WorldWideScience

Sample records for gelation electronic resource

  1. Positionally isomeric organic gelators: structure-gelation study, racemic versus enantiomeric gelators, and solvation effects.

    Science.gov (United States)

    Caplar, Vesna; Frkanec, Leo; Sijaković Vujicić, Natasa; Zinić, Mladen

    2010-03-08

    Low molecular weight gelator molecules consisting of aliphatic acid, amino acid (phenylglycine), and omega-aminoaliphatic acid units have been designed. By varying the number of methylene units in the aliphatic and omega-aminoaliphatic acid chains, as defined by descriptors m and n, respectively, a series of positionally isomeric gelators having different positions of the peptidic hydrogen-bonding unit within the gelator molecule has been obtained. The gelation properties of the positional isomers have been determined in relation to a defined set of twenty solvents of different structure and polarity and analyzed in terms of gelator versatility (G(ver)) and effectiveness (G(eff)). The results of gelation tests have shown that simple synthetic optimizations of a "lead gelator molecule" by variation of m and n, end-group polarity (carboxylic acid versus sodium carboxylate), and stereochemistry (racemate versus optically pure form) allowed the identification of gelators with tremendously improved versatility (G(ver)) and effectiveness (G(eff)). Dramatic differences in G(eff) values of up to 70 times could be observed between pure racemate/enantiomer pairs of some gelators, which were manifested even in the gelation of very similar solvents such as isomeric xylenes. The combined results of spectroscopic ((1)H NMR, FTIR), electron microscopy (TEM), and X-ray diffraction studies suggest similar organization of the positionally isomeric gelators at the molecular level, comprising parallel beta-sheet hydrogen-bonded primary assemblies that form inversed bilayers at a higher organizational level. Differential scanning calorimetry (DSC) studies of selected enantiomer/racemate gelator pairs and their o- and p-xylene gels revealed the simultaneous presence of different polymorphs in the racemate gels. The increased gelation effectiveness of the racemate compared to that of the single enantiomer is most likely a consequence of its spontaneous resolution into enantiomeric

  2. Electronic Resource Management Systems

    Directory of Open Access Journals (Sweden)

    Mark Ellingsen

    2004-10-01

    Full Text Available Computer applications which deal with electronic resource management (ERM are quite a recent development. They have grown out of the need to manage the burgeoning number of electronic resources particularly electronic journals. Typically, in the early years of e-journal acquisition, library staff provided an easy means of accessing these journals by providing an alphabetical list on a web page. Some went as far as categorising the e-journals by subject and then grouping the journals either on a single web page or by using multiple pages. It didn't take long before it was recognised that it would be more efficient to dynamically generate the pages from a database rather than to continually edit the pages manually. Of course, once the descriptive metadata for an electronic journal was held within a database the next logical step was to provide administrative forms whereby that metadata could be manipulated. This in turn led to demands for incorporating more information and more functionality into the developing application.

  3. Electronic Resource Management and Design

    Science.gov (United States)

    Abrams, Kimberly R.

    2015-01-01

    We have now reached a tipping point at which electronic resources comprise more than half of academic library budgets. Because of the increasing work associated with the ever-increasing number of e-resources, there is a trend to distribute work throughout the library even in the presence of an electronic resources department. In 2013, the author…

  4. Cold gelation of globular proteins

    NARCIS (Netherlands)

    Alting, A.C.

    2003-01-01

    Keywords : globular proteins, whey protein, ovalbumin, cold gelation, disulfide bonds, texture, gel hardnessProtein gelation in food products is important to obtain desirable sensory and textural properties. Cold gelation is a novel method to produce protein-based gels. It is a two step process in

  5. Managing electronic resources a LITA guide

    CERN Document Server

    Weir, Ryan O

    2012-01-01

    Informative, useful, current, Managing Electronic Resources: A LITA Guide shows how to successfully manage time, resources, and relationships with vendors and staff to ensure personal, professional, and institutional success.

  6. Electronic Resources Management Project Presentation 2012

    KAUST Repository

    Ramli, Rindra M.

    2012-11-05

    This presentation describes the electronic resources management project undertaken by the KAUST library. The objectives of this project is to migrate information from MS Sharepoint to Millennium ERM module. One of the advantages of this migration is to consolidate all electronic resources into a single and centralized location. This would allow for better information sharing among library staff.

  7. Implementing CORAL: An Electronic Resource Management System

    Science.gov (United States)

    Whitfield, Sharon

    2011-01-01

    A 2010 electronic resource management survey conducted by Maria Collins of North Carolina State University and Jill E. Grogg of University of Alabama Libraries found that the top six electronic resources management priorities included workflow management, communications management, license management, statistics management, administrative…

  8. Fine-Tuning of Saponification-Triggered Gelation by Strategic Modification of Peripheral Substituents: Gelation Regulators.

    Science.gov (United States)

    Kumar, Ashish; Singh, Roop Shikha; Kumar, Amit; Ali, Afsar; Biswas, Arnab; Pandey, Daya Shankar

    2016-09-19

    A pioneering approach towards controlling the efficiency of saponification assisted gelation in ethyl ester based Zn II -complexes have been described. Using four new ester containing bis-salen Zn II complexes (C1-C4) involving different para-azo phenyl substituted ligands it has been clearly shown that gelation efficiency is greatly influenced by the electronic effects of the substituents (-H (C1), -CH 3 (C2), -NO 2 (C3), and -OCH 3 (C4)). Morphological, photophysical, and rheological investigations corroborated the experimental observations well and established that gelation efficiency was enhanced with electron-withdrawing characteristics of substituents (C4

  9. Electronic Resources Management System: Recommendation Report 2017

    KAUST Repository

    Ramli, Rindra M.

    2017-01-01

    This recommendation report provides an overview of the selection process for the new Electronic Resources Management System. The library has decided to move away from Innovative Interfaces Millennium ERM module. The library reviewed 3 system

  10. Electronic Resources Management Project Presentation 2012

    KAUST Repository

    Ramli, Rindra M.

    2012-01-01

    This presentation describes the electronic resources management project undertaken by the KAUST library. The objectives of this project is to migrate information from MS Sharepoint to Millennium ERM module. One of the advantages of this migration

  11. PRINCIPLES OF CONTENT FORMATION EDUCATIONAL ELECTRONIC RESOURCE

    Directory of Open Access Journals (Sweden)

    О Ю Заславская

    2017-12-01

    Full Text Available The article considers modern possibilities of information and communication technologies for the design of electronic educational resources. The conceptual basis of the open educational multimedia system is based on the modular architecture of the electronic educational resource. The content of the electronic training module can be implemented in several versions of the modules: obtaining information, practical exercises, control. The regularities in the teaching process in modern pedagogical theory are considered: general and specific, and the principles for the formation of the content of instruction at different levels are defined, based on the formulated regularities. On the basis of the analysis, the principles of the formation of the electronic educational resource are determined, taking into account the general and didactic patterns of teaching.As principles of the formation of educational material for obtaining information for the electronic educational resource, the article considers: the principle of methodological orientation, the principle of general scientific orientation, the principle of systemic nature, the principle of fundamentalization, the principle of accounting intersubject communications, the principle of minimization. The principles of the formation of the electronic training module of practical studies in the article include: the principle of systematic and dose based consistency, the principle of rational use of study time, the principle of accessibility. The principles of the formation of the module for monitoring the electronic educational resource can be: the principle of the operationalization of goals, the principle of unified identification diagnosis.

  12. Electronic Resources Management System: Recommendation Report 2017

    KAUST Repository

    Ramli, Rindra M.

    2017-05-01

    This recommendation report provides an overview of the selection process for the new Electronic Resources Management System. The library has decided to move away from Innovative Interfaces Millennium ERM module. The library reviewed 3 system as potential replacements namely: Proquest 360 Resource Manager, Ex Libris Alma and Open Source CORAL ERMS. After comparing and trialling the systems, it was decided to go for Proquest 360 Resource Manager.

  13. CHALLENGES OF ELECTRONIC INFORMATION RESOURCES IN ...

    African Journals Online (AJOL)

    This paper discusses the role of policy for proper and efficient library services in the electronic era. It points out some of the possible dangers of embarking in electronic resources without a proper focus at hand. Thus, it calls for today's librarians and policy makers to brainstorm and come up with working policies suitable to ...

  14. Gelation under shear

    Energy Technology Data Exchange (ETDEWEB)

    Butler, B.D.; Hanley, H.J.M.; Straty, G.C. [National Institute of Standards and Technology, Boulder, CO (United States); Muzny, C.D. [Univ. of Colorado, Boulder, CO (United States)

    1995-12-31

    An experimental small angle neutron scattering (SANS) study of dense silica gels, prepared from suspensions of 24 nm colloidal silica particles at several volume fractions {theta} is discussed. Provided that {theta}{approx_lt}0.18, the scattered intensity at small wave vectors q increases as the gelation proceeds, and the structure factor S(q, t {yields} {infinity}) of the gel exhibits apparent power law behavior. Power law behavior is also observed, even for samples with {theta}>0.18, when the gel is formed under an applied shear. Shear also enhances the diffraction maximum corresponding to the inter-particle contact distance of the gel. Difficulties encountered when trying to interpret SANS data from these dense systems are outlined. Results of computer simulations intended to mimic gel formation, including computations of S(q, t), are discussed. Comments on a method to extract a fractal dimension characterizing the gel are included.

  15. Library training to promote electronic resource usage

    DEFF Research Database (Denmark)

    Frandsen, Tove Faber; Tibyampansha, Dativa; Ibrahim, Glory

    2017-01-01

    Purpose: Increasing the usage of electronic resources is an issue of concern for many libraries all over the world. Several studies stress the importance of information literacy and instruction in order to increase the usage. Design/methodology/approach: The present article presents the results...

  16. Electronic resource management systems a workflow approach

    CERN Document Server

    Anderson, Elsa K

    2014-01-01

    To get to the bottom of a successful approach to Electronic Resource Management (ERM), Anderson interviewed staff at 11 institutions about their ERM implementations. Among her conclusions, presented in this issue of Library Technology Reports, is that grasping the intricacies of your workflow-analyzing each step to reveal the gaps and problems-at the beginning is crucial to selecting and implementing an ERM. Whether the system will be used to fill a gap, aggregate critical data, or replace a tedious manual process, the best solution for your library depends on factors such as your current soft

  17. use of electronic resources by graduate students of the department

    African Journals Online (AJOL)

    respondent's access electronic resources from the internet via Cybercafé .There is a high ... KEY WORDS: Use, Electronic Resources, Graduate Students, Cybercafé. INTRODUCTION ... Faculty of Education, University of Uyo, Uyo. Olu Olat ...

  18. Organic Gelators as Growth Control Agents for Stable and Reproducible Hybrid Perovskite-Based Solar Cells

    KAUST Repository

    Masi, Sofia; Rizzo, Aurora; Munir, Rahim; Listorti, Andrea; Giuri, Antonella; Esposito Corcione, Carola; Treat, Neil D.; Gigli, Giuseppe; Amassian, Aram; Stingelin, Natalie; Colella, Silvia

    2017-01-01

    Low-molecular-weight organic gelators are widely used to influence the solidification of polymers, with applications ranging from packaging items, food containers to organic electronic devices, including organic photovoltaics. Here, this concept

  19. Use of Electronic Resources in a Private University in Nigeria ...

    African Journals Online (AJOL)

    The study examined awareness and constraints in the use of electronic resources by lecturers and students of Ajayi Crowther University, Oyo, Nigeria. It aimed at justifying the resources expended in the provision of electronic resources in terms of awareness, patronage and factors that may be affecting awareness and use ...

  20. Gender Analysis Of Electronic Information Resource Use: The Case ...

    African Journals Online (AJOL)

    Based on the findings the study concluded that access and use of electronic information resources creates a “social digital divide” along gender lines. The study ... Finally, the library needs to change its marketing strategies on the availability of electronic information resources to increase awareness of these resources.

  1. Electronic Resource Management System. Vernetzung von Lizenzinformationen

    Directory of Open Access Journals (Sweden)

    Michaela Selbach

    2014-12-01

    Full Text Available In den letzten zehn Jahren spielen elektronische Ressourcen im Bereich der Erwerbung eine zunehmend wichtige Rolle: Eindeutig lässt sich hier ein Wandel in den Bibliotheken (fort vom reinen Printbestand zu immer größeren E-Only-Beständen feststellen. Die stetig wachsende Menge an E-Ressourcen und deren Heterogenität stellt Bibliotheken vor die Herausforderung, die E-Ressourcen effizient zu verwalten. Nicht nur Bibliotheken, sondern auch verhandlungsführende Institutionen von Konsortial- und Allianzlizenzen benötigen ein geeignetes Instrument zur Verwaltung von Lizenzinformationen, welches den komplexen Anforderungen moderner E-Ressourcen gerecht wird. Die Deutsche Forschungsgemeinschaft (DFG unterstützt ein Projekt des Hochschulbibliothekszentrums des Landes Nordrhein-Westfalen (hbz, der Universitätsbibliothek Freiburg, der Verbundzentrale des Gemeinsamen Bibliotheksverbundes (GBV und der Universitätsbibliothek Frankfurt, in dem ein bundesweit verfügbares Electronic Ressource Managementsystem (ERMS aufgebaut werden soll. Ein solches ERMS soll auf Basis einer zentralen Knowledge Base eine einheitliche Nutzung von Daten zur Lizenzverwaltung elektronischer Ressourcen auf lokaler, regionaler und nationaler Ebene ermöglichen. Statistische Auswertungen, Rechteverwaltung für alle angeschlossenen Bibliotheken, kooperative Datenpflege sowie ein über standardisierte Schnittstellen geführter Datenaustausch stehen bei der Erarbeitung der Anforderungen ebenso im Fokus wie die Entwicklung eines Daten- und Funktionsmodells. In the last few years the importance of electronic resources in library acquisitions has increased significantly. There has been a shift from mere print holdings to both e- and print combinations and even e-only subscriptions. This shift poses a double challenge for libraries: On the one hand they have to provide their e-resource collections to library users in an appealing way, on the other hand they have to manage these

  2. Electronic human resource management: Enhancing or entrancing?

    Directory of Open Access Journals (Sweden)

    Paul Poisat

    2017-07-01

    Full Text Available Orientation: This article provides an investigation into the current level of development of the body of knowledge related to electronic human resource management (e-HRM by means of a qualitative content analysis. Several aspects of e-HRM, namely definitions of e-HRM, the theoretical perspectives around e-HRM, the role of e-HRM, the various types of e-HRM and the requirements for successful e-HRM, are examined. Research purpose: The purpose of the article was to determine the status of e-HRM and examine the studies that report on the link between e-HRM and organisational productivity. Motivation for the study: e-HRM has the capacity to improve organisational efficiency and leverage the role of human resources (HR as a strategic business partner. Main findings: The notion that the implementation of e-HRM will lead to improved organisational productivity is commonly assumed; however, empirical evidence in this regard was found to be limited. Practical/managerial implications: From the results of this investigation it is evident that more research is required to gain a greater understanding of the influence of e-HRM on organisational productivity, as well as to develop measures for assessing this influence. Contribution: This article proposes additional areas to research and measure when investigating the effectiveness of e-HRM. It provides a different lens from which to view e-HRM assessment whilst keeping it within recognised HR measurement parameters (the HR value chain. In addition, it not only provides areas for measuring e-HRM’s influence but also provides important clues as to how the measurements may be approached.

  3. Utilization of electronic information resources by academic staff at ...

    African Journals Online (AJOL)

    The study investigated the utilization of Electronic Information resources by the academic staff of Makerere University in Uganda. It examined the academic staff awareness of the resources available, the types of resources provided by the Makerere University Library, the factors affecting resource utilization. The study was ...

  4. Users satisfaction with electronic information resources and services ...

    African Journals Online (AJOL)

    This study investigated users satisfaction on the use of electronic information resources and services in MTN Net libraries in ABU & UNIBEN. Two objectives and one null hypotheses were formulated and tested with respect to the users' satisfaction on electronic information resources and services in MTN Net libraries in ...

  5. The Role of the Acquisitions Librarian in Electronic Resources Management

    Science.gov (United States)

    Pomerantz, Sarah B.

    2010-01-01

    With the ongoing shift to electronic formats for library resources, acquisitions librarians, like the rest of the profession, must adapt to the rapidly changing landscape of electronic resources by keeping up with trends and mastering new skills related to digital publishing, technology, and licensing. The author sought to know what roles…

  6. Selection and Evaluation of Electronic Resources

    Directory of Open Access Journals (Sweden)

    Doğan Atılgan

    2013-11-01

    Full Text Available Publication boom and issues related to controlling and accession of printed sources have created some problems after World War II. Consequently, publishing industry has encountered the problem of finding possible solution for emerged situation. Industry of electronic publishing has started to improve with the rapid increase of the price of printed sources as well as the problem of publication boom. The first effects of electronic publishing were appeared on the academic and scholarly publications then electronic publishing became a crucial part of all types of publications. As a result of these developments, collection developments and service policies of information centers were also significantly changed. In this article, after a general introduction about selection and evaluation processes of electronic publications, the subscribed databases by a state and a privately owned university in Turkey and their usage were examined.

  7. Improving Electronic Resources through Holistic Budgeting

    Science.gov (United States)

    Kusik, James P.; Vargas, Mark A.

    2009-01-01

    To establish a more direct link between its collections and the educational goals of Saint Xavier University, the Byrne Memorial Library has adopted a "holistic" approach to collection development. This article examines how traditional budget practices influenced the library's selection of resources and describes how holistic collection…

  8. Page 170 Use of Electronic Resources by Undergraduates in Two ...

    African Journals Online (AJOL)

    undergraduate students use electronic resources such as NUC virtual library, HINARI, ... web pages articles from magazines, encyclopedias, pamphlets and other .... of Nigerian university libraries have Internet connectivity, some of the system.

  9. Utilisation of Electronic Information Resources By Lecturers in ...

    African Journals Online (AJOL)

    This study assesses the use of information resources, specifically, electronic databases by lecturers/teachers in Universities and Colleges of Education in South Western Nigeria. Information resources are central to teachers' education. It provides lecturers/teachers access to information that enhances research and ...

  10. Preservation and conservation of electronic information resources of ...

    African Journals Online (AJOL)

    The major holdings of the broadcast libraries of the Nigerian Television Authority (NTA) are electronic information resources; therefore, providing safe places for general management of these resources have aroused interest in the industry in Nigeria for sometimes. The need to study the preservation and conservation of ...

  11. Using XML Technologies to Organize Electronic Reference Resources

    OpenAIRE

    Huser, Vojtech; Del Fiol, Guilherme; Rocha, Roberto A.

    2005-01-01

    Provision of access to reference electronic resources to clinicians is becoming increasingly important. We have created a framework for librarians to manage access to these resources at an enterprise level, rather than at the individual hospital libraries. We describe initial project requirements, implementation details, and some preliminary results.

  12. Euler European Libraries and Electronic Resources in Mathematical Sciences

    CERN Document Server

    The Euler Project. Karlsruhe

    The European Libraries and Electronic Resources (EULER) Project in Mathematical Sciences provides the EulerService site for searching out "mathematical resources such as books, pre-prints, web-pages, abstracts, proceedings, serials, technical reports preprints) and NetLab (for Internet resources), this outstanding engine is capable of simple, full, and refined searches. It also offers a browse option, which responds to entries in the author, keyword, and title fields. Further information about the Project is provided at the EULER homepage.

  13. Building an electronic resource collection a practical guide

    CERN Document Server

    Lee, Stuart D

    2004-01-01

    This practical book guides information professionals step-by-step through building and managing an electronic resource collection. It outlines the range of electronic products currently available in abstracting and indexing, bibliographic, and other services and then describes how to effectively select, evaluate and purchase them.

  14. Organizational matters of competition in electronic educational resources

    Directory of Open Access Journals (Sweden)

    Ирина Карловна Войтович

    2015-12-01

    Full Text Available The article examines the experience of the Udmurt State University in conducting competitions of educational publications and electronic resources. The purpose of such competitions is to provide methodological support to educational process. The main focus is on competition of electronic educational resources. The technology of such contests is discussed through detailed analysis of the main stages of the contest. It is noted that the main task of the preparatory stage of the competition is related to the development of regulations on competition and the definition of criteria for selection of the submitted works. The paper also proposes a system of evaluation criteria of electronic educational resources developed by members of the contest organizing committee and jury members. The article emphasizes the importance of not only the preparatory stages of the competition, but also measures for its completion, aimed at training teachers create quality e-learning resources.

  15. Why and How to Measure the Use of Electronic Resources

    Directory of Open Access Journals (Sweden)

    Jean Bernon

    2008-11-01

    Full Text Available A complete overview of library activity implies a complete and reliable measurement of the use of both electronic resources and printed materials. This measurement is based on three sets of definitions: document types, use types and user types. There is a common model of definitions for printed materials, but a lot of questions and technical issues remain for electronic resources. In 2006 a French national working group studied these questions. It relied on the COUNTER standard, but found it insufficient and pointed out the need for local tools such as web markers and deep analysis of proxy logs. Within the French national consortium COUPERIN, a new working group is testing ERMS, SUSHI standards, Shibboleth authentication, along with COUNTER standards, to improve the counting of the electronic resources use. At this stage this counting is insufficient and its improvement will be a European challenge for the future.

  16. Access to electronic resources by visually impaired people

    Directory of Open Access Journals (Sweden)

    Jenny Craven

    2003-01-01

    Full Text Available Research into access to electronic resources by visually impaired people undertaken by the Centre for Research in Library and Information Management has not only explored the accessibility of websites and levels of awareness in providing websites that adhere to design for all principles, but has sought to enhance understanding of information seeking behaviour of blind and visually impaired people when using digital resources.

  17. Practical guide to electronic resources in the humanities

    CERN Document Server

    Dubnjakovic, Ana

    2010-01-01

    From full-text article databases to digitized collections of primary source materials, newly emerging electronic resources have radically impacted how research in the humanities is conducted and discovered. This book, covering high-quality, up-to-date electronic resources for the humanities, is an easy-to-use annotated guide for the librarian, student, and scholar alike. It covers online databases, indexes, archives, and many other critical tools in key humanities disciplines including philosophy, religion, languages and literature, and performing and visual arts. Succinct overviews of key eme

  18. Discipline, availability of electronic resources and the use of Finnish National Electronic Library - FinELib

    Directory of Open Access Journals (Sweden)

    Sanna Torma

    2004-01-01

    Full Text Available This study elaborated relations between digital library use by university faculty, users' discipline and the availability of key resources in the Finnish National Electronic Library (FinELib, Finnish national digital library, by using nationwide representative survey data. The results show that the perceived availability of key electronic resources by researchers in FinELib was a stronger predictor of the frequency and purpose of use of its services than users' discipline. Regardless of discipline a good perceived provision of central resources led to a more frequent use of FinELib. The satisfaction with the services did not vary with the discipline, but with the perceived availability of resources.

  19. Access to electronic information resources by students of federal ...

    African Journals Online (AJOL)

    The paper discusses access to electronic information resources by students of Federal Colleges of Education in Eha-Amufu and Umunze. Descriptive survey design was used to investigate sample of 526 students. Sampling technique used was a Multi sampling technique. Data for the study were generated using ...

  20. Electronic Commerce Resource Centers. An Industry--University Partnership.

    Science.gov (United States)

    Gulledge, Thomas R.; Sommer, Rainer; Tarimcilar, M. Murat

    1999-01-01

    Electronic Commerce Resource Centers focus on transferring emerging technologies to small businesses through university/industry partnerships. Successful implementation hinges on a strategic operating plan, creation of measurable value for customers, investment in customer-targeted training, and measurement of performance outputs. (SK)

  1. ANALYTICAL REVIEW OF ELECTRONIC RESOURCES FOR THE STUDY OF LATIN

    Directory of Open Access Journals (Sweden)

    Olena Yu. Balalaieva

    2014-04-01

    Full Text Available The article investigates the current state of development of e-learning content in the Latin language. It is noted that the introduction of ICT in the educational space has expanded the possibility of studying Latin, opened access to digital libraries resources, made it possible to use scientific and educational potential and teaching Latin best practices of world's leading universities. A review of foreign and Ukrainian information resources and electronic editions for the study of Latin is given. Much attention was paid to the didactic potential of local and online multimedia courses of Latin, electronic textbooks, workbooks of interactive tests and exercises, various dictionaries and software translators, databases and digital libraries. Based on analysis of the world market of educational services and products the main trends in the development of information resources and electronic books are examined. It was found that multimedia courses with interactive exercises or workbooks with interactive tests, online dictionaries and translators are the most widely represented and demanded. The noticeable lagging of Ukrainian education and computer linguistics in quantitative and qualitative measures in this industry is established. The obvious drawback of existing Ukrainian resources and electronic editions for the study of Latin is their noninteractive nature. The prospects of e-learning content in Latin in Ukraine are outlined.

  2. Adoption and use of electronic information resources by medical ...

    African Journals Online (AJOL)

    This study investigated the adoption and use of electronic information resources by medical science students of the University of Benin. The descriptive survey research design was adopted for the study and 390 students provided the data. Data collected were analysed with descriptive Statistics(Simple percentage and ...

  3. Modern ICT Tools: Online Electronic Resources Sharing Using Web ...

    African Journals Online (AJOL)

    Modern ICT Tools: Online Electronic Resources Sharing Using Web 2.0 and Its Implications For Library And Information Practice In Nigeria. ... The PDF file you selected should load here if your Web browser has a PDF reader plug-in installed (for example, a recent version of Adobe Acrobat Reader). If you would like more ...

  4. Technical Communicator: A New Model for the Electronic Resources Librarian?

    Science.gov (United States)

    Hulseberg, Anna

    2016-01-01

    This article explores whether technical communicator is a useful model for electronic resources (ER) librarians. The fields of ER librarianship and technical communication (TC) originated and continue to develop in relation to evolving technologies. A review of the literature reveals four common themes for ER librarianship and TC. While the…

  5. Preparation of curcumin nanoparticle by using reinforcement ionic gelation technique

    Science.gov (United States)

    Suryani, Halid, Nur Hatidjah Awaliyah; Akib, Nur Illiyyin; Rahmanpiu, Mutmainnah, Nina

    2017-05-01

    Curcumin, a polyphenolic compound present in curcuma longa has a wide range of activities including anti-inflammatory properties. The potency of curcumin is limited by its poor oral bioavailability because of its poor solubility in aqueous. Various methods have been tried to solve the problem including its encapsulation into nanoparticle. The aim of this study is to develop curcumin nanoparticle by using reinforcement ionic gelation technique and to evaluate the stability of curcumin nanoparticles in gastrointestinal fluid. Curcumin nanoparticles were prepared by using reinforcement ionic gelation technique with different concentrations of chitosan, trypolyphosphate, natrium alginate and calcium chloride. Curcumin nanoparticles were then characterized including particle size and zeta potential by using particle size analyzer and morphology using a transmission electron microscope, entrapment efficiency using UV-Vis Spectrophotometer and chemical structure analysis by Infra Red Spectrophotometer (FTIR). Furthermore, the stability of curcumin nanoparticles were evaluated on artificial gastric fluid and artificial intestinal fluids by measuring the amount of curcumin released in the medium at a time interval. The result revealed that curcumin nanoparticles can be prepared by reinforcement ionic gelation technique, the entrapment efficiency of curcumin nanoparticles were from 86.08 to 91.41%. The average of particle size was 272.9 nm and zeta potential was 12.05 mV. The morphology examination showed that the curcumin nanoparticles have spherical shape. The stability evaluation of curcumin nanoparticles showed that the nanoparticles were stable on artificial gastric fluid and artificial intestinal fluid. This result indicates that curcumin nanoparticles have the potential to be developed for oral delivery.

  6. Photoinduced gelation by stilbene oxalyl amide compounds.

    Science.gov (United States)

    Miljanić, Snezana; Frkanec, Leo; Meić, Zlatko; Zinić, Mladen

    2005-03-29

    Oxalyl amide derivatives bearing 4-dodecyloxy-stilbene as a cis-trans photoisomerizing unit were synthesized. The trans derivative acted as a versatile gelator of various organic solvents, whereas the corresponding cis derivative showed a poor gelation ability or none at all. In diluted solution (c = 2.0 x10(-5) mol dm(-3), ethanol), the cis isomer was photochemically converted into the trans isomer within 4 min. Depending on the radiation wavelength, the trans isomer was stable or liable to photodecomposition. When exposed to irradiation, a concentrated solution of the cis isomer (c = 2.0 x 10(-2) mol dm(-3), ethanol) turned into a gel. The FT-Raman, FT-IR, and 1H NMR spectra demonstrated that the gelation process occurred because of a rapid cis --> trans photoisomerization followed by a self-assembly of the trans molecules. Apart from the formation of hydrogen bonding between the oxalyl amide parts of the molecules, confirmed by FT-IR spectroscopy, it was assumed that the pi-pi stacking between the trans-stilbene units of the molecule and a lipophilic interaction between long alkyl chains were the interactions responsible for gelation.

  7. Gelation and interfacial behaviour of vegetable proteins

    NARCIS (Netherlands)

    Vliet, T. van; Martin, A.H.; Bos, M.A.

    2002-01-01

    Recent studies on gelation and interfacial properties of vegetable protiens are reviewed. Attention is focused on legume proteins, mainly soy proteins, and on wheat proteins. The rheological properteis of vegetable protein gels as a function of heating time or temperature is discussed as well as the

  8. Gelation and interfacial behaviour of vegetable proteins

    NARCIS (Netherlands)

    Vliet, van T.; Martin, A.H.; Bos, M.A.

    2002-01-01

    Recent studies on gelation and interfacial properties of vegetable proteins are reviewed. Attention is focused on legume proteins, mainly soy proteins, and on wheat proteins. The rheological properties of vegetable protein gels as a function of heating time or temperature is discussed as well as the

  9. Reversible thermal gelation in soft spheres

    DEFF Research Database (Denmark)

    Kapnistos, M.; Vlassopoulos, D.; Fytas, G.

    2000-01-01

    Upon heating, concentrated solutions of star polymers and block copolymer micelles in a good solvent, representing soft spheres, undergo a reversible gelation. This phenomenon is attributed to the formation of clusters causing a partial dynamic arrest of the swollen interpenetrating spheres at hi...

  10. MODEL OF AN ELECTRONIC EDUCATIONAL RESOURCE OF NEW GENERATION

    Directory of Open Access Journals (Sweden)

    Anatoliy V. Loban

    2016-01-01

    Full Text Available The mathematical structure of the modular architecture of an electronic educational resource (EER of new generation, which allows to decompose the process of studying the subjects of the course at a hierarchically ordered set of data (knowledge and procedures for manipulating them, to determine the roles of participants of process of training of and technology the development and use of EOR in the study procrate.

  11. Gelation on heating of supercooled gelatin solutions.

    Science.gov (United States)

    Guigo, Nathanaël; Sbirrazzuoli, Nicolas; Vyazovkin, Sergey

    2012-04-23

    Diluted (1.0-1.5 wt%) aqueous gelatin solutions have been cooled to -10 °C at a cooling rate 20 °C min(-1) without freezing and detectable gelation. When heated at a constant heating rate (0.5 -2 °C min(-1)), the obtained supercooled solutions demonstrate an atypical process of gelation that has been characterized by regular and stochastically modulated differential scanning calorimetry (DSC) as well as by isoconversional kinetic analysis. The process is detectable as an exothermic peak in the total heat flow of regular DSC and in the nonreversing heat flow of stochastically modulated DSC. Isoconversional kinetic analysis applied to DSC data reveals that the effective activation energy of the process increases from approximately 75 to 200 kJ mol(-1) as a supercooled solution transforms to gel on continuous heating. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. End-of-life resource recovery from emerging electronic products

    DEFF Research Database (Denmark)

    Parajuly, Keshav; Habib, Komal; Cimpan, Ciprian

    2016-01-01

    Integrating product design with appropriate end-of-life (EoL) processing is widely recognized to have huge potentials in improving resource recovery from electronic products. In this study, we investigate both the product characteristics and EoL processing of robotic vacuum cleaner (RVC), as a case...... of emerging electronic product, in order to understand the recovery fate of different materials and its linkage to product design. Ten different brands of RVC were dismantled and their material composition and design profiles were studied. Another 125 RVCs (349 kg) were used for an experimental trial...... at a conventional ‘shred-and-separate’ type preprocessing plant in Denmark. A detailed material flow analysis was performed throughout the recycling chain. The results show a mismatch between product design and EoL processing, and the lack of practical implementation of ‘Design for EoL’ thinking. In the best...

  13. Analysis of Human Resources Management Strategy in China Electronic Commerce Enterprises

    Science.gov (United States)

    Shao, Fang

    The paper discussed electronic-commerce's influence on enterprise human resources management, proposed and proved the human resources management strategy which electronic commerce enterprise should adopt from recruitment strategy to training strategy, keeping talent strategy and other ways.

  14. Effects of Electronic Information Resources Skills Training for Lecturers on Pedagogical Practices and Research Productivity

    Science.gov (United States)

    Bhukuvhani, Crispen; Chiparausha, Blessing; Zuvalinyenga, Dorcas

    2012-01-01

    Lecturers use various electronic resources at different frequencies. The university library's information literacy skills workshops and seminars are the main sources of knowledge of accessing electronic resources. The use of electronic resources can be said to have positively affected lecturers' pedagogical practices and their work in general. The…

  15. Electronic Resources and Mission Creep: Reorganizing the Library for the Twenty-First Century

    Science.gov (United States)

    Stachokas, George

    2009-01-01

    The position of electronic resources librarian was created to serve as a specialist in the negotiation of license agreements for electronic resources, but mission creep has added more functions to the routine work of electronic resources such as cataloging, gathering information for collection development, and technical support. As electronic…

  16. Oxalyl retro-peptide gelators. Synthesis, gelation properties and stereochemical effects.

    Science.gov (United States)

    Makarević, Janja; Jokić, Milan; Frkanec, Leo; Caplar, Vesna; Sijaković Vujičić, Nataša; Zinić, Mladen

    2010-10-04

    In this work we report on gelation properties, self-assembly motifs, chirality effects and morphological characteristics of gels formed by chiral retro-dipeptidic gelators in the form of terminal diacids (1a-5a) and their dimethyl ester (1b-5b) and dicarboxamide (1c-5c) derivatives. Terminal free acid retro-dipeptides (S,S)-bis(LeuLeu) 1a, (S,S)-bis(PhgPhg) 3a and (S,S)-bis(PhePhe) 5a showed moderate to excellent gelation of highly polar water/DMSO and water/DMF solvent mixtures. Retro-peptides incorporating different amino acids (S,S)-(LeuPhg) 2a and (S,S)-(PhgLeu) 4a showed no or very weak gelation. Different gelation effectiveness was found for racemic and single enantiomer gelators. The heterochiral (S,R)-1c diastereoisomer is capable of immobilizing up to 10 and 4 times larger volumes of dichloromethane/DMSO and toluene/DMSO solvent mixtures compared to homochiral (S,S)-1c. Based on the results of (1)H NMR, FTIR, CD investigations, molecular modeling and XRPD studies of diasteroisomeric diesters (S,S)-1b/(S,R)-1b and diacids (S,S)-1b/(S,R)-1a, a basic packing model in their gel aggregates is proposed. The intermolecular hydrogen bonding between extended gelator molecules utilizing both, the oxalamide and peptidic units and layered organization were identified as the most likely motifs appearing in the gel aggregates. Molecular modeling studies of (S,S)-1a/(S,R)-1a and (S,S)-1b/(S,R)-1b diasteroisomeric pairs revealed a decisive stereochemical influence yielding distinctly different low energy conformations: those of (S,R)-diastereoisomers with lipophilic i-Bu groups and polar carboxylic acid or ester groups located on the opposite sides of the oxalamide plane resembling bola amphiphilic structures and those of (S,S)-diasteroisomers possessing the same groups located at both sides of the oxalamide plane. Such conformational characteristics were found to strongly influence both, gelator effectiveness and morphological characteristics of gel aggregates.

  17. Oxalyl retro-peptide gelators. Synthesis, gelation properties and stereochemical effects

    Directory of Open Access Journals (Sweden)

    Janja Makarević

    2010-10-01

    Full Text Available In this work we report on gelation properties, self-assembly motifs, chirality effects and morphological characteristics of gels formed by chiral retro-dipeptidic gelators in the form of terminal diacids (1a–5a and their dimethyl ester (1b–5b and dicarboxamide (1c–5c derivatives. Terminal free acid retro-dipeptides (S,S-bis(LeuLeu 1a, (S,S-bis(PhgPhg 3a and (S,S-bis(PhePhe 5a showed moderate to excellent gelation of highly polar water/DMSO and water/DMF solvent mixtures. Retro-peptides incorporating different amino acids (S,S-(LeuPhg 2a and (S,S-(PhgLeu 4a showed no or very weak gelation. Different gelation effectiveness was found for racemic and single enantiomer gelators. The heterochiral (S,R-1c diastereoisomer is capable of immobilizing up to 10 and 4 times larger volumes of dichloromethane/DMSO and toluene/DMSO solvent mixtures compared to homochiral (S,S-1c. Based on the results of 1H NMR, FTIR, CD investigations, molecular modeling and XRPD studies of diasteroisomeric diesters (S,S-1b/(S,R-1b and diacids (S,S-1b/(S,R-1a, a basic packing model in their gel aggregates is proposed. The intermolecular hydrogen bonding between extended gelator molecules utilizing both, the oxalamide and peptidic units and layered organization were identified as the most likely motifs appearing in the gel aggregates. Molecular modeling studies of (S,S-1a/(S,R-1a and (S,S-1b/(S,R-1b diasteroisomeric pairs revealed a decisive stereochemical influence yielding distinctly different low energy conformations: those of (S,R-diastereoisomers with lipophilic i-Bu groups and polar carboxylic acid or ester groups located on the opposite sides of the oxalamide plane resembling bola amphiphilic structures and those of (S,S-diasteroisomers possessing the same groups located at both sides of the oxalamide plane. Such conformational characteristics were found to strongly influence both, gelator effectiveness and morphological characteristics of gel aggregates.

  18. Preparation of nuclear fuel spheres by flotation-internal gelation

    Science.gov (United States)

    Haas, P.A.; Fowler, V.L.; Lloyd, M.H.

    1984-12-21

    A simplified internal gelation process is claimed for the preparation of gel spheres of nuclear fuels. The process utilizes perchloroethylene as a gelation medium. Gelation is accomplished by directing droplets of a nuclear fuel broth into a moving volume of hot perchloroethylene (about 85/sup 0/C) in a trough. Gelation takes place as the droplets float on the surface of the perchloroethylene and the resultant gel spheres are carried directly into an ager column which is attached to the trough. The aged spheres are disengaged from the perchloroethylene on a moving screen and are deposited in an aqueous wash column. 3 figs.

  19. Electronic Document Management: A Human Resource Management Case Study

    Directory of Open Access Journals (Sweden)

    Thomas Groenewald

    2004-11-01

    Full Text Available This case study serve as exemplar regarding what can go wrong with the implementation of an electronic document management system. Knowledge agility and knowledge as capital, is outlined against the backdrop of the information society and knowledge economy. The importance of electronic document management and control is sketched thereafter. The literature review is concluded with the impact of human resource management on knowledge agility, which includes references to the learning organisation and complexity theory. The intervention methodology, comprising three phases, follows next. The results of the three phases are presented thereafter. Partial success has been achieved with improving the human efficacy of electronic document management, however the client opted to discontinue the system in use. Opsomming Die gevalle studie dien as voorbeeld van wat kan verkeerd loop met die implementering van ’n elektroniese dokumentbestuur sisteem. Teen die agtergrond van die inligtingsgemeenskap en kennishuishouding word kennissoepelheid en kennis as kapitaal bespreek. Die literatuurstudie word afgesluit met die inpak van menslikehulpbronbestuur op kennissoepelheid, wat ook die verwysings na die leerorganisasie en kompleksietydsteorie insluit. Die metodologie van die intervensie, wat uit drie fases bestaan, volg daarna. Die resultate van die drie fases word vervolgens aangebied. Slegs gedeelte welslae is behaal met die verbetering van die menslike doeltreffendheid ten opsigte van elektroniese dokumentbestuur. Die klient besluit egter om nie voort te gaan om die huidige sisteem te gebruik nie.

  20. Evaluation of polyacrylamide gels with accelerator ammonium salts for water shutoff in ultralow temperature reservoirs: Gelation performance and application recommendations

    Directory of Open Access Journals (Sweden)

    Hu Jia

    2016-03-01

    Full Text Available Water shutoff in ultralow temperature reservoirs has received great attention in recent years. In previous study, we reported a phenol-formaldehyde-based gel formula with ammonium salt which can provide a gelation time between 2 hrs and 2 days at 25 °C. However, systematic evaluation and field recommendations of this gel formula when encountering complex reservoirs environment are not addressed. In this paper, how and why such practical considerations as water composition, temperature, pH, weight ratio of formaldehyde to resorcinol and contaminant Fe3+ to affect the gelation performance are examined. Brookfield DV-III and scanning electron microscopy (SEM are employed respectively for viscosity measurement and microstructure analysis. SEM results further illustrate the mechanism of the effect of salinity on gelation performance. It reveals that crosslinking done by covalent bond has great advantage for gel stability under high salinity environment. The target gel formula can provide desirable gelation time below 60 °C, perfect for 15–45 °C, while it is unfeasible to use high salinity to delay gelation at 60 °C. We summarized the effect of salinity on gelation performance of different gel formulas from the present study and published literature. The summarized data can provide important guideline for gel formula design before conducting any kinds of experiments. The variation of gelation performance at different salinity may be dominated by the interaction between crosslinker-salt-polymer, not only limited to “charge-screening effect” and “ion association” proposed by several authors. We hope the analysis encouraging further investigations. Some recommendations for field application of this gel are given in the end of this paper.

  1. Gelation induced supramolecular chirality: chirality transfer, amplification and application.

    Science.gov (United States)

    Duan, Pengfei; Cao, Hai; Zhang, Li; Liu, Minghua

    2014-08-14

    Supramolecular chirality defines chirality at the supramolecular level, and is generated from the spatial arrangement of component molecules assembling through non-covalent interactions such as hydrogen bonding, van der Waals interactions, π-π stacking, hydrophobic interactions and so on. During the formation of low molecular weight gels (LMWGs), one kind of fascinating soft material, one frequently encounters the phenomenon of chirality as well as chiral nanostructures, either from chiral gelators or even achiral gelators. A view of gelation-induced supramolecular chirality will be very helpful to understand the self-assembly process of the gelator molecules as well as the chiral structures, the regulation of the chirality in the gels and the development of the "smart" chiral materials such as chiroptical devices, catalysts and chiral sensors. It necessitates fundamental understanding of chirality transfer and amplification in these supramolecular systems. In this review, recent progress in gelation-induced supramolecular chirality is discussed.

  2. Rotational and translational diffusions of fluorescent probes during gelation process

    Science.gov (United States)

    Hattori, Yusuke; Panizza, Pascal; Letamendia, Louis; Ushiki, Hideharu

    2006-04-01

    Gelation process has been investigated by using light scattering techniques in recent years. We measured both of rotational and translational motions of fluorescent probes during gelation process. The measurements were performed after the temperature quenched at 30 °C. As the results, rotational diffusion coefficient of fluorescein was decreased after 6.0 × 10 4 s and energy transfer rate was reduced after 2.0 × 10 4 s. We sorted the gelation process into the following three parts, (I) pre-gelation, (II) reduction of translational diffusion (aging), and (III) reduction of rotational diffusion with saturating translational diffusion (post-gelation). The time scale of the process was completely different from the results of other methods.

  3. Gelation And Mechanical Response of Patchy Rods

    Science.gov (United States)

    Kazem, Navid; Majidi, Carmel; Maloney, Craig

    We perform Brownian Dynamics simulations to study the gelation of suspensions of attractive, rod-like particles. We show that details of the particle-particle interactions can dramatically affect the dynamics of gelation and the structure and mechanics of the networks that form. If the attraction between the rods is perfectly smooth along their length, they will collapse into compact bundles. If the attraction is sufficiently corrugated or patchy, over time, a rigid space spanning network forms. We study the structure and mechanical properties of the networks that form as a function of the fraction of the surface that is allowed to bind. Surprisingly, the structural and mechanical properties are non-monotonic in the surface coverage. At low coverage, there are not a sufficient number of cross-linking sites to form networks. At high coverage, rods bundle and form disconnected clusters. At intermediate coverage, robust networks form. The elastic modulus and yield stress are both non-monotonic in the surface coverage. The stiffest and strongest networks show an essentially homogeneous deformation under strain with rods re-orienting along the extensional axis. Weaker, clumpy networks at high surface coverage exhibit relatively little re-orienting with strong non-affine deformation. These results suggest design strategies for tailoring surface interactions between rods to yield rigid networks with optimal properties. National Science Foundation and the Air Force Office of Scientific Research.

  4. Uranium kernel formation via internal gelation

    International Nuclear Information System (INIS)

    Hunt, R.D.; Collins, J.L.

    2004-01-01

    In the 1970s and 1980s, U.S. Department of Energy (DOE) conducted numerous studies on the fabrication of nuclear fuel particles using the internal gelation process. These amorphous kernels were prone to flaking or breaking when gases tried to escape from the kernels during calcination and sintering. These earlier kernels would not meet today's proposed specifications for reactor fuel. In the interim, the internal gelation process has been used to create hydrous metal oxide microspheres for the treatment of nuclear waste. With the renewed interest in advanced nuclear fuel by the DOE, the lessons learned from the nuclear waste studies were recently applied to the fabrication of uranium kernels, which will become tri-isotropic (TRISO) fuel particles. These process improvements included equipment modifications, small changes to the feed formulations, and a new temperature profile for the calcination and sintering. The modifications to the laboratory-scale equipment and its operation as well as small changes to the feed composition increased the product yield from 60% to 80%-99%. The new kernels were substantially less glassy, and no evidence of flaking was found. Finally, key process parameters were identified, and their effects on the uranium microspheres and kernels are discussed. (orig.)

  5. Combination of high-performance refractometry and infrared spectroscopy as a probe for chemically induced gelation and vitrification of epoxies

    International Nuclear Information System (INIS)

    Mueller, U; Philipp, M; Gervais, P-C; Sanctuary, R; Krueger, J K; Possart, W; Wehlack, C; Kieffer, J

    2010-01-01

    A combination of infrared spectroscopy and high-performance refractometry was used to investigate the chemically induced sol-gel and glass transition during the polymerization of epoxies. Representations of the refractive index versus chemical conversion reveal an interesting insight into the optical properties accompanying gelation and vitrification. Whereas the electronic polarizability of the liquid state of small average molecular mass and the glassy state is dominated by the mass density, an unexpected excess polarizability observed during the gelation is attributed to cooperative dipole-dipole interactions.

  6. Combination of high-performance refractometry and infrared spectroscopy as a probe for chemically induced gelation and vitrification of epoxies

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, U; Philipp, M; Gervais, P-C; Sanctuary, R; Krueger, J K [Laboratoire de Physique des Materiaux, Universite du Luxembourg, 162A avenue de la faiencerie, L-1511 Luxembourg (Luxembourg); Possart, W; Wehlack, C [Fachbereich Werkstoffwissenschaften, Universitaet des Saarlandes, D-66123 Saarbruecken (Germany); Kieffer, J, E-mail: ulrich.mueller@uni.l [Department of Materials Science and Engineering, University of Michigan, Ann Arbor, MI (United States)

    2010-08-15

    A combination of infrared spectroscopy and high-performance refractometry was used to investigate the chemically induced sol-gel and glass transition during the polymerization of epoxies. Representations of the refractive index versus chemical conversion reveal an interesting insight into the optical properties accompanying gelation and vitrification. Whereas the electronic polarizability of the liquid state of small average molecular mass and the glassy state is dominated by the mass density, an unexpected excess polarizability observed during the gelation is attributed to cooperative dipole-dipole interactions.

  7. Electronic Safety Resource Tools -- Supporting Hydrogen and Fuel Cell Commercialization

    Energy Technology Data Exchange (ETDEWEB)

    Barilo, Nick F.

    2014-09-29

    The Pacific Northwest National Laboratory (PNNL) Hydrogen Safety Program conducted a planning session in Los Angeles, CA on April 1, 2014 to consider what electronic safety tools would benefit the next phase of hydrogen and fuel cell commercialization. A diverse, 20-person team led by an experienced facilitator considered the question as it applied to the eight most relevant user groups. The results and subsequent evaluation activities revealed several possible resource tools that could greatly benefit users. The tool identified as having the greatest potential for impact is a hydrogen safety portal, which can be the central location for integrating and disseminating safety information (including most of the tools identified in this report). Such a tool can provide credible and reliable information from a trustworthy source. Other impactful tools identified include a codes and standards wizard to guide users through a series of questions relating to application and specific features of the requirements; a scenario-based virtual reality training for first responders; peer networking tools to bring users from focused groups together to discuss and collaborate on hydrogen safety issues; and a focused tool for training inspectors. Table ES.1 provides results of the planning session, including proposed new tools and changes to existing tools.

  8. Ultrasound- and Temperature-Induced Gelation of Gluconosemicarbazide Gelator in DMSO and Water Mixtures

    Directory of Open Access Journals (Sweden)

    Mothukunta Himabindu

    2017-04-01

    Full Text Available We have developed amphiphilic supramolecular gelators carrying glucose moiety that could gel a mixture of dimethyl sulfoxide (DMSO and water upon heating as well as ultrasound treatment. When the suspension of gluconosemicarbazide was subjected to ultrasound treatment, gelation took place at much lower concentrations compared to thermal treatment, and the gels transformed into a solution state at higher temperatures compared to temperature-induced gels. The morphology was found to be influenced by the nature of the stimulus and presence of salts such as KCl, NaCl, CaCl2 and surfactant (sodium dodecyl sulphate at a concentration of 0.05 M. The gel exhibited impressive tolerance to these additives, revealing the stability and strength of the gels. Fourier transform infrared spectroscopy (FTIR revealed the presence of the intermolecular hydrogen bonding interactions while differential scanning calorimetry (DSC and rheological studies supported better mechanical strength of ultrasound-induced (UI gels over thermally-induced (TI gels.

  9. Controlling user access to electronic resources without password

    Science.gov (United States)

    Smith, Fred Hewitt

    2015-06-16

    Described herein are devices and techniques for remotely controlling user access to a restricted computer resource. The process includes pre-determining an association of the restricted computer resource and computer-resource-proximal environmental information. Indicia of user-proximal environmental information are received from a user requesting access to the restricted computer resource. Received indicia of user-proximal environmental information are compared to associated computer-resource-proximal environmental information. User access to the restricted computer resource is selectively granted responsive to a favorable comparison in which the user-proximal environmental information is sufficiently similar to the computer-resource proximal environmental information. In at least some embodiments, the process further includes comparing user-supplied biometric measure and comparing it with a predetermined association of at least one biometric measure of an authorized user. Access to the restricted computer resource is granted in response to a favorable comparison.

  10. The Internet School of Medicine: use of electronic resources by medical trainees and the reliability of those resources.

    Science.gov (United States)

    Egle, Jonathan P; Smeenge, David M; Kassem, Kamal M; Mittal, Vijay K

    2015-01-01

    Electronic sources of medical information are plentiful, and numerous studies have demonstrated the use of the Internet by patients and the variable reliability of these sources. Studies have investigated neither the use of web-based resources by residents, nor the reliability of the information available on these websites. A web-based survey was distributed to surgical residents in Michigan and third- and fourth-year medical students at an American allopathic and osteopathic medical school and a Caribbean allopathic school regarding their preferred sources of medical information in various situations. A set of 254 queries simulating those faced by medical trainees on rounds, on a written examination, or during patient care was developed. The top 5 electronic resources cited by the trainees were evaluated for their ability to answer these questions accurately, using standard textbooks as the point of reference. The respondents reported a wide variety of overall preferred resources. Most of the 73 responding medical trainees favored textbooks or board review books for prolonged studying, but electronic resources are frequently used for quick studying, clinical decision-making questions, and medication queries. The most commonly used electronic resources were UpToDate, Google, Medscape, Wikipedia, and Epocrates. UpToDate and Epocrates had the highest percentage of correct answers (47%) and Wikipedia had the lowest (26%). Epocrates also had the highest percentage of wrong answers (30%), whereas Google had the lowest percentage (18%). All resources had a significant number of questions that they were unable to answer. Though hardcopy books have not been completely replaced by electronic resources, more than half of medical students and nearly half of residents prefer web-based sources of information. For quick questions and studying, both groups prefer Internet sources. However, the most commonly used electronic resources fail to answer clinical queries more than half

  11. Developing Humanities Collections in the Digital Age: Exploring Humanities Faculty Engagement with Electronic and Print Resources

    Science.gov (United States)

    Kachaluba, Sarah Buck; Brady, Jessica Evans; Critten, Jessica

    2014-01-01

    This article is based on quantitative and qualitative research examining humanities scholars' understandings of the advantages and disadvantages of print versus electronic information resources. It explores how humanities' faculty members at Florida State University (FSU) use print and electronic resources, as well as how they perceive these…

  12. Chitosan microparticles: influence of the gelation process on the release profile and oral bioavailability of albendazole, a class II compound.

    Science.gov (United States)

    Piccirilli, Gisela N; García, Agustina; Leonardi, Darío; Mamprin, María E; Bolmaro, Raúl E; Salomón, Claudio J; Lamas, María C

    2014-11-01

    Encapsulation of albendazole, a class II compound, into polymeric microparticles based on chitosan-sodium lauryl sulfate was investigated as a strategy to improve drug dissolution and oral bioavailability. The microparticles were prepared by spray drying technique and further characterized by means of X-ray powder diffractometry, infrared spectroscopy and scanning electron microscopy. The formation of a novel polymeric structure between chitosan and sodium lauryl sulfate, after the internal or external gelation process, was observed by infrared spectroscopy. The efficiency of encapsulation was found to be between 60 and 85% depending on the internal or external gelation process. Almost spherically spray dried microparticles were observed using scanning electron microscopy. In vitro dissolution results indicated that the microparticles prepared by internal gelation released 8% of the drug within 30 min, while the microparticles prepared by external gelation released 67% within 30 min. It was observed that the AUC and Cmax values of ABZ from microparticles were greatly improved, in comparison with the non-encapsulated drug. In conclusion, the release properties and oral bioavailability of albendazole were greatly improved by using spraydried chitosan-sodium lauryl sulphate microparticles.

  13. Electronic resource management practical perspectives in a new technical services model

    CERN Document Server

    Elguindi, Anne

    2012-01-01

    A significant shift is taking place in libraries, with the purchase of e-resources accounting for the bulk of materials spending. Electronic Resource Management makes the case that technical services workflows need to make a corresponding shift toward e-centric models and highlights the increasing variety of e-formats that are forcing new developments in the field.Six chapters cover key topics, including: technical services models, both past and emerging; staffing and workflow in electronic resource management; implementation and transformation of electronic resource management systems; the ro

  14. Organic Gelators as Growth Control Agents for Stable and Reproducible Hybrid Perovskite-Based Solar Cells

    KAUST Repository

    Masi, Sofia

    2017-03-03

    Low-molecular-weight organic gelators are widely used to influence the solidification of polymers, with applications ranging from packaging items, food containers to organic electronic devices, including organic photovoltaics. Here, this concept is extended to hybrid halide perovskite-based materials. In situ time-resolved grazing incidence wide-angle X-ray scattering measurements performed during spin coating reveal that organic gelators beneficially influence the nucleation and growth of the perovskite precursor phase. This can be exploited for the fabrication of planar n-i-p heterojunction devices with MAPbI3 (MA = CH3NH3+) that display a performance that not only is enhanced by ≈25% compared to solar cells where the active layer is produced without the use of a gelator but that also features a higher stability to moisture and a reduced hysteresis. Most importantly, the presented approach is straightforward and simple, and it provides a general method to render the film formation of hybrid perovskites more reliable and robust, analogous to the control that is afforded by these additives in the processing of commodity “plastics.”

  15. Electronic resources access and usage among the postgraduates of ...

    African Journals Online (AJOL)

    ... and usage among the postgraduates of a Nigerian University of Technology. ... faced by postgraduates in using e-resources include takes too much time to find, ... Resources, Access, Use, Postgraduat, Students, University, Technology, Nigeria ... By Country · List All Titles · Free To Read Titles This Journal is Open Access.

  16. Strategic Planning for Electronic Resources Management: A Case Study at Gustavus Adolphus College

    Science.gov (United States)

    Hulseberg, Anna; Monson, Sarah

    2009-01-01

    Electronic resources, the tools we use to manage them, and the needs and expectations of our users are constantly evolving; at the same time, the roles, responsibilities, and workflow of the library staff who manage e-resources are also in flux. Recognizing a need to be more intentional and proactive about how we manage e-resources, the…

  17. impact of the use of electronic resources on research output

    African Journals Online (AJOL)

    manda

    ... Julita Nawe. University of Dar Es Salaam Library, P.O. Box 35092, Dar Es Salaam, Tanzania .... significantly, while 28.3% observed that quality of service to the community had improved .... resources and evaluate them is an important area.

  18. Preservation of and Permanent Access to Electronic Information Resources

    National Research Council Canada - National Science Library

    Hodge, Gail

    2004-01-01

    The rapid growth in the creation and dissemination of electronic information has emphasized the digital environment's speed and ease of dissemination with little regard for its long-term preservation and access...

  19. Electronic conferencing for continuing medical education: a resource survey.

    Science.gov (United States)

    Sternberg, R J

    1986-10-01

    The use of electronic technologies to link participants for education conferences is an option for providers of Continuing Medical Education. In order to profile the kinds of electronic networks currently offering audio- or videoteleconferences for physician audiences, a survey was done during late 1985. The information collected included range of services, fees, and geographic areas served. The results show a broad diversity of providers providing both interactive and didactic programming to both physicians and other health care professionals.

  20. Controlling user access to electronic resources without password

    Science.gov (United States)

    Smith, Fred Hewitt

    2017-08-22

    Described herein are devices and techniques for remotely controlling user access to a restricted computer resource. The process includes obtaining an image from a communication device of a user. An individual and a landmark are identified within the image. Determinations are made that the individual is the user and that the landmark is a predetermined landmark. Access to a restricted computing resource is granted based on the determining that the individual is the user and that the landmark is the predetermined landmark. Other embodiments are disclosed.

  1. Electron beam pasteurised oil palm waste: a potential feed resource

    International Nuclear Information System (INIS)

    Mat Rasol Awang; Hassan Hamdani Mutaat; Tamikazu Kume; Tachibana, H.

    2002-01-01

    Pasteurization of oil palm empty fruit bunch (EFB) was performed using electron beam single sided irradiation. The dose profiles of oil palm EFB samples for different thickness in both directions X and Y were established. The results showed the usual characteristics dose uniformity as sample thickness decreased. The mean average absorbed dose on both sides at the surface and bottom of the samples for different thickness samples lead to establishing depth dose curve. Based on depth dose curve and operation conditions of electron beam machine, the process throughput for pasteurized oil palm EFB were estimated. (Author)

  2. Availability of Electronic Resources for Service Provision in ...

    African Journals Online (AJOL)

    The study also revealed that majority of the University libraries have adequate basic infrastructure for effective electronic information services. ... acquired by the library are put into maximal use by the library clientele, thereby ensuring the achievement of the library's objective which is satisfying the users, information needs.

  3. Utilization of bio-resources by low energy electron beam

    International Nuclear Information System (INIS)

    Kume, Tamikazu

    2003-01-01

    Utilization of bio-resources by radiation has been investigated for recycling the natural resources and reducing the environmental pollution. Polysaccharides such as chitosan and sodium alginate were easily degraded by irradiation and induced various kinds of biological activities, i.g. anti-microbial activity, promotion of plant growth, suppression of heavy metal stress, phytoalexins induction. Radiation degraded chitosan was effective to enhance the growth of plants in tissue culture. It was demonstrated that the liquid sample irradiation system using low energy EB was effective for the preparation of degraded polysaccharides. Methylcellulose (MC) can be crosslinked under certain radiation condition as same as carboxymethylcellulose (CMC) and produced the biodegradable hydrogel for medical and agricultural use. Treatment of soybean seeds by low energy EB enhanced the growth and the number of rhizobia on the root. (author)

  4. Analysis of Pedagogic Potential of Electronic Educational Resources with Elements of Autodidactics

    Directory of Open Access Journals (Sweden)

    Igor A.

