies. However, considerable scientific progress has been made in the three areas of interest: Radiochemistry, Quantitative Methodologies, and Experimental Methods and Feasibility Studies, resulting in a sharper focus of perspective and improved integration of the overall scientific effort. Changes in Faculty and staff, including development of new collaborations, have contributed to this, as has acquisition of additional and new equipment and renovations and expansion of the core facilities. 121 refs., 30 figs., 2 tabs.

  17. Calibration assessment in quantitative electroencephalographic brainmapping and evoked potential studies.

    PubMed

    Richards, A K; Hamilton-Bruce, M A

    1994-09-01

    Acquisition of a Cadwell Spectrum 32 resulted in the introduction of quantitative electrophysiological brainmapping techniques in our neurophysiology laboratory. To ascertain the accuracy and consistency of our equipment, we performed the following tests: inputting a calibration signal and measuring the resultant amplitudes for quantitative electroencephalographs (qEEGs) and evoked potentials (EPs) in the mapping and standard montages, inputting a synchronous calibration signal and mapping it at varying times for qEEGs and EPs, as well as re-analysing the same electroencephalographic (EEG) epochs previously selected from 20 control subjects. QEEG amplitudes varied from -5.4% to +5.8% and EPs by 9.5% or less, and after an EP software upgrade, by 5.5% or less. QEEG voltage mapping showed variation of only one color increment across the map, which could, in our example, represent up to 25.2% of the scale used. Re-analysis of previously selected epochs yielded identical results. We have established some of the accuracy and consistency limits of the hard- and software of our system with respect to the quantitative and topographic data. We conclude that such systems need to be calibration-checked in the laboratories in which they are used, with an independent signal generator. Users also need to be aware that scaling of topographic maps could lead to erroneous conclusions, as perceived amplitude changes could affect the interpretation of both initial and serial studies. PMID:7980205

  18. Progress and Prospect: A Bibliometric Analysis of Research Papers by Korean Allergists Over Recent Five Years (2009-2013)

    PubMed Central

    Song, Woo-Jung; Jee, Hye Mi; Suh, Dong In; Yang, Hyeon-Jong; Yoon, Jong-seo; Yu, Jinho; Kim, Sang-Heon; Ye, Young-Min; Kim, Tae-Bum; Shin, Seung Youp; Li, Kapsok

    2015-01-01

    Since the establishment of the academic society in 1972, Korean allergists have made continuous efforts to elucidate pathogenic mechanisms and therapeutic advances for allergic diseases. The present study aimed to summarize recent progress and explore future prospects of research performance by Korean allergists. We performed a comprehensive bibliometric analysis for research papers published in the Science Citation Index (SCI) or SCI-expanded journals by Korean allergists between 2009 and 2013. Research performance was quantitatively analyzed for the numbers of papers by publication year, research type, and main topic. In addition, the performance was also examined for qualitative indices, such as impact factor and citation number. A total of 1,091 papers were identified. The number of publication increased continuously, with an annual increase rate of 12.3%. Clinical and basic studies were the most frequent types of research, and recently the number of epidemiological studies has increased. By research topic, asthma was the most commonly studied, accounting for 20.9% of the total number of publications. Notably, the amount of rhinitis/rhinosinusitis research has risen steeply in 2013. Qualitative analyses also indicated continuous progress; the median impact factor of published journals increased from 1.918 in 2009 to 2.746 in 2013, yielding an annual increase rate of 7.4%. In conclusion, the present analyses identified a continuous increase in the research performance of Korean allergists over a recent 5 year period (2009-2013), both quantitatively and qualitatively. A more significant contribution is expected in the forthcoming era. PMID:26122510

  19. Progress and Prospect: A Bibliometric Analysis of Research Papers by Korean Allergists Over Recent Five Years (2009-2013).

    PubMed

    Song, Woo Jung; Jee, Hye Mi; Suh, Dong In; Yang, Hyeon Jong; Yoon, Jong Seo; Yu, Jinho; Kim, Sang Heon; Ye, Young Min; Kim, Tae Bum; Shin, Seung Youp; Li, Kapsok; Kim, Cheol Woo

    2015-09-01

    Since the establishment of the academic society in 1972, Korean allergists have made continuous efforts to elucidate pathogenic mechanisms and therapeutic advances for allergic diseases. The present study aimed to summarize recent progress and explore future prospects of research performance by Korean allergists. We performed a comprehensive bibliometric analysis for research papers published in the Science Citation Index (SCI) or SCI-expanded journals by Korean allergists between 2009 and 2013. Research performance was quantitatively analyzed for the numbers of papers by publication year, research type, and main topic. In addition, the performance was also examined for qualitative indices, such as impact factor and citation number. A total of 1,091 papers were identified. The number of publication increased continuously, with an annual increase rate of 12.3%. Clinical and basic studies were the most frequent types of research, and recently the number of epidemiological studies has increased. By research topic, asthma was the most commonly studied, accounting for 20.9% of the total number of publications. Notably, the amount of rhinitis/rhinosinusitis research has risen steeply in 2013. Qualitative analyses also indicated continuous progress; the median impact factor of published journals increased from 1.918 in 2009 to 2.746 in 2013, yielding an annual increase rate of 7.4%. In conclusion, the present analyses identified a continuous increase in the research performance of Korean allergists over a recent 5 year period (2009-2013), both quantitatively and qualitatively. A more significant contribution is expected in the forthcoming era. PMID:26122510

  20. Quantitative study of protein-protein interactions by quartz nanopipettes

    NASA Astrophysics Data System (ADS)

    Tiwari, Purushottam Babu; Astudillo, Luisana; Miksovska, Jaroslava; Wang, Xuewen; Li, Wenzhi; Darici, Yesim; He, Jin

    2014-08-01

    In this report, protein-modified quartz nanopipettes were used to quantitatively study protein-protein interactions in attoliter sensing volumes. As shown by numerical simulations, the ionic current through the conical-shaped nanopipette is very sensitive to the surface charge variation near the pore mouth. With the appropriate modification of negatively charged human neuroglobin (hNgb) onto the inner surface of a nanopipette, we were able to detect concentration-dependent current change when the hNgb-modified nanopipette tip was exposed to positively charged cytochrome c (Cyt c) with a series of concentrations in the bath solution. Such current change is due to the adsorption of Cyt c to the inner surface of the nanopipette through specific interactions with hNgb. In contrast, a smaller current change with weak concentration dependence was observed when Cyt c was replaced with lysozyme, which does not specifically bind to hNgb. The equilibrium dissociation constant (KD) for the Cyt c-hNgb complex formation was derived and the value matched very well with the result from surface plasmon resonance measurement. This is the first quantitative study of protein-protein interactions by a conical-shaped nanopore based on charge sensing. Our results demonstrate that nanopipettes can potentially be used as a label-free analytical tool to quantitatively characterize protein-protein interactions.In this report, protein-modified quartz nanopipettes were used to quantitatively study protein-protein interactions in attoliter sensing volumes. As shown by numerical simulations, the ionic current through the conical-shaped nanopipette is very sensitive to the surface charge variation near the pore mouth. With the appropriate modification of negatively charged human neuroglobin (hNgb) onto the inner surface of a nanopipette, we were able to detect concentration-dependent current change when the hNgb-modified nanopipette tip was exposed to positively charged cytochrome c (Cyt c) with

  1. Quantitative Courses in a Liberal Education Program: A Case Study

    ERIC Educational Resources Information Center

    Wismath, Shelly L.; Mackay, D. Bruce

    2012-01-01

    This essay argues for the importance of quantitative reasoning skills as part of a liberal education and describes the successful introduction of a mathematics-based quantitative skills course at a small Canadian university. Today's students need quantitative problem-solving skills, to function as adults, professionals, consumers, and citizens in…

  2. A quantitative study of oxygen as a metabolic regulator

    NASA Technical Reports Server (NTRS)

    Radhakrishnan, Krishnan; LaManna, Joseph C.; Cabrera, Marco E.

    2003-01-01

    An acute reduction in oxygen delivery to a tissue is associated with metabolic changes aimed at maintaining ATP homeostasis. However, given the complexity of the human bioenergetic system, it is difficult to determine quantitatively how cellular metabolic processes interact to maintain ATP homeostasis during stress (e.g., hypoxia, ischemia, and exercise). In particular, we are interested in determining mechanisms relating cellular oxygen concentration to observed metabolic responses at the cellular, tissue, organ, and whole body levels and in quantifying how changes in tissue oxygen availability affect the pathways of ATP synthesis and the metabolites that control these pathways. In this study, we extend a previously developed mathematical model of human bioenergetics, to provide a physicochemical framework that permits quantitative understanding of oxygen as a metabolic regulator. Specifically, the enhancement--sensitivity analysis--permits studying the effects of variations in tissue oxygenation and parameters controlling cellular respiration on glycolysis, lactate production, and pyruvate oxidation. The analysis can distinguish between parameters that must be determined accurately and those that require less precision, based on their effects on model predictions. This capability may prove to be important in optimizing experimental design, thus reducing use of animals.

  3. A Quantitative Study of Oxygen as a Metabolic Regulator

    NASA Technical Reports Server (NTRS)

    Radhakrishnan, Krishnan; LaManna, Joseph C.; Cabera, Marco E.

    2000-01-01

    An acute reduction in oxygen delivery to a tissue is associated with metabolic changes aimed at maintaining ATP homeostasis. However, given the complexity of the human bio-energetic system, it is difficult to determine quantitatively how cellular metabolic processes interact to maintain ATP homeostasis during stress (e.g., hypoxia, ischemia, and exercise). In particular, we are interested in determining mechanisms relating cellular oxygen concentration to observed metabolic responses at the cellular, tissue, organ, and whole body levels and in quantifying how changes in tissue oxygen availability affect the pathways of ATP synthesis and the metabolites that control these pathways. In this study; we extend a previously developed mathematical model of human bioenergetics, to provide a physicochemical framework that permits quantitative understanding of oxygen as a metabolic regulator. Specifically, the enhancement - sensitivity analysis - permits studying the effects of variations in tissue oxygenation and parameters controlling cellular respiration on glycolysis, lactate production, and pyruvate oxidation. The analysis can distinguish between parameters that must be determined accurately and those that require less precision, based on their effects on model predictions. This capability may prove to be important in optimizing experimental design, thus reducing use of animals.

  4. A descriptive and historical review of bibliometrics with applications to medical sciences.

    PubMed

    Thompson, Dennis F; Walker, Cheri K

    2015-06-01

    The discipline of bibliometrics involves the application of mathematical and statistical methods to scholarly publications. The first attempts at systematic data collection were provided by Alfred Lotka and Samuel Bradford, who subsequently established the foundational laws of bibliometrics. Eugene Garfield ushered in the modern era of bibliometrics with the routine use of citation analysis and systematized processing. Key elements of bibliometric analysis include database coverage, consistency and accuracy of the data, data fields, search options, and analysis and use of metrics. A number of bibliometric applications are currently being used in medical science and health care. Bibliometric parameters and indexes may be increasingly used by grant funding sources as measures of research success. Universities may build benchmarking standards from bibliometric data to determine academic achievement through promotion and tenure guidelines in the future. This article reviews the history, definition, laws, and elements of bibliometric principles and provides examples of bibliometric applications to the broader health care community. To accomplish this, the Medline (1966-2014) and Web of Science (1945-2014) databases were searched to identify relevant articles; select articles were also cross-referenced. Articles selected were those that provided background, history, descriptive analysis, and application of bibliometric principles and metrics to medical science and health care. No attempt was made to cover all areas exhaustively; rather, key articles were chosen that illustrate bibliometric concepts and enhance the reader's knowledge. It is important that faculty and researchers understand the limitations and appropriate uses of bibliometric data. Bibliometrics has considerable potential as a research area for health care scientists and practitioners that can be used to discover new information about academic trends, pharmacotherapy, disease, and broader health sciences

  5. Nuclear medicine and imaging research (quantitative studies in radiopharmaceutical science)

    SciTech Connect

    Cooper, M.D.; Beck, R.N.

    1990-09-01

    This is a report of progress in Year Two (January 1, 1990--December 31, 1990) of Grant FG02-86ER60438, Quantitative Studies in Radiopharmaceutical Science,'' awarded for the three-year period January 1, 1989--December 31, 1991 as a competitive renewal following site visit in the fall of 1988. This program addresses the problems involving the basic science and technology underlying the physical and conceptual tools of radioactive tracer methodology as they relate to the measurement of structural and functional parameters of physiologic importance in health and disease. The principal tool is quantitative radionuclide imaging. The overall objective of this program is to further the development and transfer of radiotracer methodology from basic theory to routine clinical practice in order that individual patients and society as a whole will receive the maximum net benefit from the new knowledge gained. The focus of the research is on the development of new instruments and radiopharmaceuticals, and the evaluation of these through the phase of clinical feasibility. 25 refs., 13 figs., 1 tab.

  6. Quantitative analysis of multiple sclerosis: a feasibility study

    NASA Astrophysics Data System (ADS)

    Li, Lihong; Li, Xiang; Wei, Xinzhou; Sturm, Deborah; Lu, Hongbing; Liang, Zhengrong

    2006-03-01

    Multiple Sclerosis (MS) is an inflammatory and demyelinating disorder of the central nervous system with a presumed immune-mediated etiology. For treatment of MS, the measurements of white matter (WM), gray matter (GM), and cerebral spinal fluid (CSF) are often used in conjunction with clinical evaluation to provide a more objective measure of MS burden. In this paper, we apply a new unifying automatic mixture-based algorithm for segmentation of brain tissues to quantitatively analyze MS. The method takes into account the following effects that commonly appear in MR imaging: 1) The MR data is modeled as a stochastic process with an inherent inhomogeneity effect of smoothly varying intensity; 2) A new partial volume (PV) model is built in establishing the maximum a posterior (MAP) segmentation scheme; 3) Noise artifacts are minimized by a priori Markov random field (MRF) penalty indicating neighborhood correlation from tissue mixture. The volumes of brain tissues (WM, GM) and CSF are extracted from the mixture-based segmentation. Experimental results of feasibility studies on quantitative analysis of MS are presented.

  7. Quantitative study on appearance of microvessels in spectral endoscopic imaging

    NASA Astrophysics Data System (ADS)

    Yamaguchi, Hiroshi; Saito, Takaaki; Shiraishi, Yasushi; Arai, Fumihito; Morimoto, Yoshinori; Yuasa, Atsuko

    2015-03-01

    Increase in abnormal microvessels in the superficial mucosa is often relevant to diagnostic findings of neoplasia in digestive endoscopy; hence, observation of superficial vasculature is crucial for cancer diagnosis. To enhance the appearance of such vessels, several spectral endoscopic imaging techniques have been developed, such as narrow-band imaging and blue laser imaging. Both techniques exploit narrow-band blue light for the enhancement. The emergence of such spectral imaging techniques has increased the importance of understanding the relation of the light wavelength to the appearance of superficial vasculature, and thus a new method is desired for quantitative analysis of vessel visibility in relation to the actual structure in the tissue. Here, we developed microvessel-simulating phantoms that allowed quantitative evaluation of the appearance of 15-μm-thick vessels. We investigated the relation between the vascular contrast and light wavelength by the phantom measurements and also verified it in experiments with swine, where the endoscopically observed vascular contrast was investigated together with its real vascular depth and diameter obtained by microscopic observation of fluorescence-labeled vessels. Our study indicates that changing the spectral property even in the wavelength range of blue light may allow selective enhancement of the vascular depth for clinical use.

  8. "Library Quarterly," 1956-2004: An Exploratory Bibliometric Analysis

    ERIC Educational Resources Information Center

    Young, Arthur P.

    2006-01-01

    "Library Quarterly's" seventy-fifth anniversary invites an analysis of the journal's bibliometric dimension, including contributor attributes, various author rankings, and citation impact. Eugene Garfield's HistCite software, linked to Thomson Scientific's Web of Science, as made available by Garfield, for the period 1956-2004, was used as the…

  9. Bibliometric Modeling Processes and the Empirical Validity of Lotka's Law.

    ERIC Educational Resources Information Center

    Nicholls, Paul Travis

    1989-01-01

    Examines the elements involved in fitting a bibliometric model to empirical data, proposes a consistent methodology for applying Lotka's law, and presents the results of an empirical test of the methodology. The results are discussed in terms of the validity of Lotka's law and the suitability of the proposed methodology. (49 references) (CLB)

  10. A Bibliometric Analysis of Marriage and Family Literature.

    ERIC Educational Resources Information Center

    Bayer, Alan E.

    1982-01-01

    Demonstrated that several quantifiable characteristics of articles in the marriage and family area are substantially related to subsequent impact in the field, based on bibliometric citation analysis. Works published by the more eminent, highly cited scholars are more likely to be cited. Implications of these results are discussed. (Author)

  11. Hypersonic and Supersonic Flow Roadmaps Using Bibliometrics and Database Tomography.

    ERIC Educational Resources Information Center

    Kostoff, R. N.; Eberhart, Henry J.; Toothman, Darrell Ray

    1999-01-01

    Database Tomography (DT) is a textual database-analysis system consisting of algorithms for extracting multiword phrase frequencies and proximities from a large textual database, to augment interpretative capabilities of the expert human analyst. Describes use of the DT process, supplemented by literature bibliometric analyses, to derive technical…

  12. A Bibliometric Analysis of Certain Information Science Literature

    ERIC Educational Resources Information Center

    Donohue, Joseph C.

    1972-01-01

    Several bibliometric techniques previously applied to separate scientific literatures were used together in the analysis of a single corpus of journal articles relating to information science. Techniques included were: Bradford Analysis, epidemic analysis, identification of research front, and bibliographic coupling. (16 references) (Author)

  13. Phelan's Bibliometric Analysis of the Impact of Australian Educational Research

    ERIC Educational Resources Information Center

    Bates, Richard

    2003-01-01

    Phelan (2000) has produced a complex bibliometric analysis of the international contribution of Australian educational research based upon publications and citations reported in the journals indexed by the Institute for Scientific Information--the Standard & Poors of the academic world. This paper examines Phelan's analysis, showing its strengths…

  14. Motor Events during Healthy Sleep: A Quantitative Polysomnographic Study

    PubMed Central

    Frauscher, Birgit; Gabelia, David; Mitterling, Thomas; Biermayr, Marlene; Bregler, Deborah; Ehrmann, Laura; Ulmer, Hanno; Högl, Birgit

    2014-01-01

    Study Objectives: Many sleep disorders are characterized by increased motor activity during sleep. In contrast, studies on motor activity during physiological sleep are largely lacking. We quantitatively investigated a large range of motor phenomena during polysomnography in physiological sleep. Design: Prospective polysomnographic investigation. Setting: Academic referral sleep laboratory. Participants: One hundred healthy sleepers age 19-77 y were strictly selected from a representative population sample by a two-step screening procedure. Interventions: N/A. Measurements and Results: Polysomnography according to American Academy of Sleep Medicine (AASM) standards was performed, and quantitative normative values were established for periodic limb movements in sleep (PLMS), high frequency leg movements (HFLM), fragmentary myoclonus (FM), neck myoclonus (NM), and rapid eye movement (REM)-related electromyographic (EMG) activity. Thirty-six subjects had a PLMS index > 5/h, 18 had a PLMS index > 15/h (90th percentile: 24.8/h). Thirty-three subjects had HFLM (90th percentile: four sequences/night). All subjects had FM (90th percentile 143.7/h sleep). Nine subjects fulfilled AASM criteria for excessive FM. Thirty-five subjects had NM (90th percentile: 8.8/h REM sleep). For REM sleep, different EMG activity measures for the mentalis and flexor digitorum superficialis muscles were calculated: the 90th percentile for phasic mentalis EMG activity for 30-sec epochs according to AASM recommendation was 15.6%, and for tonic mentalis EMG activity 2.6%. Twenty-five subjects exceeded the recently proposed phasic mentalis cutoff of 11%. None of the subjects exceeded the tonic mentalis cutoff of 9.6%. Conclusion: Quantification of motor phenomena is a basic prerequisite to develop normative values, and is a first step toward a more precise description of the various motor phenomena present during sleep. Because rates of motor events were unexpectedly high even in physiological

  15. Quantitative structure-activity studies on monoamine oxidase inhibitors.

    PubMed

    Johnson, C L

    1976-05-01

    Quantitative structure-activity studies were carried out on a series of N-isopropylaryl hydrazides which inhibits monoamine oxidase (MAO). The inhibitory potencies of these compounds of MAO were found to correlate with the electron-withdrawing capacity of the aryl ring substituents as estimated by both empirical Hammet sigma constants and electronic indices from molecular orbital calculations. Based on these correlations and previously published data on other classes of MAO inhibitors, a general model for the inhibitor pharmacophore is proposed: potent MAO of an aromatic ring; electron-withdrawing groups on the aromatic ring or replacing the phenyl ring with certain types of heterocyclic rings will tend to increase the potency. PMID:1271400

  16. The Evolution of Recent Research on Catalan Literature through the Production of PhD Theses: A Bibliometric and Social Network Analysis

    ERIC Educational Resources Information Center

    Ardanuy, Jordi; Urbano, Cristobal; Quintana, Lluis

    2009-01-01

    Introduction: This paper studies the situation of research on Catalan literature between 1976 and 2003 by carrying out a bibliometric and social network analysis of PhD theses defended in Spain. It has a dual aim: to present interesting results for the discipline and to demonstrate the methodological efficacy of scientometric tools in the…

  17. Quantitative methods in the study of trypanosomes and their applications*

    PubMed Central

    Lumsden, W. H. R.

    1963-01-01

    In the first part of this paper the author summarizes and discusses previous quantitative work on trypanosomes, with particular reference to biometrical studies, in vivo and in vitro studies on numbers of trypanosomes, studies on hosts infected with trypanosomes, and physiological studies. The second part discusses recent work done at the East African Trypanosomiasis Research Organization. A method for the measurement of the infectivity of trypanosome suspensions, based on serial dilution and inoculation into test animals, is outlined, and applications likely to improve diagnostic procedures are suggested for it. Such applications might include: the establishment of experimental procedures not significantly reducing the infectivity of trypanosomes under experiment; determination of the effects on the infectivity of preserved material of some of the factors in the process of preservation, important for the preparation of standard material; comparison of the efficiency of different culture media for the isolation of trypanosomes; study of the distribution of trypanosomes in the vertebrate host; and measurement of the susceptibility of trypanosomes to drugs. The author stresses the importance of relating future experimental work with trypanosomes to preserved material for which comprehensive documentation is available. PMID:20604152

  18. A study on the quantitative evaluation of skin barrier function

    NASA Astrophysics Data System (ADS)

    Maruyama, Tomomi; Kabetani, Yasuhiro; Kido, Michiko; Yamada, Kenji; Oikaze, Hirotoshi; Takechi, Yohei; Furuta, Tomotaka; Ishii, Shoichi; Katayama, Haruna; Jeong, Hieyong; Ohno, Yuko

    2015-03-01

    We propose a quantitative evaluation method of skin barrier function using Optical Coherence Microscopy system (OCM system) with coherency of near-infrared light. There are a lot of skin problems such as itching, irritation and so on. It has been recognized skin problems are caused by impairment of skin barrier function, which prevents damage from various external stimuli and loss of water. To evaluate skin barrier function, it is a common strategy that they observe skin surface and ask patients about their skin condition. The methods are subjective judgements and they are influenced by difference of experience of persons. Furthermore, microscopy has been used to observe inner structure of the skin in detail, and in vitro measurements like microscopy requires tissue sampling. On the other hand, it is necessary to assess objectively skin barrier function by quantitative evaluation method. In addition, non-invasive and nondestructive measuring method and examination changes over time are needed. Therefore, in vivo measurements are crucial for evaluating skin barrier function. In this study, we evaluate changes of stratum corneum structure which is important for evaluating skin barrier function by comparing water-penetrated skin with normal skin using a system with coherency of near-infrared light. Proposed method can obtain in vivo 3D images of inner structure of body tissue, which is non-invasive and non-destructive measuring method. We formulate changes of skin ultrastructure after water penetration. Finally, we evaluate the limit of performance of the OCM system in this work in order to discuss how to improve the OCM system.

  19. Quantitative error analysis for computer assisted navigation: a feasibility study

    PubMed Central

    Güler, Ö.; Perwög, M.; Kral, F.; Schwarm, F.; Bárdosi, Z. R.; Göbel, G.; Freysinger, W.

    2013-01-01

    Purpose The benefit of computer-assisted navigation depends on the registration process, at which patient features are correlated to some preoperative imagery. The operator-induced uncertainty in localizing patient features – the User Localization Error (ULE) - is unknown and most likely dominating the application accuracy. This initial feasibility study aims at providing first data for ULE with a research navigation system. Methods Active optical navigation was done in CT-images of a plastic skull, an anatomic specimen (both with implanted fiducials) and a volunteer with anatomical landmarks exclusively. Each object was registered ten times with 3, 5, 7, and 9 registration points. Measurements were taken at 10 (anatomic specimen and volunteer) and 11 targets (plastic skull). The active NDI Polaris system was used under ideal working conditions (tracking accuracy 0.23 mm root mean square, RMS; probe tip calibration was 0.18 mm RMS. Variances of tracking along the principal directions were measured as 0.18 mm2, 0.32 mm2, and 0.42 mm2. ULE was calculated from predicted application accuracy with isotropic and anisotropic models and from experimental variances, respectively. Results The ULE was determined from the variances as 0.45 mm (plastic skull), 0.60 mm (anatomic specimen), and 4.96 mm (volunteer). The predicted application accuracy did not yield consistent values for the ULE. Conclusions Quantitative data of application accuracy could be tested against prediction models with iso- and anisotropic noise models and revealed some discrepancies. This could potentially be due to the facts that navigation and one prediction model wrongly assume isotropic noise (tracking is anisotropic), while the anisotropic noise prediction model assumes an anisotropic registration strategy (registration is isotropic in typical navigation systems). The ULE data are presumably the first quantitative values for the precision of localizing anatomical landmarks and implanted fiducials

  20. ABRF-PRG07: Advanced Quantitative Proteomics Study

    PubMed Central

    Falick, Arnold M.; Lane, William S.; Lilley, Kathryn S.; MacCoss, Michael J.; Phinney, Brett S.; Sherman, Nicholas E.; Weintraub, Susan T.; Witkowska, H. Ewa; Yates, Nathan A.

    2011-01-01

    A major challenge for core facilities is determining quantitative protein differences across complex biological samples. Although there are numerous techniques in the literature for relative and absolute protein quantification, the majority is nonroutine and can be challenging to carry out effectively. There are few studies comparing these technologies in terms of their reproducibility, accuracy, and precision, and no studies to date deal with performance across multiple laboratories with varied levels of expertise. Here, we describe an Association of Biomolecular Resource Facilities (ABRF) Proteomics Research Group (PRG) study based on samples composed of a complex protein mixture into which 12 known proteins were added at varying but defined ratios. All of the proteins were present at the same concentration in each of three tubes that were provided. The primary goal of this study was to allow each laboratory to evaluate its capabilities and approaches with regard to: detection and identification of proteins spiked into samples that also contain complex mixtures of background proteins and determination of relative quantities of the spiked proteins. The results returned by 43 participants were compiled by the PRG, which also collected information about the strategies used to assess overall performance and as an aid to development of optimized protocols for the methodologies used. The most accurate results were generally reported by the most experienced laboratories. Among laboratories that used the same technique, values that were closer to the expected ratio were obtained by more experienced groups. PMID:21455478

  1. A Quantitative Study of Oxygen as a Metabolic Regulator

    NASA Technical Reports Server (NTRS)

    Radhakrishnan, Krishnan; LaManna, Joseph C.; Cabrera, Marco E.

    1999-01-01

    An acute reduction in oxygen (O2) delivery to a tissue is generally associated with a decrease in phosphocreatine, increases in ADP, NADH/NAD, and inorganic phosphate, increased rates of glycolysis and lactate production, and reduced rates of pyruvate and fatty acid oxidation. However, given the complexity of the human bioenergetic system and its components, it is difficult to determine quantitatively how cellular metabolic processes interact to maintain ATP homeostasis during stress (e.g., hypoxia, ischemia, and exercise). Of special interest is the determination of mechanisms relating tissue oxygenation to observed metabolic responses at the tissue, organ, and whole body levels and the quantification of how changes in tissue O2 availability affect the pathways of ATP synthesis and the metabolites that control these pathways. In this study, we extend a previously developed mathematical model of human bioenergetics to provide a physicochemical framework that permits quantitative understanding of O2 as a metabolic regulator. Specifically, the enhancement permits studying the effects of variations in tissue oxygenation and in parameters controlling the rate of cellular respiration on glycolysis, lactate production, and pyruvate oxidation. The whole body is described as a bioenergetic system consisting of metabolically distinct tissue/organ subsystems that exchange materials with the blood. In order to study the dynamic response of each subsystem to stimuli, we solve the ordinary differential equations describing the temporal evolution of metabolite levels, given the initial concentrations. The solver used in the present study is the packaged code LSODE, as implemented in the NASA Lewis kinetics and sensitivity analysis code, LSENS. A major advantage of LSENS is the efficient procedures supporting systematic sensitivity analysis, which provides the basic methods for studying parameter sensitivities (i.e., changes in model behavior due to parameter variation

  2. Bibliometrics of NIHR HTA monographs and their related journal articles

    PubMed Central

    Royle, Pamela

    2015-01-01

    Objectives A bibliometric analysis of the UK National Institute for Health Research (NIHR) Health Technology Assessment (HTA) monographs and their related journal articles by: (1) exploring the differences in citations to the HTA monographs in Google Scholar (GS), Scopus and Web of Science (WoS), and (2) comparing Scopus citations to the monographs with their related journal articles. Setting A study of 111 HTA monographs published in 2010 and 2011, and their external journal articles. Main outcome measures Citations to the monographs in GS, Scopus and WoS, and to their external journal articles in Scopus. Results The number of citations varied among the three databases, with GS having the highest and WoS the lowest; however, the citation-based rankings among the databases were highly correlated. Overall, 56% of monographs had a related publication, with the highest proportion for primary research (76%) and lowest for evidence syntheses (43%). There was a large variation in how the monographs were cited, compared to journal articles, resulting in more frequent problems, with unlinked citations in Scopus and WoS. When comparing differences in the number of citations between monograph publications with their related journal articles from the same project, we found that monographs received more citations than their journal articles for evidence syntheses and methodology projects; by contrast, journal articles related to primary research monographs were more highly cited than their monograph. Conclusions The numbers of citations to the HTA monographs differed considerably between the databases, but were highly correlated. When a HTA monograph had a journal article from the same study, there were more citations to the journal article for primary research, but more to the monographs for evidence syntheses. Citations to the related journal articles were more reliably recorded than citations to the HTA monographs. PMID:25694457

  3. 25 years of telepathology research: a bibliometric analysis

    PubMed Central

    2011-01-01

    Background The first appearance of the word “telepathology” in a scientific paper can be tracked down to 1986, in a famous editorial of Ronald Weinstein. Since that paper, research in telepathology grew up developing different subfields, including static and dynamic telepathology and more recently virtual microscopy. The present work attempts an analysis of research in telepathology, starting from the tools provided by bibliometrics. Methods A query has been developed to extract papers related to telepathology and virtual microscopy, and it has been then submitted to Pubmed by means of Entrez Utilities functions. Results obtained in XML have been processed through ad-hoc developed PHP scripts, in order to extract data on Authors, countries, and keywords. Results On PubMed, 967 papers related to telepathology and virtual microscopy have been retrieved, which involved 2904 Authors; corresponding authors were from 37 countries. Of those authors, 2213 co-authored just one paper. Papers were published on 344 different journals, of which only 52 from the Pathology field. An analysis of papers per year has been also attempted, that demonstrates variable research output in time. Conclusions From the proposed analysis, telepathology seems to have been consistently studied, in time, by about 400 researchers, with occasional participation of many other people. Telepathology research seems also to have varied in time, although some peaks in paper publishing are certainly related to the proceedings of the European congress on telepathology series, when they have been published on journals. However, some clear sign appears that suggests research in traditional telepathology, after a peak in 2000, showed some decline until virtual microscopy became mainstream, topic that currently pushes research again. The low number of clinical trials calls for more randomized studies in telepathology, to enable evidence-based application. PMID:21489197

  4. [Google Scholar and the h-index in biomedicine: the popularization of bibliometric assessment].

    PubMed

    Cabezas-Clavijo, A; Delgado-López-Cózar, E

    2013-01-01

    The aim of this study is to review the features, benefits and limitations of the new scientific evaluation products derived from Google Scholar, such as Google Scholar Metrics and Google Scholar Citations, as well as the h-index, which is the standard bibliometric indicator adopted by these services. The study also outlines the potential of this new database as a source for studies in Biomedicine, and compares the h-index obtained by the most relevant journals and researchers in the field of intensive care medicine, based on data extracted from the Web of Science, Scopus and Google Scholar. Results show that although the average h-index values in Google Scholar are almost 30% higher than those obtained in Web of Science, and about 15% higher than those collected by Scopus, there are no substantial changes in the rankings generated from one data source or the other. Despite some technical problems, it is concluded that Google Scholar is a valid tool for researchers in Health Sciences, both for purposes of information retrieval and for the computation of bibliometric indicators. PMID:23517697

  5. A critical review of the development, current hotspots, and future directions of Lake Taihu research from the bibliometrics perspective.

    PubMed

    Zhang, Yunlin; Yao, Xiaolong; Qin, Boqiang

    2016-07-01

    Lake Taihu, as the important drinking water source of the Yangtze River Delta urban agglomeration and the third largest freshwater lake in China, has experienced serious lake eutrophication and water quality deterioration in the past three decades. Growing scientific, political, and public attention has been given to the water quality of Lake Taihu. This study aimed to conduct a comparative quantitative and qualitative analysis of the development, current hotspots, and future directions of Lake Taihu research using a bibliometric analysis of eight well-studied lakes (Lake Taihu, Lake Baikal, Lake Biwa, Lake Erie, Lake Michigan, Lake Ontario, Lake Superior and Lake Victoria) around the world based on the Science Citation Index (SCI) database. A total of 1582 papers discussing Lake Taihu research were published in 322 journals in the past three decades. However, the first paper about Lake Taihu research was not found in the SCI database until 1989, and there were only zero, one, or two papers each year from 1989 to 1995. There had been rapid development in Lake Taihu research since 1996 and a sharp increase in papers since 2005. A keyword analysis showed that "sediment," "eutrophication", "Microcystis aeruginosa", "cyanobacterial blooms", and "remote sensing" were the most frequently used keywords of the study subject. Owing to its significant impact on aquatic ecosystems, a crucial emphasis has been placed on climate change recently. In addition, the future focuses of research directions, including (1) environmental effects of physical processes; (2) nutrient cycles and control and ecosystem responses; (3) cyanobacteria bloom monitoring, causes, forecast and management; (4) eutrophication and climate change interactions; and (5) ecosystem degradation mechanism and ecological practice of lake restoration, are presented based on the keyword analysis. Through multidisciplinary fields (physics, chemistry, and biology) cross and synthesis study of Lake Taihu, the

  6. Quantitative thermophoretic study of disease-related protein aggregates

    PubMed Central

    Wolff , Manuel; Mittag, Judith J.; Herling, Therese W.; Genst, Erwin De; Dobson, Christopher M.; Knowles, Tuomas P. J.; Braun, Dieter; Buell, Alexander K.

    2016-01-01

    Amyloid fibrils are a hallmark of a range of neurodegenerative disorders, including Alzheimer’s and Parkinson’s diseases. A detailed understanding of the physico-chemical properties of the different aggregated forms of proteins, and of their interactions with other compounds of diagnostic or therapeutic interest, is crucial for devising effective strategies against such diseases. Protein aggregates are situated at the boundary between soluble and insoluble structures, and are challenging to study because classical biophysical techniques, such as scattering, spectroscopic and calorimetric methods, are not well adapted for their study. Here we present a detailed characterization of the thermophoretic behavior of different forms of the protein α-synuclein, whose aggregation is associated with Parkinson’s disease. Thermophoresis is the directed net diffusional flux of molecules and colloidal particles in a temperature gradient. Because of their low volume requirements and rapidity, analytical methods based on this effect have considerable potential for high throughput screening for drug discovery. In this paper we rationalize and describe in quantitative terms the thermophoretic behavior of monomeric, oligomeric and fibrillar forms of α-synuclein. Furthermore, we demonstrate that microscale thermophoresis (MST) is a valuable method for screening for ligands and binding partners of even such highly challenging samples as supramolecular protein aggregates. PMID:26984748

  7. Quantitative study of prostate cancer using three dimensional fiber tractography

    PubMed Central

    Hedgire, Sandeep; Tonyushkin, Alexey; Kilcoyne, Aoife; Efstathiou, Jason A; Hahn, Peter F; Harisinghani, Mukesh

    2016-01-01

    AIM: To investigate feasibility of a quantitative study of prostate cancer using three dimensional (3D) fiber tractography. METHODS: In this institutional review board approved retrospective study, 24 men with biopsy proven prostate cancer underwent prostate magnetic resonance imaging (MRI) with an endorectal coil on a 1.5 T MRI scanner. Single shot echo-planar diffusion weighted images were acquired with b = 0.600 s/mm2, six gradient directions. Open-source available software TrackVis and its Diffusion Toolkit were used to generate diffusion tensor imaging (DTI) map and 3D fiber tracts. Multiple 3D spherical regions of interest were drawn over the areas of tumor and healthy prostatic parenchyma to measure tract density, apparent diffusion coefficient (ADC) and fractional anisotropy (FA), which were statistically analyzed. RESULTS: DTI tractography showed rich fiber tract anatomy with tract heterogeneity. Mean tumor region and normal parenchymal tract densities were 2.53 and 3.37 respectively (P < 0.001). In the tumor, mean ADC was 0.0011 × 10-3 mm2/s vs 0.0014 × 10-3 mm2/s in the normal parenchyma (P < 0.001). The FA values for tumor and normal parenchyma were 0.2047 and 0.2259 respectively (P = 0.3819). CONCLUSION: DTI tractography of the prostate is feasible and depicts congregate fibers within the gland. Tract density may offer new biomarker to distinguish tumor from normal tissue. PMID:27158426

  8. Semiautomatic Software For Quantitative Analysis Of Cardiac Positron Tomography Studies

    NASA Astrophysics Data System (ADS)

    Ratib, Osman; Bidaut, Luc; Nienaber, Christoph; Krivokapich, Janine; Schelbert, Heinrich R.; Phelps, Michael E.

    1988-06-01

    In order to derive accurate values for true tissue radiotracers concentrations from gated positron emission tomography (PET) images of the heart, which are critical for quantifying noninvasively regional myocardial blood flow and metabolism, appropriate corrections for partial volume effect (PVE) and contamination from adjacent anatomical structures are required. We therefore developed an integrated software package for quantitative analysis of tomographic images which provides for such corrections. A semiautomatic edge detection technique outlines and partitions the myocardium into sectors. Myocardial wall thickness is measured on the images perpendicularly to the detected edges and used to correct for PVE. The programs automatically correct for radioactive decay, activity calibration and cross contaminations for both static and dynamic studies. Parameters derived with these programs include tracer concentrations and their changes over time. They are used for calculating regional metabolic rates and can be further displayed as color coded parametric images. The approach was validated for PET imaging in 11 dog experiments. 2D echocardiograms (Echo) were recorded simultaneously to validate the edge detection and wall thickness measurement techniques. After correction for PVE using automatic WT measurement, regional tissue tracer concentrations derived from PET images correlated well with true tissue concentrations as determined by well counting (r=0.98). These preliminary studies indicate that the developed automatic image analysis technique allows accurate and convenient evaluation of cardiac PET images for the measurement of both, regional tracer tissue concentrations as well as regional myocardial function.

  9. Vulnerabilities—bibliometric analysis and literature review of evolving concepts

    NASA Astrophysics Data System (ADS)

    Giupponi, Carlo; Biscaro, Claudio

    2015-12-01

    In this work we analyse the evolution of the vulnerability concept in the research streams of climate change adaptation (CCA) and disaster risk reduction (DRR). We combine a traditional literature review with data mining procedures applied to bibliographic databases to reconstruct the history of the concept within various research topics, showing its evolution and convergences over time. To do that, we integrate different methods combining machine learning algorithms with network and cluster analyses to examine a set of 3757 articles, analysing their distinctive features and similarities on the basis of their contents as well as co-authorships. Bibliometric analyses enable the identification of different communities of articles, pinpointing key papers and authors, while literature review makes it possible to assess the concept of vulnerability evolved within and beyond research communities and scientific networks. Moreover, this work examines the role played by documents published by UN institutions (UNDRO, UNISDR, IPCC) in contributing to the evolution of vulnerability and related concepts. Results show that signs of convergence are evident between the two research streams, and that the IPCC reports have played a major role in proposing solutions for unifying definitions of vulnerability. We observe that the phases of preparation of the IPCC reports are very rich in methodological and terminological developments, while after publication, the literature shows evident signs of propagation of the proposed concepts. The DRR research stream developed before the research stream on CCA, but the latter flourished rapidly and became much larger in terms of number of publications. Nevertheless, in terms of contents, adaptation studies and the IPCC have shown increasing adoption of the concepts developed within the disaster research stream, in particular with regard to the interpretation of vulnerability as one of the dimensions of risk.

  10. [Bibliometrics and web use: the birth of altmetrics].

    PubMed

    Scotti, Valeria

    2015-04-01

    Counting citations that a research article received by other articles was the traditional bibliometric method for the evaluation of a scientific research. Citations have been used both to evaluate a scientific paper - usually in conjunction with the peer review methods - and to determine the quality of a scientific research output. The development of tools even more Web 2.0 oriented has profoundly changed the scientific communication process. In this context, many web tools have emerged including the so-called "social media" (e-i., Facebook, Twitter). Hence the need for new indicators to measure the influence of these tools on the scientific community and the emergence of alternative metrics. Altmetrics combines the traditional bibliometrics tool with the use of the web. Formulated with the purpose to measure new aspects of scientific production, these new metrics are placed in order to complement and supplement the existing indicators rather than act as their replacements. PMID:25959890

  11. Bibliometric profile of neurogenic bladder in the literature: a 20-year bibliometric analysis

    PubMed Central

    Gao, Yuan; Qu, Bo; Shen, Yan; Su, Xiao-jing; Dong, Xiao-yan; Chen, Xue-mei; Zhou, Yu-hong; Pi, Hong-ying

    2015-01-01

    Neurogenic bladder is a dysfunction of the lower urinary tract caused by nervous system disorder. We investigated the trends in publication of articles under the topic “neurogenic bladder” using bibliometric analysis. Articles on neurogenic bladder, published between 1995 and 2014, were retrieved from the ISI Web of Science citation database. We analyzed the search results for authors, countries, institutions, journals, and top-cited papers. A total of 1,904 articles were retrieved. There was a small increase in the number of articles on neurogenic bladder from 1995 (n = 43) to 2014 (n = 117). The USA was the leading country in the total number of articles (n = 598). However, the number of publications from China has rapidly increased, and China was ranked second in 2014. Emmanuel Chartier-Kastler (n = 65) was the most productive author, and University of Paris VI (Paris 6) (n = 61) was the most productive institution. The Journal of Urology published the greatest number of articles on this topic (n = 285). Articles on neurogenic bladder were often published in a professional journal under the category Urology & Nephrology, Neurosciences & Neurology, or Rehabilitation. Visualization analysis based on co-citation networks was conducted using CiteSpace III. Visualization analysis revealed that the hot spots in neurogenic bladder were botulinum toxin-A, prazosin, bethanechol, and afferent pathways. These findings provide new insight into the publication trends and hot spots in neurogenic bladder. PMID:26109957

  12. Exploring the Relationship between the Engineering and Physical Sciences and the Health and Life Sciences by Advanced Bibliometric Methods

    PubMed Central

    Waltman, Ludo; van Raan, Anthony F. J.; Smart, Sue

    2014-01-01

    We investigate the extent to which advances in the health and life sciences (HLS) are dependent on research in the engineering and physical sciences (EPS), particularly physics, chemistry, mathematics, and engineering. The analysis combines two different bibliometric approaches. The first approach to analyze the ‘EPS-HLS interface’ is based on term map visualizations of HLS research fields. We consider 16 clinical fields and five life science fields. On the basis of expert judgment, EPS research in these fields is studied by identifying EPS-related terms in the term maps. In the second approach, a large-scale citation-based network analysis is applied to publications from all fields of science. We work with about 22,000 clusters of publications, each representing a topic in the scientific literature. Citation relations are used to identify topics at the EPS-HLS interface. The two approaches complement each other. The advantages of working with textual data compensate for the limitations of working with citation relations and the other way around. An important advantage of working with textual data is in the in-depth qualitative insights it provides. Working with citation relations, on the other hand, yields many relevant quantitative statistics. We find that EPS research contributes to HLS developments mainly in the following five ways: new materials and their properties; chemical methods for analysis and molecular synthesis; imaging of parts of the body as well as of biomaterial surfaces; medical engineering mainly related to imaging, radiation therapy, signal processing technology, and other medical instrumentation; mathematical and statistical methods for data analysis. In our analysis, about 10% of all EPS and HLS publications are classified as being at the EPS-HLS interface. This percentage has remained more or less constant during the past decade. PMID:25360616

  13. Experimental bath engineering for quantitative studies of quantum control

    NASA Astrophysics Data System (ADS)

    Soare, A.; Ball, H.; Hayes, D.; Zhen, X.; Jarratt, M. C.; Sastrawan, J.; Uys, H.; Biercuk, M. J.

    2014-04-01

    We develop and demonstrate a technique to engineer universal unitary baths in quantum systems. Using the correspondence between unitary decoherence due to ambient environmental noise and errors in a control system for quantum bits, we show how a wide variety of relevant classical error models may be realized through in-phase or in-quadrature modulation on a vector signal generator producing a resonant carrier signal. We demonstrate our approach through high-bandwidth modulation of the 12.6-GHz carrier appropriate for trapped Yb171+ ions. Experiments demonstrate the reduction of coherent lifetime in the system in the presence of both engineered dephasing noise during free evolution and engineered amplitude noise during driven operations. In both cases, the observed reduction of coherent lifetimes matches well with quantitative models described herein. These techniques form the basis of a toolkit for quantitative tests of quantum control protocols, helping experimentalists characterize the performance of their quantum coherent systems.

  14. A bibliometric analysis of bipolar affective disorders using density-equalizing mapping and output benchmarking

    PubMed Central

    Vogelzang, B. H.; Scutaru, C.; Mache, S.; Vitzthum, K.; Kusma, B.; Schulte-Herbrüggen, O; Groneberg, D. A.; Quarcoo, D.

    2012-01-01

    Background: Bipolar affective disorder (BaD) has a great impact on health systems worldwide. Although bibliometric studies have been done on this subject, these studies did not do an analysis of the contents of papers, the cooperation between countries, or of the names currently used to describe the condition. Furthermore, the number of publications since the last bibliometric study has doubled. Aim: This study was to examine the recent developments in the field, explore main topics/subject areas of the top 10 authors in this research field, and to compare diagnosis-defined data between International Classification of Diseases, 10th edition (ICD-10) and Diagnostic and Statistical Manual of Mental Disorders, fourth edition (DSM-IV). Materials and Methods: Using distinct search terms, the Web of Science database developed by the Thompson Reuters Institute of Scientific Information was scanned for relevant items published between 1900 and 2008. Results were analyzed using scientometric methods and density-equalizing calculations. Results: We found an important increase of publications on the subject over the last decade. Most published studies came from North America and Europe, while the countries cooperating with each other were comparable to other areas of medical research. Although there has been an increase in publications on BaD (m=3.3 publications per year in the last decade), the number of works using the term bipolar disorder (BD) was considerably higher (m=141.8 publications per year in the last decade). We found that the subject areas, genetics and pharmacology were focuses of research for the 10 most prolific authors, all of whom where psychiatrists. Conclusion: Research interest in BaD is rising. Reflecting the two main disease classification systems, DSM and ICD, both terms BD and BaD are used in research, with a preponderance of the former. The research of the most prolific authors engages genetic and pharmacological questions. PMID:23372233

  15. A Bibliometric Analysis of PubMed Literature on Middle East Respiratory Syndrome

    PubMed Central

    Wang, Zhengting; Chen, Yongdi; Cai, Gaofeng; Jiang, Zhenggang; Liu, Kui; Chen, Bin; Jiang, Jianmin; Gu, Hua

    2016-01-01

    Middle East Respiratory Syndrome (MERS), a pandemic threat to human beings, has aroused huge concern worldwide, but no bibliometric studies have been conducted on MERS research. The aim of this study was to map research productivity on the disease based on the articles indexed in PubMed. The articles related to MERS dated from 2012 to 2015 were retrieved from PubMed. The articles were classified into three categories according to their focus. Publication outputs were assessed and frequently used terms were mapped using the VOS viewer software. A total of 443 articles were included for analysis. They were published in 162 journals, with Journal of Virology being the most productive (44 articles; 9.9%) and by six types of organizations, with universities being the most productive (276 articles; 62.4%).The largest proportion of the articles focused on basic medical sciences and clinical studies (47.2%) and those on prevention and control ranked third (26.2%), with those on other focuses coming in between (26.6%). The articles on prevention and control had the highest mean rank for impact factor (IF) (226.34), followed by those on basic medical sciences and clinical studies (180.23) and those on other focuses (168.03). The mean rank differences were statistically significant (p = 0.000). Besides, “conronavirus”, “case”, “transmission” and “detection” were found to be the most frequently used terms. The findings of this first bibliometric study on MERS suggest that the prevention and control of the disease has become a big concern and related research should be strengthened. PMID:27304963

  16. A Bibliometric Analysis of PubMed Literature on Middle East Respiratory Syndrome.

    PubMed

    Wang, Zhengting; Chen, Yongdi; Cai, Gaofeng; Jiang, Zhenggang; Liu, Kui; Chen, Bin; Jiang, Jianmin; Gu, Hua

    2016-01-01

    Middle East Respiratory Syndrome (MERS), a pandemic threat to human beings, has aroused huge concern worldwide, but no bibliometric studies have been conducted on MERS research. The aim of this study was to map research productivity on the disease based on the articles indexed in PubMed. The articles related to MERS dated from 2012 to 2015 were retrieved from PubMed. The articles were classified into three categories according to their focus. Publication outputs were assessed and frequently used terms were mapped using the VOS viewer software. A total of 443 articles were included for analysis. They were published in 162 journals, with Journal of Virology being the most productive (44 articles; 9.9%) and by six types of organizations, with universities being the most productive (276 articles; 62.4%).The largest proportion of the articles focused on basic medical sciences and clinical studies (47.2%) and those on prevention and control ranked third (26.2%), with those on other focuses coming in between (26.6%). The articles on prevention and control had the highest mean rank for impact factor (IF) (226.34), followed by those on basic medical sciences and clinical studies (180.23) and those on other focuses (168.03). The mean rank differences were statistically significant (p = 0.000). Besides, "conronavirus", "case", "transmission" and "detection" were found to be the most frequently used terms. The findings of this first bibliometric study on MERS suggest that the prevention and control of the disease has become a big concern and related research should be strengthened. PMID:27304963

  17. Quantitative studies on acetylcholinesterase in seven species of digenetic trematodes.

    PubMed

    Nizami, W A; Siddiqi, A H; Islam, M W

    1977-07-29

    Quantitative estimation of absolute levels and in vitro release of acetylcholinesterase (AChE) in seven species of digenetic trematodes: Isoparorchis hypselobagri from the swim bladder of catfish, Wallago attu; Srivastavaia indica and Gastrothylax crumenifer from the rumen, and Gigantocotyle explanatum from the liver of the water buffalo, Bubalus bubalis; Fasciolopsis buski, Echinostoma malayanum from the small intestine and Gastrodiscoides hominis from the caecum of the pig, Sus scrofa revealed that the enzyme is present in remarkably high quantities in species which inhibit gastrointestinal tract compared with those that parasitize liver and swim bladder. The rate of in vitro release of AChE also varies with the species which supports the view that such differential secretion probably takes place in situ as well to counteract peristalsis and it is a biochemical adaptation on the part of these trematodes. PMID:562036

  18. A quantitative histochemical study of the microvasculature of irradiated skin

    SciTech Connect

    Schwint, A.E.; Itoiz, M.E.; Cabrini, R.L. )

    1990-01-01

    Short-term X-ray damage to the microvasculature of the skin of newborn rats has been quantitated using Horseradish Peroxidase as a tracer. Image analysis of thick sections on which peroxidase was demonstrated histochemically revealed a radioinduced increase in vascular volume coupled with a decrease in vascular length and an altered frequency distribution of blood vessel calibers which resulted in early telangiectasia. The results afforded by direct counting of peroxidase positive macrophagic cells and microphotometric evaluation of peroxidase present in the connective tissue indicate a progressive increase in capillary permeability as a function of dose and time post-irradiation. The accuracy with which the affected region of blood vessels coincided with the area exposed to the beam favours the hypothesis of direct damage to the vessel wall as a major cause of radioinduced lesion.

  19. A Kernel-based Account of Bibliometric Measures

    NASA Astrophysics Data System (ADS)

    Ito, Takahiko; Shimbo, Masashi; Kudo, Taku; Matsumoto, Yuji

    The application of kernel methods to citation analysis is explored. We show that a family of kernels on graphs provides a unified perspective on the three bibliometric measures that have been discussed independently: relatedness between documents, global importance of individual documents, and importance of documents relative to one or more (root) documents (relative importance). The framework provided by the kernels establishes relative importance as an intermediate between relatedness and global importance, in which the degree of `relativity,' or the bias between relatedness and importance, is naturally controlled by a parameter characterizing individual kernels in the family.

  20. Content and bibliometric analyses of the Journal of Manual & Manipulative Therapy

    PubMed Central

    Simon, Corey B; Coronado, Rogelio A; Wurtzel, Wendy A; Riddle, Daniel L; George, Steven Z

    2014-01-01

    Background: Article characteristics and trends have been elucidated for other physical therapy-focused journals using content and bibliometric analysis. These findings are important for assessing the current state of a journal and for guiding future publication of research. To date, these analyses have not been performed for the Journal of Manual & Manipulative Therapy (JMMT). Objective: To describe content and trends for articles published in JMMT over a 20-year period (1993–2012). Methods: Journal articles were coded using previously-established domains (article type, participant type, research design, study purpose, and clinical condition). Total publications and proportion of publications based on domain were described. Articles specific to manual therapy intervention were examined and compared to data from other physical therapy-focused journals. Impact by citation and author was examined using bibliometric software. Results: Journal of Manual & Manipulative Therapy was found to have a recent acceleration in the number of articles published annually. Over time, topical reviews have decreased in favor of research reports. However, rigorous study designs have represented only a small portion of total journal content, and case reports have maintained a consistent publication presence. Manual therapy intervention articles in JMMT are predominantly case designs, however are similar in characteristics to manual therapy intervention articles published in other physical therapy-focused journals. For JMMT articles overall and manual therapy intervention articles across journals, young to middle-aged symptomatic adults with low back and/or neck pain were the most common study participants. Discussion: Increases in the number of papers and a move toward research reports were observed in JMMT over the 20-year period. Considerations for the future were outlined, including the publication of articles with more rigorous research designs. Manual therapy research for

  1. Assessing urology and nephrology research activity in Arab countries using ISI web of science bibliometric database

    PubMed Central

    2014-01-01

    Background Bibliometric analysis is increasingly being used for research assessment. The main objective of this study was to assess research output in Urology and Nephrology subject from the Arab countries. Original scientific articles or reviews published from the 21 Arab countries in “Urology and Nephrology” subject were screened using the ISI Web of Science database. Research productivity was evaluated based on a methodology developed and used in other bibliometric studies by analyzing the annual productivity, names of journals, citations; top 10 active institution and authors as well as country contribution to Urology and Nephrology research. Results Three thousand and seventy six documents in “urology and nephrology” subject category were retrieved from 104 journals. This represents 1.4% of the global research output in “urology and nephrology”. Four hundred and two documents (12.66%) were published in Annales D Urologie Journal. The h-index of the retrieved documents was 57. The total number of citations, at the time of data analysis, was 30401 with an average citation of 9.57 per document. Egypt, with a total publication of 1284 (40.43%) ranked first among the Arab countries in “urology and nephrology” subject category. Mansoura University in Egypt was the most productive institution with a total of 561 (15.33%) documents. Arab researchers collaborated most with researchers from the United States of America (226; 7.12%) in urology and nephrology research. Conclusion The present data reveals a good contribution of some Arab countries to the field of “urology and nephrology”. More efforts are needed by some other Arab countries to bridge the gap in urology and nephrology research. Overall, the quality of urology/nephrology research is considered relatively high as measured by h-index. Cooperation in urology/nephrology research should be encouraged in the Arab world to bridge the gap with that from developed countries. PMID:24758477

  2. Public health research in India in the new millennium: a bibliometric analysis

    PubMed Central

    Kalita, Anuska; Shinde, Sachin; Patel, Vikram

    2015-01-01

    Background Public health research has gained increasing importance in India's national health policy as the country seeks to address the high burden of disease and its inequitable distribution, and embarks on an ambitious agenda towards universalising health care. Objective This study aimed at describing the public health research output in India, its focus and distribution, and the actors involved in the research system. It makes recommendations for systematically promoting and strengthening public health research in the country. Design The study was a bibliometric analysis of PubMed and IndMed databases for years 2000–2010. The bibliometric data were analysed in terms of biomedical focus based on the Global Burden of Disease, location of research, research institutions, and funding agencies. Results A total of 7,893 eligible articles were identified over the 11-year search period. The annual research output increased by 42% between 2000 and 2010. In total, 60.8% of the articles were related to communicable diseases, newborn, maternal, and nutritional causes, comparing favourably with the burden of these causes (39.1%). While the burdens from non-communicable diseases and injuries were 50.2 and 10.7%, respectively, only 31.9 and 7.5% of articles reported research for these conditions. The north-eastern states and the Empowered-Action-Group states of India were the most under-represented for location of research. In total, 67.2% of papers involved international collaborations and 49.2% of these collaborations were with institutions in the UK or USA; 35.4% of the publications involved international funding and 71.2% of funders were located in the UK or USA. Conclusions While public health research output in India has increased significantly, there are marked inequities in relation to the burden of disease and the geographic distribution of research. Systematic priority setting, adequate funding, and institutional capacity building are needed to address these

  3. Critical review of a quantitative study of a specialty in high energy particle physics

    SciTech Connect

    White, D H; Sullivan, D

    1980-01-01

    A review is made of the authors' series of quantitative, historical, and social studies of the weak interactions of elementary particles. A short intellectual history, the quantitative methodology, and a summary of the papers analyzing specific episodes in this field are presented. The social organization of the field is described, and an overall policy for resource management is discussed. 6 figures, 3 tables.

  4. Use of Quantitative Microbial Risk Assessment to Improve Interpretation of a Recreational Water Epidemiological Study

    EPA Science Inventory

    We conducted a supplemental water quality monitoring study and quantitative microbial risk assessment (QMRA) to complement the United States Environmental Protection Agency’s (U.S. EPA) National Epidemiological and Environmental Assessment of Recreational Water study at Boq...

  5. Post-deposition bioink self-assembly: a quantitative study.

    PubMed

    Shafiee, Ashkan; McCune, Matthew; Forgacs, Gabor; Kosztin, Ioan

    2015-12-01

    The outcome of a bioprinting process depends on both the deposition of the discrete bioink units and their ability to self-assemble into the desired structure following deposition. Post-printing structure formation is an autonomous process governed by fundamental biological organizing principles. As the quantitative formulation of such principles is notoriously difficult, bioprinting remains largely a trial and error approach. To address this problem, specifically in extrusion bioprinting, we have recently developed an effective computational method, the cellular particle dynamics (CPDs). We have demonstrated the predictive power of CPD in cases of simple printed constructs prepared with spherical multicellular bioink units. Here we generalize CPD to the important practical case of tubular grafts printed with cylindrical bioink units by taking into account the realistic experimental situation in which the length and the volume of the cylinders decrease post-printing. Based on our results, we provide a set of instructions for the use of CPD simulations to directly predict tubular graft formation without the need to carry out the corresponding complex and expensive control experiments. Using these instructions allows the efficient and timely biofabrication of tubular organ structures. A particularly instructive outcome of our analysis is that building tubular organ structures, such as vascular grafts by bioprinting can be done considerably faster by using cylindrical rather than spherical bionk units. PMID:26538193

  6. Young people, alcohol, and designer drinks: quantitative and qualitative study.

    PubMed Central

    Hughes, K.; MacKintosh, A. M.; Hastings, G.; Wheeler, C.; Watson, J.; Inglis, J.

