WorldWideScience

Sample records for as low as reasonably achievable

  1. Reactor emergency preparedness: lifesaving or as low as reasonable achievable

    International Nuclear Information System (INIS)

    An emergency is defined as an unforseen combination of circumstances or the resultant state that calls for immediate action. Although not explicitly indicated, the implication is that the action is intended to protect life, limb and or property from extreme peril. For the most part, the kind and extent of the emergency planning required under current regulations of the USNRC do not appear to be so much related to emergencies (within the above definition) as they do toward the reduction of the off-site radiation doses from uncontrolled releases during reactor accident conditions to as low as reasonably achievable levels. Not only do the latter appear to be of questionable cost-effectiveness, but in their extent and complexity beyond normal disaster planning they may in fact be counter productive to optimum public safety

  2. Reactor emergency preparedness: lifesaving or as low as reasonable achievable

    Energy Technology Data Exchange (ETDEWEB)

    Hull, A.P.

    1981-01-01

    An emergency is defined as an unforseen combination of circumstances or the resultant state that calls for immediate action. Although not explicitly indicated, the implication is that the action is intended to protect life, limb and or property from extreme peril. For the most part, the kind and extent of the emergency planning required under current regulations of the USNRC do not appear to be so much related to emergencies (within the above definition) as they do toward the reduction of the off-site radiation doses from uncontrolled releases during reactor accident conditions to as low as reasonably achievable levels. Not only do the latter appear to be of questionable cost-effectiveness, but in their extent and complexity beyond normal disaster planning they may in fact be counter productive to optimum public safety.

  3. Pacific Northwest Laboratory plan to maintain radiation exposure as low as reasonably achievable (ALARA)

    International Nuclear Information System (INIS)

    This document describes the radiation safety program at the Pacific Northwest Laboratory (PNL). The practices and administrative policies of this program support the principles of ALARA (to maintain radiation exposure as low as reasonably achievable). This document also describes a program to establish safety goals at PNL to help ensure that operations are conducted according to ALARA principles

  4. As low as reasonably achievable (ALARA): is it appropriate for low level exposures?

    International Nuclear Information System (INIS)

    Through various researches and investigations it has been established that high doses of ionizing radiation are harmful to health and there is a linear relationship between dose and the effect. There is substantial controversy regarding the biological and health effects of low doses of ionizing radiation in humans and the biota, in vitro and in vivo despite the large amount of work carried out (both laboratory and epidemiological). By low-level exposure, we mean the exposure to radiation levels comparable to those encountered in the natural environment (ambient radiation level). The proponents of the ALARA policy are the believers of LNT hypothesis adopted by major scientific, official and governmental organizations such as ICRP, NCRP, the NAS-NRC etc. for risk assessment, according to which exposure to any amount of radiation, no matter howsoever small is potentially harmful. The idea that the dose to radiation worker should be As Low As Reasonably Achievable (ALARA) is only appropriate if small doses have a risk. Current radiation risk estimates, drawn by linear extrapolation, from high dose and dose rate of radiation to zero dose, clearly ignore the effects of the repair of DNA- the target of radiation damage. If the hormetic effect is added to the effect predicted by the LNT hypothesis, the resultant effect will be somewhat different from that predicted by the LNT hypothesis alone. Excellent human data show that a moderate increase in background radiation decreases the risk of cancer and significantly increases longevity. There are strong arguments, both experimental and epidemiological, which support the radiation hormesis (beneficial effects of low-level ionizing radiation). In the present paper, we propose to highlight the results of a comprehensive study of the available literature, data and reports of various radiation exposure and protection studies carried out in India and abroad. In conclusion, we find that the radiation hormesis contradicts the

  5. Licensee programs for maintaining occupational exposure to radiation as low as is reasonably achievable

    International Nuclear Information System (INIS)

    This report defines the concept of maintaining occupational exposures to radiation as low as is reasonably achievable (ALARA) and describes the elements necessary for specific licensees to implement, operate, and evaluate an effective ALARA program. Examples of cost-effectiveness analysis and optimization are provided. The rationale for providing more detailed guidance to specific licensees stems from the current recommendations provided by the International Commission on Radiological Protection, as well as from the increased regulatory emphasis on maintaining occupational exposures ALARA. The objective of this work is to provide the Nuclear Regulatory Commission with a basis for updating Regulatory Guide 8.10

  6. Principles and practices for keeping occupational radiation exposures at medical institutions as low as reasonably achievable

    International Nuclear Information System (INIS)

    Some of the major considerations in establishing management policies, staff, facilities and equipment, and operational procedures to promote radiation safety in medical or hospital care programs using radioactive materials licensed by the U.S. Nuclear Regulatory Commission (NRC) are presented. It is a compendium of good practices for establishing adequate radiation safety programs in medical institutions. The information presented is intended to aid the NRC licensee in fulfilling the philosophy of maintaining radiation exposures of employees, patients, visitors, and the public as low as reasonably achievable (ALARA). Each subsection of this report is designed to include the major radiation safety considerations of interest to the specific type of activity

  7. Principles and practices for keeping occupational radiation exposures at medical institutions as low as reasonably achievable

    International Nuclear Information System (INIS)

    This report is a companion document to Regulatory Guide 8.18, Information Relevant to Ensuring that Occupational Radiation Exposures at Medical Institutions Will Be As Low As Reasonably Achievable. Both documents have now been revised to incorporate many good suggestions received after the original documents were published for comment. This report is a compendium of good practices and helpful information derived from the experience of the radiological and health physics professions and is not be construed in any way as additional regulatory requirements of the Nuclear Regulatory Commission. The information presented, including comprehensive checklists of facilities, equipment, and procedures that should be considered for working with NRC-licensed materials in all types of hospital activities, is intended to aid the NRC licensee in fulfilling the philosophy of maintaining radiation exposures of employees, patients, visitors, and the public as low as reasonably achievable (ALARA). Each subsection of this report is designed to include the major radiation safety considerations pertaining to the respective hospital function. Thus, the busy health professional will neeed to read only a few pages of this document at any one time to obtain the information needed

  8. Methodology for making environmental as low as reasonably achievable (ALARA) determinations

    International Nuclear Information System (INIS)

    An overall evaluation concept for use in making differential cost-benefit analyses in environmental as low as reasonably achievable (ALARA) determinations is being implemented by Rockwell Hanford Operations. This evaluation includes consideration of seven categories: (1) capital costs; (2) operating costs; (3) state of the art; (4) safety; (5) accident or upset consequences; (6) reliability, operability, and maintainability; and (7) decommissionability. Appropriate weighting factors for each of these categories are under development so that ALARA determinations can be made by comparing scores of alternative proposals for facility design, operations, and upgrade. This method of evaluation circumvents the traditional basis of a stated monetary sum per person-rem of dose commitment. This alternative was generated by advice from legal counsel who advised against formally pursuing this avenue of approach to ALARA for environmental and occupational dose commitments

  9. Guide to reducing radiation exposure to as low as reasonably achievable (ALARA)

    International Nuclear Information System (INIS)

    This document is designed to provide DOE contractor personnel with general guidance regarding programs and techniques to reduce radiation exposures to as low as reasonably achievable (ALARA). Thus it is directed towards a broad audience, and should have special relevance and interest for operating management as well as radiation protection personnel. It is well recognized that each contractor has needs specific and critical to its radiation protection program. Hence no single set of specific and detailed criteria can be set down as a prescription for achieving the ALARA goal. Rather, general guidance in the form of broad principles is given in order to acquaint management with ALARA needs and concepts. The purpose is to encourage maximum management support of the technical personnel responsible for carrying out day-to-day radiation protection activities. Although primarily written for management, this document also contains technical guidance of potential value to those directly involved in radiation protection activities. Again it should be stressed that what is provided is guidance, and is therefore not mandatory

  10. Guide to reducing radiation exposure to as low as reasonably achievable (ALARA)

    Energy Technology Data Exchange (ETDEWEB)

    Kathren, R.L.

    1980-04-01

    This document is designed to provide DOE contractor personnel with general guidance regarding programs and techniques to reduce radiation exposures to as low as reasonably achievable (ALARA). Thus it is directed towards a broad audience, and should have special relevance and interest for operating management as well as radiation protection personnel. It is well recognized that each contractor has needs specific and critical to its radiation protection program. Hence no single set of specific and detailed criteria can be set down as a prescription for achieving the ALARA goal. Rather, general guidance in the form of broad principles is given in order to acquaint management with ALARA needs and concepts. The purpose is to encourage maximum management support of the technical personnel responsible for carrying out day-to-day radiation protection activities. Although primarily written for management, this document also contains technical guidance of potential value to those directly involved in radiation protection activities. Again it should be stressed that what is provided is guidance, and is therefore not mandatory.

  11. Design features of the cold vacuum drying facility to keep worker doses as low as reasonably achievable

    Energy Technology Data Exchange (ETDEWEB)

    NELSON, J.V.

    1999-06-24

    This report describes the design features and steps taken to ensure that the Cold Vacuum Drying Facility satisfies regulatory requirements that personnel doses be kept as low as reasonably achievable (ALARA). This report also documents an analysis of worker doses and demonstrates that the ALARA goal of limiting individual doses to 500 mrem per year can be met.

  12. Guidelines on how to meet the requirement to keep all exposures as low as reasonably achievable. Regulatory guide

    International Nuclear Information System (INIS)

    The purpose of Regulatory Guide G-129 (E) is to provide Atomic Energy Control Board (AECB) licensees with guidelines on how to meet the forthcoming AECB regulatory requirement to keep doses received by workers and members of the public As Low As Reasonably Achievable (ALARA), social and economic factors taken into account. it is realized that the scope for realistic dose reductions will vary depending on the nature of the licensed activity. Therefore, criteria are given in section D for determining if doses can be deemed to be as low as reasonably achievable without further evaluation. The elements that the AECB considers to be essential in the approach to ALARA are described in section E and are summarized as follows: a demonstrated management commitment to the ALARA principle; the implementation of ALARA through a licensee's organization and management, provision of resources, training, establishment of action levels, documentation and other measures; and regular operational reviews. The above elements will be the focus of any AECB assessment to verify compliance with the requirement to keep radiation exposures as low as reasonably achievable. (author)

  13. Health physics manual of good practices for reducing radiation exposure to levels that are as low as reasonably achievable (ALARA)

    International Nuclear Information System (INIS)

    A primary objective of the US Department of Energy (DOE) health physics and radiation protection program has been to limit radiation exposures to those levels that are as low as reasonably achievable (ALARA). As a result, the ALARA concept developed into a program and a set of operational principles to ensure that the objective was consistently met. Implementation of these principles required that a guide be produced. The original ALARA guide was issued by DOE in 1980 to promote improved understanding of ALARA concepts within the DOE community and to assist those responsible for operational ALARA activities in attaining their goals. Since 1980, additional guidance has been published by national and international organizations to provide further definition and clarification to ALARA concepts. As basic ALARA experience increased, the value and role of the original guide prompted the DOE Office of Nuclear Safety (ONS) to support a current revision. The revised manual of good practices includes six sections: 1.0 Introduction, 2.0 Administration, 3.0 Optimization, 4.0 Setting and Evaluating ALARA Goals, 5.0 Radiological Design, and 6.0 Conduct of Operations. The manual is directed primarily to contractor and DOE staff who are responsible for conduct and overview of radiation protection and ALARA programs at DOE facilities. The intent is to provide sufficient guidance such that the manual, if followed, will ensure that radiation exposures are maintained as low as reasonably achievable and will establish the basis for a formally structured and auditable program. 118 refs., 16 figs., 3 tabs

  14. Health physics manual of good practices for reducing radiation exposure to levels that are as low as reasonably achievable (ALARA)

    Energy Technology Data Exchange (ETDEWEB)

    Herrington, W.N.; Higby, D.P.; Kathren,., R.L.; Merwin, S.E.; Stoetzel, G.A.

    1988-06-01

    A primary objective of the US Department of Energy (DOE) health physics and radiation protection program has been to limit radiation exposures to those levels that are as low as reasonably achievable (ALARA). As a result, the ALARA concept developed into a program and a set of operational principles to ensure that the objective was consistently met. Implementation of these principles required that a guide be produced. The original ALARA guide was issued by DOE in 1980 to promote improved understanding of ALARA concepts within the DOE community and to assist those responsible for operational ALARA activities in attaining their goals. Since 1980, additional guidance has been published by national and international organizations to provide further definition and clarification to ALARA concepts. As basic ALARA experience increased, the value and role of the original guide prompted the DOE Office of Nuclear Safety (ONS) to support a current revision. The revised manual of good practices includes six sections: 1.0 Introduction, 2.0 Administration, 3.0 Optimization, 4.0 Setting and Evaluating ALARA Goals, 5.0 Radiological Design, and 6.0 Conduct of Operations. The manual is directed primarily to contractor and DOE staff who are responsible for conduct and overview of radiation protection and ALARA programs at DOE facilities. The intent is to provide sufficient guidance such that the manual, if followed, will ensure that radiation exposures are maintained as low as reasonably achievable and will establish the basis for a formally structured and auditable program. 118 refs., 16 figs., 3 tabs.