    2018-03-01

    Full Text Available Introduction: in recent years didactic properties of electronic educational resources undergo considerable changes, nevertheless, the question of studying of such complete phenomenon as “an electronic educational resource with autodidactics elements” remains open, despite sufficient scientific base of researches of the terms making this concept. Article purpose – determination of essence of electronic educational resources with autodidactics elements. Materials and Methods: the main method of research was the theoretical analysis of the pedagogical and psychological literature on the problem under study. We used the theoretical (analysis, synthesis, comparison and generalization methods, the method of interpretation, pedagogical modeling, and empirical methods (observation, testing, conversation, interview, analysis of students’ performance, pedagogical experiment, peer review. Results: we detected the advantages of electronic educational resources in comparison with traditional ones. The concept of autodidactics as applied to the subject of research is considered. Properties of electronic educational resources with a linear and nonlinear principle of construction are studied.The influence of the principle of construction on the development of the learners’ qualities is shown. We formulated an integral definition of electronic educational resources with elements of autodidactics, namely, the variability, adaptivity and cyclicity of training. A model of the teaching-learning process with electronic educational resources is developed. Discussion and Conclusions: further development of a problem will allow to define whether electronic educational resources with autodidactics elements pedagogical potential for realization of educational and self-educational activity of teachers have, to modify technological procedures taking into account age features of students, their specialties and features of the organization of process of training of

  5. A Study on Developing Evaluation Criteria for Electronic Resources in Evaluation Indicators of Libraries

    Science.gov (United States)

    Noh, Younghee

    2010-01-01

    This study aimed to improve the current state of electronic resource evaluation in libraries. While the use of Web DB, e-book, e-journal, and other e-resources such as CD-ROM, DVD, and micro materials is increasing in libraries, their use is not comprehensively factored into the general evaluation of libraries and may diminish the reliability of…

  6. Managing Selection for Electronic Resources: Kent State University Develops a New System to Automate Selection

    Science.gov (United States)

    Downey, Kay

    2012-01-01

    Kent State University has developed a centralized system that manages the communication and work related to the review and selection of commercially available electronic resources. It is an automated system that tracks the review process, provides selectors with price and trial information, and compiles reviewers' feedback about the resource. It…

  7. Photothermal characterization of the gelation process in Gelidium robustum Agar

    Science.gov (United States)

    Freile-Pelegrín, Y.; Bante, J.; Alvarado-Gil, J. J.; Yánez-Limón, J. M.

    2005-06-01

    Agar is a hydrophilic colloid formed by polysaccharides, whose ability to form reversible gels simply by cooling hot aqueous solutions is the most important property and can be regarded as the prototype and model for all gelling systems. In this paper the evolution of the gelation process of agar obtained from algae of the species Gelidium robustum, using the photopyroelectric technique is reported. It is shown that thermal effusivity increase when the agar is cooled, reaching a maximum value around 37°C. The increase in thermal effusivity can be related to the increasing of the bondings in the gel as temperature decreases, reaching the maximum at the gelation point. The decrease of the thermal effusivity at lower temperature could be due to the syneresis process involving a gradual release of water after gelation.

  8. Chemical flowsheet conditions for preparing urania spheres by internal gelation

    International Nuclear Information System (INIS)

    Haas, P.A.; Begovich, J.M.; Ryon, A.D.; Vavruska, J.S.

    1979-01-01

    Small, ceramic urania spheres can be prepared for use as nuclear fuel by internal chemical gelation of uranyl nitrate solution droplets. Decomposition of hexamethylenetetramine (HMTA) dissolved in the uranyl nitrate solution releases ammonia to precipitate hydrated UO 3 . Previously established flowsheet conditions have been improved and modified at ORNL and have been applied to prepare dense UO 2 spheres with average diameters of 1200, 300, and 30 μm. Acid-deficient uranyl nitrate (ADUN) solutions up to 3.4 M in uranium with NO 3 - /U mole ratios of 1.5 to 1.7 are prepared by dissolution of U 3 O 8 or UO 3 . Continuous mixing of metered, cooled ADUN containing urea and HMTA solutions provides a smooth, regulated flow of the temperature-sensitive feed solution. The gelation times for solution drops in organic liquids at 45 to 95 0 C depend on both the chemical reaction rates and the rates of heat transfer. The gel properties vary with temperature and other gelation variables. Gelation conditions were determined which allow easy washing, drying, firing, and sintering to produce dense UO 2 spheres of all three sizes. The 1200- and 300-μm UO 2 spheres were pepared by gelation in trichloroethylene at 50 to 65 0 C; 2-ethyl-l-hexanol was used as the gelation medium to prepare 30-μm UO 2 spheres. Washing and drying requirements were determined. The gel dried to 225 0 C contains about 95% UO 3 ; the remaining components are H 2 O, NH 3 - , which are volatilized during firing to UO 2

  9. Where Do Electronic Books Fit in the College Research Arsenal of Resources?

    Science.gov (United States)

    Barbier, Patricia

    2007-01-01

    Student use of electronic books has become an accepted supplement to traditional resources. Student use and satisfaction was monitored through an online course discussion board. Increased use of electronic books indicate this service is an accepted supplement to the print book collection.

  10. UO2 microspheres obtainment through the internal gelation methods

    International Nuclear Information System (INIS)

    Sterba, M.E.; Gomez Constenla, A.

    1987-01-01

    UO 2 microspheres obtainment process through the internal gelation method which allows the spheres' obtainment of uniform size is detailed herein, varying the same among 0.3 and 1.7 mm of diameter. The sintered density reaches 10.78 g/cm 3 , permitting the fuels fabrication dispersed and vibro-compacted fuels. The trichloroethylene use implementation as gelation agent is described, thus reducing the number of stages in the microspheres fabrication. At the same time, the uranium sun composition has been modified so as to be compatible with the use solvent. (Author)

  11. The National Site Licensing of Electronic Resources: An Institutional Perspective

    Directory of Open Access Journals (Sweden)

    Xiaohua Zhu

    2011-06-01

    Full Text Available While academic libraries in most countries are struggling to negotiate with publishers and vendors individually or collaboratively via consortia, a few countries have experimented with a different model, national site licensing (NSL. Because NSL often involves government and large-scale collaboration, it has the potential to solve many problems in the complex licensing world. However, not many nations have adopted it. This study uses historical research approach and the comparative case study research method to explore the seemingly low level of adoption. The cases include the Canadian National Site Licensing Project (CNSLP, the United Kingdom’s National Electronic Site Licensing Initiative (NESLI, and the United States, which has not adopted NSL. The theoretical framework guiding the research design and data collection is W. Richard Scott’s institutional theory, which utilizes three supporting pillars—regulative, normative, and cultural-cognitive—to analyze institutional processes. In this study, the regulative pillar and the normative pillar of NSL adoption— an institutional construction and change—are examined. Data were collected from monographs, research articles, government documents, and relevant websites. Based on the analysis of these cases, a preliminary model is proposed for the adoption of NSL. The factors that support a country’s adoption of NSL include the need for new institutions, a centralized educational policy-making system and funding system, supportive political trends, and the tradition of cooperation. The factors that may prevent a country from adopting NSL include decentralized educational policy and funding, diversity and the large number of institutions, the concern for the “Big Deal,” and the concern for monopoly.

  12. Comparison of the sickling and gelation properties of acidic ...

    African Journals Online (AJOL)

    The effects of acidic metabolites of A. vera and C. cajan extracts on the sickling and gelation times of human HbSS erythrocytes were investigated to obtain a better understanding of the anti-sickling compounds contained in them for use in the management of sickle cell disease. The results obtained showed that the acidic ...

  13. Use of different additives to improve low quality surimi gelation.

    Directory of Open Access Journals (Sweden)

    Deysi Cando

    2014-06-01

    In conclusion, in general, the physicochemical and viscoelastic properties of gels were improved by the addition of both ingredients, giving stronger gels even at very low level of salt. These results indicate that both ingredients, which do not add calories to the final gels, can be used as a good alternative for the better gelation of the low quality surimis.

  14. Conductive Screen Printing Inks by Gelation of Graphene Dispersions

    NARCIS (Netherlands)

    Arapov, K.; Rubingh, E.; Abbel, R.J.; Laven, J.; With, G. de; Friedrich, H.

    2016-01-01

    This paper describes the gelation of highly concentrated graphene/polymer dispersions triggered by mild heating. The gel formation is only dependent on the concentration of graphene with 3.25 mg mL-1 as the minimum value for graphene network formation. The graphene gel is then utilized for the

  15. Non-Steroidal Biphenyl Gelators: Correlation of Xerogel Structure with Solid-State Structure and Circular Dichroism Spectroscopy

    Directory of Open Access Journals (Sweden)

    H. Cristina Geiger

    2018-04-01

    Full Text Available Because the factors favoring the formation of well-formed single crystals are dissimilar to those conducive to gel formation, few examples of single-crystal structural characterizations of organogelators are found in the literature. A series of biphenyl methyl and ethyl diester derivatives of varying chain length were synthesized and their gelation abilities explored. X-ray diffraction of single crystals of one of the gelators reveals a columnar extended structure. Based on XRD results for xerogels obtained from the reported organogelators, the members of the series are isostructural and so also adopt a columnar superstructure. Scanning electron microscopy (SEM was used for the investigation of the morphology of the xerogels, which display either platelet-like morphologies or more typical entangled twisted ribbon-like aggregates. The gels exhibit chirality, which depends on the sol-gel transition history, as observed by induced circular dichroism (ICD spectroscopy.

  16. Internal gelation at PSI. The past and the future

    International Nuclear Information System (INIS)

    Pouchon, Manuel A.; Ingold, Franz

    2009-01-01

    The Paul Scherrer Institute used to be very active in fuel fabrication R and D using the internal gelation process, which is a promising production method for spherical nuclear fuel. Such fuel kernels can be directly packed in a cylindrical cladding (a sphere-pac pin), or they can be coated in the TRISO concept. The internal gelation offers several advantages, as it is aqueous up to the forming of the sphere. Consequently, the process is almost dustless, with lower risk of incorporation. The production does not require mechanical and maintenance intensive equipment, as for example presses and grinding machines necessary for pellet type fuel. Especially for low decontaminated fuel coming from aqueous reprocessing, this offers a great advantage, because the production line can easily be handled remotely in a hot cell. In the past, many different fuel matrices were produced and tested at PSI (carbide, nitride and oxide fuels). The paper summarizes the past activities, and some important findings. Furthermore, future perspectives of this concept are shown. These are especially seen in context of Generation IV nuclear systems such as the sodium cooled fast reactor (SFR), the very high temperature reactor (VHTR), and the gas cooled fast reactor (GFR). The paper describes the former production line, which was a classical internal gelation process. Some advantages and disadvantages of this system will be illustrated which lead to a new project at PSI. A silicon oil-free system will be developed over the next years. The oil as a heat carrier is replaced by a cavity, where microwaves act on falling drops and lead to the desired gelation before the spheres drop into a washing solution. The idea of a microwave gelation has already been tested at several laboratories in the past. The paper gives an overview of these activities. Finally the concept of the new production at PSI is introduced. (author)

  17. Effect of food additives on egg yolk gelation induced by freezing.

    Science.gov (United States)

    Primacella, Monica; Fei, Tao; Acevedo, Nuria; Wang, Tong

    2018-10-15

    This study demonstrates technological advances in preventing yolk gelation during freezing and thawing. Gelation negatively affects yolk functionality in food formulation. Preventing gelation using 10% salt or sugar limits the application of the yolk. Novel food additives were tested to prevent gelation induced by freezing. Significant reduction (p freezing at -20 °C) indicates that hydrolyzed carboxymethyl cellulose (HCMC), proline, and hydrolyzed egg white and yolk (HEW and HEY) are effective gelation inhibitors. The mechanisms in which these additives prevented gelation were further studied through measuring the changes in the amount of freezable water, lipoprotein particle size, and protein surface hydrophobicity. Overall, this study provides several alternatives of gelation inhibitor that have great potentials in replacing the use of salt or sugar in commercial operation of freezing egg yolk for shelf-life extension. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. A survey of the use of electronic scientific information resources among medical and dental students

    Directory of Open Access Journals (Sweden)

    Aarnio Matti

    2006-05-01

    Full Text Available Abstract Background To evaluate medical and dental students' utilization of electronic information resources. Methods A web survey sent to 837 students (49.9% responded. Results Twenty-four per cent of medical students and ninteen per cent of dental students searched MEDLINE 2+ times/month for study purposes, and thiry-two per cent and twenty-four per cent respectively for research. Full-text articles were used 2+ times/month by thirty-three per cent of medical and ten per cent of dental students. Twelve per cent of respondents never utilized either MEDLINE or full-text articles. In multivariate models, the information-searching skills among students were significantly associated with use of MEDLINE and full-text articles. Conclusion Use of electronic resources differs among students. Forty percent were non-users of full-text articles. Information-searching skills are correlated with the use of electronic resources, but the level of basic PC skills plays not a major role in using these resources. The student data shows that adequate training in information-searching skills will increase the use of electronic information resources.

  19. Analytical Study of Usage of Electronic Information Resources at Pharmacopoeial Libraries in India

    Directory of Open Access Journals (Sweden)

    Sunil Tyagi

    2014-02-01

    Full Text Available The objective of this study is to know the rate and purpose of the use of e-resource by the scientists at pharmacopoeial libraries in India. Among other things, this study examined the preferences of the scientists toward printed books and journals, electronic information resources, and pattern of using e-resources. Non-probability sampling specially accidental and purposive technique was applied in the collection of primary data through administration of user questionnaire. The sample respondents chosen for the study consists of principle scientific officer, senior scientific officer, scientific officer, and scientific assistant of different division of the laboratories, namely, research and development, pharmaceutical chemistry, pharmacovigilance, pharmacology, pharmacogonosy, and microbiology. The findings of the study reveal the personal experiences and perceptions they have had on practice and research activity using e-resource. The major findings indicate that of the total anticipated participants, 78% indicated that they perceived the ability to use computer for electronic information resources. The data analysis shows that all the scientists belonging to the pharmacopoeial libraries used electronic information resources to address issues relating to drug indexes and compendia, monographs, drugs obtained through online databases, e-journals, and the Internet sources—especially polices by regulatory agencies, contacts, drug promotional literature, and standards.

  20. Considering Point-of-Care Electronic Medical Resources in Lieu of Traditional Textbooks for Medical Education.

    Science.gov (United States)

    Hale, LaDonna S; Wallace, Michelle M; Adams, Courtney R; Kaufman, Michelle L; Snyder, Courtney L

    2015-09-01

    Selecting resources to support didactic courses is a critical decision, and the advantages and disadvantages must be carefully considered. During clinical rotations, students not only need to possess strong background knowledge but also are expected to be proficient with the same evidence-based POC resources used by clinicians. Students place high value on “real world” learning and therefore may place more value on POC resources that they know practicing clinicians use as compared with medical textbooks. The condensed nature of PA education requires students to develop background knowledge and information literacy skills over a short period. One way to build that knowledge and those skills simultaneously is to use POC resources in lieu of traditional medical textbooks during didactic training. Electronic POC resources offer several advantages over traditional textbooks and should be considered as viable options in PA education.

  1. Elektronik Bilgi Kaynaklarının Seçimi / Selection of Electronic Information Resources

    Directory of Open Access Journals (Sweden)

    Pınar Al

    2003-04-01

    Full Text Available For many years, library users have used only from the printed media in order to get the information that they have needed. Today with the widespread use of the Web and the addition of electronic information resources to library collections, the use of information in the electronic environment as well as in printed media is started to be used. In time, such types of information resources as, electronic journals, electronic books, electronic encyclopedias, electronic dictionaries and electronic theses have been added to library collections. In this study, selection criteria that can be used for electronic information resources are discussed and suggestions are provided for libraries that try to select electronic information resources for their collections.

  2. Synthesis and Properties of Gelators Derived from Tetraphenylethylene and Gallic Acid with Aggregation-Induced Emission

    Science.gov (United States)

    Luo, Miao; Zhou, Xie; Chi, Zhenguo; Ma, Chunping; Zhang, Yi; Liu, Siwei; Xu, Jiarui

    2013-09-01

    Two novel organogelators (TEG and TAG) based on tetraphenylethylene and 3,4,5-tris(dodecyloxy) benzoic acid were synthesized through ester bond and amido bond linkages, respectively. Compounds TEG and TAG were able to induce gelation in ethanol. Aggregation-induced enhanced emission was observed in these organogelator molecules, with increased fluorescence intensity from the solutions to the gels. The completely thermoreversible gelation occurred due to the aggregation of the organogelators. In the process, a fibrous network was formed by a combination of intermolecular hydrogen bonding, π-π stacking and van der Waals interactions. These phenomena were observed in the xerogels by field-emission scanning electron microscopy and Fourier-transform infrared spectroscopy. The results of differential scanning calorimetry and polarized optical microscopy indicated that compound TAG exhibited stable liquid crystalline phases over a wide temperature range. The linking groups have severe influence on the properties of the organogelators, which was mainly attributed to the hydrogen bonding interaction in compound TAG.

  3. Effect of co-solute and gelation temperature on milk protein and gum tragacanth interaction in acidified gels.

    Science.gov (United States)

    Hatami, Masoud; Nejatian, Mohammad; Mohammadifar, Mohammad Amin

    2012-05-01

    The aim of this study was to investigate the role of process conditions and system composition on the acid-induced gelation of a mixture of milk protein and gum tragacanth. This was studied by determining the effects of co-solute (lactose) addition (3, 5 and 7%) and gelation temperature (25, 37 and 45°C) on the mixture's rheological properties and microstructure using a combination of techniques including small-deformation rheology and scanning electron microscopy. The presence of lactose played an important role in the microstructure formation of gels but did not change most rheological properties. The microstructure of gels formed in the presence of lactose was coarser and more particulate, but less interconnected; this can be explained by lactose's role in improving protein aggregation. Gels prepared at a lower temperature had a high structure strength, as indicated by their high storage modulus, τ(f) and G(f) values. Low gelation temperature also caused a more branched and homogenous microstructure. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Use of electronic sales data to tailor nutrition education resources for an ethnically diverse population.

    Science.gov (United States)

    Eyles, H; Rodgers, A; Ni Mhurchu, C

    2010-02-01

    Nutrition education may be most effective when personally tailored. Individualised electronic supermarket sales data offer opportunities to tailor nutrition education using shopper's usual food purchases. The present study aimed to use individualised electronic supermarket sales data to tailor nutrition resources for an ethnically diverse population in a large supermarket intervention trial in New Zealand. Culturally appropriate nutrition education resources (i.e. messages and shopping lists) were developed with the target population (through two sets of focus groups) and ethnic researchers. A nutrient database of supermarket products was developed using retrospective sales data and linked to participant sales to allow tailoring by usual food purchases. Modified Heart Foundation Tick criteria were used to identify 'healthier' products in the database suitable for promotion in the resources. Rules were developed to create a monthly report listing the tailored and culturally targeted messages to be sent to each participant, and to produce automated, tailored shopping lists. Culturally targeted nutrition messages (n = 864) and shopping lists (n = 3 formats) were developed. The food and nutrient database (n = 3000 top-selling products) was created using 12 months of retrospective sales data, and comprised 60%'healthier' products. Three months of baseline sales data were used to determine usual food purchases. Tailored resources were successfully mailed to 123 Māori, 52 Pacific and 346 non-Māori non-Pacific participants over the 6-month trial intervention period. Electronic supermarket sales data can be used to tailor nutrition education resources for a large number of ethnically diverse supermarket shoppers.

  5. Rational Design of Molecular Gelator - Solvent Systems Guided by Solubility Parameters

    Science.gov (United States)

    Lan, Yaqi

    Self-assembled architectures, such as molecular gels, have attracted wide interest among chemists, physicists and engineers during the past decade. However, the mechanism behind self-assembly remains largely unknown and no capability exists to predict a priori whether a small molecule will gelate a specific solvent or not. The process of self-assembly, in molecular gels, is intricate and must balance parameters influencing solubility and those contrasting forces that govern epitaxial growth into axially symmetric elongated aggregates. Although the gelator-gelator interactions are of paramount importance in understanding gelation, the solvent-gelator specific (i.e., H-bonding) and nonspecific (dipole-dipole, dipole-induced and instantaneous dipole induced forces) intermolecular interactions are equally important. Solvent properties mediate the self-assembly of molecular gelators into their self-assembled fibrillar networks. Herein, solubility parameters of solvents, ranging from partition coefficients (logP), to Henry's law constants (HLC), to solvatochromic ET(30) parameters, to Kamlet-Taft parameters (beta, alpha and pi), to Hansen solubility parameters (deltap, deltad, deltah), etc., are correlated with the gelation ability of numerous classes of molecular gelators. Advanced solvent clustering techniques have led to the development of a priori tools that can identify the solvents that will be gelled and not gelled by molecular gelators. These tools will greatly aid in the development of novel gelators without solely relying on serendipitous discoveries.

  6. REVIEW OF MOODLE PLUGINS FOR DESIGNING MULTIMEDIA ELECTRONIC EDUCATIONAL RESOURCES FROM LANGUAGE DISCIPLINES

    Directory of Open Access Journals (Sweden)

    Anton M. Avramchuk

    2015-09-01

    Full Text Available Today the problem of designing multimedia electronic educational resources from language disciplines in Moodle is very important. This system has a lot of different, powerful resources, plugins to facilitate the learning of students with language disciplines. This article presents an overview and comparative analysis of the five Moodle plugins for designing multimedia electronic educational resources from language disciplines. There have been considered their key features and functionality in order to choose the best for studying language disciplines in the Moodle. Plugins are compared by a group of experts according to the criteria: efficiency, functionality and easy use. For a comparative analysis of the plugins it is used the analytic hierarchy process.

  7. Effects of the Use of Electronic Human Resource Management (EHRM Within Human Resource Management (HRM Functions at Universities

    Directory of Open Access Journals (Sweden)

    Chux Gervase Iwu

    2016-09-01

    Full Text Available This study set out to examine the effect of e-hrm systems in assisting human resource practitioners to execute their duties and responsibilities. In comparison to developed economies of the world, information technology adoption in sub-Saharan Africa has not been without certain glitches. Some of the factors that are responsible for these include poor need identification, sustainable funding, and insufficient skills. Besides these factors, there is also the issue of change management and users sticking to what they already know. Although, the above factors seem negative, there is strong evidence that information systems such as electronic human resource management present benefits to an organization. To achieve this, a dual research approach was utilized. Literature assisted immensely in both the development of the conceptual framework upon which the study hinged as well as in the development of the questionnaire items. The study also made use of an interview checklist to guide the participants. The findings reveal a mix of responses that indicate that while there are gains in adopting e-hrm systems, it is wiser to consider supporting resources as well as articulate the needs of the university better before any investment is made.

  8. Oxidative enzymatic gelation of sugar beet pectin for emulsion stabilization

    DEFF Research Database (Denmark)

    Abang Zaidel, Dayang Norulfairuz; Meyer, Anne S.

    2013-01-01

    Pectin from sugar beet is derived from the sugar beet pulp residue which results when sugar beets are processed for sucrose extraction. The sugar beet pectin has poor gelationability by the classic divalentcation molecular mechanism because of a relatively high acetylation degree and short...... polygalacturonate backbone chain length. However, due to the feruloyl-substitutions on the side chains, the sugar beet pectic polysaccharides can be cross-linked via enzyme catalyzed oxidation. The enzyme kinetics and functionality of such oxidativelycross-linked sugar beet pectin, in relation to stabilizing...... emulsions has recently been investigated in model food emulsions. This paper reviews the pectin chemistry, enzymatic oxidative gelation mechanisms, interaction mechanisms of the sugar beet pectin with the emulsion droplets and explores how the gelation affects the rheology and stability of emulsion systems...

  9. Gelation of mucin: Protecting the stomach from autodigestion

    Science.gov (United States)

    Bansil, Rama

    2011-03-01

    In this talk I will describe the molecular mechanisms involved in the remarkable ability of the mucus lining of the stomach for protecting the stomach from being digested by the acidic gastric juices that it secretes. These physical properties can be attributed to the presence of a high molecular weight glycoprotein found in mucus, called mucin. Rheology and other measurements show that gastric mucin forms a gel under acidic pH. A model of gelation based on the interplay of hydrophobic and electrostatic interactions will be discussed. Molecular Dynamics simulation studies of folding and aggregation of mucin domains provide further support for this model. The relevance of gelation to the motion of the ulcer causing bacterium H. pylori will be discussed.

  10. The Electron Microscopy Outreach Program: A Web-based resource for research and education.

    Science.gov (United States)

    Sosinsky, G E; Baker, T S; Hand, G; Ellisman, M H

    1999-01-01

    We have developed a centralized World Wide Web (WWW)-based environment that serves as a resource of software tools and expertise for biological electron microscopy. A major focus is molecular electron microscopy, but the site also includes information and links on structural biology at all levels of resolution. This site serves to help integrate or link structural biology techniques in accordance with user needs. The WWW site, called the Electron Microscopy (EM) Outreach Program (URL: http://emoutreach.sdsc.edu), provides scientists with computational and educational tools for their research and edification. In particular, we have set up a centralized resource containing course notes, references, and links to image analysis and three-dimensional reconstruction software for investigators wanting to learn about EM techniques either within or outside of their fields of expertise. Copyright 1999 Academic Press.

  11. Identifying and evaluating electronic learning resources for use in adult-gerontology nurse practitioner education.

    Science.gov (United States)

    Thompson, Hilaire J; Belza, Basia; Baker, Margaret; Christianson, Phyllis; Doorenbos, Ardith; Nguyen, Huong

    2014-01-01

    Enhancing existing curricula to meet newly published adult-gerontology advanced practice registered nurse (APRN) competencies in an efficient manner presents a challenge to nurse educators. Incorporating shared, published electronic learning resources (ELRs) in existing or new courses may be appropriate in order to assist students in achieving competencies. The purposes of this project were to (a) identify relevant available ELR for use in enhancing geriatric APRN education and (b) to evaluate the educational utility of identified ELRs based on established criteria. A multilevel search strategy was used. Two independent team members reviewed identified ELR against established criteria to ensure utility. Only resources meeting all criteria were retained. Resources were found for each of the competency areas and included formats such as podcasts, Web casts, case studies, and teaching videos. In many cases, resources were identified using supplemental strategies and not through traditional search or search of existing geriatric repositories. Resources identified have been useful to advanced practice educators in improving lecture and seminar content in a particular topic area and providing students and preceptors with additional self-learning resources. Addressing sustainability within geriatric APRN education is critical for sharing of best practices among educators and for sustainability of teaching and related resources. © 2014.

  12. USE OF ELECTRONIC EDUCATIONAL RESOURCES WHEN TRAINING IN WORK WITH SPREADSHEETS

    Directory of Open Access Journals (Sweden)

    Х А Гербеков

    2017-12-01

    Full Text Available Today the tools for maintaining training courses based on opportunities of information and communication technologies are developed. Practically in all directions of preparation and on all subject matters electronic textbook and self-instruction manuals are created. Nevertheless the industry of computer educational and methodical materials actively develops and gets more and more areas of development and introduction. In this regard more and more urgent is a problem of development of the electronic educational resources adequate to modern educational requirements. Creation and the organization of training courses with use of electronic educational resources in particular on the basis of Internet technologies remains a difficult methodical task.In article the questions connected with development of electronic educational resources for use when studying the substantial line “Information technologies” of a school course of informatics in particular for studying of spreadsheets are considered. Also the analysis of maintenance of a school course and the unified state examination from the point of view of representation of task in him corresponding to the substantial line of studying “Information technologies” on mastering technology of information processing in spreadsheets and the methods of visualization given by means of charts and schedules is carried out.

  13. Chiral bis(amino acid)- and bis(amino alcohol)-oxalamide gelators. Gelation properties, self-assembly motifs and chirality effects.

    Science.gov (United States)

    Frkanec, Leo; Zinić, Mladen

    2010-01-28

    Bis(amino acid)- and bis(amino alcohol)oxalamide gelators represent the class of versatile gelators whose gelation ability is a consequence of strong and directional intermolecular hydrogen bonding provided by oxalamide units and lack of molecular symmetry due to the presence of two chiral centres. Bis(amino acid)oxalamides exhibit ambidextrous gelation properties, being capable to form gels with apolar and also highly polar solvent systems and tend to organise into bilayers or inverse bilayers in hydrogel or organic solvent gel assemblies, respectively. (1)H NMR and FTIR studies of gels revealed the importance of the equilibrium between the assembled network and smaller dissolved gelator assemblies. The organisation in gel assemblies deduced from spectroscopic structural studies are in certain cases closely related to organisations found in the crystal structures of selected gelators, confirming similar organisations in gel assemblies and in the solid state. The pure enantiomer/racemate gelation controversy is addressed and the evidence provided that rac-16 forms a stable toluene gel due to resolution into enantiomeric bilayers, which then interact giving gel fibres and a network of different morphology compared to its (S,S)-enantiomer gel. The TEM investigation of both gels confirmed distinctly different gel morphologies, which allowed the relationship between the stereochemical form of the gelator, the fibre and the network morphology and the network solvent immobilisation capacity to be proposed. Mixing of the constitutionally different bis(amino acid) and bis(amino alcohol)oxalamide gelators resulted in some cases in highly improved gelation efficiency denoted as synergic gelation effect (SGE), being highly dependent also on the stereochemistry of the component gelators. Examples of photo-induced gelation based on closely related bis(amino acid)-maleic acid amide and -fumaramide and stilbene derived oxalamides where gels form by irradiation of the solution of

  14. From Millennium ERM to Proquest 360 Resource Manager: Implementing a new Electronic Resources Management System ERMS in an International Graduate Research University in Saudi Arabia

    KAUST Repository

    Ramli, Rindra M.

    2017-01-01

    An overview of the Recommendation Study and the subsequent Implementation of a new Electronic Resources Management system ERMS in an international graduate research university in the Kingdom of Saudi Arabia. It covers the timeline, deliverables

  15. Availability, Level of Use and Constraints to Use of Electronic Resources by Law Lecturers in Public Universities in Nigeria

    Science.gov (United States)

    Amusa, Oyintola Isiaka; Atinmo, Morayo

    2016-01-01

    (Purpose) This study surveyed the level of availability, use and constraints to use of electronic resources among law lecturers in Nigeria. (Methodology) Five hundred and fifty-two law lecturers were surveyed and four hundred and forty-two responded. (Results) Data analysis revealed that the level of availability of electronic resources for the…

  16. GUIDELINES FOR EVALUATION OF PSYCHOLOGICAL AND PEDAGOGICAL QUALITY CHARACTERISTICS OF ELECTRONIC EDUCATIONAL RESOURCES

    Directory of Open Access Journals (Sweden)

    Galina P. Lavrentieva

    2014-05-01

    Full Text Available The article highlights the causes of insufficient effective use of electronic learning resources and sets out the guidelines on ways to solve the aforementioned problems. The set of didactic, methodical, psychological, pedagogical, design and ergonomic quality requirements is considered for evaluation, selection and application of information and communication technologies in the educational process. The most appropriate mechanisms for the ICT introduction into the learning process are disclosed as it should meet the specific learning needs of the student and the objectives of the educational process. The guidance for psycho-educational assessment of quality of electronic educational resources is provided. It is argued that the effectiveness of the ICT use is to be improved by means of quality evaluation mechanisms involved into the educational process.

  17. Model of e-learning with electronic educational resources of new generation

    OpenAIRE

    A. V. Loban; D. A. Lovtsov

    2017-01-01

    Purpose of the article: improving of scientific and methodical base of the theory of the е-learning of variability. Methods used: conceptual and logical modeling of the е-learning of variability process with electronic educational resource of new generation and system analysis of the interconnection of the studied subject area, methods, didactics approaches and information and communication technologies means. Results: the formalization complex model of the е-learning of variability with elec...

  18. A systematic review of portable electronic technology for health education in resource-limited settings.

    Science.gov (United States)

    McHenry, Megan S; Fischer, Lydia J; Chun, Yeona; Vreeman, Rachel C

    2017-08-01

    The objective of this study is to conduct a systematic review of the literature of how portable electronic technologies with offline functionality are perceived and used to provide health education in resource-limited settings. Three reviewers evaluated articles and performed a bibliography search to identify studies describing health education delivered by portable electronic device with offline functionality in low- or middle-income countries. Data extracted included: study population; study design and type of analysis; type of technology used; method of use; setting of technology use; impact on caregivers, patients, or overall health outcomes; and reported limitations. Searches yielded 5514 unique titles. Out of 75 critically reviewed full-text articles, 10 met inclusion criteria. Study locations included Botswana, Peru, Kenya, Thailand, Nigeria, India, Ghana, and Tanzania. Topics addressed included: development of healthcare worker training modules, clinical decision support tools, patient education tools, perceptions and usability of portable electronic technology, and comparisons of technologies and/or mobile applications. Studies primarily looked at the assessment of developed educational modules on trainee health knowledge, perceptions and usability of technology, and comparisons of technologies. Overall, studies reported positive results for portable electronic device-based health education, frequently reporting increased provider/patient knowledge, improved patient outcomes in both quality of care and management, increased provider comfort level with technology, and an environment characterized by increased levels of technology-based, informal learning situations. Negative assessments included high investment costs, lack of technical support, and fear of device theft. While the research is limited, portable electronic educational resources present promising avenues to increase access to effective health education in resource-limited settings, contingent

  19. Selective removals of heavy metals (Pb(2+), Cu(2+), and Cd(2+)) from wastewater by gelation with alginate for effective metal recovery.

    Science.gov (United States)

    Wang, Fei; Lu, Xingwen; Li, Xiao-yan

    2016-05-05

    A novel method that uses the aqueous sodium alginate solution for direct gelation with metal ions is developed for effective removal and recovery of heavy metals from industrial wastewater. The experimental study was conducted on Pb(2+), Cu(2+), and Cd(2+) as the model heavy metals. The results show that gels can be formed rapidly between the metals and alginate in less than 10 min and the gelation rates fit well with the pseudo second-order kinetic model. The optimum dosing ratio of alginate to the metal ions was found to be between 2:1 and 3:1 for removing Pb(2+) and around 4:1 for removing Cu(2+) and Cd(2+) from wastewater, and the metal removal efficiency by gelation increased as the solution pH increased. Alginate exhibited a higher gelation affinity toward Pb(2+) than Cu(2+) and Cd(2+), which allowed a selective removal of Pb(2+) from the wastewater in the presence of Cu(2+) and Cd(2+) ions. Chemical analysis of the gels suggests that the gelation mainly occurred between the metal ions and the -COO(-) and -OH groups on alginate. By simple calcination of the metal-laden gels at 700 °C for 1 h, the heavy metals can be well recovered as valuable resources. The metals obtained after the thermal treatment are in the form of PbO, CuO, and CdO nanopowders with crystal sizes of around 150, 50, and 100 nm, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

  20. Model of e-learning with electronic educational resources of new generation

    Directory of Open Access Journals (Sweden)

    A. V. Loban

    2017-01-01

    Full Text Available Purpose of the article: improving of scientific and methodical base of the theory of the е-learning of variability. Methods used: conceptual and logical modeling of the е-learning of variability process with electronic educational resource of new generation and system analysis of the interconnection of the studied subject area, methods, didactics approaches and information and communication technologies means. Results: the formalization complex model of the е-learning of variability with electronic educational resource of new generation is developed, conditionally decomposed into three basic components: the formalization model of the course in the form of the thesaurusclassifier (“Author of e-resource”, the model of learning as management (“Coordination. Consultation. Control”, the learning model with the thesaurus-classifier (“Student”. Model “Author of e-resource” allows the student to achieve completeness, high degree of didactic elaboration and structuring of the studied material in triples of variants: modules of education information, practical task and control tasks; the result of the student’s (author’s of e-resource activity is the thesaurus-classifier. Model of learning as management is based on the principle of personal orientation of learning in computer environment and determines the logic of interaction between the lecturer and the student when determining the triple of variants individually for each student; organization of a dialogue between the lecturer and the student for consulting purposes; personal control of the student’s success (report generation and iterative search for the concept of the class assignment in the thesaurus-classifier before acquiring the required level of training. Model “Student” makes it possible to concretize the learning tasks in relation to the personality of the student and to the training level achieved; the assumption of the lecturer about the level of training of a

  1. Preparation of porous zirconia microspheres by internal gelation method

    International Nuclear Information System (INIS)

    Pathak, Sachin S.; Pius, I.C.; Bhanushali, R.D.; Rao, T.V. Vittal; Mukerjee, S.K.

    2008-01-01

    A modified internal gelation process for the preparation of porous zirconia microspheres has been developed. The conventional method has been modified by adding a surfactant in the feed broth. The effects of variation of surfactant concentration, washing techniques and temperature of calcination on the pore volume and the surface area of the microspheres have been studied. The conditions were optimized to obtain porous stable microspheres suitable for various applications. The microspheres were characterized by surface area analysis, pore volume analysis, thermogravimetric analysis and X-ray diffraction. The ion exchange behavior was studied using pH titration

  2. Gelation of covalently edge-modified laponites in aqueous media. 1. rheology and nuclear magnetic resonance.

    Science.gov (United States)

    Patil, Suhas P; Mathew, Renny; Ajithkumar, T G; Rajamohanan, P R; Mahesh, T S; Kumaraswamy, Guruswamy

    2008-04-17

    We describe the covalent modification of the edges of laponite with organic groups and the influence of this modification on gelation behavior. We compare three materials: an unmodified laponite, a laponite edge modified with a trimethyl moiety (MLap), and an octyldimethyl moiety (OLap). Gelation is investigated using rheology and NMR T1 relaxation measurements and nuclear Overhauser enhancement spectroscopy (NOESY). MLap and OLap show qualitatively different gelation. Gelation of MLap is very similar to laponite: MLap gels over the same time scale as laponite and has about the same solid modulus, and the MLap gel is almost as transparent as laponite. In contrast, OLap gels rapidly relative to laponite and forms a weak, turbid gel. We believe that gelation in laponite and MLap results from the formation of a network of well-dispersed platelets (or a few platelets), while in OLap, gelation results from a network of stacks of several platelets. NMR relaxation measurements indicate that gelation does not affect the average relaxation of water protons. However, T1 increases marginally for the protons in the organic moieties in MLap and decreases for protons in the organic moieties in OLap. Relaxation measurements, analyses of line width, and NOESY taken together suggest that, in OLap, gelation is a consequence of association of the organic moieties on the laponite edges, and that this association strengthens with time. Thus, the time-dependent changes in NMR suggest a structural origin for the time-dependent changes in the rheological behavior.

  3. Towards a fragment-based approach in gelator design: halogen effects leading to thixotropic, mouldable and self-healing systems in aryl-triazolyl amino acid-based gelators!

    Science.gov (United States)

    Srivastava, Bhartendu K; Manheri, Muraleedharan K

    2017-04-18

    A simple replacement of a H atom by Br transformed non-gelating aryl triazolyl amino acid benzyl ester into a versatile gelator, which formed shape-persistent, self-healing and mouldable gels. The 'bromo-aryl benzyl ester' fragment was then transplanted into another framework, which resulted in similar solvent preference and gelation efficiency.

  4. Review of material recovery from used electric and electronic equipment-alternative options for resource conservation.

    Science.gov (United States)

    Friege, Henning

    2012-09-01

    For waste from electric and electronic equipment, the WEEE Directive stipulates the separate collection of electric and electronic waste. As to new electric and electronic devices, the Restriction of Hazardous Substances (RoHS) Directive bans the use of certain chemicals dangerous for man and environment. From the implementation of the WEEE directive, many unsolved problems have been documented: poor collection success, emission of dangerous substances during collection and recycling, irretrievable loss of valuable metals among others. As to RoHS, data from the literature show a satisfying success. The problems identified in the process can be reduced to some basic dilemmas at the borders between waste management, product policy and chemical safety. The objectives of the WEEE Directive and the specific targets for use and recycling of appliances are not consistent. There is no focus on scarce resources. Extended producer responsibility is not sufficient to guarantee sustainable waste management. Waste management reaches its limits due to problems of implementation but also due to physical laws. A holistic approach is necessary looking at all branch points and sinks in the stream of used products and waste from electric and electronic equipment. This may be done with respect to the general rules for sustainable management of material streams covering the three dimensions of sustainable policy. The relationships between the players in the field of electric and electronic devices have to be taken into account. Most of the problems identified in the implementation process will not be solved by the current amendment of the WEEE Directive.

  5. [Use of internet and electronic resources among Spanish intensivist physicians. First national survey].

    Science.gov (United States)

    Gómez-Tello, V; Latour-Pérez, J; Añón Elizalde, J M; Palencia-Herrejón, E; Díaz-Alersi, R; De Lucas-García, N

    2006-01-01

    Estimate knowledge and use habits of different electronic resources in a sample of Spanish intensivists: Internet, E-mail, distribution lists, and use of portable electronic devices. Self-applied questionnaire. A 50-question questionnaire was distributed among Spanish intensivists through the hospital marketing delegates of a pharmaceutical company and of electronic forums. A total of 682 questionnaires were analyzed (participation: 74%). Ninety six percent of those surveyed used Internet individually: 67% admitted training gap. Internet was the second source of clinical consultations most used (61%), slightly behind consultation to colleagues (65%). The pages consulted most were bibliographic databases (65%) and electronic professional journals (63%), with limited use of Evidence Based Medicine pages (19%). Ninety percent of those surveyed used e-mail regularly in the practice of their profession, although 25% admitted that were not aware of its possibilities. The use of E-mail decreased significantly with increase in age. A total of 62% of the intensivists used distribution lists. Of the rest, 42% were not aware of its existence and 32% admitted they had insufficient training to handle them. Twenty percent of those surveyed had portable electronic devices and 64% considered it useful, basically due to its rapid consultation at bedside. Female gender was a negative predictive factor of its use (OR 0.35; 95% CI 0.2-0.63; p=0.0002). A large majority of the Spanish intensivists use Internet and E-mail. E-mail lists and use of portable devices are still underused resources. There are important gaps in training and infrequent use of essential pages. There are specific groups that require directed educational policies.

  6. Stabilization of oil-in-water emulsions by enzyme catalyzed oxidative gelation of sugar beet pectin

    DEFF Research Database (Denmark)

    Abang Zaidel, Dayang Norulfairuz; Chronakis, Ioannis S.; Meyer, Anne S.

    2013-01-01

    Enzyme catalyzed oxidative cross-linking of feruloyl groups can promote gelation of sugar beet pectin (SBP). It is uncertain how the enzyme kinetics of this cross-linking reaction are affected in emulsion systems and whether the gelation affects emulsion stability. In this study, SBP (2.5% w...... larger average particle sizes than the emulsions in which the SBP was homogenized into the emulsion system during emulsion preparation (referred as Mix B). Mix B type emulsions were stable. Enzyme catalyzed oxidative gelation of SBP helped stabilize the emulsions in Mix A. The kinetics of the enzyme...... catalyzed oxidative gelation of SBP was evaluated by small angle oscillatory measurements for horseradish peroxidase (HRP) (EC 1.11.1.7) and laccase (EC 1.10.3.2) catalysis, respectively. HRP catalyzed gelation rates, determined from the slopes of the increase of elastic modulus (G0) with time, were higher...

  7. Effects of irradiation on the gelation properties of muscle protein

    International Nuclear Information System (INIS)

    Lin Xianping; Yang Wenge

    2014-01-01

    Gel properties of muscle protein are the important functional characteristics in meat and its products. which determine the meat products' unique quality. such as texture. Juiciness. fat content and sensory characteristics As a novel food preservation technique, irradiation may lead to changes in the composition and structure of protein molecule. and impact the gel forming ability and gelation properties of muscle protein. Based on the introduction of gel forming mechanism of muscle protein, effects of irradiation on the water holding capacity, mechanical properties and structure of muscle protein gel were reviewed in detail. High-dose irradiation could weaken the water holding capacity of muscle protein and result in the loss of meat juice. With different irradiation conditions or raw materials, influences of irradiation on the texture and theological properties of muscle protein gels are varied, and effects on the structure of muscle protein and its gel are more complex. Finally, the research trend of irradiation effects on the gelation properties of muscle protein is put forward. (authors)

  8. Solubility and dissolution improvement of ketoprofen by emulsification ionic gelation

    Science.gov (United States)

    Rachmaniar, Revika; Tristiyanti, Deby; Hamdani, Syarif; Afifah

    2018-02-01

    Ketoprofen or [2-(3-benzoylphenyl) propionic acid] is non-steroidal anti-inflammatory (NSAID) and an analgesic which has high permeability and low solubility. The purpose of this work was to improve the solubility and dissolution of poorly water-soluble ketoprofen prepared by emulsification ionic gelation method and utilizing polymer (chitosan) and cross linker (tripolyphosphate, TPP) for particles formulation. The results show that increasing pH value of TPP, higher solubility and dissolution of as-prepared ketoprofen-chitosan was obtained. The solubility in water of ketoprofen-chitosan with pH 6 for TPP increased 2.71-fold compared to untreated ketoprofen. While the dissolution of ketoprofen-chitosan with pH 6 of TPP in simulated gastric fluid without enzyme (0.1 N HCl), pH 4.5 buffer and simulated intestinal fluid without enzyme (phosphate buffer pH 6.8) was increased 1.9-fold, 1.6-fold and 1.2-fold compared to untreated ketoprofen for dissolution time of 30 minutes, respectively. It could be concluded that chitosan and TPP in the emulsification ionic gelation method for ketoprofen preparation effectively increases solubility and dissolution of poorly water-soluble ketoprofen.

  9. The Synthesis of the Hierarchical Structure of Information Resources for Management of Electronic Commerce Entities

    Directory of Open Access Journals (Sweden)

    Krutova Anzhelika S.

    2017-06-01

    Full Text Available The aim of the article is to develop the theoretical bases for the classification and coding of economic information and the scientific justification of the content of information resources of an electronic commerce enterprise. The essence of information resources for management of electronic business entities is investigated. It is proved that the organization of accounting in e-commerce systems is advisable to be built on the basis of two circuits: accounting for financial flows and accounting associated with transformation of business factors in products and services as a result of production activities. There presented a sequence of accounting organization that allows to combine the both circuits in a single information system, which provides a possibility for the integrated replenishment and distributed simultaneous use of the e-commerce system by all groups of users. It is proved that the guarantee of efficient activity of the information management system of electronic commerce entities is a proper systematization of the aggregate of information resources on economic facts and operations of an enterprise in accordance with the management tasks by building the hierarchy of accounting nomenclatures. It is suggested to understand nomenclature as an objective, primary information aggregate concerning a certain fact of the economic activity of an enterprise, which is characterized by minimum requisites, is entered into the database of the information system and is to be reflected in the accounting system. It is proposed to build a database of e-commerce systems as a part of directories (constants, personnel, goods / products, suppliers, buyers and the hierarchy of accounting nomenclatures. The package of documents regulating the organization of accounting at an enterprise should include: the provision on the accounting services, the order on the accounting policy, the job descriptions, the schedules of information exchange, the report card and

  10. ELECTRONIC EDUCATIONAL RESOURCES FOR ONLINE SUPPORT OF MODERN CHEMISTRY CLASSES IN SPECIALIZED SCHOOL

    Directory of Open Access Journals (Sweden)

    Maria D. Tukalo

    2013-09-01

    Full Text Available This article contains material of some modern electronic educational resources that can be used via the Internet to support the modern chemistry classes in specialized school. It was drawn attention to the educational chemical experiments as means of knowledge; simulated key motivational characteristics to enhance students interest for learning subjects, their cognitive and practical activity in the formation of self-reliance and self-creative; commented forecasts for creating of conditions to enhance the creative potential of students in a modern learning environment.

  11. THE MODEL OF LINGUISTIC TEACHERS’ COMPETENCY DEVELOPMENT ON DESIGNING MULTIMEDIA ELECTRONIC EDUCATIONAL RESOURCES IN THE MOODLE SYSTEM

    Directory of Open Access Journals (Sweden)

    Anton M. Avramchuk

    2017-10-01

    Full Text Available The article is devoted to the problem of developing the competency of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system. The concept of "the competence of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system" is justified and defined. Identified and characterized the components by which the levels of the competency development of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system should be assessed. Developed a model for the development of the competency of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system, which is based on the main scientific approaches, used in adult education, and consists of five blocks: target, informative, technological, diagnostic and effective.

  12. A preliminary categorization of end-of-life electrical and electronic equipment as secondary metal resources

    International Nuclear Information System (INIS)

    Oguchi, Masahiro; Murakami, Shinsuke; Sakanakura, Hirofumi; Kida, Akiko; Kameya, Takashi

    2011-01-01

    Highlights: → End-of-life electrical and electronic equipment (EEE) as secondary metal resources. → The content and the total amount of metals in specific equipment are both important. → We categorized 21 EEE types from contents and total amounts of various metals. → Important equipment types as secondary resources were listed for each metal kind. → Collectability and possible collection systems of various EEE types were discussed. - Abstract: End-of-life electrical and electronic equipment (EEE) has recently received attention as a secondary source of metals. This study examined characteristics of end-of-life EEE as secondary metal resources to consider efficient collection and metal recovery systems according to the specific metals and types of EEE. We constructed an analogy between natural resource development and metal recovery from end-of-life EEE and found that metal content and total annual amount of metal contained in each type of end-of-life EEE should be considered in secondary resource development, as well as the collectability of the end-of-life products. We then categorized 21 EEE types into five groups and discussed their potential as secondary metal resources. Refrigerators, washing machines, air conditioners, and CRT TVs were evaluated as the most important sources of common metals, and personal computers, mobile phones, and video games were evaluated as the most important sources of precious metals. Several types of small digital equipment were also identified as important sources of precious metals; however, mid-size information and communication technology (ICT) equipment (e.g., printers and fax machines) and audio/video equipment were shown to be more important as a source of a variety of less common metals. The physical collectability of each type of EEE was roughly characterized by unit size and number of end-of-life products generated annually. Current collection systems in Japan were examined and potentially appropriate collection

  13. Open-Source Electronic Health Record Systems for Low-Resource Settings: Systematic Review.

    Science.gov (United States)

    Syzdykova, Assel; Malta, André; Zolfo, Maria; Diro, Ermias; Oliveira, José Luis

    2017-11-13

    Despite the great impact of information and communication technologies on clinical practice and on the quality of health services, this trend has been almost exclusive to developed countries, whereas countries with poor resources suffer from many economic and social issues that have hindered the real benefits of electronic health (eHealth) tools. As a component of eHealth systems, electronic health records (EHRs) play a fundamental role in patient management and effective medical care services. Thus, the adoption of EHRs in regions with a lack of infrastructure, untrained staff, and ill-equipped health care providers is an important task. However, the main barrier to adopting EHR software in low- and middle-income countries is the cost of its purchase and maintenance, which highlights the open-source approach as a good solution for these underserved areas. The aim of this study was to conduct a systematic review of open-source EHR systems based on the requirements and limitations of low-resource settings. First, we reviewed existing literature on the comparison of available open-source solutions. In close collaboration with the University of Gondar Hospital, Ethiopia, we identified common limitations in poor resource environments and also the main requirements that EHRs should support. Then, we extensively evaluated the current open-source EHR solutions, discussing their strengths and weaknesses, and their appropriateness to fulfill a predefined set of features relevant for low-resource settings. The evaluation methodology allowed assessment of several key aspects of available solutions that are as follows: (1) integrated applications, (2) configurable reports, (3) custom reports, (4) custom forms, (5) interoperability, (6) coding systems, (7) authentication methods, (8) patient portal, (9) access control model, (10) cryptographic features, (11) flexible data model, (12) offline support, (13) native client, (14) Web client,(15) other clients, (16) code

  14. THE MODEL OF LINGUISTIC TEACHERS’ COMPETENCY DEVELOPMENT ON DESIGNING MULTIMEDIA ELECTRONIC EDUCATIONAL RESOURCES IN THE MOODLE SYSTEM

    OpenAIRE

    Anton M. Avramchuk

    2017-01-01

    The article is devoted to the problem of developing the competency of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system. The concept of "the competence of teachers of language disciplines on designing multimedia electronic educational resources in the Moodle system" is justified and defined. Identified and characterized the components by which the levels of the competency development of teachers of language disciplines on designing ...

  15. Determining the level of awareness of the physicians in using the variety of electronic information resources and the effecting factors.

    Science.gov (United States)

    Papi, Ahmad; Ghazavi, Roghayeh; Moradi, Salimeh

    2015-01-01

    Understanding of the medical society's from the types of information resources for quick and easy access to information is an imperative task in medical researches and management of the treatment. The present study was aimed to determine the level of awareness of the physicians in using various electronic information resources and the factors affecting it. This study was a descriptive survey. The data collection tool was a researcher-made questionnaire. The study population included all the physicians and specialty physicians of the teaching hospitals affiliated to Isfahan University of Medical Sciences and numbered 350. The sample size based on Morgan's formula was set at 180. The content validity of the tool was confirmed by the library and information professionals and the reliability was 95%. Descriptive statistics were used including the SPSS software version 19. On reviewing the need of the physicians to obtain the information on several occasions, the need for information in conducting the researches was reported by the maximum number of physicians (91.9%) and the usage of information resources, especially the electronic resources, formed 65.4% as the highest rate with regard to meeting the information needs of the physicians. Among the electronic information databases, the maximum awareness was related to Medline with 86.5%. Among the various electronic information resources, the highest awareness (43.3%) was related to the E-journals. The highest usage (36%) was also from the same source. The studied physicians considered the most effective deterrent in the use of electronic information resources as being too busy and lack of time. Despite the importance of electronic information resources for the physician's community, there was no comprehensive knowledge of these resources. This can lead to less usage of these resources. Therefore, careful planning is necessary in the hospital libraries in order to introduce the facilities and full capabilities of the

  16. Success criteria for electronic medical record implementations in low-resource settings: a systematic review.

    Science.gov (United States)

    Fritz, Fleur; Tilahun, Binyam; Dugas, Martin

    2015-03-01

    Electronic medical record (EMR) systems have the potential of supporting clinical work by providing the right information at the right time to the right people and thus make efficient use of resources. This is especially important in low-resource settings where reliable data are also needed to support public health and local supporting organizations. In this systematic literature review, our objectives are to identify and collect literature about success criteria of EMR implementations in low-resource settings and to summarize them into recommendations. Our search strategy relied on PubMed queries and manual bibliography reviews. Studies were included if EMR implementations in low-resource settings were described. The extracted success criteria and measurements were summarized into 7 categories: ethical, financial, functionality, organizational, political, technical, and training. We collected 381 success criteria with 229 measurements from 47 articles out of 223 articles. Most papers were evaluations or lessons learned from African countries, published from 1999 to 2013. Almost half of the EMR systems served a specific disease area like human immunodeficiency virus (HIV). The majority of criteria that were reported dealt with the functionality, followed by organizational issues, and technical infrastructures. Sufficient training and skilled personnel were mentioned in roughly 10%. Political, ethical, and financial considerations did not play a predominant role. More evaluations based on reliable frameworks are needed. Highly reliable data handling methods, human resources and effective project management, as well as technical architecture and infrastructure are all key factors for successful EMR implementation. © The Author 2015. Published by Oxford University Press on behalf of the American Medical Informatics Association. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Impact of Knowledge Resources Linked to an Electronic Health Record on Frequency of Unnecessary Tests and Treatments

    Science.gov (United States)

    Goodman, Kenneth; Grad, Roland; Pluye, Pierre; Nowacki, Amy; Hickner, John

    2012-01-01

    Introduction: Electronic knowledge resources have the potential to rapidly provide answers to clinicians' questions. We sought to determine clinicians' reasons for searching these resources, the rate of finding relevant information, and the perceived clinical impact of the information they retrieved. Methods: We asked general internists, family…

  18. Resource conservation approached with an appropriate collection and upgrade-remanufacturing for used electronic products.

    Science.gov (United States)

    Zlamparet, Gabriel I; Tan, Quanyin; Stevels, A B; Li, Jinhui

    2018-03-01

    This comparative research represents an example for a better conservation of resources by reducing the amount of waste (kg) and providing it more value under the umbrella of remanufacturing. The three discussed cases will expose three issues already addressed separately in the literature. The generation of waste electrical and electronic equipment (WEEE) interacts with the environmental depletion. In this article, we gave the examples of addressed issues under the concept of remanufacturing. Online collection opportunity eliminating classical collection, a business to business (B2B) implementation for remanufactured servers and medical devices. The material reuse (recycling), component sustainability, reuse (part harvesting), product reuse (after repair/remanufacturing) indicates the recovery potential using remanufacturing tool for a better conservation of resources adding more value to the products. Our findings can provide an overview of new system organization for the general collection, market potential and the technological advantages using remanufacturing instead of recycling of WEEE or used electrical and electronic equipment. Copyright © 2017. Published by Elsevier Ltd.

  19. Studying the gelation process of titanium isopropoxide by method of positron annihilation spectroscopy; Studium procesu gelacie izopropoxidu titaniciteho metodou pozitronovej anihilacnej spektroskopie

    Energy Technology Data Exchange (ETDEWEB)

    Nyblova, D.; Jesenak, K. [Univerzita Komenskeho, Prirodovedecka fakulta, Katedra anorganickej chemie, 84215 Bratislava (Slovakia); Sausa, O. [Slovenska akademia vied, Fyzikalny ustav, 84511 Bratislava (Slovakia)

    2013-04-16

    Thank to its harmlessness titanium dioxide is widely utilized material. One of the new areas to use titanium dioxide is photocatalysis, which could be the way to e.g. remove organic pollutants from water or air. Titanium dioxide based gels are perspective form of TiO{sub 2} for photocatalysis because of their high porosity thus high surface area. Positron annihilation spectroscopy is a physical method to study microporous structure and electron energy distribution in materials. We studied gelation process of titanium isopropoxide in ethanol with various amount of water catalyzed by hydrochloric acid by positron annihilation lifetime spectroscopy and doppler broadening of annihilation line in this work. Positronium is weakly formed in TiO{sub 2} in general wherefore it cannot be monitored by positron annihilation spectroscopy very well. Gelation process can be monitored through pick-off annihilation of ortho-positronium. (authors)

  20. Gelation or molecular recognition; is the bis-(α,β-dihydroxy esters motif an omnigelator?

    Directory of Open Access Journals (Sweden)

    Peter C. Griffiths

    2010-11-01

    Full Text Available Understanding the gelation of liquids by low molecular weight solutes at low concentrations gives an insight into many molecular recognition phenomena and also offers a simple route to modifying the physical properties of the liquid. Bis-(α,β-dihydroxy esters are shown here to gel thermoreversibly a wide range of solvents, raising interesting questions as to the mechanism of gelation. At gelator concentrations of 5–50 mg ml−1, gels were successfully formed in acetone, ethanol/water mixtures, toluene, cyclohexane and chloroform (the latter, albeit at a higher gelator concentration. A range of neutron techniques – in particular small-angle neutron scattering (SANS – have been employed to probe the structure of a selection of these gels. The universality of gelation in a range of solvent types suggests the gelation mechanism is a feature of the bis-(α,β-dihydroxy ester motif, with SANS demonstrating the presence of regular structures in the 30–40 Å range. A correlation between the apparent rodlike character of the structures formed and the polarity of the solvent is evident. Preliminary spin-echo neutron scattering studies (SESANS indicated the absence of any larger scale structures. Inelastic neutron spectroscopy (INS studies demonstrated that the solvent is largely unaffected by gelation, but does reveal insights into the thermal history of the samples. Further neutron studies of this kind (particularly SESANS and INS are warranted, and it is hoped that this work will stimulate others to pursue this line of research.