    1997-01-01

    OBJECTIVE: To examine the appeal of "designer drinks" to young people. DESIGN: Qualitative and quantitative research comprising group discussions and questionnaire led interviews with young people accompanied by a self completion questionnaire. SETTINGS: Argyll and Clyde Health Board area, west Scotland. SUBJECTS: Eight groups aged 12-17 years; 824 aged 12-17 recruited by multistage cluster probability sample from the community health index. RESULTS: Young people were familiar with designer drinks, especially MD 20/20 and leading brands of strong white cider. Attitudes towards these drinks varied quite distinctly with age, clearly reflecting their attitudes towards and motivations for drinking in general. The brand imagery of designer drinks-in contrast with that of more mainstream drinks-matched many 14 and 15 year olds' perceptions and expectations of drinking. Popularity of designer drinks peaked between the ages of 13 and 16 while more conventional drinks showed a consistent increase in popularity with age. Consumption of designer drinks tended to be in less controlled circumstances and was associated with heavier alcohol intake and greater drunkenness. CONCLUSIONS: Designer drinks are a cause for concern. They appeal to young people, often more so than conventional drinks, and are particularly attractive to 14-16 year olds. Consumption of designer drinks is also associated with drinking in less controlled environments, heavier drinking, and greater drunkenness. There is a need for policy debate to assess the desirability of these drinks and the extent to which further controls on their marketing are required. PMID:9040387

  7. Substance use disorders in Arab countries: research activity and bibliometric analysis

    PubMed Central

    2014-01-01

    Background Substance use disorders, which include substance abuse and substance dependence, are present in all regions of the world including Middle Eastern Arab countries. Bibliometric analysis is an increasingly used tool for research assessment. The main objective of this study was to assess research productivity in the field of substance use disorders in Arab countries using bibliometric indicators. Methodology Original or review research articles authored or co-authored by investigators from Arab countries about substance use disorders during the period 1900 – 2013 were retrieved using the ISI Web of Science database. Research activity was assessed by analyzing the annual research productivity, contribution of each Arab country, names of journals, citations, and types of abused substances. Results Four hundred and thirteen documents in substance use disorders were retrieved. Annual research productivity was low but showed a significant increase in the last few years. In terms of quantity, Kingdom of Saudi Arabia (83 documents) ranked first in research about substance use disorders while Lebanon (17.4 documents per million) ranked first in terms of number of documents published per million inhabitants. Retrieved documents were found in different journal titles and categories, mostly in Drug and Alcohol Dependence Journal. Authors from USA appeared in 117 documents published by investigators from Arab countries. Citation analysis of retrieved documents showed that the average citation per document was 10.76 and the h - index was 35. The majority of retrieved documents were about tobacco and smoking (175 documents) field while alcohol consumption and abuse research was the least with 69 documents. Conclusion The results obtained suggest that research in this field was largely neglected in the past. However, recent research interest was observed. Research output on tobacco and smoking was relatively high compared to other substances of abuse like illicit drugs

  8. Type 2 Diabetes Research Yield, 1951-2012: Bibliometrics Analysis and Density-Equalizing Mapping

    PubMed Central

    Geaney, Fiona; Scutaru, Cristian; Kelly, Clare; Glynn, Ronan W.; Perry, Ivan J.

    2015-01-01

    The objective of this paper is to provide a detailed evaluation of type 2 diabetes mellitus research output from 1951-2012, using large-scale data analysis, bibliometric indicators and density-equalizing mapping. Data were retrieved from the Science Citation Index Expanded database, one of the seven curated databases within Web of Science. Using Boolean operators "OR", "AND" and "NOT", a search strategy was developed to estimate the total number of published items. Only studies with an English abstract were eligible. Type 1 diabetes and gestational diabetes items were excluded. Specific software developed for the database analysed the data. Information including titles, authors’ affiliations and publication years were extracted from all files and exported to excel. Density-equalizing mapping was conducted as described by Groenberg-Kloft et al, 2008. A total of 24,783 items were published and cited 476,002 times. The greatest number of outputs were published in 2010 (n=2,139). The United States contributed 28.8% to the overall output, followed by the United Kingdom (8.2%) and Japan (7.7%). Bilateral cooperation was most common between the United States and United Kingdom (n=237). Harvard University produced 2% of all publications, followed by the University of California (1.1%). The leading journals were Diabetes, Diabetologia and Diabetes Care and they contributed 9.3%, 7.3% and 4.0% of the research yield, respectively. In conclusion, the volume of research is rising in parallel with the increasing global burden of disease due to type 2 diabetes mellitus. Bibliometrics analysis provides useful information to scientists and funding agencies involved in the development and implementation of research strategies to address global health issues. PMID:26208117

  9. Type 2 Diabetes Research Yield, 1951-2012: Bibliometrics Analysis and Density-Equalizing Mapping.

    PubMed

    Geaney, Fiona; Scutaru, Cristian; Kelly, Clare; Glynn, Ronan W; Perry, Ivan J

    2015-01-01

    The objective of this paper is to provide a detailed evaluation of type 2 diabetes mellitus research output from 1951-2012, using large-scale data analysis, bibliometric indicators and density-equalizing mapping. Data were retrieved from the Science Citation Index Expanded database, one of the seven curated databases within Web of Science. Using Boolean operators "OR", "AND" and "NOT", a search strategy was developed to estimate the total number of published items. Only studies with an English abstract were eligible. Type 1 diabetes and gestational diabetes items were excluded. Specific software developed for the database analysed the data. Information including titles, authors' affiliations and publication years were extracted from all files and exported to excel. Density-equalizing mapping was conducted as described by Groenberg-Kloft et al, 2008. A total of 24,783 items were published and cited 476,002 times. The greatest number of outputs were published in 2010 (n=2,139). The United States contributed 28.8% to the overall output, followed by the United Kingdom (8.2%) and Japan (7.7%). Bilateral cooperation was most common between the United States and United Kingdom (n=237). Harvard University produced 2% of all publications, followed by the University of California (1.1%). The leading journals were Diabetes, Diabetologia and Diabetes Care and they contributed 9.3%, 7.3% and 4.0% of the research yield, respectively. In conclusion, the volume of research is rising in parallel with the increasing global burden of disease due to type 2 diabetes mellitus. Bibliometrics analysis provides useful information to scientists and funding agencies involved in the development and implementation of research strategies to address global health issues. PMID:26208117

  10. Real-time quantitative phase imaging for cell studies

    NASA Astrophysics Data System (ADS)

    Pham, Hoa Vinh

    Most biological cells are not clearly visible with a bright field microscope. Several methods have been developed to improve contrast in cell imaging, including use of exogenous contrast agents such as fluorescence microscopy, as well as utilizing properties of light-specimen interaction for optics design, to reveal the endogenous contrast, such as phase contrast microscopy (PCM) and differential interference contrast (DIC) microscopy. Although PCM and DIC methods significantly improve the image contrast without the need for staining agents, they only provide qualitative information about the phase change induced by the cells as light passes through them. Quantitative phase imaging (QPI) has recently emerged as an effective imaging tool which provides not only better image contrast but also cell-induced phase shifts in the optical pathlength, thus allowing nanometer-scale measurements of structures and dynamics of the cells. Other important aspects of an imaging system are its imaging speed and throughput. High-throughput, high-speed, real-time quantitative phase imaging with high spatial and temporal sensitivity is highly desirable in many applications including applied physics and biomedicine. In this dissertation, to address this need, I discuss the development of such an imaging system that includes the white light diffraction phase microscopy (wDPM), a new optical imaging method, and image reconstruction/analysis algorithms using graphics processing units (GPUs). wDPM can measure optical pathlength changes at nanometer scale both spatially and temporally with single-shot image acquisition, enabling very fast imaging. I also exploit the broadband spectrum of white light used as the light source in wDPM to develop a system called spectroscopic diffraction phase microscopy (sDPM). This sDPM system allows QPI measurements at several wavelengths, which solves the problem of thickness and refractive index coupling in the phase shifts induced by the cell, and which

  11. Fullerene data mining using bibliometrics and database tomography

    PubMed

    Kostoff; Braun; Schubert; Toothman; Humenik

    2000-01-01

    Database tomography (DT) is a textual database analysis system consisting of two major components: (1) algorithms for extracting multiword phrase frequencies and phrase proximities (physical closeness of the multiword technical phrases) from any type of large textual database, to augment (2) interpretative capabilities of the expert human analyst. DT was used to derive technical intelligence from a fullerenes database derived from the Science Citation Index and the Engineering Compendex. Phrase frequency analysis by the technical domain experts provided the pervasive technical themes of the fullerenes database, and phrase proximity analysis provided the relationships among the pervasive technical themes. Bibliometric analysis of the fullerenes literature supplemented the DT results with author/journal/institution publication and citation data. Comparisons of fullerenes results with past analyses of similarly structured near-earth space, chemistry, hypersonic/supersonic flow, aircraft, and ship hydrodynamics databases are made. One important finding is that many of the normalized bibliometric distribution functions are extremely consistent across these diverse technical domains and could reasonably be expected to apply to broader chemical topics than fullerenes that span multiple structural classes. Finally, lessons learned about integrating the technical domain experts with the data mining tools are presented. PMID:10661546

  12. Erosion of Terrestrial Rift Flank Topography: A Quantitative Study

    NASA Technical Reports Server (NTRS)

    Weissel, Jeffrey K.

    1999-01-01

    Many rifted or passive continental margins feature a seaward-facing erosional escarpment which abruptly demarcates deeply weathered, low relief, interior uplands from a deeply incised, high relief coastal zone. It is generally accepted that these escarpments originate at the time of continental rifting and propagate inland through the elevated rift flank topography at rates on the order of 1 km/Myr over the course of a margin's history. Considering the length of passive margins worldwide and an average rift flank plateau height of several hundred meters, it is clear that sediment eroded from passive margins is an important component of the mass flux from continents to oceans through geologic time. The overall goal of the research reported here is to develop a quantitative understanding of the kinematics of escarpment propagation across passive margins and the underlying geological processes responsible for this behavior. Plateau-bounding escarpments in general exhibit two basic forms depending on the direction of surface water drainage on the plateau interior relative to the escarpment. Where surface water flows away from the escarpment, the escarpment takes the form of subdued embayments and promontories, such that its overall trend remains fairly straight as it evolves with time. Where upland streams flow across the escarpment, it takes the form of dramatic, narrow gorges whose heads appear to propagate up the plateau drainage systems as large-scale knickpoints. From work on the Colorado Plateau, Schmidt (1987) noted that the Colorado River is located much closer to the Grand Canyon's south rim, a drainage divide escarpment, than to the north rim, which is a gorge-like escarpment. The main implication is that the gorge-like form might be associated with higher long-term average erosion rates compared to the drainage divide escarpment type.

  13. Development of biomedical publications on ametropia research in PubMed from 1845 to 2010: a bibliometric analysis

    PubMed Central

    Xu, Chang-Tai; Li, Shan-Qu; Lü, Yong-Gang; Pan, Bo-Rong

    2011-01-01

    AIM We have carried out a bibliometric analysis on the development of ametropia literature to determine its growth rule and tendency, and to provide the basis for the problems related to ametropia research. METHODS Literatures that contained the descriptors of ametropia in title or paper published before Nov. 10, 2010 in PubMed databases (www.ncbi.nlm.nih.gov/Pubmed) were selected. As bibliometric indicators of ametropia, biomedical journals referring to ophthalmology by ISSN were calculated. The principal bibliometric indicators: Price's and Bradford's laws were applied on the increase or dispersion of scientific literature, the participation index of languages and the journals. By means of manual coding, literatures were classified according to documents study and statistical analysis. RESULTS The literatures cited in ametropia, astigmatism, myopia and hypermetropia had accumulated to 26475, which consists of Review (n=1560), Randomized Controlled Trial (n=776), Practice Guideline (n=10), Meta-Analysis (n=23), Letter (n=1222), Editorial (n=328), Clinical Trial (n=1726) and Others (n=20830), and Humans (n=23073), Animals(n=1434) and others (n=1968). 1136 literatures were included in PubMed Central, 22384 in MEDLINE and 2955 in others. The ametropia literatures rose every 5 years which of the ametropia-year cumulated amount of the literatures had three periods: before 1900, slowly increasing from 1901 to 1950, rapidly rising from 1951 to 2010 (increased approximate exponentiation exponent). Sixty kinds of languages listed in PubMed databases, of which English is dominant for aborting to ametropia research documents before 2010 (77.32%, 20471/26475). The document languages of top eight account for 95.58% (English, German, French, Japanese, Russian, Italian, Spanish, Chinese), and others for 4.42% (1171/26475). The SCI database includes 48 ophthalmologic journals and the impact factor of 39 journals is ≥1 on Thomson-Reuters in 2010. Of 48 ophthalmologic journals

  14. The emerging science of quantitative imaging biomarkers terminology and definitions for scientific studies and regulatory submissions.

    PubMed

    Kessler, Larry G; Barnhart, Huiman X; Buckler, Andrew J; Choudhury, Kingshuk Roy; Kondratovich, Marina V; Toledano, Alicia; Guimaraes, Alexander R; Filice, Ross; Zhang, Zheng; Sullivan, Daniel C

    2015-02-01

    The development and implementation of quantitative imaging biomarkers has been hampered by the inconsistent and often incorrect use of terminology related to these markers. Sponsored by the Radiological Society of North America, an interdisciplinary group of radiologists, statisticians, physicists, and other researchers worked to develop a comprehensive terminology to serve as a foundation for quantitative imaging biomarker claims. Where possible, this working group adapted existing definitions derived from national or international standards bodies rather than invent new definitions for these terms. This terminology also serves as a foundation for the design of studies that evaluate the technical performance of quantitative imaging biomarkers and for studies of algorithms that generate the quantitative imaging biomarkers from clinical scans. This paper provides examples of research studies and quantitative imaging biomarker claims that use terminology consistent with these definitions as well as examples of the rampant confusion in this emerging field. We provide recommendations for appropriate use of quantitative imaging biomarker terminological concepts. It is hoped that this document will assist researchers and regulatory reviewers who examine quantitative imaging biomarkers and will also inform regulatory guidance. More consistent and correct use of terminology could advance regulatory science, improve clinical research, and provide better care for patients who undergo imaging studies. PMID:24919826

  15. Study on global cloud computing research trend

    NASA Astrophysics Data System (ADS)

    Ma, Feicheng; Zhan, Nan

    2014-01-01

    Since "cloud computing" was put forward by Google , it quickly became the most popular concept in IT industry and widely permeated into various areas promoted by IBM, Microsoft and other IT industry giants. In this paper the methods of bibliometric analysis were used to investigate the global cloud computing research trend based on Web of Science (WoS) database and the Engineering Index (EI) Compendex database. In this study, the publication, countries, institutes, keywords of the papers was deeply studied in methods of quantitative analysis, figures and tables are used to describe the production and the development trends of cloud computing.

  16. Interactions among Online Learners: A Quantitative Interdisciplinary Study

    ERIC Educational Resources Information Center

    Jain, Pawan; Jain, Sachin; Jain, Smita

    2011-01-01

    This study concerns the design and development of online instruction and specifically targets interaction and communication between online learners. Facilitating appropriate and meaningful interactions in designing instruction is a major goal for anyone developing a course, especially an online class. The data for this study came from the online…

  17. Rating and Ranking the Role of Bibliometrics and Webometrics in Nursing and Midwifery

    PubMed Central

    Davidson, Patricia M.; Newton, Phillip J.; Ferguson, Caleb

    2014-01-01

    Background. Bibliometrics are an essential aspect of measuring academic and organizational performance. Aim. This review seeks to describe methods for measuring bibliometrics, identify the strengths and limitations of methodologies, outline strategies for interpretation, summarise evaluation of nursing and midwifery performance, identify implications for metric of evaluation, and specify the implications for nursing and midwifery and implications of social networking for bibliometrics and measures of individual performance. Method. A review of electronic databases CINAHL, Medline, and Scopus was undertaken using search terms such as bibliometrics, nursing, and midwifery. The reference lists of retrieved articles and Internet sources and social media platforms were also examined. Results. A number of well-established, formal ways of assessment have been identified, including h- and c-indices. Changes in publication practices and the use of the Internet have challenged traditional metrics of influence. Moreover, measuring impact beyond citation metrics is an increasing focus, with social media representing newer ways of establishing performance and impact. Conclusions. Even though a number of measures exist, no single bibliometric measure is perfect. Therefore, multiple approaches to evaluation are recommended. However, bibliometric approaches should not be the only measures upon which academic and scholarly performance are evaluated. PMID:24550691

  18. [Bibliometric indexes of the editions, publishing the articles on the problems of morphology, and some bibliometric parameters of the authors of morphological publications].

    PubMed

    Shevliuk, N N

    2013-01-01

    The article presents a comparative assessment of some bibliometric parameters of national journals, publishing the articles on the problems of morphological scientific disciplines, and concise analysis of the publication activity of morphologists. The data are given on the application of bibliometric indexes for the evaluation of the scientific contribution of national researchers to the field of morphology. The information contained in the national database-- Russian Index of Scientific Citation, and that collected by means of selected overview of the national and foreign medical and biological journals, publishing the articles on various problems of morphological sciences during the last 20 years, served as the basis for the analysis. It is noted that the authors should consider the bibliometric indexes of the journals to which they submit their articles. PMID:24592695

  19. Nuclear medicine and imaging research (quantitative studies in radiopharmaceutical science)

    SciTech Connect

    Cooper, M.; Beck, R.N.

    1992-06-01

    This report describes three studies aimed at using radiolabeled pharmaceuticals to explore brain function and anatomy. The first section describes the chemical preparation of (F18)fluorinated benzamides (dopamine D-2 receptor tracers), (F18)fluorinated benzazepines (dopamine D-1 receptor tracers), and tissue distribution of (F18)-fluoxetine (serotonin reuptake site tracer). The second section relates pharmacological and behavioral studies of amphetamines. The third section reports on progress made with processing of brain images from CT, MRI and PET/SPECT with regards to brain metabolism of glucose during mental tasks.

  20. Commercial Activities in Primary Schools: A Quantitative Study

    ERIC Educational Resources Information Center

    Raine, Gary

    2007-01-01

    The commercialisation of schools is a controversial issue, but very little is known about the actual situation in UK schools. The aim of this study was to investigate, with particular reference to health education and health promotion, commercial activities and their regulation in primary schools in the Yorkshire and Humber region of the UK. A…

  1. Service Learning, Phonemic Perception, and Learner Motivation: A Quantitative Study

    ERIC Educational Resources Information Center

    Medina, Almitra; Gordon, Leslie

    2014-01-01

    A nine-week empirical study of 25 adults in a second language (L2) Spanish phonetics course explored whether students' participation in service-learning language exchange sessions with native Spanish speakers outside of class influenced learners' (1) motivation for foreign language learning and (2) phonemic perception in Spanish. Divided…

  2. Quantitative modeling and analysis in environmental studies. Technical report

    SciTech Connect

    Gaver, D.P.

    1994-10-01

    This paper reviews some of the many mathematical modeling and statistical data analysis problems that arise in environmental studies. It makes no claim to be comprehensive nor truly up-to-date. It will appear as a chapter in a book on ecotoxicology to be published by CRC Press, probably in 1995. Workshops leading to the book creation were sponsored by The Conte Foundation.

  3. Quantitative studies of Savannah River aquatic insects, 1959--1985

    SciTech Connect

    Soltis, R.; Hart, D.; Nagy, T.

    1986-10-30

    As part of a long-term study of water quality patterns, scientists from the Academy of Natural Sciences have collected aquatic insects from artificial substrates placed at several stations in Savannah River. This report presents the first detailed compilation and analysis of this substantial data base, and examines patterns of variations of insect distribution and abundance (both spatial and temporal) during the last quarter century. Data on the number of individuals of various taxa found in the insect traps were obtained from tables in the Academy`s cursory reports. Computer data files created from these records were subjected to extensive statistical analyses in order to examine variation among stations, seasons and years in the abundances of major taxa and various aggregate properties of the insect assemblage. Although a total of 83 taxa were collected over the 27-year study, 10 taxa accounted for nearly 80% of the individuals collected from the traps, hence there 10 taxa were analyzed more intensively.

  4. Quantitative studies of Savannah River aquatic insects, 1959--1985

    SciTech Connect

    Soltis, R.; Hart, D.; Nagy, T.

    1986-10-30

    As part of a long-term study of water quality patterns, scientists from the Academy of Natural Sciences have collected aquatic insects from artificial substrates placed at several stations in Savannah River. This report presents the first detailed compilation and analysis of this substantial data base, and examines patterns of variations of insect distribution and abundance (both spatial and temporal) during the last quarter century. Data on the number of individuals of various taxa found in the insect traps were obtained from tables in the Academy's cursory reports. Computer data files created from these records were subjected to extensive statistical analyses in order to examine variation among stations, seasons and years in the abundances of major taxa and various aggregate properties of the insect assemblage. Although a total of 83 taxa were collected over the 27-year study, 10 taxa accounted for nearly 80% of the individuals collected from the traps, hence there 10 taxa were analyzed more intensively.

  5. [Experimental study of the heaptotoxic effect of toluol III. Quantitative morphological study].

    PubMed

    Aranka, H; Zsuzsa, B; Gábor, F; György, U

    1976-07-01

    Hepatotoxic effect of the analitically pure toluene used in the Chemical Factory "Tiszai" was investigated by the aid of quantitative morphological method on male rats of line CFY. Toluene was administered intraperitoneally and subcutaneously. It was established, that there exists a nearly lineal correlation between the logarithms of intraperitoneally administered doses of toluene, the number and area of mitochondria localized in the unite area of the hepatocyte, and between the increase of number of matrix-granules in the mitochondria. The average-area of the mitochondria remained unchanged. As an effect of large intraperitoneal doses of toluene increase of the density of nuclei and the nucleus-plasma proportion could be revealed. There exists a nearly lineal correlation between the logarithms of intraperitoneal and subcutaneous doses of toluene and the decrease of volume of the cell nuclei. Statistical curves of the nuclei-variation-study as an effect of large doses show two peaks. Authors stress the importance of quantitative morphological studies in the toxicology. Results of such investigations should be evaluated in connection with each other. PMID:940573

  6. A quantitative study of a physics-first pilot program

    SciTech Connect

    Pasero, Spencer Lee; /Northern Illinois U.

    2008-09-01

    Hundreds of high schools around the United States have inverted the traditional core sequence of high school science courses, putting physics first, followed by chemistry, and then biology. A quarter-century of theory, opinion, and anecdote are available, but the literature lacks empirical evidence of the effects of the program. The current study was designed to investigate the effects of the program on science achievement gain, growth in attitude toward science, and growth in understanding of the nature of scientific knowledge. One hundred eighty-five honor students participated in this quasi-experiment, self-selecting into either the traditional or inverted sequence. Students took the Explore test as freshmen, and the Plan test as sophomores. Gain scores were calculated for the composite scores and for the science and mathematics subscale scores. A two-factor analysis of variance (ANOVA) on course sequence and cohort showed significantly greater composite score gains by students taking the inverted sequence. Participants were administered surveys measuring attitude toward science and understanding of the nature of scientific knowledge twice per year. A multilevel growth model, compared across program groups, did not show any significant effect of the inverted sequence on either attitude or understanding of the nature of scientific knowledge. The sole significant parameter showed a decline in student attitude independent of course sequence toward science over the first two years of high school. The results of this study support the theory that moving physics to the front of the science sequence can improve achievement. The importance of the composite gain score on tests vertically aligned with the high-stakes ACT is discussed, and several ideas for extensions of the current study are offered.

  7. Quantitative study of long-term solar and climatic changes

    NASA Technical Reports Server (NTRS)

    Eddy, J. A.

    1982-01-01

    Long term variations in the diameter and the shape of the Sun were studied. Daily observations of the Sun's diameter made at the Greenwich Observatory between 1836 and 1953 were analysed and interpreted. The data was converted into digital form and then screened and processed. It was found that the horizontal diameter of the Sun measured at Greenwich appears to have decreased systematically between 1880 and 1953 at a rate of 1.2 plus or minus 0.6 minutes of arc per century.

  8. Quantitative studies of bird movement: a methodological review

    USGS Publications Warehouse

    Nichols, J.D.; Kaiser, A.

    1999-01-01

    The past several years have seen development of a number of statistical models and methods for drawing inferences about bird movement using data from marked individuals. It can be difficult to keep up with this rapid development of new methods, so our purpose here is to categorize and review methods for drawing inferences about avian movement. We also outline recommendations about future work dealing both with methods development and actual studies directed at hypotheses about bird movement of interest from conservation, management, or ecological perspectives.

  9. Conformational stability of dimeric proteins: quantitative studies by equilibrium denaturation.

    PubMed Central

    Neet, K. E.; Timm, D. E.

    1994-01-01

    The conformational stability of dimeric globular proteins can be measured by equilibrium denaturation studies in solvents such as guanidine hydrochloride or urea. Many dimeric proteins denature with a 2-state equilibrium transition, whereas others have stable intermediates in the process. For those proteins showing a single transition of native dimer to denatured monomer, the conformational stabilities, delta Gu (H2O), range from 10 to 27 kcal/mol, which is significantly greater than the conformational stability found for monomeric proteins. The relative contribution of quaternary interactions to the overall stability of the dimer can be estimated by comparing delta Gu (H2O) from equilibrium denaturation studies to the free energy associated with simple dissociation in the absence of denaturant. In many cases the large stabilization energy of dimers is primarily due to the intersubunit interactions and thus gives a rationale for the formation of oligomers. The magnitude of the conformational stability is related to the size of the polypeptide in the subunit and depends upon the type of structure in the subunit interface. The practical use, interpretation, and utility of estimation of conformational stability of dimers by equilibrium denaturation methods are discussed. PMID:7756976

  10. Rutile geochemistry and its potential use in quantitative provenance studies

    NASA Astrophysics Data System (ADS)

    Zack, T.; von Eynatten, H.; Kronz, A.

    2004-10-01

    Rutile is among the most stable detrital minerals in sedimentary systems. Information contained in rutile is therefore of prime importance, especially in the study of mature sediments, where most diagnostic minerals are no longer stable. In contrast to zircon, rutile provides information about the last metamorphic cycle as rutile is not stable at greenschist facies conditions. Several known geochemical characteristics of rutile can be used to retrace provenance. The lithology of source rocks can be determined using Nb and Cr contents in rutile, because the most important source rocks for rutile, metapelites and metabasites, imprint a distinct Nb and Cr signature in rutiles. Since Zr in rutile, coexisting with zircon and quartz, is extremely temperature dependent, this relationship can be used as a geothermometer. Metapelites always contain zircon and quartz, thus the Nb and Cr signatures of metapelites indicate rutiles that can be used for thermometry. The result is effectively a single-mineral geothermometer, which is to our knowledge the first of its kind in provenance studies. Several other trace elements are variably enriched in rutile, but the processes creating these variations are so far not understood. In a case study, Al, Si, V, Cr, Fe, Zr, Nb and W contents in rutiles were obtained by electron microprobe from three sediment samples from Upstate New York. A Pleistocene glacial sand, whose source was granulite-facies rocks of the southern Adirondacks, has detrital rutile geochemical signatures which are consistent with the local Geology; a predominantly metapelitic source with a minor metabasitic contribution. Calculated temperatures for the metapelitic rutiles from the glacial sand are consistent with a predominantly granulite-facies source. The two other samples are from Paleozoic clastic wedges deposited in the foreland of the Taconian and Acadian orogenies. Here several geochemical patterns of detrital rutiles are comparable to rutiles derived from the

  11. Introducing a feminist perspective to nursing curricula: a quantitative study.

    PubMed

    Boughn, S; Wang, H

    1994-03-01

    Feminist concerns of the nursing profession are examined and it is argued that feminism provides the ideology and impetus for social change. The purpose of this study is to investigate the effects on the attitudes and beliefs of nursing students who take a feminist-oriented women's health course. The course went beyond a scientific model of women's health and examined women's health issues as they are related to the concerns of women as consumers and providers. A questionnaire assessing the effects of the course was administered at the beginning and again at the end of the course. Results indicated that the course produced significant changes in the attitudes and beliefs of the experimental subjects in areas of professional activism; high regard for self, nurses, and women; and social activism against sexism in the media and violence against women. PMID:8046506

  12. Physics in Cuba from the Perspective of Bibliometrics

    NASA Astrophysics Data System (ADS)

    Marx, Werner; Cardona, Manuel

    We present a bibliometric analysis of the development of the physical sciences in Cuba since the revolution of 1959. We analyze, using available databases (Web of Science, Essential Science Indicators, INSPEC), the development of the output (number of publications of authors based in Cuba) and of their impact (number of citations) from 1959 until now. We discuss the productivity of Cuba in comparison to the Latin American sister republics and the collaborative efforts between Cuba and highly developed countries. The most important areas of scientific activity within the field of physics, the preferred journals and the leading affiliations are identified. The most frequently cited Cuban physics publications are given. Finally, the overall scientific ranking of Cuba among the world nations is investigated.

  13. Bibliometric Investigations at the Special Astrophysical Observatory RAS

    NASA Astrophysics Data System (ADS)

    Filippova, Ekaterina

    Bibliometric data for the Special Astrophysical Observatory are presented. Statistics and analysis of issues being brought out at SAO are given. Statistical data on publication of SAO research papers from the day of foundation of the observatory through 2000 are presented. The numbers of papers that appeared in domestic and foreign scientific issues are compared. An attempt is made to analyze the correlation of the number of scientific papers with the research of the observatory and also with the economical situation in Russia. It can be seen that the steady rise in publications observed from 1968 to 1991 gave way to an abrupt fall during the first (1991--1995) and second (1998) crises in our country.

  14. Quantitative study on the chemical solution deposition of zinc oxysulfide

    SciTech Connect

    Reinisch, Michael; Perkins, Craig L.; Steirer, K. Xerxes

    2015-11-21

    Zinc Oxysulfide (ZnOS) has demonstrated potential in the last decade to replace CdS as a buffer layer material since it is a wide-band-gap semiconductor with performance advantages over CdS (Eg = 2.4 eV) in the near UV-range for solar energy conversion. However, questions remain on the growth mechanisms of chemical bath deposited ZnOS. In this study, a detailed model is employed to calculate solubility diagrams that describe simple conditions for complex speciation control using only ammonium hydroxide without additional base. For these conditions, ZnOS is deposited via aqueous solution deposition on a quartz crystal microbalance in a continuous flow cell. Data is used to analyze the growth rate dependence on temperature and also to elucidate the effects of dimethylsulfoxide (DMSO) when used as a co-solvent. Activation energies (EA) of ZnOS are calculated for different flow rates and solution compositions. As a result, the measured EA relationships are affected by changes in the primary growth mechanism when DMSO is included.

  15. A quantitative study on the trachea of the dog.

    PubMed

    Dabanoğlu, I; Ocal, M K; Kara, M E

    2001-02-01

    This study was carried out to record the detailed morphometric structure of the trachea in dogs using 15 female and four male healthy adult mongrel dogs. The diameter and thickness of each tracheal ring were measured, the number of tracheal rings varying from 36 to 45. All data were subjected to statistical analysis which was carried out on individual sections of the trachea, i.e. the cranial cervical, middle cervical, thoracic inlet and the intrathoracic tracheal regions, which consisted of 12, 12, nine and 12 tracheal rings, respectively. Fusion of the tracheal rings was especially obvious in the cranial cervical and thoracic inlet regions as a result of neck movements. The diameter and thickness of the tracheal rings are smallest at the thoracic inlet level because the direction of the trachea changes at this point where the thoracic inlet is relatively small and surrounded by bone. The ratios of inner transverse to inner vertical and outer transverse to outer vertical diameters were almost the same, between 1.14 and 1.25 in all regions, which indicated that the trachea is near-circular in shape in the dog. At the thoracic inlet level cross-sectional lumen areas are 7 and 6% smaller than those in the middle cervical and intrathoracic regions, respectively. The thinnest cartilage was seen at the thoracic inlet level where there is a risk of tracheal collapse. PMID:11284164

  16. Quantitative study on the chemical solution deposition of zinc oxysulfide

    DOE PAGESBeta

    Reinisch, Michael; Perkins, Craig L.; Steirer, K. Xerxes

    2015-11-21

    Zinc Oxysulfide (ZnOS) has demonstrated potential in the last decade to replace CdS as a buffer layer material since it is a wide-band-gap semiconductor with performance advantages over CdS (Eg = 2.4 eV) in the near UV-range for solar energy conversion. However, questions remain on the growth mechanisms of chemical bath deposited ZnOS. In this study, a detailed model is employed to calculate solubility diagrams that describe simple conditions for complex speciation control using only ammonium hydroxide without additional base. For these conditions, ZnOS is deposited via aqueous solution deposition on a quartz crystal microbalance in a continuous flow cell.more » Data is used to analyze the growth rate dependence on temperature and also to elucidate the effects of dimethylsulfoxide (DMSO) when used as a co-solvent. Activation energies (EA) of ZnOS are calculated for different flow rates and solution compositions. As a result, the measured EA relationships are affected by changes in the primary growth mechanism when DMSO is included.« less

  17. Quantitative Studies on Fabrics as Disseminators of Viruses

    PubMed Central

    Sidwell, Robert W.; Dixon, Glen J.; Mcneil, Ethel

    1966-01-01

    The persistence of vaccinia virus on wool (blanket and gabardine) and cotton (sheeting, terry cloth, and knit jersey) fabrics was studied. The fabrics were exposed to the virus by three methods: direct contact, aerosol, and virus-containing dust having a high content of textile fibers. Fabrics exposed to virus by each method were held in 35 and 78% relative humidities at 25 C. Virus was recovered for up to 14 weeks from wool fabrics exposed to virus and held in the low humidity. In contrast, virus persisted for shorter periods of time on the cotton fabrics. No virus was detected on terry cloth as early as 3 days after exposure to virus. The virus appeared to be less stable in the high humidity, and the method of exposure of the fabrics to virus apparently had an effect upon the persistence of the agent. On all fabrics, viral persistence was of sufficient duration to be of epidemiological significance. Images Fig. 1 Fig. 2 Fig. 3 Fig. 4 Fig. 5 Fig. 6 PMID:5953019

  18. Geometry of normal mammalian platelets by quantitative microscopic studies.

    PubMed Central

    Frojmovic, M M; Panjwani, R

    1976-01-01

    The shape distributions of normal and hardened human and rabbit erythrocytes and platelets were obtained for edge-on orientations of a few hundred freely rotating cells from analyses of microphotographs obtained similarly as by Ponder(1930, Q. J. Exp. Physiol. 20:29) by phase-contrast microscopy at 800 X magnification. Major average diameters (d) and thicknesses (t) were estimated for both normal and hardened cells, and were used to calculate an average geometric axis ratio, rp = t/d, which increases to unity as cells become more spherical. Our fixation procedure did not alter these shape parameters: rp was unchanged for erythrocytes, with d and t values similar to those reported by Ponder (1930); platelets had d X t = 3.6 +/- 0.7 mum X 0.9 +/- 0.3 mum and 3.1 +/- 0.4 mum X 0.6 +/- 0.3 mum, respectively, for human and rabbit cells, with rp = 0.26 and 0.20, respectively. Agreement in rp was found with data obtained by a novel rheo-optical method which allows for a direct statistical averaging for large populations (greater than 100 X 10(3) cells). Histograms and linear correlation studies were made of the above three parameters (d,t,rp), as well as volume (V), total surface area are (S), and sphericity index (S.I.) calculated for both "prolate ellipsoid" and "disc with rounded edges" models. Results indicate very high linear correlations between rp - t, rp - S. I., and d -S, with high correlations for t - V,d -V and S. Data are in agreement with the few reports in the literature determined by other methods, with the best model for platelets appearing to be an oblate spheroid. Images FIGURE 1A FIGURE 1B FIGURE 2 FIGURE 3 PMID:786400

  19. Quantitative proteomic profiling studies of pancreatic cancer stem cells.

    PubMed

    Dai, Lan; Li, Chen; Shedden, Kerby A; Lee, Cheong J; Li, Chenwei; Quoc, HuyVuong; Simeone, Diane M; Lubman, David M

    2010-07-01

    Analyzing subpopulations of tumor cells in tissue is a challenging subject in proteomic studies. Pancreatic cancer stem cells (CSCs) are such a group of cells that only constitute 0.2-0.8% of the total tumor cells but have been found to be the origin of pancreatic cancer carcinogenesis and metastasis. Global proteome profiling of pancreatic CSCs from xenograft tumors in mice is a promising way to unveil the molecular machinery underlying the signaling pathways. However, the extremely low availability of pancreatic tissue CSCs (around 10,000 cells per xenograft tumor or patient sample) has limited the utilization of currently standard proteomic approaches which do not work effectively with such a small amount of material. Herein, we describe the profiling of the proteome of pancreatic CSCs using a capillary scale shotgun technique by coupling offline capillary isoelectric focusing(cIEF) with nano reversed phase liquid chromatography(RPLC) followed by spectral counting peptide quantification. A whole cell lysate from 10,000 cells which corresponds to approximately 1 microg of protein material is equally divided for three repeated cIEF separations where around 300 ng of peptide material is used in each run. In comparison with a nontumorigenic tumor cell sample, among 1159 distinct proteins identified with FDR less than 0.2%, 169 differentially expressed proteins are identified after multiple testing corrections where 24% of the proteins are upregulated in the CSCs group. Ingenuity Pathway analysis of these differential expression signatures further suggests significant involvement of signaling pathways related to apoptosis, cell proliferation, inflammation, and metastasis. PMID:20486718

  20. Quantitative Study of Vulnerability / Damage Curves in South Africa

    NASA Astrophysics Data System (ADS)

    Pule, Tebogo

    2014-05-01

    Southern Africa is considered a stable continental region in spite of several cases of reported earthquakes, which caused considerable damage and casualties particularly in the mining industry. Most buildings and structures in South Africa are not designed to resist any intensity of earthquake and most architects, engineers and builders in the country do not consider seismic resistance as a design requirement. This is mainly because the region has not experienced any large and serious destructive earthquake in recent years. The most destructive earthquake recorded in South Africa is the Ceres earthquake of 1969. The earthquake with a magnitude of 6.3 occurred on September 29, 1969 in the Ceres-Tulbagh region of the Western Cape Province about 100 km northeast of Cape Town. Serious damage occurred to certain buildings in the area (amounting to a total of U.S. 24 million). The structural damage varied from almost total destruction of old and poorly constructed buildings to large cracks in the better-built ones, twelve people were killed and many more were injured. Another event that caused severe damage to infrastructure occurred on March 9, 2005 at Stilfontein near Klerksdorp. It is known that up to 40 or more tremors are recorded monthly in Southern Africa, the locations are predominantly in the places surrounding the gold mining areas with many events around the Carletonville and Klerksdorp areas. Recent years have seen at least four mining induced tremors causing significant damage (Welkom 1976, Klerksdorp 1977, Welkom 1989 and Carletonville 1992). Such events show that it is very necessary to take seismic events into account in the design of any infrastructure. Assessing and understanding the risk facing the South African cities as a result of major seismic activity has been paid little attention. The main focus of this study is to use results of a deterministic hazard assessment to develop the most suitable damage curves for twelve of the most common building

  1. Radiation dose to positron emission tomography technologists during quantitative versus qualitative studies.

    PubMed

    McCormick, V A; Miklos, J A

    1993-05-01

    Positron emission tomography technologists were monitored with thermoluminescent dosimeters (TLDs) during qualitative and quantitative studies. Doses to technologists during specific tasks were also measured. The technologists received at least twice as much radiation during the quantitative as the qualitative studies. The average dose per study for qualitative studies was 0.017 mSv (1.7 mrem) shallow and 0.014 mSv (1.4 mrem) deep. The average dose per study for the quantitative studies was 0.05 mSv (5 mrem) shallow and 0.04 mSv (4 mrem) deep. The average dose per study was based on the TLD dose accumulated over studies conducted over four 2-mo and one 1-mo intervals. The dose incurred by the technologists each time they drew a radioactive dose was 0.002 mSv (0.2 mrem) shallow and 0.001 mSv (0.1 mrem) deep. The doses received during injection were 0.014 mSv (1.4 mrem) shallow and 0.007 mSv (0.7 mrem) deep. Doses received during blood sampling were 0.016 mSv (1.6 mrem) shallow and 0.014 mSv (1.4 mrem) deep. During quantitative studies, the technologist received a much greater dose than during its qualitative counterpart due to the blood sampling process and increased time in the room with the radioactive patient. PMID:8478709

  2. Worldwide research productivity in the field of electronic cigarette: a bibliometric analysis

    PubMed Central

    2014-01-01

    Background Electronic cigarette (EC) is an emerging phenomenon that is becoming increasingly popular with smokers worldwide. There is a lack of data concerning the evaluation of research productivity in the field of EC originating from the world. The main objectives of this study were to analyse worldwide research output in EC field, and to examine the authorship pattern and the citations retrieved from the Scopus database. Methods Data were searched for documents with specific words regarding EC as “keywords” in the title. Scientific output was evaluated based on the methodology developed and used in other bibliometric studies by investigation: (a) total and trends of contributions in EC research during all previous years up to the date of data analysis (June 13, 2014); (b) authorship patterns and research productivity; (c) countries contribution; and (d) citations received by the publications. Results Three hundred and fifty-six documents were retrieved comprising 31.5% original journal articles, 16% letters to the editor, 7.9% review articles, and 44.6% documents that were classified as other types of publications, such as notes or editorials or opinions. The retrieved documents were published in 162 peer-reviewed journals. All retrieved documents were published from 27 countries. the largest number of publications in the field of EC was from the United States of America (USA); (33.7%), followed by the United Kingdom (UK); (11.5%), and Italy (8.1%). The total number of citations at the time of data analysis was 2.277, with an average of 6.4 citations per document and median (interquartile range) of 0.0 (0.0–5.0). The h-index of the retrieved documents was 27. The most productive institutions were Food and Drug Administration, USA (4.2% of total publications) followed by Universita degli Studi di Catania, Italy (3.9%), University of California, San Francisco, USA (3.7%). Conclusions This bibliometric study is a testament to the progress in EC research from

  3. Qualitative and Quantitative Approaches to the Study of Poverty: Taming the Tensions and Appreciating the Complementarities

    ERIC Educational Resources Information Center

    Balarabe Kura, Sulaiman Y.

    2012-01-01

    There is a germane relationship between qualitative and quantitative approaches to social science research. The relationship is empirically and theoretically demonstrated by poverty researchers. The study of poverty, as argued in this article, is a study of both numbers and contextualities. This article provides a general overview of qualitative…

  4. Leadership Trust in Virtual Teams Using Communication Tools: A Quantitative Correlational Study

    ERIC Educational Resources Information Center

    Clark, Robert Lynn

    2014-01-01

    The purpose of this quantitative correlational study was to address leadership trust in virtual teams using communication tools in a small south-central, family-owned pharmaceutical organization, with multiple dispersed locations located in the United States. The results of the current research study could assist leaders to develop a communication…

  5. Evaluating the Effectiveness of Remedial Reading Courses at Community Colleges: A Quantitative Study

    ERIC Educational Resources Information Center

    Lavonier, Nicole

    2014-01-01

    The present study evaluated the effectiveness of two instructional approaches for remedial reading courses at a community college. The instructional approaches were strategic reading and traditional, textbook-based instruction. The two research questions that guided the quantitative, quasi-experimental study were: (a) what is the effect of…

  6. SAT-M Performance of Women Intending Quantitative Fields of Study.

    ERIC Educational Resources Information Center

    Ethington, Corinna A.

    This study assessed patterns of differences in quantitative performance across groups of intended undergraduate majors consistent with those previously found for students who had completed their undergraduate study. Data were drawn from the College Board Admissions Testing Program's national sample of 10,000 college-bound high school seniors in…

  7. Reverse Brain Drain of South Asian IT Professionals: A Quantitative Repatriation Study

    ERIC Educational Resources Information Center

    Suppiah, Nithiyananthan

    2014-01-01

    The purpose of the present quantitative correlational study was to examine if a relationship existed between the RBD phenomenon and cultural, economic, or political factors of the native countries of South Asian IT professionals living in the United States. The study on reverse brain drain was conducted to explore a growing phenomenon in the…

  8. A Quantitative Comparative Study Measuring Consumer Satisfaction Based on Health Record Format

    ERIC Educational Resources Information Center

    Moore, Vivianne E.

    2013-01-01

    This research study used a quantitative comparative method to investigate the relationship between consumer satisfaction and communication based on the format of health record. The central problem investigated in this research study related to the format of health record used and consumer satisfaction with care provided and effect on communication…

  9. Quantitative Correlational Study: Emotional Intelligence and Project Outcomes among Hispanics in Technology

    ERIC Educational Resources Information Center

    Trejo, Arturo

    2013-01-01

    The present quantitative correlational research study explored relationships between Emotional Intelligence (EI) competencies, such as self-awareness, self-management, social awareness, and relationship management, and project management outcomes: scope creep, in-budget project cost, and project timeliness. The study was conducted within the…

  10. Syntactic Constraints on Code-Switching: A Quantitative Study of Spanish/English.

    ERIC Educational Resources Information Center

    Pfaff, Carol W.

    This paper reports on a preliminary quantitative study of syntactic constraints on code-switching within discourses in which no change in participants, setting or topic is evident. The goals of the study are to provide a syntactic description of the points at which switches from Spanish to English and English to Spanish are possible and to assess…

  11. A quantitative analysis of qualitative studies in clinical journals for the 2000 publishing year

    PubMed Central

    McKibbon, Kathleen Ann; Gadd, Cynthia S

    2004-01-01

    Background Quantitative studies are becoming more recognized as important to understanding health care with all of its richness and complexities. The purpose of this descriptive survey was to provide a quantitative evaluation of the qualitative studies published in 170 core clinical journals for 2000. Methods All identified studies that used qualitative methods were reviewed to ascertain which clinical journals publish qualitative studies and to extract research methods, content (persons and health care issues studied), and whether mixed methods (quantitative and qualitative methods) were used. Results 60 330 articles were reviewed. 355 reports of original qualitative studies and 12 systematic review articles were identified in 48 journals. Most of the journals were in the discipline of nursing. Only 4 of the most highly cited health care journals, based on ISI Science Citation Index (SCI) Impact Factors, published qualitative studies. 37 of the 355 original reports used both qualitative and quantitative (mixed) methods. Patients and non-health care settings were the most common groups of people studied. Diseases and conditions were cancer, mental health, pregnancy and childbirth, and cerebrovascular disease with many other diseases and conditions represented. Phenomenology and grounded theory were commonly used; substantial ethnography was also present. No substantial differences were noted for content or methods when articles published in all disciplines were compared with articles published in nursing titles or when studies with mixed methods were compared with studies that included only qualitative methods. Conclusions The clinical literature includes many qualitative studies although they are often published in nursing journals or journals with low SCI Impact Factor journals. Many qualitative studies incorporate both qualitative and quantitative methods. PMID:15271221

  12. Quantitative and qualitative approaches in the study of poverty and adolescent development: separation or integration?

    PubMed

    Leung, Janet T Y; Shek, Daniel T L

    2011-01-01

    This paper examines the use of quantitative and qualitative approaches to study the impact of economic disadvantage on family processes and adolescent development. Quantitative research has the merits of objectivity, good predictive and explanatory power, parsimony, precision and sophistication of analysis. Qualitative research, in contrast, provides a detailed, holistic, in-depth understanding of social reality and allows illumination of new insights. With the pragmatic considerations of methodological appropriateness, design flexibility, and situational responsiveness in responding to the research inquiry, a mixed methods approach could be a possibility of integrating quantitative and qualitative approaches and offers an alternative strategy to study the impact of economic disadvantage on family processes and adolescent development. PMID:21870673

  13. Quantitative carbon-13 nuclear magnetic resonance spectroscopic study of mobile residues in bacteriorhodopsin

    SciTech Connect

    Bowers, J.L.; Oldfield, E.

    1988-07-12

    The authors have used quantitative carbon-13 nuclear magnetic resonance (NMR) spectroscopy to study the dynamic structure of the backbone of bacteriorhodopsin in the purple membrane of Halobacterium halobium R/sub 1/ and JW-3. NMR experiments were performed using an internal sucrose quantitation standard on purple membranes in which one of the following /sup 13/C'-labeled amino acids had been biosynthetically incorporated: glycine, isoleucine, lysine, phenylalanine, and valine. The results suggest that the C-terminus of the polypeptide chain backbone, and possibly one of the connecting loops, undergoes rapid, large angle fluctuations. The results are compared with previous NMR and fluorescence spectroscopic data obtained on bacteriorhodopsin.

  14. A study of the 42CrMo4 steel surface by quantitative XPS electron spectroscopy

    NASA Astrophysics Data System (ADS)

    Flori, M.; Gruzza, B.; Bideux, L.; Monier, G.; Robert-Goumet, C.

    2008-05-01

    Quantitative X-ray photoelectron spectroscopy was used to characterize the native oxide film formed on 42CrMo4 steel surface by air exposure in normal conditions. In order to determine the thickness and composition of the oxide layer we have used a stacking layer model together with experimental XPS sputtering depth profiling. At a nanoscale study, to obtain quantitative results one must take into account fundamental parameters like the attenuation depth of photoelectrons. We have found that both lepidocrocit (γ-FeOOH) and magnetite (Fe 3O 4) were present and the total thickness of the oxide layer was 16 monolayers.

  15. Economic Evaluation in Global Perspective: A Bibliometric Analysis of the Recent Literature.

    PubMed

    Pitt, Catherine; Goodman, Catherine; Hanson, Kara

    2016-02-01

    We present a bibliometric analysis of recently published full economic evaluations of health interventions and reflect critically on the implications of our findings for this growing field. We created a database drawing on 14 health, economic, and/or general literature databases for articles published between 1 January 2012 and 3 May 2014 and identified 2844 economic evaluations meeting our criteria. We present findings regarding the sensitivity, specificity, and added value of searches in the different databases. We examine the distribution of publications between countries, regions, and health areas studied and compare the relative volume of research with disease burden. We analyse authors' country and institutional affiliations, journals and journal type, language, and type of economic evaluation conducted. More than 1200 economic evaluations were published annually, of which 4% addressed low-income countries, 4% lower-middle-income countries, 14% upper-middle-income countries, and 83% high-income countries. Across country income levels, 53, 54, 86, and 100% of articles, respectively, included an author based in a country within the income level studied. Biomedical journals published 74% of economic evaluations. The volume of research across health areas correlates more closely with disease burden in high-income than in low-income and middle-income countries. Our findings provide an empirical basis for further study on methods, research prioritization, and capacity development in health economic evaluation. PMID:26804359

  16. Productive Factors in School Learning: A Quantitative Synthesis of National Assessment Studies.

    ERIC Educational Resources Information Center

    Borger, Jeanne B.; Walberg, Herbert J.

    To integrate findings concerning the influence of productive factors on student achievement and attitudes across various disciplines and ages, nine regression studies of National Assessment of Educational Progress samples containing a total of 15,802 students were quantitatively synthesized. Correlations and standardized regression weights for…

  17. Measuring the Beginning: A Quantitative Study of the Transition to Higher Education

    ERIC Educational Resources Information Center

    Brooman, Simon; Darwent, Sue

    2014-01-01

    This quantitative study measures change in certain factors known to influence success of first-year students during the transition to higher education: self-efficacy, autonomous learning and social integration. A social integration scale was developed with three subscales: "sense of belonging", "relationship with staff" and…

  18. Leadership Styles at Middle- and Early-College Programs: A Quantitative Descriptive Correlational Study

    ERIC Educational Resources Information Center

    Berksteiner, Earl J.

    2013-01-01

    The purpose of this quantitative descriptive correlational study was to determine if associations existed between middle- and early-college (MEC) principals' leadership styles, teacher motivation, and teacher satisfaction. MEC programs were programs designed to assist high school students who were not served well in a traditional setting (Middle…

  19. Academic Advising and First-Generation College Students: A Quantitative Study on Student Retention

    ERIC Educational Resources Information Center

    Swecker, Hadyn K.; Fifolt, Matthew; Searby, Linda

    2014-01-01

    For this quantitative study, we used a multiple logistic regression technique to investigate the relationship between the number of meetings with an academic advisor and retention of first-generation students, as represented by enrollment status and academic standing at a large, public research institution in the Southeast. Consistent with…

  20. A Quantitative Study of the Relationship between Leadership Practice and Strategic Intentions to Use Cloud Computing

    ERIC Educational Resources Information Center

    Castillo, Alan F.

    2014-01-01

    The purpose of this quantitative correlational cross-sectional research study was to examine a theoretical model consisting of leadership practice, attitudes of business process outsourcing, and strategic intentions of leaders to use cloud computing and to examine the relationships between each of the variables respectively. This study…

  1. Serving Two Masters: A Study of Quantitative Literacy at Small Colleges and Universities

    ERIC Educational Resources Information Center

    Miller, Jodie Ann

    2012-01-01

    The past twenty years have seen a growing interest in promoting quantitative literacy (QL) courses at the college level. At small institutions, financial realities impose limitations on faculty size and therefore the variety of courses that may be offered. This study examined course offerings below calculus at four hundred twenty-eight small…

  2. Exploring the Perceptions of College Instructors towards Computer Simulation Software Programs: A Quantitative Study

    ERIC Educational Resources Information Center

    Punch, Raymond J.

    2012-01-01

    The purpose of the quantitative regression study was to explore and to identify relationships between attitudes toward use and perceptions of value of computer-based simulation programs, of college instructors, toward computer based simulation programs. A relationship has been reported between attitudes toward use and perceptions of the value of…

  3. A Quantitative Study Examining Teacher Stress, Burnout, and Self-Efficacy

    ERIC Educational Resources Information Center

    Stephenson, Timar D.

    2012-01-01

    The purpose of this quantitative, correlational study was to examine the relationships between stress, burnout, and self-efficacy in public school teachers in the Turks and Caicos Islands. The Teacher Stress Inventory was used to collect data on teacher stress, the Maslach Burnout Inventory Educators Survey was used to obtain data on teacher…

  4. A Quantitative Study of the Effectiveness of Teacher Recruitment Strategies in a Rural Midwestern State

    ERIC Educational Resources Information Center

    Kane, Rose Etta

    2010-01-01

    A problem in American education is that rural schools have difficulty recruiting licensed teachers. Teacher shortages in mathematics, science, foreign language, and special education are more acute in rural areas. The purpose of this quantitative descriptive survey study was to examine specific recruiting strategies and newly hired licensed…

  5. A QUANTITATIVE APPROACH FOR ESTIMATING EXPOSURE TO PESTICIDES IN THE AGRICULTURAL HEALTH STUDY

    EPA Science Inventory

    We developed a quantitative method to estimate chemical-specific pesticide exposures in a large prospective cohort study of over 58,000 pesticide applicators in North Carolina and Iowa. An enrollment questionnaire was administered to applicators to collect basic time- and inten...

  6. An Exploratory Study of "Quantitative Linguistic Feedback": Effect of LENA Feedback on Adult Language Production

    ERIC Educational Resources Information Center

    Suskind, Dana; Leffel, Kristin R.; Hernandez, Marc W.; Sapolich, Shannon G.; Suskind, Elizabeth; Kirkham, Erin; Meehan, Patrick

    2013-01-01

    A child's early language environment is critical to his or her life-course trajectory. Quantitative linguistic feedback utilizes the Language ENvironment Analysis (LENA) technology as a tool to analyze verbal interactions and reinforce behavior change. This exploratory pilot study evaluates the feasibility and efficacy of a novel…

  7. A Study to Formulate Quantitative Guidelines for the Audio-Visual Communications Field. Final Report.

    ERIC Educational Resources Information Center

    Faris, Gene; Sherman, Mendel

    Quantitative guidelines for use in determining the audiovisual (AV) needs of educational institutions were developed by the Octobe r 14-16, 1965 Seminar of the NDEA (National Defense Education Act), Faris-Sherman study. The guidelines that emerged were based in part on a review of past efforts and existing standards but primarily reflected the…

  8. Effects of Drawing on Alpha Activity: A Quantitative EEG Study with Implications for Art Therapy

    ERIC Educational Resources Information Center

    Belkofer, Christopher M.; Van Hecke, Amy Vaughan; Konopka, Lukasz M.

    2014-01-01

    Little empirical evidence exists as to how materials used in art therapy affect the brain and its neurobiological functioning. This pre/post within-groups study utilized the quantitative electroencephalogram (qEEG) to measure residual effects in the brain after 20 minutes of drawing. EEG recordings were conducted before and after participants (N =…

  9. Process analytical technology case study part I: feasibility studies for quantitative near-infrared method development.

    PubMed

    Cogdill, Robert P; Anderson, Carl A; Delgado-Lopez, Miriam; Molseed, David; Chisholm, Robert; Bolton, Raymond; Herkert, Thorsten; Afnán, Ali M; Drennen, James K

    2005-01-01

    This article is the first of a series of articles detailing the development of near-infrared (NIR) methods for solid-dosage form analysis. Experiments were conducted at the Duquesne University Center for Pharmaceutical Technology to qualify the capabilities of instrumentation and sample handling systems, evaluate the potential effect of one source of a process signature on calibration development, and compare the utility of reflection and transmission data collection methods. A database of 572 production-scale sample spectra was used to evaluate the interbatch spectral variability of samples produced under routine manufacturing conditions. A second database of 540 spectra from samples produced under various compression conditions was analyzed to determine the feasibility of pooling spectral data acquired from samples produced at diverse scales. Instrument qualification tests were performed, and appropriate limits for instrument performance were established. To evaluate the repeatability of the sample positioning system, multiple measurements of a single tablet were collected. With the application of appropriate spectral preprocessing techniques, sample repositioning error was found to be insignificant with respect to NIR analyses of product quality attributes. Sample shielding was demonstrated to be unnecessary for transmission analyses. A process signature was identified in the reflection data. Additional tests demonstrated that the process signature was largely orthogonal to spectral variation because of hardness. Principal component analysis of the compression sample set data demonstrated the potential for quantitative model development. For the data sets studied, reflection analysis was demonstrated to be more robust than transmission analysis. PMID:16353986

  10. Bibliometric analysis of global environmental assessment research in a 20-year period

    SciTech Connect

    Li, Wei Zhao, Yang

    2015-01-15

    Based on the samples of 113,468 publications on environmental assessment (EA) from the past 20 years, we used a bibliometric analysis to study the literature in terms of trends of growth, subject categories and journals, international collaboration, geographic distribution of publications, and scientific research issues. By applying thresholds to network centralities, a core group of countries can be distinguished as part of the international collaboration network. A frequently used keywords analysis found that the priority in assessment would gradually change from project environmental impact assessment (EIA) to strategic environmental assessment (SEA). Decision-theoretic approaches (i.e., environmental indicator selection, life cycle assessment, etc.), along with new technologies and methods (i.e., the geographic information system and modeling) have been widely applied in the EA research field over the past 20 years. Hot spots such as “biodiversity” and “climate change” have been emphasized in current EA research, a trend that will likely continue in the future. The h-index has been used to evaluate the research quality among countries all over the world, while the improvement of developing countries' EA systems is becoming a popular research topic. Our study reveals patterns in scientific outputs and academic collaborations and serves as an alternative and innovative way of revealing global research trends in the EA research field.