  15. Computer Security: SAHARA - Security As High As Reasonably Achievable

    CERN Multimedia

    Stefan Lueders, Computer Security Team

    2015-01-01

    History has shown us time and again that our computer systems, computing services and control systems have digital security deficiencies. Too often we deploy stop-gap solutions and improvised hacks, or we just accept that it is too late to change things.    In my opinion, this blatantly contradicts the professionalism we show in our daily work. Other priorities and time pressure force us to ignore security or to consider it too late to do anything… but we can do better. Just look at how “safety” is dealt with at CERN! “ALARA” (As Low As Reasonably Achievable) is the objective set by the CERN HSE group when considering our individual radiological exposure. Following this paradigm, and shifting it from CERN safety to CERN computer security, would give us “SAHARA”: “Security As High As Reasonably Achievable”. In other words, all possible computer security measures must be applied, so long as ...

  16. The ALARA (as low as reasonably achievable) concept in pediatric interventional and fluoroscopic imaging: striving to keep radiation doses as low as possible during fluoroscopy of pediatric patients - a white paper executive summary

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, Keith J. [Children' s Hospital, Department of Radiology, Boston, MA (United States); Kaste, Sue C. [St. Jude Children' s Research Hospital, Division of Diagnostic Imaging, Memphis, TN (United States)

    2006-09-15

    ALARA represents a practice mandate adhering to the principle of keeping radiation doses to patients and personnel As Low As Reasonably Achievable. This concept is strongly endorsed by the Society for Pediatric Radiology, particularly in the use of procedures and modalities involving higher radiation doses such as CT and fluoroscopic examinations of pediatric patients. There is no doubt that medical imaging, which has undergone tremendous technological advances in recent decades, is integral to patient care. However, these technological advances generally precede the knowledge of end-users concerning the optimal use and correct operation of the resulting imaging equipment, and such knowledge is essential to minimizing potential risks to the patients. Current imaging methods must be optimized for radiation dose reduction in pediatric patients who might be as much as ten times more radiosensitive than adults. Unlike straightforward radiographic examinations, radiation dose to the patient during fluoroscopy is dependent on the operator's training, experience with the fluoroscope, and efficiency in completing a diagnostic study. The range of pediatric radiation doses from fluoroscopy is wide because this examination is performed not only by pediatric radiologists but also by general radiologists who occasionally care for children, interventional cardiologists, gastroenterologists, urologists and others. Thus, a venue where multidisciplinary interaction by this variety of operators can occur serves to improve pediatric patient care.

  17. The ALARA (as low as reasonably achievable) concept in pediatric interventional and fluoroscopic imaging: striving to keep radiation doses as low as possible during fluoroscopy of pediatric patients - a white paper executive summary

    International Nuclear Information System (INIS)

    ALARA represents a practice mandate adhering to the principle of keeping radiation doses to patients and personnel As Low As Reasonably Achievable. This concept is strongly endorsed by the Society for Pediatric Radiology, particularly in the use of procedures and modalities involving higher radiation doses such as CT and fluoroscopic examinations of pediatric patients. There is no doubt that medical imaging, which has undergone tremendous technological advances in recent decades, is integral to patient care. However, these technological advances generally precede the knowledge of end-users concerning the optimal use and correct operation of the resulting imaging equipment, and such knowledge is essential to minimizing potential risks to the patients. Current imaging methods must be optimized for radiation dose reduction in pediatric patients who might be as much as ten times more radiosensitive than adults. Unlike straightforward radiographic examinations, radiation dose to the patient during fluoroscopy is dependent on the operator's training, experience with the fluoroscope, and efficiency in completing a diagnostic study. The range of pediatric radiation doses from fluoroscopy is wide because this examination is performed not only by pediatric radiologists but also by general radiologists who occasionally care for children, interventional cardiologists, gastroenterologists, urologists and others. Thus, a venue where multidisciplinary interaction by this variety of operators can occur serves to improve pediatric patient care

  18. Safety as high and as harmonized as reasonably achievable: Nuclear regulators facing globalization

    International Nuclear Information System (INIS)

    The use of nuclear energy and ionizing radiation is being extensively scrutinized once again in light of the present debate on its role in sustainable development and on global security problems. Nuclear power is an important feature of today's energy supply. Commercial nuclear generation is a mature, established technology, having accumulated over 40 years of successful operation. Yet nuclear power raises passions as do few other energy issues. Within countries and among them, both support and opposition are strong. Loyola de Palacio, the European Union Commissioner responsible for energy and transport, summed up the dilemma very succinctly: Either we shut down the nuclear sector and give up on Kyoto, or we do not shut down the nuclear sector and we respect Kyoto. It is as simple as that: sometimes you have to put it crudely so that people understand. What is the role of nuclear regulators in this environment? The primary objective of government intervention into nuclear business is to allow humankind to maximize the benefits and minimize the risks emanating from nuclear sciences and their applications. Because both the nuclear power industry and the societal context within which it is regulated are dynamic, regulators must continuously assess their approaches to regulation to best achieve their regulatory mandate. This includes adjusting the boundaries of activity between the plant and the regulator. That is, working out the practical approaches that allow the power reactor operator/owner to achieve and maintain safety while allowing the regulatory body to assure itself and the public that appropriate levels of safety are achieved and maintained

  19. ALARA [as low as reasonably achievable] engineering at Department of Energy facilities: Bibliography of selected readings in radiation protection and ALARA

    International Nuclear Information System (INIS)

    This report is the first in the series of bibliographies supporting the efforts at the Brookhaven National Laboratory ALARA Center on dose reduction at DOE facilities. Abstracts for this bibliography were selected from proceedings of technical meetings, journals, research reports, and searches of the DOE Energy Data Base. The abstracts included in this report relate to operational health physics as well as other subjects which have a bearing on dose reduction. Facilities covered include: radioactive waste, uranium enrichment, fabrication, unirradiated fissile materials storage, irradiated fissile material storage, reprocessing, decommissioning, recovery, hot laboratories, tritium production, reactors (research, test and production but not power reactors), and accelerators. We have also included material in improved design, materials selection, planning, and other topics which are related to dose-reduction efforts. The report contains 68 abstracts as well as subject and author indices

  20. Reasoning as simulation.

    Science.gov (United States)

    Cassimatis, Nicholas L; Murugesan, Arthi; Bignoli, Perrin G

    2009-11-01

    The theory that human cognition proceeds through mental simulations, if true, would provide a parsimonious explanation of how the mechanisms of reasoning and problem solving integrate with and develop from mechanisms underlying forms of cognition that occur earlier in evolution and development. However, questions remain about whether simulation mechanisms are powerful enough to exhibit human-level reasoning and inference. In order to investigate this issue, we show that it is possible to characterize some of the most powerful modern artificial intelligence algorithms for logical and probabilistic inference as methods of simulating alternate states of the world. We show that a set of specific human perceptual mechanisms, even if not implemented using mechanisms described in artificial intelligence, can nevertheless perform the same operations as those algorithms. Although this result does not demonstrate that simulation theory is true, it does show that whatever mechanisms underlie perception have at least as much power to explain non-perceptual human reasoning and problem solving as some of the most powerful known algorithms. PMID:19277746

  1. Working Memory and Dynamic Measures of Analogical Reasoning as Predictors of Children's Math and Reading Achievement

    Science.gov (United States)

    Stevenson, Claire E.; Bergwerff, Catharina E.; Heiser, Willem J.; Resing, Wilma C. M.

    2014-01-01

    Working memory and inductive reasoning ability each appear related to children's achievement in math and reading. Dynamic measures of reasoning, based on an assessment procedure including feedback, may provide additional predictive value. The aim of this study was to investigate whether working memory and dynamic measures of analogical…

  2. Quality control as a way to find out doses as low as reasonably practicable in mammography systems

    International Nuclear Information System (INIS)

    The breast cancer is the most common neoplasm amongst women. Mammography is an essential tool for diagnosis and early detection of this disease. In order to guarantee the effectiveness of the diagnosis taking into account the patient radiation safety, it is mandatory to perform the quality control tests of the mammographic equipment. The main objective of this work has been to evaluate the relationship between the image quality and the total performance of the medical equipment. Primary data were collected from several radiological facilities during the quality control inspections performed by the local regulatory authorities of the Brazilian health, the National Commission of Nuclear Energy and the Brazilian College of Radiology. The main important functioning parameters were evaluated as well as the image quality using the simulator 'phantom mama'. In spite of the fact that high quality images could suggest delivering large radiation doses to patients it has been demonstrated that it is possible to acquire images with a good quality for clinical diagnosis without delivering high doses if the system is working properly. It has been concluded that following an optimized quality control program could avoid the complex dosimetric studies to guarantee good images quality. (author)

  3. Clinical reasoning as social deliberation

    DEFF Research Database (Denmark)

    2014-01-01

    In this paper I will challenge the individualistic model of clinical reasoning. I will argue that sometimes clinical practice is rather machine-like, and information is called to mind and weighed, but the clinician is not just calculating how to use particular means to reach fixed ends. Often the...

  4. Emotional Intelligence as a Predictor of Leadership of Kuwaiti High and Low Achieving 11th Graders

    Science.gov (United States)

    Alnabhan, Mousa

    2010-01-01

    The current study examined the association between emotional intelligence (EI) and the Leadership components (L) of high school students in the state of Kuwait. The possibility of predicting each leadership component via emotional intelligence components was investigated for high and low achievers. A sample of 11th grade students from Kuwaiti…

  5. Abstract spatial reasoning as an autistic strength.

    Science.gov (United States)

    Stevenson, Jennifer L; Gernsbacher, Morton Ann

    2013-01-01

    Autistic individuals typically excel on spatial tests that measure abstract reasoning, such as the Block Design subtest on intelligence test batteries and the Raven's Progressive Matrices nonverbal test of intelligence. Such well-replicated findings suggest that abstract spatial processing is a relative and perhaps absolute strength of autistic individuals. However, previous studies have not systematically varied reasoning level--concrete vs. abstract--and test domain--spatial vs. numerical vs. verbal, which the current study did. Autistic participants (N = 72) and non-autistic participants (N = 72) completed a battery of 12 tests that varied by reasoning level (concrete vs. abstract) and domain (spatial vs. numerical vs. verbal). Autistic participants outperformed non-autistic participants on abstract spatial tests. Non-autistic participants did not outperform autistic participants on any of the three domains (spatial, numerical, and verbal) or at either of the two reasoning levels (concrete and abstract), suggesting similarity in abilities between autistic and non-autistic individuals, with abstract spatial reasoning as an autistic strength. PMID:23533615

  6. Team Reasoning as a Guide to Coordination

    OpenAIRE

    Lahno, Amrei Marie; Lahno, Bernd

    2014-01-01

    A particular problem of traditional Rational Choice Theory is that it cannot explain equilibrium selection in simple coordination games. In this paper we analyze and discuss the solution concept for common coordination problems as incorporated in the theory of Team Reasoning (TR). Special consideration is given to TR’s concept of opportunistic choice and to the resulting restrictions in using private information. We report results from a laboratory experiment in which teams were given a chanc...

  7. The Complexities of Realizing Community: Assistant Principals as Community Leaders in Persistently Low-Achieving Schools

    Science.gov (United States)

    Bukoski, Beth E.; Lewis, Tiffanie C.; Carpenter, Bradley W.; Berry, Matthew S.; Sanders, Kimberly N.

    2015-01-01

    Meaningful community involvement has been linked to enhancements in student achievement and quality of educational experiences. Assistant principals are positioned to build effective partnerships yet remain understudied in the leadership preparation field. This qualitative study investigated how assistant principals (N = 9) serving historically…

  8. Low availability of carnitine precursors as a possible reason for the diminished plasma carnitine concentrations in pregnant women

    OpenAIRE

    Seliger Gregor; Hanisch Nicole; Ringseis Robert; Eder Klaus

    2010-01-01

    Abstract Background It has been shown that plasma carnitine concentrations decrease markedly during gestation. A recent study performed with a low number of subjects suggested that this effect could be due to a low iron status which leads to an impairment of carnitine synthesis. The present study aimed to confirm this finding in a greater number of subjects. It was moreover intended to find out whether low carnitine concentrations during pregnancy could be due to a reduced availability of pre...

  9. [Shared governance and reasonableness as ethical contributions to health policy].