  1. Electronic theses and dissertations: a review of this valuable resource for nurse scholars worldwide.

    Science.gov (United States)

    Goodfellow, L M

    2009-06-01

    A worldwide repository of electronic theses and dissertations (ETDs) could provide worldwide access to the most up-to-date research generated by masters and doctoral students. Until that international repository is established, it is possible to access some of these valuable knowledge resources. ETDs provide a technologically advanced medium with endless multimedia capabilities that far exceed the print and bound copies of theses and dissertations housed traditionally in individual university libraries. CURRENT USE: A growing trend exists for universities worldwide to require graduate students to submit theses or dissertations as electronic documents. However, nurse scholars underutilize ETDs, as evidenced by perusing bibliographic citation lists in many of the research journals. ETDs can be searched for and retrieved through several digital resources such as the Networked Digital Library of Theses and Dissertations (http://www.ndltd.org), ProQuest Dissertations and Theses (http://www.umi.com), the Australasian Digital Theses Program (http://adt.caul.edu.au/) and through individual university web sites and online catalogues. An international repository of ETDs benefits the community of nurse scholars in many ways. The ability to access recent graduate students' research electronically from anywhere in the world is advantageous. For scholars residing in developing countries, access to these ETDs may prove to be even more valuable. In some cases, ETDs are not available for worldwide access and can only be accessed through the university library from which the student graduated. Public access to university library ETD collections is not always permitted. Nurse scholars from both developing and developed countries could benefit from ETDs.

  2. Enzymatic gelation of sugar beet pectin in food products

    DEFF Research Database (Denmark)

    Bergsøe, Merete Norsker; Jensen, Mette; Adler-Nissen, Jens

    2000-01-01

    Sugar beet pectin is a food ingredient with specific functional properties. It may form gels by an oxidative cross-linking of ferulic acid. In the present study, the gel forming properties of three oxidative enzymes were examined in different food relevant conditions. The enzymes chosen were two...... laccases and one peroxidase. The textural properties of the produced gels were measured on a texture analyser. The influence of sugar, salt and protein were analysed. Finally, the enzymatic gelation was studied in three food products with added sugar beet pectin. These were black currant juice, milk...... and chopped heat-treated meat emulsion. The addition of salt resulted in softer, less stiff and chewy, and less adhesive gels. Generally speaking, sugar addition increased the hardness but at high concentration the gels were very brittle. However, Young's modulus was lower in gels containing sugar than...

  3. Study of the gelation behaviour of Brazilian waxy crude oils

    Energy Technology Data Exchange (ETDEWEB)

    Ziglio, C.M.; Sant' Ana, D.F. [Petroleo Brasileiro S.A., Petrobras, Rio de Janeiro (Brazil)

    2008-07-01

    The precipitation of wax from crude oil results in the formation of a paraffin network which evolves into a gel structure, causing a major operating issue for the petroleum industry. A gelled oil in a pipeline may need a very high re-start pressure that is beyond the capacity of the pump. The gelation of the oil can also develop into a wax deposit on the pipeline wall that restricts the flow of crude oil. Rheometry tests were used in this study to determine the yielding process of wax gels formed by the cooling of Brazilian crude oils. The effect of selected chemical additives on the gel strength was also examined. Dynamic rheology was used to study the oil-gel transition under quiescent conditions. Two rheological methods were used to study the gel yield stress, which is related to the gel strength. In the Creep and Recovery method, a stress was applied to the sample for a short period while the resulting deformation was measured. The stress was then removed to allow the sample to recover the gel structure. The steps of creep and recovery were repeated with an increasing stress value. The yield stress was identified as the minimum stress to cause an irreversible deformation in the sample. The yield stress of the gelled oil was estimated through dynamic measurements. Gel breakdown occurred when the sample was submitted to a critical strain, which is related to the yield stress value. This study showed that the gelation temperature can be reduced considerably by adding small amounts of readily available additives. These additives have an influence on yield stress values. In a cold re-start situation, they can reduce the pump pressure.

  4. From Millennium ERM to Proquest 360 Resource Manager: Implementing a new Electronic Resources Management System ERMS in an International Graduate Research University in Saudi Arabia

    KAUST Repository

    Ramli, Rindra M.

    2017-05-17

    An overview of the Recommendation Study and the subsequent Implementation of a new Electronic Resources Management system ERMS in an international graduate research university in the Kingdom of Saudi Arabia. It covers the timeline, deliverables and challenges as well as lessons learnt by the Project Team.

  5. Effect of gum tragacanth exuded by three Iranian Astragalus on mixed milk protein system during acid gelation.

    Science.gov (United States)

    Nejatian, Mohammad; Hatami, Masoud; Mohammadifar, Mohammad Amin

    2013-02-01

    The effects of various concentrations of three species of gum tragacanth on the gelation process, microstructure and viscoelastic properties of milk protein mixed gels acidified at 37°C by glucono-δ-lactone (GDL) were investigated using dynamic rheometry and microscopy. According to rheological measurements, the addition of gum tragacanth in the range of 0.05-0.2% (w/w) into milk protein dispersions led to a weaker structure for the milk protein network, compared to the control sample. This weakening effect could be eliminated by adding 0.3% (w/w) gum tragacanth exudates from A. gossypinus; the compositional features of gum tragacanth may have been responsible for the improved protein-protein interactions, greater structural strength and reduced gelation time onset. It was determined by scanning electron microscopy that the addition of gum tragacanth at a low concentration caused the density of the matrix to increase, while an open structure was observed in the presence of a higher gum concentration. Copyright © 2012 Elsevier B.V. All rights reserved.

  6. Electronic tracking of human resource skills and knowledge, just in time training, manageable due diligence

    Energy Technology Data Exchange (ETDEWEB)

    Kolodziej, M.A. [Quick Test International Inc., (Canada). Canadian Technology Human Resource Board; Baker, O. [KeySpan Energy Canada, Calgary, AB (Canada)

    2001-06-01

    KeySpan Energy Canada is in the process of obtaining recognition of various occupational profiles including pipeline operators, inspectors, and field and plant operators from various certifying organizations. The process of allowing individuals to obtain certification is recognized by Canadian Technology Human Resources Board as a step towards national standards for technologists and technicians. Proven competency is a must for workers in todays oil industry in response to increasingly stringent government safety regulations, environmental concerns and high public scrutiny. Quick Test international Inc. has developed a management tool in collaboration with end users at KeySpan Energy Canada. It is an electronic, Internet based competency tool for tracking personal competencies and maintaining continued competency. Response to the tool has been favourable. 2 refs., 4 figs.

  7. Availability, Use and Constraints to Use of Electronic Information Resources by Postgraduates Students at the University of Ibadan

    Directory of Open Access Journals (Sweden)

    Dare Samuel Adeleke

    2017-12-01

    Full Text Available Availability, awareness and use of electronic resources provide access to authoritative, reliable, accurate and timely access to information. The use of electronic information resources (EIRs can enable innovation in teaching and increase timeliness in research of postgraduate students which will eventual result into encouragement of the expected research-led enquiry in this digital age. The study adopted a descriptive survey design. Samples of 300 of postgraduate students within seven out 13 Faculties were randomly selected. Data were collected using questionnaire designed to elicit response from respondents and data were analyzed using descriptive statistics methods percentages, mean, and standard deviation. Results indicated that internet was ranked most available and used in the university. Low level of usage of electronic resources, in particular, full texts data bases is linked to a number of constraints: Interrupted power supply was ranked highest among other factors as speed and capacity of computers, retrieval of records with high recall and low precision, retrieving records relevant to information need, lack of knowledge of search techniques to retrieve information effectively, non possession of requisite IT skills and problems accessing the internet. The study recommended that usage of electronic resources be made compulsory, intensifying awareness campaigns concerning the availability, training on use of electronic resources and the problem of power outage be addressed.

  8. Using mobile electronic devices to deliver educational resources in developing countries.

    Science.gov (United States)

    Mazal, Jonathan Robert; Ludwig, Rebecca

    2015-01-01

    Developing countries have far fewer trained radiography professionals than developed countries, which exacerbates the limited access to imaging services. The lack of trained radiographers reflects, in part, limited availability of radiographer-specific educational resources. Historically, organizations that provided such resources in the developing world faced challenges related to the limited stock of current materials as well as expenses associated with shipping and delivery. Four mobile electronic devices (MEDs) were loaded with educational content (e-books, PDFs, and digital applications) spanning major radiography topics. The MEDs were distributed to 4 imaging departments in Ghana, India, Nepal, and Nigeria based on evidence of need for radiography-specific resources, as revealed by survey responses. A cost comparison of postal delivery vs digital delivery of educational content was performed. The effectiveness of delivering additional content via Wi-Fi transmission also was evaluated. Feedback was solicited on users' experience with the MEDs as a delivery tool for educational content. An initial average per e-book expense of $30.05, which included the cost of the device, was calculated for the MED delivery method compared with $15.56 for postal delivery of printed materials. The cost of the MED delivery method was reduced to an average of $10.05 for subsequent e-book deliveries. Additional content was successfully delivered via Wi-Fi transmission to all recipients during the 3-month follow-up period. Overall user feedback on the experience was positive, and ideas for enhancing the MED-based method were identified. Using MEDs to deliver radiography-specific educational content appears to be more cost effective than postal delivery of printed materials on a long-term basis. MEDs are more efficient for providing updates to educational materials. Customization of content to department needs, and using projector devices could enhance the usefulness of MEDs for

  9. Acceleration of gelation and promotion of mineralization of chitosan hydrogels by alkaline phosphatase

    NARCIS (Netherlands)

    Douglas, T.E.L.; Skwarczynska, A.; Modrzejewska, Z.; Balcaen, L.; Schaubroeck, D.; Lycke, S.; Vanhaecke, F.; Vandenabeele, P.; Dubruel, P.; Jansen, J.A.; Leeuwenburgh, S.C.G.

    2013-01-01

    Thermosensitive chitosan hydrogels containing sodium beta-glycerophosphate (beta-GP), whose gelation is induced by increasing temperature to body temperature, were functionalized by incorporation of alkaline phosphatase (ALP), an enzyme involved in mineralization of bone. ALP incorporation led to

  10. Solvent-mediated pathways to gelation and phase separation in suspensions of grafted nanoparticles

    KAUST Repository

    Anyfantakis, Manos; Bourlinos, Athanasios; Vlassopoulos, Dimitris; Fytas, George; Giannelis, Emmanuel; Kumar, Sanat K.

    2009-01-01

    , rheology and visual observations, and different routes to gelation, depending on the solvent used. In agreement with earlier works, the solvent quality for the grafted chains at a given temperature controls the balance between attractions and repulsions

  11. Dynamic covalent gels assembled from small molecules:from discrete gelators to dynamic covalent polymers

    Institute of Scientific and Technical Information of China (English)

    Jian-Yong Zhang; Li-Hua Zeng; Juan Feng

    2017-01-01

    Dynamic covalent chemistry has emerged recently to be a powerful tool to construct functional materials.This article reviews the progress in the research and development of dynamic covalent chemistry in gels assembled from small molecules.First dynamic covalent reactions used in gels are reviewed to understand the dynamic covalent bonding.Afterwards the catalogues of dynamic covalent gels are reviewed according to the nature of gelators and the interactions between gelators.Dynamic covalent bonding can be involved to form low molecular weight gelators.Low molecular weight molecules with multiple functional groups react to form dynamic covalent cross-linked polymers and act as gelators.Two catalogues of gels show different properties arising from their different structures.This review aims to illustrate the structure-property relationships of these dynamic covalent gels.

  12. The electronic encapsulation of knowledge in hydraulics, hydrology and water resources

    Science.gov (United States)

    Abbott, Michael B.

    The rapidly developing practice of encapsulating knowledge in electronic media is shown to lead necessarily to the restructuring of the knowledge itself. The consequences of this for hydraulics, hydrology and more general water-resources management are investigated in particular relation to current process-simulation, real-time control and advice-serving systems. The generic properties of the electronic knowledge encapsulator are described, and attention is drawn to the manner in which knowledge 'goes into hiding' through encapsulation. This property is traced in the simple situations of pure mathesis and in the more complex situations of taxinomia using one example each from hydraulics and hydrology. The consequences for systems architectures are explained, pointing to the need for multi-agent architectures for ecological modelling and for more general hydroinformatics systems also. The relevance of these developments is indicated by reference to ongoing projects in which they are currently being realised. In conclusion, some more general epistemological aspects are considered within the same context. As this contribution is so much concerned with the processes of signification and communication, it has been partly shaped by the theory of semiotics, as popularised by Eco ( A Theory of Semiotics, Indiana University, Bloomington, 1977).

  13. Plastics disassembly versus bulk recycling: engineering design for end-of-life electronics resource recovery.

    Science.gov (United States)

    Rios, Pedro; Stuart, Julie Ann; Grant, Ed

    2003-12-01

    Annual plastic flows through the business and consumer electronics manufacturing supply chain include nearly 3 billion lb of high-value engineering plastics derived from petroleum. The recovery of resource value from this stream presents critical challenges in areas of materials identification and recycling process design that demand new green engineering technologies applied together with life cycle assessment and ecological supply chain analysis to create viable plastics-to-plastics supply cycles. The sustainable recovery of potentially high-value engineering plastics streams requires that recyclers either avoid mixing plastic parts or purify later by separating smaller plastic pieces created in volume reduction (shredding) steps. Identification and separation constitute significant barriers in the plastics-to-plastics recycling value proposition. In the present work, we develop a model that accepts randomly arriving electronic products to study scenarios by which a recycler might identify and separate high-value engineering plastics as well as metals. Using discrete eventsimulation,we compare current mixed plastics recovery with spectrochemical plastic resin identification and subsequent sorting. Our results show that limited disassembly with whole-part identification can produce substantial yields in separated streams of recovered engineering thermoplastics. We find that disassembly with identification does not constitute a bottleneck, but rather, with relatively few workers, can be configured to pull the process and thus decrease maximum staging space requirements.

  14. Structural and solubility parameter correlations of gelation abilities for dihydroxylated derivatives of long-chain, naturally occurring fatty acids.

    Science.gov (United States)

    Zhang, Mohan; Selvakumar, Sermadurai; Zhang, Xinran; Sibi, Mukund P; Weiss, Richard G

    2015-06-01

    Creating structure-property correlations at different distance scales is one of the important challenges to the rational design of molecular gelators. Here, a series of dihydroxylated derivatives of long-chain fatty acids, derived from three naturally occurring molecules-oleic, erucic and ricinoleic acids-are investigated as gelators of a wide variety of liquids. Conclusions about what constitutes a more (or less!) efficient gelator are based upon analyses of a variety of thermal, structural, molecular modeling, and rheological results. Correlations between the manner of molecular packing in the neat solid or gel states of the gelators and Hansen solubility data from the liquids leads to the conclusion that diol stereochemistry, the number of carbon atoms separating the two hydroxyl groups, and the length of the alkanoic chains are the most important structural parameters controlling efficiency of gel formation for these gelators. Some of the diol gelators are as efficient or even more efficient than the well-known, excellent gelator, (R)-12-hydroxystearic acid; others are much worse. The ability to form extensive intermolecular H-bonding networks along the alkyl chains appears to play a key role in promoting fiber growth and, thus, gelation. In toto, the results demonstrate how the efficiency of gelation can be modulated by very small structural changes and also suggest how other structural modifications may be exploited to create efficient gelators. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Alginate gelation-induced cell death during laser-assisted cell printing

    International Nuclear Information System (INIS)

    Gudapati, Hemanth; Yan, Jingyuan; Huang, Yong; Chrisey, Douglas B

    2014-01-01

    Modified laser-induced forward transfer has emerged as a promising bioprinting technique. Depending on the operating conditions and cell properties, laser cell printing may cause cell injury and even death, which should be carefully elucidated for it to be a viable technology. This study has investigated the effects of alginate gelation, gelation time, alginate concentration, and laser fluence on the post-transfer cell viability of NIH 3T3 fibroblasts. Sodium alginate and calcium chloride are used as the gel precursor and gel reactant solution to form cell-laden alginate microspheres. It is found that the effects of gelation depend on the duration of gelation. Two-minute gelation is observed to increase the cell viability after 24 h incubation, mainly due to the protective cushion effect of the forming gel membrane during droplet landing. Despite the cushion effect from 10 min gelation, it is observed that the cell viability decreases after 24 h incubation because of the forming thick gel membrane that reduces nutrient and oxygen diffusion from the culture medium. In addition, the cell viability after 24 h incubation decreases as the laser fluence or alginate concentration increases. (paper)

  16. SAGES: a suite of freely-available software tools for electronic disease surveillance in resource-limited settings.

    Directory of Open Access Journals (Sweden)

    Sheri L Lewis

    Full Text Available Public health surveillance is undergoing a revolution driven by advances in the field of information technology. Many countries have experienced vast improvements in the collection, ingestion, analysis, visualization, and dissemination of public health data. Resource-limited countries have lagged behind due to challenges in information technology infrastructure, public health resources, and the costs of proprietary software. The Suite for Automated Global Electronic bioSurveillance (SAGES is a collection of modular, flexible, freely-available software tools for electronic disease surveillance in resource-limited settings. One or more SAGES tools may be used in concert with existing surveillance applications or the SAGES tools may be used en masse for an end-to-end biosurveillance capability. This flexibility allows for the development of an inexpensive, customized, and sustainable disease surveillance system. The ability to rapidly assess anomalous disease activity may lead to more efficient use of limited resources and better compliance with World Health Organization International Health Regulations.

  17. Production and characterization of nanocapsules encapsulated linalool by ionic gelation method using chitosan as wall material

    Directory of Open Access Journals (Sweden)

    Zuobing XIAO

    Full Text Available Abstract Linalool has been extensively applied in various fields, such as flavoring agent, perfumes, cosmetics and medical science. However, linalool is unstable, volatile and readily oxidizable. A sensitive substance can be encapsulated in a capsule, so encapsulation technology can solve these problems. In this paper, linalool-loaded nanocapsules (Lin-nanocapsules were prepared via the ionic gelation method and Lin-nanocapsules were characterized. The results of Fourier transformation infrared spectroscopy (FTIR showed that linalool was successfully encapsulated in the wall materials. Scanning electron microscopy (SEM results demonstrated that the shapes of Lin-nanocapsules, with smooth surfaces, were nearly spherical. Lin-nanocapsule average particle size was 352 nm and its polydispersity index (PDI was proved to be 0.214 by the results of dynamic light scattering (DLC. Thermogravimetric results indicated that linalool loading capacity (LC was 15.17%, and encapsulation could decrease linalool release and increase linalool retaining time under the high temperature. Oscillatory shear and steady-state shear measurements of Lin-nanocapsule emulsions were systematically investigated. The results of steady-state shear showed that Lin-nanocapsule emulsion, which was Newtonian only for high shear rate, was non-Newtonian. It was proved by oscillatory shear that when oscillation frequency changed from low to high, Lin-nanocapsules emulsion changed from viscous into elastic.

  18. Incorporation of essential oil in alginate microparticles by multiple emulsion/ionic gelation process.

    Science.gov (United States)

    Hosseini, Seyede Marzieh; Hosseini, Hedayat; Mohammadifar, Mohammad Amin; Mortazavian, Amir Mohammad; Mohammadi, Abdorreza; Khosravi-Darani, Kianoosh; Shojaee-Aliabadi, Saeedeh; Dehghan, Solmaz; Khaksar, Ramin

    2013-11-01

    In this study, an o/w/o multiple emulsion/ionic gelation method was developed for production of alginate microparticles loaded with Satureja hortensis essential oil (SEO). It was found that the essential oil concentration has significant influence on encapsulation efficiency (EE), loading capacity (LC) and size of microparticles. The values of EE, LC and particle mean diameter were about 52-66%, 20-26%, and 47-117 μm, respectively, when the initial SEO content was 1-3% (v/v) .The essential oil-loaded microparticles were porous, as displayed by scanning electron micrograph. The presence of SEO in alginate microparticles was confirmed by Fourier transform-infrared (FT-IR) spectroscopy and differential scanning calorimetry (DSC) analyses. SEO-loaded microparticles showed good antioxidant (with DPPH radical scavenging activity of 40.7-73.5%) and antibacterial properties; this effect was greatly improved when the concentration of SEO was 3% (v/v). S. aureus was found to be the most sensitive bacterium to SEO and showed a highest inhibition zone of 304.37 mm(2) in the microparticles incorporated with 3% (v/v) SEO. In vitro release studies showed an initial burst release and followed by a slow release. In addition, the release of SEO from the microparticles followed Fickian diffusion with acceptable release. Copyright © 2013 Elsevier B.V. All rights reserved.

  19. DSC and TMA studies on freezing and thawing gelation of galactomannan polysaccharide

    International Nuclear Information System (INIS)

    Iijima, Mika; Hatakeyama, Tatsuko; Hatakeyama, Hyoe

    2012-01-01

    Research highlights: ► Locust bean gum forms hydrogels by freezing and thawing. ► Syneresis was observed when freezing and thawing cycle (n) increased. ► Dynamic Young's modulus increased with increasing n. ► Non-freezing water content restrained by hydrogels decreased with increasing n. ► Strong gel with densely packed network structure formed with increasing n. - Abstract: Among various kinds of polysaccharides known to form hydrogels, locust bean gum (LBG) consisting of a mannose backbone and galactose side chains has unique characteristics, since LBG forms hydrogels by freezing and thawing. In this study, effect of thermal history on gelation was investigated by differential scanning calorimetry (DSC) and thermomechanical analysis (TMA). Gel/sol ratio calculated by weighing method was found to be affected by sol concentration, freezing rate and the number of freezing and thawing cycle (n). Once LBG hydrogels are formed, they are thermally stable, although syneresis was observed when n increased. Dynamic Young's modulus (E′) of hydrogels measured by TMA in water increased with increasing n and decreasing freezing rate. Non-freezing water calculated from DSC melting peak of ice in the gel decreased with increasing n and decreasing freezing rate. Morphological observation of freeze-dried gels was carried out by scanning electron microscopy (SEM). The above results indicate that weak hydrogel having large molecular network structure transformed into strong gel with densely packed network structure by increasing n and decreasing freezing rate.

  20. Insight on the formation of chitosan nanoparticles through ionotropic gelation with tripolyphosphate.

    Science.gov (United States)

    Koukaras, Emmanuel N; Papadimitriou, Sofia A; Bikiaris, Dimitrios N; Froudakis, George E

    2012-10-01

    This work reports details pertaining to the formation of chitosan nanoparticles that we prepare by the ionic gelation method. The molecular interactions of the ionic cross-linking of chitosan with tripolyphosphate have been investigated and elucidated by means of all-electron density functional theory. Solvent effects have been taken into account using implicit models. We have identified primary-interaction ionic cross-linking configurations that we define as H-link, T-link, and M-link, and we have quantified the corresponding interaction energies. H-links, which display high interaction energies and are also spatially broadly accessible, are the most probable cross-linking configurations. At close range, proton transfer has been identified, with maximum interaction energies ranging from 12.3 up to 68.3 kcal/mol depending on the protonation of the tripolyphosphate polyanion and the relative coordination of chitosan with tripolyphosphate. On the basis of our results for the linking types (interaction energies and torsion bias), we propose a simple mechanism for their impact on the chitosan/TPP nanoparticle formation process. We introduce the β ratio, which is derived from the commonly used α ratio but is more fundamental since it additionally takes into account structural details of the oligomers.

  1. Self-Healing Phase Change Salogels with Tunable Gelation Temperature.

    Science.gov (United States)

    Karimineghlani, Parvin; Palanisamy, Anbazhagan; Sukhishvili, Svetlana A

    2018-04-19

    Chemically cross-linked polymer matrices have demonstrated strong potential for shape stabilization of molten phase change materials (PCM). However, they are not designed to be fillable and removable from a heat exchange module for an easy replacement with new PCM matrices and lack self-healing capability. Here, a new category of shapeable, self-healing gels, "salogels", is introduced. The salogels reversibly disassemble in a high-salinity environment of a fluid inorganic PCM [lithium nitrate trihydrate (LNH)], at a preprogrammed temperature. LNH was employed as a high latent heat PCM and simultaneously as a solvent, which supported the formation of a network of polyvinyl alcohol (PVA) chains via physical cross-linking through poly(amidoamine) dendrimers of various generations. The existence of hydrogen bonding and the importance of low-hydration state of PVA for the efficient gelation were experimentally confirmed. The thermal behavior of PCM salogels was highly reversible and repeatable during multiple heating/cooling cycles. Importantly, the gel-sol transition temperature could be precisely controlled within a range of temperature above LNH's melting point by the choice of dendrimer generation and their concentration. Shape stabilization and self-healing properties of the salogels, taken together with tunability of their temperature-induced fluidization make these materials attractive for thermal energy storage applications that require on-demand removal and replacement of used inorganic PCM salt hydrates.

  2. Washing of Uranium Gel Resulted from Gelation Using Ammonia

    International Nuclear Information System (INIS)

    Nurwijayadi; Bangun-Wasito; Sukarsono; Endang-Nawangsih

    2000-01-01

    Washing of uranium gel resulted from gelation using ammonia underconcentration of 1, 2.5, 3, 4 and 5 % has been carried out. The sol wasprepared by reacting uranyl nitrate, urea and HMTA at 5 o C. The resulted solwas dropped into a column containing paraffin oil at temperature of 95 o C.The resulted gel color was orange. It was simmered in a 2.5 % ammoniasolution for 24 hours. After that, the gel was washed in an ammonia solutionunder a concentration variation. The best washing process occurred at ammoniaconcentration of 2.5 % with most absorbed ion nitrate, i.e. 292.2 ppm. Theresulted true density using N 2 was about 8.3 - 8.6 g/ml, specific surfacearea using multi point BET was about 1.5 - 3.1 m 2 /g, average pore radius was22.27 -41.22 A and total pore volume was 3.55 x 10 -3 cc/g. (author)

  3. Electronic Human Resources Management (e-HRM Adoption Studies: Past and Future Research

    Directory of Open Access Journals (Sweden)

    Winarto Winarto

    2018-05-01

    Full Text Available Electronic human resource management (e-HRM systems become more widely used by profit and non-profit organization. However, the field currently lacks sound theoretical frameworks that can be useful in addressing a key issue concerning the implementation of e-HRM systems, in particular to obtain a better understanding of the factors influencing the adoption of e-HRM systems. The objective of this paper is to provide a foundation towards the development of a theoretical framework for the implementation of e-HRM systems and develop a conceptual model that would reflect the nature of e-HRM systems’ adoption through systematic literature review. Adopting Crossan and Apaydin’s procedure of systematic review, this paper investigated 21 empirical papers of electronics human resources management, then categorized them into 4 characteristics which influence the adoption; System and technology characteristics; Organizational characteristics; User/individual characteristics, and Environmental and contextual characteristics. Finally, the e-HRM adoption research framework is drawn and based on the framework; avenues for future research are discussed.   Bahasa Indonesia Abstrak: Manajemen sumber daya manusia elektronik (selanjutnya disebut dengan e-HRM semakin banyak digunakan oleh organisasi profit dan nonprofit. Namun, bidang dan topik ini belum memiliki kerangka teori yang mapan, yang dapat digunakan untuk menganalisis isu-isu terkait penerapan e-HRM, terutama mengenai faktor-faktor yang mempengaruhi adopsi sistem e-HRM. Tujuan penelitian ini adalah untuk memberikan landasan bagi pengembangan kerangka teoritis untuk implementasi sistem e-HRM dan mengembangkan model konseptual yang akan menggambarkan adopsi sistem e-HRM melalui tinjauan literatur sistematis. Mengadopsi prosedur dan metode Crossan dan Apaydin untuk melakukan telaah literatur secara sistematis, paper ini menyelidiki 21 publikasi empiris manajemen sumber daya manusia elektronik dari 2

  4. Process and equipment development for the preparation of UO2 microspheres using trichloroethylene as gelation medium (Paper No. AL-23)

    International Nuclear Information System (INIS)

    Suryanarayana, S.; Kumar, N.; Bamankar, Y.R.; Vaidya, V.N.; Sood, D.D.

    1990-02-01

    Uranium dioxide microspheres have been prepared by internal gelation process, one of the sol-gel routes for fuel fabrication. The process flow sheet for internal gelation has been modified by employing trichloroethylene(TCE) as an alternate gelation medium. Based on the modified flow sheet, a 5Kg/day assembly for the production of UO 2 microspheres has been developed and installed. (author). 1 fig

  5. Fabrication of uranium-based ceramics using internal gelation for the conversion of trivalent actinides

    International Nuclear Information System (INIS)

    Daniels, Henrik

    2012-01-01

    Alternative to today's direct final waste disposal strategy of long-lived radionuclides, for example the minor actinides neptunium, americium, curium and californium, is their selective separation from the radioactive wastestream with subsequent transmutation by neutron irradiation. Hereby it is possible to obtain nuclides with a lower risk-potential concerning their radiotoxicity. 1 neutron irradiation can be carried out either with neutron sources or in the next generation of nuclear reactors. Before the treatment, the minor actinides need to be converted in a suitable chemical and physical form. Internal gelation offers a route through which amorphous gel-spheres can be obtained directly from a metal-salt solution. Due to the presence of different types of metal ions as well as changing pH-values in a stock solution, a complex hydrolysis behaviour of these elements before and during gelation occurs. Therefore, investigations with uranium and neodymium as a minor actinide surrogate were carried out. As a result of suitable gelation-parameters, uraniumneodymium gel-spheres were successfully synthesised. The spheres also stayed intact during the subsequent thermal treatment. Based upon these findings, uranium-plutonium and uranium-americium gels were successfully created. For theses systems, the determined parameters for the uraniumneodymium gelation could also be applied. Additionally, investigations to reduce the acidity of uranium-based stock solutions for internal gelation were carried out. The necessary amount of urea and hexamethylenetetramine to induce gelation could hereby be decreased. This lead to a general increase of the gel quality and made it possible to carry out uranium-americium gelation in the first place. To investigate the stability of urea and hexamethylenetetramine, solutions of these chemicals were irradiated with different radiation doses. These chemicals showed a high stability against radiolysis in aqueous solutions.

  6. Impact of Electronic Resources and Usage in Academic Libraries in Ghana: Evidence from Koforidua Polytechnic & All Nations University College, Ghana

    Science.gov (United States)

    Akussah, Maxwell; Asante, Edward; Adu-Sarkodee, Rosemary

    2015-01-01

    The study investigates the relationship between impact of electronic resources and its usage in academic libraries in Ghana: evidence from Koforidua Polytechnic & All Nations University College, Ghana. The study was a quantitative approach using questionnaire to gather data and information. A valid response rate of 58.5% was assumed. SPSS…

  7. Utilization of Electronic Information Resources by Undergraduate Students of University of Ibadan: A Case Study of Social Sciences and Education

    Science.gov (United States)

    Owolabi, Sola; Idowu, Oluwafemi A.; Okocha, Foluke; Ogundare, Atinuke Omotayo

    2016-01-01

    The study evaluated utilization of electronic information resources by undergraduates in the Faculties of Education and the Social Sciences in University of Ibadan. The study adopted a descriptive survey design with a study population of 1872 undergraduates in the Faculties of Education and the Social Sciences in University of Ibadan, from which a…

  8. Systematic review of electronic surveillance of infectious diseases with emphasis on antimicrobial resistance surveillance in resource-limited settings.

    Science.gov (United States)

    Rattanaumpawan, Pinyo; Boonyasiri, Adhiratha; Vong, Sirenda; Thamlikitkul, Visanu

    2018-02-01

    Electronic surveillance of infectious diseases involves rapidly collecting, collating, and analyzing vast amounts of data from interrelated multiple databases. Although many developed countries have invested in electronic surveillance for infectious diseases, the system still presents a challenge for resource-limited health care settings. We conducted a systematic review by performing a comprehensive literature search on MEDLINE (January 2000-December 2015) to identify studies relevant to electronic surveillance of infectious diseases. Study characteristics and results were extracted and systematically reviewed by 3 infectious disease physicians. A total of 110 studies were included. Most surveillance systems were developed and implemented in high-income countries; less than one-quarter were conducted in low-or middle-income countries. Information technologies can be used to facilitate the process of obtaining laboratory, clinical, and pharmacologic data for the surveillance of infectious diseases, including antimicrobial resistance (AMR) infections. These novel systems require greater resources; however, we found that using electronic surveillance systems could result in shorter times to detect targeted infectious diseases and improvement of data collection. This study highlights a lack of resources in areas where an effective, rapid surveillance system is most needed. The availability of information technology for the electronic surveillance of infectious diseases, including AMR infections, will facilitate the prevention and containment of such emerging infectious diseases. Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.

  9. Gelation of photopolymerized hyaluronic acid grafted with glycidyl methacrylate

    International Nuclear Information System (INIS)

    Prado, S.S.; Weaver, J.M.; Love, B.J.

    2011-01-01

    Experiments have tracked the ambient gelation of a series of hydrophilic hyaluronic acid (HA) resins grafted with glycidyl methacrylate (GM) and photopolymerized as a function of dose. The resin mixtures range in GMHA concentration between 0.5 and 1.5% w/w in phosphate buffered saline (PBS). Illuminated at 20 mW/cm 2 , the dynamic viscosity (η(t)) has been tracked and characterized using the Boltzmann log-sigmoidal model. A gelled viscosity of ∼ 10 Pa s was determined at 0.5% w/w which rose to ∼ 50 Pa s at or above 1% w/w. More curing agent marginally increased the gel viscosity at each concentration. Time constants associated with viscosity advancement were shortest at [GMHA] = 1.0%; higher concentrations are attributed with lower quantum efficiency when illuminated. Subsequent frequency sweeps replicated already published work using similar GHMA concentrations in PBS. G' values ranged from 100 to 500 Pa over the formulation range with expected sensitivity to GMHA and curing agent concentration. Overall, the sigmoidal model represented this advancing viscosity data well, and further analysis of the physical significance of these model parameters may help in understanding photopolymerization of this complicated formulation more broadly. Highlights: → The ambient dynamic viscosity of photopolymerized GMHA gels has been measured. → 2 physical parameters and two time constants were extracted from the sigmoidal model. → Higher crosslinker content for a fixed GMHA concentration led to higher gel viscosity. → The time to toggle between the initial and final viscosity ranged between 5 and 10 s. → Dynamic frequency sweep tests on cured gels also revealed G' values between 100 and 500 Pa.

  10. Thermal gelation and tissue adhesion of biomimetic hydrogels

    International Nuclear Information System (INIS)

    Burke, Sean A; Ritter-Jones, Marsha; Lee, Bruce P; Messersmith, Phillip B

    2007-01-01

    Marine and freshwater mussels are notorious foulers of natural and manmade surfaces, secreting specialized protein adhesives for rapid and durable attachment to wet substrates. Given the strong and water-resistant nature of mussel adhesive proteins, significant potential exists for mimicking their adhesive characteristics in bioinspired synthetic polymer materials. An important component of these proteins is L-3,4-dihydroxylphenylalanine (DOPA), an amino acid believed to contribute to mussel glue solidification through oxidation and crosslinking reactions. Synthetic polymers containing DOPA residues have previously been shown to crosslink into hydrogels upon the introduction of oxidizing reagents. Here we introduce a strategy for stimuli responsive gel formation of mussel adhesive protein mimetic polymers. Lipid vesicles with a bilayer melting transition of 37 0 C were designed from a mixture of dipalmitoyl and dimyristoyl phosphatidylcholines and exploited for the release of a sequestered oxidizing reagent upon heating from ambient to physiologic temperature. Colorimetric studies indicated that sodium-periodate-loaded liposomes released their cargo at the phase transition temperature, and when used in conjunction with a DOPA-functionalized poly(ethylene glycol) polymer gave rise to rapid solidification of a crosslinked polymer hydrogel. The tissue adhesive properties of this biomimetic system were determined by in situ thermal gelation of liposome/polymer hydrogel between two porcine dermal tissue surfaces. Bond strength measurements showed that the bond formed by the adhesive hydrogel (mean = 35.1 kPa, SD = 12.5 kPa, n = 11) was several times stronger than a fibrin glue control tested under the same conditions. The results suggest a possible use of this biomimetic strategy for repair of soft tissues

  11. The Use of Electronic Resources by Academic Staff at the University of Ilorin, Nigeria

    Science.gov (United States)

    Tella, Adeyinka; Orim, Faith; Ibrahim, Dauda Morenikeji; Memudu, Suleiman Ajala

    2018-01-01

    The use of e-resources is now commonplace among academics in tertiary educational institutions the world over. Many academics including those in the universities are exploring the opportunities of e-resources to facilitate teaching and research. As the use of e-resources is increasing particularly among academics at the University of Ilorin,…

  12. Modeling antecedents of electronic medical record system implementation success in low-resource setting hospitals.

    Science.gov (United States)

    Tilahun, Binyam; Fritz, Fleur

    2015-08-01

    With the increasing implementation of Electronic Medical Record Systems (EMR) in developing countries, there is a growing need to identify antecedents of EMR success to measure and predict the level of adoption before costly implementation. However, less evidence is available about EMR success in the context of low-resource setting implementations. Therefore, this study aims to fill this gap by examining the constructs and relationships of the widely used DeLone and MacLean (D&M) information system success model to determine whether it can be applied to measure EMR success in those settings. A quantitative cross sectional study design using self-administered questionnaires was used to collect data from 384 health professionals working in five governmental hospitals in Ethiopia. The hospitals use a comprehensive EMR system since three years. Descriptive and structural equation modeling methods were applied to describe and validate the extent of relationship of constructs and mediating effects. The findings of the structural equation modeling shows that system quality has significant influence on EMR use (β = 0.32, P quality has significant influence on EMR use (β = 0.44, P service quality has strong significant influence on EMR use (β = 0.36, P effect of EMR use on user satisfaction was not significant. Both EMR use and user satisfaction have significant influence on perceived net-benefit (β = 0.31, P mediating factor in the relationship between service quality and EMR use (P effect on perceived net-benefit of health professionals. EMR implementers and managers in developing countries are in urgent need of implementation models to design proper implementation strategies. In this study, the constructs and relationships depicted in the updated D&M model were found to be applicable to assess the success of EMR in low resource settings. Additionally, computer literacy was found to be a mediating factor in EMR use and user satisfaction of

  13. Synergistic enhancement in the co-gelation of salt-soluble pea proteins and whey proteins.

    Science.gov (United States)

    Wong, Douglas; Vasanthan, Thava; Ozimek, Lech

    2013-12-15

    This paper investigated the enhancement of thermal gelation properties when salt-soluble pea proteins were co-gelated with whey proteins in NaCl solutions, using different blend ratios, total protein concentrations, pH, and salt concentrations. Results showed that the thermal co-gelation of pea/whey proteins blended in ratio of 2:8 in NaCl solutions showed synergistic enhancement in storage modulus, gel hardness, paste viscosity and minimum gelation concentrations. The highest synergistic enhancement was observed at pH 6.0 as compared with pH 4.0 and 8.0, and at the lower total protein concentration of 10% as compared with 16% and 22% (w/v), as well as in lower NaCl concentrations of 0.5% and 1.0% as compared with 1.5%, 2.0%, 2.5%, and 3.0% (w/v). The least gelation concentrations were also lower in the different pea/whey protein blend ratios than in pure pea or whey proteins, when dissolved in 1.0% or 2.5% (w/v) NaCl aqueous solutions. Copyright © 2013 Elsevier Ltd. All rights reserved.

  14. Studies on gelation of sodium silicate hydrosol for immobilization of high level liquid waste (HLLW).

    Energy Technology Data Exchange (ETDEWEB)

    Abdel Raouf, M W [Hot Lab. Centre, Atomic Energy Authority, Cairo (Egypt); Sharaf El-deen, A N; El-Dessouky, M M [Military Technical College, Kobry El-Kobbah, Cairo (Egypt)

    1995-10-01

    Immobilization of the simulated high-level liquid waste (HLLW) was performed via the gelation with sodium silicate hydrosol at room temperature. The simulated waste in this study, was represented by the electrolytes of Li, Na, K, Cs, Co and Sr at different concentrations. Specific loading of the liquid waste with 0.6 M Mg (NO{sub 3})2 and tailoring with Al salts were tried during most of the gelation processes. Mineral acid (HCl or {sub 3}) were added during the gelation processes to achieve the gel point, especially when lower concentrations of the simulated waste were used. The obtained hydrogel were dried to obtain the solid gel form. The gelation processes were investigated in terms of the different factors that affected them, namely: temperature, pH, changes in the concentration of the initial hydrosol and the used electrolytes. The efficiency of the gelation processes was investigated from the ratio of the amount of simulated waste reacted (m mole) to the initial silicate used (m mole), i.e. X value. Lower X values were observed when using multi valent cations (higher polarizing power). A special effect of increasing the sorption of metal cations in the silica matrix was observed when Al{sup 3+} replaced Si{sup 4+} in the three-dimensional network structure of the matrix. 3 figs., 7 tabs.

  15. Use and Cost of Electronic Resources in Central Library of Ferdowsi University Based on E-metrics

    Directory of Open Access Journals (Sweden)

    Mohammad Reza Davarpanah

    2012-07-01

    Full Text Available The purpose of this study was to investigate the usage of electronic journals in Ferdowsi University, Iran based on e-metrics. The paper also aimed to emphasize the analysis of cost-benefit and the correlation between the journal impact factors and the usage data. In this study experiences of Ferdowsi University library on licensing and usage of electronic resources was evaluated by providing a cost-benefit analysis based on the cost and usage statistics of electronic resources. Vendor-provided data were also compared with local usage data. The usage data were collected by tracking web-based access locally, and by collecting vender-provided usage data. The data sources were one-year of vendor-supplied e-resource usage data such as Ebsco, Elsevier, Proquest, Emerald, Oxford and Springer and local usage data collected from the Ferdowsi university web server. The study found that actual usage values differ for vendor-provided data and local usage data. Elsevier has got the highest usage degree in searches, sessions and downloads. Statistics also showed that a small number of journals satisfy significant amount of use while the majority of journals were used less frequent and some were never used at all. The users preferred the PDF rather than HTML format. The data in subject profile suggested that the provided e-resources were best suited to certain subjects. There was no correlation between IF and electronic journal use. Monitoring the usage of e-resources gained increasing importance for acquisition policy and budget decisions. The article provided information about local metrics for the six surveyed vendors/publishers, e.g. usage trends, requests per package, cost per use as related to the scientific specialty of the university.

  16. Microspheres Prepared by Internal Gelation - Understanding of HMTA and urea reactions

    International Nuclear Information System (INIS)

    Robisson, A.C.; Dauby, J.; Grandjean, S.; Benay, G.; Modolo, G.

    2008-01-01

    Homogenous microspheres of minor actinide (hereafter MA) compounds are of interest to prevent the generation and dispersal of MA powder at the early stages of the fabrication of targets for homogenous or heterogeneous transmutation. Sol-gel routes are being investigated as one of the possible solutions for producing these homogeneous starting materials. This document describes internal gelation basis experiments led at Cea Marcoule and at the Institute for Energy Research Juelich dedicated to the synthesis of mixed compounds including MAs, particularly mixed actinide-actinide or mixed actinide-inert element compounds. Parameter studies were undertaken by simulating cations in order to scan a larger range of conditions and to optimise more easily gelation conditions. With these experiments, key parameters were put forward and the main successive reactions taking care during gelation were understood. (authors)

  17. SANS study of understanding mechanism of cold gelation of globular proteins

    International Nuclear Information System (INIS)

    Chinchalikar, A. J.; Kumar, Sugam; Aswal, V. K.; Wagh, A. G.; Kohlbrecher, J.

    2014-01-01

    Small-angle neutron scattering (SANS) has been used to probe the evolution of interaction and the resultant structures in the cold gelation of globular proteins. The cold gelation involves two steps consisting of irreversible protein deformation by heating followed by some means (e.g. increasing ionic strength) to bring them together at room temperature. We have examined the role of different salts in cold gelation of preheated aqueous Bovine Serum Albumin (BSA) protein solutions. The interactions have been modeled by two Yukawa potential combining short-range attraction and long-range repulsion. We show that in step 1 (preheated temperature effect) the deformation of protein increases the magnitude of attractive interaction but not sufficient to induce gel. The attractive interaction is further enhanced in step 2 (salt effect) to result in gel formation. The salt effect is found to be strongly depending on the valency of the counterions. The gel structure has been characterized by the mass fractals

  18. Nanospheres of alginate prepared through w/o emulsification and internal gelation with nanoparticles of CaCO3

    NARCIS (Netherlands)

    Paques, J.P.; Sagis, L.M.C.; Rijn, van C.J.M.; Linden, van der E.

    2014-01-01

    Gelled nanospheres of alginate are prepared through a single step technique involving emulsification and gelation. CaCO3 nanoparticles, together with glucono delta-lactone (GDL), are dispersed in an alginate solution, which is subsequently dispersed in an oil phase and followed by gelation of the

  19. Use and User Perception of Electronic Information Resources: A Case Study of Siva Institute of Frontier Technology, India

    Directory of Open Access Journals (Sweden)

    Velmurugan Chandran

    2013-12-01

    Full Text Available The present study aims to explore the use and user perception of electronic resources in Siva Institute of Frontier Technology, India. A total number of 123 users were taken into account for the study through a questionnaire-based survey method. A well-structured questionnaire was designed and distributed to the selected 200 students and staff members. 123 copies of the questionnaires were returned dully filled in and the overall response rate was 61.50 percent. The questionnaire contained both open- and close-ended questions. The collected data were classified, analyzed, and tabulated by using simple statistical methods. This study covers the impact of electronic resources on students and faculty in their academic pursuit.

  20. Challenges in the implementation of an electronic surveillance system in a resource-limited setting: Alerta, in Peru

    Directory of Open Access Journals (Sweden)

    Soto Giselle

    2008-11-01

    Full Text Available Abstract Background Infectious disease surveillance is a primary public health function in resource-limited settings. In 2003, an electronic disease surveillance system (Alerta was established in the Peruvian Navy with support from the U.S. Naval Medical Research Center Detachment (NMRCD. Many challenges arose during the implementation process, and a variety of solutions were applied. The purpose of this paper is to identify and discuss these issues. Methods This is a retrospective description of the Alerta implementation. After a thoughtful evaluation according to the Centers for Disease Control and Prevention (CDC guidelines, the main challenges to implementation were identified and solutions were devised in the context of a resource-limited setting, Peru. Results After four years of operation, we have identified a number of challenges in implementing and operating this electronic disease surveillance system. These can be divided into the following categories: (1 issues with personnel and stakeholders; (2 issues with resources in a developing setting; (3 issues with processes involved in the collection of data and operation of the system; and (4 issues with organization at the central hub. Some of the challenges are unique to resource-limited settings, but many are applicable for any surveillance system. For each of these challenges, we developed feasible solutions that are discussed. Conclusion There are many challenges to overcome when implementing an electronic disease surveillance system, not only related to technology issues. A comprehensive approach is required for success, including: technical support, personnel management, effective training, and cultural sensitivity in order to assure the effective deployment of an electronic disease surveillance system.

  1. RESEARCH OF INFLUENCE OF QUALITY OF ELECTRONIC EDUCATIONAL RESOURCES ON QUALITY OF TRAINING WITH USE OF DISTANCE TECHNOLOGIES

    Directory of Open Access Journals (Sweden)

    H. M. Kravtsov

    2013-03-01

    Full Text Available Communication improving of educational processes requires today new approaches to the management arrangements and forming of educational policy in the field of distance learning, which is based on the use of modern information and communication technologies. An important step in this process is the continuous monitoring of the development and implementation of information technology and, in particular, the distance learning systems in higher educational establishments. The main objective of the monitoring is the impact assessment on the development of distance learning following the state educational standards, curricula, methodical and technical equipment and other factors; factors revelation that influence the implementation and outcomes of distance learning; results comparison of educational institution functioning and distance education systems in order to determine the most efficient ways of its development. The paper presents the analysis results of the dependence of the quality of educational services on the electronic educational resources. Trends in educational services development was studied by comparing the quality influence of electronic educational resources on the quality of educational services of higher pedagogical educational institutions of Ukraine as of 2009-2010 and 2012-2013. Generally, the analysis of the survey results allows evaluating quality of the modern education services as satisfactory and it can be said that almost 70% of the success of their future development depends on the quality of the used electronic educational resources and distance learning systems in particular.

  2. Tracking the Flow of Resources in Electronic Waste - The Case of End-of-Life Computer Hard Disk Drives.

    Science.gov (United States)

    Habib, Komal; Parajuly, Keshav; Wenzel, Henrik

    2015-10-20

    Recovery of resources, in particular, metals, from waste flows is widely seen as a prioritized option to reduce their potential supply constraints in the future. The current waste electrical and electronic equipment (WEEE) treatment system is more focused on bulk metals, where the recycling rate of specialty metals, such as rare earths, is negligible compared to their increasing use in modern products, such as electronics. This study investigates the challenges in recovering these resources in the existing WEEE treatment system. It is illustrated by following the material flows of resources in a conventional WEEE treatment plant in Denmark. Computer hard disk drives (HDDs) containing neodymium-iron-boron (NdFeB) magnets were selected as the case product for this experiment. The resulting output fractions were tracked until their final treatment in order to estimate the recovery potential of rare earth elements (REEs) and other resources contained in HDDs. The results further show that out of the 244 kg of HDDs treated, 212 kg comprising mainly of aluminum and steel can be finally recovered from the metallurgic process. The results further demonstrate the complete loss of REEs in the existing shredding-based WEEE treatment processes. Dismantling and separate processing of NdFeB magnets from their end-use products can be a more preferred option over shredding. However, it remains a technological and logistic challenge for the existing system.

  3. HELP (INFORMATION ELECTRONIC RESOURCE "CHRONICLE OF ONU: DATES, FACTS, EVENTS": HISTORY OF UNIVERSITY IN INFORMATION SPACE

    Directory of Open Access Journals (Sweden)

    А. М. Гавриленко

    2016-03-01

    Object of research is the help information resource "The chronicle of the Odessa national university of I. I. Mechnikov: dates, facts, events". The main objective of our article – to state the main methodological bases of creation of information resource. One of advantages of information resource is possibility of continuous updating and replenishment by new information. Main objective of creation of this information resource is systematization of material on stories of the Odessa national university of I. I. Mechnikov from the date of his basis to the present, ensuring interactive access to information on the main dates, the most significant events in life of university. The base of research are sources on the history of university, chronology of historical development, formation of infrastructure, cadres and scientific researches. In information resource the main stages of development, functioning and transformation of the Odessa University are analyzed, information on its divisions is collected. For creation of this information resource in Scientific library the method of work was developed, the main selection criteria of data are allocated. This information resource have practical value for all who is interested in history of university, historians, scientists-researchers of history of science and the city of Odessa.

  4. Print and Electronic Resources: Usage Statistics at Guru Gobind Singh Indraprastha University Library

    Science.gov (United States)

    Kapoor, Kanta

    2010-01-01

    Purpose: The purpose of this paper is to quantify the use of electronic journals in comparison with the print collections in the Guru Gobind Singh Indraprastha University Library. Design/methodology/approach: A detailed analysis was made of the use of lending services, the Xerox facility and usage of electronic journals such as Science Direct,…

  5. Understanding intention to use electronic information resources: A theoretical extension of the technology acceptance model (TAM).

    Science.gov (United States)

    Tao, Donghua

    2008-11-06

    This study extended the Technology Acceptance Model (TAM) by examining the roles of two aspects of e-resource characteristics, namely, information quality and system quality, in predicting public health students' intention to use e-resources for completing research paper assignments. Both focus groups and a questionnaire were used to collect data. Descriptive analysis, data screening, and Structural Equation Modeling (SEM) techniques were used for data analysis. The study found that perceived usefulness played a major role in determining students' intention to use e-resources. Perceived usefulness and perceived ease of use fully mediated the impact that information quality and system quality had on behavior intention. The research model enriches the existing technology acceptance literature by extending TAM. Representing two aspects of e-resource characteristics provides greater explanatory information for diagnosing problems of system design, development, and implementation.

  6. A shear-induced network of aligned wormlike micelles in a sugar-based molecular gel. From gelation to biocompatibility assays.

    Science.gov (United States)

    Fitremann, Juliette; Lonetti, Barbara; Fratini, Emiliano; Fabing, Isabelle; Payré, Bruno; Boulé, Christelle; Loubinoux, Isabelle; Vaysse, Laurence; Oriol, Luis

    2017-10-15

    A new low molecular weight hydrogelator with a saccharide (lactobionic) polar head linked by azide-alkyne click chemistry was prepared in three steps. It was obtained in high purity without chromatography, by phase separation and ultrafiltration of the aqueous gel. Gelation was not obtained reproducibly by conventional heating-cooling cycles and instead was obtained by shearing the aqueous solutions, from 2 wt% to 0.25 wt%. This method of preparation favored the formation of a quite unusual network of interconnected large but thin 2D-sheets (7nm-thick) formed by the association side-by-side of long and aligned 7nm diameter wormlike micelles. It was responsible for the reproducible gelation at the macroscopic scale. A second network made of helical fibres with a 10-13nm diameter, more or less intertwined was also formed but was scarcely able to sustain a macroscopic gel on its own. The gels were analysed by TEM (Transmission Electronic Microscopy), cryo-TEM and SAXS (Small Angle X-ray Scattering). Molecular modelling was also used to highlight the possible conformations the hydrogelator can take. The gels displayed a weak and reversible transition near 20°C, close to room temperature, ascribed to the wormlike micelles 2D-sheets network. Heating over 30°C led to the loss of the gel macroscopic integrity, but gel fragments were still observed in suspension. A second transition near 50°C, ascribed to the network of helical fibres, finally dissolved completely these fragments. The gels showed thixotropic behaviour, recovering slowly their initial elastic modulus, in few hours, after injection through a needle. Stable gels were tested as scaffold for neural cell line culture, showing a reduced biocompatibility. This new gelator is a clear illustration of how controlling the pathway was critical for gel formation and how a new kind of self-assembly was obtained by shearing. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Effect of the molecular weight of a neutral polysaccharide on soy protein gelation.

    Science.gov (United States)

    Monteiro, Sónia R; Lopes-da-Silva, José A

    2017-12-01

    The effects of galactomannans with different molecular weights on the heat-induced gelation characteristics of soybean protein were investigated using dynamic small-strain rheometry, under conditions where the proteins carry a net negative charge (pH7). Microstructure of the resulting gels was investigated by confocal laser scanning microscopy. Phase-separated systems were obtained with different morphologies and degree of phase separation, depending on both biopolymer concentrations and polysaccharide molecular weight. In general, a gelling enhancing effect on soy proteins was verified, despite extensive phase-separation processes observed at the higher polysaccharide molecular weight. This effect was demonstrated by an increase of the gelation rate, a decrease in the temperature at the onset of gelation, and an increase of gel stiffness and elastic character, with the length of polysaccharide chains. Overall, the results obtained established that the judicious selection of the galactomannan molecular weight may be used to modify the structure and gelation properties of soy proteins, originating a diversity of rheological characteristics and microstructures that will impact on the design of novel food formulations. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Solvent-mediated pathways to gelation and phase separation in suspensions of grafted nanoparticles

    KAUST Repository

    Anyfantakis, Manos

    2009-01-01

    We explore the role of the solvent medium on the interplay between gelation and phase separation in suspensions of organosilicate planar hybrids grafted with hydrocarbon chains. We establish their phase diagram by means of dynamic light scattering, rheology and visual observations, and different routes to gelation, depending on the solvent used. In agreement with earlier works, the solvent quality for the grafted chains at a given temperature controls the balance between attractions and repulsions, and hence the phase diagram of the nanoparticles and their tendency to gel. Here we show how to tune the suspension state and hence its rheology. For decane, a good solvent for the hydrocarbon chains, gelation occurs at rather low volume fractions in the presence of phase separation. This is due to the interdigitation of solvent molecules with the grafted chains, resulting in their crystalline packing that promotes the attraction between particles. For toluene, a solvent of reduced quality for the hydrocarbon chains, no interdigitation takes place, and hence gelation is triggered by clustering at higher volume fractions before phase separation. Our results support the generic picture of complex kinetic arrest/phase separation interplay in soft matter, where phase separation can proceed, be interrupted or be completely inhibited. A number of interesting possibilities for tailoring the rheology of grafted colloidal systems emerge. © 2009 The Royal Society of Chemistry.

  9. Heat stability and acid gelation properties of calcium-enriched reconstituted skim milk affected by ultrasonication.

    Science.gov (United States)

    Chandrapala, Jayani; Bui, Don; Kentish, Sandra; Ashokkumar, Muthupandian

    2014-05-01

    The aggregation of proteins after heating of calcium-fortified milks has been an ongoing problem in the dairy industry. This undesirable effect restricts the manufacture of calcium rich dairy products. To overcome this problem, a completely new approach in controlling the heat stability of dairy protein solutions, developed in our lab, has been employed. In this approach, high intensity, low frequency ultrasound is applied for a very short duration after a pre-heating step at ⩾70 °C. The ultrasound breaks apart whey/whey and whey/casein aggregates through the process of acoustic cavitation. Protein aggregates do not reform on subsequent post-heating, thereby making the systems heat stable. In this paper, the acid gelation properties of ultrasonicated calcium-enriched skim milks have also been investigated. It is shown that ultrasonication alone does not change the gelation properties significantly whereas a sequence of preheating (72 °C/1 min) followed by ultrasonication leads to decreased gelation times, decreased gel syneresis and increased skim milk viscosity in comparison to heating alone. Overall, ultrasonication has the potential to provide calcium-fortified dairy products with increased heat stability. However, enhanced gelation properties can only be achieved when ultrasonication is completed in conjunction with heating.

  10. A saponification-triggered gelation of ester-based Zn(II) complex through conformational transformations.

    Science.gov (United States)

    Kumar, Ashish; Dubey, Mrigendra; Kumar, Amit; Pandey, Daya Shankar

    2014-09-11

    Novel saponification-triggered gelation in an ester-based bis-salen Zn(II) complex (1) is described. Strategic structural modifications induced by NaOH in 1 tune the dipolar-/π-interactions leading to J-aggregation and the creation of an inorganic gel material (IGM), which has been established by photophysical, DFT and rheological studies.

  11. KINETICS OF A SILICATE COMPOSITION GELATION IN PRESENCE OF REACTION RATE REGULATING COMPOUNDS

    Directory of Open Access Journals (Sweden)

    Olga Titova

    2013-12-01

    Full Text Available The influence of organic and inorganic additions on the formation rate of the silicate gels standard systems – sodium silicate solution in model fresh water was studied. As a result of the experiments were selected optimum concentrations of additives - gelation time regulators

  12. Controlling the aggregation and gelation of ß-lactoglobulin by the addition of its peptides

    NARCIS (Netherlands)

    Kosters, H.A.

    2012-01-01

    In this thesis the effects of peptides, or protein hydrolysates on the heat-induced aggregation and gelation of (concentrated) protein systems were studied. First, it was investigated if specific peptides could influence the heat-induced denaturation and aggregation of intact proteins solutions,

  13. Enzyme catalyzed oxidative gelation of sugar beet pectin: Kinetics and rheology

    DEFF Research Database (Denmark)

    Abang Zaidel, Dayang Norulfairuz; Chronakis, Ioannis S.; Meyer, Anne S.

    2012-01-01

    Sugar beet pectin (SBP) is a marginally utilized co-processing product from sugar production from sugar beets. In this study, the kinetics of oxidative gelation of SBP, taking place via enzyme catalyzed cross-linking of ferulic acid moieties (FA), was studied using small angle oscillatory...

  14. Production of cerium dioxide microspheres by an internal gelation sol–gel method

    Energy Technology Data Exchange (ETDEWEB)

    Katalenich, Jeffrey A.

    2017-03-27

    An internal gelation sol-gel technique was used to prepare cerium dioxide microspheres with uniform diameters near 100 µm. In this process, chilled aqueous solutions containing cerium, hexamethylenetetramine (HMTA), and urea are transformed into a solid gel by heat addition and are subsequently washed, dried, and sintered to produce pure cerium dioxide. Cerous nitrate and ceric ammonium nitrate solutions were compared for their usefulness in microsphere production. Gelation experiments were performed with both cerous nitrate and ceric ammonium nitrate to determine desirable concentrations of cerium, HMTA, and urea in feed solutions as well as the necessary quantity of ammonium hydroxide added to cerium solutions. Analysis of the pH before and after sample gelation was found to provide a quantitative metric for optimal parameter selection along with subjective evaluations of gel qualities. The time necessary for chilled solutions to gel upon inserting into a hot water bath was determined for samples with a variety of parameters and also used to determine desirable formulations for microsphere production. A technique for choosing the optimal mixture of ceric ammonium nitrate, HMTA, and urea was determined using gelation experiments and used to produce microspheres by dispersion of the feed solution into heated silicone oil. Gelled spheres were washed to remove excess reactants and reaction products before being dried and sintered. X-ray diffraction of air-dried microspheres, sintered microspheres, and commercial CeO2 powders indicated that air-dried and sintered spheres were pure CeO2.