  11. Hot topics and application trends of the anammox biotechnology: a review by bibliometric analysis.

    PubMed

    Zhang, Zuotao; Liu, Sitong

    2014-01-01

    Anammox has been extensively identified as a novel and sustained biotechnology for wastewater treatment. This study was conducted to evaluate the hot topics and application trends of anammox biotechnology by bibliometric analysis. The results show that "Water science and technology" and "Environmental science ecology" are the prevalent journal and category in this field. Many researches about "process" and "inhibition" have been carried out to conquer common challenges of anammox biotechnology in its actual engineering application. "Fluorescence in situ hybridization" continues to be the leading rRNA microbiological analysis method after its first application. Most importantly, "Completely autotrophic nitrogen removal over nitrite (CANON)", "Sequencing batch reactors (SBR) for anammox operation", "black water treatment" and "anammox biofilm" are identified as the prevalent process type, reactor type, wastewater type and bacterial aggregation form in anammox research currently, which forecasts the further engineering application direction of anammox biotechnology. The study will be useful for the researchers to acquaint the current state and the application trends in anammox biotechnology field. PMID:24855588

  12. The top cited clinical research articles on sepsis: a bibliometric analysis

    PubMed Central

    2012-01-01

    Introduction The objective of this study was to identify and characterize the most highly cited clinical research articles published on sepsis. Methods A comprehensive list of citation classics in sepsis was generated by searching the database of Web of Science-Expanded (1970 to present) using keywords 'sepsis' or 'septic shock'. The top 50 cited clinical research papers were retrieved by reading the abstract or full text if needed. Each eligible article was reviewed for basic information, including country of origin, article type, journals, authors, and funding sources. Results A total of 2,151 articles were cited more than 100 times; the 50 top-cited clinical articles were published between 1974 and 2008. The number of citations ranged from 372 to 2,932, with a mean of 678 citations per article. These citation classics came from nine countries, of which 26 articles came from the United States. Rush University and the University of Pittsburgh lead the list of classics with six papers each. The 50 top-cited articles were published in 17 journals, with the New England Journal of Medicine and Journal of the American Medical Association topping the list. The top 50 articles consisted of 21 clinical trials and 29 observational studies. Conclusions Our bibliometric analysis provides a historical perspective on the progress of clinical research on sepsis. Articles originating from the United States and published in high-impact journals are most likely to be cited in the field of sepsis research. PMID:22731930

  13. Bibliometric assessment of the contributions of literature on Chagas disease in Latin America and the Caribbean.

    PubMed

    Delgado-Osorio, Nathalia; Vera-Polania, Felipe; Lopez-Isaza, Andres F; Martinez-Pulgarin, Dayron F; Murillo-Abadia, Jonathan; Munoz-Urbano, Marcela; Cardona-Ospina, Jaime A; Bello, Ricardo; Lagos-Grisales, Guillermo J; Villegas-Rojas, Soraya; Rodriguez-Morales, Alfonso J

    2014-01-01

    Chagas disease, considered a parasitic neglected disease, is endemic in Latin America. Although, its mortality rate has decreased over time, it still represents a public health problem in the region. A bibliometric evaluation of the Latin American contributions on this disease was done. This study used SCI (1980-2013), MEDLINE/GOPUBMED (1802-2013), Scopus (1959-2013), SCIELO (2004-2013), and LILACS (1980-2013). Different study types have been characterized by years, origin city/country, journals and most productive authors, by country, cites and H-index. 2988 articles were retrieved from SCI (30.85% of total). Brazil was found to be the highest producer (31.22%), followed by Argentina (18.14%) and México (9.57%); the region received 47241 citations, 28.60% for Brazil (H-index=52), 18.26% of Argentina (Hindex= 43), 11.40% Bolivia (H-index=37). 4484 were retrieved from Scopus (30.20% of the total), 38.58% of which were from Brazil, 12.40% from Argentina and 8.90% from Mexico. From Medline, 6647 records were retrieved (45.58% Brazil). From SciELO, 917 articles (47.66% Brazil). From LILACS, 2165 articles (60.05% Brazil). Brazil has the highest output in the region. Despite advances in controlling Chagas disease, scientific production is low, particularly for regional bibliographic databases, which calls for more research on this disease. PMID:25858262

  14. Mapping of drinking water research: a bibliometric analysis of research output during 1992-2011.

    PubMed

    Fu, Hui-Zhen; Wang, Ming-Huang; Ho, Yuh-Shan

    2013-01-15

    A bibliometric analysis based on the Science Citation Index Expanded from the Web of Science was carried out to provide insights into research activities and tendencies of the global drinking water from 1992 to 2011. Study emphases included performance of publication covering annual outputs, mainstream journals, Web of Science categories, leading countries, institutions, research tendencies and hotspots. The results indicated that annual output of the related scientific articles increased steadily. Water Research, Environmental Science & Technology, and Journal American Water Works Association were the three most common journals in drinking water research. The USA took a leading position out of 168 countries/territories, followed by Japan and Germany. A summary of the most frequently used keywords obtained from words in paper title analysis, author keyword analysis and KeyWords Plus analysis provided the clues to discover the current research emphases. The mainstream research related to drinking water was water treatment methods and the related contaminants. Disinfection process and consequent disinfection by-products attracted much attention. Ozonation and chlorination in disinfection, and adsorption were common techniques and are getting popular. Commonly researched drinking water contaminants concerned arsenic, nitrate, fluoride, lead, and cadmium, and pharmaceuticals emerged as the frequently studied contaminants in recent years. Disease caused by contaminants strongly promoted the development of related research. PMID:23228721

  15. Strategies to recruit and retain older adults in intervention studies: a quantitative comparative study.

    PubMed

    Michelet, Mona; Lund, Anne; Sveen, Unni

    2014-01-01

    Recruitment and retention of participants in randomized controlled trials (RCTs) drawn from the older population is challenging, and studies have shown that poor recruitment and retention may lead to biased samples and results. Several strategies to improve the participation of older adults in research are outlined in the literature. The objective was to identify factors associated with participation in an RCT aiming at preventing depressive symptoms and social isolation in a later phase following a stroke, in an older population living in their homes. Strategies to improve participation were applied in the RCT "Lifestyle intervention for older adults in rehabilitation after stroke: development, implementation and evaluation". Quantitative data collected on participants (n=99) and non-participants (n=56) in the trial were compared using statistical analyses. The findings are in line with earlier studies in that the participants were younger (p=0.01) and received less help in the home (p=0.01) than did non-participants. The results differ from earlier studies in that participants had a higher rate of depressive symptoms (participation rate was 57% with HAD depression scale score 0-2, 61% with score 3-4, 62% with score 5-6 and 79% with a score 7 or above). The findings also illustrate a poorer health-related quality of life among the participants in the role physical domain on Short Form-36 (p=0.01). The results indicate that the use of targeted strategies to enhance participation may lead to a less biased sample as well as the inclusion of more subjects who seem to meet the aims of the intervention. PMID:24698174

  16. Anatomy of the ICDS series: A bibliometric analysis

    NASA Astrophysics Data System (ADS)

    Cardona, Manuel; Marxa, Werner

    2007-12-01

    In this article, the proceedings of the International Conferences on Defects in Semiconductors (ICDS) have been analyzed by bibliometric methods. The papers of these conferences have been published as articles in regular journals or special proceedings journals and in books with diverse publishers. The conference name/title changed several times. Many of the proceedings did not appear in the so-called “source journals” covered by the Thomson/ISI citation databases, in particular by the Science Citation Index (SCI). But the number of citations within these source journals can be determined using the Cited Reference Search mode under the Web of Science (WoS) and the SCI offered by the host STN International. The search functions of both systems were needed to select the papers published as different document types and to cover the full time span of the series. The most cited ICDS papers were identified, and the overall numbers of citations as well as the time-dependent impact of these papers, of single conferences, and of the complete series, was established. The complete of citing papers was analyzed with respect to the countries of the citing authors, the citing journals, and the ISI subject categories.

  17. Bibliometric trend and patent analysis in nano-alloys research for period 2000-2013.

    PubMed

    Živković, Dragana; Niculović, Milica; Manasijević, Dragan; Minić, Duško; Ćosović, Vladan; Sibinović, Maja

    2015-01-01

    This paper presents an overview of current situation in nano-alloys investigations based on bibliometric and patent analysis. Bibliometric analysis data, for the period 2000 to 2013, were obtained using Scopus database as selected index database, whereas analyzed parameters were: number of scientific papers per year, authors, countries, affiliations, subject areas and document types. Analysis of nano-alloys patents was done with specific database, using the International Patent Classification and Patent Scope for the period 2003 to 2013. Information found in this database was the number of patents, patent classification by country, patent applicators, main inventors and publication date. PMID:27009127

  18. Bibliometric Analyses of Physical and Occupational Therapy Faculty across Canada Indicate Productivity and Impact of Rehabilitation Research

    PubMed Central

    Fung, Eunice H.; Law, Mary

    2015-01-01

    ABSTRACT Purpose: This study examines physical and occupational therapy faculty across Canada, using bibliometrics and federal funding as indicators of academic impact, and considers the validity of various bibliometric indices. Methods: Faculty members were identified and their rank, professional designation, and department obtained from faculty Web sites. Bibliometric indicators were determined using Publish or Perish software. An independent author (not a faculty member) inspected the data to remove any incorrectly attributed publications. The h-index, citation years, g-index, and total number of citations for each faculty member were retrieved. The Canadian Institutes of Health Research (CIHR) funding database was used to determine the amount of research funding provided to each faculty member as a principal investigator (PI) and his or her total CIHR funding received. Mean faculty indicators by university, rank, gender, and profession were determined. Analysis of variance (ANOVA) was used to detect differences by rank and gender, and measures of association (Pearson correlation coefficients and multiple regression) were used to identify factors that affected h-index and PI funding received. Results: A total of 347 physical and occupational therapy faculty were identified. The median h-index was 5 (inter-quartile range [IQR] 2–8) for assistant professors, 11 (IQR 7–15) for associate professors, and 18 (IQR 12–26) for full professors. ANOVA indicated no significant differences between male and female faculty in terms of h-index or funding received. Regression analysis indicated that 58% of h-index variance could be explained by gender (p=0.039), appointment within a department that provides a (rehabilitation science) PhD programme (p<0.001), rank (p<0.001), CIHR PI funding (p=0.001), or total CIHR funding (p<0.001). Significant predictors of the amount of CIHR funding received as a PI included h-index (p<0.001) and total number of citations (p=0

  19. Bibliometric analysis of nanotechnology applied in oncology from 2002 to 2011.

    PubMed

    Dong, Xifeng; Qiu, Xiao-chun; Liu, Qian; Jia, Jack

    2013-12-01

    Innovation in the last decade has endowed nanotechnology with an assortment of tools for drug delivery system, imaging, and sensing in cancer research. These rapidly emerging tools are indicative of a burgeoning field ready to expand into medical applications. The aim of this study is to analyze the applications of nanotechnology in oncology with bibliometric methods and evaluate development in this field. Literature search was performed using PubMed search engines with MeSH terms (all)--nanotechnology, nanomedicine, nanoparticle, nanocapsules, micellar systems, and oncology or cancer or neoplasms. Within 2,543 articles from 2002 to 2011 in over 50 medical magazines from over 30 countries, we did a series analysis on these articles' countries, keywords, and authors. Our results show that articles in nanotechnology in oncology are increasing year by year, especially in recent years. Quantity and quality of the articles are becoming more and influential. In the global research, the USA is leading in this field, accounting for half above of the whole articles, followed by countries like Japan, Germany, and France and also some emerging nations like China, in the second place, and India. Subjects like nanoparticles, tumor marker, and drug delivery are the common research focus. So, with more and more scientists' interests and attention drawn to this field, it is likely to make major breakthroughs in the coming years. PMID:23959469

  20. Trends in the growth of literature of telemedicine: A bibliometric analysis.

    PubMed

    Yang, Ya-Ting; Iqbal, Usman; Ching, Jack Horn-Yu; Ting, Jonathan Bee-Shen; Chiu, Hsien-Tsai; Tamashiro, Hiko; Hsu, Yi-Hsin Elsa

    2015-12-01

    Over the past two decades, the use of telemedicine as a way to provide medical services has grown as communication technologies advance and patients seek more convenient ways to receive care. Because developments within this field are still rapidly evolving, identifying trends within telemedicine literature is an important task to help delineate future directions of telemedicine research. In this study, we analyzed 7960 telemedicine-related publication records found in the Science Citations Index - Expanded database between 1993 and 2012. Bibliometric analyses revealed that while the total growth in telemedicine literature has been significant in the last twenty years, the publication activity per country and over time has been variable. While the United States led the world in the cumulative number of telemedicine publications, Norway ranked highest when we ordered countries by publications per capita. We also saw that the growth in the number of publications per year has been inconsistent over the past two decades. Our results identified that neuroscience neurology and nursing as two fields of research in telemedicine that have seen considerable growth in interest in this field, and are poised to be the focus of research activity in the near future. PMID:26415760

  1. An agent-based model for the bibliometric h-index

    NASA Astrophysics Data System (ADS)

    Ionescu, Georgia; Chopard, Bastien

    2013-10-01

    We model a virtual scientific community in which authors publish and cite articles. Citations are attributed according to a preferential attachment mechanism. From the numerical simulations, the h-index can be computed. This bottom-up approach reproduces well real bibliometric data. We consider two versions of our model. (1) The single-scientist is controlled by two parameters which can be tuned to reproduce the value of the h-index of many real scientists. Moreover, this model shows how the h-index grows with the number of citations, for a fixed number of articles. We also define an average h-index that can be used to compare the scientific productivity of institutions of different sizes. (2) The multi-scientist model considers a population of scientists and allows us to study the impact of removing citations from the low h-index researchers on the community. Simulations on real bibilometric data, as well as the predictions of the model, show that the h-index eco-system can be strongly affected by such a filtering.

  2. Bibliometric analysis of research on regenerative periodontal surgery during the last 30 years

    PubMed Central

    Gutiérrez-Vela, María M.; Díaz-Haro, Ana; Berbel-Salvador, Sonia; Lucero-Sánchez, Aldo; Cutando-Soriano, Antonio

    2012-01-01

    Objectics: The evolution of research activity during the last thirty years on regenerative periodontal surgery is studied. Results: A small number of authors are highly productive with more than 10 publications on the subject each. 79,6% of authors have only produced one article on the subject. The co-authorship average is of 2,68 authors per paper, with a collaboration between 2 and 6 authors. Main journals on the field of regenerative periodontal surgery are Journal of Periodontology and Journal of Clinical Periodontology, which are ranked 14th and 1st in their category according to the Journal Citations Reports. The most used language is English, followed by Japanese and Italian, Spanish occupying the eighth position. Conclusions: A significant increase on scientific literature is observed, similar to the one Dentistry has had. A reduced number of authors account for most production. In the same token, there is a scarce professionalization of researchers in this field, where most of the authors are occasional. On the other hand, there are two very specialized journals on this topic. Key words:Bibliometrics, scientometrics periodontal regeneration, surgical periodontal treatment, scientific literature, scopus, scientific output. PMID:24558535

  3. On Track to Professorship? A Bibliometric Analysis of Early Scholarly Output.

    PubMed

    Milone, Michael T; Bernstein, Joseph

    2016-01-01

    Academic productivity, demonstrated by a record of scholarly publication, is the main criterion for academic promotion. Nevertheless, there are no data on early-career productivity milestones to guide young faculty members aspiring to attain professor status. We performed a bibliometric analysis to determine the number of scholarly papers published by current professors of orthopedic surgery within 5 years after their having acquired American Board of Orthopaedic Surgery certification (termed early scholarly output). Median early scholarly output for all professors (N = 108) was 11 publications. We found medians of 5 first-author and 2 last-author publications, and 4 publications in Clinical Orthopaedics and Related Research or Journal of Bone and Joint Surgery. Median number of papers cited at least 50 times by year 5 was 2. The median number of total citations was 29.5, and median Hirsch index (h-index) was 3. Faculty who were clinical professors published fewer papers and acquired fewer citations than faculty who were promoted but did have the clinical descriptor. Professors certified after 1995 were more productive than those certified before 1990. This descriptive study provided benchmark data on early scholarly productivity of current professors of orthopedic surgery and demonstrated this benchmark has risen in more recent years. PMID:26991577

  4. Quantitative Phase Imaging Techniques for the Study of Cell Pathophysiology: From Principles to Applications

    PubMed Central

    Lee, KyeoReh; Kim, Kyoohyun; Jung, Jaehwang; Heo, JiHan; Cho, Sangyeon; Lee, Sangyun; Chang, Gyuyoung; Jo, YoungJu; Park, Hyunjoo; Park, YongKeun

    2013-01-01

    A cellular-level study of the pathophysiology is crucial for understanding the mechanisms behind human diseases. Recent advances in quantitative phase imaging (QPI) techniques show promises for the cellular-level understanding of the pathophysiology of diseases. To provide important insight on how the QPI techniques potentially improve the study of cell pathophysiology, here we present the principles of QPI and highlight some of the recent applications of QPI ranging from cell homeostasis to infectious diseases and cancer. PMID:23539026

  5. Twenty years of global groundwater research: A Science Citation Index Expanded-based bibliometric survey (1993-2012)

    NASA Astrophysics Data System (ADS)

    Niu, Beibei; Loáiciga, Hugo A.; Wang, Zhen; Zhan, F. Benjamin; Hong, Song

    2014-11-01

    A bibliometric analysis was conducted to evaluate groundwater research from different perspectives in the period 1993-2012 based on the Science Citation Index-Expanded (SCIE) database. The bibliometric analysis summarizes output, categorical, geographical, and institutional patterns, as well as research hotspots in global groundwater studies. Groundwater research experienced notable growth in the past two decades. “Environmental sciences”, “water resources” and “multidisciplinary geosciences” were the three major subject categories. The Journal of Hydrology published the largest number of groundwater-related publications in the surveyed period. Major author clusters and research regions are located in the United States, Western Europe, Eastern and Southern Asia, and Eastern Australia. The United States was a leading contributor to global groundwater research with the largest number of independent and collaborative papers, its dominance affirmed by housing 12 of the top 20 most active institutions reporting groundwater-related research. The US Geological Survey, the Chinese Academy of Sciences, and the USDA Agricultural Research Service were the three institutions with the largest number of groundwater-related publications. A keywords analysis revealed that groundwater quality and contamination, effective research technologies, and treatment technologies for water-quality improvement were the main research areas in the study period. Several keywords such as “arsenic”, “climate change”, “fluoride”, “groundwater management”, “hydrogeochemistry”, “uncertainty”, “numerical modeling”, “seawater intrusion”, “adsorption”, “remote sensing”, “land use”, “USA”(as study site), and “water supply” received dramatically increased attention during the study period, possibly signaling future research trends.

  6. Annotation of loci from genome-wide association studies using tissue-specific quantitative interaction proteomics.

    PubMed

    Lundby, Alicia; Rossin, Elizabeth J; Steffensen, Annette B; Acha, Moshe Rav; Newton-Cheh, Christopher; Pfeufer, Arne; Lynch, Stacey N; Olesen, Søren-Peter; Brunak, Søren; Ellinor, Patrick T; Jukema, J Wouter; Trompet, Stella; Ford, Ian; Macfarlane, Peter W; Krijthe, Bouwe P; Hofman, Albert; Uitterlinden, André G; Stricker, Bruno H; Nathoe, Hendrik M; Spiering, Wilko; Daly, Mark J; Asselbergs, Folkert W; van der Harst, Pim; Milan, David J; de Bakker, Paul I W; Lage, Kasper; Olsen, Jesper V

    2014-08-01

    Genome-wide association studies (GWAS) have identified thousands of loci associated with complex traits, but it is challenging to pinpoint causal genes in these loci and to exploit subtle association signals. We used tissue-specific quantitative interaction proteomics to map a network of five genes involved in the Mendelian disorder long QT syndrome (LQTS). We integrated the LQTS network with GWAS loci from the corresponding common complex trait, QT-interval variation, to identify candidate genes that were subsequently confirmed in Xenopus laevis oocytes and zebrafish. We used the LQTS protein network to filter weak GWAS signals by identifying single-nucleotide polymorphisms (SNPs) in proximity to genes in the network supported by strong proteomic evidence. Three SNPs passing this filter reached genome-wide significance after replication genotyping. Overall, we present a general strategy to propose candidates in GWAS loci for functional studies and to systematically filter subtle association signals using tissue-specific quantitative interaction proteomics. PMID:24952909

  7. Annotation of loci from genome-wide association studies using tissue-specific quantitative interaction proteomics

    PubMed Central

    Lundby, Alicia; Rossin, Elizabeth J.; Steffensen, Annette B.; Rav Acha, Moshe; Newton-Cheh, Christopher; Pfeufer, Arne; Lynch, Stacey N.; Olesen, Søren-Peter; Brunak, Søren; Ellinor, Patrick T.; Jukema, J.Wouter; Trompet, Stella; Ford, Ian; Macfarlane, Peter W.; Krijthe, Bouwe P.; Hofman, Albert; Uitterlinden, Andre G.; Stricker, Bruno H.; Nathoe, Hendrik M.; Spiering, Wilko; Daly, Mark J.; Asselbergs, Folkert W.; van der Harst, Pim; Milan, David J.; de Bakker, Paul I.W.; Lage, Kasper; Olsen, Jesper V.

    2014-01-01

    Genome-wide association studies (GWAS) have identified thousands of loci associated wtih complex traits, but it is challenging to pinpoint causal genes in these loci and to exploit subtle association signals. We used tissue-specific quantitative interaction proteomics to map a network of five genes involved in the Mendelian disorder long QT syndrome (LQTS). We integrated the LQTS network with GWAS loci from the corresponding common complex trait, QT interval variation, to identify candidate genes that were subsequently confirmed in Xenopus laevis oocytes and zebrafish. We used the LQTS protein network to filter weak GWAS signals by identifying single nucleotide polymorphisms (SNPs) in proximity to genes in the network supported by strong proteomic evidence. Three SNPs passing this filter reached genome-wide significance after replication genotyping. Overall, we present a general strategy to propose candidates in GWAS loci for functional studies and to systematically filter subtle association signals using tissue-specific quantitative interaction proteomics. PMID:24952909

  8. Making Sense of Qualitative and Quantitative Findings in Mixed Research Synthesis Studies

    PubMed Central

    VOILS, CORRINE I.; SANDELOWSKI, MARGARETE; BARROSO, JULIE; HASSELBLAD, VICTOR

    2008-01-01

    The synthesis of qualitative and quantitative research findings is increasingly promoted, but many of the conceptual and methodological issues it raises have yet to be fully understood and resolved. In this article, we describe how we handled issues encountered in efforts to synthesize the findings in forty-two reports of studies of antiretroviral adherence in HIV-positive women in the course of an ongoing study to develop methods to synthesize qualitative and quantitative research findings in common domains of health-related research. Working with these reports underscored the importance of looking past method claims and ideals and directly at the findings themselves, differentiating between aggregative syntheses in which findings are assimilated and interpretive syntheses in which they are configured, and understanding the judgments involved in designating relationships between findings as confirmatory, divergent, or complementary. PMID:18677415

  9. A Comparison of Psychiatry and Internal Medicine: A Bibliometric Study

    ERIC Educational Resources Information Center

    Stone, Karina; Whitham, Elizabeth A.; Ghaemi, S. Nassir

    2012-01-01

    Objective: Psychiatric education needs to expose students to a broad range of topics. One resource for psychiatric education, both during initial training and in later continuing medical education, is the scientific literature, as published in psychiatric journals. The authors assessed current research trends in psychiatric journals, as compared…

  10. Bibliometric analysis of leishmaniasis research in Medline (1945-2010)

    PubMed Central

    2013-01-01

    Background Publications are often used as a measure of success of research work. Leishmaniasis is considered endemic in 98 countries, most of which are developing. This article describes a bibliometric review of the literature on leishmaniasis research indexed in PubMed during a 66-year period. Methods Medline was used via the PubMed online service of the US National Library of Medicine. The search strategy was Leishmania [MeSH] or leishmaniasis [MeSH] from 1 January 1945 until 31 December 2010. Neither language nor document type restrictions were employed. Results A total of 20,780 references were retrieved. The number of publications increased steadily over time, with 3,380 publications from 1945-1980 to 8,267 from 2001-2010. Leishmaniasis documents were published in 1,846 scientific journals, and Transactions of the Royal Society of Tropical Medicine and Hygiene (4.9%) was the top one. The USA was the predominant country by considering the first author’s institutional address (16.8%), followed by Brazil (14.9%), and then India (9.0%), however Brazil leads the scientific output in 2001-2010 period (18.5%), followed by the USA (13.5%) and India (10%). The production ranking changed when the number of publications was normalised by population (Israel and Switzerland), by gross domestic product (Nepal and Tunisia), and by gross national income per capita (India and Ethiopia). For geographical area, Europe led (31.7%), followed by Latin America (24.5%). Conclusions We have found an increase in the number of publications in the field of leishmaniasis. The USA and Brazil led scientific production on leishmaniasis research. PMID:23497410

  11. Research on Social Work Practice: A Bibliometric Evaluation of the First Decade

    ERIC Educational Resources Information Center

    Holden, Gary; Rosenberg, Gary; Barker, Kathleen; Lioi, Justin

    2010-01-01

    Objective: This article describes a bibliometric analysis of articles appearing in the journal "Research on Social Work Practice" (RSWP). Method: Descriptive and predictive analyses for the sample of 322 articles are presented. Results: The typical RSWP article was 15 pages long, had two authors and 28 references, and was cited for the first time…

  12. Using Citation Indexes, Citation Searching, and Bibliometrics to Improve Chemistry Scholarship, Research, and Administration

    ERIC Educational Resources Information Center

    Buntrock, Robert E.

    2016-01-01

    Citation searching and bibliometrics are terms foreign to many chemists and educators, yet well-known and used by librarians and information specialists. This article aims to help chemistry students, educators, and other readers of this "Journal" to better appreciate and use these powerful and profound methods. Although these subjects…

  13. Inciting the Metric Oriented Humanist: Teaching Bibliometrics in a Faculty of Humanities

    ERIC Educational Resources Information Center

    Zuccala, Alesia

    2016-01-01

    In the past few decades the core of bibliometrics has predominantly been "scientometric" in nature, due to the first commercial citation index having been created for scientific journals and articles. The production of citation indexes for books implies that proper education related to their use is now becoming critical. A new breed of…

  14. The Use of Bibliometrics to Measure Research Performance in Education Sciences

    ERIC Educational Resources Information Center

    Diem, Andrea; Wolter, Stefan C.

    2013-01-01

    This paper investigates the fitness-for-purpose and soundness of bibliometric parameters for measuring and elucidating the research performance of individual researchers in the field of education sciences in Switzerland. In order to take into account the specificities of publication practices of researchers in education sciences, the analyses are…

  15. Some Limitations of the "H" Index: A Commentary on Ruscio and Colleagues' Analysis of Bibliometric Indices

    ERIC Educational Resources Information Center

    Waltman, Ludo; Costas, Rodrigo; van Eck, Nees Jan

    2012-01-01

    The literature on bibliometric indices for assessing scholarly impact, in particular the "h" index (Hirsch, 2005) and its many variants, is extensive, but nevertheless Ruscio and colleagues (this issue) succeed in making a valuable contribution. They have made the effort of collecting publication and citation data for no less than 1,750…

  16. Bibliometrics of the World Wide Web: An Exploratory Analysis of the Intellectual Structure of Cyberspace.

    ERIC Educational Resources Information Center

    Larson, Ray R.

    1996-01-01

    Examines the bibliometrics of the World Wide Web based on analysis of Web pages collected by the Inktomi "Web Crawler" and on the use of the DEC AltaVista search engine for cocitation analysis of a set of Earth Science related Web sites. Looks at the statistical characteristics of Web documents and their hypertext links, and the characteristics of…

  17. Exploring metabolism flexibility in complex organisms through quantitative study of precursor sets for system outputs

    PubMed Central

    2014-01-01

    Background When studying metabolism at the organ level, a major challenge is to understand the matter exchanges between the input and output components of the system. For example, in nutrition, biochemical models have been developed to study the metabolism of the mammary gland in relation to the synthesis of milk components. These models were designed to account for the quantitative constraints observed on inputs and outputs of the system. In these models, a compatible flux distribution is first selected. Alternatively, an infinite family of compatible set of flux rates may have to be studied when the constraints raised by observations are insufficient to identify a single flux distribution. The precursors of output nutrients are traced back with analyses similar to the computation of yield rates. However, the computation of the quantitative contributions of precursors may lack precision, mainly because some precursors are involved in the composition of several nutrients and because some metabolites are cycled in loops. Results We formally modeled the quantitative allocation of input nutrients among the branches of the metabolic network (AIO). It corresponds to yield information which, if standardized across all the outputs of the system, allows a precise quantitative understanding of their precursors. By solving nonlinear optimization problems, we introduced a method to study the variability of AIO coefficients when parsing the space of flux distributions that are compatible with both model stoichiometry and experimental data. Applied to a model of the metabolism of the mammary gland, our method made it possible to distinguish the effects of different nutritional treatments, although it cannot be proved that the mammary gland optimizes a specific linear combination of flux variables, including those based on energy. Altogether, our study indicated that the mammary gland possesses considerable metabolic flexibility. Conclusion Our method enables to study the

  18. [Anales de Medicina Interna: standardization, dissemination and bibliometric indicators. (II) Bibliometric analysis].

    PubMed

    Jiménez-Contreras, E; Delgado López-Cozar, E; Ruiz Pérez, R

    1997-08-01

    National and international diffusion, composition of the collective of authors who publish in the journal, and cocitation were studies for the journal An. Med. Interna. Diffusion was analyzed by examining the presence of the journal in medical data bases and specialized libraries in Spain. The institutional affiliations and geographical location of authors were determined on the basis of the affiliations given in the article by-lines. The journal is included in the major medical data bases and in approximately 80% of the libraries studied. The predominant professional affiliation among authors was clinical (hospital); the geographical origin of the authors (expressed as a percentage of all authors) approximately paralleled the volume of scientific publications generated by each of Spain's 17 autonomous regions. The cocitation study showed that An. Med. Interna ranked somewhere in the middle of the group' of 38 Spanish medical journals considered representative of research being done in Spain. PMID:9376477

  19. Quantitative trait analysis in sequencing studies under trait-dependent sampling.

    PubMed

    Lin, Dan-Yu; Zeng, Donglin; Tang, Zheng-Zheng

    2013-07-23

    It is not economically feasible to sequence all study subjects in a large cohort. A cost-effective strategy is to sequence only the subjects with the extreme values of a quantitative trait. In the National Heart, Lung, and Blood Institute Exome Sequencing Project, subjects with the highest or lowest values of body mass index, LDL, or blood pressure were selected for whole-exome sequencing. Failure to account for such trait-dependent sampling can cause severe inflation of type I error and substantial loss of power in quantitative trait analysis, especially when combining results from multiple studies with different selection criteria. We present valid and efficient statistical methods for association analysis of sequencing data under trait-dependent sampling. We pay special attention to gene-based analysis of rare variants. Our methods can be used to perform quantitative trait analysis not only for the trait that is used to select subjects for sequencing but for any other traits that are measured. For a particular trait of interest, our approach properly combines the association results from all studies with measurements of that trait. This meta-analysis is substantially more powerful than the analysis of any single study. By contrast, meta-analysis of standard linear regression results (ignoring trait-dependent sampling) can be less powerful than the analysis of a single study. The advantages of the proposed methods are demonstrated through simulation studies and the National Heart, Lung, and Blood Institute Exome Sequencing Project data. The methods are applicable to other types of genetic association studies and nongenetic studies. PMID:23847208

  20. Quantitative three-dimensional photoacoustic tomography of the finger joints: an in vivo study

    NASA Astrophysics Data System (ADS)

    Sun, Yao; Sobel, Eric; Jiang, Huabei

    2009-11-01

    We present for the first time in vivo full three-dimensional (3-D) photoacoustic tomography (PAT) of the distal interphalangeal joint in a human subject. Both absorbed energy density and absorption coefficient images of the joint are quantitatively obtained using our finite-element-based photoacoustic image reconstruction algorithm coupled with the photon diffusion equation. The results show that major anatomical features in the joint along with the side arteries can be imaged with a 1-MHz transducer in a spherical scanning geometry. In addition, the cartilages associated with the joint can be quantitatively differentiated from the phalanx. This in vivo study suggests that the 3-D PAT method described has the potential to be used for early diagnosis of joint diseases such as osteoarthritis and rheumatoid arthritis.

  1. Quantitative comparison between type Ia supernova spectra at low and high redshifts: a case study

    NASA Astrophysics Data System (ADS)

    Garavini, G.; Folatelli, G.; Nobili, S.; Aldering, G.; Amanullah, R.; Antilogus, P.; Astier, P.; Blanc, G.; Bronder, T.; Burns, M. S.; Conley, A.; Deustua, S. E.; Doi, M.; Fabbro, S.; Fadeyev, V.; Gibbons, R.; Goldhaber, G.; Goobar, A.; Groom, D. E.; Hook, I.; Howell, D. A.; Kashikawa, N.; Kim, A. G.; Kowalski, M.; Kuznetsova, N.; Lee, B. C.; Lidman, C.; Mendez, J.; Morokuma, T.; Motohara, K.; Nugent, P. E.; Pain, R.; Perlmutter, S.; Quimby, R.; Raux, J.; Regnault, N.; Ruiz-Lapuente, P.; Sainton, G.; Schahmaneche, K.; Smith, E.; Spadafora, A. L.; Stanishev, V.; Thomas, R. C.; Walton, N. A.; Wang, L.; Wood-Vasey, W. M.; Yasuda, N.

    2007-08-01

    We develop a method to measure the strength of the absorption features in type Ia supernova (SN Ia) spectra and use it to make a quantitative comparisons between the spectra of type Ia supernovae at low and high redshifts. In this case study, we apply the method to 12 high-redshift (0.212 ≤ z ≤ 0.912) SNe Ia observed by the Supernova Cosmology Project. Through measurements of the strengths of these features and of the blueshift of the absorption minimum in Ca ii H&K, we show that the spectra of the high-redshift SNe Ia are quantitatively similar to spectra of nearby SNe Ia (z < 0.15). One supernova in our high redshift sample, SN 2002fd at z = 0.279, is found to have spectral characteristics that are associated with peculiar SN 1991T/SN 1999aa-like supernovae.

  2. Quantitative comparison between Type Ia supernova spectra at low and high redshifts: A case study

    SciTech Connect

    Supernova Cosmology Project; Nugent, Peter E; Garavini, G.; Folatelli, G.; Nobili, S.; Aldering, G.; Amanullah, R.; Antilogus, P.; Astier, P.; Blanc, G.; Bronder, J.; Burns, M.S.; Conley, A.; Deustua, S. E.; Doi, M.; Fabbro, S.; Fadeyev, V.; Gibbons, R.; Goldhaber, G.; Goobar, A.; Groom, D. E.; Hook, I.; Howell, D. A.; Kashikawa, N.; Kim, A. G.; Kowalski, M.; Kuznetsova, N.; Lee, B. C.; Lidman, C.; Mendez, J.; Morokuma, T.; Motohara, K.; Nugent, P. E.; Pain, R.; Perlmutter, S.; Quimby, R.; Raux, J.; Regnault, N.; Ruiz-Lapuente, P.; Sainton, G.; Schahmaneche, K.; Smith, E.; Spadafora, A. L.; Stanishev, V.; Thomas, R. C.; Walton, N. A.; Wang, L.; Wood-Vasey, W. M.; Yasuda, N.

    2008-03-24

    We develop a method to measure the strength of the absorption features in type Ia supernova (SN Ia) spectra and use it to make a quantitative comparisons between the spectra of type Ia supernovae at low and high redshifts. In this case study, we apply the method to 12 high-redshift (0.212 = z = 0.912) SNe Ia observed by the Supernova Cosmology Project. Through measurements of the strengths of these features and of the blueshift of theabsorption minimum in Ca ii H&K, we show that the spectra of the high-redshift SNe Ia are quantitatively similar to spectra of nearby SNe Ia (z< 0.15). One supernova in our high redshift sample, SN 2002fd at z = 0.279, is found to have spectral characteristics that are associated with peculiar SN 1991T/SN 1999aa-like supernovae.

  3. Using quantitative risk information in decisions about statins: a qualitative study in a community setting

    PubMed Central

    Polak, Louisa; Green, Judith

    2015-01-01

    Background A large literature informs guidance for GPs about communicating quantitative risk information so as to facilitate shared decision making. However, relatively little has been written about how patients utilise such information in practice. Aim To understand the role of quantitative risk information in patients’ accounts of decisions about taking statins. Design and setting This was a qualitative study, with participants recruited and interviewed in community settings. Method Semi-structured interviews were conducted with 34 participants aged >50 years, all of whom had been offered statins. Data were analysed thematically, using elements of the constant comparative method. Results Interviewees drew frequently on numerical test results to explain their decisions about preventive medication. In contrast, they seldom mentioned quantitative risk information, and never offered it as a rationale for action. Test results were spoken of as objects of concern despite an often-explicit absence of understanding, so lack of understanding seems unlikely to explain the non-use of risk estimates. Preventive medication was seen as ‘necessary’ either to treat test results, or because of personalised, unequivocal advice from a doctor. Conclusion This study’s findings call into question the assumption that people will heed and use numerical risk information once they understand it; these data highlight the need to consider the ways in which different kinds of knowledge are used in practice in everyday contexts. There was little evidence from this study that understanding probabilistic risk information was a necessary or valued condition for making decisions about statin use. PMID:25824187

  4. Bibliometric assessment of cancer research in Puerto Rico, 1903–2005

    PubMed Central

    Ortiz, Ana P.; Calo, William A.; Suárez-Balseiro, Carlos; Maura-Sardo, Mariano; Suárez, Erick

    2010-01-01

    Objective The analysis of scientific production in Puerto Rico is largely unexplored. The main aim of this study is to present the characteristics and trends of cancer publications in Puerto Rico’s biomedical journals and their relationship with the island’s cancer mortality. Methods A PubMed and a hard-copy search were performed to retrieve cancer-related articles published in the Puerto Rico Health Sciences Journal and the Boletín de la Asociación Médica de Puerto Rico from 1903 to 2005. Bibliometric indicators studied included the number of authors and references by article, first author’s institutional affiliation and country, document type, and language. The study type and tumor classification were also recorded. Cancer proportional mortality (M%) in Puerto Rico and the proportion of cancer-related articles (P%) published were also evaluated. The annual percent change (APC) was estimated to assess trends. Results A total of 369 articles were retrieved. The institutions with the majority of publications were universities (39.6%), English was the predominant publication language (72.1%), and the principal document type was original papers (69.6%). Epidemiologic studies were the dominant study type (62.1%), and the most studied cancers were digestive (15.4%) and gynecologic (9.6%). Although the P% has increased since 1913 (APC = 1.2%), the M% increased at a faster pace (APC = 2.7%). Conclusions Although a growth in the number of cancer publications is observed in these journals, it does not parallel the increase in proportional mortality. A better understanding of the cancer publications in Puerto Rico is essential to establish priorities, define future areas of research, and develop cancer control strategies. PMID:19531324

  5. Experimental study of the quantitative precision for valve-based comprehensive two-dimensional gas chromatography.

    PubMed

    Siegler, W Christopher; Fitz, Brian D; Hoggard, Jamin C; Synovec, Robert E

    2011-07-01

    For complex sample analysis, there is a need for multidimensional chromatographic instrumentation to be able to separate more compounds, often in shorter time frames. This has led to the development of comprehensive two-dimensional chromatographic instrumentation, such as comprehensive two-dimensional gas chromatography (GC × GC). Lately, much of the focus in this field has been on decreasing peak widths and, therefore, increasing peak capacity and peak capacity production. All of these advancements make it possible to analyze more compounds in a shorter amount of time, but the data still need to remain quantitative to address the needs of most applications. In this report, the relationship among the modulation ratio (M(R)), peak sampling phase (φ), retention time variation (Δt(R)), and how these parameters relate to quantitative analysis precision via the relative standard deviation (RSD) was studied experimentally using a valve-based GC × GC instrument. A wide range of the number of modulations across the first dimension peak width, that is, a M(R) range from ~1 to 10, was examined through maintaining an average first dimension peak width at the base, (1)w(b) of ~3 s and varying the second dimension separation run time from 300 to 2900 ms. An average RSD of 2.1% was experimentally observed at an average M(R) of 2, with a corresponding peak capacity production of ~1200 peaks/min possible. Below this M(R) the RSD quickly increased. In a long-term study of the quantitative precision at a M(R) of 2.5, using 126 replicate injections of a test mixture spanning ~35 h, the RSD averaged 3.0%. The findings have significant implications for optimizing peak capacity production by allowing the use of the longest second dimension run time, while maintaining quantitative precision. PMID:21627311

  6. Evaluation of chemotherapy response in ovarian cancer treatment using quantitative CT image biomarkers: a preliminary study

    NASA Astrophysics Data System (ADS)

    Qiu, Yuchen; Tan, Maxine; McMeekin, Scott; Thai, Theresa; Moore, Kathleen; Ding, Kai; Liu, Hong; Zheng, Bin

    2015-03-01

    The purpose of this study is to identify and apply quantitative image biomarkers for early prediction of the tumor response to the chemotherapy among the ovarian cancer patients participated in the clinical trials of testing new drugs. In the experiment, we retrospectively selected 30 cases from the patients who participated in Phase I clinical trials of new drug or drug agents for ovarian cancer treatment. Each case is composed of two sets of CT images acquired pre- and post-treatment (4-6 weeks after starting treatment). A computer-aided detection (CAD) scheme was developed to extract and analyze the quantitative image features of the metastatic tumors previously tracked by the radiologists using the standard Response Evaluation Criteria in Solid Tumors (RECIST) guideline. The CAD scheme first segmented 3-D tumor volumes from the background using a hybrid tumor segmentation scheme. Then, for each segmented tumor, CAD computed three quantitative image features including the change of tumor volume, tumor CT number (density) and density variance. The feature changes were calculated between the matched tumors tracked on the CT images acquired pre- and post-treatments. Finally, CAD predicted patient's 6-month progression-free survival (PFS) using a decision-tree based classifier. The performance of the CAD scheme was compared with the RECIST category. The result shows that the CAD scheme achieved a prediction accuracy of 76.7% (23/30 cases) with a Kappa coefficient of 0.493, which is significantly higher than the performance of RECIST prediction with a prediction accuracy and Kappa coefficient of 60% (17/30) and 0.062, respectively. This study demonstrated the feasibility of analyzing quantitative image features to improve the early predicting accuracy of the tumor response to the new testing drugs or therapeutic methods for the ovarian cancer patients.

  7. Genome-Wide Pathway Association Studies of Multiple Correlated Quantitative Phenotypes Using Principle Component Analyses

    PubMed Central

    Zhang, Feng; Guo, Xiong; Wu, Shixun; Han, Jing; Liu, Yongjun; Shen, Hui; Deng, Hong-Wen

    2012-01-01

    Genome-wide pathway association studies provide novel insight into the biological mechanism underlying complex diseases. Current pathway association studies primarily focus on single important disease phenotype, which is sometimes insufficient to characterize the clinical manifestations of complex diseases. We present a multi-phenotypes pathway association study(MPPAS) approach using principle component analysis(PCA). In our approach, PCA is first applied to multiple correlated quantitative phenotypes for extracting a set of orthogonal phenotypic components. The extracted phenotypic components are then used for pathway association analysis instead of original quantitative phenotypes. Four statistics were proposed for PCA-based MPPAS in this study. Simulations using the real data from the HapMap project were conducted to evaluate the power and type I error rates of PCA-based MPPAS under various scenarios considering sample sizes, additive and interactive genetic effects. A real genome-wide association study data set of bone mineral density (BMD) at hip and spine were also analyzed by PCA-based MPPAS. Simulation studies illustrated the performance of PCA-based MPPAS for identifying the causal pathways underlying complex diseases. Genome-wide MPPAS of BMD detected associations between BMD and KENNY_CTNNB1_TARGETS_UP as well as LONGEVITYPATHWAY pathways in this study. We aim to provide a applicable MPPAS approach, which may help to gain deep understanding the potential biological mechanism of association results for complex diseases. PMID:23285279

  8. Confocal reflectance quantitative phase microscopy system for cell biology studies (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Singh, Vijay Raj; So, Peter T. C.

    2016-03-01

    Quantitative phase microscopy (QPM), used to measure the refractive index, provides the optical path delay measurement at each point of the specimen under study and becomes an active field in biological science. In this work we present development of confocal reflection phase microscopy system to provide depth resolved quantitative phase information for investigation of intracellular structures and other biological specimen. The system hardware development is mainly divided into two major parts. First, creates a pinhole array for parallel confocal imaging of specimen at multiple locations simultaneously. Here a digital micro mirror device (DMD) is used to generate pinhole array by turning on a subset micro-mirrors arranged on a grid. Second is the detection of phase information of confocal imaging foci by using a common path interferometer. With this novel approach, it is possible to measure the nuclei membrane fluctuations and distinguish them from the plasma membrane fluctuations. Further, depth resolved quantitative phase can be correlated to the intracellular contents and 3D map of refractive index measurements.

  9. Application of multicriteria decision analysis in health care: a systematic review and bibliometric analysis

    PubMed Central

    Adunlin, Georges; Diaby, Vakaramoko; Xiao, Hong

    2015-01-01

    Background The use of Multi-Criteria Decision Analysis (MCDA) in health care has become common. However, the literature lacks systematic review trend analysis on the application of MCDA in health care. Aim To systematically identify applications of MCDA to the areas of health care, and to report on publication trends. Methods English language studies published from January 1, 1980 until October 1, 2013 were included. Electronic databases searches were supplemented by searching conference proceedings and relevant journals. Studies considered for inclusion were those using MCDA techniques within the areas of health care, and involving the participation of decision makers. A bibliometric analysis was undertaken to present the publication trends. Results A total of 66 citations met the inclusion criteria. An increase in publication trend occurred in the years 1990, 1997, 1999, 2005, 2008, and 2012. For the remaining years, the publication trend was either steady or declining. The trend shows that the number of publications reached its highest peak in 2012 (n = 9). Medical Decision Making was the dominant with the highest number published papers (n = 7). The majority of the studies were conducted in the US (n = 29). Medical Decision Making journal published the highest number of articles (n = 7). Analytic Hierarchy Process (n = 33) was the most used MCDA technique. Cancer was the most researched disease topic (n = 12). The most covered area of application was diagnosis and treatment (n = 26). Conclusion The review shows that MCDA has been applied to a broad range of areas in the health care, with the use of a variety of methodological approaches. Further research is needed to develop practice guidelines for the appropriate application and reporting of MCDA methods. PMID:25327341

  10. A Method to Prioritize Quantitative Traits and Individuals for Sequencing in Family-Based Studies

    PubMed Central

    Shah, Kaanan P.; Douglas, Julie A.

    2013-01-01

    Owing to recent advances in DNA sequencing, it is now technically feasible to evaluate the contribution of rare variation to complex traits and diseases. However, it is still cost prohibitive to sequence the whole genome (or exome) of all individuals in each study. For quantitative traits, one strategy to reduce cost is to sequence individuals in the tails of the trait distribution. However, the next challenge becomes how to prioritize traits and individuals for sequencing since individuals are often characterized for dozens of medically relevant traits. In this article, we describe a new method, the Rare Variant Kinship Test (RVKT), which leverages relationship information in family-based studies to identify quantitative traits that are likely influenced by rare variants. Conditional on nuclear families and extended pedigrees, we evaluate the power of the RVKT via simulation. Not unexpectedly, the power of our method depends strongly on effect size, and to a lesser extent, on the frequency of the rare variant and the number and type of relationships in the sample. As an illustration, we also apply our method to data from two genetic studies in the Old Order Amish, a founder population with extensive genealogical records. Remarkably, we implicate the presence of a rare variant that lowers fasting triglyceride levels in the Heredity and Phenotype Intervention (HAPI) Heart study (p = 0.044), consistent with the presence of a previously identified null mutation in the APOC3 gene that lowers fasting triglyceride levels in HAPI Heart study participants. PMID:23626830

  11. Studying the relationship between redox and cell growth using quantitative phase imaging (Conference Presentation)

    NASA Astrophysics Data System (ADS)

    Sridharan, Shamira; Leslie, Matthew T.; Bapst, Natalya; Smith, John; Gaskins, H. Rex; Popescu, Gabriel

    2016-03-01

    Quantitative phase imaging has been used in the past to study the dry mass of cells and study cell growth under various treatment conditions. However, the relationship between cellular redox and growth rates has not yet been studied in this context. This study employed the recombinant Glrx-roGFP2 redox biosensor targeted to the mitochondrial matrix or cytosolic compartments of A549 lung epithelial carcinoma cells. The Glrx-roGFP2s biosensor consists of a modified GFP protein containing internal cysteine residues sensitive to the local redox environment. The formation/dissolution of sulfide bridges contorts the internal chromophore, dictating corresponding changes in florescence emission that provide direct measures of the local redox potential. Combining 2-channel florescent imaging of the redox sensor with quantitative phase imaging allowed observation of redox homeostasis alongside measurements of cellular mass during full cycles of cellular division. The results indicate that mitochondrial redox showed a stronger inverse correlation with cell growth than cytoplasmic redox states; although redox changes are restricted to a 5% range. We are now studying the relationship between mitochondrial redox and cell growth in an isogenic series of breast cell lines built upon the MCF-10A genetic background that vary both in malignancy and metastatic potential.

  12. A new method for quantitating total lesion glucose metabolic changes in serial tumor FDG PET studies

    SciTech Connect

    Wu, H.M.; Hoh, C.K.; Huang, S.C.; Phelps, M.E.

    1994-05-01

    Accurate quantitative FDG PET studies have the potential for important applications in clinical oncology for monitoring therapy induced changes in tumor glycolytic rates. Due to a number of technical problems that complicate the use of quantitative PET tumor imaging, methods which can maximize the accuracy and precision of such measurements are advantageous. In this study, we developed and evaluated a method for reducing the errors caused by the conventional single plane, single ROI analysis in parametric images generated from pixel by pixel Patlak graphic analysis (PGA) in FDG PET studies of melanoma patients. We compared this new method to the conventional ROI method. The new processing method involves (1) generating the correlation coefficient (r) constrained Patlak parametric images from dynamic PET data; (2) summing up all the planes which cover the lesion; (3) defining a single ROI which covers the whole lesion in the summing image and determining the total lesion glucose metabolic index (K{sub T}, ml/min/lesion). Although only a single ROI was defined on the summing image, the glucose metabolic index obtained showed negligible difference (<1%) compared to those obtained from multiple ROIs on multiple planes of unconstrained parametric images. When the dynamic PET images were rotated and translated to simulate different patient positionings between scans at different times, the results obtained from the new method showed negligible difference (<2%). In summary, we present a simple but reliable method to quantitatively monitor the total lesion glucose metabolic changes during tumor growth. The method has several advantages over the conventional single ROI, single plane evaluation: (1) less sensitive to the ROI definition; (2) smaller intra- and inter-observer variations and (3) not requiring image registrations of serial scan data.

  13. The top 100 articles in the radiology of trauma: a bibliometric analysis.

    PubMed

    Dolan, Ryan Scott; Hanna, Tarek N; Warraich, Gohar Javed; Johnson, Jamlik-Omari; Khosa, Faisal

    2015-12-01

    The purpose of this study was to identify the 100 top-cited articles in the radiology of trauma, analyze the resulting database to understand factors resulting in highly cited works, and establish trends in trauma imaging. An initial database was created via a Web of Science (WOS) search of all scientific journals using the search terms "trauma" and either "radiology" or a diagnostic modality. Articles were ranked by citation count and screened by two attending radiologists plus a tiebreaker for appropriateness. The following information was collected from each article: WOS all database citations, year, journal, authors, department affiliation, study type and design, sample size, imaging modality, subspecialty, organ, and topic. Citations for the top 100 articles ranged from 82-252, and citations per year ranged from 2.6-37.2. A plurality of articles were published in the 1990s (n = 45) and 1980s (n = 31). Articles were published across 24 journals, most commonly Radiology (n = 31) and Journal of Trauma-Injury, Infection, and Critical Care (n = 28). Articles had an average of five authors and 35 % of first authors were affiliated with a department other than radiology. Forty-six articles had sample sizes of 100 or fewer. Computed tomography (CT) was the most common modality (n = 67), followed by magnetic resonance (MR; n = 22), and X-ray (XR; n = 11). Neuroradiology (n = 48) and abdominal radiology (n = 36) were the most common subspecialties. The 100 top-cited articles in the radiology of trauma are diverse. Subspecialty bibliometric analyses identify the most influential articles of a particular field, providing more implications to clinical radiologists, trainees, researchers, editors, and reviewers than radiology-wide lists. PMID:26377425

  14. Longitudinal trends in global obesity research and collaboration: a review using bibliometric metadata.

    PubMed

    Khan, A; Choudhury, N; Uddin, S; Hossain, L; Baur, L A

    2016-04-01

    The goal of this study was to understand research trends and collaboration patterns together with scholarly impact within the domain of global obesity research. We developed and analysed bibliographic affiliation data collected from 117,340 research articles indexed in Scopus database on the topic of obesity and published from 1993-2012. We found steady growth and an exponential increase of publication numbers. Research output in global obesity research roughly doubled each 5 years, with almost 80% of the publications and authors from the second decade (2003-2012). The highest publication output was from the USA - 42% of publications had at least one author from the USA. Many US institutions also ranked highly in terms of research output and collaboration. Fifteen of the top-20 institutions in terms of publication output were from the USA; however, several European and Japanese research institutions ranked more highly in terms of average citations per paper. The majority of obesity research and collaboration has been confined to developed countries although developing countries have showed higher growth in recent times, e.g. the publication ratio between 2003-2012 and 1993-2002 for developing regions was much higher than that of developed regions (9:1 vs. 4:1). We also identified around 42 broad disciplines from authors' affiliation data, and these showed strong collaboration between them. Overall, this study provides one of the most comprehensive longitudinal bibliometric analyses of obesity research. This should help in understanding research trends, spatial density, collaboration patterns and the complex multi-disciplinary nature of research in the obesity domain. PMID:26864566

  15. Quantitative Study Of Guide Field Effects on Hall Reconnection In A Laboratory Plasma

    SciTech Connect

    Tharp, T. D.; Yamada, M.; Ji, H.; Lawrence, E.; Dorfman, S.; Myers, C.; Yoo, J.

    2012-04-17

    The effect of guide field on magnetic reconnection is quantitatively studied by systematically varying an applied guide field in the Magnetic Reconnection Experiment (MRX). The quadrupole field, a signature of two-fluid reconnection at zero guide field, is significantly altered by a finite guide field. It is shown that the reconnection rate is significantly reduced with increasing guide field, and this dependence is explained by a combination of local and global physics: locally, the in-plane Hall currents are reduced, while globally guide field compression produces an increased pressure both within and downstream of the reconnection region. __________________________________________________

  16. SPECT Myocardial Blood Flow Quantitation Concludes Equivocal Myocardial Perfusion SPECT Studies to Increase Diagnostic Benefits.

    PubMed

    Chen, Lung-Ching; Lin, Chih-Yuan; Chen, Ing-Jou; Ku, Chi-Tai; Chen, Yen-Kung; Hsu, Bailing

    2016-01-01

    Recently, myocardial blood flow quantitation with dynamic SPECT/CT has been reported to enhance the detection of coronary artery disease in human. This advance has created important clinical applications to coronary artery disease diagnosis and management for areas where myocardial perfusion PET tracers are not available. We present 2 clinical cases that undergone a combined test of 1-day rest/dipyridamole-stress dynamic SPECT and ECG-gated myocardial perfusion SPECT scans using an integrated imaging protocol and demonstrate that flow parameters are capable to conclude equivocal myocardial perfusion SPECT studies, therefore increasing diagnostic benefits to add value in making clinical decisions. PMID:26053731

  17. Application of multispectral imaging in quantitative immunohistochemistry study of breast cancer: a comparative study.

    PubMed

    Liu, Wen-Lou; Wang, Lin-Wei; Chen, Jia-Mei; Yuan, Jing-Ping; Xiang, Qing-Ming; Yang, Gui-Fang; Qu, Ai-Ping; Liu, Juan; Li, Yan

    2016-04-01

    Multispectral imaging (MSI) based on imaging and spectroscopy, as relatively novel to the field of histopathology, has been used in biomedical multidisciplinary researches. We analyzed and compared the utility of multispectral (MS) versus conventional red-green-blue (RGB) images for immunohistochemistry (IHC) staining to explore the advantages of MSI in clinical-pathological diagnosis. The MS images acquired of IHC-stained membranous marker human epidermal growth factor receptor 2 (HER2), cytoplasmic marker cytokeratin5/6 (CK5/6), and nuclear marker estrogen receptor (ER) have higher resolution, stronger contrast, and more accurate segmentation than the RGB images. The total signal optical density (OD) values for each biomarker were higher in MS images than in RGB images (all P < 0.05). Moreover, receiver operator characteristic (ROC) analysis revealed that a greater area under the curve (AUC), higher sensitivity, and specificity in evaluation of HER2 gene were achieved by MS images (AUC = 0.91, 89.1 %, 83.2 %) than RGB images (AUC = 0.87, 84.5, and 81.8 %). There was no significant difference between quantitative results of RGB images and clinico-pathological characteristics (P > 0.05). However, by quantifying MS images, the total signal OD values of HER2 positive expression were correlated with lymph node status and histological grades (P = 0.02 and 0.04). Additionally, the consistency test results indicated the inter-observer agreement was more robust in MS images for HER2 (inter-class correlation coefficient (ICC) = 0.95, r s = 0.94), CK5/6 (ICC = 0.90, r s = 0.88), and ER (ICC = 0.94, r s = 0.94) (all P < 0.001) than that in RGB images for HER2 (ICC = 0.91, r s = 0.89), CK5/6 (ICC = 0.85, r s = 0.84), and ER (ICC = 0.90, r s = 0.89) (all P < 0.001). Our results suggest that the application of MS images in quantitative IHC analysis could obtain higher accuracy, reliability, and more

  18. A Robust Distribution-Free Test for Genetic Association Studies of Quantitative Traits

    PubMed Central

    Kozlitina, Julia; Schucany, William R.

    2016-01-01

    In association studies of quantitative traits, the association of each genetic marker with the trait of interest is typically tested using the F-test assuming an additive genetic model. In practice, the true model is rarely known, and specifying an incorrect model can lead to a loss of power. For case-control studies, the maximum of test statistics optimal for additive, dominant, and recessive models has been shown to be robust to model mis-specification. The approach has later been extended to quantitative traits. However, the existing procedures assume that the trait is normally distributed and may not maintain correct type-I error rates and can also have reduced power when the assumption of normality is violated. Here, we introduce a maximum (MAX3) test that is based on ranks and is therefore distribution-free. We examine the behavior of the proposed method using a Monte-Carlo simulation with both normal and non-normal data and compare the results to the usual parametric procedures and other nonparametric alternatives. We show that the rank-based maximum test has favorable properties relative to other tests, especially in the case of symmetric distributions with heavy tails. We illustrate the method with data from a real association study of symmetric dimethylarginine (SDMA). PMID:26426896

  19. Quantitative Susceptibility Mapping Indicates a Disturbed Brain Iron Homeostasis in Neuromyelitis Optica - A Pilot Study.