    Science.gov (United States)

    Costa-Alcaraz, Ana M; Calvo-Rigual, Fernando; Siurana-Aparisi, Juan Carlos

    2013-01-01

    Health is one of the fundamental human rights. Recognizing it as a right means that the State has an obligation to ensure a minimum level of opportunities is maintained, and to restore it when lost. This minimum level may not be covered in periods of economic crisis, such as the one we are currently experiencing.Managed care, focused on economic questions, emerged after the crisis of 1973 in order to help make clinical decisions based on economic factors. In practice, the result of managed care was to turn economic cost control into an end in itself while forgetting about equity; something for which it has been challenged from an ethical perspective. Since then, many authors have attempted to reconcile efficiency and equity in health management, but the debate remains open.In this article, and basing our approach on the theories of P. Ruger and Norman Daniels, we argue that shared health governance and accountability for reasonableness can offer significant ethical contributions in the process of achieving an efficient and fair health system. In the model we propose, citizens, professionals and health institutions all play an active role in capacity building in the field of health. These capacities are related to healthy lifestyles, accessible and transparent information, the promotion of self-care, the acquisition of knowledge, skills and appropriate attitudes, leadership based on values and co-responsibility to achieve set goals in a reasonable way. If we develop these capacities, we will have used the current economic crisis as an opportunity for improving ethical practice in the field of health. PMID:23775103

  10. Teachers' Spatial Literacy as Visualization, Reasoning, and Communication

    Science.gov (United States)

    Moore-Russo, Deborah; Viglietti, Janine M.; Chiu, Ming Ming; Bateman, Susan M.

    2013-01-01

    This paper conceptualizes spatial literacy as consisting of three overlapping domains: visualization, reasoning, and communication. By considering these domains, this study explores different aspects of spatial literacy to better understand how a group of mathematics teachers reasoned about spatial tasks. Seventy-five preservice and inservice…

  11. Using Analogy to Improve Abstract Conditional Reasoning in Adolescents: Not as Easy as It Looks

    Science.gov (United States)

    Markovits, Henry; Doyon, Celine

    2011-01-01

    Abstract reasoning refers to the ability to reason logically with premises that do not allow reference to knowledge about the real world. This form of reasoning is complex and difficult, and at the same time, it is critical for understanding science and mathematics. Two studies examined the use of analogy as a method to bridge reasoning with…

  12. Deductive way of reasoning about the internet AS level topology

    Institute of Scientific and Technical Information of China (English)

    D´avid Szab´o; Attila K˝or¨osi; J´ozsef B´ır´o; Andr´as Guly´as

    2015-01-01

    Our current understanding about the AS level topology of the Internet is based on measurements and inductive-type models which set up rules describing the behavior (node and edge dynamics) of the individual ASes and generalize the consequences of these individual actions for the complete AS ecosystem using induction. In this paper we suggest a third, deductive approach in which we have premises for the whole AS system and the consequences of these premises are determined through deductive reasoning. We show that such a deductive approach can give complementary insights into the topological properties of the AS graph. While inductive models can mostly reflect high level statistics (e.g., degree distribution, clustering, diameter), deductive reasoning can identify omnipresent subgraphs and peering likelihood. We also propose a model, called YEAS, incorporating our deductive analytical findings that produces topologies contain both traditional and novel metrics for the AS level Internet.

  13. Gender as a predictor for academic achievement

    Directory of Open Access Journals (Sweden)

    Endang Lestari

    2012-07-01

    penting profesionalisme, keberhasilan akademik mahasiswa   Abstract   Background: Professionalism is central to maintaining public’s trust in medical profession. Building professionalism during their study time in medical education is possible method to equip students with core attributes of professional behavior of doctor. However, the professional practice might influence not only their future job, but also their recent performance as students. This study aimed to identify the correlation between students’ demographic factors and core attributes of professionalism related to good grade point average achievement. Methods: Fourth year students of Faculty of Medicine Universitas Islam Sultan Agung Islamic in Semarang Indonesia took part in this cross sectional study. The core attributes of professionalism were assessed using short inventory “Assessment of Medical Student Professionalism”, which was developed by some experts using Delphi method. The students’ grade point average (GPA data were collected from the Information Technology Unit of the faculty. Analysis data using Cox-regression with constant time. Results: A total amount of 207 (out of 240 students participated in this study. Our final model indicates that none of the core attributes professionalism which predicts good grade point average (GPA achievement. Female than male students had 35% increased to be good GPA achievement [adjusted relative risk (RRa = 1.35; 95% confidence interval (CI = 1.05-1.74]. Conclusion: Female but none of the core attribute of professionalism students was noted to increase academic grade point average. (Health Science Indones 2010; 1: 43 - 50

  14. Social science as a tool in developing scientific thinking skills in underserved, low-achieving urban students.

    Science.gov (United States)

    Jewett, Elizabeth; Kuhn, Deanna

    2016-03-01

    Engagement in purposeful problem solving involving social science content was sufficient to develop a key set of inquiry skills in low-performing middle school students from an academically and economically disadvantaged urban public school population, with this skill transferring to a more traditional written scientific thinking assessment instrument 3weeks later. Students only observing their peers' activity or not participating at all failed to show these gains. Implications are addressed with regard to the mastery of scientific thinking skills among academically disadvantaged students. Also addressed are the efficacy of problem-based learning and the limits of observational learning. PMID:26643851

  15. Reasons vs. Causes: Emergence as experienced by the human agent

    OpenAIRE

    Jorion, Paul J

    2007-01-01

    Because they are in constant interaction with each other, human beings are often agents within emergent collective processes. Although they are then acting as particles in a field-type phenomenon, their awareness of what they are part of entails that they hold views about why they’re acting the way they do, these, they call “reasons.” Should physicists dismiss such “reasons” as being illusory causes of events? “Reasons” are actually important explanatory factors of emergent phenomena...

  16. Deductive way of reasoning about the internet AS level topology

    Science.gov (United States)

    Dávid, Szabó; Attila, Kőrösi; József, Bíró; András, Gulyás

    2015-11-01

    Our current understanding about the AS level topology of the Internet is based on measurements and inductive-type models which set up rules describing the behavior (node and edge dynamics) of the individual ASes and generalize the consequences of these individual actions for the complete AS ecosystem using induction. In this paper we suggest a third, deductive approach in which we have premises for the whole AS system and the consequences of these premises are determined through deductive reasoning. We show that such a deductive approach can give complementary insights into the topological properties of the AS graph. While inductive models can mostly reflect high level statistics (e.g., degree distribution, clustering, diameter), deductive reasoning can identify omnipresent subgraphs and peering likelihood. We also propose a model, called YEAS, incorporating our deductive analytical findings that produces topologies contain both traditional and novel metrics for the AS level Internet. Project supported by Ericsson and partially supported by the Hungarian Scientific Research Fund (Grant No. OTKA 108947).

  17. Non-Verbal Reasoning Ability and Academic Achievement as Moderators of the Relation between Adverse Life Events and Emotional and Behavioural Problems in Early Adolescence: The Importance of Moderator and Outcome Specificity

    Science.gov (United States)

    Flouri, Eirini; Tzavidis, Nikos

    2011-01-01

    This study was carried out to model the functional form of the effect of contextual risk (number of adverse life events) on emotional and behavioural problems in early adolescence, and to test how intelligence and academic achievement compare as moderators of this effect. The effect of number of adverse life events on emotional and behavioural…

  18. Using optimal combination of teaching-learning methods (open book assignment and group tutorials) as revision exercises to improve learning outcome in low achievers in biochemistry.

    Science.gov (United States)

    Rajappa, Medha; Bobby, Zachariah; Nandeesha, H; Suryapriya, R; Ragul, Anithasri; Yuvaraj, B; Revathy, G; Priyadarssini, M

    2016-07-01

    Graduate medical students of India are taught Biochemistry by didactic lectures and they hardly get any opportunity to clarify their doubts and reinforce the concepts which they learn in these lectures. We used a combination of teaching-learning (T-L) methods (open book assignment followed by group tutorials) to study their efficacy in improving the learning outcome. About 143 graduate medical students were classified into low (75%: group 3, n = 46) achievers, based on their internal assessment marks. After the regular teaching module on the topics "Vitamins and Enzymology", all the students attempted an open book assignment without peer consultation. Then all the students participated in group tutorials. The effects on the groups were evaluated by pre and posttests at the end of each phase, with the same set of MCQs. Gain from group tutorials and overall gain was significantly higher in the low achievers, compared to other groups. High and medium achievers obtained more gain from open book assignment, than group tutorials. The overall gain was significantly higher than the gain obtained from open book assignment or group tutorials, in all three groups. All the three groups retained the gain even after 1 week of the exercise. Hence, optimal use of novel T-L methods (open book assignment followed by group tutorials) as revision exercises help in strengthening concepts in Biochemistry in this oft neglected group of low achievers in graduate medical education. © 2016 by The International Union of Biochemistry and Molecular Biology, 44(4):321-325, 2016. PMID:26891594

  19. Proportional reasoning as a key to numeracy across the curriculum

    DEFF Research Database (Denmark)

    Hilton, Annette; Hilton, Geoff

    2013-01-01

    -based learning materials and teaching resources to promote proportional reasoning across all curriculum areas in multiple year levels. These resources are now freely available for teachers beyond the project and the findings have been widely disseminated through journal publications and local and internatinal...... multiplicative structures. Research has highlighted time and again the difficulties that students and teachers experience in proportion and proportional related tasks. This deficit has also been identified in national and international tests, such as NAPLAN in Australia and PISA and TIMMS assessments...... project responded to these findings through an ongoing professional development program for middle school teachers. A design-based research approach was utilised in which over 120 teachers and school leaders from almost 30 schools participated in multiple workshops over the course of two years (eight half...

  20. Rock Pore Structure as Main Reason of Rock Deterioration

    Science.gov (United States)

    Ondrášik, Martin; Kopecký, Miloslav

    2014-03-01

    Crashed or dimensional rocks have been used as natural construction material, decoration stone or as material for artistic sculptures. Especially old historical towns not only in Slovakia have had experiences with use of stones for construction purposes for centuries. The whole buildings were made from dimensional stone, like sandstone, limestone or rhyolite. Pavements were made especially from basalt, andesite, rhyolite or granite. Also the most common modern construction material - concrete includes large amounts of crashed rock, especially limestone, dolostone and andesite. However, rock as any other material if exposed to exogenous processes starts to deteriorate. Especially mechanical weathering can be very intensive if rock with unsuitable rock properties is used. For long it had been believed that repeated freezing and thawing in relation to high absorption is the main reason of the rock deterioration. In Slovakia for many years the high water absorption was set as exclusion criterion for use of rocks and stones in building industry. Only after 1989 the absorption was accepted as merely informational rock property and not exclusion. The reason of the change was not the understanding of the relationship between the porosity and rock deterioration, but more or less good experiences with some high porous rocks used in constructions exposed to severe weather conditions and proving a lack of relationship between rock freeze-thaw resistivity and water absorption. Results of the recent worldwide research suggest that understanding a resistivity of rocks against deterioration is hidden not in the absorption but in the structure of rock pores in relation to thermodynamic properties of pore water and tensile strength of rocks and rock minerals. Also this article presents some results of research on rock deterioration and pore structure performed on 88 rock samples. The results divide the rocks tested into two groups - group N in which the pore water does not freeze

  1. Default logic as a formalism for understanding commonsense reasoning

    OpenAIRE

    Amati, Gianni; Carlucci Aiello, Luigia; Pirri, Fiora

    1996-01-01

    Commonsense reasoning is the reasoning of agents interacting with the real world. Non monotonic reasoning is a well developed research area gathering the logical formalisms that treat commonsense reasoning. One of the best known of such formalisms is Default logic. In this paper we discuss Default logic at both the proof-theoretic and semantics levels and show that Default logic provides a clear and formal framework to understand the logical nature of commonsense reasoning.

  2. Using Literature as a Vehicle to Explore Proportional Reasoning.

    Science.gov (United States)

    Thompson, Denisse R.; Austin, Richard A.; Beckmann, Charlene E.

    The development of proportional reasoning is a major focus of the middle grades curriculum. The challenge for educators is to find contexts that engage students and that facilitate the study of proportional reasoning. This chapter explores proportional thinking with students in grades 3-8 by using a number of books in which the underlying stories…

  3. Deductive Way of Reasoning about the Internet AS Level Topology

    OpenAIRE

    Szabó, Dávid; Kőrösi, Attila; Bíró, József; Gulyás, András

    2015-01-01

    Our current understanding about the AS level topology of the Internet is based on measurements and inductive-type models which set up rules describing the behavior (node and edge dynamics) of the individual ASes and generalize the consequences of these individual actions for the complete AS ecosystem using induction. In this paper we suggest a third, deductive approach in which we have premises for the whole AS system and the consequences of these premises are determined through deductive rea...

  4. Organizations As Overlapping Jurisdictions: Restoring Reason in Organizational Accounts.

    Science.gov (United States)

    Blau, Judith R.