  15. Building and Managing Electronic Resources in Digital Era in India with Special Reference to IUCAA and NIV, Pune: A Comparative Case Study

    Science.gov (United States)

    Sahu, H. K.; Singh, S. N.

    2015-04-01

    This paper discusses and presents a comparative case study of two libraries in Pune, India, Inter-University Centre for Astronomy and Astrophysics and Information Centre and Library of National Institute of Virology (Indian Council of Medical Research). It compares how both libraries have managed their e-resource collections, including acquisitions, subscriptions, and consortia arrangements, while also developing a collection of their own resources, including pre-prints and publications, video lectures, and other materials in an institutional repository. This study illustrates how difficult it is to manage electronic resources in a developing country like India, even though electronic resources are used more than print resources. Electronic resource management can be daunting, but with a systematic approach, various problems can be solved, and use of the materials will be enhanced.

  16. The level of the usage of the human resource information system and electronic recruitment in Croatian companies

    Directory of Open Access Journals (Sweden)

    Snježana Pivac

    2014-12-01

    Full Text Available Performing business according to contemporary requirements influences companies for continuous usage of modern managerial tools, such as a human resource information system (HRIS and electronic recruitment (ER. Human resources have been recognised as curtail resources and the main source of a competitive advantage in creation of successful business performance. In order to attract and select the top employees, companies use quality information software for attracting internal ones, and electronic recruitment for attracting the best possible external candidates. The main aim of this paper is to research the level of the usage of HRIS and ER within medium-size and large Croatian companies. Moreover, the additional aim of this paper is to evaluate the relationship among the usage of these modern managerial tools and the overall success of human resource management within these companies. For the purpose of this paper, primary and secondary research has been conducted in order to reveal the level of the usage of HRIS and ER as well as the overall success of human resource management in Croatian companies. The companies’ classification (HRIS and ER is done by using the non-hierarchical k-means cluster method as well as the nonparametric Kruskal Wallis test. Further, the companies are ranked by the multicriteria PROMETHEE method. Relevant nonparametric tests are used for testing the overall companies’ HRM. Finally, binary logistic regression is estimated, relating binary variable HRM and HRIS development. After detailed research, it can be concluded that large Croatian companies apply HRIS in majority (with a positive relation to HRM performance, but still require certain degrees of its development.

  17. MendelWeb: An Electronic Science/Math/History Resource for the WWW.

    Science.gov (United States)

    Blumberg, Roger B.

    This paper describes a hypermedia resource, called MendelWeb that integrates elementary biology, discrete mathematics, and the history of science. MendelWeb is constructed from Gregor Menders 1865 paper, "Experiments in Plant Hybridization". An English translation of Mendel's paper, which is considered to mark the birth of classical and…

  18. Helping Patrons Find Locally Held Electronic Resources: An Interlibrary Loan Perspective

    Science.gov (United States)

    Johnston, Pamela

    2016-01-01

    The University of North Texas Libraries provide extensive online access to academic journals through major vendor databases. As illustrated by interlibrary loan borrowing requests for items held in our databases, patrons often have difficulty navigating the available resources. In this study, the Interlibrary Loan staff used data gathered from the…

  19. QR Codes as Finding Aides: Linking Electronic and Print Library Resources

    Science.gov (United States)

    Kane, Danielle; Schneidewind, Jeff

    2011-01-01

    As part of a focused, methodical, and evaluative approach to emerging technologies, QR codes are one of many new technologies being used by the UC Irvine Libraries. QR codes provide simple connections between print and virtual resources. In summer 2010, a small task force began to investigate how QR codes could be used to provide information and…

  20. Eavesdropping on Electronic Guidebooks: Observing Learning Resources in Shared Listening Environments.

    Science.gov (United States)

    Woodruff, Allison; Aoki, Paul M.; Grinter, Rebecca E.; Hurst, Amy; Szymanski, Margaret H.; Thornton, James D.

    This paper describes an electronic guidebook, "Sotto Voce," that enables visitors to share audio information by eavesdropping on each others guidebook activity. The first section discusses the design and implementation of the guidebook device, key aspects of its user interface, the design goals for the audio environment, the eavesdropping…

  1. Development and evolution of The Knowledge Hub for Pathology and related electronic resources.

    Science.gov (United States)

    Hardwick, David F; Sinard, John; Silva, Fred

    2011-06-01

    The Knowledge Hub for Pathology was created to provide authenticated and validated knowledge for United States and Canadian Academy of Pathology members and pathologists worldwide with access to the Web. Using the material presented at the annual meeting of the United States and Canadian Academy of Pathology with existing selection and review procedures ensured that these criteria were met without added costly procedures. Further submissions for courses and research papers are provided in electronic format and funded by universities and hospitals for their creation; thus, the principal costs borne by the United States and Canadian Academy of Pathology are Web site-posting costs. Use has escalated rapidly from 2 million hits in 2002 to 51 million in 2009 with use by 35,000 pathologists from now a total of 180 countries. This true "freemium" model is a successful process as are more traditional continuing professional development course structures such as Anatomic Pathology Electronic Case Series, a "premium" model for learning electronically also sponsored by the United States and Canadian Academy of Pathology. Copyright © 2011 Elsevier Inc. All rights reserved.

  2. An Exploratory study on the use of LibAnswers to Resolve, Track and Monitor Electronic Resources Issues: The KAUST Library experience

    KAUST Repository

    Ramli, Rindra M.

    2017-01-01

    An Exploratory study on KAUST library use of LibAnswers in resolving electronic resources questions received in LibAnswers. It describes the findings of the questions received in LibAnswers. The author made suggestions based on the findings to improve the reference services in responding to e-resources questions.

  3. An Exploratory study on the use of LibAnswers to Resolve, Track and Monitor Electronic Resources Issues: The KAUST Library experience

    KAUST Repository

    Ramli, Rindra M.

    2017-05-03

    An Exploratory study on KAUST library use of LibAnswers in resolving electronic resources questions received in LibAnswers. It describes the findings of the questions received in LibAnswers. The author made suggestions based on the findings to improve the reference services in responding to e-resources questions.

  4. Designing a model of electronic human resource management’s implementation at the Ministry of Communications and Information Technology

    Directory of Open Access Journals (Sweden)

    Mirali Seyednaghavi

    2017-06-01

    Full Text Available : In the first phase of this study a model for electronic human resource management in government agencies based on new public services was explored by using software MAXQDA, then in the second phase, relationship between the elements of the theory were tested using software Smart PLS2. So the aim of this study is to design a model of electronic human resource management’s implementation at the Ministry of Communications and Information Technology. In this regard, according to Strauss and Corbin’s structured plan, five hypotheses were tested. Quantitative data analysis indicates that the pressures of the policies and global perspectives cause to move toward e-HRM. Among the contextual conditions macro structural mechanisms, considerations of actors, governance considerations have a significant impact on the strategy of new public services and therefore lead to the consequences of its implementation in public organizations. The findings suggest that e-HRM does not have a positive and meaningful impact on new public services, and in our country, although the recent political developments have somehow removed the gap between public policy makers, administrators, and the public, but there is still a long way to go.

  5. Preference and Use of Electronic Information and Resources by Blind/Visually Impaired in NCR Libraries in India

    Directory of Open Access Journals (Sweden)

    Shailendra Kumar

    2013-06-01

    Full Text Available This paper aims to determine the preference and use of electronic information and resources by blind/visually impaired users in the leading National Capital Region (NCR libraries of India. Survey methodology has been used as the basic research tool for data collection with the help of questionnaires. The 125 in total users surveyed in all the five libraries were selected randomly on the basis of willingness of the users with experience of working in digital environments to participate in the survey. The survey results were tabulated and analyzed with descriptive statistics methods using Excel software and 'Stata version 11'. The findings reveal that ICT have a positive impact in the lives of people with disabilities as it helps them to work independently and increases the level of confidence among them. The Internet is the most preferred medium of access to information among the majority of blind/visually impaired users. The 'Complexity of content available on the net' is found as the major challenge faced during Internet use by blind users of NCR libraries. 'Audio books on CDs/DVDs and DAISY books' are the most preferred electronic resources among the majority of blind/visually impaired users. This study will help the library professionals and organizations/institutions serving people with disabilities to develop effective library services for blind/visually impaired users in the digital environment on the basis of findings on information usage behavior in the study.

  6. Internet and electronic resources for inflammatory bowel disease: a primer for providers and patients.

    Science.gov (United States)

    Fortinsky, Kyle J; Fournier, Marc R; Benchimol, Eric I

    2012-06-01

    Patients with inflammatory bowel disease (IBD) are increasingly turning to the Internet to research their condition and engage in discourse on their experiences. This has resulted in new dynamics in the relationship between providers and their patients, with misinformation and advertising potentially presenting barriers to the cooperative patient-provider partnership. This article addresses important issues of online IBD-related health information and social media activity, such as quality, reliability, objectivity, and privacy. We reviewed the medical literature on the quality of online information provided to IBD patients, and summarized the most commonly accessed Websites related to IBD. We also assessed the activity on popular social media sites (such as Facebook, Twitter, and YouTube), and evaluated currently available applications for use by IBD patients and providers on mobile phones and tablets. Through our review of the literature and currently available resources, we developed a list of recommended online resources to strengthen patient participation in their care by providing reliable, comprehensive educational material. Copyright © 2011 Crohn's & Colitis Foundation of America, Inc.

  7. Peptide Drug Release Behavior from Biodegradable Temperature-Responsive Injectable Hydrogels Exhibiting Irreversible Gelation

    Directory of Open Access Journals (Sweden)

    Kazuyuki Takata

    2017-10-01

    Full Text Available We investigated the release behavior of glucagon-like peptide-1 (GLP-1 from a biodegradable injectable polymer (IP hydrogel. This hydrogel shows temperature-responsive irreversible gelation due to the covalent bond formation through a thiol-ene reaction. In vitro sustained release of GLP-1 from an irreversible IP formulation (F(P1/D+PA40 was observed compared with a reversible (physical gelation IP formulation (F(P1. Moreover, pharmaceutically active levels of GLP-1 were maintained in blood after subcutaneous injection of the irreversible IP formulation into rats. This system should be useful for the minimally invasive sustained drug release of peptide drugs and other water-soluble bioactive reagents.

  8. Factors influencing chymosin-induced gelation of milk from individual dairy cows

    DEFF Research Database (Denmark)

    Gustavsson, F.; Glantz, M; Buitenhuis, Albert Johannes

    2014-01-01

    the variation of gelation properties in this sample set. Non-coagulating milk was suggested to have lower ionic and total calcium content as well as lower relative concentrations of β-lactoglobulin than coagulating milk. The lower total calcium content in non-coagulating milk poses a problem as the difference...... calcium content, phosphorous content and casein micelle size on chymosin-induced gelation was determined in milk from 98 Swedish Red cows. The study showed that protein content and total calcium content, ionic calcium concentration and casein micelle size were the most important factors explaining...... was, theoretically, four times larger than the amount of calcium that is normally added in cheese processing...

  9. Pectin gelation with chlorhexidine: Physico-chemical studies in dilute solutions.

    Science.gov (United States)

    Lascol, Manon; Bourgeois, Sandrine; Guillière, Florence; Hangouët, Marie; Raffin, Guy; Marote, Pedro; Lantéri, Pierre; Bordes, Claire

    2016-10-05

    Low methoxyl pectin is known to gel with divalent cations (e.g. Ca(2+), Zn(2+)). In this study, a new way of pectin gelation in the presence of an active pharmaceutical ingredient, chlorhexidine (CX), was highlighted. Thus chlorhexidine interactions with pectin were investigated and compared with the well-known pectin/Ca(2+) binding model. Gelation mechanisms were studied by several physico-chemical methods such as zeta potential, viscosity, size measurements and binding isotherm was determined by Proton Nuclear Magnetic Resonance Spectroscopy ((1)H NMR). The binding process exhibited similar first two steps for both divalent ions: a stoichiometric monocomplexation of the polymer followed by a dimerization step. However, stronger interactions were observed between pectin and chlorhexidine. Moreover, the dimerization step occurred under stoichiometric conditions with chlorhexidine whereas non-stoichiometric conditions were involved with calcium ions. In the case of chlorhexidine, an additional intermolecular binding occurred in a third step. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Effects of nano-scaled fish bone on the gelation properties of Alaska pollock surimi.

    Science.gov (United States)

    Yin, Tao; Park, Jae W

    2014-05-01

    Gelation properties of Alaska pollock surimi as affected by addition of nano-scaled fish bone (NFB) at different levels (0%, 0.1%, 0.25%, 0.5%, 1% and 2%) were investigated. Breaking force and penetration distance of surimi gels after setting increased significantly as NFB concentration increased up to 1%. The first peak temperature and value of storage modulus (G'), which is known to relate to the unfolding and aggregation of light meromyosin, increased as NFB concentration increased. In addition, 1% NFB treatment demonstrated the highest G' after gelation was completed. The activity of endogenous transglutaminase (TGase) in Alaska pollock surimi increased as NFB calcium concentration increased. The intensity of myosin heavy chain cross-links also increased as NFB concentration increased indicating the formation of more ε-(γ-glutamyl) lysine covalent bond by endogenous TGase and calcium ions from NFB. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. Enhanced gelation of chitosan/β-sodium glycerophosphate thermosensitive hydrogel with sodium bicarbonate and biocompatibility evaluated.

    Science.gov (United States)

    Deng, Aipeng; Kang, Xi; Zhang, Jing; Yang, Yang; Yang, Shulin

    2017-09-01

    The application of chitosan/β-sodium glycerophosphate (β-GP) thermosensitive hydrogel has been limited by the relatively slow gelation, weak mechanical resistance and poor cytocompatibility. In this study, sodium hydrogen carbonate (NaHCO 3 ) was applied with β-GP as gel agents to produce high-strength hydrogel. The hydrogels prepared with high NaHCO 3 concentration or more gel agents showed shorter gelation time, better thermostability, drastically enhanced resistance in compression. Meanwhile, the hydrogels presented obvious porous structures and excellent biocompatibility to HUVEC and NIH 3T3 cultured in vitro with higher NaHCO 3 concentration and moderate concentration of β-GP. Overall, appropriate concentration of β-GP combined with NaHCO 3 can be a good gel regent to improve properties of chitosan thermosensitive hydrogels. Copyright © 2017 Elsevier B.V. All rights reserved.

  12. Time-oriented experimental design method to optimize hydrophilic matrix formulations with gelation kinetics and drug release profiles.

    Science.gov (United States)

    Shin, Sangmun; Choi, Du Hyung; Truong, Nguyen Khoa Viet; Kim, Nam Ah; Chu, Kyung Rok; Jeong, Seong Hoon

    2011-04-04

    A new experimental design methodology was developed by integrating the response surface methodology and the time series modeling. The major purposes were to identify significant factors in determining swelling and release rate from matrix tablets and their relative factor levels for optimizing the experimental responses. Properties of tablet swelling and drug release were assessed with ten factors and two default factors, a hydrophilic model drug (terazosin) and magnesium stearate, and compared with target values. The selected input control factors were arranged in a mixture simplex lattice design with 21 experimental runs. The obtained optimal settings for gelation were PEO, LH-11, Syloid, and Pharmacoat with weight ratios of 215.33 (88.50%), 5.68 (2.33%), 19.27 (7.92%), and 3.04 (1.25%), respectively. The optimal settings for drug release were PEO and citric acid with weight ratios of 191.99 (78.91%) and 51.32 (21.09%), respectively. Based on the results of matrix swelling and drug release, the optimal solutions, target values, and validation experiment results over time were similar and showed consistent patterns with very small biases. The experimental design methodology could be a very promising experimental design method to obtain maximum information with limited time and resources. It could also be very useful in formulation studies by providing a systematic and reliable screening method to characterize significant factors in the sustained release matrix tablet. Copyright © 2011 Elsevier B.V. All rights reserved.

  13. The Metal Effect on Self-Assembling of Oxalamide Gelators Explored by Mass Spectrometry and DFT Calculations

    Science.gov (United States)

    Dabić, Dario; Brkljačić, Lidija; Tandarić, Tana; Žinić, Mladen; Vianello, Robert; Frkanec, Leo; Kobetić, Renata

    2018-01-01

    Gels formed by self-assembly of small organic molecules are of wide interest as dynamic soft materials with numerous possible applications, especially in terms of nanotechnology for functional and responsive biomaterials, biosensors, and nanowires. Four bis-oxalamides were chosen to show if electrospray ionization mass spectrometry (ESI-MS) could be used as a prediction of a good gelator and also to shed light on the gelation processes. By inspecting the gelation of several solvent, we showed that bis(amino acid)oxalamide 1 proved to be the most efficient, also being able of forming the largest observable assemblies in the gas phase. The formation of singly charged assemblies holding from one up to six monomer units is the outcome of the strong intermolecular H-bonds, particularly among terminal carboxyl groups. The variation of solvents from polar aprotic towards polar protic did not have any significant effects on the size of the assemblies. The addition of a salt such as NaOAc or Mg(OAc)2, depending on the concentration, altered the assembling. Computational analysis at the DFT level aided in the interpretation of the observed trends and revealed that individual gelator molecules spontaneously assemble to higher aggregates, but the presence of the Na+ cation disrupts any gelator organization since it becomes significantly more favorable for gelator molecules to bind Na+ cations up to the 3:1 ratio than to self-assemble, being fully in line with experimental observations reported here. [Figure not available: see fulltext.

  14. Experimental Methodology for Determining Optimum Process Parameters for Production of Hydrous Metal Oxides by Internal Gelation

    Energy Technology Data Exchange (ETDEWEB)

    Collins, J.L.

    2005-10-28

    The objective of this report is to describe a simple but very useful experimental methodology that was used to determine optimum process parameters for preparing several hydrous metal-oxide gel spheres by the internal gelation process. The method is inexpensive and very effective in collection of key gel-forming data that are needed to prepare the hydrous metal-oxide microspheres of the best quality for a number of elements.

  15. Permanganate gel (PG) for groundwater remediation: compatibility, gelation, and release characteristics.

    Science.gov (United States)

    Lee, Eung Seok; Olson, Pamela R; Gupta, Neha; Solpuker, Utku; Schwartz, Franklin W; Kim, Yongje

    2014-02-01

    Permanganate (MnO4(-)) is a strong oxidant that is widely used for treating chlorinated ethylenes in groundwater. This study aims to develop hyper-saline MnO4(-) solution (MnO4(-) gel; PG) that can be injected into aquifers via wells, slowly gelates over time, and slowly release MnO4(-) to flowing water. In this study, compatibility and miscibility of gels, such as chitosan, aluminosilicate, silicate, and colloidal silica gels, with MnO4(-) were tested. Of these gels, chitosan was reactive with MnO4(-). Aluminosilicates were compatible but not readily miscible with MnO4(-). Silicates and colloidal silica were both compatible and miscible with MnO4(-), and gelated with addition of KMnO4 granules. Colloidal silica has low initial viscosity (<15cP), exhibited delayed gelation characteristics with the lag times ranging from 0 to 200min. Release of MnO4(-) from the colloidal silica-based PG gel occurred in a delayed fashion, with maximum duration of 24h. These results suggested that colloidal silica can be used to create PG or delayed-gelling forms containing other oxidants which can be used for groundwater remediation. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Factors influencing the gelation and rennetability of camel milk using camel chymosin

    DEFF Research Database (Denmark)

    Hailu, Yonas; Hansen, Egon Bech; Seifu, Eyassu

    2016-01-01

    The effects of temperature, pH, concentration of camel chymosin and addition of CaCl2 on the hydrolysis of κ-casein (κ-CN) and the coagulation kinetics of camel milk were investigated. The rate of κ-CN hydrolysis was higher at 40 °C than at 30 °C and with increasing addition of chymosin...... and decreasing pH. For all samples gelation was initiated at levels of camel milk κ-CN hydrolysis >95%. The gelation time (Tg) of camel milk was significantly reduced (from 717 to 526 s) at 30 °C when the concentration of chymosin was increased, but was independent of chymosin concentration at 40 °C. Reducing p......H also reduced Tg. The gel firmness increased at 40 °C (58 Pa) compared with 30 °C (44 Pa) and effect of CaCl2 addition on the gelation properties of camel milk was found to be dependent on pH; a significant improvement was only found at pH 6.3....

  17. Nozzleless Fabrication of Oil-Core Biopolymeric Microcapsules by the Interfacial Gelation of Pickering Emulsion Templates.

    Science.gov (United States)

    Leong, Jun-Yee; Tey, Beng-Ti; Tan, Chin-Ping; Chan, Eng-Seng

    2015-08-05

    Ionotropic gelation has been an attractive method for the fabrication of biopolymeric oil-core microcapsules due to its safe and mild processing conditions. However, the mandatory use of a nozzle system to form the microcapsules restricts the process scalability and the production of small microcapsules (microcapsules through ionotropic gelation at the interface of an O/W Pickering emulsion. This approach involves the self-assembly of calcium carbonate (CaCO3) nanoparticles at the interface of O/W emulsion droplets followed by the addition of a polyanionic biopolymer into the aqueous phase. Subsequently, CaCO3 nanoparticles are dissolved by pH reduction, thus liberating Ca(2+) ions to cross-link the surrounding polyanionic biopolymer to form a shell that encapsulates the oil droplet. We demonstrate the versatility of this method by fabricating microcapsules from different types of polyanionic biopolymers (i.e., alginate, pectin, and gellan gum) and water-immiscible liquid cores (i.e., palm olein, cyclohexane, dichloromethane, and toluene). In addition, small microcapsules with a mean size smaller than 100 μm can be produced by selecting the appropriate conventional emulsification methods available to prepare the Pickering emulsion. The simplicity and versatility of this method allows biopolymeric microcapsules to be fabricated with ease by ionotropic gelation for numerous applications.

  18. Electronic medical records in diabetes consultations: participants' gaze as an interactional resource.

    Science.gov (United States)

    Rhodes, Penny; Small, Neil; Rowley, Emma; Langdon, Mark; Ariss, Steven; Wright, John

    2008-09-01

    Two routine consultations in primary care diabetes clinics are compared using extracts from video recordings of interactions between nurses and patients. The consultations were chosen to present different styles of interaction, in which the nurse's gaze was either primarily toward the computer screen or directed more toward the patient. Using conversation analysis, the ways in which nurses shift both gaze and body orientation between the computer screen and patient to influence the style, pace, content, and structure of the consultation were investigated. By examining the effects of different levels of engagement between the electronic medical record and the embodied patient in the consultation room, we argue for the need to consider the contingent nature of the interface of technology and the person in the consultation. Policy initiatives designed to deliver what is considered best-evidenced practice are modified in the micro context of the interactions of the consultation.

  19. Granulometric composition study of mineral resources using opto-electronic devices and Elsieve software system

    Directory of Open Access Journals (Sweden)

    Kaminski Stanislaw

    2016-01-01

    Full Text Available The use of mechanical sieves has a great impact on measurement results because occurrence of anisometric particles causes undercounting the average size. Such errors can be avoided by using opto-electronic measuring devices that enable measurement of particles from 10 μm up to a few dozen millimetres in size. The results of measurement of each particle size fraction are summed up proportionally to its weight with the use of Elsieve software system and for every type of material particle-size distribution can be obtained. The software allows further statistical interpretation of the results. Beam of infrared radiation identifies size of particles and counts them precisely. Every particle is represented by an electronic impulse proportional to its size. Measurement of particles in aqueous suspension that replaces the hydrometer method can be carried out by using the IPS L analyser (range from 0.2 to 600 μm. The IPS UA analyser (range from 0.5 to 2000 μm is designed for measurement in the air. An ultrasonic adapter enables performing measurements of moist and aggregated particles from 0.5 to 1000 μm. The construction and software system allow to determine second dimension of the particle, its shape coefficient and specific surface area. The AWK 3D analyser (range from 0.2 to 31.5 mm is devoted to measurement of various powdery materials with subsequent determination of particle shape. The AWK B analyser (range from 1 to 130 mm measures materials of thick granulation and shape of the grains. The presented method of measurement repeatedly accelerates and facilitates study of granulometric composition.

  20. Encapsulating betalains from Opuntia ficus-indica fruits by ionic gelation: Pigment chemical stability during storage of beads.

    Science.gov (United States)

    Otálora, María Carolina; Carriazo, José Gregorio; Iturriaga, Laura; Osorio, Coralia; Nazareno, Mónica Azucena

    2016-07-01

    Betalain encapsulation was performed by ionic gelation as a stabilization strategy for these natural pigments. Betalains were extracted from purple cactus fruits and encapsulated in calcium-alginate and in combination of calcium alginate and bovine serum albumin. Beads were characterised by scanning electron microscopy and thermal analysis using differential scanning calorimetry and thermogravimetry. Moisture sorption isotherms were determined. Bead morphology was affected by matrix composition. Pigments storage stability was evaluated at different equilibrium relative humidity and temperatures. Pigment composition of beads was determined by HPLC-MS-MS and degradation products were also analysed after storage; betalamic acid being the major one. Both types of matrices protected the encapsulated pigments, being their storage stability better at low relative humidity than that of the non-encapsulated control material. Antiradical activities of beads were proportional to remaining betalain contents. At high relative humidity, there was no protection and low storage stability was observed in the samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

  1. Silica-gel structural characterization during the initial phases of gelation and drying

    International Nuclear Information System (INIS)

    Ferreira, Max Passos

    1996-01-01

    For centuries, glasses and ceramics have been made via melting or solid state reactions at temperatures above 100 deg C. The sol-gel process offers new approaches to the synthesis of glasses and ceramics, combining control of composition and structure at the molecular level with the ability to shape materials in bulk, powder, fiber and thin-film forms. The growth of sol-gel technology research is due to the many unique features of that class of materials. Major applications include optical elements and integrated optical devices, ceramic filters, membranes, supercondutors, magnetic, catalytic and manostructured materials to antioxidant, anticorrosion coatings and composite and biomedical materials. In this work a variety of techniques like spectroscopy, Raman spectroscopy, ultraviolet-visible spectroscopy, light scattering nuclear magnetic resonance, X ray diffraction and nitrogen adsorption have been employed to investigate the initial phase of the sol-gel transition of gamma ray irradiated tetramethoxysilane (TMOS) solutions and non-irradiated TMOS solution and to get information about the structure of the silica gels obtained under different gelation conditions. Typically the tetramethoxysilane solutions were prepared using a molar ratio of TMOS to demineralized water of 1 to 16. Some experiments were made under catalysed conditions. The mixing was carried out at room temperature. The turbidity and light scattering experiments on the polycondensation of tetramethoxysilane show that exists no drastic difference in the gelling time of a gamma ray irradiated and a non-irradiated TMOS+H 2 O (1+16 M) solution. In the absence of a catalyst, the gelling time for both reactions occurs in about 3.30 h. When HNO 3 (o.03 M) was used, the gelling time observed was 3 days. Raman and ultraviolet-visible spectroscopy show no drastic difference during the initial phase at the sol-gel transition under ambient temperature/pressure and under gamma radiation. The gels heated

  2. Universal sol state behavior and gelation kinetics in mixed clay dispersions.

    Science.gov (United States)

    Pujala, Ravi Kumar; Pawar, Nisha; Bohidar, H B

    2011-05-03

    Sol and gel state behavior, in aqueous salt free dispersions, of clays Laponite (L) and Na montmorillonite (MMT) was studied at various mixing ratios (L:MMT = r = 1:0.5, 1:1, and 1:2). In the sol state, the zeta potential and gelation concentration of L-MMT obeyed the universal relation, X(L-MMT) = (rX(L) + X(MMT))/(1 + r), where X is zeta potential or gelation concentration (c(g)), implying that these properties are linear combinations of the same of their individual components. The low frequency storage modulus (G(0)'), relative viscosity (η(r)), and apparent cluster size (R) could be universally described by the power-law, G(0)' ∼ ((c/c(g)) - 1)(t) (c > c(g)), and η(r), R ∼ (1 - (c/c(g)))(-k,ν) (c < c(g)), with t = 1.5, k = 1.1, and υ = 0.8 close to the gelation concentration, for r = 1:1 cogel, consistent with the percolation model description of gelation. Interestingly, the hyperscaling relation δ = t/(k + t) yielded δ = 0.56 not too different from the predicted value ∼0.7, while the experimental value of δ obtained from G''(ω) ∼ ω(δ) close to c ≈ c(g) yielded δ = 1.5, which was at variance with the hyperscaling result. The experimental data, on hand, mostly supported percolation type gelation mechanism. As the cogels were slowly heated, at a characteristic temperature, T(g), a sharp increase in G' value was noticed, implying a transition to gel hardening (a new phase state). The temperature-dependent behavior followed the power-law description, G' ∼ (T(g) - T)(-γ) (T < T(g)), with γ = 0.40 ± 0.05 invariant of composition of the cogel, whereas for MMT and Laponite, γ = 0.25 and 0.55, respectively. It has been shown that the cogel has significantly enhanced mechanical (G(0) increased by 10 times for r = 1:1 cogel) and thermal properties (T(g) increased by 13 °C for 1:1 cogel) that can be exploited to design customized soft materials.

  3. Green Supply Chain Collaboration for Fashionable Consumer Electronics Products under Third-Party Power Intervention—A Resource Dependence Perspective

    Directory of Open Access Journals (Sweden)

    Jiuh-Biing Sheu

    2014-05-01

    Full Text Available Under third-party power intervention (TPPI, which increases uncertainty in task environments, complex channel power interplays and restructuring are indispensable among green supply chain members as they move toward sustainable collaborative relationships for increased viability and competitive advantage. From the resource dependence perspective, this work presents a novel conceptual model to investigate the influence of political and social power on channel power restructuring and induced green supply chain collaboration in brander-retailer bidirectional green supply chains of fashionable consumer electronics products (FCEPs. An FCEP refers to the consumer electronics product (e.g., personal computers, mobile phones, computer notebooks, and game consoles with the features of a well-known brand associated, a short product lifecycle, timely and fashionable design fit for market trends, and quick responsiveness to the variations of market demands. The proposed model is tested empirically using questionnaire data obtained from retailers in the FCEP brander-retailer distribution channels. Analytical results reveal that as an extension of political and social power, TPPI positively affects the reciprocal interdependence of dyadic members and reduces power asymmetry, thereby enhancing the collaborative relationship of dyadic members and leading to improved green supply chain performance. Therein, reciprocal interdependence underlying collaborative relationship is the key to reducing the external environmental uncertainties in the TPPI context.

  4. The management of online resources and long-term saving of electronic documents by transfer into the digital space

    Directory of Open Access Journals (Sweden)

    Marius Daniel MAREŞ

    2011-12-01

    The electronic archive refers to the electronic storage system, along with the totality of electronic-type stored documents, while using as storage support any environment that can support storing and from which an electronic document can be presented.

  5. Solubilization of bovine gelatin using power ultrasound: gelation without heating.

    Science.gov (United States)

    Farahnaky, Asgar; Zendeboodi, Fatemeh; Azizi, Rezvan; Mesbahi, Gholamreza; Majzoobi, Mahsa

    2017-04-01

    The aim of this study was to investigate the efficacy of power ultrasound without using any heating stage in solubilizeing gelatin dispersions, and to characterize the mechanical and microstructural properties of the resulting gels using texture analysis and scanning electron microscopy, respectively. Usually to prepare a gel from gelatin, a primary heating stage of at about 40C or above is required to solubilize gelatin macromolecules. In this study solubilizing gelatin dispersions using power ultrasound without any heating was successfully performed. For solubilising gelatin, an ultrasound equipment with a frequency of 20 kHz, amplitude of 100% and power range of 50-150 W was used. Aqueous gelatin dispersions (4% w/v) were subjected to ultrasound for different times (40-240 s) at a constant temperature of 13C. Applying ultrasound to gelatin dispersions caused increases in water absorption and water solubility of the hydrocolloid. The textural parameters of the resulting gelatin gels, increased with increasing time and power of ultrasound. Moreover, a generalized Maxwell model with three elements was used for calculating relaxation times of the gels. The microstructural observations by SEM showed that the structural cohesiveness of the gels increased by increasing ultrasonication time. Ultrasound-assisted solubilization of gelatin can have emerging implications for industrial uses in pharmaceuticals, food and non-food systems. Usually to prepare a gel from gelatin, a primary heating stage of at about 40C or above is required to solubilize gelatin macromolecules. Therefore, the use of gelatin as a hydrocolloid in food processings or pharmaceutical formulations which lack a heating step has been a technological and practical challenge. In this study solubilizing gelatin dispersions using power ultrasound without any heating was successfully performed. Ultrasound-assisted solubilisation of gelatin can have emerging implications for industrial uses in pharmaceuticals

  6. Influence of pre-cooking protein paste gelation conditions and post-cooking gel storage conditions on gel texture.

    Science.gov (United States)

    Paker, Ilgin; Matak, Kristen E

    2016-01-15

    Gelation conditions affect the setting of myofibrillar fish protein gels. Therefore the impact of widely applied pre-cooking gelation time/temperature strategies and post-cooking period on the texture and color of final protein gels was determined. Four pre-cooking gelation strategies (no setting time, 30 min at 25 °C, 1 h at 40 °C or 24 h at 4 °C) were applied to protein pastes (fish protein concentrate and standard functional additives). After cooking, texture and color were analyzed either directly or after 24 h at 4 °C on gels adjusted to 25 °C. No-set gels were harder, gummier and chewier (P cooking. Gel-setting conditions had a greater (P cooking stored gels in texture and color, depending on the pre-cooking gelation strategy. Pre-cooking gelation conditions will affect final protein gel texture and color, with gel stability benefiting from a gel-setting period. However, post-cooking storage may have a greater impact on final gels, with textural attributes becoming more consistent between all samples. © 2015 Society of Chemical Industry.

  7. LABORATORY-SCALE PRODUCTION OF ADU GELS BY EXTERNAL GELATION FOR AN INTERMEDIATE HTGR NUCLEAR

    Directory of Open Access Journals (Sweden)

    S Simbolon

    2015-03-01

    Full Text Available LABORATORY-SCALE PRODUCTION OF ADU GELS BY EXTERNAL GELATION FOR AN INTERMEDIATE HTGR NUCLEAR. The The aim of this research is to produce thousands of microsphere ADU (Ammonium Diuranate gels by using external gelation for an intermediate HTGR (High Temperature Gas-cooled Reactor nuclear fuel in laboratory-scale. Microsphere ADU gels were based on sol-solution which was made from a homogeneous mixture of ADUN (Acid Deficient Uranyl Nitrate which was containing uranyl ion in high concentration, a water soluble organic compound PVA (Polyvinyl Alcohol and THFA (Tetrahydrofurfuryl Alcohol. The simple unified home made laboratory experimental machine was developed to replace test tube experiment method which was once used due to a tiny amount of microsphere ADU gels produced. It consists of four main parts: tank filled sol-solution connecting to peristaltic pump and vibrating nozzle, preliminary gelation and gelation column. The machine has successfully converted 150 mL sol-solution into thousands of drops which produced 120 - 130 drops in each minute in steady state in ammonia gas free sector. Preliminary gelation reaction was carried out in ammonia gas sector where drops react with ammonia gas in a bat an eye followed by gelation reaction in column containing ammonia solution 7 M. In ageing process, ADU gels were collected and submerged into a vessel containing ammonia solution which was shaken for 1 hour in a shaker device. Isopropyl alcohol (90% solution was used to wash ADU gels and a digital camera was used to measured spherical form of ADU gels. Diameters in spherical spheroid form were found between 1.8 mm until 2.2 mm. The spherical purity of ADU gels were 10% - 20% others were oblate, prolate spheroid and microsphere which have hugetiny of dimples on the surface.   PRODUKSI GEL ADU SKALA LABORATORIUM DENGAN MENGGUNAKAN GELASI EKSTERNAL UNTUK BAHAN BAKAR ANTARA HTGR. Penelitian ini bertujuan untuk membuat ribuan gel bulat ADU (Ammonium

  8. Effect of protease inhibitors on thermal gelation of squid (Illex argentinus. mantle paste

    Directory of Open Access Journals (Sweden)

    Maria Elida Paredi

    2014-04-01

    Full Text Available The characteristics of the thermal gelation of squid mantle paste and the effect of protease inhibitors on them were investigated. Pastes in the absence and presence the protease inhibitors, ethylendiaminetetracetic acid (EDTA and phenylmethylsulfonyl fluoride (PMSF, were formulated. Pastes were made by the respective one or two step thermal treatments: direct heating at 85°C for 20 min and preincubation at 27 or 40 °C for 3 or 2 hours, followed by heating at 85 °C for 20 min. The gel strength, water holding capacity (WHC and whiteness of gelled pastes were analyzed. The tricloroacetic acid (TCA soluble peptides in homogenate of the muscle were determined. Gel strength decreased when heating was made in two steps. EDTA and PMSF were effective in avoiding that decrease when pre-incubation was made at 40 °C. Maximum gel strength was observed for the gels in presence of EDTA, giving values of 255 and 219 g x cm for the samples made by direct heating and pre-incubated at 40 °C  respectively. TCA soluble peptides increased between 20 and 60 °C, with maximum values reached at 30 and 60 °C. No significant differences (p>0.05 were observed in gel whiteness, neither with the thermal treatment nor with the inhibitors. The WHC was higher (p<0.05 in the gelated paste formulated with EDTA. These results show a good gelation capacity of I argentinus pastes and improvements with protease inhibitors. 

  9. Investigation of small scale sphere-pac fuel fabrication plant with external gelation process

    International Nuclear Information System (INIS)

    Maekawa, Kazuhiko; Yoshimura, Tadahiro; Kikuchi, Toshiaki; Hoshino, Yasushi; Munekata, Hideki; Shimizu, Makoto

    2005-02-01

    In feasibility studies on commercialized FBR cycle system, comprehensive system investigation and properties evaluation for candidate FBR cycle systems have been implemented through view point of safety, economics, environmental burden reduction, non-proliferation resistivity, etc. As part of these studies, an investigation of small scale sphere-pac fuel fabrication plant with external gelation process was conducted. Until last fiscal year, equipment layout in cells and overall layout design of the 200t-HM/y scale fuel fabrication plant were conducted as well as schematical design studies on main equipments in gelation and reagent recovery processes of the plant. System property data concerning economics and environmental burden reduction of fuel fabrication plant was also acquired. In this fiscal year, the processes from vibropacking to fuel assemblies storage were added to the investigation range, and a conceptual design of whole fuel fabrication plant was studied as well as deepening the design study on main equipments. The conceptual design study was mainly conducted for small 50t-HM/y scale plant and a revising investigation was done for 200t-HM/y scale plant. Taking the planed comparative evaluation with pellet fuel fabrication system into account, design of equipments which should be equivalent with pellet system, especially in post-vibropacking processes, were standardized in each system. Based on these design studies, system properties data concerning economics and environmental burden reduction of the plant was also acquired. In comparison with existing design, the cell height was lowered on condition that plug type pneumatic system was adopted and fuel fabrication building was downsized by applying rationalized layout design of pellet system to post-vibropacking processes. Reduction of reagent usage at gelation process and rationalization of sintering and O/M controlling processes etc., are foremost tasks. (author)

  10. Development of an Electronic Medical Record Based Alert for Risk of HIV Treatment Failure in a Low-Resource Setting

    Science.gov (United States)

    Puttkammer, Nancy; Zeliadt, Steven; Balan, Jean Gabriel; Baseman, Janet; Destiné, Rodney; Domerçant, Jean Wysler; France, Garilus; Hyppolite, Nathaelf; Pelletier, Valérie; Raphael, Nernst Atwood; Sherr, Kenneth; Yuhas, Krista; Barnhart, Scott

    2014-01-01

    Background The adoption of electronic medical record systems in resource-limited settings can help clinicians monitor patients' adherence to HIV antiretroviral therapy (ART) and identify patients at risk of future ART failure, allowing resources to be targeted to those most at risk. Methods Among adult patients enrolled on ART from 2005–2013 at two large, public-sector hospitals in Haiti, ART failure was assessed after 6–12 months on treatment, based on the World Health Organization's immunologic and clinical criteria. We identified models for predicting ART failure based on ART adherence measures and other patient characteristics. We assessed performance of candidate models using area under the receiver operating curve, and validated results using a randomly-split data sample. The selected prediction model was used to generate a risk score, and its ability to differentiate ART failure risk over a 42-month follow-up period was tested using stratified Kaplan Meier survival curves. Results Among 923 patients with CD4 results available during the period 6–12 months after ART initiation, 196 (21.2%) met ART failure criteria. The pharmacy-based proportion of days covered (PDC) measure performed best among five possible ART adherence measures at predicting ART failure. Average PDC during the first 6 months on ART was 79.0% among cases of ART failure and 88.6% among cases of non-failure (pART initiation were added to PDC, the risk score differentiated between those who did and did not meet failure criteria over 42 months following ART initiation. Conclusions Pharmacy data are most useful for new ART adherence alerts within iSanté. Such alerts offer potential to help clinicians identify patients at high risk of ART failure so that they can be targeted with adherence support interventions, before ART failure occurs. PMID:25390044

  11. Development of an electronic medical record based alert for risk of HIV treatment failure in a low-resource setting.

    Directory of Open Access Journals (Sweden)

    Nancy Puttkammer

    Full Text Available The adoption of electronic medical record systems in resource-limited settings can help clinicians monitor patients' adherence to HIV antiretroviral therapy (ART and identify patients at risk of future ART failure, allowing resources to be targeted to those most at risk.Among adult patients enrolled on ART from 2005-2013 at two large, public-sector hospitals in Haiti, ART failure was assessed after 6-12 months on treatment, based on the World Health Organization's immunologic and clinical criteria. We identified models for predicting ART failure based on ART adherence measures and other patient characteristics. We assessed performance of candidate models using area under the receiver operating curve, and validated results using a randomly-split data sample. The selected prediction model was used to generate a risk score, and its ability to differentiate ART failure risk over a 42-month follow-up period was tested using stratified Kaplan Meier survival curves.Among 923 patients with CD4 results available during the period 6-12 months after ART initiation, 196 (21.2% met ART failure criteria. The pharmacy-based proportion of days covered (PDC measure performed best among five possible ART adherence measures at predicting ART failure. Average PDC during the first 6 months on ART was 79.0% among cases of ART failure and 88.6% among cases of non-failure (p<0.01. When additional information including sex, baseline CD4, and duration of enrollment in HIV care prior to ART initiation were added to PDC, the risk score differentiated between those who did and did not meet failure criteria over 42 months following ART initiation.Pharmacy data are most useful for new ART adherence alerts within iSanté. Such alerts offer potential to help clinicians identify patients at high risk of ART failure so that they can be targeted with adherence support interventions, before ART failure occurs.

  12. Synthesis and characterization of sugar based low molecular weight gelators and the preparation of chiral sulfinamides

    Science.gov (United States)

    Mangunuru, Hari Prasad Reddy

    Low molecular weight gelators (LMWGs) have received considerable attention in the field of chemistry from last few decades. These compounds form self-assembled fibrous networks like micelles, cylindrical, sheets, fibers, layers and so on. The fibrous network entraps the solvent and forms gel, because of the self-assembly phenomenon and their demonstrated potential uses in a variety of areas, ranging from environmental to medicinal applications. Sugars are good starting materials to synthesize the new class of LMWG's, because these are different from some expensive materials, these are natural products. We have synthesized and characterized the LMGS's based on D-glucose and D-glucosamine. D-glucosamine is the versatile starting material to make different peptoids and triazoles. Several series of compounds were synthesized using compounds 1-3 as starting material and studied the gelation behavior all the compounds. We have studied the self-assembling properties of a new class of tripeptoids, synthesized by one-pot Ugi reaction from simple starting materials. Among the focused library of tripeptoids synthesized, we found that several efficient low molecular weight organogelators were obtained for aqueous DMSO and ethanol mixtures. We have also synthesized and characterized a series of monosaccharide triazole derivatives. These compounds were synthesized from N-acetyl glucosamine and D-glucose via a Cu(I) catalyzed azide/alkyne cycloaddition reaction (CuAAc). The compounds have been screened for their gelation properties and several efficient low molecular weight organo/hydro gelators were obtained, among these compounds, five per-acetyl glucosamine derivatives and one peracetyl glucose derivative were able to form gels in water. These new molecules are expected to be useful in drug delivery and tissue engineering.*. Asymmetric synthesis of chiral amines is a challenging in synthetic organic chemistry. The development of new catalysts for asymmetric organic

  13. Pinning of phase separation of aqueous solution of hydroxypropylmethylcellulose by gelation

    Science.gov (United States)

    Kita, Rio; Kaku, Takeshi; Kubota, Kenji; Dobashi, Toshiaki

    1999-08-01

    Opalescence of the aqueous solution of hydroxypropylmethylcellulose (HPMC) induced by heating has been studied in terms of the phase diagram and the phase separation dynamics. The cloud point curve and the sol-to-gel transition curve intersected with each other at about 55 °C. Just above the cloud-point curve at which the spinodal curve has its minimum, a ring-like scattering pattern appeared corresponding to the spinodal decomposition. Temporal growth of the scattering function in the course of phase separation was studied by a time-resolved light scattering technique. The gelation pinned the phase separation (spinodal decomposition) of the aqueous HPMC solution.

  14. Rheological and gelation properties of rice starch modified with 4-alpha-glucanotransferase.

    Science.gov (United States)

    Lee, Kwang Yeon; Kim, Yong-Ro; Park, Kwan Hwa; Lee, Hyeon Gyu

    2008-04-01

    Rheological measurements were performed to characterize rice starch modified with 4-alpha-glucanotransferase (4alphaGTase) isolated from Thermus scotoductus, in terms of effects of the enzyme and starch concentration on flow behavior, gel strength, and melting and gelling kinetics of the modified rice starch. Consistency index decreased and flow behavior index increased with the level of enzyme treatment, and at high level of enzyme treatment, it demonstrated Bingham plastic behavior. As the level of enzyme decreased and the starch concentration increased, gelation time decreased and the final gel strength increased significantly. Regardless of treatment variables, all the modified starch gels melted at similar temperature.

  15. Innovative direct energy conversion systems using electronic adiabatic processes of electron fluid in solid conductors: new plants of electrical power and hydrogen gas resources without environmental pollutions

    International Nuclear Information System (INIS)

    Kondoh, Y.; Kondo, M.; Shimoda, K.; Takahashi, T.

    2001-07-01

    It is shown that using a novel recycling process of the environmental thermal energy, innovative permanent auto-working direct energy converter systems (PA-DEC systems) from the environmental thermal to electrical and/or chemical potential (TE/CP) energies, abbreviated as PA-TE/CP-DEC systems, can be used for new auto-working electrical power plants and the plants of the compressible and conveyable hydrogen gas resources at various regions in the whole world, with contributions to the world peace and the economical development in the south part of the world. It is shown that the same physical mechanism by free electrons and electrical potential determined by temperature in conductors, which include semiconductors, leads to the Peltier effect and the Seebeck one. It is experimentally clarified that the long distance separation between two π type elements of the heat absorption (HAS) and the production one (HPS) of the Peltier effect circuit system or between the higher temperature side (HTS) and the lower one (LTS) of the Seebeck effect circuit one does not change in the whole for the both effects. By using present systems, we do not need to use petrified fuels such as coals, oils, and natural gases in order to decrease the greenhouse effect by the CO 2 surrounding the earth. Furthermore, we do not need plats of nuclear fissions that left radiating wastes, i.e., with no environmental pollutions. The PA-TE/CP-DEC systems can be applicable for several km scale systems to the micro ones, such as the plants of the electrical power, the compact transportable hydrogen gas resources, a large heat energy container, which can be settled at far place from thermal energy absorbing area, the refrigerators, the air conditioners, home electrical apparatuses, and further the computer elements. It is shown that the simplest PA-TE/CP-DEC system can be established by using only the Seebeck effect components and the resolving water ones. It is clarified that the externally applied

  16. Preparation of ThO2 sols suitable for gelation into microspheres in CCl4-ammonia media

    International Nuclear Information System (INIS)

    Yamagishi, Shigeru; Takahashi, Yoshihisa

    1985-01-01

    Production conditions of ThO 2 sols are studied for satisfactorily gelling them into microspheres in CCl 4 -ammonia media, which result gel-spheres with good sphericities but need high-quality source-sols for crackfree gelation. Two-stage pH-setting techniques were added to the previously reported method, which had been developed to produce ThO 2 sols suitable for gelation in hexone-ammonia media and was characterized by preneutralization followed by neutralization under pH-control. As a result, colloid fractions of Th in sols were increased without decreasing colloid size. This enabled one to obtain crackfree, large, spherical ThO 2 particles by gelation in the CCl 4 -ammonia media. (author)

  17. Preparation of ThO2 sols having colloid-size distributions suitable for gelation into microspheres

    International Nuclear Information System (INIS)

    Yamagishi, Shigeru; Takahashi, Yoshihisa; Shiba, Koreyuki

    1984-01-01

    Production conditions of ThO 2 sols suitable for gelling into crackfree microspheres in an external gelation process were studied. The sols were prepared under pH control and colloid size distributions of the resulting sols were determined. The gelation was carried out by using hexone as a drop formation medium and ammonia as a gelling agent. The crackfree gelation was achieved by the use of ThO 2 sols produced under favorable pH, which were large in colloid size and high in colloid fraction. ''Preneutralization'' preceding the pH control is also important for the good sols. Analyzing the colloid fraction, colloid size and crystallite size of sol, it was found that, under the favorable pH, colloid nuclei generating at early stages grow in the form of single-crystals with their number kept constant and, after cooling, they exist as polycrystalline colloids. The mechanism of cracking is also discussed. (author)

  18. Determination of Ideal Broth Formulations Needed to Prepare Hydrous Cerium Oxide Microspheres via the Internal Gelation Process

    Energy Technology Data Exchange (ETDEWEB)

    Collins, Jack Lee [ORNL; Chi, Anthony [ORNL

    2009-02-01

    A simple test tube methodology was used to determine optimum process parameters for preparing hydrous cerium oxide microspheres via the internal gelation process.1 Broth formulations of cerium ammonium nitrate [(NH4)2Ce(NO3)6], hexamethylenetetramine, and urea were found that can be used to prepare hydrous cerium oxide gel spheres in the temperature range of 60 to 90 C. A few gel-forming runs were made in which microspheres were prepared with some of these formulations to be able to equate the test-tube gelation times to actual gelation times. These preparations confirmed that the test-tube methodology is reliable for determining the ideal broth formulations.

  19. Consumer reports [electronic resource

    National Research Council Canada - National Science Library

    1942-01-01

    ... only. A limited number of selected reports, advice on product selection and safety alerts are freely available, as are a five year listing of product recalls, a listing of major consumer product...

  20. The electronic Rothamsted Archive (e-RA), an online resource for data from the Rothamsted long-term experiments.

    Science.gov (United States)

    Perryman, Sarah A M; Castells-Brooke, Nathalie I D; Glendining, Margaret J; Goulding, Keith W T; Hawkesford, Malcolm J; Macdonald, Andy J; Ostler, Richard J; Poulton, Paul R; Rawlings, Christopher J; Scott, Tony; Verrier, Paul J

    2018-05-15

    The electronic Rothamsted Archive, e-RA (www.era.rothamsted.ac.uk) provides a permanent managed database to both securely store and disseminate data from Rothamsted Research's long-term field experiments (since 1843) and meteorological stations (since 1853). Both historical and contemporary data are made available via this online database which provides the scientific community with access to a unique continuous record of agricultural experiments and weather measured since the mid-19 th century. Qualitative information, such as treatment and management practices, plans and soil information, accompanies the data and are made available on the e-RA website. e-RA was released externally to the wider scientific community in 2013 and this paper describes its development, content, curation and the access process for data users. Case studies illustrate the diverse applications of the data, including its original intended purposes and recent unforeseen applications. Usage monitoring demonstrates the data are of increasing interest. Future developments, including adopting FAIR data principles, are proposed as the resource is increasingly recognised as a unique archive of data relevant to sustainable agriculture, agroecology and the environment.

  1. Effect of Sol Concentration, Aging and Drying Process on Cerium Stabilization Zirconium Gel Produced by External Gelation

    Science.gov (United States)

    Sukarsono, R.; Rachmawati, M.; Susilowati, S. R.; Husnurrofiq, D.; Nurwidyaningrum, K.; Dewi, A. K.

    2018-02-01

    Cerium Stabilized Zirconium gel has been prepared using external gelation process. As the raw materials was used ZrO(NO3)2 and Ce(NO3)4 nitrate salt which was dissolved with water into Zr-Ce nitrate mixture. The concentration of the nitrate salt mixture in the sol solution was varied by varying the concentration of zirconium and cerium nitrate in the sol solution and the addition of PVA and THFA to produce a sol with a viscosity of 40-60 cP. The viscosity range of 40-60cP is the viscosity of the sol solution that was easy to produce a good gel in the gelation apparatus. Sol solution was casted in a gelation column equipped with following tools: a 1 mm diameter drip nozzle which was vibrated to adjust the best frequency and amplitude of vibration, a flow meter to measure the flow rate of sol, flowing of NH3 gas to presolidification process. Gelation column was contained NH4OH solution as gelation medium and gel container to collect gel product. Gel obtained from the gelation process than processed with ageing, washing, drying and calcinations to get round gel and not broken at calcinations up to 500°C. The parameters observed in this research are variation of Zr nitrate concentration, Ce nitrate concentration, ratio of Zr and Ce in the sol and ageing and drying process method which was appropriate to get a good gel. From the gelation processes that has been done, it can be seen that with the presolidification process can be obtained a round gel and without presolidification process, produce not round gel. In the process of ageing to get not broken gel, ageing was done on the rotary flask so that during the ageing, gels rotate in gelation media. Gels, then be washed by dilute ammonium nitrate, demireralized water and iso prophyl alcohol. The washed gel was then dried by vacuum drying to form pores on the gel which become the path for the gases resulting from decomposition of the gel to exit the gel. Vacuum drying can prevent cracking because the pores allow the gel

  2. Principles of formation of the content of an educational electronic resource on the basis of general and didactic patterns of learning

    Directory of Open Access Journals (Sweden)

    Ольга Юрьевна Заславская

    2018-12-01

    Full Text Available The article considers the influence of the development of technical means of teaching on the effectiveness of educational and methodical resources. Modern opportunities of information and communication technologies allow creating electronic educational resources that represent educational information that automates the learning process, provide information assistance, if necessary, collect and process statistical information on the degree of development of the content of the school material by schoolchildren, set an individual trajectory of learning, and so on. The main principle of data organization is the division of the training course into separate sections on the thematic elements and components of the learning process. General regularities include laws that encompass the entire didactic system, and in specific (particular cases, those whose actions extend to a separate component (aspect of the system. From the standpoint of the existence of three types of electronic training modules in the aggregate content of the electronic learning resource - information, control and module of practical classes - the principles of the formation of the electronic learning resource, in our opinion, should regulate all these components. Each of the certain principles is considered in the groups: scientific orientation, methodological orientation, systemic nature, accounting of interdisciplinary connections, fundamentalization, systematic and dosage sequence, rational use of study time, accessibility, minimization, operationalization of goals, unified identification diagnosis.

  3. The module of methodical support in system of electronic educational resources as the innovative element of the modern maintenance of formation

    Directory of Open Access Journals (Sweden)

    Ольга Николаевна Крылова

    2009-06-01

    Full Text Available The article introduces some results of research, which were devoted to evaluation of tearches' mobility to introduce innovations in the contents of education. The author considers innovative potential of modules of the methodical support for system of electronic educational resources.

  4. Charting a Course through CORAL: Texas A&M University Libraries' Experience Implementing an Open-Source Electronic Resources Management System

    Science.gov (United States)

    Hartnett, Eric; Beh, Eugenia; Resnick, Taryn; Ugaz, Ana; Tabacaru, Simona

    2013-01-01

    In 2010, after two previous unsuccessful attempts at electronic resources management system (ERMS) implementation, Texas A&M University (TAMU) Libraries set out once again to find an ERMS that would fit its needs. After surveying the field, TAMU Libraries selected the University of Notre Dame Hesburgh Libraries-developed, open-source ERMS,…

  5. Performance test of a vertically-directed electric-field cavity resonator made for the rapid gelation apparatus with microwave heating

    International Nuclear Information System (INIS)

    Yamagishi, Shigeru; Ogawa, Toru; Hasegawa, Atsushi.

    1996-06-01

    A cavity resonator with vertically-directed electric field was produced and attached to 'the rapid gelation apparatus with microwave heating' previously reported. Using the rapid gelation apparatus, drops of a simulated solution and of U-containing solutions for internal gelation were heated. The results indicated that the heating required for gelation of the U-containing solutions was possible. However, the electric field strength in the cavity resonator at that time was comparable to that causing the discharge due to the gaseous ammonia released from the heated drops. As a result, gel microspheres were not obtained in a stable state. The discussion suggests that the stable gelation would be realized by improving the cavity resonator shape and/or by modifying the power supply accompanied with using a power stabilizer. (author)

  6. Gelation mechanism of poly(N-isopropylacrylamide)-clay nanocomposite hydrogels synthesized by photopolymerization.

    Science.gov (United States)

    Ferse, Bernhard; Richter, Sven; Eckert, Franziska; Kulkarni, Amit; Papadakis, Christine M; Arndt, Karl-Friedrich

    2008-11-04

    The gelation process of poly-(N-isopropylacrylamide)-clay nanocomposite hydrogels (PNIPAAm-clay NC gels) was investigated by dynamic and static light scattering (DLS and SLS), as well as by fluorescence correlation spectroscopy (FCS). The photopolymerization method chosen for the radical polymerizing system ensured that, when the irradiation is removed, the reaction stopped immediately. Experiments showed that shortly before the gelation threshold is reached, no changes in the DLS autocorrelation functions appear, while the monomer conversion can be observed by 1H NMR spectroscopy. These results correspond to the formation of microparticles, in which the PNIPAAm chains are closely attached to the clay platelets. During the further polymerization process, clay clusters are developed before the sol-gel threshold is reached. FCS measurements were performed to obtain information on the motion of the clay platelets inside the NC gel. The DLS method gives only an average of the motions in the gel. In a time window between 10 micros and 1 s, the clay sheets labeled with Rhodamine B show no characteristic motions.

  7. Influence of gamma-irradiation on thermally-induced mesoscopic gelation of degalactosylated xyloglucans

    International Nuclear Information System (INIS)

    Todaro, S.; Sabatino, M.A.; Walo, M.; Mangione, M.R.; Bulone, D.; Dispenza, C.

    2014-01-01

    Thermoresponsive degalactosylated xyloglucans have been already proposed as in situ gelling scaffolds for tissue engineering, due to their reversible macroscopic thermal gelation at body temperature and biodegradability. The highly branched, hydroxyl group-rich molecular structure renders xyloglucans interesting raw materials also in the form of micro/nanoparticles for application as nanoscalar drug delivery devices in cosmetic and pharmaceutical formulations. Owing to their natural source, xyloglucans show high average molecular weight, broad molecular weight distribution and poor water solubility, as large and compact aggregates usually form via inter-molecular hydrogen bonding. 60 Co γ-irradiation has been here applied to reduce the molecular weight. The aqueous solutions of irradiated xyloglucan were characterized by dynamic light scattering measurements and gel filtration chromatography. The aggregation kinetics at 37 °C were studied by dynamic light scattering measurements to confirm the temperature-responsive behavior of this polymer even when dispersed in water at low concentration after γ-irradiation. Irradiation dose–molecular properties relationship has been sought. - Highlights: • Influence of γ-irradiation on a partially degalactosylated xyloglucan is investigated. • Molecular weight reduction is observed in the investigated dose range. • Modification of the temperature-induced mesoscopic gelation kinetics is evidenced

  8. In Situ Gelation-Induced Death of Cancer Cells Based on Proteinosomes.

    Science.gov (United States)

    Zhou, Yuting; Song, Jianmin; Wang, Lei; Xue, Xuting; Liu, Xiaoman; Xie, Hui; Huang, Xin

    2017-08-14

    Hydrogels are an excellent type of material that can be utilized as a platform for cell culture. However, when a bulky hydrogel forms on the inside of cancer cells, the result would be different. In this study, we demonstrate a method for in situ gelation inside cancer cells that can efficiently induce cell death. Glutathione-responsive proteinosomes with good biocompatibility were prepared as carriers for sodium alginate to be endocytosed by cancer cells, where the chelation between sodium alginate and free calcium ions in the culture medium occurs during the diffusion process. The uptake of the hydrogel-loaded proteinosomes into the cancer cells, and then the triggered release of hydrogel with concomitant aggregation, was well-confirmed by monitoring the change of the Young's modulus of the cells based on AFM force measurements. Accordingly, when a large amount of hydrogel formed in cells, the cell viability would be inhibited by ∼90% by MTT assay at a concentration of 5.0 μM of hydrogel-loaded proteinosomes after 48 h incubation, which clearly proves the feasibility of the demonstrated method for killing cancer cells. Although more details regarding the mechanism of cell death should be conducted in the near future, such a demonstrated method of in situ gelation inside cells provides another choice for killing cancer cells.