    PubMed

    Doring, Thomas Martin; Granado, Vanessa; Rueda, Fernanda; Deistung, Andreas; Reichenbach, Juergen R; Tukamoto, Gustavo; Gasparetto, Emerson Leandro; Schweser, Ferdinand

    2016-01-01

    Dysregulation of brain iron homeostasis is a hallmark of many neurodegenerative diseases and can be associated with oxidative stress. The objective of this study was to investigate brain iron in patients with Neuromyelitis Optica (NMO) using quantitative susceptibility mapping (QSM), a quantitative iron-sensitive MRI technique. 12 clinically confirmed NMO patients (6 female and 6 male; age 35.4y±14.2y) and 12 age- and sex-matched healthy controls (7 female and 5 male; age 33.9±11.3y) underwent MRI of the brain at 3 Tesla. Quantitative maps of the effective transverse relaxation rate (R2*) and magnetic susceptibility were calculated and a blinded ROI-based group comparison analysis was performed. Normality of the data and differences between patients and controls were tested by Kolmogorov-Smirnov and t-test, respectively. Correlation with age was studied using Spearman's rank correlation and an ANCOVA-like analysis. Magnetic susceptibility values were decreased in the red nucleus (p<0.01; d>0.95; between -15 and -22 ppb depending on reference region) with a trend toward increasing differences with age. R2* revealed significantly decreased relaxation in the optic radiations of five of the 12 patients (p<0.0001; -3.136±0.567 s-1). Decreased relaxation in the optic radiation is indicative for demyelination, which is in line with previous findings. Decreased magnetic susceptibility in the red nucleus is indicative for a lower brain iron concentration, a chemical redistribution of iron into less magnetic forms, or both. Further investigations are necessary to elucidate the pathological cause or consequence of this finding. PMID:27171423

  20. Neurobiological origin of spurious brain morphological changes: A quantitative MRI study

    PubMed Central

    Lorio, Sara; Kherif, Ferath; Ruef, Anne; Melie‐Garcia, Lester; Frackowiak, Richard; Ashburner, John; Helms, Gunther

    2016-01-01

    Abstract The high gray‐white matter contrast and spatial resolution provided by T1‐weighted magnetic resonance imaging (MRI) has made it a widely used imaging protocol for computational anatomy studies of the brain. While the image intensity in T1‐weighted images is predominantly driven by T1, other MRI parameters affect the image contrast, and hence brain morphological measures derived from the data. Because MRI parameters are correlates of different histological properties of brain tissue, this mixed contribution hampers the neurobiological interpretation of morphometry findings, an issue which remains largely ignored in the community. We acquired quantitative maps of the MRI parameters that determine signal intensities in T1‐weighted images (R 1 (=1/T1), R 2*, and PD) in a large cohort of healthy subjects (n = 120, aged 18–87 years). Synthetic T1‐weighted images were calculated from these quantitative maps and used to extract morphometry features—gray matter volume and cortical thickness. We observed significant variations in morphometry measures obtained from synthetic images derived from different subsets of MRI parameters. We also detected a modulation of these variations by age. Our findings highlight the impact of microstructural properties of brain tissue—myelination, iron, and water content—on automated measures of brain morphology and show that microstructural tissue changes might lead to the detection of spurious morphological changes in computational anatomy studies. They motivate a review of previous morphological results obtained from standard anatomical MRI images and highlight the value of quantitative MRI data for the inference of microscopic tissue changes in the healthy and diseased brain. Hum Brain Mapp 37:1801–1815, 2016. © 2016 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:26876452

  1. Quantitative Susceptibility Mapping Indicates a Disturbed Brain Iron Homeostasis in Neuromyelitis Optica – A Pilot Study

    PubMed Central

    Granado, Vanessa; Rueda, Fernanda; Deistung, Andreas; Reichenbach, Juergen R.; Tukamoto, Gustavo; Gasparetto, Emerson Leandro; Schweser, Ferdinand

    2016-01-01

    Dysregulation of brain iron homeostasis is a hallmark of many neurodegenerative diseases and can be associated with oxidative stress. The objective of this study was to investigate brain iron in patients with Neuromyelitis Optica (NMO) using quantitative susceptibility mapping (QSM), a quantitative iron-sensitive MRI technique. 12 clinically confirmed NMO patients (6 female and 6 male; age 35.4y±14.2y) and 12 age- and sex-matched healthy controls (7 female and 5 male; age 33.9±11.3y) underwent MRI of the brain at 3 Tesla. Quantitative maps of the effective transverse relaxation rate (R2*) and magnetic susceptibility were calculated and a blinded ROI-based group comparison analysis was performed. Normality of the data and differences between patients and controls were tested by Kolmogorov-Smirnov and t-test, respectively. Correlation with age was studied using Spearman’s rank correlation and an ANCOVA-like analysis. Magnetic susceptibility values were decreased in the red nucleus (p<0.01; d>0.95; between -15 and -22 ppb depending on reference region) with a trend toward increasing differences with age. R2* revealed significantly decreased relaxation in the optic radiations of five of the 12 patients (p<0.0001; -3.136±0.567 s-1). Decreased relaxation in the optic radiation is indicative for demyelination, which is in line with previous findings. Decreased magnetic susceptibility in the red nucleus is indicative for a lower brain iron concentration, a chemical redistribution of iron into less magnetic forms, or both. Further investigations are necessary to elucidate the pathological cause or consequence of this finding. PMID:27171423

  2. Neurobiological origin of spurious brain morphological changes: A quantitative MRI study.

    PubMed

    Lorio, Sara; Kherif, Ferath; Ruef, Anne; Melie-Garcia, Lester; Frackowiak, Richard; Ashburner, John; Helms, Gunther; Lutti, Antoine; Draganski, Bodgan

    2016-05-01

    The high gray-white matter contrast and spatial resolution provided by T1-weighted magnetic resonance imaging (MRI) has made it a widely used imaging protocol for computational anatomy studies of the brain. While the image intensity in T1-weighted images is predominantly driven by T1, other MRI parameters affect the image contrast, and hence brain morphological measures derived from the data. Because MRI parameters are correlates of different histological properties of brain tissue, this mixed contribution hampers the neurobiological interpretation of morphometry findings, an issue which remains largely ignored in the community. We acquired quantitative maps of the MRI parameters that determine signal intensities in T1-weighted images (R1 (=1/T1), R2 *, and PD) in a large cohort of healthy subjects (n = 120, aged 18-87 years). Synthetic T1-weighted images were calculated from these quantitative maps and used to extract morphometry features-gray matter volume and cortical thickness. We observed significant variations in morphometry measures obtained from synthetic images derived from different subsets of MRI parameters. We also detected a modulation of these variations by age. Our findings highlight the impact of microstructural properties of brain tissue-myelination, iron, and water content-on automated measures of brain morphology and show that microstructural tissue changes might lead to the detection of spurious morphological changes in computational anatomy studies. They motivate a review of previous morphological results obtained from standard anatomical MRI images and highlight the value of quantitative MRI data for the inference of microscopic tissue changes in the healthy and diseased brain. Hum Brain Mapp 37:1801-1815, 2016. © 2016 The Authors. Human Brain Mapping Published by Wiley Periodicals, Inc. PMID:26876452

  3. The renal quantitative scintillation camera study for determination of renal function

    SciTech Connect

    Thompson, I.M. Jr.; Boineau, F.G.; Evans, B.B.; Schlegel, J.U.

    1983-03-01

    The renal quantitative scintillation camera study assesses glomerular filtration rate and effective renal plasma flow based upon renal uptake of 99mtechnetium-iron ascorbate and 131iodine-hippuran, respectively. The method was compared to inulin, para-aminohippuric acid and creatinine clearance studies in 7 normal subjects and 9 patients with various degrees of reduced renal function. The reproducibility of the technique was determined in 15 randomly selected pediatric patients. The values of glomerular filtration rate and effective renal plasma flow were not significantly different from those of inulin and para-aminohippuric acid studies. The reproducibility of the technique was comparable to that of inulin and para-aminohippuric acid studies. Patient acceptance of the technique is excellent and the cost is minimal. Renal morphology and excretory dynamics also are demonstrated. The technique is advocated as a clinical measure of renal function.

  4. Quantitative study of temperature-dependent order in thin films of cylindrical morphology block copolymer

    NASA Astrophysics Data System (ADS)

    Mishra, Vindhya; Kramer, Edward

    2010-03-01

    Disordering and defect generation in block copolymer systems at high temperatures is of significance to get a better understanding of the physics governing these systems, which can also direct efforts to minimize them. We have studied the smectic-nematic-isotropic transition in confined monolayers and bilayers of cylindrical morphology poly (styrene-b-2vinyl pyridine) diblock copolymer. Previous studies of melting phenomena in block copolymer thin films have relied on quantitative AFM studies alone. We have supplemented AFM studies with grazing incidence small angle X-ray diffraction lineshape analysis to quantify the decay of translational and orientational order with increasing temperature. The results have been interpreted in the context of the Toner-Nelson theory of melting for layered systems.

  5. Balkanized Research in Ecological Engineering Revealed by a Bibliometric Analysis of Earthworms and Ecosystem Services

    NASA Astrophysics Data System (ADS)

    Blouin, Manuel; Sery, Nicolas; Cluzeau, Daniel; Brun, Jean-Jacques; Bédécarrats, Alain

    2013-08-01

    Energy crisis, climate changes, and biodiversity losses have reinforced the drive for more ecologically-based approaches for environmental management. Such approaches are characterized by the use of organisms rather than energy-consuming technologies. Although earthworms are believed to be potentially useful organisms for managing ecosystem services, there is actually no quantification of such a trend in literature. This bibliometric analysis aimed to measure the evolution of the association of "earthworms" and other terms such as ecosystem services (primary production, nutrient cycling, carbon sequestration, soil structure, and pollution remediation), "ecological engineering" or "biodiversity," to assess their convergence or divergence through time. In this aim, we calculated the similarity index, an indicator of the paradigmatic proximity defined in applied epistemology, for each year between 1900 and 2009. We documented the scientific fields and the geographical origins of the studies, as well as the land uses, and compare these characteristics with a 25 years old review on earthworm management. The association of earthworm related keywords with ecosystem services related keywords was increasing with time, reflecting the growing interest in earthworm use in biodiversity and ecosystem services management. Conversely, no significant increase in the association between earthworms and disciplines such as ecological engineering or restoration ecology was observed. This demonstrated that general ecologically-based approaches have yet to emerge and that there is little exchange of knowledge, methods or concepts among balkanized application realms. Nevertheless, there is a strong need for crossing the frontiers between fields of application and for developing an umbrella discipline to provide a framework for the use of organisms to manage ecosystem services.

  6. Balkanized research in ecological engineering revealed by a bibliometric analysis of earthworms and ecosystem services.

    PubMed

    Blouin, Manuel; Sery, Nicolas; Cluzeau, Daniel; Brun, Jean-Jacques; Bédécarrats, Alain

    2013-08-01

    Energy crisis, climate changes, and biodiversity losses have reinforced the drive for more ecologically-based approaches for environmental management. Such approaches are characterized by the use of organisms rather than energy-consuming technologies. Although earthworms are believed to be potentially useful organisms for managing ecosystem services, there is actually no quantification of such a trend in literature. This bibliometric analysis aimed to measure the evolution of the association of "earthworms" and other terms such as ecosystem services (primary production, nutrient cycling, carbon sequestration, soil structure, and pollution remediation), "ecological engineering" or "biodiversity," to assess their convergence or divergence through time. In this aim, we calculated the similarity index, an indicator of the paradigmatic proximity defined in applied epistemology, for each year between 1900 and 2009. We documented the scientific fields and the geographical origins of the studies, as well as the land uses, and compare these characteristics with a 25 years old review on earthworm management. The association of earthworm related keywords with ecosystem services related keywords was increasing with time, reflecting the growing interest in earthworm use in biodiversity and ecosystem services management. Conversely, no significant increase in the association between earthworms and disciplines such as ecological engineering or restoration ecology was observed. This demonstrated that general ecologically-based approaches have yet to emerge and that there is little exchange of knowledge, methods or concepts among balkanized application realms. Nevertheless, there is a strong need for crossing the frontiers between fields of application and for developing an umbrella discipline to provide a framework for the use of organisms to manage ecosystem services. PMID:23716007

  7. Bio-medicolegal scientific research in Europe: a comprehensive bibliometric overview.

    PubMed

    Ferrara, Santo Davide; Bajanowski, Thomas; Cecchi, Rossana; Boscolo-Berto, Rafael; Viel, Guido

    2011-05-01

    In times of globalisation, the future of bio-medicolegal sciences in Europe depends on the scientific community's ability to develop new strategies for research, to introduce new and generally accepted standards, to develop new analytical methods, all in order to draw up inter-site, multidisciplinary and interdisciplinary long-term research projects, eligible for European Union (EU) funding. To analyse the scientific output and to identify the topics of greatest interest and appeal in these sciences, an innovative method has been developed to select and analyse publications. This method has been applied to analyse a total of 21,176 records from PubMed out of which 5,826 papers were suitable for further analysis because they were published in national and international journals in the time between January 1, 2005 and June 1, 2010 by European authors in the field of interest. In 69% of all manuscripts, authors presented results of systematic research (original articles); 84% of the papers were written in English language. The cumulative impact factor increased from 1,670 points in 2005 to 1,878 in 2009, and extrapolated 2,812 points in 2010. The most frequent topics were the description of new analytical methods in forensic toxicology (5.7% of all papers), the analysis of short tandem repeat systems (STR, 5.6%) as well as the analysis of injury mechanisms in forensic pathology and clinical forensic medicine (4.9%). If the impact factor related potential of different topics is calculated (ratio of frequency of papers and frequency of impact points achieved), SIDS research reaches 1.64 points, followed by studies on mtDNA (1.59) and the development of new analytical methods in forensic toxicology (1.49). The findings made in the present bibliometric analysis reveal a clear and interesting overall picture of the European scientific production and productivity and could be used to identify the most innovative research lines. PMID:21191611

  8. A bibliometric analysis of the 100 most influential papers on COPD

    PubMed Central

    Gu, Wenchao; Yuan, Yaping; Yang, Hua; Qi, Guangsheng; Jin, Xiaoyan; Yan, Jin

    2015-01-01

    Objective We aimed to identify the 100 top-cited articles published on chronic obstructive pulmonary disease (COPD) and to analyze their characteristics so as to provide information on the achievement and development in COPD research over the past decades. Methods and materials A comprehensive list of citation classics in COPD was generated by searching the Science Citation Index expanded database, using the keywords “COPD” or “chronic obstructive pulmonary disease” or “chronic obstructive pulmonary diseases”. The 100 top-cited research papers were retrieved by reading the abstract or full text if needed. All eligible articles were read for basic information, including country of origin, organizations, article type, journals, research field, and authors. Results The 100 top-cited articles on COPD were published between 1966 and 2010. The number of citations ranged from 254 to 2,164, with a mean of 450 citations for each article. These citation classics were from 32 countries, with 38 from the United States. The Imperial College London led the list of classics, with 16 papers. The 100 top-cited articles were distributed in 18 journals, with the American Journal of Respiratory, Critical Care Medicine, and Journal of the American Medical Association topping the list. Among the various fields, both respiratory system (63%) and general internal medicine (63%) were the most common fields of study for the 100 articles. Conclusion Our bibliometric analysis provides a historical perspective on the progress of scientific research on COPD. Articles originating from the United States and published in high-impact specialized respiratory journals are most likely to be cited in the field of COPD research. PMID:25848243

  9. A Bibliometric Analysis of the 100 Most-cited Articles in Rhinoplasty

    PubMed Central

    Iqbal, Fahad M.; Spence, John N.; Richard, Bruce

    2016-01-01

    Introduction: Citation analysis aims to quantify the importance and influence of a published article within its field. We performed a bibliometric analysis to determine the most highly cited articles within rhinoplasty and their impact on current practice. Methods: The 100 most-cited articles relating to rhinoplasty, between and inclusive of January 1864 to September 2015, were extracted from Web of Science in October 2015. Title, source journal, publication year, total citations, average citations/year, type of article, level of evidence, country of origin, main focus, use of outcome measures, incorporation into “Selected Readings in Plastic Surgery,” and funding status were recorded. Results: The total number of citations per article ranged from 61 to 276 (1.5–12.1 average citations per year). Surgical technique was the focus of 53% of articles, particularly those for reconstruction (75%). The United States produced 72% of articles compared with 8% from the United Kingdom. The top 100 articles were published within 20 journals; “Plastic and Reconstructive Surgeons” contributed the most articles (n = 57). None of the articles achieved level 1 or 2 of evidence (Oxford Centre for Evidence-Based Medicine levels of evidence, 2011), with most achieving level 4 evidence (n = 64). Case-series were the most popular methodology (n = 37). Few articles used validated outcome measures (n = 21). Twenty-nine percent were referenced in “selected readings.” Eighty-nine percent were unfunded studies. Conclusions: These top 100 articles are used in current teaching material and underpin surgical decision making. Developing and using validated objective assessment tools will benefit surgeons, patients, and the greater scientific community in objectively evaluating techniques with the most favorable results. PMID:27536499

  10. A Framework for Mixing Methods in Quantitative Measurement Development, Validation, and Revision: A Case Study

    ERIC Educational Resources Information Center

    Luyt, Russell

    2012-01-01

    A framework for quantitative measurement development, validation, and revision that incorporates both qualitative and quantitative methods is introduced. It extends and adapts Adcock and Collier's work, and thus, facilitates understanding of quantitative measurement development, validation, and revision as an integrated and cyclical set of…

  11. A quantitative Kirkpatrick Level 1 and 2 study of equipment specialist apprentice operations training

    NASA Astrophysics Data System (ADS)

    Hughes, Dirk D.

    The primary purpose of the quantitative experimental study is to compare employee-learning outcomes for a course of study that is offered in two formats: explicit and tacit instructor led and explicit e-learning operations training. A Kirkpatrick Level 2 course examination is used to establish a pretest knowledge baseline and to measure posttest learning outcomes for each instructional format. A secondary purpose is to compare responses of the two groups using a Kirkpatrick Level 1 customer satisfaction index survey. Several authors reported the United States electric utility industry would have an employee attrition issue during the 2010 through 2015 period. This is at the same time the industry will be experiencing an increased demand for electricity. There now is a demand for highly training powerplant operators. A review of literature yielded few studies comparing instructor led training and e-based training. Though the Electric Power Research Institute stated the two training modes would be acceptable instruction, the organization did not develop a quantifiable justified recommendation as to the training. Subjects participated in a basic operations course and decided to take either the instructor led or e-based training course. Results of the study concluded that both instructor led and e-based training provided significant learning to the participants. The Kirkpatrick Level 1 results indicated significantly better results for instructor led training. There was not a significant difference in the Kirkpatrick Level 2 results between the two training modalities. Recommendation for future research include conducting a quantitative studies including a Phillips Level 5 study and qualitative studies including a more detailed examination of the customer satisfaction survey (Kirkpatrick Level 1).

  12. A review of published quantitative experimental studies on factors affecting laboratory fume hood performance.

    PubMed

    Ahn, Kwangseog; Woskie, Susan; DiBerardinis, Louis; Ellenbecker, Michael

    2008-11-01

    This study attempted to identify the important factors that affect the performance of a laboratory fume hood and the relationship between the factors and hood performance under various conditions by analyzing and generalizing the results from other studies that quantitatively investigated fume hood performance. A literature search identified 43 studies that were published from 1966 to 2006. For each of those studies, information on the type of test methods used, the factors investigated, and the findings were recorded and summarized. Among the 43 quantitative experimental studies, 21 comparable studies were selected, and then a meta-analysis of the comparable studies was conducted. The exposure concentration variable from the resulting 617 independent test conditions was dichotomized into acceptable or unacceptable using the control level of 0.1 ppm tracer gas. Regression analysis using Cox proportional hazards models provided hood failure ratios for potential exposure determinants. The variables that were found to be statistically significant were the presence of a mannequin/human subject, the distance between a source and breathing zone, and the height of sash opening. In summary, performance of laboratory fume hoods was affected mainly by the presence of a mannequin/human subject, distance between a source and breathing zone, and height of sash opening. Presence of a mannequin/human subject in front of the hood adversely affects hood performance. Worker exposures to air contaminants can be greatly reduced by increasing the distance between the contaminant source and breathing zone and by reducing the height of sash opening. Many other factors can also affect hood performance. Checking face velocity by itself is unlikely to be sufficient in evaluating hood performance properly. An evaluation of the performance of a laboratory fume hood should be performed with a human subject or a mannequin in front of the hood and should address the effects of the activities

  13. A Quantitative Study on the Trachea of the Red Sokoto (Maradi) Goat (Capra hircus)

    PubMed Central

    Byanet, O.; Bosha, J. A.; Onoja, B. O.

    2014-01-01

    The trachea forms the part of the conducting system which transports air from the external environment to the lungs. The aim of this study was to provide quantitative dimensions of the trachea of Red Sokoto goat (Capra hircus). Quantitative analysis was conducted on nine tracheas from goats (ages were ranged between eight months and three years) without sex variation in this study. The results showed that tracheas were extended from the cricoid cartilage of larynx to the hilus of the lungs, where they were divided into the right and left bronchi. They were structurally composed of the cartilaginous rings that were incomplete dorsally but bridged by tracheal muscles at the ends of the tracheal cartilages. The mean length of the trachea from the first to the last ring was 257 ± 7.11 mm and the number of tracheal rings varied from 35 to 57, with a mean value of 49.33 ± 2.78. The left bronchial mean length (19.78 ± 2.66 mm) was significantly longer than the right (10.44 ± 1.79 mm). The cross-sectional area (CSA) was wider at the intrathoracic area (221.5 ± 0.2 mm2) than cervical area (176 ± 0.1 mm2). PMID:24616822

  14. Quantitative imaging of the human upper airway: instrument design and clinical studies

    NASA Astrophysics Data System (ADS)

    Leigh, M. S.; Armstrong, J. J.; Paduch, A.; Sampson, D. D.; Walsh, J. H.; Hillman, D. R.; Eastwood, P. R.

    2006-08-01

    Imaging of the human upper airway is widely used in medicine, in both clinical practice and research. Common imaging modalities include video endoscopy, X-ray CT, and MRI. However, no current modality is both quantitative and safe to use for extended periods of time. Such a capability would be particularly valuable for sleep research, which is inherently reliant on long observation sessions. We have developed an instrument capable of quantitative imaging of the human upper airway, based on endoscopic optical coherence tomography. There are no dose limits for optical techniques, and the minimally invasive imaging probe is safe for use in overnight studies. We report on the design of the instrument and its use in preliminary clinical studies, and we present results from a range of initial experiments. The experiments show that the instrument is capable of imaging during sleep, and that it can record dynamic changes in airway size and shape. This information is useful for research into sleep disorders, and potentially for clinical diagnosis and therapies.

  15. A relative quantitative assessment of myocardial perfusion by first-pass technique: animal study

    NASA Astrophysics Data System (ADS)

    Chen, Jun; Zhang, Zhang; Yu, Xuefang; Zhou, Kenneth J.

    2015-03-01

    The purpose of this study is to quantitatively assess the myocardial perfusion by first-pass technique in swine model. Numerous techniques based on the analysis of Computed Tomography (CT) Hounsfield Unit (HU) density have emerged. Although these methods proposed to be able to assess haemodynamically significant coronary artery stenosis, their limitations are noticed. There are still needs to develop some new techniques. Experiments were performed upon five (5) closed-chest swine. Balloon catheters were placed into the coronary artery to simulate different degrees of luminal stenosis. Myocardial Blood Flow (MBF) was measured using color microsphere technique. Fractional Flow Reserve (FFR) was measured using pressure wire. CT examinations were performed twice during First-pass phase under adenosine-stress condition. CT HU Density (HUDCT) and CT HU Density Ratio (HUDRCT) were calculated using the acquired CT images. Our study presents that HUDRCT shows a good (y=0.07245+0.09963x, r2=0.898) correlation with MBF and FFR. In receiver operating characteristic (ROC) curve analyses, HUDRCT provides excellent diagnostic performance for the detection of significant ischemia during adenosine-stress as defined by FFR indicated by the value of Area Under the Curve (AUC) of 0.927. HUDRCT has the potential to be developed as a useful indicator of quantitative assessment of myocardial perfusion.

  16. Marriage Patterns and Childbearing: Results From a Quantitative Study in North of Iran.

    PubMed

    Taghizadeh, Ziba; Behmanesh, Fereshteh; Ebadi, Abbas

    2016-03-01

    Social changes have rapidly removed arranged marriages and it seems the change in marriage pattern has played a role in childbearing. On the other hand, there is a great reduction in population in many countries which requires a comprehensive policy to manage the considerable drop in population. To achieve this goal, initially, the factors affecting fertility must be precisely identified. This study aims to examine the role of marriage patterns in childbearing. In this cross-sectional quantitative study, 880 married women 15-49 years old, living in the north of Iran were studied using a cluster sampling strategy. The results showed that there are no significant differences in reproductive behaviors of three patterns of marriage in Bobol city of Iran. It seems there is a convergence in childbearing due to the different patterns of marriage and Policymakers should pay attention to other determinants of reproductive behaviors in demographic planning. PMID:26493414

  17. Green initiative impact on stock prices: A quantitative study of the clean energy industry

    NASA Astrophysics Data System (ADS)

    Jurisich, John M.

    The purpose of this quantitative ex post facto research study was to explore the relationship between green initiative expense disclosures and stock prices of 46 NASDAQ listed Clean Edge Green Energy global companies from 2007 to 2010. The independent variables were sales and marketing, environmental, customer and supplier, community, and corporate governance practices that were correlated with the dependent variable in the study of stock prices. Expense disclosures were examined in an effort to measure the impact of green initiative programs and to expose the interrelationships between green initiative expense disclosures and fluctuations of stock prices. The data for the research was secondary data from existing annual reports. A statistically significant relationship was revealed between environmental practices and changes in stock prices. The study results also provided substantial evidence for leadership and managerial decision making to reduce or increase green initiative practices to maximize shareholder wealth of their respective organizations.

  18. Marriage Patterns and Childbearing: Results From a Quantitative Study in North of Iran

    PubMed Central

    Taghizadeh, Ziba; Behmanesh, Fereshteh; Ebadi, Abbas

    2016-01-01

    Social changes have rapidly removed arranged marriages and it seems the change in marriage pattern has played a role in childbearing. On the other hand, there is a great reduction in population in many countries which requires a comprehensive policy to manage the considerable drop in population. To achieve this goal, initially, the factors affecting fertility must be precisely identified. This study aims to examine the role of marriage patterns in childbearing. In this cross-sectional quantitative study, 880 married women 15-49 years old, living in the north of Iran were studied using a cluster sampling strategy. The results showed that there are no significant differences in reproductive behaviors of three patterns of marriage in Bobol city of Iran. It seems there is a convergence in childbearing due to the different patterns of marriage and Policymakers should pay attention to other determinants of reproductive behaviors in demographic planning. PMID:26493414

  19. Quantitative Study of Energization of Plasma Particles in the Magnetic Reconnection Layer of a Laboratory Plasma

    NASA Astrophysics Data System (ADS)

    Yamada, M.; Yoo, J.; Swanson, C.; Jara Almonte, J.; Ji, H.; Myers, C. E.; Chen, L.

    2013-12-01

    Quantitative study of the energization of plasma particles in the magnetic reconnection layer has been carried out by monitoring the behavior of electrons and ions in MRX (1, 2). The measured profiles of plasma parameters are quantitatively analyzed with symmetric as well as asymmetric upstream conditions in the context of the two-fluid reconnection physics (1) and compared with the recent numerical simulation results. The electron heating is observed to extend beyond the electron diffusion region and considered to be due to energization by magnetic instabilities of incoming electrons trapped in the magnetic mirror. This energization often occurs impulsively. Ions are accelerated by an electrostatic field across the separatrices to the plasma exhaust region of the reconnection layer and become thermalized through re-magnetization by the exiting magnetic fields. In this paper, the acceleration and heating of ions and electrons which extents much wider than the length scale of the ion skin depth, is addressed quantitatively for the first time in a laboratory reconnection layer. A total energy inventory is calculated based on analysis of the Poynting, enthalpy, flow energy, and heat flux in the measured diffusion layer (3). More than half of the incoming magnetic energy is converted to particle energy during collisionless reconnection. The results will bring a new insight into the conversion mechanism of magnetic energy to that of plasma particles during magnetic reconnection. (1) M. Yamada, R. Kulsrud, H. Ji, Rev. Mod. Phys. v.82, 602 (2010) (2) J. Yoo et al, Phys. Rev. Letts. 110, 215007 (2013) (3) J. Eastwood et al., PRL 110, 225001 (2013) Fig. 1. Measured in-plane ion flow vectors along with the measured 2-D profile of the in-plane plasma potential Φp in the half reconnection plane of MRX. The thin black lines are measured contours of poloidal flux ψp. While ions flow across the separatrices, they turn in-plane electric field Ein.

  20. Correlation Between the Severity of Diabetic Peripheral Polyneuropathy and Glycosylated Hemoglobin Levels: A Quantitative Study

    PubMed Central

    Lee, Won-Jae; Jang, Sol; Lee, Seung-Hwa

    2016-01-01

    Objective To investigate risk factors for diabetic peripheral polyneuropathy and their correlation with the quantified severity of nerve dysfunction in patients with diabetes mellitus (DM). Methods A total of 187 diabetic patients with clinically suspected polyneuropathy (PN) were subclassified into 2 groups according to electrodiagnostic testing: a DM-PN group of 153 diabetic patients without electrophysiological abnormality and a DM+PN group of 34 diabetic patients with polyneuropathy. For all patients, age, sex, height, weight, duration of DM, and plasma glycosylated hemoglobin (HbA1c) level were comparatively investigated. A composite score was introduced to quantitatively analyze the results of the nerve conduction studies. Logistic regression analysis and multiple regression analysis were used to evaluate correlations between significant risk factors and severity of diabetic polyneuropathy. Results The DM+PN group showed a significantly higher HbA1c level and composite score, as compared with the DM-PN group. Increased HbA1c level and old age were significant predictive factors for polyneuropathy in diabetic patients (odds ratio=5.233 and 4.745, respectively). In the multiple linear regression model, HbA1c and age showed a significant positive association with composite score, in order (β=1.560 and 0.253, respectively). Conclusion Increased HbA1c level indicative of a state of chronic hyperglycemia was a risk factor for polyneuropathy in diabetic patients and a quantitative measure of its severity. PMID:27152276

  1. Quantitative Study of Cell Invasion Process under Extracellular Stimulation of Cytokine in a Microfluidic Device

    PubMed Central

    Lei, Kin Fong; Tseng, Hsueh-Peng; Lee, Chia-Yi; Tsang, Ngan-Ming

    2016-01-01

    Cell invasion is the first step of cancer metastasis that is the primary cause of death for cancer patients and defined as cell movement through extracellular matrix (ECM). Investigation of the correlation between cell invasive and extracellular stimulation is critical for the inhabitation of metastatic dissemination. Conventional cell invasion assay is based on Boyden chamber assay, which has a number of limitations. In this work, a microfluidic device incorporating with impedance measurement technique was developed for quantitative investigation of cell invasion process. The device consisted of 2 reservoirs connecting with a microchannel filled with hydrogel. Malignant cells invaded along the microchannel and impedance measurement was concurrently conducted by measuring across electrodes located at the bottom of the microchannel. Therefore, cell invasion process could be monitored in real-time and non-invasive manner. Also, cell invasion rate was then calculated to study the correlation between cell invasion and extracellular stimulation, i.e., IL-6 cytokine. Results showed that cell invasion rate was directly proportional to the IL-6 concentration. The microfluidic device provides a reliable and convenient platform for cell-based assays to facilitate more quantitative assessments in cancer research. PMID:27150137

  2. Quantitative Study of Cell Invasion Process under Extracellular Stimulation of Cytokine in a Microfluidic Device.

    PubMed

    Lei, Kin Fong; Tseng, Hsueh-Peng; Lee, Chia-Yi; Tsang, Ngan-Ming

    2016-01-01

    Cell invasion is the first step of cancer metastasis that is the primary cause of death for cancer patients and defined as cell movement through extracellular matrix (ECM). Investigation of the correlation between cell invasive and extracellular stimulation is critical for the inhabitation of metastatic dissemination. Conventional cell invasion assay is based on Boyden chamber assay, which has a number of limitations. In this work, a microfluidic device incorporating with impedance measurement technique was developed for quantitative investigation of cell invasion process. The device consisted of 2 reservoirs connecting with a microchannel filled with hydrogel. Malignant cells invaded along the microchannel and impedance measurement was concurrently conducted by measuring across electrodes located at the bottom of the microchannel. Therefore, cell invasion process could be monitored in real-time and non-invasive manner. Also, cell invasion rate was then calculated to study the correlation between cell invasion and extracellular stimulation, i.e., IL-6 cytokine. Results showed that cell invasion rate was directly proportional to the IL-6 concentration. The microfluidic device provides a reliable and convenient platform for cell-based assays to facilitate more quantitative assessments in cancer research. PMID:27150137

  3. Clinical study of quantitative diagnosis of early cervical cancer based on the classification of acetowhitening kinetics

    NASA Astrophysics Data System (ADS)

    Wu, Tao; Cheung, Tak-Hong; Yim, So-Fan; Qu, Jianan Y.

    2010-03-01

    A quantitative colposcopic imaging system for the diagnosis of early cervical cancer is evaluated in a clinical study. This imaging technology based on 3-D active stereo vision and motion tracking extracts diagnostic information from the kinetics of acetowhitening process measured from the cervix of human subjects in vivo. Acetowhitening kinetics measured from 137 cervical sites of 57 subjects are analyzed and classified using multivariate statistical algorithms. Cross-validation methods are used to evaluate the performance of the diagnostic algorithms. The results show that an algorithm for screening precancer produced 95% sensitivity (SE) and 96% specificity (SP) for discriminating normal and human papillomavirus (HPV)-infected tissues from cervical intraepithelial neoplasia (CIN) lesions. For a diagnostic algorithm, 91% SE and 90% SP are achieved for discriminating normal tissue, HPV infected tissue, and low-grade CIN lesions from high-grade CIN lesions. The results demonstrate that the quantitative colposcopic imaging system could provide objective screening and diagnostic information for early detection of cervical cancer.

  4. Quantitative numerical and experimental studies of the shock accelerated heterogeneous bubbles motion

    NASA Astrophysics Data System (ADS)

    Layes, G.; Le Métayer, O.

    2007-04-01

    This work deals with quantitative comparisons between experimental and numerical results for shock-bubbles interactions. The bubbles are filled with three different gases (nitrogen, krypton and helium) surrounded by air in order to investigate all kind of density jumps across the interface. For each case, three incident shock wave intensities are also studied. The experiments are led by using a shock tube coupled with a visualization diagnostic device: the T80 shock tube [G. Jourdan, L. Houas, L. Schwaederlé, G. Layes, R. Carrey, and F. Diaz, "A new variable inclination shock tube for multiple investigations," Shock Waves 13, 501 (2004)]. Considering the same initial and geometrical conditions, the numerical results are obtained with the help of a recent numerical method: the discrete equations method [R. Abgrall and R. Saurel, "Discrete equations for physical and numerical compressible multiphase mixtures," J. Comput. Phys. 186, 361 (2003); R. Saurel, S. Gavrilyuk, and F. Renaud, "A multiphase model with internal degrees of freedom: Application to shock-bubble interaction," J. Fluid Mech. 495, 283 (2003); A. Chinnayya, E. Daniel, and R. Saurel, "Modelling detonation waves in heterogeneous energetic materials," J. Comput. Phys. 196, 490 (2004); O. Le Métayer, J. Massoni, and R. Saurel, "Modelling evaporation fronts with reactive Riemann solvers," J. Comput. Phys. 205, 567 (2005)], devoted to the computation of interface problems as well as multiphase mixtures. For each configuration, the quantitative comparisons are in good agreement showing the capability of both methods (numerical and experimental) to describe complex physical flows.

  5. Quantitative Study of Cell Invasion Process under Extracellular Stimulation of Cytokine in a Microfluidic Device

    NASA Astrophysics Data System (ADS)

    Lei, Kin Fong; Tseng, Hsueh-Peng; Lee, Chia-Yi; Tsang, Ngan-Ming

    2016-05-01

    Cell invasion is the first step of cancer metastasis that is the primary cause of death for cancer patients and defined as cell movement through extracellular matrix (ECM). Investigation of the correlation between cell invasive and extracellular stimulation is critical for the inhabitation of metastatic dissemination. Conventional cell invasion assay is based on Boyden chamber assay, which has a number of limitations. In this work, a microfluidic device incorporating with impedance measurement technique was developed for quantitative investigation of cell invasion process. The device consisted of 2 reservoirs connecting with a microchannel filled with hydrogel. Malignant cells invaded along the microchannel and impedance measurement was concurrently conducted by measuring across electrodes located at the bottom of the microchannel. Therefore, cell invasion process could be monitored in real-time and non-invasive manner. Also, cell invasion rate was then calculated to study the correlation between cell invasion and extracellular stimulation, i.e., IL-6 cytokine. Results showed that cell invasion rate was directly proportional to the IL-6 concentration. The microfluidic device provides a reliable and convenient platform for cell-based assays to facilitate more quantitative assessments in cancer research.

  6. In-vivo Tumor detection using diffusion reflection measurements of targeted gold nanorods - a quantitative study.

    PubMed

    Ankri, Rinat; Duadi, Hamootal; Motiei, Menachem; Fixler, Dror

    2012-03-01

    The ability to quantitatively and non-invasively detect nanoparticles has important implications on their development as an in-vivo cancer diagnostic tool. The Diffusion Reflection (DR) method is a simple, non-invasive imaging technique which has been proven useful for the investigation of tissue's optical parameters. In this study, Monte Carlo (MC) simulations, tissue-like phantom experiments and in-vivo measurements of the reflected light intensity from tumor bearing mice are presented. Following intravenous injection of antibody conjugated poly (ethylene glycol)-coated (PEGylated) gold nanorods (GNR) to tumor-bearing mice, accumulation of GNR in the tumor was clearly detected by the DR profile of the tumor. The ability of DR measurements to quantitate in-vivo the concentration of the GNR in the tumor was demonstrated and validated with Flame Atomic Absorption spectroscopy results. With GNR as absorbing contrast agents, DR has important potential applications in the image guided therapy of superficial tumors such as head and neck cancer, breast cancer and melanoma. PMID:22234916

  7. Quantitative and empirical demonstration of the Matthew effect in a study of career longevity

    PubMed Central

    Petersen, Alexander M.; Jung, Woo-Sung; Yang, Jae-Suk; Stanley, H. Eugene

    2011-01-01

    The Matthew effect refers to the adage written some two-thousand years ago in the Gospel of St. Matthew: “For to all those who have, more will be given.” Even two millennia later, this idiom is used by sociologists to qualitatively describe the dynamics of individual progress and the interplay between status and reward. Quantitative studies of professional careers are traditionally limited by the difficulty in measuring progress and the lack of data on individual careers. However, in some professions, there are well-defined metrics that quantify career longevity, success, and prowess, which together contribute to the overall success rating for an individual employee. Here we demonstrate testable evidence of the age-old Matthew “rich get richer” effect, wherein the longevity and past success of an individual lead to a cumulative advantage in further developing his or her career. We develop an exactly solvable stochastic career progress model that quantitatively incorporates the Matthew effect and validate our model predictions for several competitive professions. We test our model on the careers of 400,000 scientists using data from six high-impact journals and further confirm our findings by testing the model on the careers of more than 20,000 athletes in four sports leagues. Our model highlights the importance of early career development, showing that many careers are stunted by the relative disadvantage associated with inexperience. PMID:21173276

  8. A quantitative study of aromatic amine permeation through protective gloves using amine adsorptive pads.

    PubMed

    Vo, E; Berardinelli, S P; Hall, R C; El Ayouby, N

    2000-01-01

    A quantitative study of aromatic amine permeation through a glove material using Permea-Tec aromatic amine pads, used for the detection of chemical breakthrough of protective clothing, was performed for aniline following the microwave extraction process and gas chromatographic analysis. Aniline exhibited >99% adsorption on the pads at a spiking level of 1.94 mg (1.9 microL). Aniline showed recoveries from 65 to 89% (RSD < or =5.6%) over the range 1.1-1.9 microL (1.12-1.94 mg) of aniline applied to pads. The modified ASTM F739 and direct permeability testing procedures were used to determine breakthrough times for five protective glove materials using aniline as a challenge chemical. Breakthrough times for six protective gloves were determined, ranging from 182 sec to 82 min. The quantitative concentration of aniline on the pads following permeation through the gloves also was determined, ranging from 0.53 to 0.55 mg/cm2 (1.79-1.88 mg/pad). PMID:11192217

  9. Quantitative correlation of rainfall and earth surface displacements for slope stability studies

    NASA Astrophysics Data System (ADS)

    Steiakakis, Chrysanthos; Agioutantis, Zacharias; Apostolou, Evangelia; Papavgeri, Georgia; Tripolitsiotis, Achilleas

    2015-06-01

    It is common sense that the possibility of a rockfall increases after an intense rainfall and it is well documented that rainfalls accelerate earth surface displacements such as landslides and rockfalls. This qualitative correlation is highly affected by the geology and climate condition of the area under consideration. The research project entitled "Development of an integrated system for rockfall identification in highways", funded by the Operational Program Competitiveness and Entrepreneurship (co-funded by the European Regional Development Fund (ERDF)) aims to develop an operational system for early warning of rockfalls that occur along transportation corridors. To accomplish this goal the influence and the time gap between triggering mechanisms and rockfall incidents is investigated. In this work, previous studies towards quantitative correlation of rainfall magnitude and earth surface displacements are briefly presented. Based on these works, and taking into account that rockfall incidents, in the majority of Mediterranean countries, are not well-documented, data obtained by a slope stability monitoring network are used to quantitatively determine the magnitude of the rainfall that caused the slope's movement.

  10. Quantitative assessment of pupillary light reflex in normal and anesthetized dogs: a preliminary study.

    PubMed

    Kim, Jury; Heo, Jiseong; Ji, Dongbeom; Kim, Min-Su

    2015-04-01

    The purpose of this study was to quantitatively assess the pupillary light reflex (PLR) in normal and anesthetized dogs using a pupillometer. Eleven dogs (20 eyes) of various breeds were included. PLRs were measured with a handheld pupillometer in dim light before and during anesthesia. Anesthesia was conducted with atropine, xylazine and ketamine. Parameters of pupillometry included neurological pupil index (NPi), pupil size, percent of change (%CH), latency (LAT), constriction velocity (CV), maximum constriction velocity (MCV) and dilation velocity (DV). NPi,%CH, CV and MCV were significantly decreased during anesthesia compared with the pre-anesthesia data. The results suggest that atropine-xylazine-ketamine combination anesthesia depresses the PLR. Additionally, this study demonstrates the feasibility of the use of a pupillometer in dogs. PMID:25648149

  11. Early detection of cervical cancer among Native American women: a qualitative supplement to a quantitative study.

    PubMed

    Messer, L; Steckler, A; Dignan, M

    1999-08-01

    The North Carolina Native American Cervical Cancer Prevention Project was a 5-year (1989-1995) National Cancer Institute-funded, community-based, early detection of cervical cancer intervention implemented among two Native American tribes in North Carolina: the eastern band of the Cherokee Indians and the Lumbee. The initial quantitative analysis of the intervention showed modest effects and found that the intervention had different effects in the two communities. Due to the equivocal findings, a retrospective qualitative study was conducted. The qualitative study found that two types of factors influenced the intervention's results. The first were project and intervention characteristics, and the second were community and cultural factors over which the project had no control. The community and cultural factors took two forms: enhancers, which contributed to greater intervention effect, and attenuators, which created barriers to success. Examples of each factor are presented, and implications for cervical cancer detection among Native American women are discussed. PMID:10435237

  12. A quantitative study of chemical kinetics for the synthesis of doped oxide nanocrystals using FTIR

    PubMed Central

    Zhang, Na; Wang, Xin; Ye, Zhizhen; Jin, Yizheng

    2014-01-01

    The synthesis of Mg-doped ZnO nanocrystals was employed as a model system to quantitatively study the chemical kinetics of the precursor conversion reactions at synthetic conditions and the correlations with the formation of doped nanocrystals. An accurate method using Fourier transform infrared spectroscopy was developed to explore the alcoholysis reactions of the cationic precursors. Our study showed that three independent factors, molar ratio of dopant precursor, reaction temperature and coordination ligands of cationic precursors influenced the relative reactivity of magnesium to zinc precursor, and in turn the formation of Mg-doped ZnO nanocrystals with defined shapes and properties. This understanding underpins the advancement of the syntheses of doped nanocrystals and should be useful for future rational design of new synthetic systems. PMID:24619066

  13. A bibliometric analysis of the 50 most cited papers in cleft lip and palate.

    PubMed

    Mahon, Nicola A; Joyce, Cormac W

    2015-02-01

    Citation analysis is an established bibliometric method which catalogues papers according to the number of times they have been referenced. It is believed that the total number of citations an article receives reflects its importance among its peers. Never before has a bibliometric analysis been performed in the area of Cleft Lip and Palate. Our citation analysis creates a comprehensive list of the 50 most influential papers in this field. Journals specializing in Cleft Palate, Craniofacial, Plastic Surgery, Maxillofacial Surgery, Aesthetics and Radiology were searched to establish which articles most enriched the specialty over the past 70 years. The results show an interesting collection of papers which reveal developing trends in surgical techniques. These landmark papers mould and influence management and decision-making today. PMID:25196126

  14. Quantitative muscle strength assessment in duchenne muscular dystrophy: longitudinal study and correlation with functional measures

    PubMed Central

    2012-01-01

    Background The aim of this study was to perform a longitudinal assessment using Quantitative Muscle Testing (QMT) in a cohort of ambulant boys affected by Duchenne muscular dystrophy (DMD) and to correlate the results of QMT with functional measures. This study is to date the most thorough long-term evaluation of QMT in a cohort of DMD patients correlated with other measures, such as the North Star Ambulatory Assessment (NSAA) or thee 6-min walk test (6MWT). Methods This is a single centre, prospective, non-randomised, study assessing QMT using the Kin Com® 125 machine in a study cohort of 28 ambulant DMD boys, aged 5 to 12 years. This cohort was assessed longitudinally over a 12 months period of time with 3 monthly assessments for QMT and with assessment of functional abilities, using the NSAA and the 6MWT at baseline and at 12 months only. QMT was also used in a control group of 13 healthy age-matched boys examined at baseline and at 12 months. Results There was an increase in QMT over 12 months in boys below the age of 7.5 years while in boys above the age of 7.5 years, QMT showed a significant decrease. All the average one-year changes were significantly different than those experienced by healthy controls. We also found a good correlation between quantitative tests and the other measures that was more obvious in the stronger children. Conclusion Our longitudinal data using QMT in a cohort of DMD patients suggest that this could be used as an additional tool to monitor changes, providing additional information on segmental strength. PMID:22974002

  15. How fast is fisheries-induced evolution? Quantitative analysis of modelling and empirical studies

    PubMed Central

    Audzijonyte, Asta; Kuparinen, Anna; Fulton, Elizabeth A

    2013-01-01

    A number of theoretical models, experimental studies and time-series studies of wild fish have explored the presence and magnitude of fisheries-induced evolution (FIE). While most studies agree that FIE is likely to be happening in many fished stocks, there are disagreements about its rates and implications for stock viability. To address these disagreements in a quantitative manner, we conducted a meta-analysis of FIE rates reported in theoretical and empirical studies. We discovered that rates of phenotypic change observed in wild fish are about four times higher than the evolutionary rates reported in modelling studies, but correlation between the rate of change and instantaneous fishing mortality (F) was very similar in the two types of studies. Mixed-model analyses showed that in the modelling studies traits associated with reproductive investment and growth evolved slower than rates related to maturation. In empirical observations age-at-maturation was changing faster than other life-history traits. We also found that, despite different assumption and modelling approaches, rates of evolution for a given F value reported in 10 of 13 modelling studies were not significantly different. PMID:23789026

  16. Case-Based Lessons: A Quantitative Study of How Case Studies Impact Teacher Efficacy for the Application of Principles of Motivation

    ERIC Educational Resources Information Center

    O'Neil, Kathrine Pamela

    2012-01-01

    The purpose of this quantitative study was to provide a response to the following question: Does the use of video case studies focused on motivation increase undergraduates' sense of efficacy for applying principles of motivation? I examined the proposed research question using quantitative methods over the course of two 10-week quarters.…

  17. A bibliometric analysis of digestive health research in Canada

    PubMed Central

    Tuitt, Désirée; Knight, Frank; Lipman, Tara

    2011-01-01

    Measurement of the impact and influence of medical/scientific journals, and of individual researchers has become more widely practiced in recent decades. This is driven, in part, by the increased availability of data regarding citations of research articles, and by increased competition for research funding. Digestive disease research has been identified as a particularly strong discipline in Canada. The authors collected quantitative data on the impact and influence of Canadian digestive health research. The present study involved an analysis of the research impact (Hirsch factor) and research influence (Influence factor) of 106 digestive health researchers in Canada. Rankings of the top 25 researchers on the basis of the two metrics were dominated by the larger research groups at the University of Toronto (Toronto, Ontario), McMaster University (Hamilton, Ontario), and the Universities of Calgary (Calgary, Alberta) and Alberta (Edmonton, Alberta), but with representation by other research groups at the Universities of Manitoba (Winnipeg, Manitoba), Western Ontario (London, Ontario) and McGill University (Montreal, Quebec). Female and male researchers had similar scores for the two metrics, as did basic scientists versus clinical investigators. Strategic recruitment, particularly of established investigators, can have a major impact on the ranking of research groups. Comparing these metrics over different time frames can provide insights into the vulnerabilities and strengths of research groups. PMID:22059168

  18. A bibliometric analysis of digestive health research in Canada.

    PubMed

    Tuitt, Desiree; Knight, Frank; Lipman, Tara

    2011-11-01

    Measurement of the impact and influence of medical⁄scientific journals, and of individual researchers has become more widely practiced in recent decades. This is driven, in part, by the increased availability of data regarding citations of research articles, and by increased competition for research funding. Digestive disease research has been identified as a particularly strong discipline in Canada. The authors collected quantitative data on the impact and influence of Canadian digestive health research. The present study involved an analysis of the research impact (Hirsch factor) and research influence (Influence factor) of 106 digestive health researchers in Canada. Rankings of the top 25 researchers on the basis of the two metrics were dominated by the larger research groups at the University of Toronto (Toronto, Ontario), McMaster University (Hamilton, Ontario), and the Universities of Calgary (Calgary, Alberta) and Alberta (Edmonton, Alberta), but with representation by other research groups at the Universities of Manitoba (Winnipeg, Manitoba), Western Ontario (London, Ontario) and McGill University (Montreal, Quebec). Female and male researchers had similar scores for the two metrics, as did basic scientists versus clinical investigators. Strategic recruitment, particularly of established investigators, can have a major impact on the ranking of research groups. Comparing these metrics over different time frames can provide insights into the vulnerabilities and strengths of research groups. PMID:22059168

  19. The use of bibliometric indicators to help peer-review assessment.

    PubMed

    Haeffner-Cavaillon, Nicole; Graillot-Gak, Claude

    2009-01-01

    Inserm is the only French public research institution entirely dedicated to human health. Inserm supports research across the biomedical spectrum in all major disease areas, from fundamental lab-based science to clinical trials. To translate its scientists' findings into tangible health benefits, Inserm has its own affiliated company, Inserm Transfert, which works with industry. Since 2001, Inserm has been setting up on-line file management software for the evaluation of researchers and laboratories, called EVA ( www.eva.inserm.fr ). EVA includes all grant applications, assessment reports, evaluation grading evaluation forms and includes automated bibliometric indicator software that enables calculating, for example, the number of publications, journal impact factors, number of citations, citation index, and number of the Top 1 publications for each researcher of the teams. The indicators take into account research fields, the year of publications, and the author's position among the participants. Bibliometrics is now considered a tool for science policy providing indicators to measure productivity and scientific quality, thereby supplying a basis for evaluating and orienting R&D. It is also a potential tool for evaluation. It is neutral, allows comparative (national and international) assessment, and may select papers in the forefront in all fields. For each team, bibliometric indicators are calculated for all researchers with permanent or long-term positions (3-5 years). The use of bibliometric indicators requires great vigilance, but according to our experience they enrich the committee's debates without any doubt. We present an analysis of the data of 600 research teams evaluated in 2007-2008. PMID:19219530

  20. Lifelong bound feet in China: a quantitative ultrasound and lifestyle questionnaire study in postmenopausal women

    PubMed Central

    Qin, Ling; Pan, Yi; Zhang, Ming; Xu, Mian; Lao, Hanchang; O'Laughlin, Michael C; Tong, Shan; Zhao, Yanling; Hung, VWY; Cheng, JCY; Guo, Xia

    2015-01-01

    Objective The phenomenon of foot binding, also known as ‘lotus feet’, has an enduring and influential history in China. To achieve a man-made smaller foot size, lifelong foot binding may have had adverse effects on the skeleton. We investigated bone properties in postmenopausal women with bound feet, which may provide new information for developing countermeasures for prevention of fragility fractures. Design Population-based cohort study. Participants This study involved 254 postmenopausal women aged 65–80, including 172 with bound feet and 82 age- and gender-matched control subjects, living in a remote region of China. Outcomes Anthropometric, SF-36 Lifestyle Questionnaire and heel quantitative ultrasound (QUS) data were collected for the whole study population. A small subset of two cases was also invited for assessment of bone mineral density and microarchitecture at the distal tibia using high-resolution peripheral quantitative CT (HR-pQCT) and gait and balance tests. Results Women with bound feet had significantly lower QUS values than age-matched women with normal feet; this was supported by HR-pQCT data. However, SF-36 Questionnaire results did not reveal any statistically significant differences in any categorical responses, including physical functioning, general health vitality and physical component summary score, and number of previous fractures. No impairment of body balance was found in the small subset. Conclusions The man-made changes caused by foot binding led to reduced physical activity, making the subjects prone to osteoporosis. Women with bound feet and osteoporosis did not have a higher incidence of fragility fractures than controls. This might be explained by compensation in physical activity to improve body balance, implying the importance of improving or maintaining body balance in overall prevention strategies against fragility fractures. PMID:25783423

  1. Quantitative Amyloid Imaging in Autosomal Dominant Alzheimer’s Disease: Results from the DIAN Study Group

    PubMed Central

    Su, Yi; Blazey, Tyler M.; Owen, Christopher J.; Christensen, Jon J.; Friedrichsen, Karl; Joseph-Mathurin, Nelly; Wang, Qing; Hornbeck, Russ C.; Ances, Beau M.; Snyder, Abraham Z.; Cash, Lisa A.; Koeppe, Robert A.; Klunk, William E.; Galasko, Douglas; Brickman, Adam M.; McDade, Eric; Ringman, John M.; Thompson, Paul M.; Saykin, Andrew J.; Ghetti, Bernardino; Sperling, Reisa A.; Johnson, Keith A.; Salloway, Stephen P.; Schofield, Peter R.; Masters, Colin L.; Villemagne, Victor L.; Fox, Nick C.; Förster, Stefan; Chen, Kewei; Reiman, Eric M.; Xiong, Chengjie; Marcus, Daniel S.; Weiner, Michael W.; Morris, John C.; Bateman, Randall J.; Benzinger, Tammie L. S.

    2016-01-01

    Amyloid imaging plays an important role in the research and diagnosis of dementing disorders. Substantial variation in quantitative methods to measure brain amyloid burden exists in the field. The aim of this work is to investigate the impact of methodological variations to the quantification of amyloid burden using data from the Dominantly Inherited Alzheimer’s Network (DIAN), an autosomal dominant Alzheimer’s disease population. Cross-sectional and longitudinal [11C]-Pittsburgh Compound B (PiB) PET imaging data from the DIAN study were analyzed. Four candidate reference regions were investigated for estimation of brain amyloid burden. A regional spread function based technique was also investigated for the correction of partial volume effects. Cerebellar cortex, brain-stem, and white matter regions all had stable tracer retention during the course of disease. Partial volume correction consistently improves sensitivity to group differences and longitudinal changes over time. White matter referencing improved statistical power in the detecting longitudinal changes in relative tracer retention; however, the reason for this improvement is unclear and requires further investigation. Full dynamic acquisition and kinetic modeling improved statistical power although it may add cost and time. Several technical variations to amyloid burden quantification were examined in this study. Partial volume correction emerged as the strategy that most consistently improved statistical power for the detection of both longitudinal changes and across-group differences. For the autosomal dominant Alzheimer’s disease population with PiB imaging, utilizing brainstem as a reference region with partial volume correction may be optimal for current interventional trials. Further investigation of technical issues in quantitative amyloid imaging in different study populations using different amyloid imaging tracers is warranted. PMID:27010959

  2. A bibliometric analysis of NOAA's Office of Ocean Exploration and Research.

    PubMed

    Belter, Chris W

    2013-05-01

    Bibliometric analysis techniques are increasingly being used to analyze and evaluate scientific research produced by institutions and grant funding agencies. This article uses bibliometric methods to analyze journal articles funded by NOAA's Office of Ocean Exploration and Research (OER), an extramural grant-funding agency focused on the scientific exploration of the world's oceans. OER-supported articles in this analysis were identified through grant reports, personal communication, and acknowledgement of OER support or grant numbers. The articles identified were analyzed to determine the number of publications and citations received per year, subject, and institution. The productivity and citation impact of institutions in the US receiving OER grant funding were mapped geographically. Word co-occurrence and bibliographic coupling networks were created and visualized to identify the research topics of OER-supported articles. Finally, article citation counts were evaluated by means of percentile ranks. This article demonstrates that bibliometric analysis can be useful for summarizing and evaluating the research performance of a grant funding agency. PMID:23761945

  3. Quantitative cardiac SPECT in three dimensions: validation by experimental phantom studies

    NASA Astrophysics Data System (ADS)

    Liang, Z.; Ye, J.; Cheng, J.; Li, J.; Harrington, D.

    1998-04-01

    A mathematical framework for quantitative SPECT (single photon emission computed tomography) reconstruction of the heart is presented. An efficient simultaneous compensation approach to the reconstruction task is described. The implementation of the approach on a digital computer is delineated. The approach was validated by experimental data acquired from chest phantoms. The phantoms consisted of a cylindrical elliptical tank of Plexiglass, a cardiac insert made of Plexiglass, a spine insert of packed bone meal and lung inserts made of styrofoam beads alone. Water bags were added to simulate different body characteristics. Comparison between the quantitative reconstruction and the conventional FBP (filtered backprojection) method was performed. The FBP reconstruction had a poor quantitative accuracy and varied for different body configurations. Significant improvement in reconstruction accuracy by the quantitative approach was demonstrated with a moderate computing time on a currently available desktop computer. Furthermore, the quantitative reconstruction was robust for different body characteristics. Therefore, the quantitative approach has the potential for clinical use.

  4. Quantitative candidate gene association studies of metabolic traits in Han Chinese type 2 diabetes patients.

    PubMed

    Wei, F J; Cai, C Y; Yu, P; Lv, J; Ling, C; Shi, W T; Jiao, H X; Chang, B C; Yang, F H; Tian, Y; Li, M S; Wang, Y H; Zou, L; Shi, J M; Chen, L M; Li, W D

    2015-01-01

    Recent genome-wide association studies have identified many loci associated with type 2 diabetes mellitus (T2DM), hyperuricemia, and obesity in various ethnic populations. However, quantitative traits have been less well investigated in Han Chinese T2DM populations. We investigated the association between candidate gene single nucleotide polymorphisms (SNPs) and metabolic syndrome-related quantitative traits in Han Chinese T2DM subjects. Unrelated Han Chinese T2DM patients (1975) were recruited. Eighty-six SNPs were genotyped and tested for association with quantitative traits including lipid profiles, blood pressure, body mass index (BMI), serum uric acid (SUA), glycated hemoglobin (HbA1c), plasma glucose [fasting plasma glucose (FPG)], plasma glucose 120 min post-OGTT (P2PG; OGTT = oral glucose tolerance test), and insulin resistance-related traits. We found that CAMTA1, ABI2, VHL, KAT2B, PKHD1, ESR1, TOX, SLC30A8, SFI1, and MYH9 polymorphisms were associated with HbA1c, FPG, and/or P2PG; GCK, HHEX, TCF7L2, KCNQ1, and TBX5 polymorphisms were associated with insulin resistance-related traits; ABCG2, SLC2A9, and PKHD1 polymorphisms were associated with SUA; CAMTA1, VHL, KAT2B, PON1, NUB1, SLITRK5, SMAD3, FTO, FANCA, and PCSK2 polymorphisms were associated with blood lipid traits; CAMTA1, SPAG16, TOX, KCNQ1, ACACB, and MYH9 polymorphisms were associated with blood pressure; and UBE2E3, SPAG16, SLC2A9, CDKAL1, CDKN2A/B, TCF7L2, SMAD3, and PNPLA3 polymorphisms were associated with BMI (all P values <0.05). Some of the candidate genes were associated with metabolic and anthropometric traits in T2DM in Han Chinese. Although none of these associations reached genome-wide significance (P < 5 x 10(-8)), genes and loci identified in this study are worthy of further replication and investigation. PMID:26634513

  5. A quantitative μNRA study of helium intergranular and volume diffusion in sintered UO 2

    NASA Astrophysics Data System (ADS)

    Martin, G.; Desgardin, P.; Sauvage, T.; Garcia, P.; Carlot, G.; Khodja, H.; Barthe, M. F.