    1996-01-01

    As Stern and Barley suggest, what is social about organizations is currently undertheorized, given the aspatial character of administration and financing, the reliance on external labor markets, and the global character of production and distribution. The "jurisdiction" concept provides a framework for considering organizations' social character…

  5. [Medicolegal considerations about rape as a reason to decriminalize abortion].

    Science.gov (United States)

    González-Wilhelm, Leonardo; Moreno, Leonardo; Carnevali, Raúl

    2016-06-01

    The Chilean senate is discussing a proposal to decriminalize abortion in 3 causals. One of these is when the pregnancy occurs as a result of a rape. To be legally able to perform the abortion in this circumstance, a health care team must confirm the occurrence of the facts constituting the offence. Regardless of the patient’s will, the accusation will be reported to the justice. In our view, in its current status the proposed rule does not consider certain medicolegal and procedural topics. Those flaws may determine in certain scenarios critical problems, such as: a) a wrongful conviction as a consequence of a false allegation of rape; (b) some pregnant due to a rape will not have access to the abortion procedure; (c) some accusations of rape will not be accredited nor criminally sanctioned. Employing a fictional case, we illustrate how those scenarios can actually be seen in practice. We also emphasize the difficulties and limitations that the health care team will encounter if the project is approved under the current conditions. Finally, we encourage the professional societies implicated in the theme to contribute in the legislatorial debate. Therefore, we give a set of proposals aimed to improve the bill before it may be enacted as a law. PMID:27598498

  6. Rhythm, Rhyme and Reason: Hip Hop Expressivity as Political Discourse

    OpenAIRE

    Nærland, Torgeir Uberg

    2014-01-01

    Using Norwegian hip hop as an example, this article argues that public sphere theory offers a fruitful theoretical framework in which to understand the political significance of music. Based on a musical and lyrical analysis of Lars Vaular's ‘Kem Skjøt Siv Jensen’ (Who Shot Siv Jensen) – a song that recently became the subject of extensive public political discourse in Norway – this article first highlights how the aesthetic language specific to hip hop music constitutes a form of political d...

  7. Linguistic Knowledge, Fluency and Meta-Cognitive Knowledge as Components of Reading Comprehension in Adolescent Low Achievers: Differences between Monolinguals and Bilinguals

    Science.gov (United States)

    Trapman, Mirjam; van Gelderen, Amos; van Steensel, Roel; van Schooten, Erik; Hulstijn, Jan

    2014-01-01

    In this study we investigate the role of linguistic knowledge, fluency and meta-cognitive knowledge in Dutch reading comprehension of monolingual and bilingual adolescent academic low achievers in the Netherlands. Results show that these components are substantially associated with reading comprehension. However, their role appears to be different…

  8. Can the Academic Achievement of Korean Students Be Portrayed as a Product of "Shadow Achievement"?

    Science.gov (United States)

    Kim, Hyunjin

    2015-01-01

    The purpose of this study was to investigate the effects of private tutoring expenditure on two types of Korean students' academic achievements as measured by standardized test achievement and by school performance achievement, applying 5-year data from Korean Educational Longitudinal Study (KELS). It was found that private tutoring…

  9. What Characterises High Achieving Students’ Mathematical Reasoning?

    OpenAIRE

    Haavold, Per Øystein

    2011-01-01

    This study investigates high achieving students’ mathematical reasoning when given an unfamiliar trigonometric equation. The findings indicate that the students’ way of thinking is strongly linked with imitative reasoning and only when they received some form of guidance, were they able to display flexible and creative mathematical reasoning.

  10. Social Intelligence and Academic Achievement as Predictors of Adolescent Popularity

    Science.gov (United States)

    Meijs, Noortje; Cillessen, Antonius H. N.; Scholte, Ron H. J.; Segers, Eliane; Spijkerman, Renske

    2010-01-01

    This study compared the effects of social intelligence and cognitive intelligence, as measured by academic achievement, on adolescent popularity in two school contexts. A distinction was made between sociometric popularity, a measure of acceptance, and perceived popularity, a measure of social dominance. Participants were 512, 14-15 year-old…

  11. Social Intelligence and Academic Achievement as Predictors of Adolescent Popularity

    NARCIS (Netherlands)

    Meijs, N.; Cillessen, A.H.N.; Scholte, R.H.J.; Segers, P.C.J.; Spijkerman, R.

    2010-01-01

    This study compared the effects of social intelligence and cognitive intelligence, as measured by academic achievement, on adolescent popularity in two school contexts. A distinction was made between sociometric popularity, a measure of acceptance, and perceived popularity, a measure of social domin

  12. Parenting Style as a Moderator for Students' Academic Achievement

    Science.gov (United States)

    Ishak, Zahari; Low, Suet Fin; Lau, Poh Li

    2012-01-01

    Parenting styles have always been a crucial factor in influencing all aspects of a person's development. The purpose of this study is to test the structural equation model of academic achievement among the students using parenting styles as a moderator. The sample comprised 493 students from eight schools. Parenting styles are determined using the…

  13. [Clinical reasoning supportive to a medical service provider as a tool for complaint management: a case study for pragmatic reasoning].

    Science.gov (United States)

    Wessels, B; Seger, W

    2014-12-01

    The process of "clinical reasoning" is exemplified as supportive to the complaint management of the Statutory Medical Health Advisory Board in Lower Saxony, Germany, within the operational division for long-term care insurance. A model case from real life illustrates in detail the hypothetical-deductive approach by Beusheusen and Klemme/Siegmann. Because of the potential area of conflicts between human concern in the case of a long-term care burden and legal requirements, the process was analysed in terms of a pragmatic reasoning. Human resources of the claimant and persons in charge at customer's service were demonstrated as well as political, statutory and institutional determining factors. Concluding self-perception validates the process in the context of evidence-based practice. PMID:25397910

  14. Social Intelligence and Academic Achievement as Predictors of Adolescent Popularity

    OpenAIRE

    Meijs, Noortje; Cillessen, Antonius H. N.; Scholte, Ron H. J.; Segers, Eliane; Spijkerman, Renske

    2008-01-01

    This study compared the effects of social intelligence and cognitive intelligence, as measured by academic achievement, on adolescent popularity in two school contexts. A distinction was made between sociometric popularity, a measure of acceptance, and perceived popularity, a measure of social dominance. Participants were 512, 14–15 year-old adolescents (56% girls, 44% boys) in vocational and college preparatory schools in Northwestern Europe. Perceived popularity was significantly related to...

  15. Developing a Cloze Procedure as a Reading Comprehension Achievement Test

    OpenAIRE

    I Ketut Seken

    2004-01-01

    The project was concerned with developing a cloze procedure as a reading comprehension achievement test. The subjects were students of the English Department of the Faculty of Letters, State University of Malang, who were halfway in the semester to complete Reading II course. The test was planned and constructed on the foundation of existing theory of cloze test construction. A review of theory concerning reading comprehension, testing reading comprehension, and cloze testing led to the const...

  16. Children's Reasoning as Collective Social Action through Problem Solving in Grade 2/3 Science Classrooms

    Science.gov (United States)

    Kim, Mijung

    2016-01-01

    Research on young children's reasoning show the complex relationships of knowledge, theories, and evidence in their decision-making and problem solving. Most of the research on children's reasoning skills has been done in individualized and formal research settings, not collective classroom environments where children often engage in learning and reasoning together to solve classroom problems. This study posits children's reasoning as a collective social activity that can occur in science classrooms. The study examined how children process their reasoning within the context of Grade 2/3 science classrooms and how the process of collectivity emerges from classroom interactions and dialogue between children as they attempt to solve their classroom problems. The study findings suggest that children's reasoning involves active evaluation of theories and evidence through collective problem solving, with consensus being developed through dialogical reasoning.

  17. Parenting Style as a Moderator for Students' Academic Achievement

    Science.gov (United States)

    Ishak, Zahari; Low, Suet Fin; Lau, Poh Li

    2012-08-01

    Parenting styles have always been a crucial factor in influencing all aspects of a person's development. The purpose of this study is to test the structural equation model of academic achievement among the students using parenting styles as a moderator. The sample comprised 493 students from eight schools. Parenting styles are determined using the Parental Authority Questionnaire (Buri in J Pers Assess 57:110-119, 1991). Academic achievement is measured based on the students' performance in the Lower Secondary Assessment. Data were analyzed using structural equation modelling. Results demonstrated that model of authoritative and model of authoritarian fit the data of this study well. Both authoritative and authoritarian parenting styles are the most common practice of the parents. Parenting styles have been found to be a moderator of this study. The results indicated that parenting styles moderated the effect of academic self-concept on academic achievement. The impact of academic self-concept on academic achievement is found to be greater for the authoritative than the authoritarian parenting style.

  18. Temperament-based learning styles as moderators of academic achievement.

    Science.gov (United States)

    Horton, C B; Oakland, T

    1997-01-01

    Considerable interest in applications of temperament theory has led to proposals of four temperament-related learning styles. The hypothesis that achievement is higher when instructional strategies utilize methods consistent with students' preferred learning styles was tested using 417 seventh graders, the majority of whom were from minority and low SES families. The hypothesis was not supported; instead, student achievement was significantly higher with instructional strategies designed to promote personalized learning. The need to extend temperament-based learning styles by considering additional qualities that are important to learning is discussed. PMID:9105497

  19. Personal and Pedagogical Interaction Factors as Determinants of Academic Achievement

    OpenAIRE

    Cardoso, Ana Paula; Ferreira, Manuela; Abrantes, José Luís; Seabra, Cláudia; Costa, Cesário

    2011-01-01

    This study intends to relate self-esteem, teacher-student interaction, student-student interaction and learning performance, and its direct and indirect relationships with academic achievement. Using a sample of about 2000 Portuguese high school students, a structural model reveals that low social self-esteem directly and negatively influences teacher-student interaction and studentstudent interaction and also learning performance. Teacher-student interaction directly and positively influence...

  20. Achieving reasonable conservatism in nuclear safety analyses

    International Nuclear Information System (INIS)

    In the absence of methods that explicitly account for uncertainties, seeking reasonable conservatism in nuclear safety analyses can quickly lead to extreme conservatism. The rate of divergence to extreme conservatism is often beyond the expert analysts’ intuitive feeling, but can be demonstrated mathematically. Too much conservatism in addressing the safety of nuclear facilities is not beneficial to society. Using certain properties of lognormal distributions for representation of input parameter uncertainties, example calculations for the risk and consequence of a fictitious facility accident scenario are presented. Results show that there are large differences between the calculated 95th percentiles and the extreme bounding values derived from using all input variables at their upper-bound estimates. Showing the relationship of the mean values to the key parameters of the output distributions, the paper concludes that the mean is the ideal candidate for representation of the value of an uncertain parameter. The mean value is proposed as the metric that is consistent with the concept of reasonable conservatism in nuclear safety analysis, because its value increases towards higher percentiles of the underlying positively skewed distribution with increasing levels of uncertainty. Insensitivity of the results to the actual underlying distributions is briefly demonstrated. - Highlights: • Multiple conservative assumptions can quickly diverge into extreme conservatism. • Mathematics and attractive properties provide basis for wide use of lognormal distribution. • Mean values are ideal candidates for representation of parameter uncertainties. • Mean values are proposed as reasonably conservative estimates of parameter uncertainties

  1. Sense of Belonging as a Predictor of Reasons for Living in Older Adults

    Science.gov (United States)

    Kissane, Melissa; McLaren, Suzanne

    2006-01-01

    In response to the high rate of suicide among aging people, this study investigated sense of belonging as a predictor of reasons for living in an aged sample. A community sample of 104 Australians aged 61 to 95 years completed The Reasons for Living Inventory and The Sense of Belonging Instrument. Results indicated that a higher sense of belonging…

  2. Critical Thinking: Ethical Reasoning as Essential to Fairminded Critical Thinking, Part III

    Science.gov (United States)

    Paul, Richard; Elder, Linda

    2010-01-01

    In the last two columns the authors introduced the idea of ethical reasoning and discussed its importance to education. They dealt with the problem of egocentric thinking as a barrier to ethical reasoning. And they focused on the importance of distinguishing ethics from other modes of thought with which it is often confused, namely social…

  3. Interactions between default mode and control networks as a function of increasing cognitive reasoning complexity.

    Science.gov (United States)

    Hearne, Luke; Cocchi, Luca; Zalesky, Andrew; Mattingley, Jason B

    2015-07-01

    Successful performance of challenging cognitive tasks depends on a consistent functional segregation of activity within the default-mode network, on the one hand, and control networks encompassing frontoparietal and cingulo-opercular areas on the other. Recent work, however, has suggested that in some cognitive control contexts nodes within the default-mode and control networks may actually cooperate to achieve optimal task performance. Here, we used functional magnetic resonance imaging to examine whether the ability to relate variables while solving a cognitive reasoning problem involves transient increases in connectivity between default-mode and control regions. Participants performed a modified version of the classic Wason selection task, in which the number of variables to be related is systematically varied across trials. As expected, areas within the default-mode network showed a parametric deactivation with increases in relational complexity, compared with neural activity in null trials. Critically, some of these areas also showed enhanced connectivity with task-positive control regions. Specifically, task-based connectivity between the striatum and the angular gyri, and between the thalamus and right temporal pole, increased as a function of relational complexity. These findings challenge the notion that functional segregation between regions within default-mode and control networks invariably support cognitive task performance, and reveal previously unknown roles for the striatum and thalamus in managing network dynamics during cognitive reasoning. PMID:25833189

  4. Public reason as a political ideal: John Rawls’s conception

    Directory of Open Access Journals (Sweden)

    Pavićević Đorđe

    2007-01-01

    Full Text Available The article dealt with Rawlsian idea of public reason as a convergence point of his conception of political liberalism. The idea of public reason is taken as a norm of political justification a as well as a political ideal. Major lines of criticism of the Rawls' conception are also discussed in the article. The conclusion is that is possible to defend major elements of Rawls' conception against criticism along Rawlsian lines of argumentation. The thesis advocated through the text is that it is significant legacy of Rawls' conception of public reason that it discloses limitations of political ideal of liberal democracy. It is argued that one important consequence is that liberalism has to disclaim its own moral superiority in order to make political ideal viable. The other is that any particular society has to find its moral bases in public reason of particular society, that is burdened with peculiar culture and history. .