  9. Intermediate Compound Preparation Using Modified External Gelation Method and Thermal Treatment Equipment Development for UCO Kernel

    Energy Technology Data Exchange (ETDEWEB)

    Jeong, Kyung Chai; Eom, Sung Ho; Kim, Yeon Ku; Yeo, Seoung Hwan; Kim, Young Min; Cho, Moon Sung [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2016-10-15

    VHTR (Very High Temperature Gas Reactor) fuel technology is being actively developed in the US, China, Japan, and Korea for a Next Generation Nuclear Plant (NGNP). The concept of fuel of a VHTR is based on a sphere kernel of UO{sub 2} or UCO, with multiple coating layers to create a gas-tight particle. The fuel particle of a VHTR in the US is based on microspheres containing a UCO, mixture compound of UO{sub 2} and UC{sub 2} , coated particles with multi carbon layers and a SiC layer. This was first prepared through an internal gelation method at ORNL in the late 1970s. This study presents; (1) C-ADU gel particles were prepared using a modified sol-gel process. The particles fabricated with a KAERI-established gelation and AWD processes showed good sphericity and no cracks were found on the surfaces. (2) High temperature rotating furnace was designed and fabricated in our laboratory, and the maximum operation temperature was about 2000℃. The furnace was equipped with Mo crucible and graphite heating system, and now it is being operated. (3) Well-prepared C-ADU gel particles were converted into UCO compounds using high temperature rotating furnace, and the physical properties of the UCO kernels will be analyzed.

  10. Proton triggered circularly polarized luminescence in orthogonal- and co-assemblies of chiral gelators with achiral perylene bisimide.

    Science.gov (United States)

    Han, Dongxue; Han, Jianlei; Huo, Shengwei; Qu, Zuoming; Jiao, Tifeng; Liu, Minghua; Duan, Pengfei

    2018-05-29

    The orthogonal- or co-assembly of achiral perylene bisimide (PBI) with chiral gelators can be regulated by solvents. While the coassembly leads to the formation of chiroptical nanofibers through chirality transfer, the orthogonal assemblies could not. Moreover, protonation on the coassembled nanofibers could light up the circularly polarized luminescence (CPL).

  11. Gels with exceptional thermal stability formed by bis(amino acid) oxalamide gelators and solvents of low polarity.

    Science.gov (United States)

    Makarević, Janja; Jokić, Milan; Frkanec, Leo; Katalenić, Darinka; Zinić, Mladen

    2002-10-07

    Some bis (amino acid) oxalamide gelators form common thermo-reversible gels with various organic solvents but also gels of exceptional thermal stability with some solvents of medium and low polarity; the latter gels can be heated up to 50 degrees C higher temperatures than the bp of the solvent without apparent gel-to-sol transition.

  12. Acid-Induced Cold Gelation of Globular Proteins: Effects of Protein Aggregate Characteristics and Disulfide Bonding on Rheological Properties

    NARCIS (Netherlands)

    Alting, A.C.; Weijers, M.; Hoog, E.H.A. de; Pijpekamp, A.M. van de; Cohen Stuart, M.A.; Hamer, R.J.; Kruif, C.G. de; Visschers, R.W.

    2004-01-01

    The process of cold gelation of ovalbumin and the properties of the resulting cold-set gels were compared to those of whey protein isolate. Under the chosen heating conditions, most protein was organized in aggregates. For both protein preparations, the aggregates consisted of covalently linked

  13. Effect of gelation of inner dispersed phase on stability of (w1/o/w2) multiple emulsions

    NARCIS (Netherlands)

    Oppermann, A.K.L.; Renssen, M.; Schuch, A.; Stieger, M.A.; Scholten, E.

    2015-01-01

    The use of water-in-oil-in-water (w1/o/w2) multiple emulsions offers a method for the reduction of oil in foods. In this study we investigated the influence of osmotic pressure tailoring and gelation of the inner dispersed w1 water droplets on the stability and yield of multiple emulsions. Yield is

  14. In Situ Observations of Thermoreversible Gelation and Phase Separation of Agarose and Methylcellulose Solutions under High Pressure.

    Science.gov (United States)

    Kometani, Noritsugu; Tanabe, Masahiro; Su, Lei; Yang, Kun; Nishinari, Katsuyoshi

    2015-06-04

    Thermoreversible sol-gel transitions of agarose and methylcellulose (MC) aqueous solutions on isobaric cooling or heating under high pressure up to 400 MPa have been investigated by in situ observations of optical transmittance and falling-ball experiments. For agarose, which undergoes the gelation on cooling, the application of pressure caused a gradual rise in the cloud-point temperature over the whole pressure range examined, which is almost consistent with the pressure dependence of gelling temperature estimated by falling-ball experiments, suggesting that agarose gel is stabilized by compression and that the gelation occurs nearly in parallel with phase separation under ambient and high-pressure conditions. For MC, which undergoes the gelation on heating, the cloud-point temperature showed a slight rise with an initial elevation of pressure up to ∼150 MPa, whereas it showed a marked depression above 200 MPa. In contrast, the gelling temperature of MC, which is nearly identical to the cloud-point temperature at ambient pressure, showed a monotonous rise with increasing pressure up to 350 MPa, which means that MC undergoes phase separation prior to gelation on heating under high pressure above 200 MPa. Similar results were obtained for the melting process of MC gel on cooling. The unique behavior of the sol-gel transition of MC under high pressure has been interpreted in terms of the destruction of hydrophobic hydration by compression.

  15. Electronics

    Science.gov (United States)

    2001-01-01

    International Acer Incorporated, Hsin Chu, Taiwan Aerospace Industrial Development Corporation, Taichung, Taiwan American Institute of Taiwan, Taipei, Taiwan...Singapore and Malaysia .5 - 4 - The largest market for semiconductor products is the high technology consumer electronics industry that consumes up...Singapore, and Malaysia . A new semiconductor facility costs around $3 billion to build and takes about two years to become operational

  16. The crucial effect of early-stage gelation on the mechanical properties of cement hydrates

    Science.gov (United States)

    Ioannidou, Katerina; Kanduč, Matej; Li, Lunna; Frenkel, Daan; Dobnikar, Jure; Del Gado, Emanuela

    2016-07-01

    Gelation and densification of calcium-silicate-hydrate take place during cement hydration. Both processes are crucial for the development of cement strength, and for the long-term evolution of concrete structures. However, the physicochemical environment evolves during cement formation, making it difficult to disentangle what factors are crucial for the mechanical properties. Here we use Monte Carlo and Molecular Dynamics simulations to study a coarse-grained model of cement formation, and investigate the equilibrium and arrested states. We can correlate the various structures with the time evolution of the interactions between the nano-hydrates during the preparation of cement. The novel emerging picture is that the changes of the physicochemical environment, which dictate the evolution of the effective interactions, specifically favour the early gel formation and its continuous densification. Our observations help us understand how cement attains its unique strength and may help in the rational design of the properties of cement and related materials.

  17. Transdermal gelation of methacrylated macromers with near-infrared light and gold nanorods

    International Nuclear Information System (INIS)

    Gramlich, William M; Holloway, Julianne L; Rai, Reena; Burdick, Jason A

    2014-01-01

    Injectable hydrogels provide locally controlled tissue bulking and a means to deliver drugs and cells to the body. The formation of hydrogels in vivo may involve the delivery of two solutions that spontaneously crosslink when mixed, with pH or temperature changes, or with light (e.g., visible or ultraviolet). With these approaches, control over the kinetics of gelation, introduction of the initiation trigger (e.g., limited penetration of ultraviolet light through tissues), or alteration of the material physical properties (e.g., mechanics) may be difficult to achieve. To overcome these limitations, we used the interaction of near-infrared (NIR) light with gold nanorods (AuNRs) to generate heat through the photothermal effect. NIR light penetrates tissues to a greater extent than other wavelengths and provides a means to indirectly initiate radical polymerization. Specifically, this heating coupled with a thermal initiator (VA-044) produced radicals that polymerized methacrylated hyaluronic acid (MeHA) and generated hydrogels. A range of VA-044 concentrations changed the gelation time, yielding a system stable at 37 ° C for 22 min that gels quickly (∼3 min) when heated to 55 ° C. With a constant irradiation time (10 min) and laser power (0.3 W), different VA-044 and AuNR concentrations tuned the compressive modulus of the hydrogel. By changing the NIR irradiation time we attained a wide range of moduli at a set solution composition. In vivo mouse studies confirmed that NIR laser irradiation through tissue could gel an injected precursor solution transdermally. (paper)

  18. Transdermal gelation of methacrylated macromers with near-infrared light and gold nanorods

    Science.gov (United States)

    Gramlich, William M.; Holloway, Julianne L.; Rai, Reena; Burdick, Jason A.

    2014-01-01

    Injectable hydrogels provide locally controlled tissue bulking and a means to deliver drugs and cells to the body. The formation of hydrogels in vivo may involve the delivery of two solutions that spontaneously crosslink when mixed, with pH or temperature changes, or with light (e.g., visible or ultraviolet). With these approaches, control over the kinetics of gelation, introduction of the initiation trigger (e.g., limited penetration of ultraviolet light through tissues), or alteration of the material physical properties (e.g., mechanics) may be difficult to achieve. To overcome these limitations, we used the interaction of near-infrared (NIR) light with gold nanorods (AuNRs) to generate heat through the photothermal effect. NIR light penetrates tissues to a greater extent than other wavelengths and provides a means to indirectly initiate radical polymerization. Specifically, this heating coupled with a thermal initiator (VA-044) produced radicals that polymerized methacrylated hyaluronic acid (MeHA) and generated hydrogels. A range of VA-044 concentrations changed the gelation time, yielding a system stable at 37 ° C for 22 min that gels quickly (˜3 min) when heated to 55 ° C. With a constant irradiation time (10 min) and laser power (0.3 W), different VA-044 and AuNR concentrations tuned the compressive modulus of the hydrogel. By changing the NIR irradiation time we attained a wide range of moduli at a set solution composition. In vivo mouse studies confirmed that NIR laser irradiation through tissue could gel an injected precursor solution transdermally.

  19. Evaluation of three electronic report processing systems for preparing hydrologic reports of the U.S Geological Survey, Water Resources Division

    Science.gov (United States)

    Stiltner, G.J.

    1990-01-01

    In 1987, the Water Resources Division of the U.S. Geological Survey undertook three pilot projects to evaluate electronic report processing systems as a means to improve the quality and timeliness of reports pertaining to water resources investigations. The three projects selected for study included the use of the following configuration of software and hardware: Ventura Publisher software on an IBM model AT personal computer, PageMaker software on a Macintosh computer, and FrameMaker software on a Sun Microsystems workstation. The following assessment criteria were to be addressed in the pilot studies: The combined use of text, tables, and graphics; analysis of time; ease of learning; compatibility with the existing minicomputer system; and technical limitations. It was considered essential that the camera-ready copy produced be in a format suitable for publication. Visual improvement alone was not a consideration. This report consolidates and summarizes the findings of the electronic report processing pilot projects. Text and table files originating on the existing minicomputer system were successfully transformed to the electronic report processing systems in American Standard Code for Information Interchange (ASCII) format. Graphics prepared using a proprietary graphics software package were transferred to all the electronic report processing software through the use of Computer Graphic Metafiles. Graphics from other sources were entered into the systems by scanning paper images. Comparative analysis of time needed to process text and tables by the electronic report processing systems and by conventional methods indicated that, although more time is invested in creating the original page composition for an electronically processed report , substantial time is saved in producing subsequent reports because the format can be stored and re-used by electronic means as a template. Because of the more compact page layouts, costs of printing the reports were 15% to 25

  20. Electronic resources of the rare books and valuable editions department of the Central Scientific Library of the V.N. Karazin Kharkiv National University: open access for research

    Directory of Open Access Journals (Sweden)

    І. К. Журавльова

    2014-12-01

    Full Text Available The article describes tasks that electronic collections of rare books fulfill: broad access for readers to rare and valuable editions providing, preservation of ensuring of the original. On the example of the electronic collection of the Central Scientific Library of the V.N. Karazin Kharkiv National University – «eScriptorium: electronic archive of rare books and manuscripts for research and education» the possibility of the full-text resources of the valuable editions using is shown. The principles of creation, structure, chronological frameworks, directions of adding the documents to the archive are represented. The perspectives of the project development are outlined as well as examples of the digital libraries of the European countries and Ukraine are provided, the actual task of preserving the originals of the rare books of the country is raised, the innovative approaches to serving users with electronic resources are considered. The evidences of cooperation of the Central Scientific Library of the V.N. Karazin Kharkiv National University with the largest world digital libraries: World Digital Library and Europeana are provided.

  1. The use of quality benchmarking in assessing web resources for the dermatology virtual branch library of the National electronic Library for Health (NeLH).

    Science.gov (United States)

    Kamel Boulos, M N; Roudsari, A V; Gordon, C; Muir Gray, J A

    2001-01-01

    In 1998, the U.K. National Health Service Information for Health Strategy proposed the implementation of a National electronic Library for Health to provide clinicians, healthcare managers and planners, patients and the public with easy, round the clock access to high quality, up-to-date electronic information on health and healthcare. The Virtual Branch Libraries are among the most important components of the National electronic Library for Health. They aim at creating online knowledge based communities, each concerned with some specific clinical and other health-related topics. This study is about the envisaged Dermatology Virtual Branch Libraries of the National electronic Library for Health. It aims at selecting suitable dermatology Web resources for inclusion in the forthcoming Virtual Branch Libraries after establishing preliminary quality benchmarking rules for this task. Psoriasis, being a common dermatological condition, has been chosen as a starting point. Because quality is a principal concern of the National electronic Library for Health, the study includes a review of the major quality benchmarking systems available today for assessing health-related Web sites. The methodology of developing a quality benchmarking system has been also reviewed. Aided by metasearch Web tools, candidate resources were hand-selected in light of the reviewed benchmarking systems and specific criteria set by the authors. Over 90 professional and patient-oriented Web resources on psoriasis and dermatology in general are suggested for inclusion in the forthcoming Dermatology Virtual Branch Libraries. The idea of an all-in knowledge-hallmarking instrument for the National electronic Library for Health is also proposed based on the reviewed quality benchmarking systems. Skilled, methodical, organized human reviewing, selection and filtering based on well-defined quality appraisal criteria seems likely to be the key ingredient in the envisaged National electronic Library for

  2. Barriers to electronic access and delivery of educational information in resource constrained public schools: a case of Greater Tubatse Municipality

    CSIR Research Space (South Africa)

    Pholotho, T

    2016-05-01

    Full Text Available Information and Communication Technologies (ICTs) are capable of expanding access to quality education, educational resources and provide teachers with new skills. Nevertheless, a majority of rural public schools have limited ICTs, mainly due...

  3. Electronic Grey Literature in Accelerator Science and Its Allied Subjects : Selected Web Resources for Scientists and Engineers

    CERN Document Server

    Rajendiran, P

    2006-01-01

    Grey literature Web resources in the field of accelerator science and its allied subjects are collected for the scientists and engineers of RRCAT (Raja Ramanna Centre for Advanced Technology). For definition purposes the different types of grey literature are described. The Web resources collected and compiled in this article (with an overview and link for each) specifically focus on technical reports, preprints or e-prints, which meet the main information needs of RRCAT users.

  4. Bis(PheOH) maleic acid amide-fumaric acid amide photoizomerization induces microsphere-to-gel fiber morphological transition: the photoinduced gelation system.

    Science.gov (United States)

    Frkanec, Leo; Jokić, Milan; Makarević, Janja; Wolsperger, Kristina; Zinić, Mladen

    2002-08-21

    The photoinduced gelation system based on 1 (non-gelling) to 2 (gelling) molecular photoisomerization in water results by microspheres (1) to gel fibers (2) transformation at the supramolecular level.

  5. Towards a fully synthetic substitute of alginate: optimization of a thermal gelation/chemical cross-linking scheme ("tandem" gelation) for the production of beads and liquid-core capsules.

    Science.gov (United States)

    Cellesi, F; Weber, W; Fussenegger, M; Hubbell, J A; Tirelli, N

    2004-12-20

    Fully synthetic polymers were used for the preparation of hydrogel beads and capsules, in a processing scheme that, originally designed for calcium alginate, was adapted to a "tandem" process, that is the combination a physical gelation with a chemical cross-linking. The polymers feature a Tetronic backbone (tetra armed Pluronics), which exhibits a reverse thermal gelation in water solutions within a physiological range of temperatures and pHs. The polymers bear terminal reactive groups that allow for a mild, but effective chemical cross-linking. Given an appropriate temperature jump, the thermal gelation provides a hardening kinetics similar to that of alginate. With slower kinetics, the chemical cross-linking then develops an irreversible and elastic gel structure, and determines its transport properties. In the present article this process has been optimized for the production of monodisperse, high elastic, hydrogel microbeads, and liquid-core microcapsules. We also show the feasibility of the use of liquid-core microcapsules in cell encapsulation. In preliminary experiments, CHO cells have been successfully encapsulated preserving their viability during the process and after incubation. The advantages of this process are mainly in the use of synthetic polymers, which provide great flexibility in the molecular design. This, in principle, allows for a precise tailoring of mechanical and transport properties and of bioactivity of the hydrogels, and also for a precise control in material purification.

  6. Study for process and equipment design of wet gelation stages in vibropacking process

    International Nuclear Information System (INIS)

    Tanimoto, Ryoji; Kikuchi, Toshiaki; Tanaka, Hirokazu; Amino, Masaki; Yanai, Minoru

    2004-02-01

    Process and layout design of external wet gelation stages in vibropacking process was examined for the feasibility study of commercialized FBR cycle system. In this study, following process stages for the oxide core fuel production line were covered, that is, solidification, washing, drying, calcination, reduction, sintering stages including interim storage of sintering particles and reagent recovery stage. The main results obtained by this study are as follows: (1) Based on the process examination results conducted previously, process-flow, mass-balance and number of production line/equipment were clarified. The process is covered from the receive tank of feed solution to the interim storage equipment. Reagent recovery process-flow, mass-balance were also clarified. And preliminary design of the main equipment was reexamined. (2) Normal operation procedure and the procedure after process failure were summarized along with a remote automated operation procedure. Operation sequence of each production line was mapped out by using a time-chart. (3) Design outline of reagent recovery equipments, installed to recover waste liquid from the wet gelation stages in the view of environmental impact were examined. Effective techniques such as collection of solvent, residue waste treatment method were examined its applicability and selected. Schematic block diagram was presented. (4) Analytical items and analyzing apparatus were extracted taking into account of quality control and process management. Analytical sample taking position and frequency of sampling were also examined. (5) A schematic layout drawing of main manufacturing process and reagent recovery process was presented taking into account of material handling. (6) A feature of the operating rate at each process stage was examined by analyzing failure rate reliability of each component. applying the reliability-centred method. (RCM), the operating rate was evaluated and annual maintenance period was estimated using

  7. Efficient Synthesis of MCu (M = Pd, Pt, and Au) Aerogels with Accelerated Gelation Kinetics and their High Electrocatalytic Activity.

    Science.gov (United States)

    Zhu, Chengzhou; Shi, Qiurong; Fu, Shaofang; Song, Junhua; Xia, Haibing; Du, Dan; Lin, Yuehe

    2016-10-01

    To accelerate hydrogel formation and further simplify the synthetic procedure, a series of MCu (M = Pd, Pt, and Au) bimetallic aerogels is synthesized from the in situ reduction of metal precursors through enhancement of the gelation kinetics at elevated temperature. Moreover, the resultant PdCu aerogel with ultrathin nanowire networks exhibits excellent electrocatalytic performance toward ethanol oxidation, holding promise in fuel-cell applications. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Production of Monodisperse Cerium Oxide Microspheres with Diameters near 100 µm by Internal Gelation Sol-Gel Methods

    Energy Technology Data Exchange (ETDEWEB)

    Katalenich, Jeffrey A.; Kitchen, Brian B.; Pierson, Bruce

    2018-05-01

    Internal gelation sol-gel methods have used a variety of sphere forming methods in the past to produce metal oxide microspheres, but typically with poor control over the size uniformity at diameters near 100 µm. This work describes efforts to make and measure internal gelation, sol-gel microspheres with very uniform diameters in the 100 – 200 µm size range using a two-fluid nozzle. A custom apparatus was used to form aqueous droplets of sol-gel feed solutions in silicone oil and heat them to cause gelation of the spheres. Gelled spheres were washed, dried, and sintered prior to mounting on glass slides for optical imaging and analysis. Microsphere diameters and shape factors were determined as a function of silicone oil flow rate in a two-fluid nozzle and the size of a needle dispensing the aqueous sol-gel solution. Nine batches of microspheres were analyzed and had diameters ranging from 65.5 ± 2.4 µm for the smallest needle and fastest silicone oil flow rate to 211 ± 4.7 µm for the largest needle and slowest silicone oil flow rate. Standard deviations for measured diameters were less than 8% for all samples and most were less than 4%. Microspheres had excellent circularity with measured shape factors of 0.9 – 1. However, processing of optical images was complicated by shadow effects in the photoresist layer on glass slides and by overlapping microspheres. Based on calculated flow parameters, microspheres were produced in a simple dripping mode in the two-fluid nozzle. Using flow rates consistent with a simple dripping mode in a two-fluid nozzle configuration allows for very uniform oxide microspheres to be produced using the internal-gelation sol-gel method.

  9. Determination of heat-set gelation capacity of a quinoa protein isolate (Chenopodium quinoa) by dynamic oscillatory rheological analysis.

    Science.gov (United States)

    Kaspchak, Elaine; Oliveira, Marco Aurelio Schüler de; Simas, Fernanda Fogagnoli; Franco, Célia Regina Cavicchiolo; Silveira, Joana Léa Meira; Mafra, Marcos Rogério; Igarashi-Mafra, Luciana

    2017-10-01

    This work aimed to study the influence of pH (3.5 and 7.0) and CaCl 2 and MgCl 2 addition on heat-set gelation of a quinoa protein isolate at 10% and 15% (w/w). The protein isolate obtained was composed mainly of 11S globulin as was observed by electrophoresis and mass spectrometry analysis. Heat-set gelation occurred at both pH values studied. Nevertheless, the gels formed at pH 3.5 were more viscoelastic and denser than those formed at pH 7.0, that was coarser and presented syneresis. The CaCl 2 and MgCl 2 addition increased the gel strength during rheological analysis at pH 3.5, possibly due to the formation of fiber-like connections in the gel network. At pH 7.0, the divalent salts resulted in weaker gels formed by agglomerates, suggesting a neutralization of the protein surface charges. The differences in quinoa protein gelation were attributed to solubility, and the flexibility of proteins secondary structure at the pH studied. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Clinician‐selected Electronic Information Resources do not Guarantee Accuracy in Answering Primary Care Physicians’ Information Needs. A review of: McKibbon, K. Ann, and Douglas B. Fridsma. “Effectiveness of Clinician‐selected Electronic Information Resources for Answering Primary Care Physicians’ Information Needs.” Journal of the American Medical Informatics Association 13.6 (2006: 653‐9.

    Directory of Open Access Journals (Sweden)

    Martha Ingrid Preddie

    2008-03-01

    Full Text Available Objective – To determine if electronic information resources selected by primary care physicians improve their ability to answer simulated clinical questions.Design – An observational study utilizing hour‐long interviews and think‐aloud protocols.Setting – The offices and clinics of primary care physicians in Canada and the United States.Subjects – Twenty‐five primary care physicians of whom 4 were women, 17 were from Canada, 22 were family physicians,and 24 were board certified.Methods – Participants provided responses to 23 multiple‐choice questions. Each physician then chose two questions and looked for the answers utilizing information resources of their own choice. The search processes, chosen resources and search times were noted. These were analyzed along with data on the accuracy of the answers and certainties related to the answer to each clinical question prior to the search.Main results – Twenty‐three physicians sought answers to 46 simulated clinical questions. Utilizing only electronic information resources, physicians spent a mean of 13.0 (SD 5.5 minutes searching for answers to the questions, an average of 7.3(SD 4.0 minutes for the first question and 5.8 (SD 2.2 minutes to answer the second question. On average, 1.8 resources were utilized per question. Resources that summarized information, such as the Cochrane Database of Systematic Reviews, UpToDate and Clinical Evidence, were favored 39.2% of the time, MEDLINE (Ovid and PubMed 35.7%, and Internet resources including Google 22.6%. Almost 50% of the search and retrieval strategies were keyword‐based, while MeSH, subheadings and limiting were used less frequently. On average, before searching physicians answered 10 of 23 (43.5% questions accurately. For questions that were searched using clinician‐selected electronic resources, 18 (39.1% of the 46 answers were accurate before searching, while 19 (42.1% were accurate after searching. The difference of

  11. Synthesis and Characterization of New Thiolated Chitosan Nanoparticles Obtained by Ionic Gelation Method

    Directory of Open Access Journals (Sweden)

    Reynaldo Esquivel

    2015-01-01

    Full Text Available We derivatized low molecular weight chitosan (LMWC with 3-mercaptopropanoic acid (3-MPA by a coupling reaction. The chemical modification of LMWC was characterized by Fourier transform infrared spectroscopy (FT-IR and nuclear magnetic resonance, 1HNMR. We researched the influence of 3-MPA on the nanoparticles formation by ionic gelation method using sodium tripolyphosphate (TPP as cross-linker reagent. In order to optimize the nanoparticles formation, we studied the effect of the pH solution and molar ratio on nanoparticles stability. Analyses of particle size, morphology, and surface charge were determined by dynamic light scattering, Atomic Force Microscopy, and zeta potential, respectively. It was found that formation of semispherical and stable nanoparticles was improved due to the chemical modification of chitosan. Optimized semispherical nanoparticles of thiolated chitosan were synthesized with the parameters (pH 4.7, molar ratios 1 : 106. Additionally, we reported the thermodynamic profile of the nanoparticles formation determined by isothermal titration calorimetry (ITC. The aggregation process achieved to form nanoparticles of thiolated and nonmodified chitosan consisted of two stages, considering one binding site model. Gibbs free energy (ΔG and binding constant (Ka describe the aggregation process of thiolated chitosan/TPP, which is an initial reaction and followed by an endothermic stage. These results are promising for the possible application of these nanoparticles as nanocarriers and delivery systems.

  12. Coupling the Alkaline-Surfactant-Polymer Technology and The Gelation Technology to Maximize Oil Production

    Energy Technology Data Exchange (ETDEWEB)

    Malcolm Pitts; Jie Qi; Dan Wilson; Phil Dowling; David Stewart; Bill Jones

    2005-12-01

    Performance and produced polymer evaluation of four alkaline-surfactant-polymer projects concluded that only one of the projects could have benefited from combining the alkaline-surfactant-polymer and gelation technologies. Cambridge, the 1993 Daqing, Mellott Ranch, and the Wardlaw alkaline-surfacant-polymer floods were studied. An initial gel treatment followed by an alkaline-surfactant-polymer flood in the Wardlaw field would have been a benefit due to reduction of fracture flow. Numerical simulation demonstrated that reducing the permeability of a high permeability zone of a reservoir with gel improved both waterflood and alkaline-surfactant-polymer flood oil recovery. A Minnelusa reservoir with both A and B sand production was simulated. A and B sands are separated by a shale layer. A sand and B sand waterflood oil recovery was improved by 196,000 bbls or 3.3% OOIP when a gel was placed in the B sand. Alkaline-surfactant-polymer flood oil recovery improvement over a waterflood was 392,000 bbls or 6.5% OOIP. Placing a gel into the B sand prior to an alkaline-surfactant-polymer flood resulted in 989,000 bbl or 16.4% OOIP more oil than only water injection. A sand and B sand alkaline-surfactant-polymer flood oil recovery was improved by 596,000 bbls or 9.9% OOIP when a gel was placed in the B sand.

  13. Encapsulating anthocyanins from Hibiscus sabdariffa L. calyces by ionic gelation: Pigment stability during storage of microparticles.

    Science.gov (United States)

    de Moura, Sílvia C S R; Berling, Carolina L; Germer, Sílvia P M; Alvim, Izabela D; Hubinger, Míriam D

    2018-02-15

    Hibiscus extract (HE) has a strong antioxidant activity and high anthocyanin content; it can be used as a natural pigment, also adding potential health benefits. The objective of this work was the microencapsulation of HE anthocyanin by ionic gelation (IG) using two techniques: dripping-extrusion and atomization, both by means of a double emulsion (HE/rapseed oil/pectin) and a cross-linked solution (CaCl 2 ). Particles (77-83% moisture content) were conditioned in acidified solution at 5, 15 and 25°C, absence of light, and evaluated for anthocyanins and color for 50-days. The median diameter (D 50 ) of the particles ranged from 78 to 1100μm and encapsulation efficiency ranged from 67.9 to 93.9%. The encapsulation caused higher temperature stability compared with the free extract. The half-life (t 1/2 ) values of the particles ranged from 7 (25°C) to 180days (5°C) for anthocyanins and from 25 (25°C) to 462days (5°C) for Chroma value. The IG increased the stability of HE anthocyanin. Both the dripping-extrusion and the atomization have shown to be feasible techniques. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Nanoparticle and gelation stabilized functional composites of an ionic salt in a hydrophobic polymer matrix.

    Directory of Open Access Journals (Sweden)

    Selin Kanyas

    Full Text Available Polymer composites consisted of small hydrophilic pockets homogeneously dispersed in a hydrophobic polymer matrix are important in many applications where controlled release of the functional agent from the hydrophilic phase is needed. As an example, a release of biomolecules or drugs from therapeutic formulations or release of salt in anti-icing application can be mentioned. Here, we report a method for preparation of such a composite material consisted of small KCOOH salt pockets distributed in the styrene-butadiene-styrene (SBS polymer matrix and demonstrate its effectiveness in anti-icing coatings. The mixtures of the aqueous KCOOH and SBS-cyclohexane solutions were firstly stabilized by adding silica nanoparticles to the emulsions and, even more, by gelation of the aqueous phase by agarose. The emulsions were observed in optical microscope to check its stability in time and characterized by rheological measurements. The dry composite materials were obtained via casting the emulsions onto the glass substrates and evaporations of the organic solvent. Composite polymer films were characterized by water contact angle (WCA measurements. The release of KCOOH salt into water and the freezing delay experiments of water droplets on dry composite films demonstrated their anti-icing properties. It has been concluded that hydrophobic and thermoplastic SBS polymer allows incorporation of the hydrophilic pockets/phases through our technique that opens the possibility for controlled delivering of anti-icing agents from the composite.

  15. Combined effects of presalted prerigor and postrigor batter mixtures on chicken breast gelation.

    Science.gov (United States)

    Choi, Yun-Sang; Kim, Hyun-Wook; Hwang, Ko-Eun; Song, Dong-Hun; Jeong, Tae-Jun; Jeon, Ki-Hong; Kim, Young-Boong; Kim, Cheon-Jei

    2015-04-01

    We examined the combined effects of prerigor and postrigor batter mixtures on protein gelation. The postrigor batter was prepared with 2% salt, whereas the prerigor meat at 5 min postmortem was used to prepare postrigor batters at different salt levels. For 5 treatments, prerigor batters were mixed with postrigor batter that had 2% salt (control) as follows: T1: ground presalted (1%) hot-boned breast with 1% salt for 50% total batch; T2: ground presalted (2%) hot-boned breast for 50% total batch; T3: ground presalted (3%) hot-boned breast for 30% total batch that was mixed with cold-boned batter for 50% total batch; T4: ground presalted (4%) hot-boned breast for 25% total batch that was mixed with cold-boned batter for 50% total batch; and T5: ground presalted (5%) hot-boned breast for 20% total batch that was mixed with cold-boned batter for 50% total batch. Treatments with both presalted prerigor and postrigor muscle showed less cooking loss and lower emulsion stability than the control, except T5. The protein solubility and apparent viscosity of the control was the lowest. Thus, presalted hot-boned muscle combined with cold-boned muscle positively affected physicochemical properties. © 2015 Poultry Science Association Inc.

  16. Gelation in a model 1-component system with adhesive hard-sphere interactions

    Science.gov (United States)

    Kim, Jung Min; Eberle, Aaron; Fang, Jun; Wagner, Norman

    2012-02-01

    Colloidal dispersions can undergo a dynamical arrest of the disperse phase leading to a system with solid-like properties when either the volume fraction or the interparticle potential is varied. Systems that contain low to moderate particulate concentrations form gels whereas higher concentrations lead to glassy states in which caging by nearest neighbors can be a significant contributor to the arrested long-time dynamics. Colloid polymer mixtures have been the prevalent model system for studying the effect of attraction, where attractions are entropically driven by depletion effects, in which gelation has been shown to be a result of phase separation [1]. Using the model 1-component octadecyl coated silica nanoparticle system, Eberle et al. [2] found the gel-line to intersect the spinodal to the left of the critical point, and at higher concentrations extended toward the mode coupling theory attractive driven glass line. . We continue this study by varying the particle diameter and find quantitative differences which we explain by gravity. 1. Lu, P.J., et al., Nature, 2008. 453(7194): p. 499-504.2. Eberle, A.P.R., N.J. Wagner, and R. Castaneda-Priego, Physical Review Letters, 2011. 106(10).

  17. Self-Paced Interactive Multimedia Courseware: A Learning Support Resource for Enhancing Electronic Theses and Dissertations Development

    Science.gov (United States)

    Essel, Harry Barton; Osei-Poku, Patrick; Tachie-Menson, Akosua; Opoku-Asare, Nana Afia

    2016-01-01

    Submission of Electronic Theses and Dissertations (ETDs) by postgraduate students has become a common phenomenon in learning environments globally. The purpose of ETDs is to train postgraduate students as knowledge workers in online publishing and also extend their skills beyond word processing. The challenge however, is that many postgraduate…

  18. Web Accessibility Issues for Higher & Further Education. EDNER (Formative Evaluation of the Distributed National Electronic Resource) Project. Issues Paper.

    Science.gov (United States)

    Manchester Metropolitan Univ. (England).

    This issues paper, sixth in a series of eight, is intended to distill formative evaluation questions on topics that are central to the development of the higher and further education information environment in the United Kingdom. In undertaking formative evaluation studies, the Formative Evaluation of the Distributed National Electronic Resource…

  19. Analyzing the Academic Research Trends by Using University Digital Resources: A Bibliometric Study of Electronic Commerce in China

    Science.gov (United States)

    Fatima, Anam; Abbas, Asad; Ming, Wan; Zaheer, Ahmad Nawaz; Akhtar, Masood-ul-Hassan

    2017-01-01

    Technology plays a vital role in every field of life especially in business and education. Electronic commerce (EC) begins in the year of 1991 right after internet was introduced for commercial use. It is known to be the 12th five years' plan (2011 to 2015) of Chinese Ministry of Industry and Information Technology. The main "objective"…

  20. Green Supply Chain Collaboration for Fashionable Consumer Electronics Products under Third-Party Power Intervention—A Resource Dependence Perspective

    OpenAIRE

    Jiuh-Biing Sheu

    2014-01-01

    Under third-party power intervention (TPPI), which increases uncertainty in task environments, complex channel power interplays and restructuring are indispensable among green supply chain members as they move toward sustainable collaborative relationships for increased viability and competitive advantage. From the resource dependence perspective, this work presents a novel conceptual model to investigate the influence of political and social power on channel power restructuring and induced ...

  1. Share and share alike: encouraging the reuse of academic resources through the Scottish electronic Staff Development Library

    Directory of Open Access Journals (Sweden)

    Lorna M. Campbell

    2001-12-01

    Full Text Available The Scottish electronic Staff Development Library (http://www.sesdl.scotcit.acuk is an ongoing collaborative project involving the Universities of Edinburgh, Paisley and Strathclyde which has been funded by SHEFC as part of their current ScotCIT Programme (http:llwww.scotcit.ac.uk. This project is being developed in response to the increasing demand for flexible, high-quality staff development materials.

  2. Fabrication of uranium-based ceramics using internal gelation for the conversion of trivalent actinides; Herstellung uranbasierter Keramiken mittel interner Gelierung zur Konversion trivalenter Actinoiden

    Energy Technology Data Exchange (ETDEWEB)

    Daniels, Henrik

    2012-07-01

    Alternative to today's direct final waste disposal strategy of long-lived radionuclides, for example the minor actinides neptunium, americium, curium and californium, is their selective separation from the radioactive wastestream with subsequent transmutation by neutron irradiation. Hereby it is possible to obtain nuclides with a lower risk-potential concerning their radiotoxicity. 1 neutron irradiation can be carried out either with neutron sources or in the next generation of nuclear reactors. Before the treatment, the minor actinides need to be converted in a suitable chemical and physical form. Internal gelation offers a route through which amorphous gel-spheres can be obtained directly from a metal-salt solution. Due to the presence of different types of metal ions as well as changing pH-values in a stock solution, a complex hydrolysis behaviour of these elements before and during gelation occurs. Therefore, investigations with uranium and neodymium as a minor actinide surrogate were carried out. As a result of suitable gelation-parameters, uraniumneodymium gel-spheres were successfully synthesised. The spheres also stayed intact during the subsequent thermal treatment. Based upon these findings, uranium-plutonium and uranium-americium gels were successfully created. For theses systems, the determined parameters for the uraniumneodymium gelation could also be applied. Additionally, investigations to reduce the acidity of uranium-based stock solutions for internal gelation were carried out. The necessary amount of urea and hexamethylenetetramine to induce gelation could hereby be decreased. This lead to a general increase of the gel quality and made it possible to carry out uranium-americium gelation in the first place. To investigate the stability of urea and hexamethylenetetramine, solutions of these chemicals were irradiated with different radiation doses. These chemicals showed a high stability against radiolysis in aqueous solutions.

  3. Success factors for implementing and sustaining a mature electronic medical record in a low-resource setting: a case study of iSanté in Haiti.

    Science.gov (United States)

    deRiel, E; Puttkammer, N; Hyppolite, N; Diallo, J; Wagner, S; Honoré, J G; Balan, J G; Celestin, N; Vallès, J S; Duval, N; Thimothé, G; Boncy, J; Coq, N R L; Barnhart, S

    2018-03-01

    Electronic health information systems, including electronic medical records (EMRs), have the potential to improve access to information and quality of care, among other things. Success factors and challenges for novel EMR implementations in low-resource settings have increasingly been studied, although less is known about maturing systems and sustainability. One systematic review identified seven categories of implementation success factors: ethical, financial, functionality, organizational, political, technical and training. This case study applies this framework to iSanté, Haiti's national EMR in use in more than 100 sites and housing records for more than 750 000 patients. The author group, consisting of representatives of different agencies within the Haitian Ministry of Health (MSPP), funding partner the Centers for Disease Control and Prevention (CDC) Haiti, and implementing partner the International Training and Education Center for Health (I-TECH), identify successes and lessons learned according to the seven identified categories, and propose an additional cross-cutting category, sustainability. Factors important for long-term implementation success of complex information systems are balancing investments in hardware and software infrastructure upkeep, user capacity and data quality control; designing and building a system within the context of the greater eHealth ecosystem with a plan for interoperability and data exchange; establishing system governance and strong leadership to support local system ownership and planning for system financing to ensure sustainability. Lessons learned from 10 years of implementation of the iSanté EMR system are relevant to sustainability of a full range of increasingly interrelated information systems (e.g. for laboratory, supply chain, pharmacy and human resources) in the health sector in low-resource settings. © The Author 2017. Published by Oxford University Press in association with The London School of Hygiene

  4. Intragastric Gelation of Heated Soy Protein Isolate-Alginate Mixtures and Its Effect on Sucrose Release.

    Science.gov (United States)

    Huang, Zhaozhi; Gruen, Ingolf; Vardhanabhuti, Bongkosh

    2018-06-15

    The goal of our study was to investigate the effect of alginate on in vitro gastric digestion and sucrose release of soy protein isolate (SPI) in model beverages. Model beverages containing 5% w/w SPI, 0% to 0.20% w/w alginate, and 10% w/w sucrose were prepared by heating the mixtures at 85 °C for 30 min at pH 6.0 or 7.0. Characterizations of beverages included determination of zeta potential, particle size and rheological properties. Digestion patterns and sucrose release profiles were determined during 2 hr in vitro gastric digestion using SDS-PAGE and HPLC analysis, respectively. Increasing alginate concentration led to increased negative surface charge, particle size, as well as viscosity and pseudoplastic behavior; however, no phase separation was observed. SPI beverages formed intragastric gel during in vitro gastric digestion when the formulations contained alginate or at pH 6.0 without alginate. Formation of the intragastric gel led to delayed protein digestion and release of sucrose. Higher resistance to digestion and a slower sucrose release rate were exhibited at increased alginate concentration, and to a lesser extent, at pH 6.0. This suggests that electrostatic interaction between SPI and alginate that occurred when the beverages were under gastric condition could be responsible for the intragastric gelation. These results could potentially lead to the formulation of SPI beverages with functionality to lower postprandial glycemic response. The results could be used to design beverages or semi solid food products with altered digestion properties and lowered or slower glucose release. © 2018 Institute of Food Technologists®.

  5. COUPLING THE ALKALINE-SURFACTANT-POLYMER TECHNOLOGY AND THE GELATION TECHNOLOGY TO MAXIMIZE OIL PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Malcolm Pitts; Jie Qui; Dan Wilson; Phil Dowling

    2004-05-01

    Gelation technologies have been developed to provide more efficient vertical sweep efficiencies for flooding naturally fractured oil reservoirs or more efficient areal sweep efficiency those with high permeability contrast ''thief zones''. The field proven alkaline-surfactant-polymer technology economically recovers 15% to 25% OOIP more oil than waterflooding in the swept pore space of an oil reservoir. However, alkaline-surfactant-polymer technology is not amenable to the naturally fractured reservoirs or those with thief zones because much of the injected solution bypasses the target pore space containing oil. The objective of this work is to investigate whether combining these two technologies could broaden the applicability of alkaline-surfactant-polymer flooding into these reservoirs. Fluid-fluid interaction with different gel chemical compositions and alkaline-surfactant-polymer solution with pH values ranging from 9.2 to 12.9 have been tested. Aluminum-polyacrylamide gels are not stable to alkaline-surfactant-polymer solutions at any pH. Chromium--polyacrylamide gels with polymer to chromium ion ratios of 25 or greater were stable to alkaline-surfactant-polymer solutions if solution pH was 10.6 or less. When the polymer to chromium ion was 15 or less, chromium-polyacrylamide gels were stable to alkaline-surfactant-polymer solutions with pH values up to 12.9. Chromium-xanthan gum gels were stable to alkaline-surfactant-polymer solutions with pH values of 12.9 at the polymer to chromium ion ratios tested. Silicate-polyacrylamide, resorcinol-formaldehyde, and sulfomethylated resorcinol-formaldehyde gels were also stable to alkaline-surfactant-polymer solutions with pH values ranging from 9.2 to 12.9. Iron-polyacrylamide gels were immediately destroyed when contacted with any of the alkaline-surfactant-polymer solutions with pH values of 9.2 to 12.9.

  6. Production of BCG alginate-PLL microcapsules by emulsification/internal gelation.

    Science.gov (United States)

    Esquisabel, A; Hernández, R M; Igartua, M; Gascón, A R; Calvo, B; Pedraz, J L

    1997-01-01

    A biocompatible emulsification method for microencapsulation of live cells and enzymes within a calcium alginate matrix applied to Bacillus Calmette-Guérin (BCG) has been developed. Small-diameter alginate beads (microcapsules) were formed via internal gelation of an alginate solution emulsified within vegetable oil. Five different oils (sesame, sweet almond, perhydrosqualene, camomile and jojoba) were used. The rheological analysis of the oils showed a Newtonian behaviour, with viscosities = 30.0, 37.7, 51.2, 59.3 and 67.1 mPa.s for perhydrosqualene, jojoba, camomile, sesame and sweet almond oil respectively. The particle size of the microcapsules obtained ranged from 30.3 microns for the microcapsules prepared with sweet almond oil to 57.0 microns for those made with perhydrosqualene. The mean particle diameter obtained was found to be dependent on the viscosity of the oil employed, according to the equation: phi (micron) = 76.6-0.628 eta (mPa.s) (r2 = 0.943). The encapsulated BCG was identified by the Difco TB stain set K, followed by observation under optical microscopy. Freeze-drying of the microcapsules was carried out to ensure their stability during storage. Two batches of microcapsules (those prepared with sesame and jojoba oil) and four types of cryoprotectors (glucose, trehalose, mannitol and sorbitol), at three concentration levels (5, 10 and 20% w/v) were studied. The parameters evaluated were particle size, physical appearance, reconstitution of lyophilizates and microscopical evaluation. For both batches of microcapsules the best results were obtained with trehalose 5%, showing particle sizes of 42.1 microns in the case of the microcapsules prepared with sesame oil, and of 45.3 microns for those prepared with jojoba.

  7. COUPLING THE ALKALINE-SURFACTANT-POLYMER TECHNOLOGY AND THE GELATION TECHNOLOGY TO MAXIMIZE OIL PRODUCTION

    Energy Technology Data Exchange (ETDEWEB)

    Malcolm Pitts; Jie Qi; Dan Wilson

    2004-10-01

    Gelation technologies have been developed to provide more efficient vertical sweep efficiencies for flooding naturally fractured oil reservoirs or more efficient areal sweep efficiency for those with high permeability contrast ''thief zones''. The field proven alkaline-surfactant-polymer technology economically recovers 15% to 25% OOIP more oil than waterflooding from swept pore space of an oil reservoir. However, alkaline-surfactant-polymer technology is not amenable to naturally fractured reservoirs or those with thief zones because much of injected solution bypasses target pore space containing oil. This work investigates whether combining these two technologies could broaden applicability of alkaline-surfactant-polymer flooding into these reservoirs. A prior fluid-fluid report discussed interaction of different gel chemical compositions and alkaline-surfactant-polymer solutions. Gel solutions under dynamic conditions of linear corefloods showed similar stability to alkaline-surfactant-polymer solutions as in the fluid-fluid analyses. Aluminum-polyacrylamide, flowing gels are not stable to alkaline-surfactant-polymer solutions of either pH 10.5 or 12.9. Chromium acetate-polyacrylamide flowing and rigid flowing gels are stable to subsequent alkaline-surfactant-polymer solution injection. Rigid flowing chromium acetate-polyacrylamide gels maintained permeability reduction better than flowing chromium acetate-polyacrylamide gels. Silicate-polyacrylamide gels are not stable with subsequent injection of either a pH 10.5 or a 12.9 alkaline-surfactant-polymer solution. Neither aluminum citrate-polyacrylamide nor silicate-polyacrylamide gel systems produced significant incremental oil in linear corefloods. Both flowing and rigid flowing chromium acetate-polyacrylamide gels produced incremental oil with the rigid flowing gel producing the greatest amount. Higher oil recovery could have been due to higher differential pressures across cores. None of

  8. Comparing and correlating solubility parameters governing the self-assembly of molecular gels using 1,3:2,4-dibenzylidene sorbitol as the gelator.

    Science.gov (United States)

    Lan, Yaqi; Corradini, Maria G; Liu, Xia; May, Tim E; Borondics, Ferenc; Weiss, Richard G; Rogers, Michael A

    2014-12-02

    Solvent properties play a central role in mediating the aggregation and self-assembly of molecular gelators and their growth into fibers. Numerous attempts have been made to correlate the solubility parameters of solvents and gelation abilities of molecular gelators, but a comprehensive comparison of the most important parameters has yet to appear. Here, the degree to which partition coefficients (log P), Henry's law constants (HLC), dipole moments, static relative permittivities (ε(r)), solvatochromic E(T)(30) parameters, Kamlet-Taft parameters (β, α, and π), Catalan's solvatochromic parameters (SPP, SB, and SA), Hildebrand solubility parameters (δ(i)), and Hansen solubility parameters (δ(p), δ(d), δ(h)) and the associated Hansen distance (R(ij)) of 62 solvents (covering a wide range of properties) can be correlated with the self-assembly and gelation of 1,3:2,4-dibenzylidene sorbitol (DBS) gelation, a classic molecular gelator, is assessed systematically. The approach presented describes the basis for each of the parameters and how it can be applied. As such, it is an instructional blueprint for how to assess the appropriate type of solvent parameter for use with other molecular gelators as well as with molecules forming other types of self-assembled materials. The results also reveal several important insights into the factors favoring the gelation of solvents by DBS. The ability of a solvent to accept or donate a hydrogen bond is much more important than solvent polarity in determining whether mixtures with DBS become solutions, clear gels, or opaque gels. Thermodynamically derived parameters could not be correlated to the physical properties of the molecular gels unless they were dissected into their individual HSPs. The DBS solvent phases tend to cluster in regions of Hansen space and are highly influenced by the hydrogen-bonding HSP, δ(h). It is also found that the fate of this molecular gelator, unlike that of polymers, is influenced not only by

  9. Inhibition and Promotion of Heat-Induced Gelation of Whey Proteins in the Presence of Calcium by Addition of Sodium Caseinate.

    Science.gov (United States)

    Nguyen, Bach T; Balakrishnan, Gireeshkumar; Jacquette, Boris; Nicolai, Taco; Chassenieux, Christophe; Schmitt, Christophe; Bovetto, Lionel

    2016-11-14

    Heat-induced aggregation and gelation of aqueous solutions of whey protein isolate (WPI) in the presence of sodium caseinate (SC) and CaCl 2 was studied at pH 6.6. The effect of adding SC (0-100 g/L) on the structure of the aggregates and the gels was investigated by light scattering and confocal laser scanning microscopy at different CaCl 2 concentration ([CaCl 2 ] = 0-30 mM). The gelation process was studied by oscillatory shear rheology. At the whey protein concentrations studied here (34 and 60 g/L), no gels were formed in the absence of CaCl 2 and SC. However, WPI solutions gelled above a critical CaCl 2 concentration that increased with increasing SC concentration. In the absence of CaCl 2 , WPI gels were formed only above a critical SC concentration. The critical SC concentration needed to induce WPI gelation decreased weakly when CaCl 2 was added. In an intermediate range of CaCl 2 concentrations, gels were formed both at low and high SC concentrations, but not at intermediate SC concentrations. Finally, at high CaCl 2 concentrations gels were formed at all SC concentrations. The gelation rate and the gel structure of the gels formed at low and high casein concentrations were very different. The effect of SC on the thermal gelation of WPI was interpreted by competition for Ca 2+ , a chaperon effect, and microphase separation.

  10. Selection and Evaluation of Electronic Resources Elektronik Kaynakların Seçimi ve Değerlendirilmesi

    Directory of Open Access Journals (Sweden)

    Doğan Atılgan

    2009-12-01

    Full Text Available Publication boom and issues related to controlling and accession of printed sources have created some problems after World War II. Consequently, publishing industry has encountered the problem of finding possible solution for emerged situation. Industry of electronic publishing has started to improve with the rapid increase of the price of printed sources as well as the problem of publication boom. The first effects of electronic publishing were appeared on the academic and scholarly publications then electronic publishing became a crucial part of all types of publications. As a result of these developments, collection developments and service policies of information centers were also significantly changed. In this article, after a general introduction about selection and evaluation processes of electronic publications, the subscribed databases by a state and a privately owned university in Turkey and their usage were examined. İkinci dünya savaşından sonra görülen yayın patlaması, basılı kaynakların denetim ve erişiminde sorunlar yaşanmasına neden olmuştur. Bu da yayıncılık sektöründe yeni arayışlara yol açmıştır. 1980’li yıllardan sonra basılı yayın fiyatlarındaki hızlı artış da bu etmenlere eklenince elektronik yayıncılık sektörü gelişmeye başlamıştır. Öncelikle bilimsel ve akademik yayınlarla başlayan elektronik yayın günümüzde tüm yayın türlerini kapsamaktadır. Yayıncılıktaki bu gelişim bilgi merkezlerinin derme geliştirme ve hizmet politikalarını da önemli ölçüde değiştirmiştir. Bu çalışmada elektronik yayınların seçim, değerlendirme ve sağlama konularında genel bir girişten sonra bir devlet üniversitesinin bir de özel üniversitenin abone olduğu veritabanları ve bu veri tabanlarının kullanımının değerlendirilmesi yapılmaktadır.

  11. Evaluation of some physico-chemical properties of restructured trout and hake mince during cold gelation and chilled storage

    DEFF Research Database (Denmark)

    Moreno, H.M.; Javier Borderias, A.; Baron, Caroline

    2010-01-01

    Cold gelation was carried out on trout (Oncorhynchus mykiss) or on hake (Merluccius mertuccius) mince with or without addition of fish oil and using microbial transglutaminase (MTGase). Products were stored at 4 QC for 6 days and lipid oxidation, protein oxidation, texture, water binding capacity......, and colour were followed. Results indicated that MTGase was able to generate gels with good properties for both trout and hake. Gels prepared with trout were oxidised whilst gels prepared with hake were stable toward oxidation even in the presence of 5% fish oil. However, in the presence of oil...

  12. Utility of the electronic information resource UpToDate for clinical decision-making at bedside rounds.

    Science.gov (United States)

    Phua, J; See, K C; Khalizah, H J; Low, S P; Lim, T K

    2012-02-01

    Clinical questions often arise at daily hospital bedside rounds. Yet, little information exists on how the search for answers may be facilitated. The aim of this prospective study was, therefore, to evaluate the overall utility, including the feasibility and usefulness of incorporating searches of UpToDate, a popular online information resource, into rounds. Doctors searched UpToDate for any unresolved clinical questions during rounds for patients in general medicine and respiratory wards, and in the medical intensive care unit of a tertiary teaching hospital. The nature of the questions and the results of the searches were recorded. Searches were deemed feasible if they were completed during the rounds and useful if they provided a satisfactory answer. A total of 157 UpToDate searches were performed during the study period. Questions were raised by all ranks of clinicians from junior doctors to consultants. The searches were feasible and performed immediately during rounds 44% of the time. Each search took a median of three minutes (first quartile: two minutes, third quartile: five minutes). UpToDate provided a useful and satisfactory answer 75% of the time, a partial answer 17% of the time and no answer 9% of the time. It led to a change in investigations, diagnosis or management 37% of the time, confirmed what was originally known or planned 38% of the time and had no effect 25% of the time. Incorporating UpToDate searches into daily bedside rounds was feasible and useful in clinical decision-making.

  13. Elastin Based Cell-laden Injectable Hydrogels with Tunable Gelation, Mechanical and Biodegradation Properties

    Science.gov (United States)

    Fathi, Ali; Mithieux, Suzanne M.; Wei, Hua; Chrzanowski, Wojciech; Valtchev, Peter; Weiss, Anthony S.; Dehghani, Fariba

    2015-01-01

    Injectable hydrogels made from extracellular matrix proteins such as elastin show great promise for various biomedical applications. Use of cytotoxic reagents, fixed gelling behavior, and lack of mechanical strength in these hydrogels are the main associated drawbacks. The aim of this study was to develop highly cytocompatible and injectable elastin-based hydrogels with alterable gelation characteristics, favorable mechanical properties and structural stability for load bearing applications. A thermoresponsive copolymer, poly(N-isopropylacrylamide-co-polylactide-2-hydroxyethyl methacrylate-co-oligo(ethylene glycol)monomethyl ether methacrylate, was functionalized with succinimide ester groups by incorporating N-acryloxysuccinimide monomer. These ester groups were exploited to covalently bond this polymer, denoted as PNPHO, to different proteins with primary amine groups such as α-elastin in aqueous media. The incorporation of elastin through covalent bond formation with PNPHO promotes the structural stability, mechanical properties and live cell proliferation within the structure of hydrogels. Our results demonstrated that elastin-co-PNPHO solutions were injectable through fine gauge needles and converted to hydrogels in situ at 37 °C in the absence of any crosslinking reagent. By altering PNPHO content, the gelling time of these hydrogels can be finely tuned within the range of 2 to 15 min to ensure compatibility with surgical requirements. In addition, these hydrogels exhibited compression moduli in the range of 40 to 145 kPa, which are substantially higher than those of previously developed elastin-based hydrogels. These hydrogels were highly stable in the physiological environment with the evidence of 10 wt% mass loss in 30 days of incubation in a simulated environment. This class of hydrogels is in vivo bioabsorbable due to the gradual increase of the lower critical solution temperature of the copolymer to above 37 °C due to the cleavage of polylactide from

  14. Insights into the mechanical properties of a silicone oil gel with a ‘latent’ gelator, 1-octadecylamine, and CO2 as an ‘activator’

    Directory of Open Access Journals (Sweden)

    Emiliano Carretti

    2010-10-01

    Full Text Available A detailed study of the rheological properties of silicone oil gels, made from a low-molecular-mass organic gelator, a combination of 1-octadecylamine (a latent gelator and carbon dioxide (an ‘activating’ molecule, is reported. Information gleaned from the mechanical measurements is used to characterize the gel networks and how they respond to temperature and strain. It is shown, for example, that very precise measurements of the gel-to-sol transitions can be obtained from plots of viscosity versus temperature.

  15. Supra-dendron Gelator Based on Azobenzene-Cyclodextrin Host-Guest Interactions: Photoswitched Optical and Chiroptical Reversibility.

    Science.gov (United States)

    Xie, Fan; Ouyang, Guanghui; Qin, Long; Liu, Minghua

    2016-12-12

    A novel amphiphilic dendron (AZOC 8 GAc) with three l-glutamic acid units and an azobenzene moiety covalently linked by an alkyl spacer has been designed. The compound formed hydrogels with water at very low concentration and self-assembled into chiral-twist structures. The gel showed a reversible macroscopic volume phase transition in response to pH variations and photo-irradiation. During the photo-triggered changes, although the gel showed complete reversibility in its optical absorptions, only an incomplete chiroptical property change was achieved. On the other hand, the dendron could form a 1:1 inclusion complex through a host-guest interaction with α-cyclodextrin (α-CD), designated as supra-dendron gelator AZOC 8 GAc/α-CD. The supra-dendron showed similar gelation behavior to that of AZOC 8 GAc, but with enhanced photoisomerization-transition efficiency and chiroptical switching capacity, which was completely reversible in terms of both optical and chiroptical performances. The self-assembly of the supra-dendron is a hierarchical or multi-supramolecular self-assembling process. This work has clearly illustrated that the hierarchical and multi-supramolecular self-assembling system endows the supramolecular nanostructures or materials with superior reversible optical and chiroptical switching. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  16. Preparation and characterization of monodisperse microcapsules with alginate and bentonite via external gelation technique encapsulating Pseudomonas putida Rs-198.

    Science.gov (United States)

    Li, Xuan; Wu, Zhansheng; He, Yanhui; Ye, Bang-Ce; Wang, Jun

    2017-10-01

    This paper evaluated the external gelation technique for preparing microcapsules. The microcapsules were consisted of Pseudomonas putida Rs-198 (Rs-198) core and sodium alginate (NaAlg)-bentonite (Bent) shell. Different emulsification rotation speeds and core/shell ratios were used to prepare the microcapsules of each formulation. The near-spherical microcapsules were monodisperse with a mean diameter of 25-100 μm and wrinkled surfaces. Fourier transform infrared spectrophotometry (FTIR) and thermogravimetric analysis (TGA) revealed the physical mixture of the wall material and the superior thermal stability of the microcapsules. Percentage yield, water content, and encapsulation efficiency were evaluated and correlated with the changes in emulsification rotation speed and core/shell ratio. In vitro release experiments demonstrated that 60% of the bacteria were released from the NaAlg-Bent microcapsules within three days. Considerably better survival was observed for encapsulated cells compared to free cells, especially in pH 4.0 and 10.0. In summary, the desired properties of microcapsules can be obtained by external gelation technique and the microcapsules on the bacteria had a good protective effect.