    2006-08-01

    To understand the mechanisms related to helium migration in nuclear oxide fuels, 3He was implanted at 2 × 1016 at. cm-2 in UO2 sintered disks. The samples were then annealed at temperatures ranging between 800 °C and 1300 °C. Changes in helium concentrations were investigated using two nuclear reaction analysis techniques based on the 3He(d, α)1H reaction. The first technique uses a macrobeam in order to measure helium depth profiles averaged over a 500 × 500 μm2 area. The second technique uses a microbeam and provides a quantitative two-dimensional helium concentration cartography, for which each pixel corresponds to a depth integrated helium signal. The analysed zones were optically characterised which enabled a detailed analysis of the impact of the material microstructure on helium release from the samples, with an emphasis on the study of grain boundary effects.

  6. Quantitative structure retention relationship studies for predicting relative retention times of chlorinated phenols on gas chromatography.

    PubMed

    Li, Shi-Yin; Sun, Cheng; Wang, Yu; Xu, Shi-Fen; Yao, Shu-Chun; Wang, Lian-Sheng

    2002-07-01

    A new method of quantitative structure-retention relationship (QSRR) studies was reported for predicting gas chromatography (GC) relative retention times (RRTs) of chlorinated phenols (CPs) using a DB-5 column. Chemical descriptors were calculated from the molecular structure of CPs and related to their gas chromatographic RRTs by using multiple linear regression analysis. The proposed model had a multiple square correlation coefficient R2 = 0.970, standard error SE = 0.0472, and significant level P = 0.0000. The QSRR model also reveals that the gas chromatographic relative retention times of CPs are associated with physicochemical property interactions with the stationary phase, and influenced by the number of chlorine and oxygen in the CP mOlecules. PMID:12211996

  7. Quantitative medical imaging: Initial studies of noncontact ultrasound applied to cortical bone phantoms

    NASA Astrophysics Data System (ADS)

    Halcrow, Peter William

    The purpose of this study was to take the initial steps towards applying Noncontact Ultrasound (NCU) to the in vivo monitoring of osteoporosis and to skeletal quantitative ultrasound imaging (QUS) using cortical bone phantoms. This project sought additional applications of NCU beyond its past limited usage in assessing third-degree burns. With this noncontact ultrasound imaging system, noncontact transducers and cortical bone phantoms with known bone mineral density (BMD) were used to determine speed of sound (SOS), integrated acoustical response (IR), and ultrasonic transmittance. Air gaps greater than 3 cm, two transmission and two reflection paths, and a digital signal processor were used to collect data. Significant correlations between BMD and measured SOS, IR, and transmittance were obtained. These NCU results were shown to be in agreement with results from contact ultrasound within 1-2%, which suggests that NCU might find additional applications in a clinical setting in the future in medical imaging.

  8. Quantitative sputum cell counts to monitor bronchitis: A qualitative study of physician and patient perspectives

    PubMed Central

    D’silva, Liesel; Neighbour, Helen; Gafni, Amiram; Radford, Katherine; Hargreave, Frederick E; Nair, Parameswaran

    2013-01-01

    Many common diseases affecting the airways are characterized by airway inflammation. The measurement of this inflammation has a significant role in the management of these diseases. Quantitative sputum cell counts provide a measurement of the type and severity of inflammation present. Sputum cell counts are used in routine clinical practice in some centres but their use is not widespread. The present study used a standardized questionnaire to determine both patients’ and physicians’ attitudes toward the use of sputum cell counts. The use of sputum cell counts was well accepted by patients and physicians. Ninety per cent of patients were satisfied with the test. Sixty per cent of family physicians were satisfied with the test and 80% were in favour of it being funded by the government. The authors recommend more widespread use of sputum cell counts to guide the management of airway diseases. PMID:23457675

  9. CNS effects of citalopram, a new serotonin inhibitor antidepressant (a quantitative pharmaco-electroencephalography study).

    PubMed

    Itil, T M; Menon, G N; Bozak, M M; Itil, K Z

    1984-01-01

    Citalopram, a new phthalane derivative and a specific serotonin re-uptake inhibitor in animal pharmacological tests, was evaluated in a double-blind, crossover, quantitative pharmaco-EEG (QPEEGTM) study in healthy human volunteers. The CNS effects of citalopram are linear, dose- and time-related, can statistically be differentiated from placebo, and indicate a rapid onset of effects with short duration. According to the Computer Data Bank, citalopram has a mode of action similar to mood elevators (antidepressants) with fewer sedative properties. Thus the therapeutic action of citalopram is predicted to be similar to desipramine and protriptyline from the tricyclics, and fluvoxamine from non-tricyclics. According to data bank assessment, it is hypothesized that the single antidepressant dose of citalopram is to be more than 25 mg, which should be given t.i.d. in clinical trials. PMID:6592676

  10. Characterization of the key aroma compounds in Shiraz wine by quantitation, aroma reconstitution, and omission studies.

    PubMed

    Mayr, Christine M; Geue, Jason P; Holt, Helen E; Pearson, Wes P; Jeffery, David W; Francis, I Leigh

    2014-05-21

    The key aroma compounds of premium Australian Shiraz wines from the warm Barossa Valley and cooler Margaret River regions were characterized. GC-Olfactometry was conducted to determine the most important volatile compounds, which were then quantitated. The wine from the Barossa Valley had higher concentrations of ethyl propanoate, dimethyl sulfide (DMS), and oak-derived compounds, whereas the Margaret River wine contained above threshold concentrations of the 'cheesy' compounds 2- and 3-methylbutanoic acid, as well as rotundone, the 'pepper'-smelling compound. The aromas were reconstituted by combining 44 aroma compounds, and sensory descriptive analysis was used to investigate the importance of the omission of several compounds, including DMS, rotundone, fatty acids, and β-damascenone, and the influence of nonvolatiles was also assessed. The study showed that the aroma of the Shiraz wines could be reconstituted in both cases, with the changes in the nonvolatile fraction having a large influence. PMID:24745791

  11. Inferring Quantitative Trait Pathways Associated with Bull Fertility from a Genome-Wide Association Study

    PubMed Central

    Peñagaricano, Francisco; Weigel, Kent A.; Rosa, Guilherme J. M.; Khatib, Hasan

    2013-01-01

    Whole-genome association studies typically focus on genetic markers with the strongest evidence of association. However, single markers often explain only a small component of the genetic variance and hence offer a limited understanding of the trait under study. As such, the objective of this study was to perform a pathway-based association analysis in Holstein dairy cattle in order to identify relevant pathways involved in bull fertility. The results of a single-marker association analysis, using 1,755 bulls with sire conception rate data and genotypes for 38,650 single nucleotide polymorphisms (SNPs), were used in this study. A total of 16,819 annotated genes, including 2,767 significantly associated with bull fertility, were used to interrogate a total of 662 Gene Ontology (GO) terms and 248 InterPro (IP) entries using a test of proportions based on the cumulative hypergeometric distribution. After multiple-testing correction, 20 GO categories and one IP entry showed significant overrepresentation of genes statistically associated with bull fertility. Several of these functional categories such as small GTPases mediated signal transduction, neurogenesis, calcium ion binding, and cytoskeleton are known to be involved in biological processes closely related to male fertility. These results could provide insight into the genetic architecture of this complex trait in dairy cattle. In addition, this study shows that quantitative trait pathways inferred from single-marker analyses could enhance our interpretations of the results of genome-wide association studies. PMID:23335935

  12. Involution of human fetal Leydig cells. An immunohistochemical, ultrastructural and quantitative study.

    PubMed Central

    Codesal, J; Regadera, J; Nistal, M; Regadera-Sejas, J; Paniagua, R

    1990-01-01

    The testes of stillborn fetuses (from 13 to 28 weeks of gestational age), fetuses born alive (from 29 weeks of gestational age) who died a few days later, and infants dying 1 to 8 months after birth were processed for light and electron microscopy. Paraffin-embedded material was stained with the avidin-biotin peroxidase complex (ABC) method for immunohistochemical detection of testosterone (T) in order to quantify the age-related changes in the number of T-positive interstitial cells. This number decreased progressively from the 24th week of gestation up to birth and remained unchanged up to the second month of postnatal life. During the third month of age, the number of T-positive cells rose markedly but fell again from the fourth month to the end of the study. The ultrastructural study revealed the following types of interstitial cells at all ages studied: fibroblast-like cells, myofibroblast-like cells, developed fetal Leydig cells, degenerating fetal Leydig cells and infantile Leydig cells with a multilobed nucleus and focal cytoplasmic accumulations of smooth endoplasmic reticulum and lipid droplets. Quantitative ultrastructural studies revealed that the changes in the number of fetal Leydig cells with age were similar to those found in the number of T-positive cells although, for each age studied, absolute values were higher in the ultrastructural study. The number of infantile Leydig cells increased with age. Images Figs. 1-4 Figs. 5-9 Figs. 10-11 PMID:2272896

  13. Quantitative study of effects of free cationic chains on gene transfection in different intracellular stages.

    PubMed

    Cai, Jinge; Yue, Yanan; Wang, Yanjing; Jin, Zhenyu; Jin, Fan; Wu, Chi

    2016-09-28

    Previously, we revealed that in the application of using cationic polymer chains, polyethylenimine (PEI), to condense anionic plasmid DNA chains (pDNA) to form the DNA/polymer polyplexes, after all the pDNAs are complexed with PEI, further added PEIs exist individual chains and free in the solution mixture. It is those uncomplexed polycation chains that dramatically promote the gene transfection. In the current study, we studied how those free cationic chains with different lengths and topologies affect the intracellular trafficking of the polyplexes, the translocation of pDNA through the nuclear membrane, the transcription of pDNA to mRNA and the translocation of mRNA from nucleus to cytosol in HepG2 cells by using a combination of the three-dimensional confocal microscope and TaqMan real-time PCR. We found that free branched PEI chains with a molar mass of 25,000g/mol and a total concentration of 1.8×10(-6)g/mL promote the overall gene transfection efficiency by a factor of ~500 times. Our results quantitatively reveal that free chains help little in the cellular uptake, but clearly reduce the lysosomal entrapment of those internalized polyplexes (2-3 folds); assist the translocation of pDNA through nuclear membrane after it is released from the polyplexes in the cytosol (~5 folds); enhance the pDNA-to-mRNA transcription efficiency (~4 folds); and facilitate the nucleus-to-cytosol translocation of mRNA (7-8 folds). The total enhancement of those steps agrees well with the overall efficiency, demonstrating, for the first time, how free cationic polymer chains quantitatively promote the gene transfection in each step in the intracellular space. PMID:27448443

  14. Quantitative electron microscopic study of the intracellular localization of wheat germ agglutinin in retinal neurons

    SciTech Connect

    Rhodes, C.H.; Stieber, A.; Gonatas, N.K.

    1986-12-15

    Previous work has established that, following endocytosis, wheat germ agglutinin, like a number of other plasma membrane bound ligands, is transported to the Golgi apparatus-complex. Previous studies that provided qualitative information about the intracellular distribution of internalized wheat germ agglutinin used techniques that precluded any quantitative conclusions about the relative magnitude of the labeling of endosomes, lysosomes, and the Golgi apparatus-complex. Using quantitative ultrastructural autoradiography, this study compares the time course and relative magnitude of labeling of various intracellular compartments to the labeling in the Golgi area. Fifteen minutes after intraocular injection, wheat germ agglutinin is confined to the inner surface of the retina and the immediate subsurface neuropil with little labeling of the retinal ganglion cell perikarya. Thirty minutes after injection, the plasma membrane (6.97 +/- 1.17), endosomes (10.27 +/- 3.98), smooth vesicles and tubules (1.94 +/- 1.66), and lysosomes (2.42 +/- 1.21) of the retinal ganglion cells are labeled, while the Golgi apparatus-complex is not labeled (0.29 +/- 0.25). The relative labeling density of the plasma membrane and endosomes decreases somewhat during the next 90 minutes (plasma membrane, 4.76 +/- 0.67; endosomes, 7.23 +/- 2.02), while the labeling density of smooth vesicles and tubules and of lysosomes rises (smooth vesicles and tubules, 5.56 +/- 0.94; lysosomes, 7.76 +/- 1.56). The Golgi apparatus-complex, which is unlabeled at 30 minutes, is weakly labeled at 2 hours (1.26 +/- 0.28).

  15. A combined post-mortem magnetic resonance imaging and quantitative histological study of multiple sclerosis pathology

    PubMed Central

    Kolasinski, James; Chance, Steven A.; DeLuca, Gabriele C.; Esiri, Margaret M.; Chang, Eun-Hyuk; Palace, Jacqueline A.; McNab, Jennifer A.; Jenkinson, Mark; Miller, Karla L.; Johansen-Berg, Heidi

    2012-01-01

    Multiple sclerosis is a chronic inflammatory neurological condition characterized by focal and diffuse neurodegeneration and demyelination throughout the central nervous system. Factors influencing the progression of pathology are poorly understood. One hypothesis is that anatomical connectivity influences the spread of neurodegeneration. This predicts that measures of neurodegeneration will correlate most strongly between interconnected structures. However, such patterns have been difficult to quantify through post-mortem neuropathology or in vivo scanning alone. In this study, we used the complementary approaches of whole brain post-mortem magnetic resonance imaging and quantitative histology to assess patterns of multiple sclerosis pathology. Two thalamo-cortical projection systems were considered based on their distinct neuroanatomy and their documented involvement in multiple sclerosis: lateral geniculate nucleus to primary visual cortex and mediodorsal nucleus of the thalamus to prefrontal cortex. Within the anatomically distinct thalamo-cortical projection systems, magnetic resonance imaging derived cortical thickness was correlated significantly with both a measure of myelination in the connected tract and a measure of connected thalamic nucleus cell density. Such correlations did not exist between these markers of neurodegeneration across different thalamo-cortical systems. Magnetic resonance imaging lesion analysis depicted clearly demarcated subcortical lesions impinging on the white matter tracts of interest; however, quantitation of the extent of lesion-tract overlap failed to demonstrate any appreciable association with the severity of markers of diffuse pathology within each thalamo-cortical projection system. Diffusion-weighted magnetic resonance imaging metrics in both white matter tracts were correlated significantly with a histologically derived measure of tract myelination. These data demonstrate for the first time the relevance of functional

  16. A Quantitative Study Investigating Supervisory Style, Satisfaction with Supervision and Self-Efficacy among Female Clinical Training Supervisees

    ERIC Educational Resources Information Center

    Terranova-Nirenberg, JoAnn

    2013-01-01

    This non-experimental quantitative study investigated the relationship between supervisory style, satisfaction with supervision, and the level of self-efficacy reported by the study participants. The study was based on counselor supervision theories found in the literature. The study investigated whether there was a difference between traditional…

  17. Understanding metal homeostasis in primary cultured neurons. Studies using single neuron subcellular and quantitative metallomics.

    PubMed

    Colvin, Robert A; Lai, Barry; Holmes, William R; Lee, Daewoo

    2015-07-01

    The purpose of this study was to demonstrate how single cell quantitative and subcellular metallomics inform us about both the spatial distribution and cellular mechanisms of metal buffering and homeostasis in primary cultured neurons from embryonic rat brain, which are often used as models of human disease involving metal dyshomeostasis. The present studies utilized synchrotron radiation X-ray fluorescence (SRXRF) and focused primarily on zinc and iron, two abundant metals in neurons that have been implicated in the pathogenesis of neurodegenerative diseases such as Alzheimer's disease and Parkinson's disease. Total single cell contents for calcium, iron, zinc, copper, manganese, and nickel were determined. Resting steady state zinc showed a diffuse distribution in both soma and processes, best defined by the mass profile of the neuron with an enrichment in the nucleus compared with the cytoplasm. Zinc buffering and homeostasis was studied using two modes of cellular zinc loading - transporter and ionophore (pyrithione) mediated. Single neuron zinc contents were shown to statistically significantly increase by either loading method - ionophore: 160 million to 7 billion; transporter 160 million to 280 million atoms per neuronal soma. The newly acquired and buffered zinc still showed a diffuse distribution. Soma and processes have about equal abilities to take up zinc via transporter mediated pathways. Copper levels are distributed diffusely as well, but are relatively higher in the processes relative to zinc levels. Prior studies have observed iron puncta in certain cell types, but others have not. In the present study, iron puncta were characterized in several primary neuronal types. The results show that iron puncta could be found in all neuronal types studied and can account for up to 50% of the total steady state content of iron in neuronal soma. Although other metals can be present in iron puncta, they are predominantly iron containing and do not appear to be

  18. Quantitative Evaluation of Macrophage Expression Using CD68 in Oral Submucous Fibrosis: An Immunohistochemical Study

    PubMed Central

    Pereira, T; Naik, S; Tamgadge, A

    2015-01-01

    Background: Macrophages are important cells for the innate immunity. Circulating monocytes are attracted to tissues by chemotactic factors and become macrophages under the influence of their microenvironment. Several studies suggested that local and systemic upregulation of fibrogenic cytokines and downregulation of antifibrotic cytokine are central to the pathogenesis of oral submucous fibrosis (OSMF). Currently, there have been no attempts made to elucidate the presence and role of macrophages in OSMF. Aim: Our aim was to study the expression of CD68 in OSMF patients and to investigate the possible correlation of macrophages using CD68 in various histopathological grades of OSMF. Subjects and Methods: A prospective case–control study which included 40 patients was conducted after obtaining informed consent and Ethical Committee clearance. Ten cases were normal control and thirty cases had OSMF. Biopsy was performed and a quantitative study of macrophages was done using CD68 antigen and was immunohistochemically localized. Statistical analysis was carried out using the Statistical Package for Social Sciences (SPSS) 17.0 version (SPSS Inc., Chicago, IL, USA). Results: OSMF was observed in male patients of a younger age group. The macrophage number in the patients of intermediate and advanced stage of OSMF was higher than that of the controls which was statistically significant (P < 0.05). Conclusion: The findings of this study suggest that CD68 plays a vital role in the pathogenesis of OSMF and can be regarded as a useful marker for assessing the progress of the disease. PMID:27057383

  19. Bibliometrics as a Performance Measurement Tool for Research Evaluation: The Case of Research Funded by the National Cancer Institute of Canada

    ERIC Educational Resources Information Center

    Campbell, David; Picard-Aitken, Michelle; Cote, Gregoire; Caruso, Julie; Valentim, Rodolfo; Edmonds, Stuart; Williams, Gregory Thomas; Macaluso, Benoit; Robitaille, Jean-Pierre; Bastien, Nicolas; Laframboise, Marie-Claude; Lebeau, Louis-Michel; Mirabel, Philippe; Lariviere, Vincent; Archambault, Eric

    2010-01-01

    As bibliometric indicators are objective, reliable, and cost-effective measures of peer-reviewed research outputs, they are expected to play an increasingly important role in research assessment/management. Recently, a bibliometric approach was developed and integrated within the evaluation framework of research funded by the National Cancer…

  20. A bibliometric analysis of toxicology research productivity in Middle Eastern Arab countries during a 10-year period (2003–2012)

    PubMed Central

    2014-01-01

    Background Bibliometric studies are increasingly being used for research assessment by involving the application of statistical methods to scientific publications to obtain the bibliographics for each country. The main objective of this study was to analyse the research productivity originating from 13 Middle Eastern Arab (MEA) countries with articles published in toxicology journals. Methods Data from January 1, 2003 till December 31, 2012 were searched for documents with specific words in the toxicology field as a “source title” in any one of the 13 MEA countries. Research productivity was evaluated based on a methodology developed and used in other bibliometric studies. Research productivity was adjusted to the national population and nominal gross domestic product (GDP) per capita. Results Documents (n = 1,240) were retrieved from 73 international peer-reviewed toxicology journals. The h-index of the retrieved documents was 39. Of the 73 journal titles, 52 (69.9%) have their IF listed in the ISI Journal Citation Reports 2012; 198 documents (16.0%) were published in journals that had no official IF. After adjusting for economy and population power, Egypt (193.6), Palestine (18.1), Kingdom of Saudi Arabia (KSA) (13.0), and Jordan (11.5) had the highest research productivity. Countries with large economies, such as the Kuwait, United Arab Emirates (UAE), and Oman, tended to rank relatively low after adjustment of GDP. The total number of citations at the time of data analysis (August 4, 2013) was 10,991, with a median (interquartile range) of 4 (1–11). MEA collaborated more with countries in the MEA regions (16.7%), especially KSA, Egypt, and UAE, followed by Europe (14.4%), especially with the United Kingdom and Germany. Conclusions The present data show a promising rise and a good start for toxicology research activity in toxicology journals in the Arab world. Research output is low in some countries, which can be improved by investing in more

  1. Pedagogical implications of approaches to study in distance learning: developing models through qualitative and quantitative analysis.

    PubMed

    Carnwell, R

    2000-05-01

    The need for flexibility in the delivery of nurse education has been identified by various initiatives including: widening the entry gate; continuous professional development; and the specialist practitioner. Access to degree level programmes is creating the need to acquire academic credit through flexible learning. The aim of this study was to further develop relationships between the need for guidance, materials design and learning styles and strategies and how these impact upon the construction of meaning. The study is based on interviews of 20 female community nurses purposively selected from the 96 respondents who had previously completed a survey questionnaire. The interviews were underpinned by theories relating to learning styles and approaches to study. Of particular concern was how these variables are mediated by student context, personal factors and materials design, to influence the need for support and guidance. The interview transcripts were first analysed using open and axial coding. Three approaches to study emerged from the data - systematic waders, speedy-focusers and global dippers - which were linked to other concepts and categories. Categories were then assigned numerical codes and subjected to logistical regression analysis. The attributes of the three approaches to study, arising from both qualitative and quantitative analysis, are explained in detail. The pedagogical implications of the three approaches to study are explained by their predicted relationships to other variables, such as support and guidance, organization of study, materials design and role of the tutor. The global dipper approach is discussed in more detail due to its association with a variety of predictor variables, not associated with the other two approaches to study. A feedback model is then developed to explore the impact of guidance on the global dipper approach. The paper makes recommendations for guidance to students using different approaches to study in distance

  2. Experimental study of flash boiling spray vaporization through quantitative vapor concentration and liquid temperature measurements

    NASA Astrophysics Data System (ADS)

    Zhang, Gaoming; Hung, David L. S.; Xu, Min

    2014-08-01

    Flash boiling sprays of liquid injection under superheated conditions provide the novel solutions of fast vaporization and better air-fuel mixture formation for internal combustion engines. However, the physical mechanisms of flash boiling spray vaporization are more complicated than the droplet surface vaporization due to the unique bubble generation and boiling process inside a superheated bulk liquid, which are not well understood. In this study, the vaporization of flash boiling sprays was investigated experimentally through the quantitative measurements of vapor concentration and liquid temperature. Specifically, the laser-induced exciplex fluorescence technique was applied to distinguish the liquid and vapor distributions. Quantitative vapor concentration was obtained by correlating the intensity of vapor-phase fluorescence with vapor concentration through systematic corrections and calibrations. The intensities of two wavelengths were captured simultaneously from the liquid-phase fluorescence spectra, and their intensity ratios were correlated with liquid temperature. The results show that both liquid and vapor phase of multi-hole sprays collapse toward the centerline of the spray with different mass distributions under the flash boiling conditions. Large amount of vapor aggregates along the centerline of the spray to form a "gas jet" structure, whereas the liquid distributes more uniformly with large vortexes formed in the vicinity of the spray tip. The vaporization process under the flash boiling condition is greatly enhanced due to the intense bubble generation and burst. The liquid temperature measurements show strong temperature variations inside the flash boiling sprays with hot zones present in the "gas jet" structure and vortex region. In addition, high vapor concentration and closed vortex motion seem to have inhibited the heat and mass transfer in these regions. In summary, the vapor concentration and liquid temperature provide detailed information

  3. Quantitative Ultrasonic Evaluation of Radiation-Induced Late Tissue Toxicity: Pilot Study of Breast Cancer Radiotherapy

    SciTech Connect

    Liu Tian; Zhou Jun; Yoshida, Emi J.; Woodhouse, Shermian A.; Schiff, Peter B.; Wang, Tony J.C.; Lu Zhengfeng; Pile-Spellman, Eliza; Zhang Pengpeng; Kutcher, Gerald J.

    2010-11-01

    Purpose: To investigate the use of advanced ultrasonic imaging to quantitatively evaluate normal-tissue toxicity in breast-cancer radiation treatment. Methods and Materials: Eighteen breast cancer patients who received radiation treatment were enrolled in an institutional review board-approved clinical study. Radiotherapy involved a radiation dose of 50.0 to 50.4 Gy delivered to the entire breast, followed by an electron boost of 10.0 to 16.0 Gy delivered to the tumor bed. Patients underwent scanning with ultrasound during follow-up, which ranged from 6 to 94 months (median, 22 months) postradiotherapy. Conventional ultrasound images and radio-frequency (RF) echo signals were acquired from treated and untreated breasts. Three ultrasound parameters, namely, skin thickness, Pearson coefficient, and spectral midband fit, were computed from RF signals to measure radiation-induced changes in dermis, hypodermis, and subcutaneous tissue, respectively. Ultrasound parameter values of the treated breast were compared with those of the untreated breast. Ultrasound findings were compared with clinical assessment using Radiation Therapy Oncology Group (RTOG) late-toxicity scores. Results: Significant changes were observed in ultrasonic parameter values of the treated vs. untreated breasts. Average skin thickness increased by 27.3%, from 2.05 {+-} 0.22mm to 2.61 {+-} 0.52mm; Pearson coefficient decreased by 31.7%, from 0.41 {+-} 0.07 to 0.28 {+-} 0.05; and midband fit increased by 94.6%, from -0.92 {+-} 7.35 dB to 0.87 {+-} 6.70 dB. Ultrasound evaluations were consistent with RTOG scores. Conclusions: Quantitative ultrasound provides a noninvasive, objective means of assessing radiation-induced changes to the skin and subcutaneous tissue. This imaging tool will become increasingly valuable as we continue to improve radiation therapy technique.

  4. Spectroscopic and Chemometric Analysis of Binary and Ternary Edible Oil Mixtures: Qualitative and Quantitative Study.

    PubMed

    Jović, Ozren; Smolić, Tomislav; Primožič, Ines; Hrenar, Tomica

    2016-04-19

    The aim of this study was to investigate the feasibility of FTIR-ATR spectroscopy coupled with the multivariate numerical methodology for qualitative and quantitative analysis of binary and ternary edible oil mixtures. Four pure oils (extra virgin olive oil, high oleic sunflower oil, rapeseed oil, and sunflower oil), as well as their 54 binary and 108 ternary mixtures, were analyzed using FTIR-ATR spectroscopy in combination with principal component and discriminant analysis, partial least-squares, and principal component regression. It was found that the composition of all 166 samples can be excellently represented using only the first three principal components describing 98.29% of total variance in the selected spectral range (3035-2989, 1170-1140, 1120-1100, 1093-1047, and 930-890 cm(-1)). Factor scores in 3D space spanned by these three principal components form a tetrahedral-like arrangement: pure oils being at the vertices, binary mixtures at the edges, and ternary mixtures on the faces of a tetrahedron. To confirm the validity of results, we applied several cross-validation methods. Quantitative analysis was performed by minimization of root-mean-square error of cross-validation values regarding the spectral range, derivative order, and choice of method (partial least-squares or principal component regression), which resulted in excellent predictions for test sets (R(2) > 0.99 in all cases). Additionally, experimentally more demanding gas chromatography analysis of fatty acid content was carried out for all specimens, confirming the results obtained by FTIR-ATR coupled with principal component analysis. However, FTIR-ATR provided a considerably better model for prediction of mixture composition than gas chromatography, especially for high oleic sunflower oil. PMID:26971405

  5. Intraoral somatosensory abnormalities in patients with atypical odontalgia – a controlled multicenter quantitative sensory testing study

    PubMed Central

    Baad-Hansen, Lene; Pigg, Maria; Ivanovic, Susanne El’Masry; Faris, Hanan; List, Thomas; Drangsholt, Mark; Svensson, Peter

    2013-01-01

    Intraoral somatosensory sensitivity in patients with atypical odontalgia (AO) has not been investigated systematically according to the most recent guidelines. The aims of this study were to: 1. Examine intraoral somatosensory disturbances in AO patients using healthy subjects as reference and 2. Evaluate the percent agreement between intraoral quantitative sensory testing (QST) and qualitative sensory testing (QualST). Forty-seven AO patients and 69 healthy controls were included at Universities of Washington, Malmö and Aarhus. In AO patients, intraoral somatosensory testing was performed on the painful site, the corresponding contralateral site and at thenar. In healthy subjects, intraoral somatosensory testing was performed bilaterally on the upper premolar gingiva and at thenar. Thirteen QST and 3 QualST parameters were evaluated at each site, z-scores were computed for AO patients based on the healthy reference material and LossGain scores were created. 87.3% of AO patients had QST abnormalities compared with controls. The most frequent somatosensory abnormalities in AO patients were somatosensory gain with regard to painful mechanical and cold stimuli and somatosensory loss with regard to cold detection and mechanical detection. The most frequent LossGain code was L0G2 (no somatosensory loss with gain of mechanical somatosensory function)(31.9% of AO patients). Percent agreement between corresponding QST and QualST measures of thermal and mechanical sensitivity ranged between 55.6 and 70.4% in AO patients and between 71.1 and 92.1% in controls. In conclusion, intraoral somatosensory abnormalities were commonly detected in AO patients and agreement between quantitative and qualitative sensory testing was good to excellent. PMID:23725780

  6. Intraoral somatosensory abnormalities in patients with atypical odontalgia--a controlled multicenter quantitative sensory testing study.

    PubMed

    Baad-Hansen, Lene; Pigg, Maria; Ivanovic, Susanne Eímasry; Faris, Hanan; List, Thomas; Drangsholt, Mark; Svensson, Peter

    2013-08-01

    Intraoral somatosensory sensitivity in patients with atypical odontalgia (AO) has not been investigated systematically according to the most recent guidelines. The aims of this study were to examine intraoral somatosensory disturbances in AO patients using healthy subjects as reference, and to evaluate the percent agreement between intraoral quantitative sensory testing (QST) and qualitative sensory testing (QualST). Forty-seven AO patients and 69 healthy control subjects were included at Universities of Washington, Malmö, and Aarhus. In AO patients, intraoral somatosensory testing was performed on the painful site, the corresponding contralateral site, and at thenar. In healthy subjects, intraoral somatosensory testing was performed bilaterally on the upper premolar gingiva and at thenar. Thirteen QST and 3 QualST parameters were evaluated at each site, z-scores were computed for AO patients based on the healthy reference material, and LossGain scores were created. Compared with control subjects, 87.3% of AO patients had QST abnormalities. The most frequent somatosensory abnormalities in AO patients were somatosensory gain with regard to painful mechanical and cold stimuli and somatosensory loss with regard to cold detection and mechanical detection. The most frequent LossGain code was L0G2 (no somatosensory loss with gain of mechanical somatosensory function) (31.9% of AO patients). Percent agreement between corresponding QST and QualST measures of thermal and mechanical sensitivity ranged between 55.6% and 70.4% in AO patients and between 71.1% and 92.1% in control subjects. In conclusion, intraoral somatosensory abnormalities were commonly detected in AO patients, and agreement between quantitative and qualitative sensory testing was good to excellent. PMID:23725780

  7. Quantitative Fluorescence Studies in Living Cells: Extending Fluorescence Fluctuation Spectroscopy to Peripheral Membrane Proteins

    NASA Astrophysics Data System (ADS)

    Smith, Elizabeth Myhra

    The interactions of peripheral membrane proteins with both membrane lipids and proteins are vital for many cellular processes including membrane trafficking, cellular signaling, and cell growth/regulation. Building accurate biophysical models of these processes requires quantitative characterization of the behavior of peripheral membrane proteins, yet methods to quantify their interactions inside living cells are very limited. Because peripheral membrane proteins usually exist both in membrane-bound and cytoplasmic forms, the separation of these two populations is a key challenge. This thesis aims at addressing this challenge by extending fluorescence fluctuation spectroscopy (FFS) to simultaneously measure the oligomeric state of peripheral membrane proteins in the cytoplasm and at the plasma membrane. We developed a new method based on z-scan FFS that accounts for the fluorescence contributions from cytoplasmic and membrane layers by incorporating a fluorescence intensity z-scan through the cell. H-Ras-EGFP served as a model system to demonstrate the feasibility of the technique. The resolvability and stability of z-scanning was determined as well as the oligomeric state of H-Ras-EGFP at the plasma membrane and in the cytoplasm. Further, we successfully characterized the binding affinity of a variety of proteins to the plasma membrane by quantitative analysis of the z-scan fluorescence intensity profile. This analysis method, which we refer to as z-scan fluorescence profile deconvoution, was further used in combination with dual-color competition studies to determine the lipid specificity of protein binding. Finally, we applied z-scan FFS to provide insight into the early assembly steps of the HTLV-1 retrovirus.

  8. Hydroponic isotope labelling of entire plants (HILEP) for quantitative plant proteomics; an oxidative stress case study.

    PubMed

    Bindschedler, Laurence V; Palmblad, Magnus; Cramer, Rainer

    2008-07-01

    Hydroponic isotope labelling of entire plants (HILEP) is a cost-effective method enabling metabolic labelling of whole and mature plants with a stable isotope such as (15)N. By utilising hydroponic media that contain (15)N inorganic salts as the sole nitrogen source, near to 100% (15)N-labelling of proteins can be achieved. In this study, it is shown that HILEP, in combination with mass spectrometry, is suitable for relative protein quantitation of seven week-old Arabidopsis plants submitted to oxidative stress. Protein extracts from pooled (14)N- and (15)N-hydroponically grown plants were fractionated by SDS-PAGE, digested and analysed by liquid chromatography electrospray ionisation tandem mass spectrometry (LC-ESI-MS/MS). Proteins were identified and the spectra of (14)N/(15)N peptide pairs were extracted using their m/z chromatographic retention time, isotopic distributions, and the m/z difference between the (14)N and (15)N peptides. Relative amounts were calculated as the ratio of the sum of the peak areas of the two distinct (14)N and (15)N peptide isotope envelopes. Using Mascot and the open source trans-proteomic pipeline (TPP), the data processing was automated for global proteome quantitation down to the isoform level by extracting isoform specific peptides. With this combination of metabolic labelling and mass spectrometry it was possible to show differential protein expression in the apoplast of plants submitted to oxidative stress. Moreover, it was possible to discriminate between differentially expressed isoforms belonging to the same protein family, such as isoforms of xylanases and pathogen-related glucanases (PR 2). PMID:18538804

  9. A quasi-experimental quantitative study of the effect of IB on science performance

    NASA Astrophysics Data System (ADS)

    Healer, Margaret Irene

    The purpose of this quasi-experimental quantitative research study was to investigate the effect of participation in the International Baccalaureate (IB) program on science performance. The findings of the 2x3 mixed ANOVA and Eta square analysis indicated a significant difference (in science CSAP mean scores between the treatment group: IB students ( n = 50) and the control group: non-IB students (n = 50) at the 5th through 10th grade level. The analysis of data concluded that although scores declined between 5th, 8th, and 10th grades with IB and non-IB students, a statistical difference was indicated at each level between the two groups: IB and non-IB in the area of science performance as measured by the CSAP assessment. Educational leaders can use the findings of this study to maximize student science achievement. Further research is recommended through a mixed study to determine the effectiveness of participation in the IB Program and a study of specificity of pedagogical strategies used with science performance with a larger sample size of IB and non-IB students longitudinally.

  10. Quantitative evaluation of reactive nitrogen emissions with urbanization: a case study in Beijing megacity, China.

    PubMed

    Xian, Chaofan; Ouyang, Zhiyun; Lu, Fei; Xiao, Yang; Li, Yanmin

    2016-09-01

    The rapid increase in anthropogenic nitrogen (N) load in urbanized environment threatens urban sustainability. In this study, we estimated the amount of reactive N (Nr) as an index of N pollution potential caused by human activities, using the megacity of Beijing as a case study. We investigated the temporal changes in Nr emissions in the environment from 2000 to 2012 using a multidisciplinary approach with quantitative evaluation. The Nr emissions presented slightly increasing during study period, and the annual emission was 0.19 Tg N, mainly resulting from fuel combustion. Nevertheless, the Nr output intensity resulting from inhabitants' livelihoods and material production had weakened over the study period. The evaluation results showed that the environmental measures to remove Nr in Beijing were efficient in most years, suggesting that progress in mitigating the growth of the Nr load in this urban environment was significant. Further measures based on N offset are suggested that could help alleviate the environmental pressure resulting from anthropogenic Nr emissions. These could provide theoretical support for the sustainable development of megacities. PMID:27240830

  11. The Quantitative Ethology of the Zebra Finch: A Study in Comparative Psychometrics.

    ERIC Educational Resources Information Center

    Figueredo, Aurelio Jose; And Others

    1992-01-01

    A quantitative ethogram was developed for the zebra finch, using one-zero focal animal sampling on an ethologically comprehensive checklist of 52 behavioral items, and it was assessed for interobserver reliability and construct validity. Applying the quantitative methods of psychometrics allows verification of ethological theory and testing of…

  12. Effects of Quantitative Linguistic Feedback to Caregivers of Young Children: A Pilot Study in China

    ERIC Educational Resources Information Center

    Zhang, Yiwen; Xu, Xiaojuan; Jiang, Fan; Gilkerson, Jill; Xu, Dongxin; Richards, Jeffrey A.; Harnsberger, James; Topping, Keith J.

    2015-01-01

    Changes in natural language environments of families receiving quantitative language feedback in Shanghai were investigated. Volunteer parents of 22 children aged 5 to 30 months were recruited from a hospital and a learning center. Quantitative measures of adult word count and conversational turns with children were collected regularly over 6…

  13. Study Quality in SLA: An Assessment of Designs, Analyses, and Reporting Practices in Quantitative L2 Research

    ERIC Educational Resources Information Center

    Plonsky, Luke

    2013-01-01

    This study assesses research and reporting practices in quantitative second language (L2) research. A sample of 606 primary studies, published from 1990 to 2010 in "Language Learning and Studies in Second Language Acquisition," was collected and coded for designs, statistical analyses, reporting practices, and outcomes (i.e., effect…

  14. ICQ (I seek you) and adolescents: a quantitative study in Hong Kong.

    PubMed

    Cheuk, W S; Chan, Zenobia C Y

    2007-02-01

    The Hong Kong Government and the education sector encourage the whole population-from toddlers to senior citizens-to utilize information technology, and many do. Yet there are no studies exploring the patterns of adolescents using ICQ (I seek you) in Asian countries. This study was done in Hong Kong, which has the greatest number of ICQ users. A quantitative approach was adopted by administering self-constructed questionnaires to the students of one high school. One hundred and forty-seven adolescents volunteered to participate. The key findings of the study are (1) most of the adolescents have been using ICQ for 1-4 years; (2) most fit one of two patterns of use: either 2 or 3 days per week, or more than 5 days per week; (3) they spend less than 3 h per day on ICQ; (4) the main reasons for using ICQ are entertainment, relaxation, and socializing; and (5) parents are concerned about possible negative impacts on their children's academic performance because of using ICQ. Two main implications are drawn: proper use of ICQ can minimize parental distress and encourage adolescents to be less sedentary. PMID:17305456

  15. ARGET–ATRP Synthesis and Characterization of PNIPAAm Brushes for Quantitative Cell Detachment Studies

    PubMed Central

    Shivapooja, Phanindhar; Ista, Linnea K.; Canavan, Heather E.; Lopez, Gabriel P.

    2012-01-01

    Stimuli responsive (or “smart”) polymer brushes represent a non-toxic approach for achieving release of biofouling layers. Thermo-responsive poly(N-isopropylacrylamide) (PNIPAAm) polymer brushes have been shown to modulate bacterial adhesion and release through transition between temperatures above and below the lower critical solution temperature (LCST ~32 °C) of PNIPAAm in water. In this article, we describe a convenient method to synthesize grafted PNIPAAm brushes over large areas for biological studies using a relatively simple and rapid method which allows atom transfer radical polymerization (ATRP) in presence of air using the activator regenerated electron transfer (ARGET) mechanism. PNIPAAm brushes were characterized using X-ray photoelectron spectroscopy, time-of-flight secondary ion mass spectroscopy, Fourier transform infrared spectroscopy, ellipsometry, and contact angle measurements. Our studies demonstrate that uniform, high purity PNIPAAm brushes with controlled and high molecular weight can be easily produced over large areas using ARGET–ATRP. We also report the use of a spinning disk apparatus to systematically and quantitatively study the detachment profiles of bacteria from PNIPAAm surfaces under a range (0–400 dyne/cm2) of shear stresses. PMID:22589075

  16. Quantitative studies of animal colour constancy: using the chicken as model.

    PubMed

    Olsson, Peter; Wilby, David; Kelber, Almut

    2016-05-11

    Colour constancy is the capacity of visual systems to keep colour perception constant despite changes in the illumination spectrum. Colour constancy has been tested extensively in humans and has also been described in many animals. In humans, colour constancy is often studied quantitatively, but besides humans, this has only been done for the goldfish and the honeybee. In this study, we quantified colour constancy in the chicken by training the birds in a colour discrimination task and testing them in changed illumination spectra to find the largest illumination change in which they were able to remain colour-constant. We used the receptor noise limited model for animal colour vision to quantify the illumination changes, and found that colour constancy performance depended on the difference between the colours used in the discrimination task, the training procedure and the time the chickens were allowed to adapt to a new illumination before making a choice. We analysed literature data on goldfish and honeybee colour constancy with the same method and found that chickens can compensate for larger illumination changes than both. We suggest that future studies on colour constancy in non-human animals could use a similar approach to allow for comparison between species and populations. PMID:27170714

  17. Validation of reference genes for real-time quantitative RT-PCR studies in Talaromyces marneffei.

    PubMed

    Dankai, Wiyada; Pongpom, Monsicha; Vanittanakom, Nongnuch

    2015-11-01

    Talaromyces marneffei (or Penicillium marneffei) is an opportunistic pathogen that can cause disseminated disease in human immunodeficiency virus (HIV)-infected patients, especially in Southeast Asia. T. marneffei is a thermally dimorphic fungus. Typically, T. marneffei has an adaptive morphology. It grows in a filamentous form (mould) at 25°C and can differentiate to produce asexual spores (conidia). In contrast, at 37°C, it grows as yeast cells that divide by fission. This study aimed to validate a quantitative reverse-transcription polymerase chain reaction (qRT-PCR) for gene expression analysis in T. marneffei. Analysis of relative gene expression by qRT-PCR requires normalization of data using a proper reference gene. However, suitable reference genes have not been identified in gene expression studies across different cell types or under different experimental conditions in T. marneffei. In this study, four housekeeping genes were selected for analysis: β-actin (act); glyceraldehyde-3-phosphate dehydrogenase (gapdh); β-tubulin (benA) and 18S rRNA. Two analysis programs; BestKeeper and geNorm software tools were used to validate the expression of the candidate normalized genes. The results indicated that the actin gene was the one which was most stably expressed and was recommended for use as the endogenous control for gene expression analysis of all growth forms in T. marneffei by qRT-PCR under normal and stress conditions. PMID:26327538

  18. Quantitative Assessment of Eye Phenotypes for Functional Genetic Studies Using Drosophila melanogaster.

    PubMed

    Iyer, Janani; Wang, Qingyu; Le, Thanh; Pizzo, Lucilla; Grönke, Sebastian; Ambegaokar, Surendra S; Imai, Yuzuru; Srivastava, Ashutosh; Troisí, Beatriz Llamusí; Mardon, Graeme; Artero, Ruben; Jackson, George R; Isaacs, Adrian M; Partridge, Linda; Lu, Bingwei; Kumar, Justin P; Girirajan, Santhosh

    2016-01-01

    About two-thirds of the vital genes in the Drosophila genome are involved in eye development, making the fly eye an excellent genetic system to study cellular function and development, neurodevelopment/degeneration, and complex diseases such as cancer and diabetes. We developed a novel computational method, implemented as Flynotyper software (http://flynotyper.sourceforge.net), to quantitatively assess the morphological defects in the Drosophila eye resulting from genetic alterations affecting basic cellular and developmental processes. Flynotyper utilizes a series of image processing operations to automatically detect the fly eye and the individual ommatidium, and calculates a phenotypic score as a measure of the disorderliness of ommatidial arrangement in the fly eye. As a proof of principle, we tested our method by analyzing the defects due to eye-specific knockdown of Drosophila orthologs of 12 neurodevelopmental genes to accurately document differential sensitivities of these genes to dosage alteration. We also evaluated eye images from six independent studies assessing the effect of overexpression of repeats, candidates from peptide library screens, and modifiers of neurotoxicity and developmental processes on eye morphology, and show strong concordance with the original assessment. We further demonstrate the utility of this method by analyzing 16 modifiers of sine oculis obtained from two genome-wide deficiency screens of Drosophila and accurately quantifying the effect of its enhancers and suppressors during eye development. Our method will complement existing assays for eye phenotypes, and increase the accuracy of studies that use fly eyes for functional evaluation of genes and genetic interactions. PMID:26994292

  19. Quantitative Assessment of Eye Phenotypes for Functional Genetic Studies Using Drosophila melanogaster

    PubMed Central

    Iyer, Janani; Wang, Qingyu; Le, Thanh; Pizzo, Lucilla; Grönke, Sebastian; Ambegaokar, Surendra S.; Imai, Yuzuru; Srivastava, Ashutosh; Troisí, Beatriz Llamusí; Mardon, Graeme; Artero, Ruben; Jackson, George R.; Isaacs, Adrian M.; Partridge, Linda; Lu, Bingwei; Kumar, Justin P.; Girirajan, Santhosh

    2016-01-01

    About two-thirds of the vital genes in the Drosophila genome are involved in eye development, making the fly eye an excellent genetic system to study cellular function and development, neurodevelopment/degeneration, and complex diseases such as cancer and diabetes. We developed a novel computational method, implemented as Flynotyper software (http://flynotyper.sourceforge.net), to quantitatively assess the morphological defects in the Drosophila eye resulting from genetic alterations affecting basic cellular and developmental processes. Flynotyper utilizes a series of image processing operations to automatically detect the fly eye and the individual ommatidium, and calculates a phenotypic score as a measure of the disorderliness of ommatidial arrangement in the fly eye. As a proof of principle, we tested our method by analyzing the defects due to eye-specific knockdown of Drosophila orthologs of 12 neurodevelopmental genes to accurately document differential sensitivities of these genes to dosage alteration. We also evaluated eye images from six independent studies assessing the effect of overexpression of repeats, candidates from peptide library screens, and modifiers of neurotoxicity and developmental processes on eye morphology, and show strong concordance with the original assessment. We further demonstrate the utility of this method by analyzing 16 modifiers of sine oculis obtained from two genome-wide deficiency screens of Drosophila and accurately quantifying the effect of its enhancers and suppressors during eye development. Our method will complement existing assays for eye phenotypes, and increase the accuracy of studies that use fly eyes for functional evaluation of genes and genetic interactions. PMID:26994292

  20. Biopharmaceutical characterization of oral theophylline and aminophylline tablets. Quantitative correlation between dissolution and bioavailability studies.

    PubMed

    Varshosaz, J; Ghafghazi, T; Raisi, A; Falamarzian, M

    2000-09-01

    Considering the narrow therapeutic index of theophylline and the low range between the safe and toxic serum concentrations of this drug, the study of its pharmacokinetic properties is necessary. However, considering the time consuming and expensive in vivo tests, quantitative correlation between in vivo bioavailability and in vitro dissolution tests can be used routinely in quality control tests of these drug products to predict the in vivo pharmacokinetic parameters. For this reason healthy human volunteers were used for in vivo studies and serum samples were analyzed by a fluorescence polarization immunoassay analysis (FPIA) method. The results showed that an open one compartmental model could best describe the pharmacokinetic properties of orally administered theophylline and aminophylline tablets. Linear regression analysis by least-square method showed a good correlation between some in vivo and in vitro parameters obtained from dissolution studies by rotating basket and paddle methods. D(30)% (percentage of drug dissolved in vitro after 30 min) and F(0.5)% (drug absorbed in vivo after half an hour calculated by Wagner-Nelson equation) showed best correlation (r=0. 99036). C(max) (maximum serum concentration) of this drug also correlates well with t(25%) (time required to dissolve 25% of the drug). The calculated correlation coefficients could best predict the actual values of some pharmacokinetic parameters; AUC(0-->infinity), AUC(0-->1), F(0.5)% and C(max). PMID:10962242

  1. Validation of Reference Genes for Relative Quantitative Gene Expression Studies in Cassava (Manihot esculenta Crantz) by Using Quantitative Real-Time PCR

    PubMed Central

    Hu, Meizhen; Hu, Wenbin; Xia, Zhiqiang; Zhou, Xincheng; Wang, Wenquan

    2016-01-01

    Reverse transcription quantitative real-time polymerase chain reaction (real-time PCR, also referred to as quantitative RT-PCR or RT-qPCR) is a highly sensitive and high-throughput method used to study gene expression. Despite the numerous advantages of RT-qPCR, its accuracy is strongly influenced by the stability of internal reference genes used for normalizations. To date, few studies on the identification of reference genes have been performed on cassava (Manihot esculenta Crantz). Therefore, we selected 26 candidate reference genes mainly via the three following channels: reference genes used in previous studies on cassava, the orthologs of the most stable Arabidopsis genes, and the sequences obtained from 32 cassava transcriptome sequence data. Then, we employed ABI 7900 HT and SYBR Green PCR mix to assess the expression of these genes in 21 materials obtained from various cassava samples under different developmental and environmental conditions. The stability of gene expression was analyzed using two statistical algorithms, namely geNorm and NormFinder. geNorm software suggests the combination of cassava4.1_017977 and cassava4.1_006391 as sufficient reference genes for major cassava samples, the union of cassava4.1_014335 and cassava4.1_006884 as best choice for drought stressed samples, and the association of cassava4.1_012496 and cassava4.1_006391 as optimal choice for normally grown samples. NormFinder software recommends cassava4.1_006884 or cassava4.1_006776 as superior reference for qPCR analysis of different materials and organs of drought stressed or normally grown cassava, respectively. Results provide an important resource for cassava reference genes under specific conditions. The limitations of these findings were also discussed. Furthermore, we suggested some strategies that may be used to select candidate reference genes. PMID:27242878

  2. Validation of Reference Genes for Relative Quantitative Gene Expression Studies in Cassava (Manihot esculenta Crantz) by Using Quantitative Real-Time PCR.

    PubMed

    Hu, Meizhen; Hu, Wenbin; Xia, Zhiqiang; Zhou, Xincheng; Wang, Wenquan

    2016-01-01

    Reverse transcription quantitative real-time polymerase chain reaction (real-time PCR, also referred to as quantitative RT-PCR or RT-qPCR) is a highly sensitive and high-throughput method used to study gene expression. Despite the numerous advantages of RT-qPCR, its accuracy is strongly influenced by the stability of internal reference genes used for normalizations. To date, few studies on the identification of reference genes have been performed on cassava (Manihot esculenta Crantz). Therefore, we selected 26 candidate reference genes mainly via the three following channels: reference genes used in previous studies on cassava, the orthologs of the most stable Arabidopsis genes, and the sequences obtained from 32 cassava transcriptome sequence data. Then, we employed ABI 7900 HT and SYBR Green PCR mix to assess the expression of these genes in 21 materials obtained from various cassava samples under different developmental and environmental conditions. The stability of gene expression was analyzed using two statistical algorithms, namely geNorm and NormFinder. geNorm software suggests the combination of cassava4.1_017977 and cassava4.1_006391 as sufficient reference genes for major cassava samples, the union of cassava4.1_014335 and cassava4.1_006884 as best choice for drought stressed samples, and the association of cassava4.1_012496 and cassava4.1_006391 as optimal choice for normally grown samples. NormFinder software recommends cassava4.1_006884 or cassava4.1_006776 as superior reference for qPCR analysis of different materials and organs of drought stressed or normally grown cassava, respectively. Results provide an important resource for cassava reference genes under specific conditions. The limitations of these findings were also discussed. Furthermore, we suggested some strategies that may be used to select candidate reference genes. PMID:27242878

  3. Bibliometric mapping and clustering analysis of Iranian papers on reproductive medicine in Scopus database (2010-2014)

    PubMed Central

    Bazm, Soheila; Kalantar, Seyyed Mehdi; Mirzaei, Masoud

    2016-01-01

    Background: To meet the future challenges in the field of reproductive medicine in Iran, better understanding of published studies is needed. Bibliometric methods and social network analysis have been used to measure the scope and illustrate scientific output of researchers in this field. Objective: This study provides insight into the structure of the network of Iranian papers published in the field of reproductive medicine through 2010-2014. Materials and Methods: In this cross-sectional study, all relevant scientific publications were retrieved from Scopus database and were analyzed according to document type, journal of publication, hot topics, authors and institutions. The results were mapped and clustered by VosViewer software. Results: In total, 3141 papers from Iranian researchers were identified in Scopus database between 2010-2014. The numbers of publications per year have been increased from 461 in 2010 to 749 in 2014. Tehran University of Medical Sciences and "Soleimani M" are occupied the top position based on Productivity indicator. Likewise "Soleimani M" was obtained the first rank among authors according to degree centrality, betweenness centrality and collaboration criteria. In addition, among institutions, Iranian Academic Center for Education, Culture and Research (ACECR) was leader based on degree centrality, betweenness centrality and collaboration indicators. Conclusion: Publications of Iranian researchers in the field of reproductive medicine showed steadily growth during 2010-2014. It seems that in addition to quantity, Iranian authors have to promote quality of articles and collaboration. It will help them to advance their efforts. PMID:27525320

  4. Quantitative In Situ TEM Studies of Small-Scale Plasticity in Irradiated and Unirradiated Metals

    NASA Astrophysics Data System (ADS)

    Chisholm, Claire

    mechanical data, as the two defect conditions exhibit similar yield strengths, ultimate tensile strengths, and number and size of load-drops. This similarity implies that, even if materials contain dissimilar individual defects, the collective defect behavior can result in similar mechanical properties. Thus, the origin of mechanical properties can be ambiguous and caution should be taken when extrapolating to different size scales. Furthermore, such similarities highlight the importance of in-situ observation during deformation. These experiments provide a key test of theory, by providing a local test of behavior, which is much more stringent than testing behaviors averaged over many regions. Advanced electron microscopy imaging techniques and quantitative in-situ TEM tensile tests are performed with Au thin-film as a model FCC structural material. These investigations highlight the various hurdles experimental studies must overcome in order to probe defect behavior at a fundamental level. Two novelly-applied strain mapping techniques are performed to directly measure the matrix strain around helium bubbles in He1+ implanted Au thin-film. Dark-field inline holography (DFIH) is applied here for the first time to a metal, and nano-beam electron diffraction (NBED) transient strain mapping is shown to be experimentally feasible using the high frame rate Gatan K2 camera. The K2 camera reduces scan times from ˜18 minutes to 82 seconds for a 128x256 pixel scan at 400 fps. Both methods measure a peak strain around 10 nm bubbles of 0.7%, correlating to an internal pressure of 580 MPa, or a vacancy to helium ion ratio of 1V:2.4He. Previous studies have relied on determining the appropriate equation of state to relate measured or approximated helium density to internal bubble pressure and thus strain. Direct measurement of the surrounding matrix strain through DFIH and NBED methods effectively bypasses this step, allowing for easier defect interaction modeling as the bubble can be

  5. Reference gene selection for gene expression studies in lily using quantitative real-time PCR.

    PubMed

    Zhang, M F; Liu, Q; Jia, G X

    2016-01-01

    Quantitative real-time polymerase chain reaction (qRT-PCR) is an important technology used to analyze gene-expression levels. Reference genes, which are assumed to be expressed consistently across various developmental stages and in different tissues, were selected for expression level analysis. Using digital gene expression technology, we selected nine reference genes (18S, EF, CYCOL, SAND, GAPDH, ACTIN, BHLH, TIP, and Clathrin) as candidate reference genes for further study. Using three different analysis methods (GeNorm, NormFinder, and BestKeeper), a total of 144 lily (Lilium x formolongi "Raizan 3") samples were analyzed. The samples were collected from four different tissues under various developmental stages. In addition, leaves treated with different plant hormones were collected and analyzed. The data showed that the stability of the nine reference genes differed among samples, but TIP, EF, Clathrin, and BHLH could be identified as the most stable genes overall. In addition, the relative expression level of LfFT in different lily tissues with the competence to flower was also analyzed to verify the selected reference genes. This study constitutes an important source for selecting reference genes when analyzing the expression patterns of flowering time and floral development regulation genes in lily cultivars. PMID:27173307

  6. Quantitative study of impacts of climate change and human activities on runoff in Beiluohe River basin

    NASA Astrophysics Data System (ADS)

    Guo, A.; Huang, Q.; Wang, Y.

    2015-05-01

    In the Beiluohe River basin (BRB) runoff has been experiencing a significant reduction induced by climate change and human activities. This paper considers the impacts of climate change and human activities on runoff reduction. An improved empirical method for climate factors and runoff was developed to study the impacts quantitatively. Meanwhile climate elasticity of runoff, based on the Budyko hypothesis, was also adopted to study the impacts. Using runoff change points, series were divided into natural period (1960-1969) and impacted periods (1970-1994, 1995-2010). Results show that the methods used to quantify the contributions obtained different but close conclusions to one another. For 1970-1994, climate was the primary factor impacting runoff, compared with that for 1960-1969, with the contribution reaching around 70.84-83.42%, which was greater than human activities (16.58-29.16%). For 1995-2010, the role of human activities strengthened with the contribution around 62.58-65.07%, greater than climate changes, around 34.93-37.42%.

  7. A Review of the Statistical and Quantitative Methods Used to Study Alcohol-Attributable Crime

    PubMed Central

    Fitterer, Jessica L.; Nelson, Trisalyn A.

    2015-01-01

    Modelling the relationship between alcohol consumption and crime generates new knowledge for crime prevention strategies. Advances in data, particularly data with spatial and temporal attributes, have led to a growing suite of applied methods for modelling. In support of alcohol and crime researchers we synthesized and critiqued existing methods of spatially and quantitatively modelling the effects of alcohol exposure on crime to aid method selection, and identify new opportunities for analysis strategies. We searched the alcohol-crime literature from 1950 to January 2014. Analyses that statistically evaluated or mapped the association between alcohol and crime were included. For modelling purposes, crime data were most often derived from generalized police reports, aggregated to large spatial units such as census tracts or postal codes, and standardized by residential population data. Sixty-eight of the 90 selected studies included geospatial data of which 48 used cross-sectional datasets. Regression was the prominent modelling choice (n = 78) though dependent on data many variations existed. There are opportunities to improve information for alcohol-attributable crime prevention by using alternative population data to standardize crime rates, sourcing crime information from non-traditional platforms (social media), increasing the number of panel studies, and conducting analysis at the local level (neighbourhood, block, or point). Due to the spatio-temporal advances in crime data, we expect a continued uptake of flexible Bayesian hierarchical modelling, a greater inclusion of spatial-temporal point pattern analysis, and shift toward prospective (forecast) modelling over small areas (e.g., blocks). PMID:26418016

  8. Rationing of nursing care and nurse-patient outcomes: a systematic review of quantitative studies.

    PubMed

    Papastavrou, Evridiki; Andreou, Panayiota; Efstathiou, Georgios

    2014-01-01

    Bedside rationing in nursing care refers to withholding or failure to carry out certain aspects of care because of limited resources such as time, staffing or skill mix. The absence of previous systematic reviews on nursing care rationing leads to a gap of synthesized knowledge on the factors and processes related to rationing and the potential negative consequences on both patients and nurses. The aim of this study was to gain an in-depth understanding of the factors and processes related to nursing care rationing. Selected papers were methodologically assessed based on their design, sampling, measurement and statistical analysis. Seventeen quantitative studies were reviewed, and findings were categorized into four themes: elements of nursing care being rationed, causes of rationing, nurse outcomes and patient outcomes. Results revealed that communication with patients and families, patient ambulation, and mouth care were common elements of rationed care. Nurse-patient workload and communication barriers were reported as potential causes of rationing. Patient-related outcomes included patient falls, nosocomial infections and low patient satisfaction levels. Nurse-related outcomes included low job and occupational satisfaction. In addition, rationing appears to be an important organizational variable linked with patient safety and quality of care. This review increases understanding of what is actually occurring at the point of care delivery so that managers will be able to improve processes that lead to high quality of care and better patient and nurse outcomes. PMID:23296644

  9. Quantitation and pharmacokinetic modeling of therapeutic antibody quality attributes in human studies.

    PubMed

    Li, Yinyin; Monine, Michael; Huang, Yu; Swann, Patrick; Nestorov, Ivan; Lyubarskaya, Yelena

    2016-01-01

    A thorough understanding of drug metabolism and disposition can aid in the assessment of efficacy and safety. However, analytical methods used in pharmacokinetics (PK) studies of protein therapeutics are usually based on ELISA, and therefore can provide a limited perspective on the quality of the drug in concentration measurements. Individual post-translational modifications (PTMs) of protein therapeutics are rarely considered for PK analysis, partly because it is technically difficult to recover and quantify individual protein variants from biological fluids. Meanwhile, PTMs may be directly linked to variations in drug efficacy and safety, and therefore understanding of clearance and metabolism of biopharmaceutical protein variants during clinical studies is an important consideration. To address such challenges, we developed an affinity-purification procedure followed by peptide mapping with mass spectrometric detection, which can profile multiple quality attributes of therapeutic antibodies recovered from patient sera. The obtained data enable quantitative modeling, which allows for simulation of the PK of different individual PTMs or attribute levels in vivo and thus facilitate the assessment of quality attributes impact in vivo. Such information can contribute to the product quality attribute risk assessment during manufacturing process development and inform appropriate process control strategy. PMID:27216574

  10. Extracting Quantitative Measures from EAP: A Small Clinical Study using BFOR

    PubMed Central

    Hosseinbor, A. Pasha; Chung, Moo K.; Wu, Yu-Chien; Fleming, John O.; Field, Aaron S.; Alexander, Andrew L.