  5. Exploring individual differences in deductive reasoning as a function of 'autistic'-like traits

    OpenAIRE

    Fugard, Andrew J. B.

    2009-01-01

    From a logical viewpoint, people must reason to as well as from interpretations in deductive reasoning tasks. There are two main interpretative stances (e.g., Stenning & van Lambalgen, 2004, 2005, 2008): credulous, the act of trying to infer the speaker's intended model; and sceptical, an adversarial strategy. A range of contextual factors in uence interpretation, but there are also differences between individuals across situations. Taking an individual differences approach,...

  6. Developing a Cloze Procedure as a Reading Comprehension Achievement Test

    Directory of Open Access Journals (Sweden)

    I Ketut Seken

    2004-01-01

    Full Text Available The project was concerned with developing a cloze procedure as a reading comprehension achievement test. The subjects were students of the English Department of the Faculty of Letters, State University of Malang, who were halfway in the semester to complete Reading II course. The test was planned and constructed on the foundation of existing theory of cloze test construction. A review of theory concerning reading comprehension, testing reading comprehension, and cloze testing led to the construction of the test, including the decision concerning how to score the test and to interpret the scores. Using a class of 28 students, the test was tried out a week after the mid-semester test was administered by the Reading II teacher. It was found that the test is sufficienty reliable on the basis of a reliability coefficient of .79 through split-half procedure and a coefficient value of .78 by K-R 20. The test also showed high inter-section correlation. The validity of the test was viewed in terms of face, content, and construct. The test scores correlate moderately with those obtained from the mid-semester test by the teacher. Some problems are discussed and a suggestion made with regard to a possible solution to these problems.

  7. Educating for Civic Engagement: Public Achievement as a Case Study

    Science.gov (United States)

    Costello, Bernadette Christine

    Over the last four decades there is evidence that citizens are less civically engaged, have less trust in each other and governmental institutions, and are less prepared to participate in deliberative and civic processes. This research studies the importance of acquiring deliberative and civic skills and behaviors as an integral part of civic engagement and developing educational and learning strategies to impart those skills and behaviors in an educational environment. This research uses a civic action program called Public Achievement (PA) as a case study to investigate if participating in a civic and deliberative focused program enables participants to continue to use the skills and behaviors learned in PA in non-PA activities. The research study was focused by a literature review of philosophical frameworks, educational history in the United States, and educational theory. The literature review and examples of learning civic skills and behaviors in secondary and higher educational institutions are examined to frame the analysis of PA. Based on the literature review and the design of PA, constructs and a survey instrument were developed to test the hypothesis that students who participate in PA will be more likely to exhibit civic skills and behaviors than students who did not participate in PA. The research was conducted with two schools in rural Missouri, two schools in Minneapolis, Minnesota, and two schools in St. Paul, Minnesota. The study results show that students who participated in PA were not more likely to exhibit civic skills and behaviors, and in many cases, non-PA students exhibited civic skills and behaviors more often. The findings revealed that there are programmatic, organizational, and societal barriers that may impede the effectiveness of PA. The findings suggest that implementation of civic engagement programs may be more effective when the effort is supported and reinforced by and across all parts of the organization, organizational

  8. Exploring mental-state reasoning as a social-cognitive mechanism for social loafing in children.

    Science.gov (United States)

    Thompson, Bruce; Thornton, Bill

    2007-04-01

    The authors explored mental-state reasoning ability among 72 preschoolers (ages 3-5 years) as a possible developmental mechanism for the well-known social loafing effect: diminished individual effort in a collaborative task. The authors expected that older children would outperform young children on standard mental-state reasoning tests and that they would display greater social loafing than younger children. In addition, we hypothesized that the ability to infer the mental states of others would be predictive of social loafing, but that the ability to reason about one's own knowledge would not. The authors gave children three standard false-belief tasks and participated in a within-subjects balloon inflation task that they performed both individually and as part of a group. Results indicated that 3-year-olds performed significantly below older preschoolers on mental-state reasoning tasks. Only 4- and 5-year-olds displayed diminished individual effort. Multiple regression analysis indicated that only the ability to reason about others' false beliefs accounted for a significant amount of variance in social loafing; age (in months) and own false-belief reasoning did not. The authors discussed theoretical and pedagogical implications. PMID:17601078

  9. Reconnection production-consumption: change to achieve food and nutritional security, as well as rural development.

    Directory of Open Access Journals (Sweden)

    Shirley Rodríguez-González

    2015-06-01

    Full Text Available The aim of this study was to analyze the importance of changing the conventional food system to achieve food and nutritional security, as well as rural development. This text was divided into three sections. In the first one, the conventional food system and its consequences were characterized, showing the need for a change that seeks the integration of social, environmental, and health dimensions. The second part addressed the interventions related to the food supply system made by the Government, which are fundamental to achieve food and nutrition security, as well as to promote development processes in rural areas. Finally, the experience of Brazil’s National School Feeding Programme was presented. That program links food produced by small producers with the National School Feeding Program, allowing the reconnection of production and consumers through institutional markets. That link created incentives for food and nutrition security of small farmers and, at the same time, improved the availability of higher- quality food for vulnerable populations and promotedeating patterns that allow the preservation of food culture.

  10. Extremely low density self-assembled InAs/GaAs quantum dots

    Institute of Scientific and Technical Information of China (English)

    Lin Li; Guojun Liu; Zhanguo Li; Mei Li; Xiaohua Wang

    2008-01-01

    The self-assembled InAs/GaAs quantum dots (QDs) with extremely low density of 8×106 cm-2 are achieved using higher growth temperature and lower InAs coverage by low-pressure metal-organic chemical vapour deposition (MOVCD). As a result of micro-photoluminescence (micro-PL), for extremely low density of 8×106 cm-2 InAs QDs in the micro-PL measurements at 10 K, only one emission peak has been achieved. It is believed that the InAs QDs have a good potential to realize single photon sources.

  11. Lean Production as Promoter of Thinkers to Achieve Companies' Agility

    Science.gov (United States)

    Alves, Anabela C.; Dinis-Carvalho, Jose; Sousa, Rui M.

    2012-01-01

    Purpose: This paper aims to explore the lean production paradigm as promoter of workers' creativity and thinking potential, and recognize this human potential as a fundamental asset for companies' growth and success, being a major factor to face the disturbing and unpredictable needs of current markets, providing companies with the necessary…

  12. Anomalies as a Catalyst for Middle School Students' Knowledge Construction and Scientific Reasoning during Science Inquiry.

    Science.gov (United States)

    Echevarria, Marissa

    2003-01-01

    Knowledge construction and scientific reasoning were examined during a unit in genetics, in which anomalies were used as a catalyst for student learning. Students used genetics simulation software to develop hypotheses and run tests of fruit fly crosses to develop mental models of simple dominance trait transmission. Instruction was intended to…

  13. School Size as a Factor in Elementary School Achievement.

    Science.gov (United States)

    Alspaugh, John W.; Gao, Rui

    The relationship between elementary school enrollment and fifth-grade achievement was explored using data from a large urban Missouri school district. The district's 39 elementary schools received uniform allocations of resources from the district and used the same instructional materials but varied considerably in K-5 enrollment, socioeconomic…

  14. The Importance of Motivation as a Predictor of School Achievement

    Science.gov (United States)

    Steinmayr, Ricarda; Spinath, Birgit

    2009-01-01

    The present study examined to which extent different motivational concepts contribute to the prediction of school achievement among adolescent students independently from intelligence. A sample of 342 11th and 12th graders (age M = 16.94; SD = .71) was investigated. Students gave self-reports on domain-specific values, ability self-perceptions,…

  15. Personality as a moderator of context effects on academic achievement

    NARCIS (Netherlands)

    Hendriks, A.A.J.; Kuyper, H.; Lubbers, M.J; Van der Werf, M.P.C.

    2011-01-01

    We investigated whether personality moderates group influence of classmates on academic achievement and whether these so-called context effects can be attributed to peer pressure. The sample consisted of 2498 students in their first year of Dutch secondary education. The data were analyzed by a two-

  16. Personality as a Moderator of Context Effects on Academic Achievement

    Science.gov (United States)

    Hendriks, A. A. Jolijn; Kuyper, Hans; Lubbers, Miranda J.; Van der Werf, Margaretha P. C.

    2011-01-01

    We investigated whether personality moderates group influence of classmates on academic achievement and whether these so-called context effects can be attributed to peer pressure. The sample consisted of 2498 students in their first year of Dutch secondary education. The data were analyzed by a two-level (students within classes) analysis,…

  17. Reasoning with Limited Resources: Active Logics Expressed as Labeled Deductive Systems

    OpenAIRE

    Asker, Mikael; Malec, Jacek

    2005-01-01

    Reasoning with limited computational resources (such as time or memory) is an important problem, in particular in knowledge-intensive embedded systems. Classical logic is usually considered inappropriate for this purpose as no guarantees regarding deadlines can be made. One of the moreinteresting approaches to address this problem is built around the concept of active logics. Although a step in the right direction, active logics are just a preliminary attempt towards finding an acceptable sol...

  18. Management accountants as business partners : An empirical analysis based on the theory of reasoned action

    OpenAIRE

    Wolf, Sebastian; Weißenberger, Barbara E.; Kabst, Rüdiger; Wehner, Sebastian

    2010-01-01

    Business practice and literature frequently advocate more business oriented roles for management accountants. The aim of this study is to examine reasons for management accountants to act as business partners and to analyze corresponding performance effects. More specifically, two research questions are investigated: (i) why do management accountants act as business partners, and (ii) are business oriented management accountants beneficial to organizations? To answer these research questio...

  19. Adults learning Finnish as a foreign language : role of support, emotions and reasons connected with learning

    OpenAIRE

    MacKenzie, Ashley

    2015-01-01

    The purpose of this research study was to examine adults learning Finnish as a foreign language while striving to understand the reasons behind their decisions to do so, the support that was individually offered to the participants, how they felt throughout the learning process, and whether or not they found themselves to be self-reliant learners, as per Knowles’ andragogy theory. This study set out to examine adult language learners participating in the language and integration program at Pa...

  20. Tele-centres as a way of achieving universal access

    DEFF Research Database (Denmark)

    Falch, Morten; Anyimadu, Amos

    2003-01-01

    The success of tele-centres in Ghana is discussed. The tele-centres offer a low cost opportunity to empower local communities in developed and developing countries to meet the challenges of the information society. The tele-centres can also contribute more directly to the supply of non-commercial...

  1. EMS as a basis of sustainable technological process achievement

    Directory of Open Access Journals (Sweden)

    R. Nowosielski

    2008-08-01

    Full Text Available Purpose: The paper presents main principles of environmental management systems ISO 14001 and EMAS. Thanks to EMS organizations can improve theirs activity especially through environmental modernization introducing to realized technological processes.Design/methodology/approach: Implementation of EMS provides organizations many benefits: increasing the efficient use of resources; waste reducing; demonstrate a good corporate image; building awareness of environmental concern among employees; gaining a better understanding of the environmental impacts of business activities and increase profit, improving environmental performance.Findings: In this article structure of ISO 14001 and EMAS were presented. Moreover the analysis and the modernization of the oil filter casings production process were showed.Research limitations/implications: Both ISO 14001 and EMAS II application all organizational units, especially industrial enterprises. The EMS requirements make possible technological processes continuous improvement especially in environment protection sphere.Practical implications: Formalized environmental management systems ISO 14001 and EMAS help enterprises in accommodation to the growing requirements of the environment protection prescriptions.Originality/value: The only one possibility of the environment protection is implementation and continuous improvement of EMS by every organization. It can be achieved through technological processes improvement.