  17. Preparation of collagen peptide functionalized chitosan nanoparticles by ionic gelation method: An effective carrier system for encapsulation and release of doxorubicin for cancer drug delivery

    Energy Technology Data Exchange (ETDEWEB)

    Anandhakumar, S., E-mail: rsanandhakumar@gmail.com [SRM Research Institute, SRM University, Kattankulathur, Chennai 603203 (India); Krishnamoorthy, G.; Ramkumar, K.M. [SRM Research Institute, SRM University, Kattankulathur, Chennai 603203 (India); Raichur, A.M. [Department of Materials Engineering, Indian Institute of Science, Bangalore 560012 (India)

    2017-01-01

    In recent years, nanoparticles (NPs) based on biopolymers or peptides are gaining popularity for the encapsulation and release of drug molecules, especially for cancer therapy, due to their ability for targeted and controlled release. The use of collagen peptide (CP) for the preparation of chitosan (CN) NPs is especially interesting as it results in NPs that are stable under physiological conditions. In this work, mono-dispersed pH responsive CPCN NPs of about 100 nm were prepared via ionic gelation method by simple and mild co-precipitation of CN and CP. Investigation of NPs with Fourier transform infra-red (FTIR) spectroscopy and dynamic light scattering (DLS) measurements reveals that hydrogen bonding and electrostatic interactions are believed to be major driving forces for NP formation and drug encapsulation, respectively. Scanning electron microscopic (SEM) investigations show that hard and fine CPCN NPs transform to soft and bigger gel like particles as a function of collagen concentration. The unique “polymeric gel” structure of NPs showed high encapsulation efficiency towards doxorubicin hydrochloride (DOX) as well as pH controlled release. Anti-proliferative and cell viability analysis revealed that DOX loaded NPs showed excellent anti-proliferative characteristics against HeLa cells with favorable biocompatibility against normal cells. Such NPs have high potential for use as smart drug delivery carriers in advanced cancer therapy. - Highlights: • Preparation of collagen peptide functionalized chitosan nanoparticles • Hydrogen bonding plays a key role in particle formation. • Electrostatic interaction plays a key role in drug encapsulation. • Functionalized chitosan particles are more stable than chitosan NPs.

  18. Comprehensive evaluation of electronic medical record system use and user satisfaction at five low-resource setting hospitals in ethiopia.

    Science.gov (United States)

    Tilahun, Binyam; Fritz, Fleur

    2015-05-25

    Electronic medical record (EMR) systems are increasingly being implemented in hospitals of developing countries to improve patient care and clinical service. However, only limited evaluation studies are available concerning the level of adoption and determinant factors of success in those settings. The objective of this study was to assess the usage pattern, user satisfaction level, and determinants of health professional's satisfaction towards a comprehensive EMR system implemented in Ethiopia where parallel documentation using the EMR and the paper-based medical records is in practice. A quantitative, cross-sectional study design was used to assess the usage pattern, user satisfaction level, and determinant factors of an EMR system implemented in Ethiopia based on the DeLone and McLean model of information system success. Descriptive statistical methods were applied to analyze the data and a binary logistic regression model was used to identify determinant factors. Health professionals (N=422) from five hospitals were approached and 406 responded to the survey (96.2% response rate). Out of the respondents, 76.1% (309/406) started to use the system immediately after implementation and user training, but only 31.7% (98/309) of the professionals reported using the EMR during the study (after 3 years of implementation). Of the 12 core EMR functions, 3 were never used by most respondents, and they were also unaware of 4 of the core EMR functions. It was found that 61.4% (190/309) of the health professionals reported over all dissatisfaction with the EMR (median=4, interquartile range (IQR)=1) on a 5-level Likert scale. Physicians were more dissatisfied (median=5, IQR=1) when compared to nurses (median=4, IQR=1) and the health management information system (HMIS) staff (median=2, IQR=1). Of all the participants, 64.4% (199/309) believed that the EMR had no positive impact on the quality of care. The participants indicated an agreement with the system and information

  19. Coupling the Alkaline-Surfactant-Polymer Technology and The Gelation Technology to Maximize Oil Production

    Energy Technology Data Exchange (ETDEWEB)

    Malcolm Pitts; Jie Qi; Dan Wilson; Phil Dowling; David Stewart; Bill Jones

    2005-12-01

    Gelation technologies have been developed to provide more efficient vertical sweep efficiencies for flooding naturally fractured oil reservoirs or reservoirs with different sand lenses with high permeability contrast. The field proven alkaline-surfactant-polymer technology economically recovers 15% to 25% OOIP more crude oil than waterflooding from swept pore space of an oil reservoir. However, alkaline-surfactant-polymer technology is not amenable to naturally fractured reservoirs or reservoirs with high permeability contrast zones because much of injected solution bypasses target pore space containing oil. This work investigates whether combining these two technologies could broaden applicability of alkaline-surfactant-polymer flooding into these reservoirs. Fluid-fluid interaction with different gel chemical compositions and alkaline-surfactant-polymer solution with pH values ranging from 9.2 to 12.9 have been tested. Aluminum-polyacrylamide gels are not stable to alkaline-surfactant-polymer solutions at any pH. Chromium-polyacrylamide gels with polymer to chromium ion ratios of 25 or greater were stable to alkaline-surfactant-polymer solutions if solution pH was 10.6 or less. When the polymer to chromium ion was 15 or less, chromium-polyacrylamide gels were stable to alkaline-surfactant-polymer solutions with pH values up to 12.9. Chromium-xanthan gum gels were stable to alkaline-surfactant-polymer solutions with pH values of 12.9 at the polymer to chromium ion ratios tested. Silicate-polyacrylamide, resorcinol-formaldehyde, and sulfomethylated resorcinol-formaldehyde gels were also stable to alkaline-surfactant-polymer solutions with pH values ranging from 9.2 to 12.9. Iron-polyacrylamide gels were immediately destroyed when contacted with any of the alkaline-surfactant-polymer solutions with pH values ranging from 9.2 to 12.9. Gel solutions under dynamic conditions of linear corefloods showed similar stability to alkaline-surfactant-polymer solutions as in

  20. Randomized Controlled Trial of Electronic Care Plan Alerts and Resource Utilization by High Frequency Emergency Department Users with Opioid Use Disorder

    Directory of Open Access Journals (Sweden)

    Niels Rathlev, MD

    2016-01-01

    Full Text Available Introduction: There is a paucity of literature supporting the use of electronic alerts for patients with high frequency emergency department (ED use. We sought to measure changes in opioid prescribing and administration practices, total charges and other resource utilization using electronic alerts to notify providers of an opioid-use care plan for high frequency ED patients. Methods: This was a randomized, non-blinded, two-group parallel design study of patients who had 1 opioid use disorder and 2 high frequency ED use. Three affiliated hospitals with identical electronic health records participated. Patients were randomized into “Care Plan” versus “Usual Care groups”. Between the years before and after randomization, we compared as primary outcomes the following: 1 opioids (morphine mg equivalents prescribed to patients upon discharge and administered to ED and inpatients; 2 total medical charges, and the numbers of; 3 ED visits, 4 ED visits with advanced radiologic imaging (computed tomography [CT] or magnetic resonance imaging [MRI] studies, and 5 inpatient admissions. Results: A total of 40 patients were enrolled. For ED and inpatients in the “Usual Care” group, the proportion of morphine mg equivalents received in the post-period compared with the pre-period was 15.7%, while in the “Care Plan” group the proportion received in the post-period compared with the pre-period was 4.5% (ratio=0.29, 95% CI [0.07-1.12]; p=0.07. For discharged patients in the “Usual Care” group, the proportion of morphine mg equivalents prescribed in the post-period compared with the pre-period was 25.7% while in the “Care Plan” group, the proportion prescribed in the post-period compared to the pre-period was 2.9%. The “Care Plan” group showed an 89% greater proportional change over the periods compared with the “Usual Care” group (ratio=0.11, 95% CI [0.01-0.092]; p=0.04. Care plans did not change the total charges, or, the numbers

  1. There is a Relationship between Resource Expenditures and Reference Transactions in Academic Libraries. A Review of: Dubnjakovic, A. (2012. Electronic resource expenditure and the decline in reference transaction statistics in academic libraries. Journal of Academic Librarianship, 38(2, 94-100. doi:10.1016/j.acalib.2012.01.001

    Directory of Open Access Journals (Sweden)

    Annie M. Hughes

    2013-03-01

    Full Text Available Objective – To provide an analysis of the impact of expenditures on electronic resourcesand gate counts on the increase or decrease in reference transactions.Design – Analysis of results of existing survey data from the National Center for Educational Statistics (NCES 2006 Academic Library Survey(ALS.Setting – Academic libraries in the United States.Subjects – 3925 academic library respondents.Methods – The author chose to use survey data collected from the 2006 ALS conducted bythe NCES. The survey included data on various topics related to academic libraries, but in the case of this study, the author chose to analyze three of the 193 variables included. The three variables: electronic books expenditure, computer hardware and software, and expenditures on bibliographic utilities, were combined into one variable called electronic resource expenditure. Gate counts were also considered as a variable. Electronic resource expenditure was also split as a variable into three groups: low, medium, and high. Multiple regression analysis and general linear modeling, along with tests of reliability, were employed. Main Results – The author determined that low, medium, and high spenders with regard to electronic resources exhibited differences in gate counts, and gate counts have an effect on reference transactions in any given week. Gate counts tend to not have much of an effect on reference transactions for the higher spenders, and higher spenders tend to have a higher number of reference transactions overall. Low spenders have lower gate counts and also a lower amount of reference transactions.Conclusion – The findings from this study show that academic libraries spending more on electronic resources also tend to have an increase with regard to reference transactions. The author also concludes that library spaces are no longer the determining factor with regard to number of reference transactions. Spending more on electronic resources is

  2. Global application of disorders of sex development-related electronic resources: e-learning, e-consultation and e-information sharing.

    Science.gov (United States)

    Muscarella, Miriam; Kranenburg-van Koppen, Laura; Grijpink-van den Biggelaar, Kalinka; Drop, Stenvert L S

    2014-01-01

    The past 20 years have seen proliferation of electronic (e) resources that promote improved understanding of disorders of sex development (DSD): e-learning for physicians and trainees, e-consultation between clinicians, and e-information for families and affected individuals. Recent e-learning advances have emerged from the European Society for Pediatric Endocrinology's online learning portal for current physicians and trainees. Developed with attention to developing clinical competencies incorporating learning theory, and presenting material that represents international best practice, this e-learning portal offers advances in training, making information more accessible for clinicians and trainees. Multiple levels of instruction, authentic case examples, collaborative forums for physicians and trainees, individualized feedback and user-friendly tools represent advances in trainee and physician learning that can take place in any location. e-consultation is an emerging tool that aims to connect physicians with specialists experienced in DSD care. Although it faces logistical challenges, e-consultation carries the potential to improve DSD care, especially in remote areas with limited access to DSD specialists. e-information for families and patients of all ages is widely accessible online, often with focus on DSD biology, medical care, and psychological and social support. e-information tools aid self-management and support of those affected by DSD. Efforts to improve these resources should aim to map information to individual users, incorporate optimally clear nomenclature, and continue as a 'shared enterprise' of clinicians, affected individuals, families and researchers. Improving the quality of DSD-related e-learning and e-information and developing e-consultation carries the potential to transform DSD care and support for patients, families and physicians worldwide. © 2014 S. Karger AG, Basel.

  3. A comparative study of nitride purity and Am fabrication losses in PuN materials by the powder and internal gelation production routes

    Energy Technology Data Exchange (ETDEWEB)

    Hedberg, Marcus, E-mail: marhed@chalmers.se; Ekberg, Christian

    2016-12-15

    Fabrication of plutonium containing fuels through the internal gelation method has mostly been studied in mixed metal systems such as U, Pu or Zr,Pu. In this work production of undiluted PuN has been performed by carbothermal reduction on both oxide powder and Pu microspheres produced by the internal gelation method. Nitride purities reached using the different methods have been studied together with final densities achieved during pellet fabrication as well as losses of ingrown Am during the different production steps. Formation of Pu microspheres was successfully performed using the internal gelation method, although extensive microsphere fracturing occurred during thermal treatment. Final densities of PuN pellets produced by cold pressing and sintering reached 70–80% of theoretical density. Am losses during the carbothermal reduction step was on average about 3.7%. After sintering about 11% of Am was lost in total through the entire production process if sintering in N{sub 2} + 5% H{sub 2} atmosphere while about 50% of the Am in total was lost when using Ar as sintering atmosphere. - Highlights: • Internal gelation Pu based sols was performed. • Nitride formation by carbothermal reduction on Pu microspheres and powders was performed. • Pelletization and sintering of pellets was performed. • Am losses were measured throughout the production steps.

  4. Gelation Behavior Study of a Resorcinol–Hexamethyleneteramine Crosslinked Polymer Gel for Water Shut-Off Treatment in Low Temperature and High Salinity Reservoirs

    Directory of Open Access Journals (Sweden)

    Yongpeng Sun

    2017-07-01

    Full Text Available Mature oilfields usually encounter the problem of high watercut. It is practical to use chemical methods for water-shutoff in production wells, however conventional water-shutoff agents have problems of long gelation time, low gel strength, and poor stability under low temperature and high salinity conditions. In this work a novel polymer gel for low temperature and high salinity reservoirs was developed. This water-shutoff agent had controllable gelation time, adjustable gel strength and good stability performance. The crosslinking process of this polymer gel was studied by rheological experiments. The process could be divided into an induction period, a fast crosslinking period, and a stable period. Its gelation behaviors were investigated in detail. According to the Gel Strength Code (GSC and vacuum breakthrough method, the gel strength was displayed in contour maps. The composition of the polymer gel was optimized to 0.25~0.3% YG100 + 0.6~0.9% resorcinol + 0.2~0.4% hexamethylenetetramine (HMTA + 0.08~0.27% conditioner (oxalic acid. With the concentration increase of the polymer gel and temperature, the decrease of pH, the induction period became shorter and the crosslinking was more efficient, resulting in better stability performance. Various factors of the gelation behavior which have an impact on the crosslinking reaction process were examined. The relationships between each impact factor and the initial crosslinking time were described with mathematical equations.

  5. New models of radical polymerization with branching and scission predicting molecular weight distribution in tubular and series of continuous stirred tank reactors allowing for multiradicals and gelation

    NARCIS (Netherlands)

    Yaghini, N.; Iedema, P.D.

    2015-01-01

    Modeling of the mol. wt. distribution (MWD) of low-​d. Polyethylene (ldPE) has been carried out for a tubular reactor under realistic non-​isothermal conditions and for a series of CSTR's. The model allows for the existence of multiradicals and the occurrence of gelation. The deterministic model is

  6. Gelation of Oil upon Contact with Water: A Bioinspired Scheme for the Self-Repair of Oil Leaks from Underwater Tubes.

    Science.gov (United States)

    Oh, Hyuntaek; Yaraghi, Nicholas; Raghavan, Srinivasa R

    2015-05-19

    Molecular organogelators convert oils into gels by forming self-assembled fibrous networks. Here, we demonstrate that such gelation can be activated by contacting the oil with an immiscible solvent (water). Our gelator is dibenzylidene sorbitol (DBS), which forms a low-viscosity sol when added to toluene containing a small amount of dimethyl sulfoxide (DMSO). Upon contact with water, DMSO partitions into the water, activating gelation of DBS in the toluene. The gel grows from the oil/water interface and slowly envelops the oil phase. We have exploited this effect for the self-repair of oil leaks from underwater tubes. When a DBS/toluene/DMSO solution flows through the tube, it forms a gel selectively at the leak point, thereby plugging the leak and restoring flow. Our approach is reminiscent of wound-sealing via blood-clotting: there also, inactive gelators in blood are activated at the wound site into a fibrous network, thereby plugging the wound and restoring blood flow.

  7. Effect of extraction pH on heat-induced aggregation, gelation and microstructure of protein isolate from quinoa (Chenopodium quinoa Willd)

    NARCIS (Netherlands)

    Ruiz, Geraldine Avila; Xiao, Wukai; Boekel, van Tiny; Minor, Marcel; Stieger, Markus

    2016-01-01

    The aim of this study was to determine the influence of extraction pH on heat-induced aggregation, gelation and microstructure of suspensions of protein isolates extracted from quinoa (Chenopodium quinoa Willd). Quinoa seed protein was extracted by alkaline treatment at various pH values (pH 8

  8. Ranking Medical Terms to Support Expansion of Lay Language Resources for Patient Comprehension of Electronic Health Record Notes: Adapted Distant Supervision Approach.

    Science.gov (United States)

    Chen, Jinying; Jagannatha, Abhyuday N; Fodeh, Samah J; Yu, Hong

    2017-10-31

    Medical terms are a major obstacle for patients to comprehend their electronic health record (EHR) notes. Clinical natural language processing (NLP) systems that link EHR terms to lay terms or definitions allow patients to easily access helpful information when reading through their EHR notes, and have shown to improve patient EHR comprehension. However, high-quality lay language resources for EHR terms are very limited in the public domain. Because expanding and curating such a resource is a costly process, it is beneficial and even necessary to identify terms important for patient EHR comprehension first. We aimed to develop an NLP system, called adapted distant supervision (ADS), to rank candidate terms mined from EHR corpora. We will give EHR terms ranked as high by ADS a higher priority for lay language annotation-that is, creating lay definitions for these terms. Adapted distant supervision uses distant supervision from consumer health vocabulary and transfer learning to adapt itself to solve the problem of ranking EHR terms in the target domain. We investigated 2 state-of-the-art transfer learning algorithms (ie, feature space augmentation and supervised distant supervision) and designed 5 types of learning features, including distributed word representations learned from large EHR data for ADS. For evaluating ADS, we asked domain experts to annotate 6038 candidate terms as important or nonimportant for EHR comprehension. We then randomly divided these data into the target-domain training data (1000 examples) and the evaluation data (5038 examples). We compared ADS with 2 strong baselines, including standard supervised learning, on the evaluation data. The ADS system using feature space augmentation achieved the best average precision, 0.850, on the evaluation set when using 1000 target-domain training examples. The ADS system using supervised distant supervision achieved the best average precision, 0.819, on the evaluation set when using only 100 target

  9. Impact of two interventions on timeliness and data quality of an electronic disease surveillance system in a resource limited setting (Peru: a prospective evaluation

    Directory of Open Access Journals (Sweden)

    Quispe Jose A

    2009-03-01

    Full Text Available Abstract Background A timely detection of outbreaks through surveillance is needed in order to prevent future pandemics. However, current surveillance systems may not be prepared to accomplish this goal, especially in resource limited settings. As data quality and timeliness are attributes that improve outbreak detection capacity, we assessed the effect of two interventions on such attributes in Alerta, an electronic disease surveillance system in the Peruvian Navy. Methods 40 Alerta reporting units (18 clinics and 22 ships were included in a 12-week prospective evaluation project. After a short refresher course on the notification process, units were randomly assigned to either a phone, visit or control group. Phone group sites were called three hours before the biweekly reporting deadline if they had not sent their report. Visit group sites received supervision visits on weeks 4 & 8, but no phone calls. The control group sites were not contacted by phone or visited. Timeliness and data quality were assessed by calculating the percentage of reports sent on time and percentage of errors per total number of reports, respectively. Results Timeliness improved in the phone group from 64.6% to 84% in clinics (+19.4 [95% CI, +10.3 to +28.6]; p Conclusion Regular phone reminders significantly improved timeliness of reports in clinics and ships, whereas supervision visits led to improved data quality only among clinics. Further investigations are needed to establish the cost-effectiveness and optimal use of each of these strategies.

  10. Micellizationa and Gelation of Water Soluable Thermo-and Light-sensitive Block Copolymer Investigated by SANS

    Science.gov (United States)

    He, Lilin; Hu, Bin; Zhao, Bin

    2015-03-01

    Here we present an extensive small-angle neutron scattering (SANS) characterization of micellization and gelation of PEO-b-P(TEGEA-co-NBA) in deuterated water in a wide range of temperatures and concentrations before and after the removal of o-nitrobenzyl group by UV irradiation. Scattering data analysis indicated that unimers predominated in the solutions at low temperatures and concentrations. The polymer self-assembled into micelles with the P(TEGEA-co-NBA) block packed into the core and PEO forming the corona layer. A core-shell model was used to fit SANS data and obtain sizes and scattering length densities. Structural parameters such as the aggregation numbers, the radius of gyration of the chains in the shell region, the number of water molecules in the both regions were determined. The structural information combined with the rheological data were used to describe the phase behaviors of the diblock copolymer in aqueous solution.

  11. Production and characterization of alginate-starch-chitosan microparticles containing stigmasterol through the external ionic gelation technique

    Directory of Open Access Journals (Sweden)

    Gislene Mari Fujiwara

    2013-09-01

    Full Text Available Stigmasterol - a plant sterol with several pharmacological activities - is susceptible to oxidation when exposed to air, a process enhanced by heat and humidity. In this context, microencapsulation is a way of preventing oxidation, allowing stigmasterol to be incorporated into various pharmaceutical forms while increasing its absorption. Microparticles were obtained using a blend of polymers of sodium alginate, starch and chitosan as the coating material through a one-stage process using the external gelation technique. Resultant microparticles were spherical, averaging 1.4 mm in size. Encapsulation efficiency was 90.42% and method yield 94.87%. The amount of stigmasterol in the oil recovered from microparticles was 9.97 mg/g. This technique proved feasible for the microencapsulation of stigmasterol.

  12. Influent of Carbonization of Sol Solution at the External Gelation Process on the Quality of Uranium Oxide Kernel

    International Nuclear Information System (INIS)

    Damunir; Sukarsono

    2007-01-01

    The influent of carbonization of sol solution at the external gelation process on the quality of uranium oxide kernel was done. Variables observed are the influent of carbon, temperature and time of reduction process of U 3 O 8 kernel resulted from carbonization of sol solution. First of all, uranyl nitrate was reacted with 1 M NH 4 OH solution, producing the colloid of UO 3 . Then by mixing and heating up to the temperature of 60-80 °C, the colloid solution was reacted with PVA, mono sorbitol oleate and paraffin producing of uranium-PVA sol. Then sol solution was carbonized with carbon black of mol ratio of carbon to uranium =2.32-6.62, produce of carbide gel. Gel then washed, dried and calcined at 800 °C for 4 hours to produce of U 3 O 8 kernel containing carbon. Then the kernel was reduced by H 2 gas in the medium of N 2 gas at 500-800 °C, 50 mmHg pressure for 3 hours. The process was repeated at 700 °C, 50 mmHg pressure for 1-4 hours. The characterization of chemical properties of the gel grains and uranium oxide kernel using FTIR covering the analysis of absorption band of infra red spectrum of UO 3 , C-OH, NH 3 , C-C, C-H and OH functional group. The physical properties of uranium oxide covering specific surface area, void volume, mean diameter using surface area meter Nova-1000 and as N 2 gas an absorbent. And O/U ratio of uranium dioxide kernel by gravimetry method. The result of experiment showed that carbonization of sol solution at the external gelation process give influencing the quality of uranium oxide kernel. (author)

  13. Gelation of high-methoxy pectin by enzymic de-esterification in the presence of calcium ions: a preliminary evaluation.

    Science.gov (United States)

    O'Brien, Aileen B; Philp, Kevin; Morris, Edwin R

    2009-09-28

    Cohesive gels have been obtained by de-esterification of 1.0wt% high-methoxy citrus pectin (degree of esterification approximately 68%) in the presence of Ca(2+) cations, using a commercial preparation (NovoShape) of fungal methyl esterase cloned from Aspergillus aculeatus. A convenient rate of network formation (gelation within approximately 30min) was achieved at an enzyme concentration of 0.2 PEU/g pectin. At a Ca(2+)-concentration of 40mM and incubation temperature of 20 degrees C, severe syneresis (>7% of sample mass) was observed, but release of fluid decreased with decreasing concentration of Ca(2+) and increasing temperature of incubation, becoming undetectable for 10mM Ca(2+) at 30 degrees C. Under these conditions, progressive development of solid-like character (storage modulus, G') was observed during 160min of enzymic de-esterification, and the mechanical spectrum recorded at the end of the incubation period had the form typical of a biopolymer gel. On subsequent heating to 70 degrees C, dissociation of the gel network (sigmoidal reduction in G' and G'') was observed. At or above the midpoint temperature of this melting process ( approximately 50 degrees C), there was no indication of gel formation on enzymic de-esterification (at 50 or 60 degrees C). At lower temperatures (20, 30 and 40 degrees C), the rate of gelation (assessed visually) showed no systematic increase as the incubation temperature was increased towards the temperature-optimum of the enzyme ( approximately 50 degrees C). This unexpected behaviour is attributed to competition between faster de-esterification and slower formation of Ca(2+)-induced 'egg-box' junctions.

  14. Fabrication and Characterization of Device Pressure Regulation System Orifice of Manufacturing Process Gel Uranium Column Gelation External

    International Nuclear Information System (INIS)

    Triyono; Sutarni; Indra Suryawan

    2009-01-01

    The device pressure regulation orifice system of manufacturing process gel uranium on external column gelation has been made and characterized. The device consists : compressor 5.75-6.75 kg / cm 2 , air container tank, power supply 24 volts dc, solenoid valve 24 volts dc, pressure indicator 0-100 mbar, pressure indicator 0-250 mbar, mechanical valve and power electric 380 volts 50 Hz. The activity includes: installation device system and characterization with pressure variation orifice 5-75 mbar on the compressor 5.75-6.5 kg/cm 2 continuously for 1 minute. The method of installation i.e: wiring and piping to first component and support component (compressor and pressure air indicator, air container tank and pressure air indicator, solenoid valve, power supply 220 volts / 24 volts dc and orifice). After apparatus installed has been tested by the characterization without feed under air pressure varied to orifice of 5-75 mbar and device characterization with variation diameter orifice of 0.5-1 mm and orifice pressure of 5-75 mbar. The result in the characterization an every component good function, can be operation by input pressure range of 15-185 mbar orifice pressure range of 5-75 mbar. The characterization result device pressure regulation orifice system showed that: the system can be good operation of air pressure regulation orifice between 5-75 mbar with diameter orifice 0.5 mm to result gelation range of 10-25 piece / minute with variation air pressure input between 15-185 mbar of air pressure compressor 5.75-6.5 kg cm 2 . (author)

  15. Biological Effects of Drug-Free Alginate Beads Cross-Linked by Copper Ions Prepared Using External Ionotropic Gelation.

    Science.gov (United States)

    Pavelková, M; Kubová, K; Vysloužil, J; Kejdušová, M; Vetchý, D; Celer, V; Molinková, D; Lobová, D; Pechová, A; Vysloužil, J; Kulich, P

    2017-05-01

    External ionotropic gelation offers a unique possibility to entrap multivalent ions in a polymer structure. The aim of this experimental study was to prepare new drug-free sodium alginate (ALG) particles cross-linked by Cu 2+ ions and to investigate their technological parameters (particle size, sphericity, surface topology, swelling capacity, copper content, release of Cu 2+ ions, mucoadhesivity) and biological activity (cytotoxicity and efficiency against the most common vaginal pathogens-Herpes simplex, Escherichia coli, Candida albicans) with respect to potential vaginal administration. Beads prepared from NaALG dispersions (3 or 4%) were cross-linked by Cu 2+ ions (0.5 or 1.0 M CuCl 2 ) using external ionotropic gelation. Prepared mucoadhesive beads with particle size over 1000 μm exhibited sufficient sphericity (all ˃0.89) and copper content (214.8-249.07 g/kg), which increased with concentration of polymer and hardening solution. Dissolution behaviour was characterized by extended burst effect, followed by 2 h of copper release. The efficiency of all samples against the most common vaginal pathogens was observed at cytotoxic Cu 2+ concentrations. Anti-HSV activity was demonstrated at a Cu 2+ concentration of 546 mg/L. Antibacterial activity of beads (expressed as minimum inhibition concentration, MIC) was influenced mainly by the rate of Cu 2+ release which was controlled by the extent of swelling capacity. Lower MIC values were found for E. coli in comparison with C. albicans. Sample ALG-3_1.0 exhibited the fastest copper release and was proved to be the most effective against both bacteria. This could be a result of its lower polymer concentration in combination with smaller particle size and thus larger surface area.

  16. Coupling the Alkaline-Surfactant-Polymer Technology and the Gelation Technology to Maximize Oil Production

    Energy Technology Data Exchange (ETDEWEB)

    Malcolm Pitts; Jie Qi; Dan Wilson; Phil Dowling; David Stewart; Bill Jones

    2005-12-01

    Gelation technologies have been developed to provide more efficient vertical sweep efficiencies for flooding naturally fractured oil reservoirs or reservoirs with different sand lenses with high permeability contrast. The field proven alkaline-surfactant-polymer technology economically recovers 15% to 25% OOIP more crude oil than waterflooding froin swept pore space of an oil reservoir. However, alkaline-surfactant-polymer technology is not amenable to naturally fractured reservoirs or reservoirs with high permeability contrast zones because much of injected solution bypasses target pore space containing oil. This work investigates whether combining these two technologies could broaden applicability of alkaline-surfactant-polymer flooding into these reservoirs. Fluid-fluid interaction with different gel chemical compositions and alkaline-surfactant-polymer solution with pH values ranging from 9.2 to 12.9 have been tested. Aluminum-polyacrylamide gels are not stable to alkaline-surfactant-polymer solutions at any pH. Chromium-polyacrylamide gels with polymer to chromium ion ratios of 25 or greater were stable to alkaline-surfactant-polymer solutions if solution pH was 10.6 or less. When the polymer to chromium ion was 15 or less, chromium-polyacrylamide gels were stable to alkaline-surfactant-polymer solutions with pH values up to 12.9. Chromium-xanthan gum gels were stable to alkaline-surfactant-polymer solutions with pH values of 12.9 at the polymer to chromium ion ratios tested. Silicate-polyacrylamide, resorcinol-formaldehyde, and sulfomethylated resorcinol-formaldehyde gels were also stable to alkaline-surfactant-polymer solutions with pH values ranging from 9.2 to 12.9. Iron-polyacrylamide gels were immediately destroyed when contacted with any of the alkaline-surfactant-polymer solutions with pH values ranging from 9.2 to 12.9. Gel solutions under dynamic conditions of linear corefloods showed similar stability to alkaline-surfactant-polymer solutions as in

  17. Online Resources

    Indian Academy of Sciences (India)

    Home; Journals; Journal of Genetics; Online Resources. Journal of Genetics. Online Resources. Volume 97. 2018 | Online resources. Volume 96. 2017 | Online resources. Volume 95. 2016 | Online resources. Volume 94. 2015 | Online resources. Volume 93. 2014 | Online resources. Volume 92. 2013 | Online resources ...

  18. Interactive Electronic Decision Trees for the Integrated Primary Care Management of Febrile Children in Low Resource Settings - Review of existing tools.

    Science.gov (United States)

    Keitel, Kristina; D'Acremont, Valérie

    2018-04-20

    The lack of effective, integrated diagnostic tools pose a major challenge to the primary care management of febrile childhood illnesses. These limitations are especially evident in low-resource settings and are often inappropriately compensated by antimicrobial over-prescription. Interactive electronic decision trees (IEDTs) have the potential to close these gaps: guiding antibiotic use and better identifying serious disease. This narrative review summarizes existing IEDTs, to provide an overview of their degree of validation, as well as to identify gaps in current knowledge and prospects for future innovation. Structured literature review in PubMed and Embase complemented by google search and contact with developers. Six integrated IEDTs were identified: three (eIMCI, REC, and Bangladesh digital IMCI) based on Integrated Management of Childhood Illnesses (IMCI); four (SL eCCM, MEDSINC, e-iCCM, and D-Tree eCCM) on Integrated Community Case Management (iCCM); two (ALMANACH, MSFeCARE) with a modified IMCI content; and one (ePOCT) that integrates novel content with biomarker testing. The types of publications and evaluation studies varied greatly: the content and evidence-base was published for two (ALMANACH and ePOCT), ALMANACH and ePOCT were validated in efficacy studies. Other types of evaluations, such as compliance, acceptability were available for D-Tree eCCM, eIMCI, ALMANACH. Several evaluations are still ongoing. Future prospects include conducting effectiveness and impact studies using data gathered through larger studies to adapt the medical content to local epidemiology, improving the software and sensors, and Assessing factors that influence compliance and scale-up. IEDTs are valuable tools that have the potential to improve management of febrile children in primary care and increase the rational use of diagnostics and antimicrobials. Next steps in the evidence pathway should be larger effectiveness and impact studies (including cost analysis) and

  19. Library resources on the Internet

    Science.gov (United States)

    Buchanan, Nancy L.

    1995-07-01

    Library resources are prevalent on the Internet. Library catalogs, electronic books, electronic periodicals, periodical indexes, reference sources, and U.S. Government documents are available by telnet, Gopher, World Wide Web, and FTP. Comparatively few copyrighted library resources are available freely on the Internet. Internet implementations of library resources can add useful features, such as full-text searching. There are discussion lists, Gophers, and World Wide Web pages to help users keep up with new resources and changes to existing ones. The future will bring more library resources, more types of library resources, and more integrated implementations of such resources to the Internet.

  20. Gelation Behavior of 5-Chloro-8-hydroxyquinoline, an Antituberculosis Agent in Aqueous Alcohol Solutions

    Directory of Open Access Journals (Sweden)

    Jukka Korpela

    2012-09-01

    Full Text Available It was shown that 5-chloro-8-hydroxyquinoline, an antituberculosis agent, gels aqueous alcohol solutions efficiently. Thermal stability and gel-to-sol transition temperature of 1% gel in CD3OD/D2O (2:1 was studied by 1H-NMR. Fibrous structures of four xerogels have been characterized by scanning electron microscope.

  1. The influence of Uranium-Thorium ratio and heating time during gelation using as a CCl4(NH3) on the Gel quality

    International Nuclear Information System (INIS)

    Indra-Suryawan; Sukarsono, R; Setyo-Sulardi

    1996-01-01

    Gel has been prepared from a uranium-thorium sol using CCI 4 (NH 3 ) as a gelling medium. The uranium-thorium ratio and the heating time during gelation have been chosen as variables. The sol was prepared by mixing Th(NO 3 ) 4 and UO 2 (NO 3 ) 2 solutions, heating the solution at 95 o C and adding NH 4 OH solution drop by drop until colloidal particles were formed. Sol was then fed into a gelation column containing CCI 4 (NH 3 ), where the sol was transformed into gel. A good gel has properties such as sphere in shape and elastic which it will not crack when it is dropped from 2 metres height. The experimental work resulted a good gel when the percentage of uranium was about 15 - 25 % at heating time of 40 - 50 minutes

  2. Herpes - resources

    Science.gov (United States)

    Genital herpes - resources; Resources - genital herpes ... following organizations are good resources for information on genital herpes : March of Dimes -- www.marchofdimes.org/complications/sexually- ...

  3. 1H, 15N and 13C assignments of domain 5 of Dictyostelium discoideum gelation factor (ABP-120) in its native and 8M urea-denatured states.

    Science.gov (United States)

    Hsu, Shang-Te Danny; Cabrita, Lisa D; Christodoulou, John; Dobson, Christopher M

    2009-06-01

    The gelation factor from Dictyostelium discoideum (ABP-120) is an actin binding protein consisting of six immunoglobulin (Ig) domains in the C-terminal rod domain. We have recently used the pair of domains 5 and 6 of ABP-120 as a model system for studying multi-domain nascent chain folding on the ribosome. Here we present the NMR assignments of domain 5 in its native and 8M urea-denatured states.

  4. Gelation of Photonic Microdomain Structures Formed in Semi-Dilute Solutions of Ultra-High-Molecular-Weight Polystyrene-b-Polybutadiene with Various Polybutadiene Contents

    International Nuclear Information System (INIS)

    Okamoto, S; Ito, S; Ando, K; Mouri, M; Ikeda, A; Hasegawa, H; Koshikawa, N

    2010-01-01

    Well-ordered microdomain structures were obtained in semi-dilute solutions and successfully stabilized by gelation. We used polystyrene-b-polybutadiene (PS-b-PB) diblock copolymer with the weight-averaged molecular weight varying from several hundred thousands to millions g/mol. The solutions had iridescent colors because the domain spacing is on the order of the wavelength of visible light. As the structures are susceptible to distortion by flow or vibration, structural fixation was carried out by gelation. The polybutadiene used has the microstructure of 1,2-linkage and hence the chains can be cross-linkable. The Small-Angle X-ray Scattering and the UV-vis spectroscopic measurements showed that in the case of PS-b-PBs with the PB volume fraction, φ PB , greater than about 50 vol % the microdomain structures were successfully fixed by gelation, while largely distorted in the case of those with φ PB < ca. 50 vol %. The SAXS scattering intensities were quantitatively analyzed by the scattering functions numerically calculated based on the one- and two-dimensional paracrystal theories and on the concentration fluctuation between the polymers and the solvent molecules.

  5. Slow-release Permanganate Gel (SRP-G) for Groundwater Remediation: Spreading, Gelation, and Release in Porous and Low-Permeability Media

    Science.gov (United States)

    Lee, E. S.; Hastings, J.; Kim, Y.

    2015-12-01

    Dense nonaqueous phase liquids (DNAPLs) like trichloroethylene (TCE) serve as the most common form of groundwater pollution in the world. Pore-plugging by the solid oxidation product MnO2 and limited lateral dispersion of the oxidant are two common problems with existing in-situ chemical oxidation (ISCO) schemes that could be alleviated through the development of a delayed gelation method for oxidant delivery. The objective of the current study was to further develop and optimize slow-release permanganate gel (SRP-G), a solution comprising colloidal silica and KMnO4, as a novel low-cost treatment option for large and dilute TCE plumes in groundwater. Batch tests showed that gelation could be delayed through manipulation of KMnO4 concentration, pH, and silica particle size of the SRP-G solution. In flow-through columns and flow-tanks filled with saturated sands, silica concentration had little effect on the gelation lag stage and release rate, but increasing silica concentration was associated with increasing release duration. When compared to a pure KMnO4 solution, visual observations and [MnO4-] measurements from flow tank tests demonstrated that the SRP-G prolonged the release duration and enhanced lateral spreading of the oxidant.

  6. The Use of Quality Benchmarking in Assessing Web Resources for the Dermatology Virtual Branch Library of the National electronic Library for Health (NeLH)

    OpenAIRE

    Boulos, MN Kamel; Roudsari, AV; Gordon, C; Gray, JA Muir

    2001-01-01

    Background In 1998, the U.K. National Health Service Information for Health Strategy proposed the implementation of a National electronic Library for Health to provide clinicians, healthcare managers and planners, patients and the public with easy, round the clock access to high quality, up-to-date electronic information on health and healthcare. The Virtual Branch Libraries are among the most important components of the National electronic Library for Health . They aim at creating online kno...

  7. An unprecedented amplification of near-infrared emission in a Bodipy derived π-system by stress or gelation.

    Science.gov (United States)

    Cherumukkil, Sandeep; Ghosh, Samrat; Praveen, Vakayil K; Ajayaghosh, Ayyappanpillai

    2017-08-01

    We report an unprecedented strategy to generate and amplify near-infrared (NIR) emission in an organic chromophore by mechanical stress or gelation pathways. A greenish-yellow emitting film of π-extended Bodipy-1 , obtained from n -decane, became orange-red upon mechanical shearing, with a 15-fold enhancement in NIR emission at 738 nm. Alternatively, a DMSO gel of Bodipy-1 exhibited a 7-fold enhancement in NIR emission at 748 nm with a change in emission color from yellow to orange-red upon drying. The reason for the amplified NIR emission in both cases is established from the difference in chromophore packing, by single crystal analysis of a model compound ( Bodipy-2 ), which also exhibited a near identical emission spectrum with red to NIR emission (742 nm). Comparison of the emission features and WAXS and FT-IR data of the sheared n -decane film and the DMSO xerogel with the single crystal data supports a head-to-tail slipped arrangement driven by the N-H···F-B bonding in the sheared or xerogel states, which facilitates strong exciton coupling and the resultant NIR emission.

  8. Effects of rare sugar d-allulose on heat-induced gelation of surimi prepared from marine fish.

    Science.gov (United States)

    Ogawa, Masahiro; Inoue, Masaki; Hayakawa, Shigeru; O'Charoen, Siwaporn; Ogawa, Makiko

    2017-11-01

    d-Allulose (Alu), the C3-epimer of d-fructose, is a non-caloric sweetener (0.39 kcal g -1 ) with a suppressive effect on postprandial blood glucose elevation. The aim of this study was to investigate the effects of Alu used as a sweetener and gel improver instead of sucrose on heat-induced gelation of surimi. The puncture test of a heat-induced surimi gel showed that with 50 g kg -1 Alu the gel had 15% and 6% higher gel strength than the corresponding gel with sucrose (Suc) and with sorbitol (Sor), respectively. In addition, Alu-gel had 26% and 25% higher water-holding capacity (WHC) than Suc- and Sor-gel. Heating of myofibrillar protein with Alu, unlike Suc and Sor, facilitated the formation of both disulfide and non-disulfide crosslinks that might be associated with the mechanical properties and WHC of Alu-gel. Alu improves the mechanical properties and WHC of the heat-induced surimi gel. Furthermore, Alu is low in calories compared with Suc (4.0 kcal g -1 ) and Sor (3.0 kcal g -1 ). Thus Alu will be an alternative of Suc or Sor for developing surimi-based products with health benefits. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  9. The Effect of Various Acids to the Gelation Process to the Silica Gel Characteristic Using Organic Silica

    Science.gov (United States)

    Rahman, NA; Widiyastuti, W.; Sigit, D.; Ajiza, M.; Sujana, W.

    2018-01-01

    Bagasse ash is solid waste of cane sugar industry which contain of silica more than 51%. Some previous study of silica gel from bagasse ash have been conducted often and been applied. This study concerns about the effect of various acid used in the process of gelation to the characteristic of silica gel produced. Then, this silica gel will be used as adsorbent. As that, the silica gel must fulfill the requirements of adsorbent, as have good pores characteristics, fit in mesoporous size so that adsorbent diffusion process is not disturbed. A fitted pores size of silica gel can be prepared by managing acid concentration used. The effect of acid, organic acid (tartaric acid) and inorganic acid (hydrochloric acid), is investigated in detail. The acid is added into sodium silicate solution in that the gel is formed, the pores structures can be investigated with BET, the crystal form is analyzed with XRD and the pore structure is analyzed visually with SEM. By managing the acid concentration added, it gets the effect of acid to the pore structure of silica gel. The bigger concentration is, the bigger the pore’s size of silica gel produced.

  10. A novel method for the production of core-shell microparticles by inverse gelation optimized with artificial intelligent tools.

    Science.gov (United States)

    Rodríguez-Dorado, Rosalia; Landín, Mariana; Altai, Ayça; Russo, Paola; Aquino, Rita P; Del Gaudio, Pasquale

    2018-03-01

    Numerous studies have been focused on hydrophobic compounds encapsulation as oils. In fact, oils can provide numerous health benefits as synergic ingredient combined with other hydrophobic active ingredients. However, stable microparticles for pharmaceutical purposes are difficult to achieve when commonly techniques are used. In this work, sunflower oil was encapsulated in calcium-alginate capsules by prilling technique in co-axial configuration. Core-shell beads were produced by inverse gelation directly at the nozzle using a w/o emulsion containing aqueous calcium chloride solution in sunflower oil pumped through the inner nozzle while an aqueous alginate solution, coming out from the annular nozzle, produced the beads shell. To optimize process parameters artificial intelligence tools were proposed to optimize the numerous prilling process variables. Homogeneous and spherical microcapsules with narrow size distribution and a thin alginate shell were obtained when the parameters as w/o constituents, polymer concentrations, flow rates and frequency of vibration were optimized by two commercial software, FormRules® and INForm®, which implement neurofuzzy logic and Artificial Neural Networks together with genetic algorithms, respectively. This technique constitutes an innovative approach for hydrophobic compounds microencapsulation. Copyright © 2018 Elsevier B.V. All rights reserved.

  11. Silica-gel structural characterization during the initial phases of gelation and drying; Caracterizacao estrutural de geis de silica durante as etapas iniciais de gelacao e secagem

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Max Passos

    1997-12-31

    For centuries, glasses and ceramics have been made via melting or solid state reactions at temperatures above 100 deg C. The sol-gel process offers new approaches to the synthesis of glasses and ceramics, combining control of composition and structure at the molecular level with the ability to shape materials in bulk, powder, fiber and thin-film forms. The growth of sol-gel technology research is due to the many unique features of that class of materials. Major applications include optical elements and integrated optical devices, ceramic filters, membranes, supercondutors, magnetic, catalytic and manostructured materials to antioxidant, anticorrosion coatings and composite and biomedical materials. In this work a variety of techniques like spectroscopy, Raman spectroscopy, ultraviolet-visible spectroscopy, light scattering nuclear magnetic resonance, X ray diffraction and nitrogen adsorption have been employed to investigate the initial phase of the sol-gel transition of gamma ray irradiated tetramethoxysilane (TMOS) solutions and non-irradiated TMOS solution and to get information about the structure of the silica gels obtained under different gelation conditions. Typically the tetramethoxysilane solutions were prepared using a molar ratio of TMOS to demineralized water of 1 to 16. Some experiments were made under catalysed conditions. The mixing was carried out at room temperature. The turbidity and light scattering experiments on the polycondensation of tetramethoxysilane show that exists no drastic difference in the gelling time of a gamma ray irradiated and a non-irradiated TMOS+H{sub 2}O (1+16 M) solution. In the absence of a catalyst, the gelling time for both reactions occurs in about 3.30 h. When HNO{sub 3} (o.03 M) was used, the gelling time observed was 3 days. Raman and ultraviolet-visible spectroscopy show no drastic difference during the initial phase at the sol-gel transition under ambient temperature/pressure and under gamma radiation. The gels

  12. Silica-gel structural characterization during the initial phases of gelation and drying; Caracterizacao estrutural de geis de silica durante as etapas iniciais de gelacao e secagem

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Max Passos

    1996-12-31

    For centuries, glasses and ceramics have been made via melting or solid state reactions at temperatures above 100 deg C. The sol-gel process offers new approaches to the synthesis of glasses and ceramics, combining control of composition and structure at the molecular level with the ability to shape materials in bulk, powder, fiber and thin-film forms. The growth of sol-gel technology research is due to the many unique features of that class of materials. Major applications include optical elements and integrated optical devices, ceramic filters, membranes, supercondutors, magnetic, catalytic and manostructured materials to antioxidant, anticorrosion coatings and composite and biomedical materials. In this work a variety of techniques like spectroscopy, Raman spectroscopy, ultraviolet-visible spectroscopy, light scattering nuclear magnetic resonance, X ray diffraction and nitrogen adsorption have been employed to investigate the initial phase of the sol-gel transition of gamma ray irradiated tetramethoxysilane (TMOS) solutions and non-irradiated TMOS solution and to get information about the structure of the silica gels obtained under different gelation conditions. Typically the tetramethoxysilane solutions were prepared using a molar ratio of TMOS to demineralized water of 1 to 16. Some experiments were made under catalysed conditions. The mixing was carried out at room temperature. The turbidity and light scattering experiments on the polycondensation of tetramethoxysilane show that exists no drastic difference in the gelling time of a gamma ray irradiated and a non-irradiated TMOS+H{sub 2}O (1+16 M) solution. In the absence of a catalyst, the gelling time for both reactions occurs in about 3.30 h. When HNO{sub 3} (o.03 M) was used, the gelling time observed was 3 days. Raman and ultraviolet-visible spectroscopy show no drastic difference during the initial phase at the sol-gel transition under ambient temperature/pressure and under gamma radiation. The gels

  13. Analysis on Current Situation and Countermeasure of Domestic Electronic Commerce Logistics in the Internet Age——Based on Resource Dependence Theory

    Directory of Open Access Journals (Sweden)

    Zhang Jiapeng

    2017-01-01

    Full Text Available This paper analyzes the status of electric business logistics in the current Internet era in China, and combines the SWOT analysis with AHP to do the empirical analysis, then puts forward the countermeasure that the electric business logistics resource should be shared based on the resource dependence theory. Through the empirical analysis, it is found that the disadvantages and opportunities of the logistics status are important in the Internet era.The resource sharing strategy based on the resource dependence theory is more scientific. The rational use of Internet technology in electric business logistics industry can achieve “sharing”. It is of great significance for its balanced development, intelligent development and optimization and development.

  14. Effect of uranyl nitrate and free acid concentration in feed solution of gelation on UO2 kernel quality

    International Nuclear Information System (INIS)

    Masduki, B.; Wardaya; Widarmoko, A.

    1996-01-01

    An investigation on the effect of uranium and free nitric acid concentration of uranyl nitrate as feed of gelation process on quality of UO 2 kernel was done.The investigation is to look for some concentration of uranyl nitrate solutions those are optimum as feed for preparation of gelled UO 3 . Uranyl nitrate solution of various concentration of uranium (450; 500; 550; 600; 650; 700 g/l) and free nitric acid of (0.9; 1.0; 1.1 N) was made into feed solutions by adding urea and HMTA with mole ratio of urea/uranium and HMTA/uranium 2.1 and 2.0. The feed solutions were changed into spherical gelled UO 3 by dropping was done to get the optimum concentrations of uranyl nitrate solutions. The gelled UO 3 was soaked and washed with 2.5% ammonia solution for 17 hours, dried at 70 o C, calcined at 350 o C for 3 hours then reduced at 850 o C for 3 hours. At every step of the steps process the colour and percentage of well product of gelled UO 3 were noticed. The density and O/U ratio of end product (UO 2 kernel) was determined, the percentage of well product of all steps process was also determined. The three factor were used to chose the optimum concentration of uranyl nitrate solution. From this investigation it was concluded that the optimum concentration of uranyl nitrate was 600 g/l uranium with free nitric acid 0,9 - 1,0 N, the percentage of well product was 97% density of 6.12 - 4.8 g/cc and O/U ratio of 2.15 - 2.06. (author)

  15. Structure, dynamics and folding of an immunoglobulin domain of the gelation factor (ABP-120) from Dictyostelium discoideum.

    Science.gov (United States)

    Hsu, Shang-Te Danny; Cabrita, Lisa D; Fucini, Paola; Dobson, Christopher M; Christodoulou, John

    2009-05-15

    We have carried out a detailed structural and dynamical characterisation of the isolated fifth repeat of the gelation factor (ABP-120) from Dictyostelium discoideum (ddFLN5) by NMR spectroscopy to provide a basis for studies of co-translational folding on the ribosome of this immunoglobulin-like domain. The isolated ddFLN5 can fold autonomously in solution into a structure that resembles very closely the crystal structure of the domain in a construct in which the adjacent sixth repeat (ddFLN6) is covalently linked to its C-terminus in tandem but deviates locally from a second crystal structure in which ddFLN5 is flanked by ddFLN4 and ddFLN6 at both N- and C-termini. Conformational fluctuations were observed via (15)N relaxation methods and are primarily localised in the interstrand loops that encompass the C-terminal hemisphere. These fluctuations are distinct in location from the region where line broadening is observed in ddFLN5 when attached to the ribosome as part of a nascent chain. This observation supports the conclusion that the broadening is associated with interactions with the ribosome surface [Hsu, S. T. D., Fucini, P., Cabrita, L. D., Launay, H., Dobson, C. M. & Christodoulou, J. (2007). Structure and dynamics of a ribosome-bound nascent chain by NMR spectroscopy. Proc. Natl. Acad. Sci. USA, 104, 16516-16521]. The unfolding of ddFLN5 induced by high concentrations of urea shows a low population of a folding intermediate, as inferred from an intensity-based analysis, a finding that differs from that of ddFLN5 as a ribosome-bound nascent chain. These results suggest that interesting differences in detail may exist between the structure of the domain in isolation and when linked to the ribosome and between protein folding in vitro and the folding of a nascent chain as it emerges from the ribosome.

  16. Examination of an aloe vera galacturonate polysaccharide capable of in situ gelation for the controlled release of protein therapeutics

    Science.gov (United States)

    McConaughy, Shawn David

    A therapeutic delivery platform has been investigated with the ultimate goal of designing a sustained protein release matrix utilizing an in-situ gelling, acidic polysaccharide derived from the Aloe vera plant. The Aloe vera polysaccharide (AvP) has been examined in order to determine how chemical composition, structure, molecular weight and solution behavior affect gelation and protein/peptide delivery. Correlations are drawn between structural characteristics and solution behavior in order to determine the impact of polymer conformation and solvation on gel formation under conditions designed to simulate nasal applications. Steady state and dynamic rheology, classic and dynamic light scattering, zeta potential, pulse field gradient nuclear magnetic resonance and fluorescence spectroscopy have been employed to gain insight into the effects of galacturonic acid content, degree of methylation, entanglement and ionic strength on both solution behavior and the hydrogel state which ultimately governs protein/peptide release. This dissertation is divided into two sections. In the first section, a series of Aloe vera polysaccharides (AvP), from the pectin family have been structurally characterized indicating high galacturonic acid (GalA) content, low degree of methylester substitution (DM), low numbers of rhamnose residues and high molecular weight with respect to pectins extracted from traditional sources. The behavior of AvP was examined utilizing dilute solution, low-shear rheological techniques for specific molecular weight samples at selected conditions of ionic strength. From these dilute aqueous solution studies, the Mark-Houwink-Sakurada (MHS) constants (K and alpha), persistence length (Lp) and inherent chain stiffness (B parameter) were determined, indicating an expanded random coil in aqueous salt solutions. The critical concentration for transition from dilute to concentrated solution, C e, was determined by measuring both the zero shear viscosity and

  17. How Students Learn: Ways of Thinking about "Good Learning" in HE. EDNER (Formative Evaluation of the Distributed National Electronic Resource) Project. Issues Paper.

    Science.gov (United States)

    Manchester Metropolitan Univ. (England).

    This issues paper, one of a series of eight, is intended to distill formative evaluation questions on topics that are central to the development of the higher and further education information environment in the United Kingdom. The topic of this first issues paper is a conceptual framework that can help members of a project (information resource)…

  18. 1,3:2,4-Dibenzylidene-D-sorbitol (DBS) and its derivatives--efficient, versatile and industrially-relevant low-molecular-weight gelators with over 100 years of history and a bright future.

    Science.gov (United States)

    Okesola, Babatunde O; Vieira, Vânia M P; Cornwell, Daniel J; Whitelaw, Nicole K; Smith, David K

    2015-06-28

    Dibenzylidene-D-sorbitol (DBS) has been a well-known low-molecular-weight gelator of organic solvents for over 100 years. As such, it constitutes a very early example of a supramolecular gel--a research field which has recently developed into one of intense interest. The ability of DBS to self-assemble into sample-spanning networks in numerous solvents is predicated upon its 'butterfly-like' structure, whereby the benzylidene groups constitute the 'wings' and the sorbitol backbone the 'body'--the two parts representing the molecular recognition motifs underpinning its gelation mechanism, with the nature of solvent playing a key role in controlling the precise assembly mode. This gelator has found widespread applications in areas as diverse as personal care products and polymer nucleation/clarification, and has considerable potential in applications such as dental composites, energy technology and liquid crystalline materials. Some derivatives of DBS have also been reported which offer the potential to expand the scope and range of applications of this family of gelators and endow the nansocale network with additional functionality. This review aims to explain current trends in DBS research, and provide insight into how by combining a long history of application, with modern methods of derivatisation and analysis, the future for this family of gelators is bright, with an increasing number of high-tech applications, from environmental remediation to tissue engineering, being within reach.

  19. 大學圖書館電子資源之需求分析與行銷策略之研究 A Study of Demands Analysis and Marketing Strategy of Electronic Resources in University Library

    Directory of Open Access Journals (Sweden)

    Huang-Yu Liu

    2008-03-01

    Full Text Available 電子資源的出現,使得知識載體有了新的突破,提高了使用者的便利性與即時性。對於圖書館而言,如何使電子資源的使用效益達到最高,必須思考一套有效的行銷策略。電子資源行銷概念應以讀者為導向,尊重讀者的資訊需求,並利用各種宣傳技巧,行銷電子資源,使圖書館能提供更完善的服務。本研究之目的旨在探討讀者的使用需求及電子資源的推廣策略,以獲致最有效益的行銷方式。研究對象以開南大學日間部四學院(商學院、運輸觀光學院、資訊學院、人文社會學院)學生為樣本,佐以缺口分析模型為分析架構,藉以找出個案中讀者/學生對於電子資源使用的真實需求,並進而歸納出提供服務的大學圖書館在其推廣或行銷服務上可有的因應策略。The emergence of electronic resources has made new breakthrough in knowledge carriers because of their ease of use, instant availability, and the characteristic of no time and space constraints. For public libraries to achieve maximum efficiency in its electronic resources, it is necessary to seek the most effective marketing strategies. Therefore, the marketing concept of the electronic resources should be reader oriented, such as respecting and understanding library user’s information needs. Libraries also need to utilize various media and techniques to market the electronic resources, so that more comprehensive services and experiences can be provided to readers. The purpose of this study is to investigate library user’s needs and promotion strategies of electronic resources in order to identify the most effective ways of marketing. This study focuses on the students of the four colleges (College of Business, College of Tourism, College of Information, and College of Humanities and Social Science in Kainan University as subjects in the survey questionnaire. It uses the Gap Analysis

  20. Influence of THFA on the surface area and porosity of U3O8 kernel of produced by external gelation process

    International Nuclear Information System (INIS)

    Susilowati, Sri Rinanti; Triyono; Nawangsih, Endang; Widiyati, Sri

    2013-01-01

    The research of the influence of THFA on the surface area and porosity of U 3 O 8 by kernel external gelation results has done. U 3 0 8 kernel made by external gelation process using uranyl nitrate solution with various concentration of THFA in sol solution. UN solution preparation by dissolving UO 3 powder into 7N HNO 3 at a temperature of 60 °C with a certain amount and volume, resulting in a solution of uranyl nitrate with high uranium concentrations but low acidity. Preparation of sol begins by dissolving 1.8 9 of polyvinyl alcohol in demineralized water at 70 °C, the volume varied tetrahydrofurfural alcohol, then added a solution of UN stirring constantly until homogeneous. Sol solution was then dripped in 7N ammonia in the medium gelation column. Gel ADU diaging in ammonia solution 7N for 30 minutes, then washed with ammonia 2.5% and n propanol. ADU gel diameter was measured using calipers. ADU silenced gel at room temperature 48 hours and then dried in an oven 100 °C at a rate of temperature rising 5°C/minutes. After drying, the gel ADU calcined at 600°C with an increase rate of 5°C/minutes for 2 hours. Kernel density U 3 O 8 then analyzed, surface area, mean pore radius and total pore volume. U 3 O 8 best kernel at 2.5% THFA concentration conditions, because it has a high density is 7.877 g/mL and extensive porosity and lower surface area is 5,180 % and 4,898 m 2 /g. (author)

  1. Application of electronic learning tools for training of specialists in the field of information technologies for enterprises of mineral resources sector

    Directory of Open Access Journals (Sweden)

    Е. В. Катунцов

    2017-08-01

    Full Text Available The article shows the advantages of using modern electronic learning tools in the training of specialists for the mineral and raw materials complex and considers the basic principles of organizing training using these tools. The experience of using electronic learning tools using foreign teaching materials and involving foreign professors is described. A special attention is given to the electronic learning environment of the Cisco Networking Academy – Cisco NetAcad. The experience of teaching at the Networking Academy of the Saint-Petersburg Mining University is described. Details are given to modern virtual environments for laboratory work, such as Cisco Packet Tracer, GNS3 and Emulated Virtual Environment. The experience of using electronic learning technologies at the University of Economics of Bratislava is considered. It actively cooperates with a number of universities of other countries, such as the University of International Business (Almaty, the Eurasian National University named after LN Gumilyov (Astana and the Institute of Social and Humanitarian Knowledge (Kazan.