    2015-01-01

    The ensemble average propagator (EAP) describes the 3D average diffusion process of water molecules, capturing both its radial and angular contents, and hence providing rich information about complex tissue microstructure properties. Bessel Fourier orientation reconstruction (BFOR) is one of several analytical, non-Cartesian EAP reconstruction schemes employing multiple shell acquisitions that have recently been proposed. Such modeling bases have not yet been fully exploited in the extraction of rotationally invariant q-space indices that describe the degree of diffusion anisotropy/restrictivity. Such quantitative measures include the zero-displacement probability (Po), mean squared displacement (MSD), q-space inverse variance (QIV), and generalized fractional anisotropy (GFA), and all are simply scalar features of the EAP. In this study, a general relationship between MSD and q-space diffusion signal is derived and an EAP-based definition of GFA is introduced. A significant part of the paper is dedicated to utilizing BFOR in a clinical dataset, comprised of 5 multiple sclerosis (MS) patients and 4 healthy controls, to estimate Po, MSD, QIV, and GFA of corpus callosum, and specifically, to see if such indices can detect changes between normal appearing white matter (NAWM) and healthy white matter (WM). Although the sample size is small, this study is a proof of concept that can be extended to larger sample sizes in the future. PMID:23286059

  11. Quantitative study on characteristic parameters of acoustic behavior habits in budgerigars ( Melopsittacus undula fus)

    NASA Astrophysics Data System (ADS)

    Jiang, Jin-Chang; Chen, Hao; Xu, Mu-Ling; Zhang, Hong

    1994-08-01

    On the bases of the studies of acoustic behavior and pattern recognition of budgerigar calls, the quantitative study on characteristic parameters of acoustic behavior habits in budgerigars is further given in this paper. These results open up a new knowledge for comprehensive analyses of abnormalities of acoustic behavior habits in budgerigars prior to earthquakes. Under indoor lighting, the song calls in budgerigars are possessed of the beginning and ending singing time with the natural characteristics, and of the rhythmic habit of daylight singings and night rests. In daily daylight and night calls, single calls, vari-toned calls, mono-syllabic and multi-syllabic protest calls are respectively possessed of the occupation habit corresponding to behavior activities, and have close acrophases and regular following properties corresponding to half-value phases, and the acrophases delay half-value phases by about half an hour on an average. After reversing lighting, the acrophases of budgerigar calls delay those of the normal lighting by about 12 hours on an average, and the following properties corresponding to half-value phases are irregular.

  12. Quantitative analysis and efficiency study of PSD methods for a LaBr3:Ce detector

    NASA Astrophysics Data System (ADS)

    Zeng, Ming; Cang, Jirong; Zeng, Zhi; Yue, Xiaoguang; Cheng, Jianping; Liu, Yinong; Ma, Hao; Li, Junli

    2016-03-01

    The LaBr3:Ce scintillator has been widely studied for nuclear spectroscopy because of its optimal energy resolution (<3%@ 662 keV) and time resolution (~300 ps). Despite these promising properties, the intrinsic radiation background of LaBr3:Ce is a critical issue, and pulse shape discrimination (PSD) has been shown to be an efficient potential method to suppress the alpha background from the 227Ac. In this paper, the charge comparison method (CCM) for alpha and gamma discrimination in LaBr3:Ce is quantitatively analysed and compared with two other typical PSD methods using digital pulse processing. The algorithm parameters and discrimination efficiency are calculated for each method. Moreover, for the CCM, the correlation between the CCM feature value distribution and the total charge (energy) is studied, and a fitting equation for the correlation is inferred and experimentally verified. Using the equations, an energy-dependent threshold can be chosen to optimize the discrimination efficiency. Additionally, the experimental results show a potential application in low-activity high-energy γ measurement by suppressing the alpha background.

  13. Photobacterium profundum under Pressure: A MS-Based Label-Free Quantitative Proteomics Study

    PubMed Central

    Le Bihan, Thierry; Rayner, Joe; Roy, Marcia M.; Spagnolo, Laura

    2013-01-01

    Photobacterium profundum SS9 is a Gram-negative bacterium, originally collected from the Sulu Sea. Its genome consists of two chromosomes and a 80 kb plasmid. Although it can grow under a wide range of pressures, P. profundum grows optimally at 28 MPa and 15°C. Its ability to grow at atmospheric pressure allows for both easy genetic manipulation and culture, making it a model organism to study piezophily. Here, we report a shotgun proteomic analysis of P. profundum grown at atmospheric compared to high pressure using label-free quantitation and mass spectrometry analysis. We have identified differentially expressed proteins involved in high pressure adaptation, which have been previously reported using other methods. Proteins involved in key metabolic pathways were also identified as being differentially expressed. Proteins involved in the glycolysis/gluconeogenesis pathway were up-regulated at high pressure. Conversely, several proteins involved in the oxidative phosphorylation pathway were up-regulated at atmospheric pressure. Some of the proteins that were differentially identified are regulated directly in response to the physical impact of pressure. The expression of some proteins involved in nutrient transport or assimilation, are likely to be directly regulated by pressure. In a natural environment, different hydrostatic pressures represent distinct ecosystems with their own particular nutrient limitations and abundances. However, the only variable considered in this study was atmospheric pressure. PMID:23741291

  14. Career interest, self-efficacy, and perception in undecided and nursing undergraduate students: a quantitative study.

    PubMed

    Fillman, Valentina M

    2015-01-01

    Career choice variables of career interest, self-efficacy, and perception were chosen based upon Social Cognitive Career Theory concepts for study between nursing and undecided undergraduate student groups. Components of the Career Search Questionnaire and Perceptions of Professional Nursing instruments were combined and adapted to form the Career Choice Survey for use in this research. This web-based survey totaling 40 questions was sent to 577 undergraduate students with a 12% response rate (N=68). Due to the need to increase nursing recruitment and retention, hypotheses were developed that distinguish if any relationship existed between groups. Findings of this quantitative study resulted in statistically significant results on two of the three variable hypotheses (p=.006 for career interest, p=.002 for self-efficacy, p=.395 for perception), aligning with previous research and provide insight into the change in nursing perception. Overall, scores for each subscale were encouraging to current nurses and expected from undecided students. Implications for practice include increases in accurate nursing portrayal in the media and early career counseling to younger populations. Nurse educators can further research in career choice with focus on continuing education for current nurses and recruitment of young nursing hopefuls. PMID:25218036

  15. Quantitation and pharmacokinetic modeling of therapeutic antibody quality attributes in human studies

    PubMed Central

    Li, Yinyin; Monine, Michael; Huang, Yu; Swann, Patrick; Nestorov, Ivan; Lyubarskaya, Yelena

    2016-01-01

    ABSTRACT A thorough understanding of drug metabolism and disposition can aid in the assessment of efficacy and safety. However, analytical methods used in pharmacokinetics (PK) studies of protein therapeutics are usually based on ELISA, and therefore can provide a limited perspective on the quality of the drug in concentration measurements. Individual post-translational modifications (PTMs) of protein therapeutics are rarely considered for PK analysis, partly because it is technically difficult to recover and quantify individual protein variants from biological fluids. Meanwhile, PTMs may be directly linked to variations in drug efficacy and safety, and therefore understanding of clearance and metabolism of biopharmaceutical protein variants during clinical studies is an important consideration. To address such challenges, we developed an affinity-purification procedure followed by peptide mapping with mass spectrometric detection, which can profile multiple quality attributes of therapeutic antibodies recovered from patient sera. The obtained data enable quantitative modeling, which allows for simulation of the PK of different individual PTMs or attribute levels in vivo and thus facilitate the assessment of quality attributes impact in vivo. Such information can contribute to the product quality attribute risk assessment during manufacturing process development and inform appropriate process control strategy. PMID:27216574

  16. Quantitative and qualitative processes of change during staff-coaching sessions: an exploratory study.

    PubMed

    van Oorsouw, Wietske M W J; Embregts, Petri J C M; Bosman, Anna M T

    2013-05-01

    Staff training is one of the interventions that managers can embed in their organizations to help staff improve their professional competences related to challenging behaviour of clients with intellectual disabilities. Individual coaching adds learning opportunities that are feasible but difficult to achieve in an in-service setting. In the present study, we have followed the coaching process of three staff members. Based on differences in the Linell balance of power across sessions, we explored the question: do different coaching processes have similar patterns in the development of dominance and coherence in interactions between coach and staff? Additionally, a qualitative approach was conducted to illustrate and enrich the meaning of quantitative outcomes. Processes were different regarding the balance of power at the start of the coaching, probably due to differences in resistance and insecurity. As a consequence of different starting points and differences in learning styles, each coaching process had its unique development over time. At the end, all dyads were comparable in the sense that all dyads were highly satisfied about the outcomes and process of coaching. This is in line with similar levels of power at the end of the coaching sessions suggesting equal contributions and leadership. The present findings suggest some relevant competencies of coaches within health-care services. Due to the small number of participants, the results have to be interpreted with caution. The present study provides suggestions for future research and clinical practice. PMID:23474998

  17. Quantitative methods for reconstructing tissue biomechanical properties in optical coherence elastography: a comparison study

    PubMed Central

    Han, Zhaolong; Li, Jiasong; Singh, Manmohan; Wu, Chen; Liu, Chih-hao; Wang, Shang; Idugboe, Rita; Raghunathan, Raksha; Sudheendran, Narendran; Aglyamov, Salavat R.; Twa, Michael D.; Larin, Kirill V.

    2015-01-01

    We present a systematic analysis of the accuracy of five different methods for extracting the biomechanical properties of soft samples using optical coherence elastography (OCE). OCE is an emerging noninvasive technique, which allows assessing biomechanical properties of tissues with a micrometer spatial resolution. However, in order to accurately extract biomechanical properties from OCE measurements, application of proper mechanical model is required. In this study, we utilize tissue-mimicking phantoms with controlled elastic properties and investigate the feasibilities of four available methods for reconstructing elasticity (Young’s modulus) based on OCE measurements of an air-pulse induced elastic wave. The approaches are based on the shear wave equation (SWE), the surface wave equation (SuWE), Rayleigh-Lamb frequency equation (RLFE), and finite element method (FEM), Elasticity values were compared with uniaxial mechanical testing. The results show that the RLFE and the FEM are more robust in quantitatively assessing elasticity than the other simplified models. This study provides a foundation and reference for reconstructing the biomechanical properties of tissues from OCE data, which is important for the further development of noninvasive elastography methods. PMID:25860076

  18. Quantitative neuroproteomics: classical and novel tools for studying neural differentiation and function.

    PubMed

    Colucci-D'Amato, Luca; Farina, Annarita; Vissers, Johannes P C; Chambery, Angela

    2011-03-01

    Mechanisms underlying neural stem cell proliferation, differentiation and maturation play a critical role in the formation and wiring of neuronal connections. This process involves the activation of multiple serial events, which guide the undifferentiated cells to different lineages via distinctive developmental programs, forming neuronal circuits and thus shaping the adult nervous system. Furthermore, alterations within these strictly regulated pathways can lead to severe neurological and psychiatric diseases. In this framework, the investigation of the high dynamic protein expression changes and other factors affecting protein functions, for example post-translational modifications, the alterations of protein interaction networks, is of pivotal importance for the understanding of the molecular mechanisms responsible for cell differentiation. More recently, proteomic studies in neuroscience ("neuroproteomics") are receiving increased interest for the primary understanding of the regulatory networks underlying neuronal differentiation processes. Besides the classical two-dimensional-based proteomic strategies, the emerging platforms for LC-MS shotgun proteomic analysis hold great promise in unraveling the molecular basis of neural stem cell differentiation. In this review, recent advancements in label-free LC-MS quantitative neuroproteomics are highlighted as a new tool for the study of neural differentiation and functions, in comparison to mass spectrometry-based labeling approaches. The more commonly used protein profiling strategies and model systems for the analysis of neural differentiation are also discussed, along with the challenging proteomic approaches aimed to analyze the nervous system-specific organelles, the neural cells secretome and the specific protein interaction networks. PMID:20352529

  19. A Comparative Study on Tobacco Cessation Methods: A Quantitative Systematic Review

    PubMed Central

    Heydari, Gholamreza; Masjedi, Mohammadreza; Ahmady, Arezoo Ebn; Leischow, Scott J.; Lando, Harry A.; Shadmehr, Mohammad Behgam; Fadaizadeh, Lida

    2014-01-01

    Background: During recent years, there have been many advances in different types of pharmacological and non-pharmacological tobacco control treatments. In this study, we aimed to identify the most effective smoking cessation methods used in quit based upon a review of the literature. Methods: We did a search of PubMed, limited to English publications from 2000 to 2012. Two trained reviewers independently assessed titles, abstracts and full texts of articles after a pilot inter-rater reliability assessment which was conducted by the author (GH). The total number of papers and their conclusions including recommendation of that method (positive) or not supporting (negative) was computed for each method. The number of negative papers was subtracted from the number of positive ones for each method. In cases of inconsistency between the two reviewers, these were adjudicated by author. Results: Of the 932 articles that were critically assessed, 780 studies supported quit smoking methods. In 90 studies, the methods were not supported or rejected and in 62 cases the methods were not supported. Nicotine replacement therapy (NRT), Champix and Zyban with 352, 117 and 71 studies respectively were the most supported methods and e-cigarettes and non-Nicotine medications with one case were the least supported methods. Finally, NRT with 39 and Champix and education with 36 scores were the most supported methods. Conclusions: Results of this review indicate that the scientific papers in the most recent decade recommend the use of NRT and Champix in combination with educational interventions. Additional research is needed to compare qualitative and quantitative studies for smoking cessation. PMID:25013685

  20. Chronic spinal compression model in minipigs: a systematic behavioral, qualitative, and quantitative neuropathological study.

    PubMed

    Navarro, Roman; Juhas, Stefan; Keshavarzi, Sassan; Juhasova, Jana; Motlik, Jan; Johe, Karl; Marsala, Silvia; Scadeng, Miriam; Lazar, Peter; Tomori, Zoltan; Schulteis, Gery; Beattie, Michael; Ciacci, Joseph D; Marsala, Martin

    2012-02-10

    The goal of the present study was to develop a porcine spinal cord injury (SCI) model, and to describe the neurological outcome and characterize the corresponding quantitative and qualitative histological changes at 4-9 months after injury. Adult Gottingen-Minnesota minipigs were anesthetized and placed in a spine immobilization frame. The exposed T12 spinal segment was compressed in a dorso-ventral direction using a 5-mm-diameter circular bar with a progressively increasing peak force (1.5, 2.0, or 2.5 kg) at a velocity of 3 cm/sec. During recovery, motor and sensory function were periodically monitored. After survival, the animals were perfusion fixed and the extent of local SCI was analyzed by (1) post-mortem MRI analysis of dissected spinal cords, (2) qualitative and quantitative analysis of axonal survival at the epicenter of injury, and (3) defining the presence of local inflammatory changes, astrocytosis, and schwannosis. Following 2.5-kg spinal cord compression the animals demonstrated a near complete loss of motor and sensory function with no recovery over the next 4-9 months. Those that underwent spinal cord compression with 2 kg force developed an incomplete injury with progressive partial neurological recovery characterized by a restricted ability to stand and walk. Animals injured with a spinal compression force of 1.5 kg showed near normal ambulation 10 days after injury. In fully paralyzed animals (2.5 kg), MRI analysis demonstrated a loss of spinal white matter integrity and extensive septal cavitations. A significant correlation between the magnitude of loss of small and medium-sized myelinated axons in the ventral funiculus and neurological deficits was identified. These data, demonstrating stable neurological deficits in severely injured animals, similarities of spinal pathology to humans, and relatively good post-injury tolerance of this strain of minipigs to spinal trauma, suggest that this model can successfully be used to study

  1. QUANTITATIVE COMPARISON OF MOLECULAR ELECTROSTATIC POTENTIALS FOR STRUCTURE-ACTIVITY STUDIES

    EPA Science Inventory

    Further development of an approach for representing, efficiently calculating and comparing discreet 3-dimensional molecular electrostatic potentials using a quantitative similarity index (MEP-SI) based on the Carbo formalism is presented. adial-type (MACRA) grid representation is...

  2. Compatibility of Qualitative and Quantitative Methods: Studying Child Sexual Abuse in America.

    ERIC Educational Resources Information Center

    Phelan, Patricia

    1987-01-01

    Illustrates how the combined use of qualitative and quantitative methods were necessary in obtaining a clearer understanding of the process of incest in American society. Argues that the exclusive use of one methodology would have obscured important information. (FMW)

  3. Correction for FDG PET dose extravasations: Monte Carlo validation and quantitative evaluation of patient studies

    SciTech Connect

    Silva-Rodríguez, Jesús Aguiar, Pablo; Sánchez, Manuel; Mosquera, Javier; Luna-Vega, Víctor; Cortés, Julia; Garrido, Miguel; Pombar, Miguel; Ruibal, Álvaro

    2014-05-15

    Purpose: Current procedure guidelines for whole body [18F]fluoro-2-deoxy-D-glucose (FDG)-positron emission tomography (PET) state that studies with visible dose extravasations should be rejected for quantification protocols. Our work is focused on the development and validation of methods for estimating extravasated doses in order to correct standard uptake value (SUV) values for this effect in clinical routine. Methods: One thousand three hundred sixty-seven consecutive whole body FDG-PET studies were visually inspected looking for extravasation cases. Two methods for estimating the extravasated dose were proposed and validated in different scenarios using Monte Carlo simulations. All visible extravasations were retrospectively evaluated using a manual ROI based method. In addition, the 50 patients with higher extravasated doses were also evaluated using a threshold-based method. Results: Simulation studies showed that the proposed methods for estimating extravasated doses allow us to compensate the impact of extravasations on SUV values with an error below 5%. The quantitative evaluation of patient studies revealed that paravenous injection is a relatively frequent effect (18%) with a small fraction of patients presenting considerable extravasations ranging from 1% to a maximum of 22% of the injected dose. A criterion based on the extravasated volume and maximum concentration was established in order to identify this fraction of patients that might be corrected for paravenous injection effect. Conclusions: The authors propose the use of a manual ROI based method for estimating the effectively administered FDG dose and then correct SUV quantification in those patients fulfilling the proposed criterion.

  4. Genetic Studies of Quantitative MCI and AD Phenotypes in ADNI: Progress, Opportunities, and Plans

    PubMed Central

    Saykin, Andrew J.; Shen, Li; Yao, Xiaohui; Kim, Sungeun; Nho, Kwangsik; Risacher, Shannon L.; Ramanan, Vijay K.; Foroud, Tatiana M.; Faber, Kelly M.; Sarwar, Nadeem; Munsie, Leanne M.; Hu, Xiaolan; Soares, Holly D.; Potkin, Steven G.; Thompson, Paul M.; Kauwe, John S.K.; Kaddurah-Daouk, Rima; Green, Robert C.; Toga, Arthur W.; Weiner, Michael W.

    2015-01-01

    INTRODUCTION Genetic data from the Alzheimer’s Disease Neuroimaging Initiative (ADNI) has been crucial in advancing the understanding of AD pathophysiology. Here we provide an update on sample collection, scientific progress and opportunities, conceptual issues, and future plans. METHODS Lymphoblastoid cell lines and DNA and RNA samples from blood have been collected and banked, and data and biosamples have been widely disseminated. To date, APOE genotyping, genome-wide association study (GWAS), and whole exome and whole genome sequencing (WES, WGS) data have been obtained and disseminated. RESULTS ADNI genetic data have been downloaded thousands of times and over 300 publications have resulted, including reports of large scale GWAS by consortia to which ADNI contributed. Many of the first applications of quantitative endophenotype association studies employed ADNI data, including some of the earliest GWAS and pathway-based studies of biospecimen and imaging biomarkers, as well as memory and other clinical/cognitive variables. Other contributions include some of the first WES and WGS data sets and reports in healthy controls, MCI, and AD. DISCUSSION Numerous genetic susceptibility and protective markers for AD and disease biomarkers have been identified and replicated using ADNI data, and have heavily implicated immune, mitochondrial, cell cycle/fate, and other biological processes. Early sequencing studies suggest that rare and structural variants are likely to account for significant additional phenotypic variation. Longitudinal analyses of transcriptomic, proteomic, metabolomic, and epigenomic changes will also further elucidate dynamic processes underlying preclinical and prodromal stages of disease. Integration of this unique collection of multi-omics data within a systems biology framework will help to separate truly informative markers of early disease mechanisms and potential novel therapeutic targets from the vast background of less relevant biological

  5. A comprehensive categorical and bibliometric analysis of published research articles on pediatric pain from 1975 to 2010.

    PubMed

    Caes, Line; Boerner, Katelynn E; Chambers, Christine T; Campbell-Yeo, Marsha; Stinson, Jennifer; Birnie, Kathryn A; Parker, Jennifer A; Huguet, Anna; Jordan, Abbie; MacLaren Chorney, Jill; Schinkel, Meghan; Dol, Justine

    2016-02-01

    The field of pediatric pain research began in the mid-1970s and has undergone significant growth and development in recent years as evidenced by the variety of books, conferences, and journals on the topic and also the number of disciplines engaged in work in this area. Using categorical and bibliometric meta-trend analysis, this study offers a synthesis of research on pediatric pain published between 1975 and 2010 in peer-reviewed journals. Abstracts from 4256 articles, retrieved from Web of Science, were coded across 4 categories: article type, article topic, type and age of participants, and pain stimulus. The affiliation of the first author and number of citations were also gathered. The results suggest a significant increase in the number of publications over the time period investigated, with 96% of the included articles published since 1990 and most research being multiauthored publications in pain-focused journals. First authors were most often from the United States and affiliated with a medical department. Most studies were original research articles; the most frequent topics were pain characterization (39.86%), pain intervention (37.49%), and pain assessment (25.00%). Clinical samples were most frequent, with participants most often characterized as children (6-12 years) or adolescents (13-18 years) experiencing chronic or acute pain. The findings provide a comprehensive overview of contributions in the field of pediatric pain research over 35 years and offers recommendations for future research in the area. PMID:26529270

  6. A Quantitative Study of Teacher Readiness to Teach School-Based HIV/AIDS Education in Kenyan Primary Schools

    ERIC Educational Resources Information Center

    Lang'at, Edwin K.

    2014-01-01

    Purpose and Method of Study: The purpose of this study was to investigate teachers' self-perceived readiness to teach school-based HIV/AIDS Awareness and Prevention education in Kenyan primary schools based on their knowledge, attitudes and instructional confidence. This research utilized a non-experimental quantitative approach with a…

  7. Is It Science? A Study of the Attitudes of Medical Trainees and Physicians toward Qualitative and Quantitative Research

    ERIC Educational Resources Information Center

    Goguen, Jeannette; Knight, Melanie; Tiberius, Richard

    2008-01-01

    This study examined the degree of acceptance of qualitative research by medical trainees and physicians, and explored the causes for any differences in their support of qualitative versus quantitative research. Thirty-two individuals at four levels of medical training were studied. Eight philosophers of science served for construct validation.…

  8. The Relationship between Shyness and Internet Addiction: A Quantitative Study on Middle and Post Secondary School Students

    ERIC Educational Resources Information Center

    Hollingsworth, W. Craig

    2005-01-01

    This small scale quantitative study looks into the relationship between shyness and internet addiction in middle school students. This study has been conducted on the belief that shyness is a possible predictor of Internet Addiction. To prove this hypothesis a questionnaire was created and distributed to 53 middle school students and 159 post…

  9. Mapping the history and current situation of research on John Cunningham virus – a bibliometric analysis

    PubMed Central

    2009-01-01

    Background John Cunningham virus (JCV) constitutes a family of polyoma viruses, which plays important roles in the progressive multifocal leukoencephalopathy (PML) and tumorigenesis. However, no bibliometric investigation has been reported to guide the researchers and potential readers. Methods Papers were collected from database Sci-expanded and Pubmed until May 22, 2008. The highly-productive authors, institutes and countries, highly-cited authors and journals were ranked. The highly-cited articles were subjected to co-citation and chronological analysis with highly-frequent MeSH words for co-occurrence analysis. Results Until now, 1785 articles about JCV were indexed in Sci-expanded and 1506 in Pubmed. The main document type was original article. USA, Japan and Italy were the largest three producers about JCV. Temple University published 128 papers and ranked the top, followed by University of Tokyo. Khalili K and Yogo Y became the core authors due to more than 20 documents produced. Journal of Neurovirology published more than 15 papers and ranked the top. Padgett BL and Berger JR were the first two highly-cited authors. Journal of Virology and Journal of Neurovirology respectively ranked to the first two highly-cited journals. These top highly-cited articles were divided into 5 aspects: (1) The correlation between JC virus and tumors; (2) Causal correlation of JCV with PML; (3) Polyoma virus infection and its related diseases in renal-allograft recipients; (4) Detection of JCV antibody, oncogene and its encoding protein; (5) Genetics and molecular biology of JCV. The MeSH/subheadings were classified into five groups: (1) JCV and virus infectious diseases; (2) JCV pathogenicity and pathological appearance of PML; (3) JCV isolation and detection; (4) Immunology of JCV and PML; (5) JCV genetics and tumors. Conclusion JCV investigation mainly focused on its isolation and detection, as well as its correlation with PML and tumors. Establishment of transgenic animal

  10. Effects of Anti-Human Neutrophil Antibodies In Vitro. QUANTITATIVE STUDIES

    PubMed Central

    Boxer, Laurence A.; Stossel, Thomas P.

    1974-01-01

    Opsonic, antiphagocytic, cytotoxic, and metabolic effects of homologous and heterologous antibodies against human neutrophils were analyzed by means of quantitative assays to facilitate detection of antibody activity, and to probe membrane function of these cells. Normal human neutrophils were purified by gradient centrifugation, sensitized with heat-inactivated antineutrophil antisera, and incubated with rabbit alveolar macrophages in balanced salt solution containing nitroblue tetrazolium. The macrophages engulfed sensitized neutrophils and reduced nitroblue tetrazolium to formazan in phagocytic vacuoles. The initial rate of nitroblue tetrazolium reduction by macrophages ingesting the neutrophils was measured spectrophotometrically. Neutrophils treated with rabbit anti-human leukocyte antiserum or IgG, with sera from mothers of infants with neonatal isoimmune neutropenia, and with 27% of sera from frequently transfused patients promoted rapid rates of nitroblue tetrazolium reduction by alveolar macrophages. This indicates that antineutrophil antibodies without added complement opsonized neutrophils for ingestion by the macrophages. Some sera from frequently transfused patients with opsonic activity for certain donors' neutrophils did not agglutinate these neutrophils (44%), did not lyse them in the presence of fresh plasma (47%), and did not inhibit phagocytosis of particles by the neutrophils (26%). The reverse was not observed. The opsonic activity of antineutrophil antiserum appears to be the most sensitive and a quantitative means of detecting antibody activity in vitro. Low concentrations of rabbit anti-human leukocyte antisera or IgG stimulated the ingestion rate of unopsonized or opsonized particles by human neutrophils, and, as previously reported by others, enhanced rates of oxidation of [1-14C]glucose by the cells. High concentrations of the antisera or IgG inhibited ingestion. All concentrations of homologous antineutrophil antisera tested only

  11. The quantitative analysis of OH in vesuvianite: a polarized FTIR and SIMS study

    NASA Astrophysics Data System (ADS)

    Bellatreccia, Fabio; della Ventura, Giancarlo; Ottolini, Luisa; Libowitzky, Eugen; Beran, Anton

    2005-05-01

    A well-characterized suite of vesuvianite samples from the volcanic ejecta (skarn or syenites) from Latium (Italy) was studied by single-crystal, polarized radiation, Fourier-transform infrared (FTIR) spectroscopy and secondary-ion mass-spectrometry (SIMS). OH-stretching FTIR spectra consist of a rather well-defined triplet of broad bands at higher-frequency (3,700 3,300 cm-1) and a very broad composite absorption below 3,300 cm-1. Measurements with E//c or E⊥c show that all bands are strongly polarized with maximum absorption for E//c. They are in agreement with previous band assignments (Groat et al. Can Mineral 33:609, 1995) to the two O(11) H(1) and O(10) H(2) groups in the structure. Pleochroic measurements with changing direction of the E vector of the incident radiation show that the orientation of the O(11) H(1) dipole is OH∧c~35°, in excellent agreement with the neutron data of Lager et al. (Can Mineral 37:763, 1999). A SIMS-based calibration curve at ~10% rel. accuracy has been worked out and used as reference for the quantitative analysis of H2O in vesuvianite by FTIR. Based on previous SIMS results for silicate minerals (Ottolini and Hawthorne in J Anal At Spectrom 16:1266, 2001; Ottolini et al. in Am Mineral 87:1477, 2002) the SiO2 and FeO content of the matrix were assumed as the major factors to be considered at a first approximation in the selection of the standards for H. The lack of vesuvianite standards for quantitative SIMS analysis of H2O has been here overcome by selecting low-silica elbaite crystals (Ottolini et al. in Am Mineral 87:1477, 2002). The resulting integrated molar absorption FTIR coefficient for vesuvianite is ɛi=100.000±2.000 l mol-1 cm-2. SIMS data for Li, B, F, Sr, Y, Be, Ba REE, U and Th are also provided in the paper.

  12. Keratin intermediate filament structure. Crosslinking studies yield quantitative information on molecular dimensions and mechanism of assembly.

    PubMed

    Steinert, P M; Marekov, L N; Fraser, R D; Parry, D A

    1993-03-20

    One of the major obstacles to solving the full three-dimensional structure of keratin intermediate filaments (KIF) is the determination of the exact mode(s) of alignment of nearest-neighbor molecules; this in turn requires precise information of the lengths of the non-alpha-helical linker segments within the coiled-coil alpha-helical heterodimer molecule. In this study, we have induced lysine-lysine and cysteine-cysteine crosslinks between keratin intermediate filament molecules in small assembly-competent oligomers, isolated them and then characterized the natures and locations of the crosslinks. Of more than 100 found, 21 quantitatively major crosslinks were used to obtain the relative axial alignments of rod domain segments by least-squares fitting methods. Three dominant modes of alignment were found. In each case the molecules are antiparallel with the first involving molecules in approximate register (stagger = -0.2 nm), the second involving molecules staggered so as to bring the 1B segments into approximate alignment (stagger = -16.1 nm), and the third involving molecules staggered so as to bring the 2B segments into approximate alignment (stagger = 28.2 nm). In addition, the data enable quantitative estimates to be made for the first time of the lengths of the non-coiled-coil segments (L1 = 2.5 nm, L12 = 1.6 nm, L2 = 0.8 nm), and the total length of the rod domain (46.0 nm). Alignment of molecules according to these parameters permits construction of a two-dimensional surface lattice which displays a 1.6 nm (10 or 11 residue) overlap between similarly directed molecules. Together, the data predict six important overlapping sequence regions that recur about 16 times per 46 nm of filament length. Interestingly, synthetic peptides corresponding to these sequences, singly or in combination, significantly interfere with keratin filament structural integrity. These results thus represent the most significant set of structural constraints for KIF yet available and

  13. Quantitative study on experimentally observed poroelastic behavior of Berea sandstone in two-phase fluid system

    NASA Astrophysics Data System (ADS)

    Goto, Hiroki; Aichi, Masaatsu; Tokunaga, Tomochika; Yamamoto, Hajime; Ogawa, Toyokazu; Aoki, Tomoyuki

    2014-08-01

    Coupled two-phase fluid flow and poroelastic deformation of Berea sandstone is studied through laboratory experiment and numerical simulation. In the experiment, compressed air was infiltrated from the bottom of a water-saturated cylindrical Berea sandstone sample under hydrostatic external stress condition. Both axial and circumferential strains at half the height of the sample showed sudden extension and monotonic and gradual extension afterward. Numerical simulation based on thermodynamically consistent constitutive equations was conducted in order to quantitatively analyze the experimental results. In a simulation assuming isotropy of material properties, the volumetric discharge rate of water at the outlet and one of the axial, circumferential, and volumetric strains at half the height of the sample were reproduced well by each parameter set, while the other two strains were not. When introducing transverse isotropy, all the experimental data were reproduced well. In addition, the effect of saturation dependency of Bishop's effective stress coefficient on the deformation behavior of porous media was discussed, and it was found that strains, both axial and circumferential, are sensitive to the coefficient.

  14. Qualitative, quantitative and temporal study of cutting agents for cocaine and heroin over 9 years.

    PubMed

    Broséus, Julian; Gentile, Natacha; Bonadio Pont, Federica; Garcia Gongora, Juan Manuel; Gasté, Laëtitia; Esseiva, Pierre

    2015-12-01

    Forensic laboratories mainly focus on the qualification and the quantitation of the illicit drug under analysis as both aspects are used for judiciary purposes. Therefore, information related to cutting agents (adulterants and diluents) detected in illicit drugs is limited in the forensic literature. This article discusses the type and frequency of adulterants and diluents detected in more than 6000 cocaine specimens and 3000 heroin specimens, confiscated in western Switzerland from 2006 to 2014. The results show a homogeneous and quite unchanging adulteration for heroin, while for cocaine it could be characterised as heterogeneous and relatively dynamic. Furthermore, the results indicate that dilution affects more cocaine than heroin. Therefore, the results provided by this study tend to reveal differences between the respective structures of production or distribution of cocaine and heroin. This research seeks to promote the systematic analysis of cutting agents by forensic laboratories. Collecting and processing data related to the presence of cutting agents in illicit drug specimens produces relevant information to understand and to compare the structure of illicit drug markets. PMID:26448535

  15. Quantitative study of Helicobacter pylori in gastric mucus by competitive PCR using synthetic DNA fragments.

    PubMed Central

    Furuta, T; Kaneko, E; Suzuki, M; Arai, H; Futami, H

    1996-01-01

    Helicobacter pylori is closely related to upper gastrointestinal diseases, and the precise evaluation of H. pylori infection is necessary for the treatment of these diseases. The aim of the present study was to establish a method for the quantitative detection of H. pylori. We applied a competitive PCR method using various amounts of synthetic DNA fragments containing the same primer-binding and a subset of the same template sequences as the target competing for primer binding and amplification in order to quantify H. pylori in gastric mucus. The results obtained by this method were compared with the results of histological examination, the rapid urease test, bacterial culture, the [13C]urea breath test, and urea and ammonia measurements in gastric juice. As the quantity of H. pylori in gastric mucus increased, the rates of positivity of histological examination, the rapid urease test, and bacterial culture increased. The quantity of H. pylori in gastric mucus was also significantly correlated with the results of the [13C]urea breath test and was negatively correlated with the urea/ammonia ratio in gastric juice. The competitive PCR method provides an objective measure of the quantity of H. pylori and makes it possible to distinguish true negatives from false negatives due to incomplete PCR and true positives from false positives due to contamination. This method is very useful for the precise evaluation of gastric H. pylori infection. PMID:8880492

  16. Contribution of insula in Parkinson's disease: A quantitative meta-analysis study.

    PubMed

    Criaud, Marion; Christopher, Leigh; Boulinguez, Philippe; Ballanger, Benedicte; Lang, Anthony E; Cho, Sang S; Houle, Sylvain; Strafella, Antonio P

    2016-04-01

    The insula region is known to be an integrating hub interacting with multiple brain networks involved in cognitive, affective, sensory, and autonomic processes. There is growing evidence suggesting that this region may have an important role in Parkinson's disease (PD). Thus, to investigate the functional organization of the insular cortex and its potential role in parkinsonian features, we used a coordinate-based quantitative meta-analysis approach, the activation likelihood estimation. A total of 132 insular foci were selected from 96 published experiments comprising the five functional categories: cognition, affective/behavioral symptoms, bodily awareness/autonomic function, sensorimotor function, and nonspecific resting functional changes associated with the disease. We found a significant convergence of activation maxima related to PD in different insular regions including anterior and posterior regions bilaterally. This study provides evidence of an important functional distribution of different domains within the insular cortex in PD, particularly in relation to nonmotor aspects, with an influence of medication effect. Hum Brain Mapp 37:1375-1392, 2016. © 2016 Wiley Periodicals, Inc. PMID:26800238

  17. A comparative study of quantitative stains for DNA in image cytometry.

    PubMed

    Mikel, U V; Becker, R L

    1991-08-01

    In this study we examined the reproducibility of several stains used to measure nuclear DNA by image cytometry. The specimens were touch preparations of liver and testis from mouse and liver, intestine and brain from rat, fixed in either neutral formalin or Carnoy's solution. The tested stains included four Feulgen methods (pararosaniline, azure-A, thionin and acriflavine), the gallocyanine-chromalum stain and two fluorescent stains (acridine orange and propidium iodide). Absorbance measurements employed a video image analysis system; fluorescence measurements were from a scanning microspectrophotometer. The acriflavine-Feulgen stain was analyzed for both absorbance and fluorescence. All seven stains were quantitative for DNA and gave reproducible results. The absorbance measurements had a lower coefficient of variation (CV) than the fluorescence values. In a nested analysis of variance of the pararosaniline Feulgen stains, cell-to-cell variability accounted for 67% of the total variance; slide-to-slide, 9%; and batch-to-batch, 24%. These values did not change significantly when the staining was performed in an automatic staining machine. For DNA analysis using image cytometry, we conclude that the Feulgen staining technique is the most useful. In particular, acriflavine-Feulgen-stained cells fixed in Carnoy's fluid give the least variation between measurement values and the most accurate ratios between the separate ploidy groups. For fluorescence cytometry we recommend Carnoy's fixation and the acriflavine-Feulgen stain because of its narrow CV as compared to acridine orange and propidium iodide. PMID:1718295

  18. Development of quantitative atomic modeling for tungsten transport study using LHD plasma with tungsten pellet injection

    NASA Astrophysics Data System (ADS)

    Murakami, I.; Sakaue, H. A.; Suzuki, C.; Kato, D.; Goto, M.; Tamura, N.; Sudo, S.; Morita, S.

    2015-09-01

    Quantitative tungsten study with reliable atomic modeling is important for successful achievement of ITER and fusion reactors. We have developed tungsten atomic modeling for understanding the tungsten behavior in fusion plasmas. The modeling is applied to the analysis of tungsten spectra observed from plasmas of the large helical device (LHD) with tungsten pellet injection. We found that extreme ultraviolet (EUV) emission of W24+ to W33+ ions at 1.5-3.5 nm are sensitive to electron temperature and useful to examine the tungsten behavior in edge plasmas. We can reproduce measured EUV spectra at 1.5-3.5 nm by calculated spectra with the tungsten atomic model and obtain charge state distributions of tungsten ions in LHD plasmas at different temperatures around 1 keV. Our model is applied to calculate the unresolved transition array (UTA) seen at 4.5-7 nm tungsten spectra. We analyze the effect of configuration interaction on population kinetics related to the UTA structure in detail and find the importance of two-electron-one-photon transitions between 4p54dn+1- 4p64dn-14f. Radiation power rate of tungsten due to line emissions is also estimated with the model and is consistent with other models within factor 2.

  19. Dietary lipids and blood cholesterol: quantitative meta-analysis of metabolic ward studies.

    PubMed Central

    Clarke, R.; Frost, C.; Collins, R.; Appleby, P.; Peto, R.

    1997-01-01

    OBJECTIVE: To determine the quantitative importance of dietary fatty acids and dietary cholesterol to blood concentrations of total, low density lipoprotein, and high density lipoprotein cholesterol. DESIGN: Meta-analysis of metabolic ward studies of solid food diets in healthy volunteers. SUBJECTS: 395 dietary experiments (median duration 1 month) among 129 groups of individuals. RESULTS: Isocaloric replacement of saturated fats by complex carbohydrates for 10% of dietary calories resulted in blood total cholesterol falling by 0.52 (SE 0.03) mmol/l and low density lipoprotein cholesterol falling by 0.36 (0.05) mmol/l. Isocaloric replacement of complex carbohydrates by polyunsaturated fats for 5% of dietary calories resulted in total cholesterol falling by a further 0.13 (0.02) mmol/l and low density lipoprotein cholesterol falling by 0.11 (0.02) mmol/l. Similar replacement of carbohydrates by monounsaturated fats produced no significant effect on total or low density lipoprotein cholesterol. Avoiding 200 mg/day dietary cholesterol further decreased blood total cholesterol by 0.13 (0.02) mmol/l and low density lipoprotein cholesterol by 0.10 (0.02) mmol/l. CONCLUSIONS: In typical British diets replacing 60% of saturated fats by other fats and avoiding 60% of dietary cholesterol would reduce blood total cholesterol by about 0.8 mmol/l (that is, by 10-15%), with four fifths of this reduction being in low density lipoprotein cholesterol. PMID:9006469

  20. Quantitative ARG microimaging studies of two muscarinic antagonist isomers: Blocking and the effects of cocaine

    SciTech Connect

    Som, P.; Wang, G.J.; Oster, Z.H.

    1994-05-01

    The distribution of the racemic mixture of IQNP(1-Azabicyclo [2-2-2] oct-3-yl alpha-hydroxy-alpha-(1-iodo-propen-3-yl)-alpha-phenylacetate), a muscarinic antagonist was described earlier. Recently, the radioiodinated Z and E-(R,R) IQNP isomers have been prepared. Quantitative ARG studies using the Z and E isomers were performed in control rats and after pretreatment with ({plus_minus}) QNB or cocaine. High uptake of (Z)-IQNP was seen in the heart and brain with GI and urinary excretion. Lung uptake was lower than with the racemic IQNP. (Z)-IQNP uptake was maximal at 15 min p.i. with homogeneous distribution in the heart. In the brain, highest uptake was in the caudate, cortex, hippocampus, pons and thalamus. (Z)-IQNP showed higher cerebellar uptake and lower cortical uptake compared to (E)-IQNP. Clearance from brain was slower than bean. Heart and brain uptake of (E)-IQNP were markedly lower than the Z isomer. After QNB pretreatment, almost complete blocking of (Z)-IQNP uptake in heart and brain occurred. Cocaine did not significantly affect the distribution of IQNP. These data indicate that (Z)-IQNP has high affinity for the M2 muscarinic receptor with potential for brain and heart imaging. Cocaine appears to have little effect on the muscarinic-cholinergic receptors in the brain and heart.

  1. Extension trial of qigong for fibromyalgia: a quantitative and qualitative study.

    PubMed

    Sawynok, Jana; Lynch, Mary; Marcon, Dana

    2013-01-01

    This extension trial is an open-label observational trial of 20 subjects with fibromyalgia who undertook level 2 Chaoyi Fanhuan Qigong (CFQ) training following an earlier controlled trial of level 1 CFQ. Subjects practiced 60 min/day for 8 weeks and continued some daily practice for 6 months. Quantitative measures, assessed at baseline, 8 weeks, 4 and 6 months, were of pain, impact, sleep, physical and mental functions, and practice time. Qualitative comments also were recorded. Compared to baselines, CFQ practice led to significant improvements in pain, impact, sleep, and physical function in the 13 subjects (65%) who completed the trial; changes were present at 8 weeks and were maintained for the 6-month trial duration. A highly motivated subgroup of N = 5, who practiced the most, had the best outcomes in terms of end symptomology, and qualitative comments indicated health benefits in other domains as well. Qualitative comments by the remaining N = 8 trial completers and N = 7 withdrawals indicate different experiences with the practice. This extension trial indicates that diligent CFQ practice over time produces significant health gains in fibromyalgia in a subset of individuals. Future studies will need to address factors that might predispose to favourable outcomes. PMID:24069054

  2. Enhancing local action planning through quantitative flood risk analysis: a case study in Spain

    NASA Astrophysics Data System (ADS)

    Castillo-Rodríguez, Jesica Tamara; Escuder-Bueno, Ignacio; Perales-Momparler, Sara; Ramón Porta-Sancho, Juan

    2016-07-01

    This article presents a method to incorporate and promote quantitative risk analysis to support local action planning against flooding. The proposed approach aims to provide a framework for local flood risk analysis, combining hazard mapping with vulnerability data to quantify risk in terms of expected annual affected population, potential injuries, number of fatalities, and economic damages. Flood risk is estimated combining GIS data of loads, system response, and consequences and using event tree modelling for risk calculation. The study area is the city of Oliva, located on the eastern coast of Spain. Results from risk modelling have been used to inform local action planning and to assess the benefits of structural and non-structural risk reduction measures. Results show the potential impact on risk reduction of flood defences and improved warning communication schemes through local action planning: societal flood risk (in terms of annual expected affected population) would be reduced up to 51 % by combining both structural and non-structural measures. In addition, the effect of seasonal population variability is analysed (annual expected affected population ranges from 82 to 107 %, compared with the current situation, depending on occupancy rates in hotels and campsites). Results highlight the need for robust and standardized methods for urban flood risk analysis replicability at regional and national scale.

  3. Quantitative energy-dispersive x-ray diffraction for identification of counterfeit medicines: a preliminary study

    NASA Astrophysics Data System (ADS)

    Crews, Chiaki C. E.; O'Flynn, Daniel; Sidebottom, Aiden; Speller, Robert D.

    2015-06-01

    The prevalence of counterfeit and substandard medicines has been growing rapidly over the past decade, and fast, nondestructive techniques for their detection are urgently needed to counter this trend. In this study, energy-dispersive X-ray diffraction (EDXRD) combined with chemometrics was assessed for its effectiveness in quantitative analysis of compressed powder mixtures. Although EDXRD produces lower-resolution diffraction patterns than angular-dispersive X-ray diffraction (ADXRD), it is of interest for this application as it carries the advantage of allowing the analysis of tablets within their packaging, due to the higher energy X-rays used. A series of caffeine, paracetamol and microcrystalline cellulose mixtures were prepared with compositions between 0 - 100 weight% in 20 weight% steps (22 samples in total, including a centroid mixture), and were pressed into tablets. EDXRD spectra were collected in triplicate, and a principal component analysis (PCA) separated these into their correct positions in the ternary mixture design. A partial least-squares (PLS) regression model calibrated using this training set was validated using both segmented cross-validation, and with a test set of six samples (mixtures in 8:1:1 and 5⅓:2⅓:2⅓ ratios) - the latter giving a root-mean square error of prediction (RMSEP) of 1.30, 2.25 and 2.03 weight% for caffeine, paracetamol and cellulose respectively. These initial results are promising, with RMSEP values on a par with those reported in the ADXRD literature.

  4. A quantitative study relating observed shear in photospheric magnetic fields to repeated flaring

    NASA Astrophysics Data System (ADS)

    Hagyard, M. J.; Teuber, D.; West, E. A.; Smith, J. B.

    1984-03-01

    In this paper a quantitative evaluation of the shear in the magnetic field along the neutral line in an active region during an epoch of flare activity is presented. Shear is defined as the angular difference in the photosphere between the potential magnetic field, which fits the boundary conditions imposed by the observed line-of-sight field, and the observed magnetic field. For the active region studied, this angular difference (shear) is non-uniform along the neutral line with maxima occurring at the locations of repeated flare onsets. It is suggested that continued magnetic evolution causes the field's maximum shear to exceed a critical value of shear, resulting in a flare around the site of maximum shear. Evidently, the field at the site of the flare must relax to a state of shear somewhat below the critical value (but still far from potential), with subsequent evolution returning the field to the critical threshold. This inference is drawn because several flares occured at sites of maximum photospheric shear which were persistent in location.

  5. A quantitative study relating observed shear in photospheric magnetic fields to repeated flaring

    NASA Technical Reports Server (NTRS)

    Hagyard, M. J.; Teuber, D.; West, E. A.; Smith, J. B.

    1984-01-01

    In this paper a quantitative evaluation of the shear in the magnetic field along the neutral line in an active region during an epoch of flare activity is presented. Shear is defined as the angular difference in the photosphere between the potential magnetic field, which fits the boundary conditions imposed by the observed line-of-sight field, and the observed magnetic field. For the active region studied, this angular difference (shear) is non-uniform along the neutral line with maxima occurring at the locations of repeated flare onsets. It is suggested that continued magnetic evolution causes the field's maximum shear to exceed a critical value of shear, resulting in a flare around the site of maximum shear. Evidently, the field at the site of the flare must relax to a state of shear somewhat below the critical value (but still far from potential), with subsequent evolution returning the field to the critical threshold. This inference is drawn because several flares occured at sites of maximum photospheric shear which were persistent in location.

  6. Quantitative Proteomics Study of Larval Settlement in the Barnacle Balanus amphitrite

    PubMed Central

    Wang, Hao; Matsumura, Kiyotaka; Wong, Yue Him; Ravasi, Timothy; Qian, Pei-Yuan

    2014-01-01

    Barnacles are major sessile components of the intertidal areas worldwide, and also one of the most dominant fouling organisms in fouling communities. Larval settlement has a crucial ecological effect not only on the distribution of the barnacle population but also intertidal community structures. However, the molecular mechanisms involved in the transition process from the larval to the juvenile stage remain largely unclear. In this study, we carried out comparative proteomic profiles of stage II nauplii, stage VI nauplii, cyprids, and juveniles of the barnacle Balanus amphitrite using label-free quantitative proteomics, followed by the measurement of the gene expression levels of candidate proteins. More than 700 proteins were identified at each stage; 80 were significantly up-regulated in cyprids and 95 in juveniles vs other stages. Specifically, proteins involved in energy and metabolism, the nervous system and signal transduction were significantly up-regulated in cyprids, whereas proteins involved in cytoskeletal remodeling, transcription and translation, cell proliferation and differentiation, and biomineralization were up-regulated in juveniles, consistent with changes associated with larval metamorphosis and tissue remodeling in juveniles. These findings provided molecular evidence for the morphological, physiological and biological changes that occur during the transition process from the larval to the juvenile stages in B. amphitrite. PMID:24551147

  7. Prospective image registration for automated scan prescription of follow-up knee images in quantitative studies.

    PubMed

    Goldenstein, Janet; Schooler, Joseph; Crane, Jason C; Ozhinsky, Eugene; Pialat, Jean-Baptiste; Carballido-Gamio, Julio; Majumdar, Sharmila

    2011-06-01

    Consistent scan prescription for MRI of the knee is very important for accurate comparison of images in a longitudinal study. However, consistent scan region selection is difficult due to the complexity of the knee joint. We propose a novel method for registering knee images using a mutual information registration algorithm to align images in a baseline and follow-up exam. The output of the registration algorithm, three translations and three Euler angles, is then used to redefine the region to be imaged and acquire an identical oblique imaging volume in the follow-up exam as in the baseline. This algorithm is robust to articulation of the knee and anatomical abnormalities due to disease (e.g., osteophytes). The registration method is performed only on the distal femur and is not affected by the proximal tibia or soft tissues. We have incorporated this approach in a clinical MR system and have demonstrated its utility in automatically obtaining consistent scan regions between baseline and follow-up examinations, thus improving the precision of quantitative evaluation of cartilage. Results show an improvement with prospective registration in the coefficient of variation for cartilage thickness, cartilage volume and T2 relaxation measurements. PMID:21546186

  8. Quantitative study of ruthenium cross-over in direct methanol fuel cells during early operation hours

    NASA Astrophysics Data System (ADS)

    Schoekel, A.; Melke, J.; Bruns, M.; Wippermann, K.; Kuppler, F.; Roth, C.

    2016-01-01

    In direct methanol fuel cells (DMFC), ruthenium cross-over is an important degradation phenomenon. The loss of ruthenium from the anode, its transport through the membrane and its deposition onto the cathode are detrimental to the fuel cell performance and limit the fuel cell's lifetime. Here we present a quantitative study on the fraction of ruthenium being transferred from the anode to the cathode during early operation hours (0-100 h) of a DMFC. Already during fabrication of the MEA ruthenium is transferred to the cathode. In our pristine MEAs about 0.024 wt% Ru could be found in the cathode catalyst. The cell potential during operation seems to have only a minor influence on the dissolution process. In contrast, the operation time appears to be much more important. Our data hint at two dissolution processes: a fast process dominating the first hours of operation and a slower process, which is responsible for the ongoing ruthenium transfer during the fuel cell lifetime. After 2 h held at open circuit conditions the Ru content of the cathode side was 10 times higher than in the pristine MEA. In contrast, the slower process increased that amount only by a factor of two over the course of another 100 h.

  9. Functional Connectivity and Quantitative EEG in Women with Alcohol Use Disorders: A Resting-State Study.

    PubMed

    Herrera-Díaz, Adianes; Mendoza-Quiñones, Raúl; Melie-Garcia, Lester; Martínez-Montes, Eduardo; Sanabria-Diaz, Gretel; Romero-Quintana, Yuniel; Salazar-Guerra, Iraklys; Carballoso-Acosta, Mario; Caballero-Moreno, Antonio

    2016-05-01

    This study was aimed at exploring the electroencephalographic features associated with alcohol use disorders (AUD) during a resting-state condition, by using quantitative EEG and Functional Connectivity analyses. In addition, we explored whether EEG functional connectivity is associated with trait impulsivity. Absolute and relative powers and Synchronization Likelihood (SL) as a measure of functional connectivity were analyzed in 15 AUD women and fifteen controls matched in age, gender and education. Correlation analysis between self-report impulsivity as measured by the Barratt impulsiveness Scale (BIS-11) and SL values of AUD patients were performed. Our results showed increased absolute and relative beta power in AUD patients compared to matched controls, and reduced functional connectivity in AUD patients predominantly in the beta and alpha bands. Impaired connectivity was distributed at fronto-central and occipito-parietal regions in the alpha band, and over the entire scalp in the beta band. We also found that impaired functional connectivity particularly in alpha band at fronto-central areas was negative correlated with non-planning dimension of impulsivity. These findings suggest that functional brain abnormalities are present in AUD patients and a disruption of resting-state EEG functional connectivity is associated with psychopathological traits of addictive behavior. PMID:26660886

  10. A genome-wide linkage scan for iron phenotype quantitative trait loci: the HEIRS Family Study.

    PubMed

    Acton, R T; Snively, B M; Barton, J C; McLaren, C E; Adams, P C; Rich, S S; Eckfeldt, J H; Press, R D; Sholinsky, P; Leiendecker-Foster, C; McLaren, G D; Speechley, M R; Harris, E L; Dawkins, F W; Gordeuk, V R

    2007-06-01

    Iron overload phenotypes in persons with and without hemochromatosis are variable. To investigate this further, probands with hemochromatosis or evidence of elevated iron stores and their family members were recruited for a genome-wide linkage scan to identify potential quantitative trait loci (QTL) that contribute to variation in transferrin saturation (TS), unsaturated iron-binding capacity (UIBC), and serum ferritin (SF). Genotyping utilized 402 microsatellite markers with average spacing of 9 cM. A total of 943 individuals, 64% Caucasian, were evaluated from 174 families. After adjusting for age, gender, and race/ethnicity, there was evidence for linkage of UIBC to chromosome 4q logarithm of the odds (LOD) = 2.08, p = 0.001) and of UIBC (LOD = 9.52), TS (LOD = 4.78), and SF (LOD = 2.75) to the chromosome 6p region containing HFE (each p < 0.0001). After adjustments for HFE genotype and other covariates, there was evidence of linkage of SF to chromosome 16p (LOD = 2.63, p = 0.0007) and of UIBC to chromosome 5q (LOD = 2.12, p = 0.002) and to chromosome 17q (LOD = 2.19, p = 0.002). We conclude that these regions should be considered for fine mapping studies to identify QTL that contribute to variation in SF and UIBC. PMID:17539901

  11. A quantitative study on accumulation of age mass around stagnation points in nested flow systems

    NASA Astrophysics Data System (ADS)

    Jiang, Xiao-Wei; Wan, Li; Ge, Shemin; Cao, Guo-Liang; Hou, Guang-Cai; Hu, Fu-Sheng; Wang, Xu-Sheng; Li, Hailong; Liang, Si-Hai

    2012-12-01

    The stagnant zones in nested flow systems have been assumed to be critical to accumulation of transported matter, such as metallic ions and hydrocarbons in drainage basins. However, little quantitative research has been devoted to prove this assumption. In this paper, the transport of age mass is used as an example to demonstrate that transported matter could accumulate around stagnation points. The spatial distribution of model age is analyzed in a series of drainage basins of different depths. We found that groundwater age has a local or regional maximum value around each stagnation point, which proves the accumulation of age mass. In basins where local, intermediate and regional flow systems are all well developed, the regional maximum groundwater age occurs at the regional stagnation point below the basin valley. This can be attributed to the long travel distances of regional flow systems as well as stagnancy of the water. However, when local flow systems dominate, the maximum groundwater age in the basin can be located around the local stagnation points due to stagnancy, which are far away from the basin valley. A case study is presented to illustrate groundwater flow and age in the Ordos Plateau, northwestern China. The accumulation of age mass around stagnation points is confirmed by tracer age determined by 14C dating in two boreholes and simulated age near local stagnation points under different dispersivities. The results will help shed light on the relationship between groundwater flow and distributions of groundwater age, hydrochemistry, mineral resources, and hydrocarbons in drainage basins.

  12. Multiplexed and quantitative study of biomarker expression in tumor specimens using quantum dots

    NASA Astrophysics Data System (ADS)

    Wu, Aileen; True, Lawrence; Gao, Xiaohu

    2006-02-01

    When conjugated with targeting molecules, quantum dots (QD) can be used as powerful cancer diagnostic tools providing the molecular profiles of cancer cases based on common clinical biopsies. Such personalized analyses will enable doctors to treat and manage the patients' diseases more effectively. The unique optical properties (e.g., size-tunable emission, simultaneous excitation, high brightness and photostability) of these nanoparticles make them superior to conventionally popular organic fluorophores 1-2. Polymer-encapsulated, antibody-tagged QDs were prepared and used to successfully stain both fixed and live cells as well as clinical formalin-fixed paraffin-embedded (FFPE) tissue sections. In the tissue staining study, QD bioconjugates targeting mutated p53 and early growth response protein (egr-1) were used to examine prostate cancer tissues. The tissue slides were then analyzed with a wavelength-resolved spectrometer to accurately quantify the protein expression levels. In comparison to traditional qualitatively based diagnostic procedures, quantum dot nanotechnology allows for a more quantitative, rigorous and objective analysis of tissue specimens in question. In addition, new developments in imaging instrumentation could automate spectroscopy measurements and data analysis.

  13. Ictal and interictal phonophobia in migraine—a quantitative controlled study

    PubMed Central

    Ashkenazi, A.; Mushtaq, A.; Yang, I.; Oshinsky, ML.