  2. Problems of north-south international trade as the main reason of world trade organization difficulties

    OpenAIRE

    Jiří Fárek; Jaroslav Foltýn

    2007-01-01

    This article tries to summarize achievements of ten years anniversary of WTO (1995-2005) and the negotiations taking place at its summits from Seattle (1999) to Hongkong (2005). These achievements could be characterized at best as mediocre ones. WTO has been muddling through numerous disputes, the most important of which have been and still are agricultural subsidies of developed countries. Due to double standards and sometimes lack of transparency at least three summits (Seattle, Cancún and ...

  3. Of Pigs and Men: Understanding Students' Reasoning About the Use of Pigs as Donors for Xenotransplantation

    Science.gov (United States)

    Lindahl, Mats Gunnar

    2010-09-01

    Two important roles of education are to provide students with knowledge for their democratic participation in society and to provide knowledge for a future profession. In science education, students encounter values that may be in conflict with their worldview. Such conflicts may, for example, lead to constructive reflections as well as rejection of scientific knowledge and technology. Students’ ways of reasoning are important starting points for discussing problematic issues and may be crucial for constructive dialogues in the classroom. This study investigates students’ reasoning about conflicting values concerning the human-animal relationship exemplified by the use of genetically modified pigs as organ donors for xenotransplantation. Students’ reasoning is analyzed using Giddens’ concepts of disembedded and embedded practices in parallel with moral philosophical theories in a framework based on human-animal relationships. Thirteen students were interviewed and their stances categorized. Kantian deontological and classical utilitarian ethics were found within the patronage and the partnership models. These students appreciated expert knowledge but those using the partnership model could not accept xenotransplantation if pigs were to be killed. Students using care ethics did not appreciate expert knowledge since it threatened naturalness. The results suggest that stances against the use of scientific knowledge are more problematic than knowledge per se, and that conflicting stances have similarities that present opportunities for understanding and development of students’ argumentation skills for future participation in societal discourse on utilizing expert knowledge. Furthermore it is argued that science education could benefit from a higher awareness of the presence of different morals.

  4. Low activated materials as plasma facing component

    International Nuclear Information System (INIS)

    Low activated materials such as ferritic steel, vanadium alloy and SiC/SiC composite have to be developed for realization of a fusion demonstration reactor. Major issues concerning these low activated materials have been evaluation of neutron irradiation effects and feasibility as blanket materials. Since these are also in-vessel materials, issues of plasma material interactions have to be investigated. Ferritic steel, F82H, is well oxidized in the atmosphere. Thus, pre-baking is necessary before installation. The required baking temperature is higher than 900 K. Vanadium alloy, V-4Cr-4Ti, absorbs hydrogen well and hydrogen embrittlement takes place when the hydrogen concentration exceeds a critical level. In order to avoid hydrogen absorption, the formation of an oxide layer on the alloy was found to be very useful. In JFT-2M, the vanadium alloy was exposed to a deuterium discharge environment for 9 months. On the alloy surface, an oxide deposition layer with a thickness of 200 nm was formed. The deuterium concentration observed was very low, only 1.3 wppm. SiC/SiC composite may be employed as divertor plates in addition to its use as blanket material. Fuel hydrogen retention was very similar to that of graphite but the chemical erosion was negligibly small. (author)

  5. Relating Derived Relations as a Model of Analogical Reasoning: Reaction Times and Event-Related Potentials

    OpenAIRE

    Barnes-Holmes, Dermot; Regan, Donal; Barnes-Holmes, Yvonne; Commins, Sean; Walsh, Derek; Stewart, Ian; Smeets, Paul M; Whelan, Robert; Dymond, Simon

    2005-01-01

    The current study aimed to test a Relational Frame Theory (RFT) model of analogical reasoning based on the relating of derived same and derived difference relations. Experiment 1 recorded reaction time measures of similar–similar (e.g., “apple is to orange as dog is to cat”) versus different–different (e.g., “he is to his brother as chalk is to cheese”) derived relational responding, in both speed-contingent and speed-noncontingent conditions. Experiment 2 examined the event-related potential...

  6. Collaborative dominance: when doing unto others as you would have them do unto you is reasonable

    Directory of Open Access Journals (Sweden)

    Filipe Costa de Souza

    2013-12-01

    Full Text Available In this article, we analyze how reasonable it is to play according to some Nash equilibria if players have a preference for one of their opponents' strategies. To formalize our argument, we propose the concepts of collaborative dominance and collaborative equilibrium studying some of its properties. First, we prove that if the collaborative equilibrium exists, then it is always efficient, what can be seen as a focal property. Moreover, we argue that one reason that may lead players not to collaborate is that they can focus on security instead of efficiency properties, in which case they would prefer to play according to maximin strategies. This argument allows us to reduce the hall of reasonable equilibria for games where a collaborative equilibrium exists. Finally, we show that two-player zero-sum games do not have collaborative equilibrium, and that if they contain a strategy profile composed only of collaboratively dominated actions, then such profile is a Nash equilibrium of the game.

  7. Electronic books as low vision aids

    OpenAIRE

    Crossland, Michael; Macedo, António Filipe; Rubin, G S

    2010-01-01

    Every year, around 34 000 people in England and Wales are newly registered as sight impaired or severely sight impaired, the majority of whom have some residual vision.1 In order to read books, people with low vision will generally rely on large print books and supplementary optical2 or electronic3 magnifiers. Only about 1.5% of the approximately two million books currently in print are available in large print format.4 Recently, several electronic book readers have become commercially av...

  8. Semantic Matchmaking as Non-Monotonic Reasoning: A Description Logic Approach

    CERN Document Server

    Di Noia, T; Donini, F M; 10.1613/jair.2153

    2011-01-01

    Matchmaking arises when supply and demand meet in an electronic marketplace, or when agents search for a web service to perform some task, or even when recruiting agencies match curricula and job profiles. In such open environments, the objective of a matchmaking process is to discover best available offers to a given request. We address the problem of matchmaking from a knowledge representation perspective, with a formalization based on Description Logics. We devise Concept Abduction and Concept Contraction as non-monotonic inferences in Description Logics suitable for modeling matchmaking in a logical framework, and prove some related complexity results. We also present reasonable algorithms for semantic matchmaking based on the devised inferences, and prove that they obey to some commonsense properties. Finally, we report on the implementation of the proposed matchmaking framework, which has been used both as a mediator in e-marketplaces and for semantic web services discovery.

  9. ALARA in pediatric interventional and fluoroscopic imaging: striving to keep radiation doses as low as possible during fluoroscopy of pediatric patients--a white paper executive summary.

    Science.gov (United States)

    Strauss, Keith J; Kaste, Sue C

    2006-09-01

    Pediatric patients might be as much as 10 times more radiosensitive than adults. Thus, adherence to the principle of "As low as reasonably achievable" (ALARA) represents a practice mandate that minimizes ionizing radiation exposure while optimizing imaging results. This symposium is the third multidisciplinary program that focused on the ALARA principle in pediatric imaging and addressed issues associated with pediatric fluoroscopy and interventional imaging techniques. PMID:17412149

  10. Evolution as represented through argumentation: A qualitative study on reasoning and argumentation in high school biology teaching practices

    Science.gov (United States)

    Yalcinoglu, Pelin

    This study aimed to explore high school biology teachers' epistemological criteria and their attention to reasoning and argumentation within their instructional practices. This study investigated: (1) what epistemological criteria do high school biology teachers use when justifying the validity of conclusions, (2) what is the frequency of the explicit use of reasoning and argumentation, if any, in high school biology teachers' instructional practices, and to what extend are reasoning and argumentation skills reflected, if at all, in high school biology teachers' modes of assessment. Three different data collection methods were employed in this study; face-to-face interviews, classroom observations, and document collections. Teachers' epistemological criteria were investigated to provide insight about their reasoning structures. This investigation was made possible by having teachers provide an argument about the validity of hypothetical conclusions drawn by the students based on two different scenarios related to evolution. Toulmin's Argument Pattern used to create rubric to analyze high school biology teachers' levels of reasoning through argumentation. Results of the data analysis suggested following findings. First, high school biology teachers participated in this study presented variety of epistemological criteria which were presented as high, moderate and low levels of reasoning through the argumentations. Second, elements of Toulmin's Argument Pattern were visible in the participants teaching practices, however students were not explicitly introduced to a well structured argument in those classrooms. High level of reasoning was not evident in the instructional practices of the observed teachers. High school biology classrooms which were observed in this study do not provide opportunities for students to practice high level of reasoning or improve their argumentation skills. Third, Interview Protocols designed for this study were found useful to identify the

  11. Islamic Modernists and Discourse on Reason as a Reconciliatory Argument between Islam and the Western Enlightenment

    Directory of Open Access Journals (Sweden)

    ASMAHAN SALLAH

    2015-06-01

    Full Text Available This article examines the debates on the relationship between Islam and reason during the nineteenth century and early twentieth century. It argues that these debates were transnational but were largely influenced by similar debates in the Western tradition. It also affirms that modernists used discourse on reason to reconcile Islam with Western Enlightenment. The article illustrates the various mechanisms which Islamic modernists implemented to facilitate such reconciliation. These mechanisms include rationalization of miracles, contesting the concept of prophethood, and rejecting the scholarship of Islamic jurisprudence and theology. Based on writings by several Islamic modernists, such as their biographies of Prophet Muhammad, Quran commentaries, and magazine articles in different Islamic countries, I ascribe these mechanisms to a gap between logic and experimental thought, a gap which seeped into the mind of Islamic modernists under the influence of Western contemporary thinkers. While this discourse claims compatibility between Islam and Western Enlightenment, it also resists the binary of the sacred and the secular, a major legacy of the Western Enlightenment.

  12. LOCUS OF CONTROL AS A CORRELATE OF ACHIEVEMENT IN ENGLISH AS A SECOND LANGUAGE IN IBADAN

    Directory of Open Access Journals (Sweden)

    David O. FAKEYE

    2011-04-01

    Full Text Available The search for means of improving performance and consequently ameliorating declining achievement in English at public examinations have made it imperative for researchers to explore the psychological bases of academic achievement prominent among which is locus of control of learners. Its relationship with learners’ achievement in English. is the focus of this study. The descriptive research design was adopted in the study which attempted to provide answers to three research questions. The participants were 300 SSII students while locus of control scale ( r=.72 and English language achievement test r=.87 were the instruments used for data collection. Data were analyzed using Pearson Product Moment Correlation and t-test . Findings revealed that the locus of control of students positively correlates with their English Language achievement(r=.670; but students with internal and external locus of control did not differ significantly in their English Language achievement (t=.513;df=298;P<.05 .Based on these findings, it is recommended that teachers of English should factor learner’ locus of control into their instructional programmes for improved performance.

  13. THE PRINCIPLE OF REASONED SHAPE FORMING AS A BASIS FOR PLASTIC ADEQUACY OF DESIGN OBJECTS

    Directory of Open Access Journals (Sweden)

    Vitaly Vasilyevich Miroshnikov

    2015-08-01

    Full Text Available The article highlights the basic approaches to configuring the form in design. The authors analyze the main strategies of shape formation in modern design practices. The novelty of the subject is that the analysis is carried out in the context of the adequacy of the design of plastic objects. The essence of the problems outlined by the authors is inconsistency between the object’s semantics and its external form resulted from incorrect practices of shape formation. Consideration of strategies and tactics of configuration of forms is based on comparison of two principles of shape formation - intuitive and discursive. The aim of the authors is to identify the reasons and structural specificity of intuitive and discursive practices of shape formation in design and to show the priority of the discursive approach. Attention of the authors is focused on the differences of search algorithms and results of shaping which are characteristic for the principles under consideration. The arguments cited in the article determine the discursive strategy of form configuration as the most correct and efficient in terms of design engineering. In the process of analyzing the basic algorithms of shape formation, of topical importance is the concept of legitimacy of form as a definition of the most appropriate process and a results of the project research. The article gives the interpretation of legitimacy in terms of the project practices and design - education.

  14. Feasibility of Self-Reflection as a Tool to Balance Clinical Reasoning Strategies

    Science.gov (United States)

    Sibbald, Matthew; de Bruin, Anique B. H.