  2. Thiol-Ene Photo-Click Collagen-PEG Hydrogels: Impact of Water-Soluble Photoinitiators on Cell Viability, Gelation Kinetics and Rheological Properties

    Directory of Open Access Journals (Sweden)

    Róisín Holmes

    2017-06-01

    Full Text Available Thiol-ene photo-click hydrogels were prepared via step-growth polymerisation using thiol-functionalised type-I collagen and 8-arm poly(ethylene glycol norbornene-terminated (PEG-NB, as a potential injectable regenerative device. Type-I collagen was thiol-functionalised by a ring opening reaction with 2-iminothiolane (2IT, whereby up to 80 Abs.% functionalisation and 90 RPN% triple helical preservation were recorded via 2,4,6-Trinitrobenzenesulfonic acid (TNBS colorimetric assay and circular dichroism (CD. Type, i.e., either 2-Hydroxy-1-[4-(2-hydroxyethoxy phenyl]-2-methyl-1-propanone (I2959 or lithium phenyl-2,4,6-trimethylbenzoylphosphinate (LAP, and concentration of photoinitiator were varied to ensure minimal photoinitiator-induced cytotoxicity and to enable thiol-ene network formation of collagen-PEG mixtures. The viability of G292 cells following 24 h culture in photoinitiator-supplemented media was largely affected by the photoinitiator concentration, with I2959-supplemented media observed to induce higher toxic response (0.1 → 0.5% (w/v I2959, cell survival: 62 → 2 Abs.% compared to LAP-supplemented media (cell survival: 86 → 8 Abs.%. In line with the in vitro study, selected photoinitiator concentrations were used to prepare thiol-ene photo-click hydrogels. Gelation kinetics proved to be largely affected by the specific photoinitiator, with LAP-containing thiol-ene mixtures leading to significantly reduced complete gelation time (τ: 187 s with respect to I2959-containing mixtures (τ: 1683 s. Other than the specific photoinitiator, the photoinitiator concentration was key to adjusting the hydrogel storage modulus (G’, whereby 15-fold G’ increase (232 → 3360 Pa was observed in samples prepared with 0.5% (w/v compared to 0.1% (w/v LAP. Further thiol-ene formulations with 0.5% (w/v LAP and varied content of PEG-NB were tested to prepare photo-click hydrogels with porous architecture, as well as tunable storage modulus (G

  3. An operational utility assessment [electronic resource]: measuring the effectiveness of the Joint Concept Technology Demonstration (JCTD), Joint Forces Protection Advance Security System (JFPASS)

    OpenAIRE

    McGovern, Mark; Mayor, Jeffrey D.; Symmes, Joseph

    2008-01-01

    MBA Professional Report Planning modern military operations requires an accurate intelligence assessment of potential threats, combined with a detailed assessment of the physical theater of operations. This information can then be combined with equipment and manpower resources to set up a logistically supportable operation that mitigates as much of the enemy threat as possible. Given such a daunting challenge, military planners often turn to intelligent software agents to support their...

  4. Positive Perceptions of Access to Online Library Resources Correlates with Quality and Quantity of Scholarly Publications among Finnish Academics. A Review of: Vakkari, Pertti. “Perceived Influence of the Use of Electronic Information Resources on Scholarly Work and Publication Productivity.” Journal of the American Society for Information Science and Technology 59.4 (Feb. 15, 2008: 602-12.

    Directory of Open Access Journals (Sweden)

    Scott Marsalis

    2008-12-01

    Full Text Available Objective – To investigate the relationship between academics’ use of library electronic resources and their opinions regarding how these resources have impacted their work, and to investigate the association between this perceived influence and publication productivity during the previous two years.Design – Two specific questions added to an annual online user-survey questionnaire; additional data mined from surveySetting – Twenty-two Finnish Universities served by FinELib, the Finnish Electronic Library.Subjects – Seven hundred and sixty seven academic staff and full-time doctoral students.Methods – A questionnaire was posted in April 2007 on FinELib’s homepage and advertised on each university library’s mainpage, and focused on respondents’ experience in the previous two years. Participants selected answers either from a list of category choices, or, when measuring perceptions, by rating agreement with statements along a four-point scale. Controlled variables measured were the respondents’ academic position, their discipline, membership in a research group, whether their literature use was discipline-specific or interdisciplinary, and their perception of the availability online of the relevant core literature. The independent variable measured was the scholars’ perception of the impact of the use of electronic library resources on their work. The dependent variable measured was the scholars’ self-reported publications in the two years preceding the survey.Main Results – Participants reported a positive impact on the efficiency of their work, most strongly in areas of ease of access, with lesser impacts in the range of materials available to them and the ease with which they can keep up-to-date in their field. To a lesser extent, the scholars perceived a positive impact on the quality of their work. Upon analysis, the study found that access to online library resources improved scholars’ work by the interconnected

  5. Power Electronics

    DEFF Research Database (Denmark)

    Iov, Florin; Ciobotaru, Mihai; Blaabjerg, Frede

    2008-01-01

    is to change the electrical power production sources from the conventional, fossil (and short term) based energy sources to renewable energy resources. The other is to use high efficient power electronics in power generation, power transmission/distribution and end-user application. This paper discuss the most...... emerging renewable energy sources, wind energy, which by means of power electronics are changing from being a minor energy source to be acting as an important power source in the energy system. Power electronics is the enabling technology and the presentation will cover the development in wind turbine...... technology from kW to MW, discuss which power electronic solutions are most feasible and used today....

  6. Detection of the pyrogen in the radiopharmaceuticals using Limulus test and inhibitory factors in the gelation reaction

    International Nuclear Information System (INIS)

    Murata, Hajime; Iio, Masahiro; Yamada, Hideo; Chiba, Kazuo; Kobayashi, Masayoshi.

    1975-01-01

    To examine the sensitivities of the Limulus test and the inhibitory factors in radiopharmaceuticals, the following procedures were employed. Twenty commonly used radiopharmaceuticals were examined by Limulus Lysate (Pre-gel). In order to detect the inhibitory factors, several doses of endotoxin (E. coli) were added to the radiopharmaceuticals before the Limulus test was made and the results were compared with control results using saline solution of endotoxin. When the pH of the reaction solution lay out of a suitable range (6.0-7.5), the pH was adjusted by Tris-HCl buffer before the reaction. The sensitivity of the Limulus test control using Pre-gel was positive at a concentration of 10 -3 μg/ml of endotoxin. The Limulus test was sensitive and without inhibitory reactions for sup(99m)TcO 4 -, sup(99m)Tc-albumin, sup(99m)Tc-MAA, sup(99m)Tc-Sn-colloid, 131 I-hippurate, Na 131 I, Na 2 51 CrO 4 , 67 Ga-citrate and 57 Co-bleomycin as they were supplied. 111 In-DTPA, sup(99m)Tc-phytate, sup(99m)Tc-pyrophosphate, sup(99m)Tc-DTPA, 131 I-PVP, 59 FeCl 3 , Na-phosphate ( 32 P), 198 Au-colloid and 75 Se-selenomethionine needed to have their pH adjusted to avoid inhibition. Benzyl alcohol in the radiopharmaceutical showed an inhibitory effect at a concentration greater than 1%. Commonly used 169 Yb-DTPA which was evaluated by this test had a sensitivity of 2.5 x 10 -3 μg/ml due to addition of a small amount of benzyl alcohol. 131 I-BSP showed intense inhibition in gelation reaction. Contaminations of endotoxin were detected in sup(99m)Tc-albumin, sup(99m)Tc-Sn-colloid, 131 I-hippurate, Na 131 I, Na 2 51 CrO 4 , 198 Au-colloid, 57 Co-bleomycin and 75 Se-selenomethionine. (auth.)

  7. Detection of the pyrogen in the radiopharmaceuticals using Limulus test and inhibitory factors in the gelation reaction

    Energy Technology Data Exchange (ETDEWEB)

    Murata, H; Iio, M; Yamada, H; Chiba, K [Tokyo Metropolitan Geriatric Medical Center (Japan); Kobayashi, M

    1975-08-01

    To examine the sensitivities of the Limulus test and the inhibitory factors in radiopharmaceuticals, the following procedures were employed. Twenty commonly used radiopharmaceuticals were examined by Limulus Lysate (Pre-gel). In order to detect the inhibitory factors, several doses of endotoxin (E. coli) were added to the radiopharmaceuticals before the Limulus test was made and the results were compared with control results using saline solution of endotoxin. When the pH of the reaction solution lay out of a suitable range (6.0-7.5), the pH was adjusted by Tris-HCl buffer before the reaction. The sensitivity of the Limulus test control using Pre-gel was positive at a concentration of 10/sup -3/ ..mu..g/ml of endotoxin. The Limulus test was sensitive and without inhibitory reactions for sup(99m)TcO/sub 4/-, sup(99m)Tc-albumin, sup(99m)Tc-MAA, sup(99m)Tc-Sn-colloid, /sup 131/I-hippurate, Na/sup 131/I, Na/sub 2//sup 51/CrO/sub 4/, /sup 67/Ga-citrate and /sup 57/Co-bleomycin as they were supplied. /sup 111/In-DTPA, sup(99m)Tc-phytate, sup(99m)Tc-pyrophosphate, sup(99m)Tc-DTPA, /sup 131/I-PVP, /sup 59/FeCl/sub 3/, Na-phosphate (/sup 32/P), /sup 198/Au-colloid and /sup 75/Se-selenomethionine needed to have their pH adjusted to avoid inhibition. Benzyl alcohol in the radiopharmaceutical showed an inhibitory effect at a concentration greater than 1%. Commonly used /sup 169/Yb-DTPA which was evaluated by this test had a sensitivity of 2.5 x 10/sup -3/ ..mu..g/ml due to addition of a small amount of benzyl alcohol. /sup 131/I-BSP showed intense inhibition in gelation reaction. Contaminations of endotoxin were detected in sup(99m)Tc-albumin, sup(99m)Tc-Sn-colloid, /sup 131/I-hippurate, Na/sup 131/I, Na/sub 2//sup 51/CrO/sub 4/, /sup 198/Au-colloid, /sup 57/Co-bleomycin and /sup 75/Se-selenomethionine.

  8. Diffusion of Acetic Acid Across Oil/Water Interface in Emulsification-Internal Gelation Process for Preparation of Alginate Gel Beads

    Institute of Scientific and Technical Information of China (English)

    LIU Xiu-dong; YU Wei-ting; LIN Jun-zhang; MA Xiao-jun; YUAN Quan

    2007-01-01

    Alginate has been widely used in cell microencapsulation and drug delivery systems in the form of gel beads or microcapsules. Although an alternative novel emulsification-internal gelation technology has been established and both the properties and the potential applications of the beads in drug delivery systems have been studied, the mechanism has not been well understood compared with the traditional droplet method( external gelation technology). On the basis of our previous knowledge that the novel technology is composed of complicatedly consecutive processes with multistep diffusion and re action, and the diffusion of acetic acid across oil/water interface being the prerequisite that determines the occurrence and rate for the reactions and the structures and properties of final produced gel beads, a special emphasis was placed on the diffusion process. With the aid of diffusion modeling and simple experimental design, the diffusion rate constant and diffusion coefficient of acetic acid across oil/water interface were determined to be in the orders of magnitude of 10-6 and 10-16, respectively. This knowledge will be of particular importance in understanding and interpreting the formation, structure of the gel beads and the relationship between the structure and properties and guiding the preparation and quality control of the gel beads.

  9. Insights into gelation kinetics and gel front migration in cation-induced polysaccharide hydrogels by viscoelastic and turbidity measurements: Effect of the nature of divalent cations.

    Science.gov (United States)

    Huynh, Uyen T D; Chambin, Odile; du Poset, Aline Maire; Assifaoui, Ali

    2018-06-15

    Polysaccharide-based hydrogels were prepared by the diffusion of various divalent cations (X 2+ ) into the polygalacturonate (polyGal) solution through a dialysis membrane. The diffusion of various divalent cations (Mg 2+ , Ca 2+ , Zn 2+ and Ba 2+ ) was investigated. The polyGal gel growth was studied as a function of the initial cation concentration by both viscoelastic and turbidity measurements. We have demonstrated for the first time that the determination of the spatiotemporal variation of turbidity during the gelation process allowed to study the gel front migration. For Ca-polyGal, Zn-polyGal and Ba-polyGal, the gel front migration was characterized by the presence of a peak at the sol/gel interface. This peak was not observed in the case of Mg-polyGal where the gel was not formed. The apparent diffusion coefficient of the gel front (D app ) which was calculated from the evolution of this peak increased when the initial cation concentration was increased. Moreover, we have suggested a gelation mechanism based on the presence of a threshold molar ratio R* (=[X 2+ ]/[Galacturonic unit]) in which some point-like crosslinks are precursors of the formation of dimers and multimers inducing the contraction of the gel and thus the formation of the gel front. Copyright © 2018 Elsevier Ltd. All rights reserved.

  10. Microspheres Prepared by Internal Gelation for Actinide Co-Conversion - Influence of Organic Precursors in Initial Solution on Structure during Thermal Treatment

    International Nuclear Information System (INIS)

    Benay, G.; Modolo, G.; Robisson, A.C.; Grandjean, S.

    2008-01-01

    The fabrication of fuels or targets for transmutation of minor actinides requires a dust-free process. Such a requirement can be fulfilled by sol-gel methods, which allow the production of microsphere precursors. Internal gelation, one of these methods, was studied at Cea Marcoule and FZ (Forschungszentrum Juelich Germany). A study of the parameters involved in internal gelation (essentially the quantity of organic additives urea and hexa-methylene-tetramine (HMTA) present in the initial solution) was performed. Afterwards, the effects of these parameters on the structural evolution of the microspheres during thermal treatment were studied. It was observed that the structure and density of the microspheres are heavily dependant of the quantity of organic precursors present in the initial solution. Urea in particular has been found to bring porosity to the material, in addition to its catalytic effect on HMTA decomposition. The elimination of these organic compounds is however a major issue which causes the formation of cracks on the microspheres if no optimization is performed. (authors)

  11. Oil encapsulation in core-shell alginate capsules by inverse gelation II: comparison between dripping techniques using W/O or O/W emulsions.

    Science.gov (United States)

    Martins, Evandro; Poncelet, Denis; Rodrigues, Ramila Cristiane; Renard, Denis

    2017-09-01

    In the first part of this article, it was described an innovative method of oil encapsulation from dripping-inverse gelation using water-in-oil (W/O) emulsions. It was noticed that the method of oil encapsulation was quite different depending on the emulsion type (W/O or oil-in-water (O/W)) used and that the emulsion structure (W/O or O/W) had a high impact on the dripping technique and the capsules characteristics. The objective of this article was to elucidate the differences between the dripping techniques using both emulsions and compare the capsule properties (mechanical resistance and release of actives). The oil encapsulation using O/W emulsions was easier to perform and did not require the use of emulsion destabilisers. However, capsules produced from W/O emulsions were more resistant to compression and showed the slower release of actives over time. The findings detailed here widened the knowledge of the inverse gelation and gave opportunities to develop new techniques of oil encapsulation.

  12. Merge of terminological resources

    DEFF Research Database (Denmark)

    Henriksen, Lina; Braasch, Anna

    2012-01-01

    In our globalized world, the amount of cross-national communication increases rapidly, which also calls for easy access to multi-lingual high quality terminological resources. Sharing of terminology resources is currently becoming common practice, and efficient strategies for integration...... – or merging – of terminology resources are strongly needed. This paper discusses prerequisites for successful merging with the focus on identification of candidate duplicates of a subject domain found in the resources to be merged, and it describes automatic merging strategies to be applied to such duplicates...... in electronic terminology resources. Further, some perspectives of manual, supplementary assessment methods supporting the automatic procedures are sketched. Our considerations are primarily based on experience gained in the IATE and EuroTermBank projects, as merging was a much discussed issue in both projects....

  13. Renewable energy resources

    DEFF Research Database (Denmark)

    Ellabban, Omar S.; Abu-Rub, Haitham A.; Blaabjerg, Frede

    2014-01-01

    Electric energy security is essential, yet the high cost and limited sources of fossil fuels, in addition to the need to reduce greenhouse gasses emission, have made renewable resources attractive in world energy-based economies. The potential for renewable energy resources is enormous because...... they can, in principle, exponentially exceed the world's energy demand; therefore, these types of resources will have a significant share in the future global energy portfolio, much of which is now concentrating on advancing their pool of renewable energy resources. Accordingly, this paper presents how...... renewable energy resources are currently being used, scientific developments to improve their use, their future prospects, and their deployment. Additionally, the paper represents the impact of power electronics and smart grid technologies that can enable the proportionate share of renewable energy...

  14. Caffeine as a Gelator

    Directory of Open Access Journals (Sweden)

    Nonappa

    2016-03-01

    Full Text Available Caffeine (a stimulant and ethanol (a depressant may have opposite effects in our body, but under in vitro conditions they can “gel” together. Caffeine, being one of the widely used stimulants, continued to surprise the scientific community with its unprecedented biological, medicinal and physicochemical properties. Here, we disclose the supramolecular self-assembly of anhydrous caffeine in a series of alcoholic and aromatic solvents, rendering a highly entangled microcrystalline network facilitating the encapsulation of the solvents as illustrated using direct imaging, microscopy analysis and NMR studies.

  15. EFFECTIVE ELECTRONIC TUTORIAL

    Directory of Open Access Journals (Sweden)

    Andrei A. Fedoseev

    2014-01-01

    Full Text Available The article analyzes effective electronic tutorials creation and application based on the theory of pedagogy. Herewith the issues of necessary electronic tutorial functional, ways of the educational process organization with the use of information and communication technologies and the logistics of electronic educational resources are touched upon. 

  16. Properties of bioadhesive ketoprofen liquid suppositories: preparation, determination of gelation temperature, viscosity studies and evaluation of mechanical properties using texture analyzer by 4 × 4 factorial design.

    Science.gov (United States)

    Ozgüney, Işık; Kardhiqi, Anita

    2014-12-01

    Development and evaluation of thermosensitive and bioadhesive liquid suppositories containing ketoprofen (KP). This study was conducted to develope thermosensitive and bioadhesive liquid suppositories containing KP using poloxamer and different bioadhesive polymers and to investigate their gelation temperature, viscosity and mechanical properties. Bioadhesive liquid suppositories were prepared by the cold method using poloxamer 407 (P 407), Poloxamer 188 (P 188) and various amounts of different bioadhesive polymers. Their gelation temperatures, viscosity values and mechanical properties were determined using texture analyzer by 4 × 4 factorial design. It was seen that in presence of KP, gelation temperature of formulation P 407/P 188 (4/20%) significantly decreased from 64 to 37.1 °C. It is to be noted that addition of increasing concentrations of bioadhesive polymers lowered gelation temperature and its decrease was highest with addition of Carbopol 934 P (C). Results of texture profile analysis (TPA) showed that formulations containing C have significantly higher hardness and adhesiveness values than other bioadhesive formulations. According to TPA, gel structure of liquid suppository formulation F5, containing P 407/P 188/KP/C (4/20/2.5/0.8%), exhibited the greatest hardness, compressibilty, adhesiveness and besides greatest viscosity. According to mechanical properties and viscosity values, it was concluded that F5 could be a promising formulation.

  17. Real-world health outcomes in adults with moderate-to-severe psoriasis in the United States: a population study using electronic health records to examine patient-perceived treatment effectiveness, medication use, and healthcare resource utilization.

    Science.gov (United States)

    Armstrong, April W; Foster, Shonda A; Comer, Brian S; Lin, Chen-Yen; Malatestinic, William; Burge, Russel; Goldblum, Orin

    2018-06-28

    Little is known regarding real-world health outcomes data among US psoriasis patients, but electronic health records (EHR) that collect structured data at point-of-care may provide opportunities to investigate real-world health outcomes among psoriasis patients. Our objective was to investigate patient-perceived treatment effectiveness, patterns of medication use (duration, switching, and/or discontinuation), healthcare resource utilization, and medication costs using real-world data from psoriasis patients. Data for adults (≥18-years) with a dermatology provider-given diagnosis of psoriasis from 9/2014-9/2015 were obtained from dermatology practices using a widely used US dermatology-specific EHR containing over 500,000 psoriasis patients. Disease severity was captured by static physician's global assessment and body surface area. Patient-perceived treatment effectiveness was assessed by a pre-defined question. Treatment switching and duration were documented. Reasons for discontinuations were assessed using pre-defined selections. Healthcare resource utilization was defined by visit frequency and complexity. From 82,621 patients with psoriasis during the study period, patient-perceived treatment effectiveness was investigated in 2200 patients. The proportion of patients reporting "strongly agree" when asked if their treatment was effective was highest for biologics (73%) and those reporting treatment adherence (55%). In 16,000 patients who received oral systemics and 21,087 patients who received biologics, median treatment duration was longer for those who received biologics (160 vs. 113 days, respectively). Treatment switching was less frequent among patients on systemic monotherapies compared to those on combination therapies. The most common reason for discontinuing biologics was loss of efficacy; the most common reason for discontinuing orals was side effects. In 28,754 patients, higher disease severity was associated with increased healthcare resource

  18. Water Resources

    International Nuclear Information System (INIS)

    Abira, M.A.

    1997-01-01

    Water is essential for life and ecological sustenance; its availability is essential component of national welfare and productivity.The country's socio-economic activities are largely dependent on the natural endowment of water resources. Kenya's water resources comprises of surface waters (rivers, lakes and wetlands) and ground water. Surface water forms 86% of total water resources while the rest is ground water Geological, topographical and climatic factors influence the natural availability and distribution of water with the rainfall distribution having the major influence. Water resources in Kenya are continuously under threat of depletion and quality degradation owing to rising population, industrialization, changing land use and settlement activities as well as natural changes. However, the anticipated climate change is likely to exacerbate the situation resulting in increased conflict over water use rights in particular, and, natural resource utilisation in general. The impacts of climate change on the water resources would lead to other impacts on environmental and socio-economic systems

  19. Monte Carlo simulation of non-linear free radical polymerization using a percolation kinetic gelation model (I): free radical homo polymerization

    International Nuclear Information System (INIS)

    Ghiass, M.; Dabir, B.; Nikazar, M.; Rey, A.D.; Mirzadeh, H.

    2001-01-01

    A kinetic gelation model that incorporates the kinetics of free radical homo polymerization is implemented to determine the effects of kinetics on polymerization statistics and microstructures. The simulation is performed on a simple cubic lattice that has 100 sites in each direction. A new algorithm for random selecting of the next step in a self-avoiding random walk and very efficient mechanisms of mobility of components are introduced to improve the generality of the predictions by removing commonly accruing deficiencies due to early trapping of radicals. A first order kinetics is considered for decomposition of initiator that enables us to consider the effect of temperature on polymerization reaction. Better understanding of microstructural evolution during polymerization and providing a framework to produce a realistic system of highly packed random chains within polymer network are among the benefits of model

  20. Effect of N-Ethylmaleimide as a Blocker of Disulfide Crosslinks Formation on the Alkali-Cold Gelation of Whey Proteins.

    Directory of Open Access Journals (Sweden)

    Zhao Lei

    Full Text Available N-ethylmaleimide (NEM was used to verify that no new disulfide crosslinks were formed during the fascinating rheology of the alkali cold-gelation of whey proteins, which show Sol-Gel-Sol transitions with time at pH > 11.5. These dynamic transitions involve the formation and subsequent destruction of non-covalent interactions between soluble whey aggregates. Therefore, incubation of aggregates with NEM was expected not to affect much the rheology. Experiments show that very little additions of NEM, such as 0.5 mol per mol of protein, delayed and significantly strengthened the metastable gels formed. Interactions between whey protein aggregates were surprisingly enhanced during incubation with NEM as inferred from oscillatory rheometry at different protein concentrations, dynamic swelling, Trp fluorescence and SDS-PAGE measurements.

  1. Effect of N-Ethylmaleimide as a Blocker of Disulfide Crosslinks Formation on the Alkali-Cold Gelation of Whey Proteins

    Science.gov (United States)

    Lei, Zhao; Chen, Xiao Dong

    2016-01-01

    N-ethylmaleimide (NEM) was used to verify that no new disulfide crosslinks were formed during the fascinating rheology of the alkali cold-gelation of whey proteins, which show Sol-Gel-Sol transitions with time at pH > 11.5. These dynamic transitions involve the formation and subsequent destruction of non-covalent interactions between soluble whey aggregates. Therefore, incubation of aggregates with NEM was expected not to affect much the rheology. Experiments show that very little additions of NEM, such as 0.5 mol per mol of protein, delayed and significantly strengthened the metastable gels formed. Interactions between whey protein aggregates were surprisingly enhanced during incubation with NEM as inferred from oscillatory rheometry at different protein concentrations, dynamic swelling, Trp fluorescence and SDS-PAGE measurements. PMID:27732644

  2. Addition of sodium caseinate to skim milk increases nonsedimentable casein and causes significant changes in rennet-induced gelation, heat stability, and ethanol stability.

    Science.gov (United States)

    Lin, Yingchen; Kelly, Alan L; O'Mahony, James A; Guinee, Timothy P

    2017-02-01

    The protein content of skim milk was increased from 3.3 to 4.1% (wt/wt) by the addition of a blend of skim milk powder and sodium caseinate (NaCas), in which the weight ratio of skim milk powder to NaCas was varied from 0.8:0.0 to 0.0:0.8. Addition of NaCas increased the levels of nonsedimentable casein (from ∼6 to 18% of total casein) and calcium (from ∼36 to 43% of total calcium) and reduced the turbidity of the fortified milk, to a degree depending on level of NaCas added. Rennet gelation was adversely affected by the addition of NaCas at 0.2% (wt/wt) and completely inhibited at NaCas ≥0.4% (wt/wt). Rennet-induced hydrolysis was not affected by added NaCas. The proportion of total casein that was nonsedimentable on centrifugation (3,000 × g, 1 h, 25°C) of the rennet-treated milk after incubation for 1 h at 31°C increased significantly on addition of NaCas at ≥0.4% (wt/wt). Heat stability in the pH range 6.7 to 7.2 and ethanol stability at pH 6.4 were enhanced by the addition of NaCas. It is suggested that the negative effect of NaCas on rennet gelation is due to the increase in nonsedimentable casein, which upon hydrolysis by chymosin forms into small nonsedimentable particles that physically come between, and impede the aggregation of, rennet-altered para-casein micelles, and thereby inhibit the development of a gel network. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.

  3. Development of new ionic gelation strategy: Towards the preparation of new monodisperse and stable hyaluronic acid/β-cyclodextrin-grafted chitosan nanoparticles as drug delivery carriers for doxorubicin

    Science.gov (United States)

    Mihoub, Amina Ben; Saidat, Boubakeur; Bal, Youssef; Frochot, Céline; Vanderesse, Régis; Acherar, Samir

    2018-03-01

    In the present study, β-cyclodextrin-grafted chitosan nanoparticles (β-CD- g-CS NPs) were prepared using a new ionic gelation strategy involving a synergistic effect of NaCl (150 mmol/L), 4-(2-hydroxyethyl)-1-piperazineethanesulfonic acid (HEPES, 10 mmol/L), and water bath sonication. This new strategy afforded smaller and more monodisperse β-CD- g-CS NPs vs. the classical ionic gelation method. New HA/β-CD- g-CS NPs were also prepared using the above-mentioned strategy by adding hyaluronic acid (HA) to the β-CD- g-CS copolymer at different weight ratios until the ZP values conversion. The best result was obtained with the weight ratio of w(HA): w(β-CD- g-CS) = 2:1 and furnished new spherical and smooth HA/β-CD- g-CS NPs. Furthermore, the stability of β- CD- g-CS NPs and HA/β-CD- g-CS NPs at 4°C in physiological medium (pH 7.4) was compared for 3 weeks period and showed that HA/β-CD- g-CS NPs were more stable all maintaining their monodispersity and high negative ZP values compared to β-CD- g-CS NPs. Finally, preliminary study of HA/β-CD- g-CS NPs as carrier for the controlled release of the anticancer drug doxorubicin was investigated. These new HA/β-CD- g-CS NPs can potentially be used as drug delivery and targeting systems for cancer treatment.

  4. Electronics and electronic systems

    CERN Document Server

    Olsen, George H

    1987-01-01

    Electronics and Electronic Systems explores the significant developments in the field of electronics and electronic devices. This book is organized into three parts encompassing 11 chapters that discuss the fundamental circuit theory and the principles of analog and digital electronics. This book deals first with the passive components of electronic systems, such as resistors, capacitors, and inductors. These topics are followed by a discussion on the analysis of electronic circuits, which involves three ways, namely, the actual circuit, graphical techniques, and rule of thumb. The remaining p

  5. Uranium resources

    International Nuclear Information System (INIS)

    Gangloff, A.

    1978-01-01

    It is first indicated how to evaluate the mining resources as a function of the cost of production and the degree of certainty in the knowledge of the deposit. A table is given of the world resources (at the beginning 1977) and resources and reserves are compared. There is a concordance between requirements and possible production until 1990. The case of France is examined: known reserves, present and future prospection, present production (In 1978 2200 T of U metal will be produced from 3 French processing plants), production coming from Cogema. A total production of 2000 T in 1980 and 10.000 in 1985 is expected [fr

  6. Seaweed resources

    Digital Repository Service at National Institute of Oceanography (India)

    Deshmukhe, G.V.; Dhargalkar, V.K.; Untawale, A.G.

    The chapter summarizes our present knowledge of the seaweed resources of the Indian Ocean region with regard to the phytogeographical distribution, composition, biomass, utilization, cultivation, conservation and management. The voluminous data...

  7. Arthritis - resources

    Science.gov (United States)

    Resources - arthritis ... The following organizations provide more information on arthritis : American Academy of Orthopaedic Surgeons -- orthoinfo.aaos.org/menus/arthritis.cfm Arthritis Foundation -- www.arthritis.org Centers for Disease Control and Prevention -- www. ...

  8. Mineral resources

    Digital Repository Service at National Institute of Oceanography (India)

    Valsangkar, A.B.

    (placers), biogenous (ooze, limestone) or chemogenous (phosphorites and polymetallic nodules) type. In recent years, hydrothermal deposits, cobalt crust and methane gas hydrates are considered as frontier resources. Their distribution depends upon proximity...

  9. Depression - resources

    Science.gov (United States)

    Resources - depression ... Depression is a medical condition. If you think you may be depressed, see a health care provider. ... following organizations are good sources of information on depression : American Psychological Association -- www.apa.org/topics/depression/ ...

  10. Hemophilia - resources

    Science.gov (United States)

    Resources - hemophilia ... The following organizations provide further information on hemophilia : Centers for Disease Control and Prevention -- www.cdc.gov/ncbddd/hemophilia/index.html National Heart, Lung, and Blood Institute -- www.nhlbi.nih.gov/ ...

  11. Diabetes - resources

    Science.gov (United States)

    Resources - diabetes ... The following sites provide further information on diabetes: American Diabetes Association -- www.diabetes.org Juvenile Diabetes Research Foundation International -- www.jdrf.org National Center for Chronic Disease Prevention and Health Promotion -- ...

  12. Forest Resources

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-06-01

    Forest biomass is an abundant biomass feedstock that complements the conventional forest use of wood for paper and wood materials. It may be utilized for bioenergy production, such as heat and electricity, as well as for biofuels and a variety of bioproducts, such as industrial chemicals, textiles, and other renewable materials. The resources within the 2016 Billion-Ton Report include primary forest resources, which are taken directly from timberland-only forests, removed from the land, and taken to the roadside.

  13. Teaching Resources

    Science.gov (United States)

    Physics?" Poster Pamphlets/Books/SPIN-UP Resources Making and Sustaining Changes in Undergraduate AAPT.org - American Association of Physics Teachers Skip to content Skip to navigation Skip to local navigation AAPT - American Association of Physics Teachers Go Sign In / Online Services Join

  14. Resource Mobilization

    International Development Research Centre (IDRC) Digital Library (Canada)

    constitute endorsement of the product and is given only for information. ..... point where they could significantly impact an organization's financial viability. This alternative ... putting in place internal systems and processes that enable the resource .... control over the incorporation of non-profit organizations. ..... Accounting.

  15. Resource Mobilization

    International Development Research Centre (IDRC) Digital Library (Canada)

    Annex 1: The Scoping Study on Donor Funding for. Development Research in ... publication of the Resource Mobilization: A Practical Guide for Research .... applied the concept or technique, which validates the practical application of ... some other staff member would write up a grant application addressed to one, two, or a ...

  16. Facile synthesis of radial-like macroporous superparamagnetic chitosan spheres with in-situ co-precipitation and gelation of ferro-gels.

    Directory of Open Access Journals (Sweden)

    Chih-Hui Yang

    Full Text Available Macroporous chitosan spheres encapsulating superparamagnetic iron oxide nanoparticles were synthesized by a facile and effective one-step fabrication process. Ferro-gels containing ferrous cations, ferric cations and chitosan were dropped into a sodium hydroxide solution through a syringe pump. In addition, a sodium hydroxide solution was employed for both gelation (chitosan and co-precipitation (ferrous cations and ferric cations of the ferro-gels. The results showed that the in-situ co-precipitation of ferro-ions gave rise to a radial morphology with non-spheroid macro pores (large cavities inside the chitosan spheres. The particle size of iron oxide can be adjusted from 2.5 nm to 5.4 nm by tuning the concentration of the sodium hydroxide solution. Using Fourier Transform Infrared Spectroscopy and X-ray diffraction spectra, the synthesized nanoparticles were illustrated as Fe(3O(4 nanoparticles. In addition, the prepared macroporous chitosan spheres presented a super-paramagnetic behaviour at room temperature with a saturation magnetization value as high as ca. 18 emu/g. The cytotoxicity was estimated using cell viability by incubating doses (0∼1000 µg/mL of the macroporous chitosan spheres. The result showed good viability (above 80% with alginate chitosan particles below 1000 µg/mL, indicating that macroporous chitosan spheres were potentially useful for biomedical applications in the future.

  17. Single-Handed Helical Polybissilsesquioxane Nanotubes and Mesoporous Nanofibers Prepared by an External Templating Approach Using Low-Molecular-Weight Gelators

    Directory of Open Access Journals (Sweden)

    Jing Hu

    2017-01-01

    Full Text Available Chiral low-molecular-weight gelators (LMWGs derived from amino acids can self-assemble into helical fibers and twisted/coiled nanoribbons by H-bonding and π–π interaction. Silica nanotubes with single-handed helices have been prepared using chiral LMWGs through sol–gel transcription. Molecular-scale chirality exists at the inner surfaces. Here, we discuss single-handed helical aromatic ring-bridged polybissilsesquioxane nanotubes and mesoporous nanofibers prepared using chiral LMWGs. This review aims at describing the formation mechanisms of the helical nanostructures, the origination of optical activity, and the applications for other helical nanomaterial preparation, mainly based on our group’s results. The morphology and handedness can be controlled by changing the chirality and kinds of LMWGs and tuning the reaction conditions. The aromatic rings arrange in a partially crystalline structure. The optical activity of the polybissilsesquioxane nanotubes and mesoporous nanofibers originates from chiral defects, including stacking and twisting of aromatic groups, on the inner surfaces. They can be used as the starting materials for preparation of silica, silicon, carbonaceous, silica/carbon, and silicon carbide nanotubes.

  18. Influence of adding Sea Spaghetti seaweed and replacing the animal fat with olive oil or a konjac gel on pork meat batter gelation. Potential protein/alginate association.

    Science.gov (United States)

    Fernández-Martín, F; López-López, I; Cofrades, S; Colmenero, F Jiménez

    2009-10-01

    Standard and modulated differential scanning calorimetry (DSC, MDSC) and dynamic rheological thermal analysis (DRTA) were used to in situ simulate the batter gelation process. Texture profile analysis (TPA) and conventional quality evaluations were applied to processed products. Sea Spaghetti seaweed addition was highly effective at reinforcing water/oil retention capacity, hardness and elastic modulus in all formulations. Olive oil substituting half pork fat yielded a presumably healthier product with slightly better characteristics than control. A konjac-starch mixed gel replacing 70% of pork fat produced a similar product to control but with nearly 10% more water. DSC revealed the currently unknown phenomenon that Sea Spaghetti alginates apparently prevented thermal denaturation of a considerable protein fraction. MDSC confirmed that this mainly concerned non-reversing effects, and displayed glass transition temperatures in the range of 55-65°C. DRTA and TPA indicated however much stronger alginate-type gels. It is tentatively postulated that salt-soluble proteins associate athermally with seaweed alginates on heating to constitute a separate phase in a thermal composite-gelling process.

  19. Control of Urania Crystallite Size by HMTA-Urea Reactions in the Internal Gelation Process for Preparing (U, Pu)O2Fuel Kernels

    Energy Technology Data Exchange (ETDEWEB)

    Collins, J.L.

    2005-04-26

    In the development of (U,Pu)O{sub 2} kernels by the internal gelation process for the Direct Press Spheroidized process at Oak Ridge National Laboratory, a novel crystal growth step was discovered that made it possible to prepare calcined porous kernels that could be used as direct-press feed for Fast Breeder Reactor pellet fabrication. High-quality pellets were prepared that were near theoretical density and that (upon examination) revealed no evidence of sphere remnants. The controlled crystal growth step involved using hexamethylenetetramine (HMTA)-urea stock solutions that were boiled for 60 min or less. Before this discovery, all the other crystal growth steps (when utilized) could reduce the tap density to only {approx}1.3 g/cm{sup 3}, which was not sufficiently low for use in ideal pellet pressing. The use of the boiled HMTA-urea solution allowed the tap density to be lowered to 0.93 g/cm{sup 3}, with the ideal density being about 1.0 g/cm{sup 3}. This report describes the development of this technology and its scaleup.

  20. Thermoreversible gelation polymer as an embolic material for aneurysm treatment: a delivery device for dermal fibroblasts and basic fibroblast growing factor into experimental aneurysms in rats.

    Science.gov (United States)

    Dobashi, Hisashi; Akasaki, Yasuharu; Yuki, Ichiro; Arai, Takao; Ohashi, Hiroki; Murayama, Yuichi; Takao, Hiroyuki; Abe, Toshiaki

    2013-11-01

    This study evaluates whether thermoreversible gelation polymer (TGP) can be used as a delivery device to deploy dermal fibroblasts and cytokines into experimental aneurysms in rats. The right common iliac artery of rats was surgically ligated and an experimental aneurysm was created by applying exogenous elastase. Seven days later, two aneurysms were harvested and used as controls (Group A), two were embolized with pure TGP (Group B), two were embolized with TGP and basic fibroblast growth factor (bFGF) (Group C) and two were embolized with TGP loaded with rat dermal fibroblasts (Group D). The aneurysms were also embolized with TGP mixed with dermal fibroblasts and bFGF at different concentrations (10 ng/ml: Group E (n=2), 100 ng/ml: Group F (n=2), 1000 ng/ml: Group G (n=2)). Each aneurysm sample was harvested after 7 days and histologic analyses were performed. The most advanced thrombus organization in the aneurysm, such as prominent fibroblast proliferation and collagen deposition, was observed in Groups E, F and G, although there was no noticeable difference between the groups. Moderate thrombus organization was seen in Group D and minimal thrombus organization was seen in Groups B and C. TGP mixed with both dermal fibroblasts and bFGF induced the most advanced thrombus organization in the experimental aneurysms followed by TGP mixed only with dermal fibroblasts. TGP may be useful as a delivery device to deploy fibroblasts and cytokines into aneurysms.

  1. Research of zirconia-based oxide spheres for CERMET fuel. Production through internal gelation process and the compatibility with Zr, Zircaloy-4 and Si

    International Nuclear Information System (INIS)

    Idemitsu, Kazuya; Inagaki, Yaohiro; Arima, Tatsumi

    2003-05-01

    Optimizing of sol-gel processes was carried out for manufacturing of ziroconium based oxide spheres used in CERMET fuels. In addition, compatibility of CERMET fuels was studied. The Zr 0.85-x Y 0.1 Er 0.05 Ce x O 2 (x=0.0-0.2) oxide spheres were made by preparation of suitable starting materials and the dropping method for an internal gelation process, and thorugh suitable drying, calcination and sintering processes. However, further studies were needed for optimizing the sintering condition. About the reaction of YSZ(yttria-stabilized zirconia) with Zr, Zry4 and Si, isothermal heating tests have been done at the temperature range from 800degC to 1150degC for a maximum of 112 days. Some reactions between YSZ and Zr were observed at temperatures ≥1000degC, which means the formation of a metallic reaction layer at the interface between them and the occurrence of meatallic phases inside the YSZ. Similar results were observed for the YSZ-Zry4 (cladding) system. The YSZ and Si were compatible below the temperature of 1000degC. However, above the temperatures, Si attacked YSZ so that the reaction layers formed on the YSZ side. (author)

  2. Two-Phase Diffusion Technique for the Preparation of Ultramacroporous/Mesoporous Silica Microspheres via Interface Hydrolysis, Diffusion, and Gelation of TEOS.

    Science.gov (United States)

    Ju, Minhua; Li, Yupeng; Yu, Liang; Wang, Chongqing; Zhang, Lixiong

    2018-02-06

    Honeycombed hierarchical ultramacroporous/mesoporous silica microspheres were prepared via the hydrolysis of TEOS in the oil-water interface, with subsequent diffusion and gelation in the acidic water-phase microdroplets with the assistance of a simple homemade microdevice. The diffusion of furfuryl alcohol (FA) also happened at a relatively high rate during the hydrolysis and diffusion of TEOS. Therefore, plenty of FA will be inside of the water microdroplets and form a decent number of polyfurfuryl alcohol (PFA) microparticles, thereby obtaining honeycombed hierarchical porosity silica microspheres with abundant ultramacroporous cavities and mesopores after calcination. It was found that the concentration of FA, residence time, and reaction temperature have significant effects on the porosity and pore size due to the influence on the diffusion rate and amount of FA in water-phase microdroplets. The honeycombed silica microspheres have obvious microscopic visible ultramacroporous cavities with the submicrometer cavity diameter as high as 85% porosity based on the rough overall volume of microsphere. N 2 adsorption-desorption isotherms show that the honeycombed hierarchical porosity silica microspheres have a high surface area of 602 m 2 g -1 , a mesopore volume of 0.77 cm 3 /g, and a mesopore porosity of 99.6% based on the total pore volume of N 2 adsorption-desorption. On the basis of the experiment results, a rational formation process of the honeycombed hierarchical porosity silica microspheres was deduced.

  3. Effect of extraction pH on heat-induced aggregation, gelation and microstructure of protein isolate from quinoa (Chenopodium quinoa Willd).

    Science.gov (United States)

    Ruiz, Geraldine Avila; Xiao, Wukai; van Boekel, Martinus; Minor, Marcel; Stieger, Markus

    2016-10-15

    The aim of this study was to determine the influence of extraction pH on heat-induced aggregation, gelation and microstructure of suspensions of protein isolates extracted from quinoa (Chenopodium quinoa Willd). Quinoa seed protein was extracted by alkaline treatment at various pH values (pH 8 (E8), 9 (E9), 10 (E10) and 11 (E11)), followed by acid precipitation. The obtained protein isolates were freeze dried. The protein isolates E8 and E9 resulted in a lower protein yield as well as less protein denaturation. These isolates also had a higher protein purity, more protein bands at higher molecular weights, and a higher protein solubility in the pH range of 3-4.5, compared to the isolates E10 and E11. Heating the 10%w/w protein isolate suspensions E8 and E9 led to increased aggregation, and semi-solid gels with a dense microstructure were formed. The isolate suspensions E10 and E11, on the other hand, aggregated less, did not form self-supporting gels and had loose particle arrangements. We conclude that extraction pH plays an important role in determining the functionality of quinoa protein isolates. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Chemical dependence - resources

    Science.gov (United States)

    Substance use - resources, Drug abuse - resources; Resources - chemical dependence ... are a good resource for information on drug dependence: National Council on Alcoholism and Drug Dependence -- ncadd. ...

  5. Algae Resources

    Energy Technology Data Exchange (ETDEWEB)

    None

    2016-06-01

    Algae are highly efficient at producing biomass, and they can be found all over the planet. Many use sunlight and nutrients to create biomass, which contain key components—including lipids, proteins, and carbohydrates— that can be converted and upgraded to a variety of biofuels and products. A functional algal biofuels production system requires resources such as suitable land and climate, sustainable management of water resources, a supplemental carbon dioxide (CO2) supply, and other nutrients (e.g., nitrogen and phosphorus). Algae can be an attractive feedstock for many locations in the United States because their diversity allows for highpotential biomass yields in a variety of climates and environments. Depending on the strain, algae can grow by using fresh, saline, or brackish water from surface water sources, groundwater, or seawater. Additionally, they can grow in water from second-use sources such as treated industrial wastewater; municipal, agricultural, or aquaculture wastewater; or produced water generated from oil and gas drilling operations.

  6. Uranium resources

    International Nuclear Information System (INIS)

    1976-01-01

    This is a press release issued by the OECD on 9th March 1976. It is stated that the steep increases in demand for uranium foreseen in and beyond the 1980's, with doubling times of the order of six to seven years, will inevitably create formidable problems for the industry. Further substantial efforts will be needed in prospecting for new uranium reserves. Information is given in tabular or graphical form on the following: reasonably assured resources, country by country; uranium production capacities, country by country; world nuclear power growth; world annual uranium requirements; world annual separative requirements; world annual light water reactor fuel reprocessing requirements; distribution of reactor types (LWR, SGHWR, AGR, HWR, HJR, GG, FBR); and world fuel cycle capital requirements. The information is based on the latest report on Uranium Resources Production and Demand, jointly issued by the OECD's Nuclear Energy Agency (NEA) and the International Atomic Energy Agency. (U.K.)

  7. Water resources

    International Nuclear Information System (INIS)

    2002-01-01

    The report entitled Climate Change Impacts and Adaptation : A Canadian Perspective, presents a summary of research regarding the impacts of climate change on key sectors over the past five years as it relates to Canada. This chapter on water resources describes how climate change will affect the supply of water in Canada. Water is one of Canada's greatest resources, which contributes about $7.5 to 23 billion per year to the Canadian economy. The decisions taken to adapt to climate change within the water resources sector will have profound implications in many other areas such as agriculture, human health, transportation and industry. The water related problems include water quality issues that relate to water shortages from droughts, or excesses from floods. The Intergovernmental Panel on Climate Change forecasts an increase in global average surface air temperatures of 1.4 to 5.8 degrees C by 2100. Such a change would impact the hydrological cycle, affecting runoff, evaporation patterns, and the amount of water stored in glaciers, lakes, wetlands and groundwater. The uncertainty as to the magnitude of these changes is due to the difficulty that climate models have in projecting future changes in regional precipitation patterns and extreme events. This chapter presents potential impacts of climate change on water resources in the Yukon, British Columbia, the Prairies, the Great Lakes basin, the Atlantic provinces, and the Arctic and Subarctic. The associated concerns for each region were highlighted. Adaptation research has focused on the impacts of supply and demand, and on options to adapt to these impacts. 60 refs., 2 tabs., 1 fig

  8. Resource Abundance and Resource Dependence in China

    NARCIS (Netherlands)

    Ji, K.; Magnus, J.R.; Wang, W.

    2010-01-01

    This paper reconsiders the ‘curse of resources’ hypothesis for the case of China, and distinguishes between resource abundance, resource rents, and resource dependence. Resource abundance and resource rents are shown to be approximately equivalent, and their association with resource dependence

  9. Internet and Electronic Information Management

    Science.gov (United States)

    2004-12-01

    centers to form consortia and share electronic information sources. Although traditional resource sharing arrangements encouraged competition rather...outside world, through public relations and through marketing information products or services, to its own competitive advantage (Davenport 1997: 193-217... electronic information sources are a challenge for electronic information managers. Libraries and information centers are no longer “the only game in town

  10. Automotive electronics design fundamentals

    CERN Document Server

    Zaman, Najamuz

    2015-01-01

    This book explains the topology behind automotive electronics architectures and examines how they can be profoundly augmented with embedded controllers. These controllers serve as the core building blocks of today’s vehicle electronics. Rather than simply teaching electrical basics, this unique resource focuses on the fundamental concepts of vehicle electronics architecture, and details the wide variety of Electronic Control Modules (ECMs) that enable the increasingly sophisticated "bells & whistles" of modern designs.  A must-have for automotive design engineers, technicians working in automotive electronics repair centers and students taking automotive electronics courses, this guide bridges the gap between academic instruction and industry practice with clear, concise advice on how to design and optimize automotive electronics with embedded controllers.

  11. Effect of Bovine Plasma Protein on Autolysis and Gelation of Protein Extracted from Giant Squid (Dosidicus gigas Mantle

    Directory of Open Access Journals (Sweden)

    Laura Raquel Marquez-Alvarez

    2015-01-01

    Full Text Available The effect of bovine plasma protein (BPP on the inhibition of autolytic activity and its effect on the gelling properties of a protein concentrate (PC obtained from jumbo squid (Dosidicus gigas mantle were investigated. Sols and gels were prepared from the PC by adding different amounts of BPP (0, 1, and 2%. Dynamic oscillatory measurements indicated that systems with 1% BPP had a higher elastic modulus (G′, in which hydrophobic interactions were favored. Concerning the technological and textural quality of the gels, BPP caused a greater water holding capacity (WHC, force, cohesiveness, and elasticity, probably due to improvement of the electrostatic and hydrophobic interactions during gel formation. Scanning electron microscopy (SEM allowed visualization of the formation of more rigid and ordered gels with less porosity when BPP was added. Therefore, the addition of BPP improved the gelling capacity of proteins extracted from giant squid.

  12. Uranium resource processing. Secondary resources

    International Nuclear Information System (INIS)

    Gupta, C.K.; Singh, H.

    2003-01-01

    This book concentrates on the processing of secondary sources for recovering uranium, a field which has gained in importance in recent years as it is environmental-friendly and economically in tune with the philosophy of sustainable development. Special mention is made of rock phosphate, copper and gold tailings, uranium scrap materials (both natural and enriched) and sea water. This volume includes related area of ore mineralogy, resource classification, processing principles involved in solubilization followed by separation and safety aspects

  13. Energy resources

    CERN Document Server

    Simon, Andrew L

    1975-01-01

    Energy Resources mainly focuses on energy, including its definition, historical perspective, sources, utilization, and conservation. This text first explains what energy is and what its uses are. This book then explains coal, oil, and natural gas, which are some of the common energy sources used by various industries. Other energy sources such as wind, solar, geothermal, water, and nuclear energy sources are also tackled. This text also looks into fusion energy and techniques of energy conversion. This book concludes by explaining the energy allocation and utilization crisis. This publ

  14. Electronic technology

    International Nuclear Information System (INIS)

    Kim, Jin Su

    2010-07-01

    This book is composed of five chapters, which introduces electronic technology about understanding of electronic, electronic component, radio, electronic application, communication technology, semiconductor on its basic, free electron and hole, intrinsic semiconductor and semiconductor element, Diode such as PN junction diode, characteristic of junction diode, rectifier circuit and smoothing circuit, transistor on structure of transistor, characteristic of transistor and common emitter circuit, electronic application about electronic equipment, communication technology and education, robot technology and high electronic technology.

  15. Mineral resources

    International Nuclear Information System (INIS)

    1991-09-01

    This paper reports that to prevent the concentration of control over federal oil and gas resources in a few companies or individuals, Congress has limited the number of acres of oil and gas leases that one party may control in a single state. An exception to this limitation involves lease acreage within the boundaries of development contracts. These contracts permit oil and gas lease operators and pipeline companies to contract with enough lessees to economically justify large-scale drilling operations for the production and transportation of oil and gas, subject to approval by the Secretary of the Interior, who must find that such contracts are in the public interest. Since 1986 Interior has entered into or approved 10 contracts with 12 lease operators for exploration of largely unleased federal lands-ranging from about 180,000 to 3.5 million acres in four western states-and has designated them as developmental contracts. GAO believes that the 10 contracts do not satisfy the legal requirements for development contracts because they are for oil and gas exploration on largely unleased federal lands, rather than for developing existing leases. By designating the 10 contracts as development contracts, Interior has enabled nine of the 12 contract parties to accumulate lease acreage that vastly exceeds the statutory acreage limitation. All nine of the contract parties were major or large independent oil companies. As a result, other parties who wish to participate in developing federal oil and gas resources within the four states may be adversely affected because the parties to Interior's contracts have been able to compete for and obtain lease acreage beyond the statutory acreage limitation. Although Interior believes that the Secretary has the discretion under law to use development contracts in the current manner, in April 1989 it ceased issuing these contracts pending completion of GAO's review

  16. The Electron

    Energy Technology Data Exchange (ETDEWEB)

    Thomson, George

    1972-01-01

    Electrons are elementary particles of atoms that revolve around and outside the nucleus and have a negative charge. This booklet discusses how electrons relate to electricity, some applications of electrons, electrons as waves, electrons in atoms and solids, the electron microscope, among other things.

  17. Hard electronics; Hard electronics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    Hard material technologies were surveyed to establish the hard electronic technology which offers superior characteristics under hard operational or environmental conditions as compared with conventional Si devices. The following technologies were separately surveyed: (1) The device and integration technologies of wide gap hard semiconductors such as SiC, diamond and nitride, (2) The technology of hard semiconductor devices for vacuum micro- electronics technology, and (3) The technology of hard new material devices for oxides. The formation technology of oxide thin films made remarkable progress after discovery of oxide superconductor materials, resulting in development of an atomic layer growth method and mist deposition method. This leading research is expected to solve such issues difficult to be easily realized by current Si technology as high-power, high-frequency and low-loss devices in power electronics, high temperature-proof and radiation-proof devices in ultimate electronics, and high-speed and dense- integrated devices in information electronics. 432 refs., 136 figs., 15 tabs.

  18. Social Studies Online Resources. Media Corner.

    Science.gov (United States)

    Wilson, Jeri, Ed.

    1995-01-01

    Maintains that three types of social studies activities are found on the information highway: (1) electronic mail; (2) information; and (3) conferencing. Describes examples of each. Discusses commercial services and resource materials and provides references to online services. (CFR)

  19. The Biomedical Resource Ontology (BRO) to enable resource discovery in clinical and translational research.

    Science.gov (United States)

    Tenenbaum, Jessica D; Whetzel, Patricia L; Anderson, Kent; Borromeo, Charles D; Dinov, Ivo D; Gabriel, Davera; Kirschner, Beth; Mirel, Barbara; Morris, Tim; Noy, Natasha; Nyulas, Csongor; Rubenson, David; Saxman, Paul R; Singh, Harpreet; Whelan, Nancy; Wright, Zach; Athey, Brian D; Becich, Michael J; Ginsburg, Geoffrey S; Musen, Mark A; Smith, Kevin A; Tarantal, Alice F; Rubin, Daniel L; Lyster, Peter

    2011-02-01

    The biomedical research community relies on a diverse set of resources, both within their own institutions and at other research centers. In addition, an increasing number of shared electronic resources have been developed. Without effective means to locate and query these resources, it is challenging, if not impossible, for investigators to be aware of the myriad resources available, or to effectively perform resource discovery when the need arises. In this paper, we describe the development and use of the Biomedical Resource Ontology (BRO) to enable semantic annotation and discovery of biomedical resources. We also describe the Resource Discovery System (RDS) which is a federated, inter-institutional pilot project that uses the BRO to facilitate resource discovery on the Internet. Through the RDS framework and its associated Biositemaps infrastructure, the BRO facilitates semantic search and discovery of biomedical resources, breaking down barriers and streamlining scientific research that will improve human health. Copyright © 2010 Elsevier Inc. All rights reserved.

  20. Electron radiography

    Science.gov (United States)

    Merrill, Frank E.; Morris, Christopher

    2005-05-17

    A system capable of performing radiography using a beam of electrons. Diffuser means receive a beam of electrons and diffuse the electrons before they enter first matching quadrupoles where the diffused electrons are focused prior to the diffused electrons entering an object. First imaging quadrupoles receive the focused diffused electrons after the focused diffused electrons have been scattered by the object for focusing the scattered electrons. Collimator means receive the scattered electrons and remove scattered electrons that have scattered to large angles. Second imaging quadrupoles receive the collimated scattered electrons and refocus the collimated scattered electrons and map the focused collimated scattered electrons to transverse locations on an image plane representative of the electrons' positions in the object.

  1. Information resources

    Science.gov (United States)

    Friend, Milton; Franson, J. Christian; Friend, Milton; Gibbs, Samantha E.J.; Wild, Margaret A.

    2015-10-19

    During recent decades, natural resources agency personnel and others involved with the management and stewardship of wildlife have experienced an increasing need to access information and obtain technical assistance for addressing a diverse array of wildlife disease issues. This Chapter provides a broad overview of selected sources for obtaining supplemental information and technical assistance for addressing wildlife disease issues in North America. Specifically, examples of existing major wildlife disease programs focusing on free-ranging wildlife populations are highlighted; training opportunities for enhancing within-agency wildlife disease response are identified; a selected reading list of wildlife disease references is provided; and selected Web sites providing timely information on wildlife disease are highlighted. No attempt is made to detail all the North American programs and capabilities that address disease in free-ranging wildlife populations. Instead, this Chapter is focused on enhancing awareness of the types of capabilities that exist as potential sources for assistance and collaboration between wildlife conservation agency personnel and others in addressing wildlife disease issues.

  2. GENDER ANALYSIS OF ELECTRONIC INFORMATION

    African Journals Online (AJOL)

    use of internet Search engines such as google, yahoo and other free internet resources was found ... empirical studies are undertaken to examine the influence of gender ... H3: Perceived ease of use is positively related to the use of electronic.

  3. Preparation of various hydrogels based on poly (Vinyl pyrrolidone) and poly ethylene glycol using gamma and electron irradiation

    International Nuclear Information System (INIS)

    Ajji, Z.

    2006-11-01

    Different hydrogels have been prepared using gamma and electron irradiation; the hydrogels are composed of poly(vinyl pyrolidone) (PVP), poly(ethylene glycol) (PEG). The influence of some process parameters on the properties of the hydrogels has been investigated as: the gel fraction, maximum swelling, swelling kinetics, and mechanical properties. In the first part of this study, hydrogel dressings have been prepared using electron irradiation, and the dressings are composed of poly(vinyl pyrrolidone) (PVP), poly(ethylene glycol) (PEG) and agar. The gel fraction increases with increasing PVP concentration due to increased crosslink density, and decreases with increasing the PEG concentration. PEG seems to act not only as plasticizer but also to modify the gel properties as gelation% and maximum swelling. The prepared hydrogels dressings could be considered as a good barrier against microbes. In the second part, different hydrogels have been prepared based on different concentrations of poly(vinyl pyrrolidone) and using gamma irradiation. The gel fraction and maximum swelling of the hydrogels has been determined. In the third part of the study, different hydrogels have been prepared based on different concentrations of poly(vinyl pyrrolidone) and poly(ethylene glycol) (PEG) with various molecular weights, and using gamma irradiation. The gel fraction and maximum swelling of the hydrogels has been determined. The data show that PEG with low molecular weight needs a high dose for the gelation, and the presence of PVP lowers the needed gelation dose. The maximum swelling decreases with increasing irradiation dose and the PVP concentration, which is due to higher crosslinks between the polymer chains. (author)

  4. Oscillator clustering in a resource distribution chain

    DEFF Research Database (Denmark)

    Postnov, D.; Sosnovtseva, Olga; Mosekilde, Erik

    2005-01-01

    separate the inherent dynamics of the individual oscillator from the properties of the coupling network. Illustrated by examples from microbiological population dynamics, renal physiology, and electronic oscillator theory, we show how competition for primary resources in a resource distribution chain leads...

  5. Shaping the Electronic Library--The UW-Madison Approach.

    Science.gov (United States)

    Dean, Charles W., Ed.; Frazier, Ken; Pope, Nolan F.; Gorman, Peter C.; Dentinger, Sue; Boston, Jeanne; Phillips, Hugh; Daggett, Steven C.; Lundquist, Mitch; McClung, Mark; Riley, Curran; Allan, Craig; Waugh, David

    1998-01-01

    This special theme section describes the University of Wisconsin-Madison's experience building its Electronic Library. Highlights include integrating resources and services; the administrative framework; the public electronic library, including electronic publishing capability and access to World Wide Web-based and other electronic resources;…

  6. Electrons, Electronic Publishing, and Electronic Display.

    Science.gov (United States)

    Brownrigg, Edwin B.; Lynch, Clifford A.