    2016-01-01

    The aim of the study was to evaluate quantitatively ictal and interictal phonophobia in episodic migraine (EM). We included subjects with EM and age- and gender-matched controls. Sound stimuli were pure tones at frequencies of 1000, 4000 and 8000 Hz. Sound aversion thresholds (SATs) were determined as the minimal sound intensity perceived as unpleasant or painful. Migraineurs were examined both between and during attacks. We compared interictal SATs in migraineurs with those in controls. We also compared ictal and interictal SATs in migraineurs. Sixty migraineurs and 52 controls were included. Interictal mean SAT of migraineurs, averaged for the three frequencies, was significantly lower than that of controls [90.4 (0.8) dB vs. 105.9 (1.1) dB, respectively, P < 0.0001]. In migraineurs, mean ictal SAT, averaged for the three frequencies, was significantly lower than interictal SAT [76.0 (0.9) dB vs. 91.0 (0.8) dB, respectively, P < 0.0001]. Patients with EM exhibit increased sound aversion between attacks that is further augmented during an acute attack. PMID:19735532

  14. Quantitative study on dispersion relations of TIDs observed by an HF Doppler array

    NASA Technical Reports Server (NTRS)

    Tsutsui, M.; Ogawa, T.

    1985-01-01

    A quantitative study on the dispersion relation of traveling ionospheric disturbances (TIDs) was performed by using data obtained by an HF Doppler array. Observed data at three stations are digitized continuously with a sampling period of 10 sec. A schematic illustration of a running analysis method is given. Fourier components omega's and their wave vectors k's of the TIDs are calculated from these subset data from three stations by means of the cross-spectrum analysis. Diagrams of horizontal trace velocity V sub ph versus wave period T were also obtained. From these diagrams one can see clear cutoff periods of the internal mode of the atmospheric gravity waves. A morphological classification of the mode of the omega - k and V sub ph - T obtained through one year was performed. The estimation of the horizontal velocity vectors of the thermospheric wind form their dispersion relations was performed also. A key point of the method of obtaining the vectors is to estimate the tilt, in azimuthally different omega - k diagrams, of a resonant branch ascribed to the Brunt oscillations.

  15. Recommended Methods for Brain Processing and Quantitative Analysis in Rodent Developmental Neurotoxicity Studies.

    PubMed

    Garman, Robert H; Li, Abby A; Kaufmann, Wolfgang; Auer, Roland N; Bolon, Brad

    2016-01-01

    Neuropathology methods in rodent developmental neurotoxicity (DNT) studies have evolved with experience and changing regulatory guidance. This article emphasizes principles and methods to promote more standardized DNT neuropathology evaluation, particularly procurement of highly homologous brain sections and collection of the most reproducible morphometric measurements. To minimize bias, brains from all animals at all dose levels should be processed from brain weighing through paraffin embedding at one time using a counterbalanced design. Morphometric measurements should be anchored by distinct neuroanatomic landmarks that can be identified reliably on the faced block or in unstained sections and which address the region-specific circuitry of the measured area. Common test article-related qualitative changes in the developing brain include abnormal cell numbers (yielding altered regional size), displaced cells (ectopia and heterotopia), and/or aberrant differentiation (indicated by defective myelination or synaptogenesis), but rarely glial or inflammatory reactions. Inclusion of digital images in the DNT pathology raw data provides confidence that the quantitative analysis was done on anatomically matched (i.e., highly homologous) sections. Interpreting DNT neuropathology data and their presumptive correlation with neurobehavioral data requires an integrative weight-of-evidence approach including consideration of maternal toxicity, body weight, brain weight, and the pattern of findings across brain regions, doses, sexes, and ages. PMID:26296631

  16. Linkage disequilibrium fine mapping of quantitative trait loci: A simulation study

    PubMed Central

    Abdallah, Jihad M; Goffinet, Bruno; Cierco-Ayrolles, Christine; Pérez-Enciso, Miguel

    2003-01-01

    Recently, the use of linkage disequilibrium (LD) to locate genes which affect quantitative traits (QTL) has received an increasing interest, but the plausibility of fine mapping using linkage disequilibrium techniques for QTL has not been well studied. The main objectives of this work were to (1) measure the extent and pattern of LD between a putative QTL and nearby markers in finite populations and (2) investigate the usefulness of LD in fine mapping QTL in simulated populations using a dense map of multiallelic or biallelic marker loci. The test of association between a marker and QTL and the power of the test were calculated based on single-marker regression analysis. The results show the presence of substantial linkage disequilibrium with closely linked marker loci after 100 to 200 generations of random mating. Although the power to test the association with a frequent QTL of large effect was satisfactory, the power was low for the QTL with a small effect and/or low frequency. More powerful, multi-locus methods may be required to map low frequent QTL with small genetic effects, as well as combining both linkage and linkage disequilibrium information. The results also showed that multiallelic markers are more useful than biallelic markers to detect linkage disequilibrium and association at an equal distance. PMID:12939203

  17. Extension Trial of Qigong for Fibromyalgia: A Quantitative and Qualitative Study

    PubMed Central

    Lynch, Mary; Marcon, Dana

    2013-01-01

    This extension trial is an open-label observational trial of 20 subjects with fibromyalgia who undertook level 2 Chaoyi Fanhuan Qigong (CFQ) training following an earlier controlled trial of level 1 CFQ. Subjects practiced 60 min/day for 8 weeks and continued some daily practice for 6 months. Quantitative measures, assessed at baseline, 8 weeks, 4 and 6 months, were of pain, impact, sleep, physical and mental functions, and practice time. Qualitative comments also were recorded. Compared to baselines, CFQ practice led to significant improvements in pain, impact, sleep, and physical function in the 13 subjects (65%) who completed the trial; changes were present at 8 weeks and were maintained for the 6-month trial duration. A highly motivated subgroup of N = 5, who practiced the most, had the best outcomes in terms of end symptomology, and qualitative comments indicated health benefits in other domains as well. Qualitative comments by the remaining N = 8 trial completers and N = 7 withdrawals indicate different experiences with the practice. This extension trial indicates that diligent CFQ practice over time produces significant health gains in fibromyalgia in a subset of individuals. Future studies will need to address factors that might predispose to favourable outcomes. PMID:24069054

  18. Wetlab-2 - Quantitative PCR Tools for Spaceflight Studies of Gene Expression Aboard the International Space Station

    NASA Technical Reports Server (NTRS)

    Schonfeld, Julie E.

    2015-01-01

    Wetlab-2 is a research platform for conducting real-time quantitative gene expression analysis aboard the International Space Station. The system enables spaceflight genomic studies involving a wide variety of biospecimen types in the unique microgravity environment of space. Currently, gene expression analyses of space flown biospecimens must be conducted post flight after living cultures or frozen or chemically fixed samples are returned to Earth from the space station. Post-flight analysis is limited for several reasons. First, changes in gene expression can be transient, changing over a timescale of minutes. The delay between sampling on Earth can range from days to months, and RNA may degrade during this period of time, even in fixed or frozen samples. Second, living organisms that return to Earth may quickly re-adapt to terrestrial conditions. Third, forces exerted on samples during reentry and return to Earth may affect results. Lastly, follow up experiments designed in response to post-flight results must wait for a new flight opportunity to be tested.

  19. Myelin and iron concentration in the human brain: a quantitative study of MRI contrast.

    PubMed

    Stüber, Carsten; Morawski, Markus; Schäfer, Andreas; Labadie, Christian; Wähnert, Miriam; Leuze, Christoph; Streicher, Markus; Barapatre, Nirav; Reimann, Katja; Geyer, Stefan; Spemann, Daniel; Turner, Robert

    2014-06-01

    During the last five years ultra-high-field magnetic resonance imaging (MRI) has enabled an unprecedented view of living human brain. Brain tissue contrast in most MRI sequences is known to reflect mainly the spatial distributions of myelin and iron. These distributions have been shown to overlap significantly in many brain regions, especially in the cortex. It is of increasing interest to distinguish and identify cortical areas by their appearance in MRI, which has been shown to be feasible in vivo. Parcellation can benefit greatly from quantification of the independent contributions of iron and myelin to MRI contrast. Recent studies using susceptibility mapping claim to allow such a separation of the effects of myelin and iron in MRI. We show, using post-mortem human brain tissue, that this goal can be achieved. After MRI scanning of the block with appropriate T1 mapping and T2* weighted sequences, we section the block and apply a novel technique, proton induced X-ray emission (PIXE), to spatially map iron, phosphorus and sulfur elemental concentrations, simultaneously with 1μm spatial resolution. Because most brain phosphorus is located in myelin phospholipids, a calibration step utilizing element maps of sulfur enables semi-quantitative ex vivo mapping of myelin concentration. Combining results for iron and myelin concentration in a linear model, we have accurately modeled MRI tissue contrasts. Conversely, iron and myelin concentrations can now be estimated from appropriate MRI measurements in post-mortem brain samples. PMID:24607447

  20. Chemometric study of Andalusian extra virgin olive oils Raman spectra: Qualitative and quantitative information.

    PubMed

    Sánchez-López, E; Sánchez-Rodríguez, M I; Marinas, A; Marinas, J M; Urbano, F J; Caridad, J M; Moalem, M

    2016-08-15

    Authentication of extra virgin olive oil (EVOO) is an important topic for olive oil industry. The fraudulent practices in this sector are a major problem affecting both producers and consumers. This study analyzes the capability of FT-Raman combined with chemometric treatments of prediction of the fatty acid contents (quantitative information), using gas chromatography as the reference technique, and classification of diverse EVOOs as a function of the harvest year, olive variety, geographical origin and Andalusian PDO (qualitative information). The optimal number of PLS components that summarizes the spectral information was introduced progressively. For the estimation of the fatty acid composition, the lowest error (both in fitting and prediction) corresponded to MUFA, followed by SAFA and PUFA though such errors were close to zero in all cases. As regards the qualitative variables, discriminant analysis allowed a correct classification of 94.3%, 84.0%, 89.0% and 86.6% of samples for harvest year, olive variety, geographical origin and PDO, respectively. PMID:27260451

  1. Accuracy in Rietveld quantitative phase analysis: a comparative study of strictly monochromatic Mo and Cu radiations

    PubMed Central

    León-Reina, L.; García-Maté, M.; Álvarez-Pinazo, G.; Santacruz, I.; Vallcorba, O.; De la Torre, A. G.; Aranda, M. A. G.

    2016-01-01

    This study reports 78 Rietveld quantitative phase analyses using Cu Kα1, Mo Kα1 and synchrotron radiations. Synchrotron powder diffraction has been used to validate the most challenging analyses. From the results for three series with increasing contents of an analyte (an inorganic crystalline phase, an organic crystalline phase and a glass), it is inferred that Rietveld analyses from high-energy Mo Kα1 radiation have slightly better accuracies than those obtained from Cu Kα1 radiation. This behaviour has been established from the results of the calibration graphics obtained through the spiking method and also from Kullback–Leibler distance statistic studies. This outcome is explained, in spite of the lower diffraction power for Mo radiation when compared to Cu radiation, as arising because of the larger volume tested with Mo and also because higher energy allows one to record patterns with fewer systematic errors. The limit of detection (LoD) and limit of quantification (LoQ) have also been established for the studied series. For similar recording times, the LoDs in Cu patterns, ∼0.2 wt%, are slightly lower than those derived from Mo patterns, ∼0.3 wt%. The LoQ for a well crystallized inorganic phase using laboratory powder diffraction was established to be close to 0.10 wt% in stable fits with good precision. However, the accuracy of these analyses was poor with relative errors near to 100%. Only contents higher than 1.0 wt% yielded analyses with relative errors lower than 20%. PMID:27275132

  2. Quantitative genetic studies relating to the domestication of meadowfoam (Limnanthes spp. ) as a new oil crop

    SciTech Connect

    Abuelgasim, E.H.

    1982-01-01

    Meadowfoam (Limnanthes spp.) has recently aroused interest as a promising new source of industrial oil that is a good substitute for sperm whale oil. Fourteen natural populations of Limnanthes, involving two species and five taxonomic varieties, were studied for 12 quantitative characters, during two seasons. The objectives were: to evaluate the potential use of the populations for domestication purposes, study the interrelationships among characters, and to obtain heritability estimates for some of the important characters. A great deal of variability among the populations was observed for all the characters studied. Although no single taxon or population had all the desired characters combined, nevertheless, three populations of L. douglasii var. nivea and one population of L. douglasii var. sulphurea, gave consistently higher values for seed yield, seed number, plant dry weight, harvest index and fertility index, than L. alba or L. douglasii var. douglasii populations. The nivea group was also the earliest to flower, however, this group together with var. sulphurea population, suffer from severe seed shattering at maturity. In both seasons, seed yield was positively and highly significantly correlated with all of the other characters with the exception of days to the first flower and days to flower, which showed a highly significant negative correlation with seed yield. Stepwise multiple regression and path-coefficient analyses showed that seed number was the most important character in contribution to variation in seed yield; it accounted for over 85% of the variation in seed yield. The four characters: seed number, 100-seed weight, plant dry weight and harvest index, in that order, were the most important characters to be included in a multiple regression equation for determination of seed yield.

  3. Perceived leader integrity and employee job satisfaction: A quantitative study of U.S. aerospace engineers

    NASA Astrophysics Data System (ADS)

    Harper, Kay E.

    The goal of this quantitative study was to determine if there is a significant relationship between perceived leader integrity and employee job satisfaction. The population selected to be analyzed was U.S. Aerospace engineers. Two existing valid and reliable survey instruments were used to collect data. One of the surveys was the Perceived Leader Integrity Scale developed by Craig and Gustafson. The second survey was the Minnesota Satisfaction Questionnaire created by Weiss, Dawis, England, and Lofquist. The public professional networking site LinkedIn was used to invite U.S. Aerospace engineers to participate. The survey results were monitored by Survey Monkey and the sample data was analyzed using SPSS software. 184 responses were collected and of those, 96 were incomplete. 91 usable survey responses were left to be analyzed. When the results were plotted on an x-y plot, the data line had a slight negative slope. The plotted data showed a very small negative relationship between perceived leader integrity and employee job satisfaction. This relationship could be interpreted to mean that as perceived leader integrity improved, employee job satisfaction decreased only slightly. One explanation for this result could be that employees focused on their negative feelings about their current job assignment when they did not have to be concerned about the level of integrity with which their leader acted. The findings of this study reinforce the importance of employee's perception of a critical leader quality - integrity. For future research, a longitudinal study utilizing another sampling method other than convenience sampling may better statistically capture the relationship between perceived leader integrity and employee job satisfaction for U.S. aerospace engineers.

  4. Community health orientation of Indian Journal of Endocrinology and Metabolism: A bibliometric analysis of Indian Journal of Endocrinology and Metabolism

    PubMed Central

    Kaushal, Kanica; Kalra, Sanjay

    2015-01-01

    Background: Endocrine and metabolic diseases especially diabetes have become focus areas for public health professionals. Indian Journal of Endocrinology and Metabolism (IJEM), a publication of Endocrine Society of India, is a peer-reviewed online journal, which covers technical and clinical studies related to health, ethical and social issues in field of diabetes, endocrinology and metabolism. This bibliometric analysis assesses the journal from a community health perspective. Materials and Methods: Every article published in IJEM over a period of 4 years (2011–2014) was accessed to review coverage of community health in the field of endocrinology. Results: Seven editorials, 30 review articles, 41 original articles, 12 brief communications, 20 letter to editors, 4 articles on guidelines and 2 in the section “endocrinology and gender” directly or indirectly dealt with community health aspects of endocrinology. Together these amounted to 17% of all articles published through these 4 years. There were 14 articles on general, 60 pertaining to pancreas and diabetes, 10 on thyroid, 7 on pituitary/adrenal/gonads, 21 on obesity and metabolism and 4 on parathyroid and bone; all community medicine related. Conclusion: Community health is an integral part of the modern endocrinology diabetology and metabolism practice and it received adequate journal space during the last 4 years. The coverage is broad based involving all the major endocrine disorders. PMID:25932398

  5. A quantitative study of exocytosis of titanium dioxide nanoparticles from neural stem cells

    NASA Astrophysics Data System (ADS)

    Wang, Yanli; Wu, Qiuxia; Sui, Keke; Chen, Xin-Xin; Fang, Jie; Hu, Xuefeng; Wu, Minghong; Liu, Yuanfang

    2013-05-01

    Nanoparticles (NPs) have been widely studied and applied in biomedicine and other fields. It is important to know the basic process of interaction between NPs and cells in terms of cellular endocytosis and exocytosis. However, little attention has been paid to the cellular exocytosis of NPs. Herein, using a multi-step cellular subculture method, we ascertain quantitatively the endocytosis and exocytosis of widely used TiO2 NPs using the neural stem cells (NSC) as a cellular model and ICP-AES as an analytic measure. Irrespective of the type and dose of TiO2 NPs, approximately 30% of the total TiO2 NPs entered NSCs after 48 h incubation. In the first 24 h after removing TiO2NPs, from the culture medium, about 35.0%, 34.6% and 41.7% of NP1 (50 nm), NP2 (30 nm) and NTs (nanotubes, 100 nm × 4-6 nm) were released (exocytosed) from cells, respectively. The release decreased over time, and became negligible at 72 h. Exocytosis did not happen during cell division. In addition, our results suggested that both endocytosis and exocytosis of TiO2NPs were energy-dependent processes, and NPs uptake by cells was influenced by serum proteins. Furthermore, we achieved primary dynamic confocal imaging of the exocytosis, allowing tracking of TiO2 NPs from NSCs. These findings may benefit studies on nanotoxicology and nanomedicine of TiO2 NPs.Nanoparticles (NPs) have been widely studied and applied in biomedicine and other fields. It is important to know the basic process of interaction between NPs and cells in terms of cellular endocytosis and exocytosis. However, little attention has been paid to the cellular exocytosis of NPs. Herein, using a multi-step cellular subculture method, we ascertain quantitatively the endocytosis and exocytosis of widely used TiO2 NPs using the neural stem cells (NSC) as a cellular model and ICP-AES as an analytic measure. Irrespective of the type and dose of TiO2 NPs, approximately 30% of the total TiO2 NPs entered NSCs after 48 h incubation. In the

  6. Quantitative study of fluctuation effects by fast lattice Monte Carlo simulations: Compression of grafted homopolymers

    SciTech Connect

    Zhang, Pengfei; Wang, Qiang

    2014-01-28

    Using fast lattice Monte Carlo (FLMC) simulations [Q. Wang, Soft Matter 5, 4564 (2009)] and the corresponding lattice self-consistent field (LSCF) calculations, we studied a model system of grafted homopolymers, in both the brush and mushroom regimes, in an explicit solvent compressed by an impenetrable surface. Direct comparisons between FLMC and LSCF results, both of which are based on the same Hamiltonian (thus without any parameter-fitting between them), unambiguously and quantitatively reveal the fluctuations/correlations neglected by the latter. We studied both the structure (including the canonical-ensemble averages of the height and the mean-square end-to-end distances of grafted polymers) and thermodynamics (including the ensemble-averaged reduced energy density and the related internal energy per chain, the differences in the Helmholtz free energy and entropy per chain from the uncompressed state, and the pressure due to compression) of the system. In particular, we generalized the method for calculating pressure in lattice Monte Carlo simulations proposed by Dickman [J. Chem. Phys. 87, 2246 (1987)], and combined it with the Wang-Landau–Optimized Ensemble sampling [S. Trebst, D. A. Huse, and M. Troyer, Phys. Rev. E 70, 046701 (2004)] to efficiently and accurately calculate the free energy difference and the pressure due to compression. While we mainly examined the effects of the degree of compression, the distance between the nearest-neighbor grafting points, the reduced number of chains grafted at each grafting point, and the system fluctuations/correlations in an athermal solvent, the θ-solvent is also considered in some cases.

  7. Assessment of Suitable Reference Genes for Quantitative Gene Expression Studies in Melon Fruits

    PubMed Central

    Kong, Qiusheng; Gao, Lingyun; Cao, Lei; Liu, Yue; Saba, Hameed; Huang, Yuan; Bie, Zhilong

    2016-01-01

    Melon (Cucumis melo L.) is an attractive model plant for investigating fruit development because of its morphological, physiological, and biochemical diversity. Quantification of gene expression by quantitative reverse transcription polymerase chain reaction (qRT-PCR) with stably expressed reference genes for normalization can effectively elucidate the biological functions of genes that regulate fruit development. However, the reference genes for data normalization in melon fruits have not yet been systematically validated. This study aims to assess the suitability of 20 genes for their potential use as reference genes in melon fruits. Expression variations of these genes were measured in 24 samples that represented different developmental stages of fertilized and parthenocarpic melon fruits by qRT-PCR analysis. GeNorm identified ribosomal protein L (CmRPL) and cytosolic ribosomal protein S15 (CmRPS15) as the best pair of reference genes, and as many as five genes including CmRPL, CmRPS15, TIP41-like family protein (CmTIP41), cyclophilin ROC7 (CmCYP7), and ADP ribosylation factor 1 (CmADP) were required for more reliable normalization. NormFinder ranked CmRPS15 as the best single reference gene, and RAN GTPase gene family (CmRAN) and TATA-box binding protein (CmTBP2) as the best combination of reference genes in melon fruits. Their effectiveness was further validated by parallel analyses on the activities of soluble acid invertase and sucrose phosphate synthase, and expression profiles of their respective encoding genes CmAIN2 and CmSPS1, as well as sucrose contents during melon fruit ripening. The validated reference genes will help to improve the accuracy of gene expression studies in melon fruits. PMID:27536316

  8. EX VIVO STUDY OF QUANTITATIVE ULTRASOUND PARAMETERS IN FATTY RABBIT LIVERS

    PubMed Central

    Ghoshal, Goutam; Lavarello, Roberto J.; Kemmerer, Jeremy P.; Miller, Rita J.; Oelze, Michael L.

    2012-01-01

    Nonalcoholic fatty liver disease (NAFLD) affects more than 30% of Americans, and with increasing problems of obesity in the United States, NAFLD is poised to become an even more serious medical concern. At present, accurate classification of steatosis (fatty liver) represents a significant challenge. In this study, the use of high-frequency (8 to 25 MHz) quantitative ultrasound (QUS) imaging to quantify fatty liver was explored. QUS is an imaging technique that can be used to quantify properties of tissue giving rise to scattered ultrasound. The changes in the ultrasound properties of livers in rabbits undergoing atherogenic diets of varying durations were investigated using QUS. Rabbits were placed on a special fatty diet for 0, 3, or 6 weeks. The fattiness of the livers was quantified by estimating the total lipid content of the livers. Ultrasonic properties, such as speed of sound, attenuation, and backscatter coefficients, were estimated in ex vivo rabbit liver samples from animals that had been on the diet for varying periods. Two QUS parameters were estimated based on the backscatter coefficient: effective scatterer diameter (ESD) and effective acoustic concentration (EAC), using a spherical Gaussian scattering model. Two parameters were estimated based on the backscattered envelope statistics (the k parameter and the μ parameter) according to the homodyned K distribution. The speed of sound decreased from 1574 to 1565 m/s and the attenuation coefficient increased from 0.71 to 1.27 dB/cm/MHz, respectively, with increasing fat content in the liver. The ESD decreased from 31 to 17 μm and the EAC increased from 38 to 63 dB/cm3 with increasing fat content in the liver. A significant increase in the μ parameter from 0.18 to 0.93 scatterers/mm3 was observed with increasing fat content in the liver samples. The results of this study indicate that QUS parameters are sensitive to fat content in the liver. PMID:23062376

  9. Quantitative Study of the Characteristics of Effective Internal Medicine Noon Conference Presentations.

    PubMed

    Fraser, Traci; Sargsyan, Zaven; Baggett, Travis P; Baggett, Meridale

    2016-05-01

    Background Increasing demands on residents' time have made it critically important to maximize the effectiveness of didactic activities and motivate independent study. Objective Our aim was to correlate characteristics of noon conferences with internal medicine (IM) residents' ratings of perceived effectiveness and intent to pursue independent reading. Methods We assessed characteristics of each noon conference by direct observation using predetermined metrics. We surveyed IM residents to assess their perception of the conference's effectiveness and their intention to pursue additional reading. A variety of modeling techniques were used to discern meaningful correlations of effectiveness and motivation. Results A total of 649 evaluations of 29 conferences were submitted by 153 of 185 (83%) residents in the program. Median effectiveness score was 6 (on a scale of 1 to 7). Clinicopathological conferences had 0.55-point higher effectiveness scores than traditional conferences (P = .011). In multivariable analyses focusing on traditional conferences, summary statement inclusion was significantly associated with 0.43-point higher effectiveness scores (P = .016), and having resident speakers was associated with 0.50-point higher effectiveness scores than unfamiliar faculty (P = .045). Conferences with higher effectiveness scores had significantly higher proportions of respondents indicating intention to read. Conclusions This is the first study to quantitatively assess correlations of high effectiveness ratings of noon conferences in a residency program. Intention to read improved with increasing effectiveness scores of conferences, suggesting residents are more inclined to pursue self-directed learning when topics are well presented. Considering these attributes in designs of didactic sessions may enhance their educational value. PMID:27168885

  10. Quantitative evaluation of approximal contacts in Class 2 composite resin restorations: a clinical study.

    PubMed

    Wang, J C; Charbeneau, G T; Gregory, W A; Dennison, J B

    1989-01-01

    The purpose of this study was to develop an accurate and reproducible intraoral method of measuring the distance between two teeth, and to conduct a clinical pilot study of the effect of placement of a class 2 posterior resin restoration upon this intertooth dimension. A Kaman Sciences KD-2611 noncontact displacement measuring system with a 1U unshielding sensor, based upon the variable resistance of eddy current, was used for the intraoral measurement. Seven patients requiring conservative interproximal restorations (initial placements or replacements) on the premolars were selected. Addition silicone impressions were taken of the posterior quadrants from which low-fusing metal (Cerrolow-136) casts were made. Composite resin copings constructed on modified rubber dam clamps were fabricated for the restoration and adjacent teeth upon these metal casts. Aluminum targets and Plexiglas holders for the sensor were attached to the bow of the rubber dam clamp with light-activated composite resin. Quantitative measurements of intertooth distance were made preoperatively, postoperatively, and at one-week and 4 1/2-month recalls after placement of class 2 composite resin restorations for 11 teeth. Four unrestored premolars served as a control. The data were tabulated and analyzed using one-way analysis of variance. The results indicated that the mean postoperative intercoping distance for restored teeth increased after a multiple wedging technique had been applied during restorative procedure. At the one-week recall, these distances had decreased. The 4 1/2-month measurements showed a further decrease with an average loss of 15 microns from the preoperative baseline. PMID:2639320

  11. Assessment of Suitable Reference Genes for Quantitative Gene Expression Studies in Melon Fruits.

    PubMed

    Kong, Qiusheng; Gao, Lingyun; Cao, Lei; Liu, Yue; Saba, Hameed; Huang, Yuan; Bie, Zhilong

    2016-01-01

    Melon (Cucumis melo L.) is an attractive model plant for investigating fruit development because of its morphological, physiological, and biochemical diversity. Quantification of gene expression by quantitative reverse transcription polymerase chain reaction (qRT-PCR) with stably expressed reference genes for normalization can effectively elucidate the biological functions of genes that regulate fruit development. However, the reference genes for data normalization in melon fruits have not yet been systematically validated. This study aims to assess the suitability of 20 genes for their potential use as reference genes in melon fruits. Expression variations of these genes were measured in 24 samples that represented different developmental stages of fertilized and parthenocarpic melon fruits by qRT-PCR analysis. GeNorm identified ribosomal protein L (CmRPL) and cytosolic ribosomal protein S15 (CmRPS15) as the best pair of reference genes, and as many as five genes including CmRPL, CmRPS15, TIP41-like family protein (CmTIP41), cyclophilin ROC7 (CmCYP7), and ADP ribosylation factor 1 (CmADP) were required for more reliable normalization. NormFinder ranked CmRPS15 as the best single reference gene, and RAN GTPase gene family (CmRAN) and TATA-box binding protein (CmTBP2) as the best combination of reference genes in melon fruits. Their effectiveness was further validated by parallel analyses on the activities of soluble acid invertase and sucrose phosphate synthase, and expression profiles of their respective encoding genes CmAIN2 and CmSPS1, as well as sucrose contents during melon fruit ripening. The validated reference genes will help to improve the accuracy of gene expression studies in melon fruits. PMID:27536316

  12. The effect of physical loading on calcaneus quantitative ultrasound measurement: a cross-section study

    PubMed Central

    2012-01-01

    Background Physical loading leads to a deformation of bone microstructure and may influence quantitative ultrasound (QUS) parameters. This study aims at evaluating the effect of physical loading on bone QUS measurement, and further, on the potential of diagnosing osteoporosis using QUS method under physical loading condition. Methods 16 healthy young females (control group) and 45 postmenopausal women (divided into 3 groups according to the years since menopause (YSM)) were studied. QUS parameters were measured at calcaneus under self-weight loading (standing) and no loading (sitting) conditions. Weight-normalized QUS parameter (QUS parameter measured under loading condition divided by the weight of the subject) was proposed to evaluate the influence of loading. T-test, One-Way analysis of variance (one way ANOVA) and receiver operating characteristic (ROC) analysis were applied for analysis. Results In QUS parameters, mainly normalized broadband ultrasound attenuation (nBUA), measured with loading significantly differed from those measured without loading (p < 0.05). The relative changes of weight-normalized QUS parameters on postmenopausal women with respect to premenopausal women under loading condition were larger than those on traditional QUS parameters measured without loading. In ROC analysis, weight-normalized QUS parameters showed their stronger discriminatory ability for menopause. Conclusions Physical loading substantially influenced bone QUS measurement (mainly nBUA). Weight-normalized QUS parameters can discriminate menopause more effectively. By considering the high relationship between menopause and osteoporosis, an inference was drawn that adding physical loading during measurement may be a probable way to improve the QUS based osteoporosis diagnosis. PMID:22584084

  13. Quantitative detection of caffeine in human skin by confocal Raman spectroscopy--A systematic in vitro validation study.

    PubMed

    Franzen, Lutz; Anderski, Juliane; Windbergs, Maike

    2015-09-01

    For rational development and evaluation of dermal drug delivery, the knowledge of rate and extent of substance penetration into the human skin is essential. However, current analytical procedures are destructive, labor intense and lack a defined spatial resolution. In this context, confocal Raman microscopy bares the potential to overcome current limitations in drug depth profiling. Confocal Raman microscopy already proved its suitability for the acquisition of qualitative penetration profiles, but a comprehensive investigation regarding its suitability for quantitative measurements inside the human skin is still missing. In this work, we present a systematic validation study to deploy confocal Raman microscopy for quantitative drug depth profiling in human skin. After we validated our Raman microscopic setup, we successfully established an experimental procedure that allows correlating the Raman signal of a model drug with its controlled concentration in human skin. To overcome current drawbacks in drug depth profiling, we evaluated different modes of peak correlation for quantitative Raman measurements and offer a suitable operating procedure for quantitative drug depth profiling in human skin. In conclusion, we successfully demonstrate the potential of confocal Raman microscopy for quantitative drug depth profiling in human skin as valuable alternative to destructive state-of-the-art techniques. PMID:25828208

  14. Research fronts analysis : A bibliometric to identify emerging fields of research

    NASA Astrophysics Data System (ADS)

    Miwa, Sayaka; Ando, Satoko

    Research fronts analysis identifies emerging areas of research through observing co-clustering in highly-cited papers. This article introduces the concept of research fronts analysis, explains its methodology and provides case examples. It also demonstrates developing research fronts in Japan by looking at the past winners of Thomson Reuters Research Fronts Awards. Research front analysis is currently being used by the Japanese government to determine new trends in science and technology. Information professionals can also utilize this bibliometric as a research evaluation tool.

  15. Examination of Information Technology (IT) Certification and the Human Resources (HR) Professional Perception of Job Performance: A Quantitative Study

    ERIC Educational Resources Information Center

    O'Horo, Neal O.

    2013-01-01

    The purpose of this quantitative survey study was to test the Leontief input/output theory relating the input of IT certification to the output of the English-speaking U.S. human resource professional perceived IT professional job performance. Participants (N = 104) rated their perceptions of IT certified vs. non-IT certified professionals' job…

  16. A Quantitative Study into the Information Technology Project Portfolio Practice: The Impact on Information Technology Project Deliverables

    ERIC Educational Resources Information Center

    Yu, Wei

    2013-01-01

    This dissertation applied the quantitative approach to the data gathered from online survey questionnaires regarding the three objects: Information Technology (IT) Portfolio Management, IT-Business Alignment, and IT Project Deliverables. By studying this data, this dissertation uncovered the underlying relationships that exist between the…

  17. MOLECULAR TOPOLOGY AND NARCOSIS - A QUANTITATIVE STRUCTURE-ACTIVITY RELATIONSHIP (QSAR) STUDY OF ALCOHOLS USING COMPLEMENTARY INFORMATION CONTENT (CIC)

    EPA Science Inventory

    A newly formulated information -theoretic topological index - complementary information content (CIC) - defined for the planar chemical graph of molecules is applied in the QSAR studies of congeneric series of alcohols. Results show that CIC can quantitatively predict the LC50 va...

  18. Quantitative study of non-covalent interactions at the electrode-electrolyte interface using cyanide-modified Pt(111) electrodes.

    SciTech Connect

    Escudero-Escribano, M.; Michoff, M. E. Z.; Leiva, E. P. M.; Markovic, N. M.; Gutierrez, C.; Cuesta, A.

    2011-08-22

    Cations at the outer Helmholtz plane (OHP) can interact through non-covalent interactions with species at the inner Helmholtz plane (IHP), which are covalently bonded to the electrode surface, thereby affecting the structure and the properties of the electrochemical double layer. These non-covalent interactions can be studied quantitatively using cyanide-modified Pt(111) electrodes.

  19. A Quantitative Study of a Software Tool that Supports a Part-Complete Solution Method on Learning Outcomes

    ERIC Educational Resources Information Center

    Garner, Stuart

    2009-01-01

    This paper reports on the findings from a quantitative research study into the use of a software tool that was built to support a part-complete solution method (PCSM) for the learning of computer programming. The use of part-complete solutions to programming problems is one of the methods that can be used to reduce the cognitive load that students…

  20. Dietary nitrate reduces skeletal muscle oxygenation response to physical exercise: a quantitative muscle functional MRI study.

    PubMed

    Bentley, Rachel; Gray, Stuart R; Schwarzbauer, Christian; Dawson, Dana; Frenneaux, Michael; He, Jiabao

    2014-07-01

    Dietary inorganic nitrate supplementation (probably via conversion to nitrite) increases skeletal muscle metabolic efficiency. In addition, it may also cause hypoxia-dependent vasodilation and this has the potential to augment oxygen delivery to exercising skeletal muscle. However, direct evidence for the latter with spatial localization to exercising muscle groups does not exist. We employed quantitative functional MRI (fMRI) to characterize skeletal muscle oxygen utilization and replenishment by assessment of tissue oxygenation maximal change and recovery change, respectively. Eleven healthy subjects were enrolled, of whom 9 (age 33.3 ± 4.4 years, five males) completed the study. Each subject took part in three MRI visits, with dietary nitrate (7cl concentrated beetroot juice) consumed before the third visit. During each visit fMRIs were conducted concurrently with plantar flexion exercise at workloads of 15% and 25% maximum voluntary contraction (MVC). No significant changes were found between visits 1 and 2 in the fMRI measures. A decrease in maximal change was found at 15% MVC in soleus between visits 2 and 3 (5.12 ± 2.36 to 2.55 ± 1.42, P = 0.004) and between visits 1 and 3 (4.43 ± 2.12 to 2.55 ± 1.42, P = 0.043), but not at 25% MVC or within gastrocnemius. There was no difference in recovery change between visits. We found that dietary nitrate supplementation reduces tissue oxygenation alterations during physical exercise in skeletal muscle. This effect is more prominent in muscles with predominantly type 1 fibers and at lower workloads. This indicates that in healthy subjects dietary nitrate predominantly affects skeletal muscle energy efficiency with no change in oxygen delivery. PMID:25052493

  1. A quantitative acoustic emission study on fracture processes in ceramics based on wavelet packet decomposition

    SciTech Connect

    Ning, J. G.; Chu, L.; Ren, H. L.

    2014-08-28

    We base a quantitative acoustic emission (AE) study on fracture processes in alumina ceramics on wavelet packet decomposition and AE source location. According to the frequency characteristics, as well as energy and ringdown counts of AE, the fracture process is divided into four stages: crack closure, nucleation, development, and critical failure. Each of the AE signals is decomposed by a 2-level wavelet package decomposition into four different (from-low-to-high) frequency bands (AA{sub 2}, AD{sub 2}, DA{sub 2}, and DD{sub 2}). The energy eigenvalues P{sub 0}, P{sub 1}, P{sub 2}, and P{sub 3} corresponding to these four frequency bands are calculated. By analyzing changes in P{sub 0} and P{sub 3} in the four stages, we determine the inverse relationship between AE frequency and the crack source size during ceramic fracture. AE signals with regard to crack nucleation can be expressed when P{sub 0} is less than 5 and P{sub 3} more than 60; whereas AE signals with regard to dangerous crack propagation can be expressed when more than 92% of P{sub 0} is greater than 4, and more than 95% of P{sub 3} is less than 45. Geiger location algorithm is used to locate AE sources and cracks in the sample. The results of this location algorithm are consistent with the positions of fractures in the sample when observed under a scanning electronic microscope; thus the locations of fractures located with Geiger's method can reflect the fracture process. The stage division by location results is in a good agreement with the division based on AE frequency characteristics. We find that both wavelet package decomposition and Geiger's AE source locations are suitable for the identification of the evolutionary process of cracks in alumina ceramics.

  2. Quantitative study of tectonic geomorphology along Haiyuan fault based on airborne LiDAR

    USGS Publications Warehouse

    Chen, Tao; Zhang, Pei Zhen; Liu, Jing; Li, Chuan You; Ren, Zhi Kun; Hudnut, Kenneth W.

    2014-01-01

    High-precision and high-resolution topography are the fundamental data for active fault research. Light detection and ranging (LiDAR) presents a new approach to build detailed digital elevation models effectively. We take the Haiyuan fault in Gansu Province as an example of how LiDAR data may be used to improve the study of active faults and the risk assessment of related hazards. In the eastern segment of the Haiyuan fault, the Shaomayin site has been comprehensively investigated in previous research because of its exemplary tectonic topographic features. Based on unprecedented LiDAR data, the horizontal and vertical coseismic offsets at the Shaomayin site are described. The measured horizontal value is about 8.6 m, and the vertical value is about 0.8 m. Using prior dating ages sampled from the same location, we estimate the horizontal slip rate as 4.0 ± 1.0 mm/a with high confidence and define that the lower bound of the vertical slip rate is 0.4 ± 0.1 mm/a since the Holocene. LiDAR data can repeat the measurements of field work on quantifying offsets of tectonic landform features quite well. The offset landforms are visualized on an office computer workstation easily, and specialized software may be used to obtain displacement quantitatively. By combining precious chronological results, the fundamental link between fault activity and large earthquakes is better recognized, as well as the potential risk for future earthquake hazards.

  3. Changes in lung morphology and cell number in radiation pneumonitis and fibrosis: a quantitative ultrastructural study

    SciTech Connect

    Vergara, J.A.; Raymond, U.; Thet, L.A.

    1987-05-01

    We used stereologic-morphometric techniques to obtain a detailed quantitative picture of the changes in lung ultrastructure of rats at 12 and 26 weeks after unilateral thoracic irradiation with 3000 cGy. At 12 weeks post-radiation, the total number type 1 epithelial cells, type 2 epithelial cells and capillary endothelial cells were decreased 50-70%, total type 1 epithelial and capillary surface areas were decreased 55-60%, and the total volume of intracapillary blood was decreased 75%. The interstitial cells and matrix together accounted for more than 9% of the peripheral lung tissue volume including air, compared to 3% in controls. The numerical density of interstitial cells was increased to 3-fold the control value. The numerical density of interstitial cells was increased to 3-fold the control value. Although fibroblasts still comprised the largest interstitial cell subgroup, the numerical density of mast cells was increased over 150-fold and other inflammatory and immune cells were increased to a lesser extent. At 26 weeks post-radiation, the number, volume, and surface area of the type 1 epithelium and capillary endothelium had further decreased to only 5-10% of control values. The total number of type 2 epithelial cells was reduced by 75% but the volume density was actually increased because of a 4-fold increase in the mean cell volume. The interstitial cells and matrix now comprised over 77% of total peripheral lung tissue volume including air as compared to 6% in controls. Mast cells and plasma cells comprised 11% and 19% of all interstitial cells respectively and the densities of these cells were 540 and 180-fold the control value respectively. The relation of these morphometric findings to the results of previous morphologic studies is discussed.

  4. Effect of random coincidences for quantitative cardiac PET studies using 3D oxygen-15 water scans

    NASA Astrophysics Data System (ADS)

    Bouchareb, Y.; Thielemans, K.; Spinks, T.; Rimoldi, O.; Camici, P. G.

    2006-03-01

    The effect of random coincidences estimation methods on the quantitative accuracy of iterative and analytic reconstruction methods to determine myocardial blood flow (MBF) in PET studies using H II 15O has been investigated. Dynamic scans were acquired on the EXACT3D PET scanner on pigs after H II 15O injection (resting and dipyridamoleinduced stress). Radioactive microspheres (MS) were used to provide a "gold standard" of MBF values. The online subtraction (OS) and maximum likelihood (ML) methods for estimating randoms were combined with (i) 3D-RP, (ii) FORE + attenuation-weighted OSEM, (iii) FORE-FBP and (iv) 3D-OSEM. Factor images were generated and resliced to short axis images; 16 ROIs were defined in the left myocardium and 2 ROIs in the left and right cavities. ROIs were projected onto the dynamic images to extract time-activity-curves, which were then fitted to a single compartment model to estimate absolute MBF. Microsphere measurements were obtained in a similar way and 64 pairs of measurements were made. The ML method improved the SNR of 3D-RP, FORE-FBP, FORE-OSEM, and 3D-OSEM by 8%, 8%, 7% and 3% respectively. Compared to the OS method, the ML method improved the accuracy of coronary flow reserve values of 3DOSEM, 3D-RP, FORE-OSEM and FORE-FBP by 9%, 7%, 1% and 3% respectively. Regression analysis provided better correlation with 3D-OSEM and FORE-OSEM when combined with the ML method. We conclude that the ML method for estimating randoms combined with 3D-OSEM and FORE-OSEM delivers the best performance for absolute quantification of MBF using H II 15O when compared with microsphere measurements.

  5. A Quantitative Study of Tethered Chains in Various Solution Conditions Using Langmuir Diblock Copolymer Monolayers

    SciTech Connect

    Kent, Michael S.

    1999-08-13

    This article summarizes our investigations of tethered chain systems using Langmuir monolayer of polydimethysiloxane-poly styrene (PDMS-PS) diblock copolymers on organic liquids. In this system, the PDMS block adsorbs to the air surface while the PS block dangles into the subphase liquid. The air surface can be made either repulsive or attractive for the tethered PS chain segments by choosing a subphase liquid which has a surface tension lower or greater than that of PS, respectively. The segment profile of the PS block is determined by neutron reflection as a function of the surface density, the molecular weights of the PS and PDMS blocks, and the solution conditions. We cover the range of reduced surface density (SIGMA) characteristic of the large body of data in the literature for systems of chains tethered onto solid surfaces from dilute solution in good or theta solvent conditions (SIGMA < 12). We emphasize quantitative comparisons with analytical profile forms and scaling predictions. We find that the strong-stretching limit invoked in analytical SCF and scaling theories is not valid over this Z range. On the other hand, over a large portion of this range (SIGMA < 5) tethered layers are well described by a renormalization group theory addressing weakly interacting or noninteracting chains. Simultaneous with the study of the profile form, the free energy of the chains is examined through the surface tension. A strong increase in the surface pressure is observed with increasing surface density which determines the maximum surface density which can be achieved. This apparently nonequilibrium effect is attributed to steric interactions and limited lateral interpenetration. This effect may explain several outstanding discrepancies regarding the adsorption of end-functionalized chains and diblock copolymers onto solid surfaces.

  6. Detecting Gene-Environment Interactions for a Quantitative Trait in a Genome-Wide Association Study.

    PubMed

    Zhang, Pingye; Lewinger, Juan Pablo; Conti, David; Morrison, John L; Gauderman, W James

    2016-07-01

    A genome-wide association study (GWAS) typically is focused on detecting marginal genetic effects. However, many complex traits are likely to be the result of the interplay of genes and environmental factors. These SNPs may have a weak marginal effect and thus unlikely to be detected from a scan of marginal effects, but may be detectable in a gene-environment (G × E) interaction analysis. However, a genome-wide interaction scan (GWIS) using a standard test of G × E interaction is known to have low power, particularly when one corrects for testing multiple SNPs. Two 2-step methods for GWIS have been previously proposed, aimed at improving efficiency by prioritizing SNPs most likely to be involved in a G × E interaction using a screening step. For a quantitative trait, these include a method that screens on marginal effects [Kooperberg and Leblanc, 2008] and a method that screens on variance heterogeneity by genotype [Paré et al., 2010] In this paper, we show that the Paré et al. approach has an inflated false-positive rate in the presence of an environmental marginal effect, and we propose an alternative that remains valid. We also propose a novel 2-step approach that combines the two screening approaches, and provide simulations demonstrating that the new method can outperform other GWIS approaches. Application of this method to a G × Hispanic-ethnicity scan for childhood lung function reveals a SNP near the MARCO locus that was not identified by previous marginal-effect scans. PMID:27230133

  7. Benefits of an Advanced Quantitative Precipitation Information System - San Francisco Bay Area Case Study

    NASA Astrophysics Data System (ADS)

    Cifelli, R.; Johnson, L. E.; White, A. B.

    2014-12-01

    Advancements in monitoring and prediction of precipitation and severe storms can provide significant benefits for water resource managers, allowing them to mitigate flood damage risks, capture additional water supplies and offset drought impacts, and enhance ecosystem services. A case study for the San Francisco Bay area provides the context for quantification of the benefits of an Advanced Quantitative Precipitation Information (AQPI) system. The AQPI builds off more than a decade of NOAA research and applications of advanced precipitation sensors, data assimilation, numerical models of storms and storm runoff, and systems integration for real-time operations. An AQPI would dovetail with the current National Weather Service forecast operations to provide higher resolution monitoring of rainfall events and longer lead time forecasts. A regional resource accounting approach has been developed to quantify the incremental benefits assignable to the AQPI system; these benefits total to $35 M/yr in the 9 county Bay region. Depending on the jurisdiction large benefits for flood damage avoidance may accrue for locations having dense development in flood plains. In other locations forecst=based reservoir operations can increase reservoir storage for water supplies. Ecosystem services benefits for fisheries may be obtained from increased reservoir storage and downstream releases. Benefits in the transporation sectors are associated with increased safety and avoided delays. Compared to AQPI system implementation and O&M costs over a 10 year operations period, a benefit - cost (B/C) ratio is computed which ranges between 2.8 to 4. It is important to acknowledge that many of the benefits are dependent on appropriate and adequate response by the hazards and water resources management agencies and citizens.

  8. Dietary nitrate reduces skeletal muscle oxygenation response to physical exercise: a quantitative muscle functional MRI study

    PubMed Central

    Bentley, Rachel; Gray, Stuart R.; Schwarzbauer, Christian; Dawson, Dana; Frenneaux, Michael; He, Jiabao

    2014-01-01

    Abstract Dietary inorganic nitrate supplementation (probably via conversion to nitrite) increases skeletal muscle metabolic efficiency. In addition, it may also cause hypoxia‐dependent vasodilation and this has the potential to augment oxygen delivery to exercising skeletal muscle. However, direct evidence for the latter with spatial localization to exercising muscle groups does not exist. We employed quantitative functional MRI (fMRI) to characterize skeletal muscle oxygen utilization and replenishment by assessment of tissue oxygenation maximal change and recovery change, respectively. Eleven healthy subjects were enrolled, of whom 9 (age 33.3 ± 4.4 years, five males) completed the study. Each subject took part in three MRI visits, with dietary nitrate (7cl concentrated beetroot juice) consumed before the third visit. During each visit fMRIs were conducted concurrently with plantar flexion exercise at workloads of 15% and 25% maximum voluntary contraction (MVC). No significant changes were found between visits 1 and 2 in the fMRI measures. A decrease in maximal change was found at 15% MVC in soleus between visits 2 and 3 (5.12 ± 2.36 to 2.55 ± 1.42, P = 0.004) and between visits 1 and 3 (4.43 ± 2.12 to 2.55 ± 1.42, P = 0.043), but not at 25% MVC or within gastrocnemius. There was no difference in recovery change between visits. We found that dietary nitrate supplementation reduces tissue oxygenation alterations during physical exercise in skeletal muscle. This effect is more prominent in muscles with predominantly type 1 fibers and at lower workloads. This indicates that in healthy subjects dietary nitrate predominantly affects skeletal muscle energy efficiency with no change in oxygen delivery. PMID:25052493

  9. Robust quantitative parameter estimation by advanced CMP measurements for vadose zone hydrological studies

    NASA Astrophysics Data System (ADS)

    Koyama, C.; Wang, H.; Khuut, T.; Kawai, T.; Sato, M.

    2015-12-01

    Soil moisture plays a crucial role in the understanding of processes in the vadose zone hydrology. In the last two decades ground penetrating radar (GPR) has been widely discussed has nondestructive measurement technique for soil moisture data. Especially the common mid-point (CMP) technique, which has been used in both seismic and GPR surveys to investigate the vertical velocity profiles, has a very high potential for quantitaive obervsations from the root zone to the ground water aquifer. However, the use is still rather limited today and algorithms for robust quantitative paramter estimation are lacking. In this study we develop an advanced processing scheme for operational soil moisture reetrieval at various depth. Using improved signal processing, together with a semblance - non-normalized cross-correlation sum combined stacking approach and the Dix formula, the interval velocities for multiple soil layers are obtained from the RMS velocities allowing for more accurate estimation of the permittivity at the reflecting point. Where the presence of a water saturated layer, like a groundwater aquifer, can be easily identified by its RMS velocity due to the high contrast compared to the unsaturated zone. By using a new semi-automated measurement technique the acquisition time for a full CMP gather with 1 cm intervals along a 10 m profile can be reduced significantly to under 2 minutes. The method is tested and validated under laboratory conditions in a sand-pit as well as on agricultural fields and beach sand in the Sendai city area. Comparison between CMP estimates and TDR measurements yield a very good agreement with RMSE of 1.5 Vol.-%. The accuracy of depth estimation is validated with errors smaller than 2%. Finally, we demonstrate application of the method in a test site in semi-arid Mongolia, namely the Orkhon River catchment in Bulgan, using commercial 100 MHz and 500 MHz RAMAC GPR antennas. The results demonstrate the suitability of the proposed method for

  10. In vitro remineralization of enamel by polymeric amorphous calcium phosphate composite: Quantitative micro-radiographic study

    PubMed Central

    Langhorst, S.E.; O'Donnell, J.N.R.; Skrtic, D.

    2009-01-01

    Objective: This study explores the efficacy of an experimental orthodontic amorphous calcium phosphate (ACP) composite to remineralize in vitro subsurface enamel lesions microradiographically similar to those seen in early caries. Methods: Lesions were artificially created in extracted human molars. Single tooth sections a minimum of 120 μm thick were cut and individually placed in holders exposing only the carious enamel surface. The exposed surfaces were either left untreated (control) or coated with a 1 mm thick layer of the experimental ACP composite (mass fraction 40 % zirconiahybridized ACP and 60 % photo-activated resin), or a commercial fluoride-releasing orthodontic cement. The composite-coated sections were then photo-cured and microradiographic images were taken of all three groups of specimens before the treatment. Specimens were then cyclically immersed in demineralizing and remineralizing solutions for one month at 37 °C to simulate the pH changes occurring in the oral environment. Microradiographs of all specimens were taken before and after treatment. Results: Quantitative digital image analysis of matched areas from the contact microradiographs taken before and after treatment indicated higher mineral recovery with ACP composites compared to the commercial orthodontic F-releasing cement (14.4 % vs. 4.3 %, respectively), while the control specimens showed an average of 55.4 % further demineralization. Significance: Experimental ACP composite efficiently established mineral ion transfer throughout the body of the lesions and restored the mineral lost due to acid attack. It can be considered a useful adjuvant for the control of caries in orthodontic applications. PMID:19215975

  11. Effects of methylmercury on muscarinic receptors in the mouse brain: A quantitative autoradiographic study

    SciTech Connect

    Lee, Haesung; Yee, S.; Geddes, J.; Choi, Byung, H. Univ. of California, Irvine )

    1991-03-11

    Methylmercury (MeHg) is reported to inhibit several stages of cholinergic neurotransmission in brain tissue in-vitro and in-vivo. To examine whether or not behavioral disturbances and/or selective vulnerability of specific neuronal groups in MeHg poisoning may be related to MeHg effects on cholinergic receptors in specific regions of the brain, the density and distribution of muscarinic receptors in the brains of C57BL/6J mice were determined following repeated injections of 5 mg/kg of methylmercuric chloride (MMC). The receptor densities in six cortical laminae of seven cerebral cortical regions, hippocampus and striatum were quantitated by computer-assisted imaging system following in-vitro labeling with ({sup 3}H)-pirenzepine (M1) and ({sup 3}H)N-methyl scopolamine (M2). The results showed heterogeneous distribution of M1 and M2 sites in different regions of the brain, and significant reduction in the density of both receptor subtypes following MeHg poisoning in many cortical and subcortical regions. However, the changes in the density were variable in different laminae even in the same cortical regions. Prominent reductions in M1 densities were noted in the temporal and entorhinal cortices, CA3 and hilar regions of the hippocampus as compared to control, whereas the reduction in M2 receptor density was most prominently noted in the frontal, perirhinal and entorhinal cortices, and CA1 and hilar regions of the hippocampus. Thus, it is apparent that MeHg significantly affects muscarinic receptors in the mouse brain, and that these data when used in conjunction with immunocytochemical and other morphological studies would provide further insights into the mechanisms of neurotoxic effects of MeHg.

  12. A Genome-Wide Association Study Identifies Protein Quantitative Trait Loci (pQTLs)

    PubMed Central

    Corsi, Anna-Maria; Stevens, Kara; Rafferty, Ian; Lauretani, Fulvio; Murray, Anna; Gibbs, J. Raphael; Paolisso, Giuseppe; Rafiq, Sajjad; Simon-Sanchez, Javier; Lango, Hana; Scholz, Sonja; Weedon, Michael N.; Arepalli, Sampath; Rice, Neil; Washecka, Nicole; Hurst, Alison; Britton, Angela; Henley, William; van de Leemput, Joyce; Li, Rongling; Newman, Anne B.; Tranah, Greg; Harris, Tamara; Panicker, Vijay; Dayan, Colin; Bennett, Amanda; McCarthy, Mark I.; Ruokonen, Aimo; Jarvelin, Marjo-Riitta; Guralnik, Jack; Bandinelli, Stefania; Frayling, Timothy M.; Singleton, Andrew; Ferrucci, Luigi

    2008-01-01

    There is considerable evidence that human genetic variation influences gene expression. Genome-wide studies have revealed that mRNA levels are associated with genetic variation in or close to the gene coding for those mRNA transcripts – cis effects, and elsewhere in the genome – trans effects. The role of genetic variation in determining protein levels has not been systematically assessed. Using a genome-wide association approach we show that common genetic variation influences levels of clinically relevant proteins in human serum and plasma. We evaluated the role of 496,032 polymorphisms on levels of 42 proteins measured in 1200 fasting individuals from the population based InCHIANTI study. Proteins included insulin, several interleukins, adipokines, chemokines, and liver function markers that are implicated in many common diseases including metabolic, inflammatory, and infectious conditions. We identified eight Cis effects, including variants in or near the IL6R (p = 1.8×10−57), CCL4L1 (p = 3.9×10−21), IL18 (p = 6.8×10−13), LPA (p = 4.4×10−10), GGT1 (p = 1.5×10−7), SHBG (p = 3.1×10−7), CRP (p = 6.4×10−6) and IL1RN (p = 7.3×10−6) genes, all associated with their respective protein products with effect sizes ranging from 0.19 to 0.69 standard deviations per allele. Mechanisms implicated include altered rates of cleavage of bound to unbound soluble receptor (IL6R), altered secretion rates of different sized proteins (LPA), variation in gene copy number (CCL4L1) and altered transcription (GGT1). We identified one novel trans effect that was an association between ABO blood group and tumour necrosis factor alpha (TNF-alpha) levels (p = 6.8×10−40), but this finding was not present when TNF-alpha was measured using a different assay , or in a second study, suggesting an assay-specific association. Our results show that protein levels share some of the features of the genetics of gene expression. These

  13. CCQM Pilot Study CCQM-P140: Quantitative surface analysis of multi-element alloy films

    NASA Astrophysics Data System (ADS)

    Kim, Kyung Joong; Jang, Jong Shik; Kim, An Soon; Suh, Jung Ki; Chung, Yong-Duck; Hodoroaba, Vasile-Dan; Wirth, Thomas; Unger, Wolfgang; Kang, Hee Jae; Popov, Oleg; Popov, Inna; Kuselman, Ilya; Lee, Yeon Hee; Sykes, David E.; Wang, Meiling; Wang, Hai; Ogiwara, Toshiya; Nishio, Mitsuaki; Tanuma, Shigeo; Simons, David; Szakal, Christopher; Osborn, William; Terauchi, Shinya; Ito, Mika; Kurokawa, Akira; Fujimoto, Toshiyuki; Jordaan, Werner; Jeong, Chil Seong; Havelund, Rasmus; Spencer, Steve; Shard, Alex; Streeck, Cornelia; Beckhoff, Burkhard; Eicke, Axel; Terborg, Ralf

    2015-01-01

    A pilot study for a quantitative surface analysis of multi-element alloy films has been performed by the Surface Analysis Working Group (SAWG) of the Consultative Committee for Amount of Substance (CCQM). The aim of this pilot study is to evaluate a protocol for a key comparison to demonstrate the equivalence of measures by National Metrology Institutes (NMIs) and Designated Institutes (DI) for the mole fractions of multi-element alloy films. A Cu(In,Ga)Se2 (CIGS) film with non-uniform depth distribution was chosen as a representative multi-element alloy film. The mole fractions of the reference and the test CIGS films were certified by isotope dilution—inductively coupled plasma/mass spectrometry. A total number counting (TNC) method was used as a method to determine the signal intensities of the constituent elements acquired in SIMS, XPS and AES depth profiling. TNC method is comparable with the certification process because the certified mole fractions are the average values of the films. The mole fractions of the CIGS films were measured by Secondary Ion Mass Spectrometry (SIMS), Auger Electron Spectroscopy (AES), X-ray Photoelectron Spectroscopy (XPS), X-Ray Fluorescence (XRF) Analysis and Electron Probe Micro Analysis (EPMA) with Energy Dispersive X-ray Spectrometry (EDX). Fifteen laboratories from eight NMIs, one DI, and six non-NMIs participated in this pilot study. The average mole fractions of the reported data showed relative standard deviations from 5.5 % to 6.8 % and average relative expanded uncertainties in the range from 4.52 % to 4.86 % for the four test CIGS specimens. These values are smaller than those in the key comparison CCQM-K67 for the measurement of mole fractions of Fe-Ni alloy films. As one result it can be stated that SIMS, XPS and AES protocols relying on the quantification of CIGS films using the TNC method are mature to be used in a CCQM key comparison. Main text. To reach the main text of this paper, click on Final Report. The

  14. A quantitative approach for estimating exposure to pesticides in the Agricultural Health Study.

    PubMed

    Dosemeci, Mustafa; Alavanja, Michael C R; Rowland, Andrew S; Mage, David; Zahm, Shelia Hoar; Rothman, Nathaniel; Lubin, Jay H; Hoppin, Jane A; Sandler, Dale P; Blair, Aaron

    2002-03-01

    We developed a quantitative method to estimate long-term chemical-specific pesticide exposures in a large prospective cohort study of more than 58000 pesticide applicators in North Carolina and Iowa. An enrollment questionnaire was administered to applicators to collect basic time- and intensity-related information on pesticide exposure such as mixing condition, duration and frequency of application, application methods and personal protective equipment used. In addition, a detailed take-home questionnaire was administered to collect further intensity-related exposure information such as maintenance or repair of mixing and application equipment, work practices and personal hygiene. More than 40% of the enrolled applicators responded to this detailed take-home questionnaire. Two algorithms were developed to identify applicators' exposure scenarios using information from the enrollment and take-home questionnaires separately in the calculation of subject-specific intensity of exposure score to individual pesticides. The 'general algorithm' used four basic variables (i.e. mixing status, application method, equipment repair status and personal protective equipment use) from the enrollment questionnaire and measurement data from the published pesticide exposure literature to calculate estimated intensity of exposure to individual pesticides for each applicator. The 'detailed' algorithm was based on variables in the general algorithm plus additional exposure information from the take-home questionnaire, including types of mixing system used (i.e. enclosed or open), having a tractor with enclosed cab and/or charcoal filter, frequency of washing equipment after application, frequency of replacing old gloves, personal hygiene and changing clothes after a spill. Weighting factors applied in both algorithms were estimated using measurement data from the published pesticide exposure literature and professional judgment. For each study subject, chemical-specific lifetime

  15. The relationship between international trade and non-nutritional health outcomes: A systematic review of quantitative studies.