    2012-01-01

    Clinicians are believed to use two predominant reasoning strategies: system 1 based pattern recognition, and system 2 based analytical reasoning. Balancing these cognitive reasoning strategies is widely believed to reduce diagnostic error. However, clinicians approach different problems with different reasoning strategies. This study explores…

  15. `Grasp of Practice' as a Reasoning Resource for Inquiry and Nature of Science Understanding

    Science.gov (United States)

    Ford, Michael

    2008-02-01

    This article articulates how a ‘grasp of practice’ serves as a reasoning resource for inquiry and citizenship abilities associated with nature of science (NOS) understanding. Theoretically, this resource is elaborated through an overlapping concern with ‘practice’ in two literatures, science studies and psychology of learning, bringing attention to two key roles in scientific practice, Critiquers and Constructors of claims. Empirically, this resource is made plausible by the results of an expert-novice study and a classroom study. In the expert-novice study, reactions of scientists and laypeople to science-related claims in the popular media were contrasted, underlining the appropriate ways scientists tend to Critique such claims. In the classroom study, sixth-grade students engaged in a 2-week ramp experiment, experiencing first hand the roles of Critiquers and Constructors of claims, and were subsequently assessed with a novel experimental task. Performances suggest that students had attained a grasp of practice, going well beyond mere execution of methods or procedures. These results challenge a common assumption that declarative knowledge best characterizes learning targets for supporting inquiry and NOS understanding.

  16. The Theory of Reasoned Action as Parallel Constraint Satisfaction: Towards a Dynamic Computational Model of Health Behavior

    OpenAIRE

    Orr, Mark G; Thrush, Roxanne; Plaut, David C.

    2013-01-01

    The reasoned action approach, although ubiquitous in health behavior theory (e.g., Theory of Reasoned Action/Planned Behavior), does not adequately address two key dynamical aspects of health behavior: learning and the effect of immediate social context (i.e., social influence). To remedy this, we put forth a computational implementation of the Theory of Reasoned Action (TRA) using artificial-neural networks. Our model re-conceptualized behavioral intention as arising from a dynamic constrain...

  17. Critical Thinking: Ethical Reasoning as Essential to Fairminded Critical Thinking, Part IV

    Science.gov (United States)

    Elder, Linda; Paul, Richard

    2010-01-01

    In the last three columns, the authors introduced the idea of ethical reasoning, discussed its importance to education, and briefly dealt with a number of understandings essential to skilled ethical reasoning. In this column, the authors continue this discussion. They distinguish between simple and complex ethical questions and reason through an…

  18. Using Garlic As A Far-Transfer Problem of Proportional And Probabilistic Reasoning

    CERN Document Server

    Moore, N T

    2008-01-01

    The work describes a general problem, which emphasizes proportional reasoning and probabilistic reasoning skills in the context of planting garlic in a backyard garden. Along with practicing these reasoning skills in a context far-removed from the standard high school or college curriculum, our solution involves the development of a few relatively sophisticated statistical concepts, specifically histograms and confidence intervals.

  19. Fluid intellingence and spatial reasoning as predictors of pilot training performance in the South African Air Force (SAAF

    Directory of Open Access Journals (Sweden)

    François de Kock

    2009-04-01

    Full Text Available Pilot selection is a form of high-stakes selection due to the massive costs of training, high trainee ability requirements and costly repercussions of poor selection decisions. This criterion-related validation study investigated the predictive ability of fluid intelligence and spatial reasoning in predicting three criteria of pilot training performance, using an accumulated sample of South African Air Force pilots (N = 108. Hierarchical multiple regression analyses with training grade achieved as criterion were performed for each of the phases of training, namely practical flight training, ground school training, and officers’ formative training. Multiple correlations of 0.35 (p < 0.01, 0.20 (p > 0.05 and 0.23 (p > 0.05 were obtained for flight, ground school and formative training results, respectively. Spatial ability had incremental validity over fluid intelligence for predicting flight training performance.

  20. A New Look at the Old Problem of a Reasonable Expectation: The Reasonableness of Repeated Renewals of Fixed Term Contracts as Opposed to Indefinite Employment

    Directory of Open Access Journals (Sweden)

    E Gericke

    2011-04-01

    Full Text Available In South Africa, the Labour Relations Act 66 of 1995 (LRA regulates and protects the position of the employee who reasonably expects that a fixed-term contract will be renewed on the same or similar terms while the employer only offered to renew the contract on less favourable terms or in some instances was not prepared torenew the fixed-term contract at all. The LRA regards the latter conduct as a dismissal, as long as the employee can prove that the employer was responsible for creating the reasonable expectation of contractual renewal. In contrast to this position, the LRA does not regulate or protect the position of the employee whose fixed-term contract was repeatedly renewed on the same, similar or even improved terms, while the employer was in a position to offer the employee indefinite employment. The employer may even have created a reasonable expectation that repeated renewals would result in permanent employment. The exploitation and abuse of the fixed-term contract to the extent that an employee is deprived of employment security and the benefits linked to an employment relationship of indefinite duration have prompted a comparative investigation into this particular field of law.

  1. "As Long as You Work Hard, You Can Achieve Your Goals" : Hungarian Immigrants on the American Dream

    OpenAIRE

    Orsolya Kolozsvari

    2012-01-01

    Immigrants to the United States frequently perceive America as the land of endless opportunities and prosperity, and this perception is very frequently a propelling force in the decision for immigration. Through 20 in-depth interviews with middle-class Hungarians who live in the United States I will discuss how immigration to the United States has influenced the perceptions of these Hungarians of opportunities in the United States. I will also highlight how reasons for immigration and percept...

  2. Children's Reasoning as Collective Social Action through Problem Solving in Grade 2/3 Science Classrooms

    Science.gov (United States)

    Kim, Mijung

    2016-01-01

    Research on young children's reasoning show the complex relationships of knowledge, theories, and evidence in their decision-making and problem solving. Most of the research on children's reasoning skills has been done in individualized and formal research settings, not collective classroom environments where children often engage in learning and…

  3. Mental state decoding v. mental state reasoning as a mediator between cognitive and social function in psychosis

    OpenAIRE

    Corvin, Aiden; Donohoe, Gary; Gill, Michael

    2008-01-01

    Theory of mind deficits in schizophrenia have been parsed into mental state reasoning and mental state decoding components. We report that mental state decoding as measured by the `Eyes task? better predicted social function than mental state reasoning as measured by the `Hinting task? in 73 out-patients with chronic schizophrenia. Mental state decoding task performance also partly mediated the influence of basic neuropsychological performance on social function. We discuss these findings in ...

  4. Anxiety and Inattention as Predictors of Achievement in Early Elementary School Children

    OpenAIRE

    Grills-Taquechel, Amie E.; Fletcher, Jack M.; Vaughn, Sharon R.; Denton, Carolyn A.; Taylor, Pat

    2012-01-01

    The objective of this study was to examine the relations among anxiety, inattention, and math/reading achievement, as well as the mediating/moderating role of inattention in the anxiety-achievement association both concurrently and longitudinally. Participants included 161 ethnically diverse children (aged 6–8) and their teachers. At the middle and end of first-grade (approximately 5 months apart), students completed measures of anxiety and achievement while their teachers completed a measure...

  5. Low Wages as Occupational Health Hazards.

    Science.gov (United States)

    Leigh, J Paul; De Vogli, Roberto

    2016-05-01

    The history of occupational medicine has been characterized by ever-widening recognition of hazards, from fires in 1911 to asbestos in the 1960s, to job strain in the 1990s. In this essay, we argue for broadening the recognition further to include low wages. We first review possible mechanisms explaining the effects of wages on health or health behaviors. Mechanisms involve self-esteem, job satisfaction, deprivation, social rank, the "full" price of bad health, patience, and the ability to purchase health-producing goods and services. Second, we discuss empirical studies that rely on large, typically national, data sets and statistical models that use either instrumental variables or natural experiments and also account for other family income. Finally, we draw implications for laws governing minimum wages and labor unions. PMID:27158950

  6. Foreign Language Learning Aptitudes, Attitudes, Attributions, and Achievement of Postsecondary Students Identified as Gifted

    Science.gov (United States)

    Bain, Sherry K.; McCallum, R. Steve; Bell, Sherry Mee; Cochran, Jeff L.; Sawyer, Stephani Choate

    2010-01-01

    We investigated the aptitudes, attitudes, attributions, and achievement of undergraduates identified as gifted who were taking a beginning Spanish course, and compared these characteristics to undergraduates in the same cohort group who had not been identified as gifted. There were differences in the aptitudes, attitudes, and achievement of…

  7. Retrocausal Effects as a Consequence of Quantum Mechanics Refined to Accommodate the Principle of Sufficient Reason

    Energy Technology Data Exchange (ETDEWEB)

    Stapp, Henry P.

    2011-05-10

    The principle of sufficient reason asserts that anything that happens does so for a reason: no definite state of affairs can come into being unless there is a sufficient reason why that particular thing should happen. This principle is usually attributed to Leibniz, although the first recorded Western philosopher to use it was Anaximander of Miletus. The demand that nature be rational, in the sense that it be compatible with the principle of sufficient reason, conflicts with a basic feature of contemporary orthodox physical theory, namely the notion that nature's response to the probing action of an observer is determined by pure chance, and hence on the basis of absolutely no reason at all. This appeal to pure chance can be deemed to have no rational fundamental place in reason-based Western science. It is argued here, on the basis of the other basic principles of quantum physics, that in a world that conforms to the principle of sufficient reason, the usual quantum statistical rules will naturally emerge at the pragmatic level, in cases where the reason behind nature's choice of response is unknown, but that the usual statistics can become biased in an empirically manifest way when the reason for the choice is empirically identifiable. It is shown here that if the statistical laws of quantum mechanics were to be biased in this way then the basically forward-in-time unfolding of empirical reality described by orthodox quantum mechanics would generate the appearances of backward-time-effects of the kind that have been reported in the scientific literature.

  8. Retrocausal Effects as a Consequence of Quantum Mechanics Refined to Accommodate the Principle of Sufficient Reason

    International Nuclear Information System (INIS)

    The principle of sufficient reason asserts that anything that happens does so for a reason: no definite state of affairs can come into being unless there is a sufficient reason why that particular thing should happen. This principle is usually attributed to Leibniz, although the first recorded Western philosopher to use it was Anaximander of Miletus. The demand that nature be rational, in the sense that it be compatible with the principle of sufficient reason, conflicts with a basic feature of contemporary orthodox physical theory, namely the notion that nature's response to the probing action of an observer is determined by pure chance, and hence on the basis of absolutely no reason at all. This appeal to pure chance can be deemed to have no rational fundamental place in reason-based Western science. It is argued here, on the basis of the other basic principles of quantum physics, that in a world that conforms to the principle of sufficient reason, the usual quantum statistical rules will naturally emerge at the pragmatic level, in cases where the reason behind nature's choice of response is unknown, but that the usual statistics can become biased in an empirically manifest way when the reason for the choice is empirically identifiable. It is shown here that if the statistical laws of quantum mechanics were to be biased in this way then the basically forward-in-time unfolding of empirical reality described by orthodox quantum mechanics would generate the appearances of backward-time-effects of the kind that have been reported in the scientific literature.

  9. A novel method to achieve selective emitter for silicon solar cell using low cost pattern-able a-Si thin films as the semi-transparent phosphorus diffusion barrier

    International Nuclear Information System (INIS)

    Highlights: ► a-Si thin films as semitransparent phosphorus diffusion barriers for solar cell. ► a-Si thin films on silicon wafers were patterned by the alkaline solution. ► Selective emitter was formed with patterned a-Si as diffusion barrier for solar cell. -- Abstract: Selective emitter for silicon solar cell was realized by employing a-Si thin films as the semi-transparent diffusion barrier. The a-Si thin films with various thicknesses (∼10–40 nm) were deposited by the electron-beam evaporation technique. Emitters with sheet resistances from 37 to 145 Ω/□ were obtained via POCl3 diffusion process. The thickness of the a-Si diffusion barrier was optimized to be 15 nm for selective emitter in our work. Homemade mask which can dissolve in ethanol was screen-printed on a-Si film to make pattern. The a-Si film was then patterned in KOH solution to form finger-like design. Selective emitter was obtainable with one-step diffusion with patterned a-Si film on. Combinations of sheet resistances for the high-/low-level doped regions of 39.8/112.1, 36.2/88.8, 35.4/73.9 were obtained. These combinations are suitable for screen-printed solar cells. This preparation method of selective emitter based on a-Si diffusion barrier is a promising approach for low cost industrial manufacturing.

  10. Theories of Reasoned Action and Planned Behavior as Models of Condom Use: A Meta-Analysis

    OpenAIRE

    Albarracín, Dolores; Johnson, Blair T.; Fishbein, Martin; Muellerleile, Paige A.