    1985-01-01

    Provides a perspective on electronic publishing by distinguishing between "Newtonian" publishing and "quantum-mechanical" publishing. Highlights include media and publishing, works delivered through electronic media, electronic publishing and the printed word, management of intellectual property, and recent copyright-law issues…

  7. 研究/電子資源使用統計標準與規範之探討/陳雪華;許嘉珍;朱雅琦 | Study of the Electronic Resources Usage Statistics Standards and Guidelines/ Hsueh-Hua Chen;Chia-Chen Hsu;Ya-Chi Chu

    Directory of Open Access Journals (Sweden)

    陳雪華、許嘉珍、朱雅琦

    2007-04-01

    Full Text Available

    近年來,由於資訊科技的進步,圖書館中的電子資源數量快速增加,所佔預算金額比例也大幅增長。圖書館希望能夠透過評鑑電子資源的使用,以便能夠在電 子資源館藏發展等方面做出正確的決策。由於體認到電子資源使用統計之重要性,圖書館界與相關組織紛紛發展或修訂圖書館統計標準,增列電子資源使用統計的項 目以充分反映圖書館電子資源使用之狀況。本文主要採用文獻分析法以及內容分析法,收集探討並比較近軍來國內外電子資源使用統計之相關規範及標準,包含 ISO 2789、 ICOLC Guidelines、州ANSI/NISO Z39.7、CNS13151、ARL E-Metrlcs、E-Measures Project、以及Project COUNTER等。

    Recently, due to the advances of information technology, electronic resources are gradually replacing print resources as the largest consumer of library acquisition budgets. Logically, libraries want to evaluate the usage of electronic resources and incorporate the results into their decision making regarding electronic resource acquisition. Over these years, there is a general awareness among libraries to develop statistics standards and guidelines for library electronic resources usage. In this paper, literature review and content analysis methods are used to compare several library statistics standards, including: ISO 2789 、ICOLC Guidelines、ANSI/NISO Z39.7、CNS13151、ARL E-Metrics、E-Measures Project、and Project COUNTER etc.

    頁次:89-102

  8. Hydrogel wound dressing preparation at the laboratory scale by using electron beam and gamma radiation

    International Nuclear Information System (INIS)

    Rapado Raneque, Manuel; Rodriguez Rodriguez, Alejandro; Peniche Covas, Carlos

    2013-01-01

    The present work describes the preparation of hydrogel based on cross-linked networks of poly (N-vinylpirrolidone), PVP, with polyethyleneglicol and agar with 90% water and PVP nancomposites with a synthetic nanoclay, Laponite XLG, for use as burn dressings. These systems were obtained in two ways: using gamma Co-60 and electron beam radiation. The gelation obtained dose was D g = 1.72 kGy. The elastic modulus of hydrogel was independent of the method of irradiation. It was 0.39 MPa for the hydrogel irradiated with gamma Co-60 and 0.38 MPa for electron beam irradiation. The elastic modulus of the nanocomposite membrane was 1.25 MPa, three times higher. These results indicate that the PVP/Laponite XLG nanocomposite hydrogel membrane is the best choice for wound dressing applications due to its high water sorption capacity and its superior mechanical properties.

  9. Electron detector

    International Nuclear Information System (INIS)

    Hashimoto, H.; Mogami, A.

    1975-01-01

    A device for measuring electron densities at a given energy level in an electron beam or the like having strong background noise, for example, in the detection of Auger electric energy spectrums is described. An electron analyzer passes electrons at the given energy level and at the same time electrons of at least one adjacent energy level. Detecting means associated therewith produce signals indicative of the densities of the electrons at each energy level and combine these signals to produce a signal indicative of the density of the electrons of the given energy level absent background noise

  10. World resources: engineering solutions

    Energy Technology Data Exchange (ETDEWEB)

    1976-01-01

    The proceedings include 10 papers that contribute to population environment; fossil fuel resources and energy conservation; nuclear and solar power; production of ores and manufacture and use of metallic resources; resources of manufactured and natural nonmetallic materials; water as a reusable resource; and timber as a replaceable resource.

  11. Electron/electron acoustic instability

    International Nuclear Information System (INIS)

    Gary, S.P.

    1987-01-01

    The electron acoustic wave becomes a normal mode of an unmagnetized collisionless plasma in the presence of two electron components with similar densities, but strongly disparate temperatures. The characteristic frequency of this mode is the plasma frequency of the cooler electron component. If these two electron components have a relative drift speed several times the thermal speed of the cooler component, the electron/electron acoustic instability may arise. This paper describes the parametric dependences of the threshold drift speed and maximum growth rate of this instability, and compares these with the same properties of the electron/ion acoustic instability. Under the condition of zero current, the electron/ion acoustic instability typically has the lower threshold drift speed, so that observation of the electron/electron acoustic instability is a strong indication of the presence of an electrical current in the plasma

  12. Precipitation and ultimate pH effect on chemical and gelation properties of protein prepared by isoelectric solubilization/precipitation process from pale, soft, exudative (PSE)-like chicken breast meat1.

    Science.gov (United States)

    Zhao, X; Xing, T; Chen, X; Han, M-Y; Li, X; Xu, X-L; Zhou, G-H

    2017-05-01

    Pale, soft, exudative (PSE)-like chicken breast is considered deteriorated raw material in the poultry meat industry that has inferior processing ability. The chemical and gelation properties of PSE-like chicken breast meat paste were studied. These pastes were prepared by the pH adjustment method and protein isolation using the isoelectric solubilization/precipitation (ISP) process from PSE-like chicken meat. The ISP-isolated samples were solubilized at pH 11.0 and recovered at pH 5.5 and 6.2. The ultimate pH of the ISP-isolated protein and meat paste was adjusted to 6.2 and 7.0. The ultimate pH in this article referred to the final pH of the extracted protein and meat paste. Higher reactive sulfhydryl content and surface hydrophobicity were found in the precipitation at pH 6.2 than at pH 5.5. However, various ultimate pH values showed no significant influence on the surface hydrophobicity. The hardness of gel, as measured by textural profile analysis, was improved using 6.2 as the precipitation pH compared with pH 5.5. The viscoelastic modulus (G΄) of gel pastes prior to the thermal gelation was higher with ISP treatment. However, lower G΄ was seen after thermal gelation compared with the control. Dynamic rheological measurement demonstrated a different gel-forming mechanism for protein precipitated at pH values of 5.5 and 6.2 compared with the meat paste. The cooking loss showed that the recovered protein failed to form a gel with good water-retention capacity unless the ultimate pH was adjusted to 7.0. Gels made from protein extracted by the ISP method had higher yellowness and lower redness values, probably due to protein denaturation. Precipitation at pH 6.2 formed a harder gel with lower water-retention ability than that at pH 5.5, and this result was possibly due to higher surface hydrophobicity and S-S bridge formation. Overall, network characteristics of ISP-treated protein gels were strongly dependent on precipitation pH and ultimate pH. © 2016

  13. Innovations in electronic services

    Directory of Open Access Journals (Sweden)

    Dagmara Wach

    2011-12-01

    Full Text Available Summarry Existence in electronic business has become increasingly difficult. High competition and considerable financial resources needed to enter electronic market are the problems of most micro and small sized enterprises, starting or developing their business. Nevertheless, there is a market niche for them, which can ensure success and grant partial financing of the business. This niche are small web projects, providing the customer with personalized service, hitting his tastes and meeting immediate needs. A projects that large websites are unable to perform. Financial sourcing of those projects comes from EU subsidies, in the framework of the Działanie 8.1. PO IG, 2007-2013.

  14. Electronic emission and electron guns

    International Nuclear Information System (INIS)

    Roy, Amitava

    2010-01-01

    This paper reviews the process of electron emission from metal surface. Although electrons move freely in conductors like metals, they normally do not leave the metal without some manipulation. In fact, heating and bombardment are the two primary ways in which electrons are emitted through the use of a heating element behind the cathode (termed thermionic emission) or as a result of bombardment with a beam of electrons, ions, or metastable atoms (termed secondary emission). Another important emission mechanism called Explosive Electron Emission (EEE) is also often used in various High Voltage Pulse Power Systems to generate very high current (few hundreds of kA) pulsed electron beams. The electron gun is the device in that it shoots off a continuous (or pulsed) stream of electrons. A brief idea about the evolution of the electron gun components and their basis of functioning are also discussed. (author)

  15. Sticker electronics

    KAUST Repository

    Hussain, Muhammad Mustafa; Torres Sevilla, Galo Andres; Diaz Cordero, Marlon Steven

    2017-01-01

    Electronic stickers may be manufactured on flexible substrates (110, 120, 130) as layers and packaged together. The package may then have an adhesive applied to one side to provide capability for sticking the electronic devices to surfaces

  16. ELECTRONIC SIGNATURES

    African Journals Online (AJOL)

    10332324

    "[to] promote the understanding and, acceptance of and growth in the number of electronic transactions .... Chapter III of the ECT Act is based on the UNCITRAL Model Law on Electronic. Commerce ... Communications Technology Law 146. 22.

  17. Electronic components

    CERN Document Server

    Colwell, Morris A

    1976-01-01

    Electronic Components provides a basic grounding in the practical aspects of using and selecting electronics components. The book describes the basic requirements needed to start practical work on electronic equipment, resistors and potentiometers, capacitance, and inductors and transformers. The text discusses semiconductor devices such as diodes, thyristors and triacs, transistors and heat sinks, logic and linear integrated circuits (I.C.s) and electromechanical devices. Common abbreviations applied to components are provided. Constructors and electronics engineers will find the book useful

  18. Understand electronics

    CERN Document Server

    Bishop, Owen

    2013-01-01

    Understand Electronics provides a readable introduction to the exciting world of electronics for the student or enthusiast with little previous knowledge. The subject is treated with the minimum of mathematics and the book is extensively illustrated.This is an essential guide for the newcomer to electronics, and replaces the author's best-selling Beginner's Guide to Electronics.The step-by-step approach makes this book ideal for introductory courses such as the Intermediate GNVQ.

  19. Electronic Commerce

    OpenAIRE

    Slavko Đerić

    2016-01-01

    Electronic commerce can be defined in different ways. Any definition helps to understand and explain that concept as better as possible.. Electronic commerce is a set of procedures and technologies that automate the tasks of financial transactions using electronic means. Also, according to some authors, electronic commerce is defined as a new concept, which is being developed and which includes process of buying and selling or exchanging products, services or information via computer networks...

  20. Electronic Publishing.

    Science.gov (United States)

    Lancaster, F. W.

    1989-01-01

    Describes various stages involved in the applications of electronic media to the publishing industry. Highlights include computer typesetting, or photocomposition; machine-readable databases; the distribution of publications in electronic form; computer conferencing and electronic mail; collaborative authorship; hypertext; hypermedia publications;…

  1. Building the electronic industry's roadmaps

    Science.gov (United States)

    Boulton, William R.

    1995-02-01

    JTEC panelists found a strong consistency among the electronics firms they visited: all the firms had clear visions or roadmaps for their research and development activities and had committed resources to ensure that they achieve targeted results. The overarching vision driving Japan's electronics industry is that of achieving market success through developing appealing, high-quality, low-cost consumer goods - ahead of the competition. Specifics of the vision include improving performance, quality, and portability of consumer electronics products. Such visions help Japanese companies define in detail the roadmaps they will follow to develop new and improved electronic packaging technologies.

  2. Electronic Recruitment at CERN

    CERN Multimedia

    2004-01-01

    The Human Resources Department switches to electronic recruitment. From now on whenever you are involved in a recruitment action you will receive an e-mail giving you access to a Web folder. Inside you will find a shortlist of applications drawn up by the Human Resources Department. This will allow you to consult the folder, at the same time as everyone else involved in the recruitment process, for the vacancy you are interested in. This new electronic recruitment system, known as e-RT, will be introduced in a presentation given at 10 a.m. on 11 February in the Main Auditorium. Implemented by AIS (Administrative Information Services) and the Human Resources Department, e-RT will cover vacancies open in all of CERN's recruitment programmes. The electronic application system was initially made available to technical students in July 2003. By December it was extended to summer students, fellows, associates and Local Staff. Geraldine Ballet from the Recruitment Service prefers e-RT to mountains of paper! The Hu...

  3. Sticker electronics

    KAUST Repository

    Hussain, Muhammad Mustafa

    2017-09-08

    Electronic stickers may be manufactured on flexible substrates (110, 120, 130) as layers and packaged together. The package may then have an adhesive applied to one side to provide capability for sticking the electronic devices to surfaces. The stickers can be wrappable, placed on surfaces, glued on walls or mirrors or wood or stone, and have electronics (112, 122, 132) which may or may not be ultrathin. Packaging for the electronic sticker can use polymer on cellulose manufacturing and/or three dimensional (3-D) printing. The electronic stickers may provide lighting capability, sensing capability, and/or recharging capabilities.

  4. Basic electronics

    CERN Document Server

    Holbrook, Harold D

    1971-01-01

    Basic Electronics is an elementary text designed for basic instruction in electricity and electronics. It gives emphasis on electronic emission and the vacuum tube and shows transistor circuits in parallel with electron tube circuits. This book also demonstrates how the transistor merely replaces the tube, with proper change of circuit constants as required. Many problems are presented at the end of each chapter. This book is comprised of 17 chapters and opens with an overview of electron theory, followed by a discussion on resistance, inductance, and capacitance, along with their effects on t

  5. Network resource management

    NARCIS (Netherlands)

    2009-01-01

    The invention provides real time dynamic resource management to improve end-to-end QoS by mobile devices regularly updating a resource availability server (RAS) with resource update information. Examples of resource update information are device battery status, available memory, session bandwidth,

  6. The Global Resource Nexus

    NARCIS (Netherlands)

    Ridder, M. de; Duijne, F. van; Jong, S. de; Jones, J.; Luit, E. van; Bekkers, F.F.; Auping, W.

    2014-01-01

    Supply and demand of resources are connected in a complex way. This interconnectivity has been framed as the global resource nexus and can conceivebly include all types of resources. This study focus on the nexus of five essential natural resources: land, food, energy, water and minerals. Together

  7. Knowledge and Natural Resources

    DEFF Research Database (Denmark)

    Bertelsen, Rasmus Gjedssø; Justinussen, Jens Christian Svabo

    2016-01-01

    Arctic economies are generally natural resource based economies, whether they are indigenous economies largely dependent on living on the land or industrialized economies depending on marine resources, mineral resources or fossil or renewable energy resources. However, the central role of knowledge...

  8. Electronic Commerce and Electronic Business

    Indian Academy of Sciences (India)

    R. Narasimhan (Krishtel eMaging) 1461 1996 Oct 15 13:05:22

    This special issue is motivated by the recent upsurge of research activity in the areas of electronic commerce and electronic business both in India and all over the world. The current ... Monte Carlo methods for pricing financial options are then.

  9. Electronic Government and Electronic Participation

    NARCIS (Netherlands)

    Tambouris, E; Scholl, H.J.; Janssen, M.F.W.H.A.; Wimmer, M.A.; Tarabanis, K; Gascó, M; Klievink, A.J.; Lindgren, I; Milano, M; Panagiotopoulos, P; Pardo, T.A.; Parycek, P; Sæbø, Ø

    2016-01-01

    Electronic government and electronic participation continue to transform the public sector and society worldwide and are constantly being transformed themselves by emerging information and communication technologies.This book presents papers from the 14th International Federation for Information

  10. Electronic Government and Electronic Participation

    NARCIS (Netherlands)

    Tambouris, E.; Scholl, H.J.; Janssen, M.F.W.H.A.; Wimmer, M.A.; Tarabanis, K.; Gascó, M.; Klievink, A.J.; Lindgren, I.; Milano, M.; Panagiotopoulos, P.; Pardo, T.A.; Parycek, P.; Sæbø, O.

    2015-01-01

    Electronic government and electronic participation continue to transform the public sector and society worldwide and are constantly being transformed themselves by emerging information and communication technologies. This book presents papers from the 14th International Federation for Information

  11. Electron Tree

    DEFF Research Database (Denmark)

    Appelt, Ane L; Rønde, Heidi S

    2013-01-01

    The photo shows a close-up of a Lichtenberg figure – popularly called an “electron tree” – produced in a cylinder of polymethyl methacrylate (PMMA). Electron trees are created by irradiating a suitable insulating material, in this case PMMA, with an intense high energy electron beam. Upon discharge......, during dielectric breakdown in the material, the electrons generate branching chains of fractures on leaving the PMMA, producing the tree pattern seen. To be able to create electron trees with a clinical linear accelerator, one needs to access the primary electron beam used for photon treatments. We...... appropriated a linac that was being decommissioned in our department and dismantled the head to circumvent the target and ion chambers. This is one of 24 electron trees produced before we had to stop the fun and allow the rest of the accelerator to be disassembled....

  12. `Twisted' electrons

    Science.gov (United States)

    Larocque, Hugo; Kaminer, Ido; Grillo, Vincenzo; Leuchs, Gerd; Padgett, Miles J.; Boyd, Robert W.; Segev, Mordechai; Karimi, Ebrahim

    2018-04-01

    Electrons have played a significant role in the development of many fields of physics during the last century. The interest surrounding them mostly involved their wave-like features prescribed by the quantum theory. In particular, these features correctly predict the behaviour of electrons in various physical systems including atoms, molecules, solid-state materials, and even in free space. Ten years ago, new breakthroughs were made, arising from the new ability to bestow orbital angular momentum (OAM) to the wave function of electrons. This quantity, in conjunction with the electron's charge, results in an additional magnetic property. Owing to these features, OAM-carrying, or twisted, electrons can effectively interact with magnetic fields in unprecedented ways and have motivated materials scientists to find new methods for generating twisted electrons and measuring their OAM content. Here, we provide an overview of such techniques along with an introduction to the exciting dynamics of twisted electrons.

  13. Australian uranium resources

    International Nuclear Information System (INIS)

    Battey, G.C.; Miezitis, Y.; McKay, A.D.

    1987-01-01

    Australia's uranium resources amount to 29% of the WOCA countries (world outside centrally-planned-economies areas) low-cost Reasonably Assured Resources and 28% of the WOCA countries low-cost Estimated Additional Resources. As at 1 January 1986, the Bureau of Mineral Resources estimated Australia's uranium resources as: (1) Cost range to US$80/kg U -Reasonably Assured Resources, 465 000 t U; Estimated Additional Resources, 256 000 t U; (2) Cost range US$80-130/kg U -Reasonably Assured Resources, 56 000 t U; Estimated Additional Resources, 127 000 t U. Most resources are contained in Proterozoic unconformity-related deposits in the Alligator Rivers uranium field in the Northern Territory (Jabiluka, Ranger, Koongarra, Nabarlek deposits) and the Proterozoic stratabound deposit at Olympic Dam on the Stuart Shelf in South Australia

  14. Human Resource Development in Hybrid Libraries

    OpenAIRE

    Prakasan, E. R.; Swarna, T.; Vijai Kumar, *

    2000-01-01

    This paper explores the human resources and development implications in hybrid libraries. Due to technological changes in libraries, which is a result of the proliferation of electronic resources, there has been a shift in workloads and workflow, requiring staff with different skills and educational backgrounds. Training of staff at all levels in information technology is the key to manage change, alleviate anxiety in the workplace and assure quality service in the libraries. Staff developmen...

  15. Students developing resources for students.

    Science.gov (United States)

    Pearce, Michael; Evans, Darrell

    2012-06-01

    The development of new technologies has provided medical education with the ability to enhance the student learning experience and meet the needs of changing curricula. Students quickly adapt to using multimedia learning resources, but these need to be well designed, learner-centred and interactive for students to become significantly engaged. One way to ensure that students become committed users and that resources become distinct elements of the learning cycle is to involve students in resource design and production. Such an approach enables resources to accommodate student needs and preferences, but also provides opportunities for them to develop their own teaching and training skills. The aim of the medical student research project was to design and produce an electronic resource that was focused on a particular anatomical region. The views of other medical students were used to decide what features were suitable for inclusion and the resulting package contained basic principles and clinical relevance, and used a variety of approaches such as images of cadaveric material, living anatomy movies and quizzes. The completed package was assessed using a survey matrix and found to compare well with commercially available products. Given the ever-diversifying arena of multimedia instruction and the ability of students to be fully conversant with technology, this project demonstrates that students are ideal participants and creators of multimedia resources. It is hoped that such an approach will help to further develop the skill base of students, but will also provide an avenue of developing packages that are student user friendly, and that are focused towards particular curricula requirements. © Blackwell Publishing Ltd 2012.

  16. Electronic Commerce

    Directory of Open Access Journals (Sweden)

    Slavko Đerić

    2016-12-01

    Full Text Available Electronic commerce can be defined in different ways. Any definition helps to understand and explain that concept as better as possible.. Electronic commerce is a set of procedures and technologies that automate the tasks of financial transactions using electronic means. Also, according to some authors, electronic commerce is defined as a new concept, which is being developed and which includes process of buying and selling or exchanging products, services or information via computer networks, including the Internet. Electronic commerce is not limited just to buying and selling, but it also includes all pre-sales and after-sales ongoing activities along the supply chain. Introducing electronic commerce, using the Internet and Web services in business, realizes the way to a completely new type of economy - internet economy.

  17. Advanced Electronics

    Science.gov (United States)

    2017-07-21

    AFRL-RV-PS- AFRL-RV-PS- TR-2017-0114 TR-2017-0114 ADVANCED ELECTRONICS Ashwani Sharma 21 Jul 2017 Interim Report APPROVED FOR PUBLIC RELEASE...NUMBER Advanced Electronics 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 62601F 6. AUTHOR(S) 5d. PROJECT NUMBER 4846 Ashwani Sharma 5e. TASK NUMBER...Approved for public release; distribution is unlimited. (RDMX-17-14919 dtd 20 Mar 2018) 13. SUPPLEMENTARY NOTES 14. ABSTRACT The Space Electronics

  18. Electron spectroscopy

    International Nuclear Information System (INIS)

    Hegde, M.S.

    1979-01-01

    An introduction to the various techniques in electron spectroscopy is presented. These techniques include: (1) UV Photoelectron spectroscopy, (2) X-ray Photoelectron spectroscopy, (3) Auger electron spectroscopy, (4) Electron energy loss spectroscopy, (5) Penning ionization spectroscopy and (6) Ion neutralization spectroscopy. The radiations used in each technique, the basis of the technique and the special information obtained in structure determination in atoms and molecules by each technique are summarised. (A.K.)

  19. Characterization of blend hydrogels based on plasticized starch/cellulose acetate/carboxymethyl cellulose synthesized by electron beam irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Senna, Magdy M., E-mail: magdysenna@hotmail.com [Radiation Chemistry Department, National Center for Radiation Research and Technology, Atomic Energy Authority, Cairo (Egypt); Mostafa, Abo El-Khair B. [Chemistry Department, College for Girls, Ain Shams University, Cairo (Egypt); Mahdy, Sanna R.; El-Naggar, Abdel Wahab M. [Radiation Chemistry Department, National Center for Radiation Research and Technology, Atomic Energy Authority, Cairo (Egypt)

    2016-11-01

    Highlights: • Semi-interpenetrating (IPN) blend hydrogels were synthesized by EB irradiation. • The hydrogels were based on starch/cellulose acetate/carboxymethyl cellulose blends. • The gelation, swelling, thermal and mechanical properties of hydrogels were studied. • The thermal stability was studied by determining kinetic energy by different methods. - Abstract: Blend hydrogels based on aqueous solutions of plasticized starch and different ratios of cellulose acetate (CA) and carboxymethyl cellulose (CMC) were prepared by electron beam irradiation (EB). The blends before and after EB irradiation were characterized by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The physico-chemical properties of blend hydrogels prepared by electron beam irradiation were improved compared to unirradiated blends.

  20. Characterization of blend hydrogels based on plasticized starch/cellulose acetate/carboxymethyl cellulose synthesized by electron beam irradiation

    International Nuclear Information System (INIS)

    Senna, Magdy M.; Mostafa, Abo El-Khair B.; Mahdy, Sanna R.; El-Naggar, Abdel Wahab M.

    2016-01-01

    Highlights: • Semi-interpenetrating (IPN) blend hydrogels were synthesized by EB irradiation. • The hydrogels were based on starch/cellulose acetate/carboxymethyl cellulose blends. • The gelation, swelling, thermal and mechanical properties of hydrogels were studied. • The thermal stability was studied by determining kinetic energy by different methods. - Abstract: Blend hydrogels based on aqueous solutions of plasticized starch and different ratios of cellulose acetate (CA) and carboxymethyl cellulose (CMC) were prepared by electron beam irradiation (EB). The blends before and after EB irradiation were characterized by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). The physico-chemical properties of blend hydrogels prepared by electron beam irradiation were improved compared to unirradiated blends.

  1. Polymer electronics

    CERN Document Server

    Hsin-Fei, Meng

    2013-01-01

    Polymer semiconductor is the only semiconductor that can be processed in solution. Electronics made by these flexible materials have many advantages such as large-area solution process, low cost, and high performance. Researchers and companies are increasingly dedicating time and money in polymer electronics. This book focuses on the fundamental materials and device physics of polymer electronics. It describes polymer light-emitting diodes, polymer field-effect transistors, organic vertical transistors, polymer solar cells, and many applications based on polymer electronics. The book also disc

  2. Electronics Industry

    National Research Council Canada - National Science Library

    Bell, Robert; Carroll-Garrison, Martina; Donovan, Daniel; Fisher, John; Guemmer, Paul; Harms, Robert; Kelly, Timothy; Love, Mattie; McReynolds, James; Ward, Ralph

    2006-01-01

    .... Government action to preserve strategic access to semiconductor producers is clearly needed to ensure DoD electronic systems can be built without compromising sensitive technology, though every...

  3. Microfluidic electronics.

    Science.gov (United States)

    Cheng, Shi; Wu, Zhigang

    2012-08-21

    Microfluidics, a field that has been well-established for several decades, has seen extensive applications in the areas of biology, chemistry, and medicine. However, it might be very hard to imagine how such soft microfluidic devices would be used in other areas, such as electronics, in which stiff, solid metals, insulators, and semiconductors have previously dominated. Very recently, things have radically changed. Taking advantage of native properties of microfluidics, advances in microfluidics-based electronics have shown great potential in numerous new appealing applications, e.g. bio-inspired devices, body-worn healthcare and medical sensing systems, and ergonomic units, in which conventional rigid, bulky electronics are facing insurmountable obstacles to fulfil the demand on comfortable user experience. Not only would the birth of microfluidic electronics contribute to both the microfluidics and electronics fields, but it may also shape the future of our daily life. Nevertheless, microfluidic electronics are still at a very early stage, and significant efforts in research and development are needed to advance this emerging field. The intention of this article is to review recent research outcomes in the field of microfluidic electronics, and address current technical challenges and issues. The outlook of future development in microfluidic electronic devices and systems, as well as new fabrication techniques, is also discussed. Moreover, the authors would like to inspire both the microfluidics and electronics communities to further exploit this newly-established field.

  4. Electron holography

    CERN Document Server

    Tonomura, Akira

    1993-01-01

    Holography was devised for breaking through the resolution limit of electron microscopes The advent of a "coherent" field emission electron beam has enabled the use of Electron Holography in various areas of magnetic domain structures observation, fluxon observation in superconductors, and fundamental experiments in physics which have been inaccessible using other techniques After examining the fundamentals of electron holography and its applications to the afore mentioned fields, a detailed discussion of the Aharonov-Bohm effect and the related experiments is presented Many photographs and illustrations are included to elucidate the text

  5. Electronic Publishing Approaches to Curriculum: Videotex, Teletext and Databases.

    Science.gov (United States)

    Aumente, Jerome

    1986-01-01

    Describes the Journalism Resources Institute (JRI) of Rutgers University in terms of its administrative organization, computer resources, computer facilities use, involvement in electronic publishing, use of the Dow Jones News/Retrieval Database, curricular options, and professional continuing education. (AYC)

  6. When resources get sparse

    DEFF Research Database (Denmark)

    Graungaard, Anette Hauskov; Andersen, John Sahl; Skov, Liselotte

    2011-01-01

    resources through positive cognitive reappraisals of their circumstances, the consequences of those circumstances and their coping possibilities. Nine main coping strategies were identified constituting transformative pathways in resource-creation. A theory of resource-creation is proposed as an addition...... coped with parenting a disabled child and how they maintained their energy and personal resources. We explored parents' experiences, coping and resources over a two-year period after their child was diagnosed with a severely disabling condition using a qualitative, longitudinal approach. Findings were...... to the current understanding of coping and the role of positive emotions. Coping and resources were found to be closely interrelated and portals of intervention are discussed....

  7. The electron

    International Nuclear Information System (INIS)

    Hestenes, David; Weingartshofer, Antonio

    1991-01-01

    The stupendous successes of the Dirac equation and quantum electro-dynamics have established the electron as the best understood of the fundamental constituents of matter. Nevertheless, physicists agree that the electron still has secrets to reveal. Moreover, powerful new theoretical and experimental tools for probing those secrets have been sharpened during the last decade. This workshop was organized to bring theorists and experimentalists together to discuss their common goal of knowing the electron. Present state and future prospects for progress toward that goal are here described. The theoretical papers encompass a wide range of views on the electron. Several argue that the 'Zitter-bewegung' is more than a mathematical peculiarity of the Dirac equation, that it may well be a real physical phenomenon and worthy of serious study, theoretically and experimentally. Besides generating the electron spin and magnetic moment, the 'Zitterbewegung' may be a vital clue to electron structure and self-interaction. Some of the papers employ a radical new formulation of the Dirac theory which reveals a hidden geo-metric structure in the theory that supports a 'Zitterbewegung' inter-pretation. For the last half century the properties of electrons have been probed primarily by scattering experiments at ever higher energies. Recently, however, two powerful new experimental techniques have emerged capable of giving alternative experimental views of the electron. First, techniques for confining single electrons for long term study have led to the most accurate measurements of the electron magnetic moment. Second, the interaction of high intensity laser fields with atoms and electrons have revealed striking new phenomena such as multiphoton ionization. refs.; figs.; tabs

  8. Sustainable polymers from renewable resources.

    Science.gov (United States)

    Zhu, Yunqing; Romain, Charles; Williams, Charlotte K

    2016-12-14

    Renewable resources are used increasingly in the production of polymers. In particular, monomers such as carbon dioxide, terpenes, vegetable oils and carbohydrates can be used as feedstocks for the manufacture of a variety of sustainable materials and products, including elastomers, plastics, hydrogels, flexible electronics, resins, engineering polymers and composites. Efficient catalysis is required to produce monomers, to facilitate selective polymerizations and to enable recycling or upcycling of waste materials. There are opportunities to use such sustainable polymers in both high-value areas and in basic applications such as packaging. Life-cycle assessment can be used to quantify the environmental benefits of sustainable polymers.

  9. Solar Resource Assessment

    Energy Technology Data Exchange (ETDEWEB)

    Renne, D.; George, R.; Wilcox, S.; Stoffel, T.; Myers, D.; Heimiller, D.

    2008-02-01

    This report covers the solar resource assessment aspects of the Renewable Systems Interconnection study. The status of solar resource assessment in the United States is described, and summaries of the availability of modeled data sets are provided.

  10. Hydrography - Water Resources

    Data.gov (United States)

    NSGIC Education | GIS Inventory — A Water Resource is a DEP primary facility type related to the Water Use Planning Program. The sub-facility types related to Water Resources that are included are:...

  11. Current Resource Imagery Projects

    Data.gov (United States)

    Farm Service Agency, Department of Agriculture — Map showing coverage of current Resource imagery projects. High resolution/large scale Resource imagery is typically acquired for the U.S. Forest Service and other...

  12. Vermont Natural Resources Atlas

    Data.gov (United States)

    Vermont Center for Geographic Information — The purpose of the�Natural Resources Atlas�is to provide geographic information about environmental features and sites that the Vermont Agency of Natural Resources...

  13. Resources, Technology, and Strategy

    DEFF Research Database (Denmark)

    Resources, Technology and Strategy brings together contributors from Europe, North America and Asia to consider the strategic relationship between technology and other resources, such as production capabilities, marketing prowess, finance and organisational culture. Throughout the book...

  14. Printed Electronics

    Science.gov (United States)

    Korkut, Sibel (Inventor); Chiang, Katherine S. (Inventor); Crain, John M. (Inventor); Aksay, Ilhan A. (Inventor); Lettow, John S. (Inventor); Chen, Chuan-Hua (Inventor); Prud'Homme, Robert K. (Inventor)

    2018-01-01

    Printed electronic device comprising a substrate onto at least one surface of which has been applied a layer of an electrically conductive ink comprising functionalized graphene sheets and at least one binder. A method of preparing printed electronic devices is further disclosed.

  15. Defense Human Resources Activity > PERSEREC

    Science.gov (United States)

    Skip to main content (Press Enter). Toggle navigation Defense Human Resources Activity Search Search Defense Human Resources Activity: Search Search Defense Human Resources Activity: Search Defense Human Resources Activity U.S. Department of Defense Defense Human Resources Activity Overview

  16. Cultural Resource Predictive Modeling

    Science.gov (United States)

    2017-10-01

    CR cultural resource CRM cultural resource management CRPM Cultural Resource Predictive Modeling DoD Department of Defense ESTCP Environmental...resource management ( CRM ) legal obligations under NEPA and the NHPA, military installations need to demonstrate that CRM decisions are based on objective...maxim “one size does not fit all,” and demonstrate that DoD installations have many different CRM needs that can and should be met through a variety

  17. Reasoning abstractly about resources

    Science.gov (United States)

    Clement, B.; Barrett, A.

    2001-01-01

    r describes a way to schedule high level activities before distributing them across multiple rovers in order to coordinate the resultant use of shared resources regardless of how each rover decides how to perform its activities. We present an algorithm for summarizing the metric resource requirements of an abstract activity based n the resource usages of its potential refinements.

  18. Save Our Water Resources.

    Science.gov (United States)

    Bromley, Albert W.

    The purpose of this booklet, developed as part of Project SOAR (Save Our American Resources), is to give Scout leaders some facts about the world's resources, the sources of water pollution, and how people can help in obtaining solutions. Among the topics discussed are the world's water resources, the water cycle, water quality, sources of water…

  19. The cellulose resource matrix

    NARCIS (Netherlands)

    Keijsers, E.R.P.; Yilmaz, G.; Dam, van J.E.G.

    2013-01-01

    The emerging biobased economy is causing shifts from mineral fossil oil based resources towards renewable resources. Because of market mechanisms, current and new industries utilising renewable commodities, will attempt to secure their supply of resources. Cellulose is among these commodities, where

  20. Ohio Water Resources Council

    Science.gov (United States)

    Ohio.gov State Agencies | Online Services Twitter YouTube EPA IMAGE Ohio Water Resources Committee Ohio enjoys abundant water resources. Few states enjoy as many streams, rivers, lakes and wetlands as Ohio. Numerous agencies and organizations are involved in protecting Ohio's valuable water resources

  1. Electronic Information – Threat or Challenge to Librarians and ...

    African Journals Online (AJOL)

    Electronic Information – Threat or Challenge to Librarians and Library Buildings. ... electronic resources because as new things and methods emerge, they exist ... that world trends in the paper industry and Internet use do not justify the fears ...

  2. Resources to Manage a Private Practice.

    Science.gov (United States)

    Aigner, John; Cheek, Fredricka; Donati, Georgia; Zuravicky, Dori

    1997-01-01

    Includes four theme articles: "The Digital Toolkit: Electronic Necessities for Private Practice" (John Aigner); "Organizing a Private Practice: Forms, Fees, and Physical Set-up (Fredricka Cheek); "Career Development Resources: Guidelines for Setting Up a Private Practice Library" (Georgia Donati); and "Books to…

  3. Digital electronics

    CERN Document Server

    Morris, John

    2013-01-01

    An essential companion to John C Morris's 'Analogue Electronics', this clear and accessible text is designed for electronics students, teachers and enthusiasts who already have a basic understanding of electronics, and who wish to develop their knowledge of digital techniques and applications. Employing a discovery-based approach, the author covers fundamental theory before going on to develop an appreciation of logic networks, integrated circuit applications and analogue-digital conversion. A section on digital fault finding and useful ic data sheets completes th

  4. Electronic diagrams

    CERN Document Server

    Colwell, Morris A

    1976-01-01

    Electronic Diagrams is a ready reference and general guide to systems and circuit planning and in the preparation of diagrams for both newcomers and the more experienced. This book presents guidelines and logical procedures that the reader can follow and then be equipped to tackle large complex diagrams by recognition of characteristic 'building blocks' or 'black boxes'. The goal is to break down many of the barriers that often seem to deter students and laymen in learning the art of electronics, especially when they take up electronics as a spare time occupation. This text is comprised of nin

  5. Polymer electronics

    CERN Document Server

    Geoghegan, Mark

    2013-01-01

    Polymer electronics is the science behind many important new developments in technology, such as the flexible electronic display (e-ink) and many new developments in transistor technology. Solar cells, light-emitting diodes, and transistors are all areas where plastic electronics is likely to, or is already having, a serious impact on our daily lives. With polymer transistors and light-emitting diodes now being commercialised, there is a clear need for a pedagogic text thatdiscusses the subject in a clear and concise fashion suitable for senior undergraduate and graduate students. The content

  6. Starting electronics

    CERN Document Server

    Brindley, Keith

    2005-01-01

    Starting Electronics is unrivalled as a highly practical introduction for hobbyists, students and technicians. Keith Brindley introduces readers to the functions of the main component types, their uses, and the basic principles of building and designing electronic circuits. Breadboard layouts make this very much a ready-to-run book for the experimenter; and the use of multimeter, but not oscilloscopes, puts this practical exploration of electronics within reach of every home enthusiast's pocket. The third edition has kept the simplicity and clarity of the original. New material

  7. Stretchable electronics

    CERN Document Server

    Someya, Takao

    2012-01-01

    With its comprehensive coverage this handbook and ready reference brings together some of the most outstanding scientists in the field to lay down the undisputed knowledge on how to make electronics stretchable.As such, it focuses on gathering and evaluating the materials, designs, models and technologies that enable the fabrication of fully elastic electronic devices which can sustain high strain. Furthermore, it provides a review of those specific applications that directly benefit from highly compliant electronics, including transistors, photonic devices and sensors. In addition to stre

  8. Electron optics

    CERN Document Server

    Grivet, Pierre; Bertein, F; Castaing, R; Gauzit, M; Septier, Albert L

    1972-01-01

    Electron Optics, Second English Edition, Part I: Optics is a 10-chapter book that begins by elucidating the fundamental features and basic techniques of electron optics, as well as the distribution of potential and field in electrostatic lenses. This book then explains the field distribution in magnetic lenses; the optical properties of electrostatic and magnetic lenses; and the similarities and differences between glass optics and electron optics. Subsequent chapters focus on lens defects; some electrostatic lenses and triode guns; and magnetic lens models. The strong focusing lenses and pris

  9. Electronic identity

    CERN Document Server

    de Andrade, Norberto Nuno Gomes; Argles, David

    2014-01-01

    With the increasing availability of electronic services, security and a reliable means by which identity is verified is essential.Written by Norberto Andrade the first chapter of this book provides an overview of the main legal and regulatory aspects regarding electronic identity in Europe and assesses the importance of electronic identity for administration (public), business (private) and, above all, citizens. It also highlights the role of eID as a key enabler of the economy.In the second chapter Lisha Chen-Wilson, David Argles, Michele Schiano di Zenise and Gary Wills discuss the user-cent

  10. Self managing experiment resources

    International Nuclear Information System (INIS)

    Stagni, F; Ubeda, M; Charpentier, P; Tsaregorodtsev, A; Romanovskiy, V; Roiser, S; Graciani, R

    2014-01-01

    Within this paper we present an autonomic Computing resources management system, used by LHCb for assessing the status of their Grid resources. Virtual Organizations Grids include heterogeneous resources. For example, LHC experiments very often use resources not provided by WLCG, and Cloud Computing resources will soon provide a non-negligible fraction of their computing power. The lack of standards and procedures across experiments and sites generated the appearance of multiple information systems, monitoring tools, ticket portals, etc... which nowadays coexist and represent a very precious source of information for running HEP experiments Computing systems as well as sites. These two facts lead to many particular solutions for a general problem: managing the experiment resources. In this paper we present how LHCb, via the DIRAC interware, addressed such issues. With a renewed Central Information Schema hosting all resources metadata and a Status System (Resource Status System) delivering real time information, the system controls the resources topology, independently of the resource types. The Resource Status System applies data mining techniques against all possible information sources available and assesses the status changes, that are then propagated to the topology description. Obviously, giving full control to such an automated system is not risk-free. Therefore, in order to minimise the probability of misbehavior, a battery of tests has been developed in order to certify the correctness of its assessments. We will demonstrate the performance and efficiency of such a system in terms of cost reduction and reliability.

  11. Resource Structuring and Ambidexterity

    DEFF Research Database (Denmark)

    Ma, Yucheng; Li, Peter Ping

    -shaped effect on organizational ambidexterity in new ventures. Further, because of the traditional culture and economic transition characteristics, new ventures actively leverage managerial ties as key social relations to obtain special resources or nurture business transactions. We propose that ties with other......Focusing on how resource structuring mechanisms and managerial ties influence organizational ambidexterity of new ventures in emerging economy, this study explores the effects of resource structuring mechanisms (i.e., resource acquiring and resource accumulating) on organizational ambidexterity....... It further examines the moderating effects of managerial ties, (i.e., ties with other firms and ties with the government) on the above relationships. Survey data from China¡¯s 202 new ventures demonstrates that the resource acquiring has an inverted U-shaped effect whereas the resource accumulating has a U...

  12. Looking for Guidelines for the Production of Electronic Textbooks.

    Science.gov (United States)

    Landoni, M.; Wilson, R.; Gibb, F.

    2001-01-01

    Reports the results of two studies of electronic book production, including production on the World Wide Web, and explains EBONI (Electronic Books On-screen Interface) that focuses on the evaluation of electronic resources and compiling guidelines for publishing electronic materials on the Internet for the United Kingdom higher education…

  13. Paper electronics.

    Science.gov (United States)

    Tobjörk, Daniel; Österbacka, Ronald

    2011-05-03

    Paper is ubiquitous in everyday life and a truly low-cost substrate. The use of paper substrates could be extended even further, if electronic applications would be applied next to or below the printed graphics. However, applying electronics on paper is challenging. The paper surface is not only very rough compared to plastics, but is also porous. While this is detrimental for most electronic devices manufactured directly onto paper substrates, there are also approaches that are compatible with the rough and absorptive paper surface. In this review, recent advances and possibilities of these approaches are evaluated and the limitations of paper electronics are discussed. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. Electron Microprobe

    Data.gov (United States)

    Federal Laboratory Consortium — The JEOL JXA-8600 is a conventional hairpin filament thermal emission electron microprobe that is more than 20 years old. It is capable of performing qualitative and...

  15. Electronic Aggression

    Centers for Disease Control (CDC) Podcasts

    Aggression is no longer limited to the school yard. New forms of electronic media, such as blogs, instant messaging, chat rooms, email, text messaging, and the internet are providing new arenas for youth violence to occur.

  16. Electron Emitters

    National Research Council Canada - National Science Library

    Tzeng, Yonhua

    2002-01-01

    When two carbon-nanotube coated electrodes are placed at a small distance from each other, electron emission from carbon nanotubes allows a DC or AC electrical current to flow between these two electrodes...

  17. Electronic plants

    Science.gov (United States)

    Stavrinidou, Eleni; Gabrielsson, Roger; Gomez, Eliot; Crispin, Xavier; Nilsson, Ove; Simon, Daniel T.; Berggren, Magnus

    2015-01-01

    The roots, stems, leaves, and vascular circuitry of higher plants are responsible for conveying the chemical signals that regulate growth and functions. From a certain perspective, these features are analogous to the contacts, interconnections, devices, and wires of discrete and integrated electronic circuits. Although many attempts have been made to augment plant function with electroactive materials, plants’ “circuitry” has never been directly merged with electronics. We report analog and digital organic electronic circuits and devices manufactured in living plants. The four key components of a circuit have been achieved using the xylem, leaves, veins, and signals of the plant as the template and integral part of the circuit elements and functions. With integrated and distributed electronics in plants, one can envisage a range of applications including precision recording and regulation of physiology, energy harvesting from photosynthesis, and alternatives to genetic modification for plant optimization. PMID:26702448

  18. Electronic Elections

    DEFF Research Database (Denmark)

    Schürmann, Carsten

    2009-01-01

    Electronic voting technology is a two edged sword. It comes with many risks but brings also many benefits. Instead of flat out rejecting the technology as uncontrollably dangerous, we advocate in this paper a different technological angle that renders electronic elections trustworthy beyond...... the usual levels of doubt. We exploit the trust that voters currently have into the democratic process and model our techniques around that observation accordingly. In particular, we propose a technique of trace emitting computations to record the individual steps of an electronic voting machine...... for a posteriori validation on an acceptably small trusted computing base. Our technology enables us to prove that an electronic elections preserves the voter’s intent, assuming that the voting machine and the trace verifier are independent....

  19. Electronic commerce

    OpenAIRE

    Zvolánková, Pavla

    2010-01-01

    The thesis deals with a description of electronic commerce from its beginning up to present situation in this area. It explains basic terms connected with electronic commerce and it summarizes the relevant legislation. Moreover it describes e-contracts and rights and duties of both contractual parties. The main view is the view of Internet retailer, which is reflected in the practical part focused on concrete problems of retailers.

  20. Printed Electronics

    Science.gov (United States)

    Wade, Jessica; Hollis, Joseph Razzell; Wood, Sebastian

    2018-04-01

    The combination of printing technology with manufacturing electronic devices enables a new paradigm of printable electronics, where 'smart' functionality can be readily incorporated into almost any product at low cost. Over recent decades, rapid progress has been made in this field, which is now emerging into the industrial andcommercial realm. However, successful development and commercialisation on a large scale presents some significant technical challenges. For fully-printable electronic systems, all the component parts must be deposited from solutions (inks), requiring the development of new inorganic, organic and hybrid materials.A variety of traditional printing techniques are being explored and adapted forprinting these new materials in ways that result in the best performing electronicdevices. Whilst printed electronics research has initially focused on traditional typesof electronic device such as light-emitting diodes, transistors, and photovoltaics, it is increasingly apparent that a much wider range of applications can be realised. The soft and stretchable nature of printable materials makes them perfect candidates forbioelectronics, resulting in a wealth of research looking at biocompatible printable inks and biosensors. Regardless of application, the properties of printed electronicmaterials depend on the chemical structures, processing conditions, device architecture,and operational conditions, the complex inter-relationships of which aredriving ongoing research. We focus on three particular 'hot topics', where attention is currently focused: novel materials, characterisation techniques, and device stability. With progress advancing very rapidly, printed electronics is expected to grow over the next decade into a key technology with an enormous economic and social impact.

  1. Where Doctors Read Health Information Resources and Their ...

    African Journals Online (AJOL)

    Resources Media Preferences. Obianuju E. ... The survey research design was adopted for the study. ... media of assessing health information are the internet, electronic databases, textbooks, journals and .... for Social Sciences (SPSS).

  2. Improving the Status of Human and Material Resources in Public ...

    African Journals Online (AJOL)

    Improving the Status of Human and Material Resources in Public Primary School in Oyo States ... the Millennium Development Goals project in the State. ... libraries, well-equipped first aid centres, adequate electronically projected instructional ...

  3. Lightning Safety Tips and Resources

    Science.gov (United States)

    ... Services Careers Contact Us Glossary Safety National Program Lightning Safety Tips and Resources Weather.gov > Safety > Lightning Safety Tips and Resources Lightning Resources Lightning strikes ...

  4. Numerical simulation of transient moisture and temperature distribution in polycarbonate and aluminum electronic enclosures

    DEFF Research Database (Denmark)

    Shojaee Nasirabadi, Parizad; Jabbaribehnam, Mirmasoud; Hattel, Jesper Henri

    2016-01-01

    The challenge of developing a reliable electronic product requires huge amounts of resources and knowledge. Temperature and thermal features directly affect the life of electronic products. Furthermore, moisture can be damaging for electronic components. Nowadays, computational fluid dynamics (CF...

  5. Risk Profile May Affect Search Process but Not Results. A review of: McKibbon, K. Ann, Douglas B. Fridsma, and Rebecca S. Crowley. “How Primary Care Physicians’ Attitudes Toward Risk and Uncertainty Affect Their Use of Electronic Information Resources.” Journal of the Medical Library Association 95.2 (2007: 138‐46, e49‐50. 10 Nov. 2007 .

    Directory of Open Access Journals (Sweden)

    Gale G. Hannigan

    2007-12-01

    Full Text Available Objective – To compare the use, in terms of process and outcomes, of electronic information resources by primary care physicians with different risk profiles and comfort with uncertainty.Design – Survey, and observation using “think‐aloud” method.Setting – Physicians’ offices.Subjects – Canadian and U.S. primary carephysicians who report seeing patients in clinic settings.Methods – Volunteers were recruited from personal contacts and the list of physicianswho rate current studies for the McMaster Online Rating of Evidence (MORE project. Physicians completed the Pearson scale to measure attitude toward risk and the Gerrity scale to measure comfort with uncertainty, and those who scored at the extremes of each of these two scales were included in the study (n=25, resulting in four groups (risk‐seeking, risk‐avoiding, uncertainty‐stressed, uncertainty unstressed. One researcher observed each of these physicians in their offices for an hour during which they completed questionnaires about their computer skills and familiarity with resources, answered multiple‐choice clinical questions, and indicated level of certainty with regard to those answers (scale of 0 to 100%. Physicians also chose two of the clinical questions to answer using their own resources. The think‐aloud method was employed, and transcripts were coded and analyzed.Main results – The study analysis included two comparisons: risk‐seeking (11 subjects versus risk‐avoiding (11 subjects physicians,and uncertainty‐stressed (11 subjects versus uncertainty‐unstressed (10 subjects physicians. Most physicians were included in both sets of analyses. The researchers found no association of risk attitude and uncertainty stress with computer skills nor with familiarity and use of specific information resources (Internet, MEDLINE, PIER, Clinical Evidence, and UpToDate. No differences were found for the following outcomes: time spent searching, answers correct

  6. World energy resources

    Directory of Open Access Journals (Sweden)

    Clerici A.

    2015-01-01

    Full Text Available As energy is the main “fuel” for social and economic development and since energy-related activities have significant environmental impacts, it is important for decision-makers to have access to reliable and accurate data in an user-friendly format. The World Energy Council (WEC has for decades been a pioneer in the field of energy resources and every three years publishes its flagship report Survey of Energy Resources. A commented analysis in the light of latest data summarized in such a report, World Energy Resources (WER 2013, is presented together with the evolution of the world energy resources over the last twenty years.

  7. World energy resources

    Science.gov (United States)

    Clerici, A.; Alimonti, G.

    2015-08-01

    As energy is the main "fuel" for social and economic development and since energy-related activities have significant environmental impacts, it is important for decision-makers to have access to reliable and accurate data in an user-friendly format. The World Energy Council (WEC) has for decades been a pioneer in the field of energy resources and every three years publishes its flagship report Survey of Energy Resources. A commented analysis in the light of latest data summarized in such a report, World Energy Resources (WER) 2013, is presented together with the evolution of the world energy resources over the last twenty years.

  8. Sharing network resources

    CERN Document Server

    Parekh, Abhay

    2014-01-01

    Resource Allocation lies at the heart of network control. In the early days of the Internet the scarcest resource was bandwidth, but as the network has evolved to become an essential utility in the lives of billions, the nature of the resource allocation problem has changed. This book attempts to describe the facets of resource allocation that are most relevant to modern networks. It is targeted at graduate students and researchers who have an introductory background in networking and who desire to internalize core concepts before designing new protocols and applications. We start from the fun

  9. 2005 resource options report

    International Nuclear Information System (INIS)

    Morris, T.

    2005-01-01

    This resource options report (ROR) fulfils regulatory requirements in British Columbia's two-year resource planning process. It identifies a wide range of resources and technologies that could be used to meet BC Hydro's future electricity demand. As such, it facilitates a transparent public review of resource options which include both supply-side and demand-side options. The resource options that will be used in the 2005 integrated electricity plan (IEP) were characterized. This ROR also documents where there is a general agreement or disagreement on the resource type characterization, based on the First Nations and Stakeholder engagement. BC Hydro used current information to provide realistic ranges on volume and cost to characterize environmental and social attributes. The BC Hydro system was modelled to assess the benefit and cost of various resource options. The information resulting from this ROR and IEP will help in making decisions on how to structure competitive acquisition calls and to determine the level of transmission services needed to advance certain BC Hydro projects. The IEP forecasts the nature and quantity of domestic resources required over the next 20 years. A strategic direction on how those needs will be met has been created to guide the management of BC Hydro's energy resources. Supply-side options include near-commercial technologies such as energy storage, ocean waves, tidal, fuel cells and integrated coal gasification combined cycle technology. Supply-side options also include natural gas, coal, biomass, geothermal, wind, and hydro. 120 refs., 39 tabs., 21 figs., 6 appendices

  10. Emotional Intelligence Research within Human Resource Development Scholarship

    Science.gov (United States)

    Farnia, Forouzan; Nafukho, Fredrick Muyia

    2016-01-01

    Purpose: The purpose of this study is to review and synthesize pertinent emotional intelligence (EI) research within the human resource development (HRD) scholarship. Design/methodology/approach: An integrative review of literature was conducted and multiple electronic databases were searched to find the relevant resources. Using the content…

  11. Utilisation of Online Resources among Undergraduates in Nigerian ...

    African Journals Online (AJOL)

    Electronic book (e-book) was mostly utilized as against Ejournals and E-thesis, while mobile phones and cybercafés remain the channels used in accessing online resources. it was discovered that incessant power supply, slow Internet connectivity and lack of time to access the information resources are constraints to ...

  12. Molecular Electronics

    DEFF Research Database (Denmark)

    Jennum, Karsten Stein

    This thesis includes the synthesis and characterisation of organic compounds designed for molecular electronics. The synthesised organic molecules are mainly based on two motifs, the obigo(phenyleneethynylenes) (OPE)s and tetrathiafulvalene (TTF) as shown below. These two scaffolds (OPE and TTF......) are chemically merged together to form cruciform-like structures that are an essential part of the thesis. The cruciform molecules were subjected to molecular conductance measurements to explore their capability towards single-crystal field-effect transistors (Part 1), molecular wires, and single electron......, however, was obtained by a study of a single molecular transistor. The investigated OPE5-TTF compound was captured in a three-terminal experiment, whereby manipulation of the molecule’s electronic spin was possible in different charge states. Thus, we demonstrated how the cruciform molecules could...

  13. Electron tube

    Science.gov (United States)

    Suyama, Motohiro [Hamamatsu, JP; Fukasawa, Atsuhito [Hamamatsu, JP; Arisaka, Katsushi [Los Angeles, CA; Wang, Hanguo [North Hills, CA

    2011-12-20

    An electron tube of the present invention includes: a vacuum vessel including a face plate portion made of synthetic silica and having a surface on which a photoelectric surface is provided, a stem portion arranged facing the photoelectric surface and made of synthetic silica, and a side tube portion having one end connected to the face plate portion and the other end connected to the stem portion and made of synthetic silica; a projection portion arranged in the vacuum vessel, extending from the stem portion toward the photoelectric surface, and made of synthetic silica; and an electron detector arranged on the projection portion, for detecting electrons from the photoelectric surface, and made of silicon.

  14. Spin electronics

    CERN Document Server

    Buhrman, Robert; Daughton, James; Molnár, Stephan; Roukes, Michael

    2004-01-01

    This report is a comparative review of spin electronics ("spintronics") research and development activities in the United States, Japan, and Western Europe conducted by a panel of leading U.S. experts in the field. It covers materials, fabrication and characterization of magnetic nanostructures, magnetism and spin control in magnetic nanostructures, magneto-optical properties of semiconductors, and magnetoelectronics and devices. The panel's conclusions are based on a literature review and a series of site visits to leading spin electronics research centers in Japan and Western Europe. The panel found that Japan is clearly the world leader in new material synthesis and characterization; it is also a leader in magneto-optical properties of semiconductor devices. Europe is strong in theory pertaining to spin electronics, including injection device structures such as tunneling devices, and band structure predictions of materials properties, and in development of magnetic semiconductors and semiconductor heterost...

  15. Electronic Commerce

    Energy Technology Data Exchange (ETDEWEB)

    Laird, N. [NRG Information Services Inc., Calgary, AB (Canada)

    1995-11-01

    The concept of electronic commerce in the gas industry was discussed. It was defined as the integration of communication technology, advanced information processing capability and business standards, to improve effectiveness of the business process. Examples of electronic data interchange from the automotive, airline, and banking industry were given. The objective of using this technology in the gas industry was described as the provision of one electronic facility to make seamless contractual and operational arrangements for moving natural gas across participating pipelines. The benefit of seamless integration - one readily available standard system used by several companies - was highlighted. A list of value-added services such as the free movement of bulletins, directories, nominations,and other documents was provided.

  16. Electron accelerator

    International Nuclear Information System (INIS)

    Abramyan.

    1981-01-01

    The USSR produces an electron accelerator family of a simple design powered straight from the mains. The specifications are given of accelerators ELITA-400, ELITA-3, ELT-2, TEUS-3 and RIUS-5 with maximum electron energies of 0.3 to 5 MeV, a mean power of 10 to 70 kW operating in both the pulsed and the continuous (TEUS-3) modes. Pulsed accelerators ELITA-400 and ELITA-3 and RIUS-5 in which TESLA resonance transformers are used are characterized by their compact size. (Ha)

  17. Electronic cigarette

    OpenAIRE

    Wang, Tao

    2016-01-01

    As we know E-cigarette is becoming increasingly popular all over the world. It is a new product that the most of smoking people would like to buy and use. However, we are not realizing advantages and disadvantages of e-cigarette clearly. My objective was to research the development of electronic cigarette whether it is under control or a good way of marketing. The thesis has two main parts. They include answers to questions what is electronic cigarette and how to manage the whole industry...

  18. Gaseous Electronics Tables, Atoms, and Molecules

    CERN Document Server

    Raju, Gorur Govinda

    2011-01-01

    With the constant emergence of new research and application possibilities, gaseous electronics is more important than ever in disciplines including engineering (electrical, power, mechanical, electronics, and environmental), physics, and electronics. The first resource of its kind, Gaseous Electronics: Tables, Atoms, and Molecules fulfills the author's vision of a stand-alone reference to condense 100 years of research on electron-neutral collision data into one easily searchable volume. It presents most--if not all--of the properly classified experimental results that scientists, researchers,

  19. Reliability criteria selection for integrated resource planning

    International Nuclear Information System (INIS)

    Ruiu, D.; Ye, C.; Billinton, R.; Lakhanpal, D.

    1993-01-01

    A study was conducted on the selection of a generating system reliability criterion that ensures a reasonable continuity of supply while minimizing the total costs to utility customers. The study was conducted using the Institute for Electronic and Electrical Engineers (IEEE) reliability test system as the study system. The study inputs and results for conditions and load forecast data, new supply resources data, demand-side management resource data, resource planning criterion, criterion value selection, supply side development, integrated resource development, and best criterion values, are tabulated and discussed. Preliminary conclusions are drawn as follows. In the case of integrated resource planning, the selection of the best value for a given type of reliability criterion can be done using methods similar to those used for supply side planning. The reliability criteria values previously used for supply side planning may not be economically justified when integrated resource planning is used. Utilities may have to revise and adopt new, and perhaps lower supply reliability criteria for integrated resource planning. More complex reliability criteria, such as energy related indices, which take into account the magnitude, frequency and duration of the expected interruptions are better adapted than the simpler capacity-based reliability criteria such as loss of load expectation. 7 refs., 5 figs., 10 tabs

  20. Greenland and Natural Resources

    DEFF Research Database (Denmark)

    Lyck, Lise

    Greenland policy can delay and maybe change the future of the forecasted development of the use of natural resources. This book is relevant for anyone interested in Greenland in general and the development of Greenland both politically and economically and in relation natural resources....