    PubMed

    Burns, Darren K; Jones, Andrew P; Suhrcke, Marc

    2016-03-01

    Markets throughout the world have been reducing barriers to international trade and investment in recent years. The resulting increases in levels of international trade and investment have subsequently generated research interest into the potential population health impact. We present a systematic review of quantitative studies investigating the relationship between international trade, foreign direct investment and non-nutritional health outcomes. Articles were systematically collected from the SCOPUS, PubMed, EconLit and Web of Science databases. Due to the heterogeneous nature of the evidence considered, the 16 included articles were subdivided into individual level data analyses, selected country analyses and international panel analyses. Articles were then quality assessed using a tool developed as part of the project. Nine of the studies were assessed to be high quality, six as medium quality, and one as low quality. The evidence from the quantitative literature suggests that overall, there appears to be a beneficial association between international trade and population health. There was also evidence of the importance of foreign direct investment, yet a lack of research considering the direction of causality. Taken together, quantitative research into the relationship between trade and non-nutritional health indicates trade to be beneficial, yet this body of research is still in its infancy. Future quantitative studies based on this foundation will provide a stronger basis on which to inform relevant national and international institutions about the health consequences of trade policies. PMID:26820112

  16. Studying Biology to Understand Risk: Dosimetry Models and Quantitative Adverse Outcome Pathways

    EPA Science Inventory

    Confidence in the quantitative prediction of risk is increased when the prediction is based to as great an extent as possible on the relevant biological factors that constitute the pathway from exposure to adverse outcome. With the first examples now over 40 years old, physiologi...

  17. Recidivism, Disciplinary History, and Institutional Adjustment: A Quantitative Study Examining Correctional Education Programs

    ERIC Educational Resources Information Center

    Flamer, Eric, Sr.

    2012-01-01

    Establishing college-degree programs for prison inmates is an evidence-based effective instructional strategy in reducing recidivism. Evaluating academic arenas as a resource to improve behavior and levels of functioning within correctional facilities is a necessary component of inmate academic programs. The purpose of this quantitative,…

  18. Implementing Response to Intervention in Title I Elementary Schools: A Quantitative Study of Teacher Response Relationships

    ERIC Educational Resources Information Center

    Webster, Katina F.

    2012-01-01

    General educators and special educators in Title I elementary schools perceive the relationships between principles of RTI and their state RTI framework, the implementation of RTI, and professional development received in RTI differently. A quantitative survey-based research methodology was employed including the use of Cronbach's alpha to…

  19. Quantitative in situ hybridization for the study of gene expression at the regional and cellular levels.

    PubMed

    Le Moine, Catherine

    2003-08-01

    Quantitative in situ hybridization allows measurement of mRNA level modifications in a variety of experimental conditions. This analysis may be performed both at the regional anatomical and cellular levels by densitometry, neuronal counting and silver grain measurements. PMID:18428577

  20. A review of marine geomorphometry, the quantitative study of the seafloor

    NASA Astrophysics Data System (ADS)

    Lecours, Vincent; Dolan, Margaret F. J.; Micallef, Aaron; Lucieer, Vanessa L.

    2016-08-01

    Geomorphometry, the science of quantitative terrain characterization, has traditionally focused on the investigation of terrestrial landscapes. However, the dramatic increase in the availability of digital bathymetric data and the increasing ease by which geomorphometry can be investigated using geographic information systems (GISs) and spatial analysis software has prompted interest in employing geomorphometric techniques to investigate the marine environment. Over the last decade or so, a multitude of geomorphometric techniques (e.g. terrain attributes, feature extraction, automated classification) have been applied to characterize seabed terrain from the coastal zone to the deep sea. Geomorphometric techniques are, however, not as varied, nor as extensively applied, in marine as they are in terrestrial environments. This is at least partly due to difficulties associated with capturing, classifying, and validating terrain characteristics underwater. There is, nevertheless, much common ground between terrestrial and marine geomorphometry applications and it is important that, in developing marine geomorphometry, we learn from experiences in terrestrial studies. However, not all terrestrial solutions can be adopted by marine geomorphometric studies since the dynamic, four-dimensional (4-D) nature of the marine environment causes its own issues throughout the geomorphometry workflow. For instance, issues with underwater positioning, variations in sound velocity in the water column affecting acoustic-based mapping, and our inability to directly observe and measure depth and morphological features on the seafloor are all issues specific to the application of geomorphometry in the marine environment. Such issues fuel the need for a dedicated scientific effort in marine geomorphometry.This review aims to highlight the relatively recent growth of marine geomorphometry as a distinct discipline, and offers the first comprehensive overview of marine geomorphometry to date

  1. Pressure ulcer prevention algorithm content validation: a mixed-methods, quantitative study.

    PubMed

    van Rijswijk, Lia; Beitz, Janice M

    2015-04-01

    Translating pressure ulcer prevention (PUP) evidence-based recommendations into practice remains challenging for a variety of reasons, including the perceived quality, validity, and usability of the research or the guideline itself. Following the development and face validation testing of an evidence-based PUP algorithm, additional stakeholder input and testing were needed. Using convenience sampling methods, wound care experts attending a national wound care conference and a regional wound ostomy continence nursing (WOCN) conference and/or graduates of a WOCN program were invited to participate in an Internal Review Board-approved, mixed-methods quantitative survey with qualitative components to examine algorithm content validity. After participants provided written informed consent, demographic variables were collected and participants were asked to comment on and rate the relevance and appropriateness of each of the 26 algorithm decision points/steps using standard content validation study procedures. All responses were anonymous. Descriptive summary statistics, mean relevance/appropriateness scores, and the content validity index (CVI) were calculated. Qualitative comments were transcribed and thematically analyzed. Of the 553 wound care experts invited, 79 (average age 52.9 years, SD 10.1; range 23-73) consented to participate and completed the study (a response rate of 14%). Most (67, 85%) were female, registered (49, 62%) or advanced practice (12, 15%) nurses, and had > 10 years of health care experience (88, 92%). Other health disciplines included medical doctors, physical therapists, nurse practitioners, and certified nurse specialists. Almost all had received formal wound care education (75, 95%). On a Likert-type scale of 1 (not relevant/appropriate) to 4 (very relevant and appropriate), the average score for the entire algorithm/all decision points (N = 1,912) was 3.72 with an overall CVI of 0.94 (out of 1). The only decision point/step recommendation

  2. Quantitative synchrotron X-ray fluorescence study of the penetration of transferrin-conjugated gold nanoparticles inside model tumour tissues

    NASA Astrophysics Data System (ADS)

    Liu, Tianqing; Kempson, Ivan; de Jonge, Martin; Howard, Daryl L.; Thierry, Benjamin

    2014-07-01

    The next generation of therapeutic nanoparticles in the treatment of cancer incorporate specific targeting. There is implicit importance in understanding penetration of targeted nanomedicines within tumour tissues via accurate and quantitative temporospatial measurements. In this study we demonstrate the potential of state-of-the-art synchrotron X-ray fluorescence microscopy (XFM) to provide such insights. To this end, quantitative mapping of the distribution of transferrin-conjugated gold nanoparticles inside multicellular tumour spheroids was achieved using XFM and compared with qualitative data obtained using reflectance confocal microscopy. Gold nanoparticles conjugated with human transferrin with a narrow size-distribution and high binding affinity to tumour cells were prepared as confirmed by cellular uptake studies performed on 2D monolayers. Although the prepared 100 nm transferrin-conjugated gold nanoparticles had high targeting capability to cancer cells, penetration inside multicellular spheroids was limited even after 48 hours as shown by the quantitative XFM measurements. The rapid, quantitative and label-free nature of state-of-the-art synchrotron XFM make it an ideal technology to provide the structure-activity relationship understanding urgently required for developing the next generation of immuno-targeted nanomedicines.

  3. Technology Resource, Distribution, and Development Characteristics of Global Influenza Virus Vaccine: A Patent Bibliometric Analysis.

    PubMed

    Chen, Ning; Liu, Yun; Cheng, Yijie; Liu, Long; Yan, Zhe; Tao, Lixin; Guo, Xiuhua; Luo, Yanxia; Yan, Aoshuang

    2015-01-01

    Influenza virus vaccine (IVV) is a promising research domain that is closely related to global health matters, which has been acknowledged not only by scientists and technology developers, but also by policy-makers. Meanwhile, patents encompass valuable technological information and reflect the latest technological inventions as well as the innovative capability of a nation. However, little research has examined this up-and-coming research field using patent bibliometric method. Thus, this paper (a) designs the technology classification system and search strategy for the identification of IVV; and (b) presents a longitudinal analysis of the global IVV development based on the European Patent Office (EPO) patents. Bibliometric analysis is used to rank countries, institutions, inventors and technology subfields contributing to IVV technical progress. The results show that the global trends of IVV are a multi-developing feature of variety but an uneven technical resource distribution. Although the synthetic peptide vaccine is a comparatively young field, it already demonstrates the powerful vitality and the enormous development space. With the worldwide competition increasing, all nations especially China should be looking to increase devotion, enhance capability and regard effectiveness of technological innovation. PMID:26372160

  4. A new bibliometric index based on the shape of the citation distribution.

    PubMed

    Lando, Tommaso; Bertoli-Barsotti, Lucio

    2014-01-01

    In order to improve the h-index in terms of its accuracy and sensitivity to the form of the citation distribution, we propose the new bibliometric index [symbol in text]. The basic idea is to define, for any author with a given number of citations, an "ideal" citation distribution which represents a benchmark in terms of number of papers and number of citations per publication, and to obtain an index which increases its value when the real citation distribution approaches its ideal form. The method is very general because the ideal distribution can be defined differently according to the main objective of the index. In this paper we propose to define it by a "squared-form" distribution: this is consistent with many popular bibliometric indices, which reach their maximum value when the distribution is basically a "square". This approach generally rewards the more regular and reliable researchers, and it seems to be especially suitable for dealing with common situations such as applications for academic positions. To show the advantages of the [symbol in text]-index some mathematical properties are proved and an application to real data is proposed. PMID:25542026

  5. Technology Resource, Distribution, and Development Characteristics of Global Influenza Virus Vaccine: A Patent Bibliometric Analysis

    PubMed Central

    Liu, Long; Yan, Zhe; Tao, Lixin; Guo, Xiuhua; Luo, Yanxia; Yan, Aoshuang

    2015-01-01

    Influenza virus vaccine (IVV) is a promising research domain that is closely related to global health matters, which has been acknowledged not only by scientists and technology developers, but also by policy-makers. Meanwhile, patents encompass valuable technological information and reflect the latest technological inventions as well as the innovative capability of a nation. However, little research has examined this up-and-coming research field using patent bibliometric method. Thus, this paper (a) designs the technology classification system and search strategy for the identification of IVV; and (b) presents a longitudinal analysis of the global IVV development based on the European Patent Office (EPO) patents. Bibliometric analysis is used to rank countries, institutions, inventors and technology subfields contributing to IVV technical progress. The results show that the global trends of IVV are a multi-developing feature of variety but an uneven technical resource distribution. Although the synthetic peptide vaccine is a comparatively young field, it already demonstrates the powerful vitality and the enormous development space. With the worldwide competition increasing, all nations especially China should be looking to increase devotion, enhance capability and regard effectiveness of technological innovation. PMID:26372160

  6. Comparative Performance of Adult Social Care Research, 1996–2011: A Bibliometric Assessment

    PubMed Central

    Campbell, David; Côté, Grégoire; Grant, Jonathan; Knapp, Martin; Mehta, Anji; Morgan Jones, Molly

    2016-01-01

    Decision makers in adult social care are increasingly interested in using evidence from research to support or shape their decisions. The scope and nature of the current landscape of adult social care research (ASCR) need to be better understood. This paper provides a bibliometric assessment of ASCR outputs from 1996 to 2011. ASCR papers were retrieved using three strategies: from key journals; using keywords and noun phrases; and from additional papers preferentially citing or being cited by other ASCR papers. Overall, 195,829 ASCR papers were identified in the bibliographic database Scopus, of which 16 per cent involved at least one author from the UK. The UK output increased 2.45-fold between 1996 and 2011. Among selected countries, those with greater research intensity in ASCR generally had higher citation impact, such as the USA, UK, Canada and the Netherlands. The top five UK institutions in terms of volume of papers in the UK accounted for 26 per cent of total output. We conclude by noting the limitations to bibliometric analysis of ASCR and examine how such analysis can support the strategic development of the field. PMID:27559228

  7. On the origins and the historical roots of the Higgs boson research from a bibliometric perspective

    NASA Astrophysics Data System (ADS)

    Barth, A.; Marx, W.; Bornmann, L.; Mutz, R.

    2014-06-01

    The subject of our present paper is the analysis of the origins or historical roots of the Higgs boson research from a bibliometric perspective, using a segmented regression analysis in combination with a method named reference publication year spectroscopy (RPYS). Our analysis is based on the references cited in the Higgs boson publications published since 1974. The objective of our analysis consists of identifying specific individual publications in the Higgs boson research context to which the scientific community frequently had referred to. We are interested in seminal works which contributed to a high extent to the discovery of the Higgs boson. Our results show that researchers in the Higgs boson field preferably refer to more recently published papers —particularly papers published since the beginning of the sixties. For example, our analysis reveals seven major contributions which appeared within the sixties: Englert and Brout (1964), Higgs (1964, 2 papers), and Guralnik et al. (1964) on the Higgs mechanism as well as Glashow (1961), Weinberg (1967), and Salam (1968) on the unification of weak and electromagnetic interaction. Even if the Nobel Prize award highlights the outstanding importance of the work of Peter Higgs and Francois Englert, bibliometrics offer the additional possibility of getting hints to other publications in this research field (especially to historical publications), which are of vital importance from the expert point of view.

  8. Quantitative study of fretting fatigue damage in shot peened titanium-aluminum-vanadium

    NASA Astrophysics Data System (ADS)

    Martinez, Sonia A.

    Fretting fatigue damage has been known to be the origin of premature failure in some of the aerospace engine components. The blade/disk assemblies, for example have been particularly susceptible to fretting induced failure. Several nondestructive evaluation techniques are being used to detect the cracks due to fretting fatigue damage. Although partial success has been achieved in detection of cracks, research is lacking in the area of detection of precursors to the development of cracks due fretting fatigue damage. The goal of the research presented in this thesis is to develop a methodology based on x-ray diffraction residual stress measurements for quantitative nondestructive characterization of accumulated fretting fatigue damage. To achieve the goal a systematic experimental study of the characteristics of the residual stress due to surface treatments of shot peening (SP), Laser Shock Peening (LSP) and Low Plasticity Burnishing (LPB), used in the aerospace industry was conducted. The residual stress in LSP and LPB was found to be complex involving shear stress and spatial non-uniformity. On the other hand in shot peening it was found to be least complex. More over it is the most cost effective and hence often used surface treatment in the industry. In order to gain an understanding of the effect of shot peening parameters on the fretting fatigue life, experiments were conducted on samples with four different peening intensities (0, 4, 7 and 10 A) and two surface coverage (100% and 400%). It was observed that the fretting fatigue life increases with the increasing peening intensity, and increase in surface coverage beyond 100% has virtually no effect. Scanning Electron Microscopic (SEM) observation of fractured surface was utilized to identify crack initiation. On all of the fretting fatigued specimens relaxation of residual stress was observed and it increased with increasing number of cycles. A complete relaxation was observed before failure. To obtain an

  9. Quantitative studies of kinetic effects in direct- and indirect-drive Inertial Confinement Fusion implosions

    NASA Astrophysics Data System (ADS)

    Rinderknecht, Hans

    2013-10-01

    A comprehensive set of experiments using shock-driven implosions has been conducted to quantitatively study kinetic effects by exploring deviations from hydrodynamic behavior in plasmas relevant to inertial confinement fusion (ICF). Two types of targets were imploded at OMEGA to create ~10 keV, ~1022 cm-3 plasmas with conditions comparable to the incipient hotspot in ignition designs: thin-glass targets filled with mixtures of D2 and 3He gas; and thin deuterated-plastic shells filled with 3He. In the thin-glass experiments, the gas pressure was varied from 1 to 25 atm to scan the ion-mean-free path in the plasma at shock burn. The observed nuclear yields and temperatures deviated more strongly from hydrodynamic predictions as the ion-mean-free path increased to the order of the plasma size. This result provides the first direct experimental evidence how kinetic effects impact yields and ion temperature. The ratio of D to 3He was also varied while maintaining the fuel mass density. As the D fraction was reduced, the DD and D3He fusion products displayed an anomalous yield reduction. Separation of the D and 3He ion species across the strong (Mach ~10) shock-front will be discussed as the likely cause of this result. Finally, thin-CD shells filled with 3He produced significantly more D3He-protons when imploded than is explained by hydrodynamic mix models. This result suggests a kinetic form of mix dominates at the strongly-shocked shell-gas interface. This work was performed in collaboration with C. Li, M. Rosenberg, A. Zylstra, H. Sio, M. Gatu Johnson, F. Séguin, J. Frenje, and R. Petrasso (MIT), V. Glebov, C. Stoeckl, J. Delettrez, and C. Sangster (LLE), J. Pino, P. Amendt, C. Bellei, and S. Wilks (LLNL), G. Kagan, N. Hoffmann and K. Molvig (LANL), and A. Nikroo (GA) and was supported in part by the NLUF, FSC/UR, U.S. DOE, LLNL and LLE.

  10. Quantitative study of the deformation at Southern Explorer Ridge using high-resolution bathymetric data

    NASA Astrophysics Data System (ADS)

    Deschamps, Anne; Tivey, Maurice; Embley, Robert W.; Chadwick, William W.

    2007-07-01

    We present preliminary results of a morphological study of the summit of the Southern Explorer Ridge (SER). The SER is an inflated intermediate-rate spreading center located in the northeast Pacific off the West coast of Canada, that hosts a large hydrothermal vent complex known as "Magic Mountain". A quantitative assessment of faulting on the axial summit graben floor close to the ridge summit is accomplished through the analysis of high-resolution, near-bottom, bathymetric data. These data were acquired using a multibeam system mounted on an autonomous underwater vehicle operated a few tens meters above the seafloor. Structural mapping reveals numerous subvertical fissures and normal faults that nucleated from tension fissures. The ratio between the length and the maximum scarp height of normal faults is not constant contrary to what is generally observed on subaerial faults, highlighting the probable importance of fault segment linkage and fault growth processes within the relatively thin brittle layer. Populations of small faults exhibit an exponential size-frequency distribution that reflects the importance of linkage in the fault growth history and the relatively large amount of tectonic strain (3.7 to 18.4%) accommodated by the normal faults. We propose that the 500 to 600-m wide and ˜ 60-m deep asymmetric axial summit graben of the SER formed due to magma chamber deflation as well as normal faulting that initiated on the present eastern border of the graben. We find a well-defined geographic distribution in the types of lava flows, which indicates a general decrease of the eruption rate through time. We also find that the "Magic Mountain" hydrothermal field is located in the vicinity of the large eastern axial summit graben bounding fault whose dimensions suggest it may reach to the brittle ductile-transition depth. This fault likely has provided an efficient physical pathway for fluids from the subsurface to the seafloor for a significant period of time

  11. Quantitative x-ray radiography using grating interferometry: a feasibility study

    NASA Astrophysics Data System (ADS)

    Wang, Zhentian; Stampanoni, Marco

    2013-10-01

    X-ray grating interferometry is a promising tool for medical imaging because of its capability of providing additional and complementary information to conventional absorption-based methods. This technology can simultaneously measure absorption, differential phase and small-angle scattering signals from the sample, significantly improving the diagnostic content. In this work, we present a method which uses the image (dubbed the R image) obtained by taking the ratio of the absorption and small-angle scattering signals to gain quantitative insight from a radiographic x-ray projection. We demonstrate that with the help of the R image we can successfully distinguish among different (light-Z) plastic materials, which are usually used to mimic soft tissues. Two potential applications in medical imaging, such as quantitative x-ray radiography and volumetric breast density estimation, are demonstrated.

  12. QUANTITATIVE STUDIES OF THERMAL SHOCK IN CERAMICS BASED ON A NOVEL TEST TECHNIQUE

    SciTech Connect

    Faber, K. T.; Huang, M. D.; Evans, A. G.

    1981-05-01

    A thermal shock test has been designed which permits the thermal fracture resistance and the mechanical strength of brittle materials to be quantitatively correlated. Thermal shock·results for two materials, Al{sub 2}O{sub 3} and SiC, have been accurately predicted from biaxial strength measurements and a transient thermal stress analysis (performed using a finite element method). General implications for the prediction of thermal shock resistance, with special reference to ceramic components, are discussed.

  13. Genome-wide association studies of quantitatively measured skin, hair, and eye pigmentation in four European populations.

    PubMed

    Candille, Sophie I; Absher, Devin M; Beleza, Sandra; Bauchet, Marc; McEvoy, Brian; Garrison, Nanibaa' A; Li, Jun Z; Myers, Richard M; Barsh, Gregory S; Tang, Hua; Shriver, Mark D

    2012-01-01

    Pigmentation of the skin, hair, and eyes varies both within and between human populations. Identifying the genes and alleles underlying this variation has been the goal of many candidate gene and several genome-wide association studies (GWAS). Most GWAS for pigmentary traits to date have been based on subjective phenotypes using categorical scales. But skin, hair, and eye pigmentation vary continuously. Here, we seek to characterize quantitative variation in these traits objectively and accurately and to determine their genetic basis. Objective and quantitative measures of skin, hair, and eye color were made using reflectance or digital spectroscopy in Europeans from Ireland, Poland, Italy, and Portugal. A GWAS was conducted for the three quantitative pigmentation phenotypes in 176 women across 313,763 SNP loci, and replication of the most significant associations was attempted in a sample of 294 European men and women from the same countries. We find that the pigmentation phenotypes are highly stratified along axes of European genetic differentiation. The country of sampling explains approximately 35% of the variation in skin pigmentation, 31% of the variation in hair pigmentation, and 40% of the variation in eye pigmentation. All three quantitative phenotypes are correlated with each other. In our two-stage association study, we reproduce the association of rs1667394 at the OCA2/HERC2 locus with eye color but we do not identify new genetic determinants of skin and hair pigmentation supporting the lack of major genes affecting skin and hair color variation within Europe and suggesting that not only careful phenotyping but also larger cohorts are required to understand the genetic architecture of these complex quantitative traits. Interestingly, we also see that in each of these four populations, men are more lightly pigmented in the unexposed skin of the inner arm than women, a fact that is underappreciated and may vary across the world. PMID:23118974

  14. Bibliometrics: tracking research impact by selecting the appropriate metrics.

    PubMed

    Agarwal, Ashok; Durairajanayagam, Damayanthi; Tatagari, Sindhuja; Esteves, Sandro C; Harlev, Avi; Henkel, Ralf; Roychoudhury, Shubhadeep; Homa, Sheryl; Puchalt, Nicolás Garrido; Ramasamy, Ranjith; Majzoub, Ahmad; Ly, Kim Dao; Tvrda, Eva; Assidi, Mourad; Kesari, Kavindra; Sharma, Reecha; Banihani, Saleem; Ko, Edmund; Abu-Elmagd, Muhammad; Gosalvez, Jaime; Bashiri, Asher

    2016-01-01

    Traditionally, the success of a researcher is assessed by the number of publications he or she publishes in peer-reviewed, indexed, high impact journals. This essential yardstick, often referred to as the impact of a specific researcher, is assessed through the use of various metrics. While researchers may be acquainted with such matrices, many do not know how to use them to enhance their careers. In addition to these metrics, a number of other factors should be taken into consideration to objectively evaluate a scientist's profile as a researcher and academician. Moreover, each metric has its own limitations that need to be considered when selecting an appropriate metric for evaluation. This paper provides a broad overview of the wide array of metrics currently in use in academia and research. Popular metrics are discussed and defined, including traditional metrics and article-level metrics, some of which are applied to researchers for a greater understanding of a particular concept, including varicocele that is the thematic area of this Special Issue of Asian Journal of Andrology. We recommend the combined use of quantitative and qualitative evaluation using judiciously selected metrics for a more objective assessment of scholarly output and research impact. PMID:26806079

  15. Bibliometrics: tracking research impact by selecting the appropriate metrics

    PubMed Central

    Agarwal, Ashok; Durairajanayagam, Damayanthi; Tatagari, Sindhuja; Esteves, Sandro C; Harlev, Avi; Henkel, Ralf; Roychoudhury, Shubhadeep; Homa, Sheryl; Puchalt, Nicolás Garrido; Ramasamy, Ranjith; Majzoub, Ahmad; Ly, Kim Dao; Tvrda, Eva; Assidi, Mourad; Kesari, Kavindra; Sharma, Reecha; Banihani, Saleem; Ko, Edmund; Abu-Elmagd, Muhammad; Gosalvez, Jaime; Bashiri, Asher

    2016-01-01

    Traditionally, the success of a researcher is assessed by the number of publications he or she publishes in peer-reviewed, indexed, high impact journals. This essential yardstick, often referred to as the impact of a specific researcher, is assessed through the use of various metrics. While researchers may be acquainted with such matrices, many do not know how to use them to enhance their careers. In addition to these metrics, a number of other factors should be taken into consideration to objectively evaluate a scientist's profile as a researcher and academician. Moreover, each metric has its own limitations that need to be considered when selecting an appropriate metric for evaluation. This paper provides a broad overview of the wide array of metrics currently in use in academia and research. Popular metrics are discussed and defined, including traditional metrics and article-level metrics, some of which are applied to researchers for a greater understanding of a particular concept, including varicocele that is the thematic area of this Special Issue of Asian Journal of Andrology. We recommend the combined use of quantitative and qualitative evaluation using judiciously selected metrics for a more objective assessment of scholarly output and research impact. PMID:26806079

  16. Contrast enhanced ultrasound with quantitative perfusion analysis for objective characterization of pancreatic ductal adenocarcinoma: A feasibility study.

    PubMed

    D'Onofrio, Mirko; Canestrini, Stefano; Crosara, Stefano; De Robertis, Riccardo; Pozzi Mucelli, Roberto

    2014-03-28

    The aim of this study was to determine whether contrast enhanced ultrasound (CEUS) quantitative perfusion analysis allows an objective characterization of ductal adenocarcinoma (ADK) of the pancreas. Patients with pancreatic ADK underwent CEUS. All examinations were performed on an Acuson S2000 system (Siemens, Erlangen, Germany) after the iv administration of 2.4 mL contrast agent (SonoVue(®), Bracco, Milan, Italy). All lesions were pathologically proved. An operator manually drew different regions of interest within the tumor and the adjacent parenchyma to allow the quantitative perfusion analysis. The mean values of peak of enhancement, time to peak and ascending curve were calculated and compared using the Student's t test. The quantitative perfusion analysis was possible in all lesions. The mean values of the peak of enhancement, time to peak and ascending curve were 17.19%, 7.97 s and 159.52% s within the tumor and 33.57%, 8.89 s and 355.29% s within the adjacent parenchyma. The peak of enhancement and the ascending curve values were significantly different within the tumor and the adjacent parenchyma. Thus, CEUS allows the quantitative perfusion analysis of pancreatic ductal adenocarcinoma. PMID:24765238

  17. Contrast enhanced ultrasound with quantitative perfusion analysis for objective characterization of pancreatic ductal adenocarcinoma: A feasibility study

    PubMed Central

    D’Onofrio, Mirko; Canestrini, Stefano; Crosara, Stefano; Robertis, Riccardo De; Mucelli, Roberto Pozzi

    2014-01-01

    The aim of this study was to determine whether contrast enhanced ultrasound (CEUS) quantitative perfusion analysis allows an objective characterization of ductal adenocarcinoma (ADK) of the pancreas. Patients with pancreatic ADK underwent CEUS. All examinations were performed on an Acuson S2000 system (Siemens, Erlangen, Germany) after the iv administration of 2.4 mL contrast agent (SonoVue®, Bracco, Milan, Italy). All lesions were pathologically proved. An operator manually drew different regions of interest within the tumor and the adjacent parenchyma to allow the quantitative perfusion analysis. The mean values of peak of enhancement, time to peak and ascending curve were calculated and compared using the Student’s t test. The quantitative perfusion analysis was possible in all lesions. The mean values of the peak of enhancement, time to peak and ascending curve were 17.19%, 7.97 s and 159.52% s within the tumor and 33.57%, 8.89 s and 355.29% s within the adjacent parenchyma. The peak of enhancement and the ascending curve values were significantly different within the tumor and the adjacent parenchyma. Thus, CEUS allows the quantitative perfusion analysis of pancreatic ductal adenocarcinoma. PMID:24765238

  18. Bibliometric analysis of scientific publications on waterpipe (narghile, shisha, hookah) tobacco smoking during the period 2003-2012

    PubMed Central

    2014-01-01

    Background Waterpipe tobacco smoking has spread worldwide. However, the evaluation of scientific output in the field of waterpipe tobacco smoking has not been studied yet. The main objectives of this study were to analyze worldwide research output in the waterpipe tobacco smoking field, and to examine the authorship pattern and the citations retrieved from the Scopus database for over a decade. Methods Data from January 1, 2003 through December 31, 2012 were searched for documents with specific words regarding waterpipe tobacco smoking as “keywords” in the title. Scientific output was evaluated based on a methodology developed and used in other bibliometric studies: (a) total and trends of contributions in waterpipe tobacco smoking research between 2003 and 2012; (b) authorship patterns and research productivity; (c) collaboration patterns; (d) the citations received by the publications; and (e) areas of interest of the published papers. Results Worldwide there were 334 publications that met the criteria during the study period. The largest number of publications in waterpipe tobacco smoking were from the United States of America (USA) (33.5%), followed by Lebanon (15.3%), and France (10.5%). The total number of citations at the time of data analysis (October 18, 2013) was 4,352, with an average of 13 citations per document and a median (interquartile range) of 4.0 (1.0–16.0). The h-index of the retrieved documents was 34. The highest h-index by country was 27 for the USA, followed by 20 for Syrian Arab Republic and Lebanon. Conclusions The present data reveal a promising rise and a good start for research activity in the field of waterpipe tobacco smoking. More effort is needed to bridge the gap in waterpipe smoking-based research and to promote better evaluation of waterpipe smoking, risks, health effects, or control services worldwide. PMID:24725483

  19. Bibliometric analysis of scientific publications in transplantation journals from Mainland China, Japan, South Korea and Taiwan between 2006 and 2015

    PubMed Central

    Lyu, Qiu-Ju; Su, Huai-Yu

    2016-01-01

    Objectives The aim of this study is to compare the quantity and quality of scientific publications in transplantation fields that were written by researchers from Mainland China, Japan, South Korea and Taiwan in the East Asia region. Settings East Asia. Participants and outcome measures Articles except editorials, conference abstracts, letters, news and corrections published in 25 transplantation journals from 2006 to 2015 were screened with the Web of Science database. The number of total and annual articles, article types (study design and transplantation site), impact factor, citations and articles in the high-impact journals was determined to assess the quantity and quality of transplantation research from East Asia. The correlation of socioeconomic factors and annual publications was also analysed. Results From 2006 to 2015, there were 47 141 articles published in transplantation journals, of which researchers from Japan published 3694 articles, followed by Mainland China, South Korea and Taiwan with 2778, 1643 and 951 articles, respectively. Similar trends were observed in accumulated impact factor, accumulated citations, articles in the high-impact journals and articles on transplantation site. Publications from Japan had the highest average impact factor and citation, while those from Mainland China had the lowest. Additionally, in terms of study design, authors from Mainland China contributed to most clinical trials and randomised controlled trials, but authors from Japan contributed to most case reports. The annual numbers of articles from Mainland China and South Korea increased linearly (p<0.05), but those from Japan and Taiwan remained stable for the period studied. The annual numbers of articles from Mainland China and South Korea were positively correlated with gross domestic product (p<0.05). Conclusions Transplantation research productivity in East Asia is highly skewed, with gross domestic product having a significant positive correlation

  20. Information Technology Tools Analysis in Quantitative Courses of IT-Management (Case Study: M.Sc.-Tehran University)

    ERIC Educational Resources Information Center

    Eshlaghy, Abbas Toloie; Kaveh, Haydeh

    2009-01-01

    The purpose of this study was to determine the most suitable ICT-based education and define the most suitable e-content creation tools for quantitative courses in the IT-management Masters program. ICT-based tools and technologies are divided in to three categories: the creation of e-content, the offering of e-content, and access to e-content. In…

  1. Exploring the brain's structural connectome: A quantitative stroke lesion-dysfunction mapping study.

    PubMed

    Kuceyeski, Amy; Navi, Babak B; Kamel, Hooman; Relkin, Norman; Villanueva, Mark; Raj, Ashish; Toglia, Joan; O'Dell, Michael; Iadecola, Costantino

    2015-06-01

    The aim of this work was to quantitatively model cross-sectional relationships between structural connectome disruptions caused by cerebral infarction and measures of clinical performance. Imaging biomarkers of 41 ischemic stroke patients (72.0 ± 12.0 years, 20 female) were related to their baseline performance in 18 cognitive, physical and daily life activity assessments. Individual estimates of structural connectivity disruption in gray matter regions were computed using the Change in Connectivity (ChaCo) score. ChaCo scores were utilized because they can be calculated using routinely collected clinical magnetic resonance imagings. Partial Least Squares Regression (PLSR) was used to predict various acute impairment and activity measures from ChaCo scores and patient demographics. Statistical methods of cross-validation, bootstrapping and multiple comparisons correction were implemented to minimize over-fitting and Type I errors. Multiple linear regression models based on lesion volume and lateralization information were constructed for comparison. All models based on connectivity disruption had lower Akaike Information Criterion and almost all had better goodness-of-fit values (R(2) : 0.26-0.92) than models based on lesion characteristics (R(2) : 0.06-0.50). Confidence intervals of PLSR coefficients identified brain regions important in predicting each clinical assessment. Appropriate mapping of eloquent functions, that is, language and motor, and replication of results across pathologies provided validation of this method. Models of complex functions provided new insights into brain-behavior relationships. In addition to the potential applications in prognostication and rehabilitation development, this quantitative approach provides insight into the structural networks underlying complex functions like activities of daily living and cognition. Quantitative analysis of big data will be invaluable in understanding complex brain-behavior relationships. PMID

  2. Exploring the brain's structural connectome: a quantitative stroke lesion-dysfunction mapping study

    PubMed Central

    Kuceyeski, Amy; Navi, Babak B.; Kamel, Hooman; Relkin, Norman; Villanueva, Mark; Raj, Ashish; Toglia, Joan; O'Dell, Michael; Iadecola, Costantino

    2015-01-01

    The aim of this work was to quantitatively model cross-sectional relationships between structural connectome disruptions caused by cerebral infarction and measures of clinical performance. Imaging biomarkers of 41 ischemic stroke patients (72.0±12.0 years, 20 female) were related to their baseline performance in 18 cognitive, physical and daily life activity assessments. Individual estimates of structural connectivity disruption in gray matter regions were computed using the Change in Connectivity (ChaCo) score. ChaCo scores were utilized because they can be calculated using routinely collected clinical MRIs. Partial Least Squares Regression (PLSR) was used to predict various acute impairment and activity measures from ChaCo scores and patient demographics. Statistical methods of cross-validation, bootstrapping and multiple comparisons correction were implemented to minimize over-fitting and Type I errors. Multiple linear regression models based on lesion volume and lateralization information were constructed for comparison. All models based on connectivity disruption had lower Akaike Information Criterion and almost all had better goodness-of-fit values (R2:0.26-0.92) than models based on lesion characteristics (R2:0.06-0.50). Confidence intervals of PLSR coefficients identified brain regions important in predicting each clinical assessment. Appropriate mapping of eloquent functions, i.e. language and motor, and replication of results across pathologies provided validation of this method. Models of complex functions provided new insights into brain-behavior relationships. In addition to the potential applications in prognostication and rehabilitation development, this quantitative approach provides insight into the structural networks underlying complex functions like activities of daily living and cognition. Quantitative analysis of big data will be invaluable in understanding complex brain-behavior relationships. PMID:25655204

  3. A quantitative evaluation study of four-dimensional gated cardiac SPECT reconstruction.

    PubMed

    Jin, Mingwu; Yang, Yongyi; Niu, Xiaofeng; Marin, Thibault; Brankov, Jovan G; Feng, Bing; Pretorius, P Hendrik; King, Michael A; Wernick, Miles N

    2009-09-21

    In practice, gated cardiac SPECT images suffer from a number of degrading factors, including distance-dependent blur, attenuation, scatter and increased noise due to gating. Recently, we proposed a motion-compensated approach for four-dimensional (4D) reconstruction for gated cardiac SPECT and demonstrated that use of motion-compensated temporal smoothing could be effective for suppressing the increased noise due to lowered counts in individual gates. In this work, we further develop this motion-compensated 4D approach by also taking into account attenuation and scatter in the reconstruction process, which are two major degrading factors in SPECT data. In our experiments, we conducted a thorough quantitative evaluation of the proposed 4D method using Monte Carlo simulated SPECT imaging based on the 4D NURBS-based cardiac-torso (NCAT) phantom. In particular, we evaluated the accuracy of the reconstructed left ventricular myocardium using a number of quantitative measures including regional bias-variance analyses and wall intensity uniformity. The quantitative results demonstrate that use of motion-compensated 4D reconstruction can improve the accuracy of the reconstructed myocardium, which in turn can improve the detectability of perfusion defects. Moreover, our results reveal that while traditional spatial smoothing could be beneficial, its merit would become diminished with the use of motion-compensated temporal regularization. As a preliminary demonstration, we also tested our 4D approach on patient data. The reconstructed images from both simulated and patient data demonstrated that our 4D method can improve the definition of the LV wall. PMID:19724094

  4. Quantitative 3D breast magnetic resonance imaging fibroglandular tissue analysis and correlation with qualitative assessments: a feasibility study

    PubMed Central

    Mema, Eralda; Guo, Xiaotao; Mango, Victoria; Desperito, Elise; Ha, Jason; Wynn, Ralph; Zhao, Binsheng

    2016-01-01

    Background The amount of fibroglandular tissue (FGT) has been linked to breast cancer risk based on mammographic density studies. Currently, the qualitative assessment of FGT on mammogram (MG) and magnetic resonance imaging (MRI) is prone to intra and inter-observer variability. The purpose of this study is to develop an objective quantitative FGT measurement tool for breast MRI that could provide significant clinical value. Methods An IRB approved study was performed. Sixty breast MRI cases with qualitative assessment of mammographic breast density and MRI FGT were randomly selected for quantitative analysis from routine breast MRIs performed at our institution from 1/2013 to 12/2014. Blinded to the qualitative data, whole breast and FGT contours were delineated on T1-weighted pre contrast sagittal images using an in-house, proprietary segmentation algorithm which combines the region-based active contours and a level set approach. FGT (%) was calculated by: [segmented volume of FGT (mm3)/(segmented volume of whole breast (mm3)] ×100. Statistical correlation analysis was performed between quantified FGT (%) on MRI and qualitative assessments of mammographic breast density and MRI FGT. Results There was a significant positive correlation between quantitative MRI FGT assessment and qualitative MRI FGT (r=0.809, n=60, P<0.001) and mammographic density assessment (r=0.805, n=60, P<0.001). There was a significant correlation between qualitative MRI FGT assessment and mammographic density assessment (r=0.725, n=60, P<0.001). The four qualitative assessment categories of FGT correlated with the calculated mean quantitative FGT (%) of 4.61% (95% CI, 0–12.3%), 8.74% (7.3–10.2%), 18.1% (15.1–21.1%), 37.4% (29.5–45.3%). Conclusions Quantitative measures of FGT (%) were computed with data derived from breast MRI and correlated significantly with conventional qualitative assessments. This quantitative technique may prove to be a valuable tool in clinical use by

  5. Diffraction enhance x-ray imaging for quantitative phase contrast studies

    NASA Astrophysics Data System (ADS)

    Agrawal, A. K.; Singh, B.; Kashyap, Y. S.; Shukla, Mayank; Sarkar, P. S.; Sinha, Amar

    2016-05-01

    Conventional X-ray imaging based on absorption contrast permits limited visibility of feature having small density and thickness variations. For imaging of weakly absorbing material or materials possessing similar densities, a novel phase contrast imaging techniques called diffraction enhanced imaging has been designed and developed at imaging beamline Indus-2 RRCAT Indore. The technique provides improved visibility of the interfaces and show high contrast in the image forsmall density or thickness gradients in the bulk. This paper presents basic principle, instrumentation and analysis methods for this technique. Initial results of quantitative phase retrieval carried out on various samples have also been presented.

  6. Quantitative absorption and fluorescence studies of NO between 1060 and 2000 A

    NASA Technical Reports Server (NTRS)

    Guest, J. A.; Lee, L. C.

    1981-01-01

    Synchrotron radiation in the 1060 to 2000 A region was used to measure the average absorption and fluorescence cross sections of NO and to determine approximate photodissociation quantum yields. Several vibrational levels of the D(2) sigma(+), E(2) sigma(+), and B(2) delta states have high fluorescence quantum yields. The C(2) and B(2) states do not fluoresce when the excitation energies are above the first dissociation limit, in accord with previous experiments. In general, the fluorescence yields decrease with increasing photon energy. The quantitative measurements are compared with spectroscopic observations and are found to be reasonably consistent.

  7. The telencephalon of Ichthyophis paucisulcus (Amphibia, Gymnophiona (= Caecilia)). A quantitative cytoarchitectonic study.

    PubMed

    Zilles, K; Welsch, U; Schleicher, A

    1981-01-01

    A parcellation of the telencephalon of Ichthyophis paucisulcus (Amphibia, Gymnophiona (= Caecilia) has been performed with a quantitative cytoarchitectonic method. Ten different regions have been delineated and compared with earlier reports on telencephalic regions in anurans, urodeles and caecilians. The most striking difference between the brain of Ichthyophis and other amphibian brains is the high level of morphological differentiation of the accessory olfactory bulb in Ichthyophis and the large extension of this brain region. This feature may be a correlate of the advanced development and the particular structure of Jacobson's organ in this species. PMID:7336818

  8. Development, validation and quantitative assessment of an enzymatic assay suitable for small molecule screening and profiling: A case-study

    PubMed Central

    Sancenon, Vicente; Goh, Wei Hau; Sundaram, Aishwarya; Er, Kai Shih; Johal, Nidhi; Mukhina, Svetlana; Carr, Grant; Dhakshinamoorthy, Saravanakumar

    2015-01-01

    The successful discovery and subsequent development of small molecule inhibitors of drug targets relies on the establishment of robust, cost-effective, quantitative, and physiologically relevant in vitro assays that can support prolonged screening and optimization campaigns. The current study illustrates the process of developing and validating an enzymatic assay for the discovery of small molecule inhibitors using alkaline phosphatase from bovine intestine as model target. The assay development workflow includes an initial phase of optimization of assay materials, reagents, and conditions, continues with a process of miniaturization and automation, and concludes with validation by quantitative measurement of assay performance and signal variability. The assay is further evaluated for dose–response and mechanism-of-action studies required to support structure–activity-relationship studies. Emphasis is placed on the most critical aspects of assay optimization and other relevant considerations, including the technology, assay materials, buffer constituents, reaction conditions, liquid handling equipment, analytical instrumentation, and quantitative assessments. Examples of bottlenecks encountered during assay development and strategies to address them are provided. PMID:27077032

  9. [Quantitative ultrasound].

    PubMed

    Barkmann, R; Glüer, C-C

    2006-10-01

    Methods of quantitative ultrasound (QUS) can be used to obtain knowledge about bone fragility. Comprehensive study results exist showing the power of QUS for the estimation of osteoporotic fracture risk. Nevertheless, the variety of technologies, devices, and variables as well as different degrees of validation of the single devices have to be taken into account. Using methods to simulate ultrasound propagation, the complex interaction between ultrasound and bone could be understood and the propagation could be visualized. Preceding widespread clinical use, it has to be clarified if patients with low QUS values will profit from therapy, as it has been shown for DXA. Moreover, the introduction of quality assurance measures is essential. The user should know the limitations of the methods and be able to interpret the results correctly. Applied in an adequate manner QUS methods could then, due to lower costs and absence of ionizing radiation, become important players in osteoporosis management. PMID:16896637

  10. Normative data for multisite quantitative ultrasound: the Canadian Multicenter Osteoporosis Study.

    PubMed

    Olszynski, Wojciech P; Brown, Jacques P; Adachi, Jonathan D; Hanley, David A; Ioannidis, George; Davison, K Shawn

    2014-01-01

    Multisite quantitative ultrasound (mQUS) machines are attractive tools for assessing fragility fracture risk as they are often portable, comparatively inexpensive, require little training for their use, and emit no ionizing radiation. The primary objective of this investigation was to generate an mQUS normative database of speed of sound (SOS, in m/s) measures from a large sample of randomly selected community-based individuals. mQUS (BeamMed Omnisense MultiSite Quantitative Ultrasound 7000 S) measurements were obtained and assessed at the distal radius, tibia, and phalanx. All analyses were made separately for men and women and for each anatomical site. Scatterplots (SOS vs age) identified 30-39 yr of age as periods of both maximal SOS and of relative stability for all 3 sites over the age span investigated (30-96 yr of age; 2948 women and 1176 men) and, thus, was used as the "reference" population. For cross-sectional comparison of trends over aging, a number of age groupings were created: 30-39, 40-49, 50-59, 60-69, 70-79, and 80+ yr. In general, there were decreases in SOS over increasing age groupings. The normative data generated can be used to compare a given patient's mQUS measurement with reference to a young, healthy population, assigning them a gender-appropriate T-score. PMID:24169082

  11. A Quantitative Microfluidic Angiogenesis Screen for Studying Anti-Angiogenic Therapeutic Assay

    PubMed Central

    Kim, Choong; Kasuya, Junichi; Jeon, Jessie; Chung, Seok; Kamm, Roger D.

    2015-01-01

    Anti-angiogenic therapy, which suppresses tumor growth by disrupting oxygen and nutrient supply from blood to the tumor, is now widely accepted as a treatment for cancer. To investigate the mechanisms of action of these anti-angiogenesis drugs, new three dimensional (3D) cell culture-based drug screening models are increasingly employed. However, there is no in vitro high-throughput screening (HTS) angiogenesis assay that can provide uniform culture conditions for quantitative assessment of physiological responses to chemoattractant reagents under various concentrations of anti-angiogenesis drugs. Here we describe a method for screening and quantifying the vascular endothelial growth factor (VEGF)-induced chemotactic response on human umbilical vein endothelial cells (HUVECs) cultured under different concentrations of bortezomib, a selective 26S proteasome inhibitor. With this quantitative microfluidic angiogenesis screen (QMAS), we demonstrate that bortezomib-induced endothelial cell death was preceded by a series of morphological changes that develop over several days. We also explore the mechanisms by which bortezomib can inhibit angiogenesis. PMID:25370780

  12. Effects of ball-milling and cryomilling on sulfamerazine polymorphs: a quantitative study.

    PubMed

    Macfhionnghaile, Pól; Hu, Yun; Gniado, Katarzyna; Curran, Sinead; Mcardle, Patrick; Erxleben, Andrea

    2014-06-01

    The effects of ball-milling and cryomilling on sulfamerazine forms I and II (SMZ FI, FII) were investigated using X-ray powder diffraction, infrared and near-infrared (NIR) spectroscopy. Cryomilling resulted in a complete amorphization of both polymorphs. Milling at room temperature gave mixtures of amorphous SMZ (FA) and FII. Calibration models were developed for the quantitative analysis of binary (FI/FII, FI/FA, and FII/FA) and ternary (FI/FII/FA) mixtures using NIR spectroscopy combined with partial least-squares (PLS) regression. The PLS models for binary (0%-100%), ternary (0%-100%), and low-level (0%-10%) binary mixtures had root-mean-square errors of prediction of ≤1.8%, ≤5.1%, and ≤0.80%, respectively. The calibration models were used to obtain a detailed quantitative picture of solid-state transformations during milling and any subsequent recrystallizations. FA prepared by cryomilling FI for less than 60 min recrystallized to mixtures of FI and FII, whereas samples milled for more than 60 min crystallized to pure FII. The effect of comilling SMZ with stoichiometric amounts of additives was investigated. SMZ formed amorphous materials with oxalic, dl-tartaric, and citric acids that were more stable toward recrystallization than FA. Amorphous SMZ/oxalic acid was found to recrystallize to a 2:1 cocrystal during storage. PMID:24756899

  13. A quantitative microfluidic angiogenesis screen for studying anti-angiogenic therapeutic drugs.

    PubMed

    Kim, Choong; Kasuya, Junichi; Jeon, Jessie; Chung, Seok; Kamm, Roger D

    2015-01-01

    Anti-angiogenic therapy, which suppresses tumor growth by disrupting oxygen and nutrient supply from blood to the tumor, is now widely accepted as a treatment for cancer. To investigate the mechanisms of action of these anti-angiogenesis drugs, new three dimensional (3D) cell culture-based drug screening models are increasingly employed. However, there is no in vitro high-throughput screening (HTS) angiogenesis assay that can provide uniform culture conditions for the quantitative assessment of physiological responses to chemoattractant reagents under various concentrations of anti-angiogenesis drugs. Here we describe a method for screening and quantifying the vascular endothelial growth factor (VEGF)-induced chemotactic response on human umbilical vein endothelial cells (HUVECs) cultured with different concentrations of bortezomib, a selective 26S proteasome inhibitor. With this quantitative microfluidic angiogenesis screen (QMAS), we demonstrate that bortezomib-induced endothelial cell death is preceded by a series of morphological changes that develop over several days. We also explore the mechanisms by which bortezomib can inhibit angiogenesis. PMID:25370780

  14. The fate of (125I)iodoepidermal growth factor in isolated hepatocytes: a quantitative electron microscopic autoradiographic study

    SciTech Connect

    Carpentier, J.L.; Gorden, P.; Freychet, P.; Canivet, B.; Orci, L.

    1981-09-01

    When (125I)iodoepidermal growth factor is incubated with freshly isolated rat hepatocytes, cell-associated radioactivity reaches apparent steady state by 60 min at 20 C and by 30 min of incubation at 37 C. When the distribution of cell-associated radioactivity is studied at different times of incubation by quantitative electron microscopic autoradiography, the ligand initially associates with the plasma membrane and is progressively internalized as a function of time. The internalized ligand preferentially associates with lysosome-like structures. Qualitatively, these events are similar to those previously obtained with labeled insulin and glucagon in this cell, but quantitatively, the internalization of epidermal growth factor is much greater. The data suggest that the ligand or its specific receptor rather than the cell type is the major determinant of the rate of internalization.

  15. Validation of reference genes for real-time quantitative PCR studies in gene expression levels of Lactobacillus casei Zhang.

    PubMed

    Zhao, Wenjing; Li, Yan; Gao, Pengfei; Sun, Zhihong; Sun, Tiansong; Zhang, Heping

    2011-09-01

    Lactobacillus casei Zhang, a potential probiotic strain isolated from homemade koumiss in Inner Mongolia of China, has been sequenced and deposited in GenBank. Real-time quantitative PCR is one of the most widely used methods to study related gene expression levels of Lactobacillus casei Zhang. For accurate and reliable gene expression analysis, normalization of gene expression data using one or more appropriate reference genes is essential. We used three statistical methods (geNorm, NormFinder, and BestKeeper) to evaluate the expression levels of five candidate reference genes (GAPD, gyrB, LDH, 16s rRNA, and recA) under different culture conditions and different growth phases to find a suitable housekeeping gene which can be used as internal standard. The results showed that the best reference gene was GAPD, and a set of two genes, GAPD and gyrB (which were the most stable reference genes), is recommended for normalization of real-time quantitative PCR experiments under all the different experimental conditions tested. The systematic validation of candidate reference genes is important for obtaining reliable analysis results of real-time quantitative PCR studies in gene expression levels of Lactobacillus casei Zhang. PMID:21104423

  16. Gas chromatography-olfactometry and chemical quantitative study of the aroma of six premium quality spanish aged red wines.

    PubMed

    Culleré, Laura; Escudero, Ana; Cacho, Juan; Ferreira, Vicente

    2004-03-24

    The aroma of six premium quality Spanish red wines has been studied by quantitative gas chromatography-olfactometry (GC-O) and techniques of quantitative chemical analysis. The GC-O study revealed the presence of 85 aromatic notes in which 78 odorants were identified, two of which-1-nonen-3-one (temptatively) and 2-acetylpyrazine-are reported in wine for the first time. Forty out of the 82 quantified odorants may be present at concentrations above their odor threshold. The components with the greatest capacity to introduce differences between these wines are ethyl phenols produced by Brettanomyces yeasts (4-ethylphenol, 4-ethyl-2-methoxyphenol, and 4-propyl-2-methoxyphenol), 2,5-dimethyl-4-hydroxy-3(2H)-furanone (furaneol), (Z)-3-hexenol, thiols derived from cysteinic precursors (4-methyl-4-mercaptopentan-2-one, 3-mercaptohexyl acetate, and 3-mercaptohexanol), some components yielded by the wood [(E)-isoeugenol, 4-allyl-2-methoxyphenol, vanillin, 2-methoxyphenol (guaiacol), and (Z)-whiskylactone], and compounds related to the metabolism (2-phenylethanol, ethyl esters of isoacids, 3-methylbutyl acetate) or oxidative degradation of amino acids [phenylacetaldehyde and 4,5-dimethyl-3-hydroxy-2(5H)-furanone (sotolon)]. The correlation between the olfactometric intensities and the quantitative data is, in general, satisfactory if olfactometric differences between the samples are high. However, GC-O fails in detecting quantitative differences in those cases in which the olfactive intensity is very high or if odors elute in areas in which the odor chromatogram is too complex. PMID:15030226

  17. Quantitative crystalline silica exposure assessment for a historical cohort epidemiologic study in the German porcelain industry.

    PubMed

    Birk, Thomas; Guldner, Karlheinz; Mundt, Kenneth A; Dahmann, Dirk; Adams, Robert C; Parsons, William

    2010-09-01

    A time-dependent quantitative exposure assessment of silica exposure among nearly 18,000 German porcelain workers was conducted. Results will be used to evaluate exposure-response disease risks. Over 8000 historical industrial hygiene (IH) measurements with original sampling and analysis protocols from 1954-2006 were obtained from the German Berufs- genossenschaft der keramischen-und Glas-Industrie (BGGK) and used to construct a job exposure matrix (JEM). Early measurements from different devices were converted to modern gravimetric equivalent values. Conversion factors were derived from parallel historical measurements and new side-by-side measurements using historical and modern devices in laboratory dust tunnels and active workplace locations. Exposure values were summarized and smoothed using LOESS regression; estimates for early years were derived using backward extrapolation techniques. Employee work histories were merged with JEM values to determine cumulative crystalline silica exposures for cohort members. Average silica concentrations were derived for six primary similar exposure groups (SEGs) for 1938-2006. Over 40% of the cohort accumulated <0.5 mg; just over one-third accumulated >1 mg/m(3)-years. Nearly 5000 workers had cumulative crystalline silica estimates >1.5 mg/m(3)-years. Similar numbers of men and women fell into each cumulative exposure category, except for 1113 women and 1567 men in the highest category. Over half of those hired before 1960 accumulated >3 mg/m(3)-years crystalline silica compared with 4.9% of those hired after 1960. Among those ever working in the materials preparation area, half accumulated >3 mg/m(3)-year compared with 12% of those never working in this area. Quantitative respirable silica exposures were estimated for each member of this cohort, including employment periods for which sampling used now obsolete technologies. Although individual cumulative exposure estimates ranged from background to about 40 mg/m(3)-years

  18. Bibliometric Analysis of the Korean Journal of Parasitology: Measured from SCI, PubMed, Scopus, and Synapse Databases

    PubMed Central

    2009-01-01

    The Korean Journal of Parasitology (KJP) is the official journal of the Korean Society for Parasitology which is celebrating its 50th anniversary in 2009. To assess the contributions and achievements of the KJP, bibliometric analysis was conducted based on the citation data retrieved from 4 major databases; SCI, PubMed, Synapse, and Scopus. It was found that the KJP articles were constantly cited by the articles published in major international journals represented in these databases. More than 60% of 1,370 articles published in the KJP from 1963 to June 2009 were cited at least once by SCI articles. The overall average times cited by SCI articles are 2.6. The rate is almost 3 times higher for the articles published in the last 10 years compared to 1.0 for the articles of the 1960s. The SCI journal impact factor for 2008 is calculated as 0.871. It is increasing and it is expected to increase further with the introduction of the KJP in the database in 2008. The more realistic h-indixes were measured from the study data set covering all the citations to the KJP; 17 for SCI, 6 for PubMed, 19 for Synapse, and 17 for Scopus. Synapse extensively picked up the citations to the earlier papers not retrievable from the other 3 databases. It identified many papers published in the 1960s and in the 1980s which have been cited heavily, proving the central role of the KJP in the dissemination of the important research findings over the last 5 decades. PMID:19885331

  19. [Studies of biologic activation associated with molecular receptor increase and tumor response in ChL6/L6 protocol patients; Studies in phantoms; Quantitative SPECT; Preclinical studies; and Clinical studies]. DOE annual report, 1994--95

    SciTech Connect

    DeNardo, S.J.

    1995-12-31

    The authors describe results which have not yet been published from their associated studies listed in the title. For the first, they discuss Lym-1 single chain genetically engineered molecules, analysis of molecular genetic coded messages to enhance tumor response, and human dosimetry and therapeutic human use radiopharmaceuticals. Studies in phantoms includes a discussion of planar image quantitation, counts coincidence correction, organ studies, tumor studies, and {sup 90}Y quantitation with Bremsstrahlung imaging. The study on SPECT discusses attenuation correction and scatter correction. Preclinical studies investigated uptake of {sup 90}Y-BrE-3 in mice using autoradiography. Clinical studies discuss image quantitation verses counts from biopsy samples, S factors for radiation dose calculation, {sup 67}Cu imaging studies for lymphoma cancer, and {sup 111}In MoAb imaging studies for breast cancer to predict {sup 90}Y MoAb therapy.

  20. Electron paramagnetic resonance as a quantitative tool for the study of multiwalled carbon nanotubes

    NASA Astrophysics Data System (ADS)

    Coleman, J. N.; O'Brien, D. F.; Dalton, A. B.; McCarthy, B.; Lahr, B.; Barklie, R. C.; Blau, W. J.

    2000-12-01

    We have described a method that maximizes the phase separation of graphitic particles (GP) and multiwalled carbon nanotubes (MWNT) in solutions of various organic polymeric hosts. This involves the formation of sediment and a solute. These components were characterized for MWNT and GP content using electron paramagnetic resonance (EPR) measurements. All EPR signals could be deconvoluted into nanotube and GP components. When normalized, these components are representative of the mass of MWNT and GP present. This allows us to make quantitative measurements of nanotube and GP content in different environments. The most successful polymer host was poly (m-phenylenevinylene-co-2,5-dioctyloxy-p-phenylenevinylene) (PmPV). In this case the solute contained 63% of the added nanotubes with only 2% of the added graphite remaining.