    2001-01-01

    To examine how well the theories of reasoned action and planned behavior predict condom use, the authors synthesized 96 data sets (N = 22,594) containing associations between the models’ key variables. Consistent with the theory of reasoned action’s predictions, (a) condom use was related to intentions (weighted mean r. = .45), (b) intentions were based on attitudes (r. = .58) and subjective norms (r. = .39), and (c) attitudes were associated with behavioral beliefs (r. = .56) and norms were ...

  11. Hermeneutics of reason: the principle of common rationality as premise of understanding the Other(s)

    OpenAIRE

    Mihai Stelian Rusu

    2013-01-01

    The central argument defended in this paper is made up of two interconnected statements: i) that a minimally defined rationality is an anthropological constant, being shared by all conceivable human cultures; and ii) that this “commonality of reason” constitutes the basis on which inter-cultural understanding is possible. In proving the first thesis (the universality of reason), the paper contrasts Western thought, epitomized in scientific reason, with non-Western thinking patterns, expressed...

  12. Reasons and Outcomes of Work-Family Conflict and Work Alienation as one of Its Outcomes

    Directory of Open Access Journals (Sweden)

    Seyed Abdolhossein Nabavi

    2014-11-01

    research expectations of social support role and its effects on work alienation. It appears that the effectiveness of social support can influence work alienation through expectations of work role, work ambiguity and work- family conflict. In other words, expectations of work role and work role ambiguity are effective on work alienation through family-work conflict. It is necessary to mention that there is a significant and reverse relationship between work control and work alienation. Organizational managers can have happy and satisfied personnel, who give their effective performance and show interest, loyalty and commitment to the organization, if they help them to make a balance between work and life. As the results indicate, establishing a balance between work and family is of great value. Achieving this end requires that managers select an approach in which employees' and organization’s interests could be synchronously considered. They should abandon traditional attitudes on the relationship between work and life. Therefore, in order to prevent the negative consequences of work-family conflict, which are sometimes irreparable, it is recommended that employees become familiar with scientific management of conflict, and be supported comprehensively by their family members and coworkers. Thus, they will have more freedom and flexibility, and minimum conflict will be seen in their work and family programs. On the other hand, it is necessary to improve and reform occupational laws and rules.

  13. Nonstoichiometric Low-Temperature Grown GaAs Nanowires.

    Science.gov (United States)

    Díaz Álvarez, Adrian; Xu, Tao; Tütüncüoglu, Gözde; Demonchaux, Thomas; Nys, Jean-Philippe; Berthe, Maxime; Matteini, Federico; Potts, Heidi A; Troadec, David; Patriarche, Gilles; Lampin, Jean-François; Coinon, Christophe; Fontcuberta i Morral, Anna; Dunin-Borkowski, Rafal E; Ebert, Philipp; Grandidier, Bruno

    2015-10-14

    The structural and electronic properties of nonstoichiometric low-temperature grown GaAs nanowire shells have been investigated with scanning tunneling microscopy and spectroscopy, pump-probe reflectivity, and cathodoluminescence measurements. The growth of nonstoichiometric GaAs shells is achieved through the formation of As antisite defects, and to a lower extent, after annealing, As precipitates. Because of the high density of atomic steps on the nanowire sidewalls, the Fermi level is pinned midgap, causing the ionization of the subsurface antisites and the formation of depleted regions around the As precipitates. Controlling their incorporation offers a way to obtain unique electronic and optical properties that depart from the ones found in conventional GaAs nanowires. PMID:26339987

  14. Hermeneutics of reason: the principle of common rationality as premise of understanding the Other(s

    Directory of Open Access Journals (Sweden)

    Mihai Stelian Rusu

    2013-06-01

    Full Text Available The central argument defended in this paper is made up of two interconnected statements: i that a minimally defined rationality is an anthropological constant, being shared by all conceivable human cultures; and ii that this “commonality of reason” constitutes the basis on which inter-cultural understanding is possible. In proving the first thesis (the universality of reason, the paper contrasts Western thought, epitomized in scientific reason, with non-Western thinking patterns, expressed by ethno-sciences, magic rituals, and other knowledge practices. The conclusion drawn from this comparison is that both modern scientific reason and non-literate peoples thought patterns are two “cognitive modes” sharing a strong structural similarity. Building on some loci classici of anthropological literature written by Malinowski, Evans-Pritchard, and Lévi-Strauss (among others, the paper argues that although modern Western science and indigenous knowledge(s share a common rational denominator, the two cognitive modes are nonetheless hierarchical, the former being epistemically superior to the latter thanks to its unique self-correcting methodology. The paper ends by arguing the case for the possibility of understanding the Other(s by way of reason, a possibility grounded on the commonality of reason between cultures.

  15. What counts as a reasonable extent? - a systems approach for understanding fire safety in Sweden

    OpenAIRE

    Larsson, Miranda; Grunnesjö, Erik; Bergström, Johan

    2012-01-01

    Swedish legislation requires that any owner or user of a building maintain a reasonable level of fire protection measures to ensure the safety of all people located in the building. If a building, in the wake of a fire, in court is determined not to have had a reasonable fire protection, the blame will likewise be assigned to the building owner or user. Using the perspective of risk governance, this study aims at analysing how regulation and stakeholders interact to maintain a specific level ...

  16. Reasons for Cannabis Use and Effects of Cannabis Use as Reported by Patients with Psychotic Disorders

    NARCIS (Netherlands)

    N. Dekker; D.H. Linszen; L. de Haan

    2009-01-01

    Background: Cannabis is one of the most commonly used substances in patients with a psychotic disorder and is associated with a higher risk of psychotic relapses. Identifying reasons for cannabis use and subjective effects in patients with psychotic disorders can provide insight into the functions o

  17. Analogical Reasoning as a Decision Support Principle for Weakly-Structured Marketing Problems

    NARCIS (Netherlands)

    N.A.P. Althuizen (Niek)

    2006-01-01

    textabstractMany marketing problems are weakly-structured. From the psychological literature, we know that analogical reasoning is an effective problem-solving method in weakly-structured decision situations. That is, when confronted with such a problem, one of the first things managers will natural

  18. What Counts as a Reasonable Adjustment? Dyslexic Students and the Concept of Fair Assessment

    Science.gov (United States)

    Riddell, Sheila; Weedon, Elisabet

    2006-01-01

    This article focuses on the construction of dyslexia in higher education and explores the nature of negotiations between students, lecturers and academic institutions over diagnosis, support and assessment. Disabled students are now entitled, under the terms of the Disability Discrimination Act (DDA), to reasonable adjustments in assessment.…

  19. Oppositional Defiance, Moral Reasoning and Moral Value Evaluation as Predictors of Self-Reported Juvenile Delinquency

    Science.gov (United States)

    Beerthuizen, Marinus G. C. J.; Brugman, Daniel; Basinger, Karen S.

    2013-01-01

    This study investigated the relationships among oppositional defiant attitudes, moral reasoning, moral value evaluation and self-reported delinquent behaviour in adolescents ("N" = 351, "M"[subscript AGE] = 13.8 years, "SD"[subscript AGE] = 1.1). Of particular interest were the moderating effects of age, educational…

  20. Emotional Intelligence and Gender as Predictors of Academic Achievement among Some University Students in Barbados

    OpenAIRE

    Grace A. Fayombo

    2012-01-01

    This study investigated emotional intelligence (attending to emotion, positive expressivity and negative expressivity) and gender as predictors of academic achievement among 163 undergraduate psychology students in The University of the West Indies (UWI), Cave Hill Campus, Barbados. Results revealed significant positive and negative correlations among academic achievement, emotional intelligence components and gender. Additionally, using the stepwise multiple regression analysis, it was found...

  1. International Comparisons of Student Achievement as Indicators for Educational Policy in Slovenia

    Science.gov (United States)

    Straus, Mojca

    2005-01-01

    At the time of the development of the new curriculum in Slovenia, international comparative data providing information on the performance of Slovene students as compared to other relevant countries were available from a limited number of assessments. For this reason, it was even more important that additional international comparisons were…

  2. Voices from Social Work Graduates in China: Reasons for Not Choosing Social Work as a Career.

    Science.gov (United States)

    Zeng, Shouchui; Cheung, Monit; Leung, Patrick; He, Xuesong

    2016-01-01

    Although previous studies have addressed turnover issues after being a social worker, this study identifies factors that may block initial entry to the profession. Using a semistructural interview method with 20 BSW graduates, the researchers transcribed the reasons for BSW graduates not entering a career in social work. Through element-centered content analysis, 76 reasons were sorted into nine categories: (1) income insufficient for basic needs, (2) unclear future, (3) no commitment to social work, (4) social work jobs could be taken by other professionals, (5) difficulties in actualizing proclaimed value, (6) personally unable to apply skills, (7) social exclusion due to nonresident status, (8) hard/stressful work, and (9) not supported by peers and family. Through person-centered content analysis, most respondents (90 percent) reported multiple reasons (M = 3.8) supporting their decision, offering their rational thought processes culminating in the decision not to enter social work. Recommendations for developing a national survey, engaging social workers in preparing BSW students for graduation, and modifying student admissions strategies are discussed. PMID:26898001

  3. Of Pigs and Men: Understanding Students' Reasoning about the Use of Pigs as Donors for Xenotransplantation

    Science.gov (United States)

    Lindahl, Mats Gunnar

    2010-01-01

    Two important roles of education are to provide students with knowledge for their democratic participation in society and to provide knowledge for a future profession. In science education, students encounter values that may be in conflict with their worldview. Such conflicts may, for example, lead to constructive reflections as well as rejection…

  4. Learning strategies and general cognitive ability as predictors of gender- specific academic achievement

    OpenAIRE

    Ruffing, Stephanie; Wach, F.-Sophie; Spinath, Frank M.; Brünken, Roland; Karbach, Julia

    2015-01-01

    Recent research has revealed that learning behavior is associated with academic achievement at the college level, but the impact of specific learning strategies on academic success as well as gender differences therein are still not clear. Therefore, the aim of this study was to investigate gender differences in the incremental contribution of learning strategies over general cognitive ability in the prediction of academic achievement. The relationship between these variables was examined by ...

  5. Intelligence and Metacognition as Predictors of Foreign Language Achievement: A Structural Equation Modeling Approach

    Science.gov (United States)

    Pishghadam, Reza; Khajavy, Gholam Hassan

    2013-01-01

    This study examined the role of metacognition and intelligence in foreign language achievement on a sample of 143 Iranian English as a Foreign Language (EFL) learners. Participants completed Raven's Advanced Progressive Matrices as a measure of intelligence, and Metacognitive Awareness Inventory as a measure of metacognition. Learners' scores at…

  6. Learning strategies and general cognitive ability as predictors of gender- specific academic achievement.

    Science.gov (United States)

    Ruffing, Stephanie; Wach, F-Sophie; Spinath, Frank M; Brünken, Roland; Karbach, Julia

    2015-01-01

    Recent research has revealed that learning behavior is associated with academic achievement at the college level, but the impact of specific learning strategies on academic success as well as gender differences therein are still not clear. Therefore, the aim of this study was to investigate gender differences in the incremental contribution of learning strategies over general cognitive ability in the prediction of academic achievement. The relationship between these variables was examined by correlation analyses. A set of t-tests was used to test for gender differences in learning strategies, whereas structural equation modeling as well as multi-group analyses were applied to investigate the incremental contribution of learning strategies for male and female students' academic performance. The sample consisted of 461 students (mean age = 21.2 years, SD = 3.2). Correlation analyses revealed that general cognitive ability as well as the learning strategies effort, attention, and learning environment were positively correlated with academic achievement. Gender differences were found in the reported application of many learning strategies. Importantly, the prediction of achievement in structural equation modeling revealed that only effort explained incremental variance (10%) over general cognitive ability. Results of multi-group analyses showed no gender differences in this prediction model. This finding provides further knowledge regarding gender differences in learning research and the specific role of learning strategies for academic achievement. The incremental assessment of learning strategy use as well as gender-differences in their predictive value contributes to the understanding and improvement of successful academic development. PMID:26347698

  7. Learning strategies and general cognitive ability as predictors of gender- specific academic achievement

    Directory of Open Access Journals (Sweden)

    Stephanie eRuffing

    2015-08-01

    Full Text Available Recent research has revealed that learning behavior is associated with academic achievement at the college level, but the impact of specific learning strategies on academic success as well as gender differences therein are still not clear. Therefore, the aim of this study was to investigate gender differences in the incremental contribution of learning strategies over general cognitive ability in the prediction of academic achievement. The relationship between these variables was examined by correlation analyses. A set of t-tests was used to test for gender differences in learning strategies, whereas structural equation modelling as well as multi-group analyses were applied to investigate the incremental contribution of learning strategies for male and female students’ academic performance. The sample consisted of 461 students (mean age=21.2 years, SD=3.2. Correlation analyses revealed that general cognitive ability as well as the learning strategies effort, attention, and learning environment were positively correlated with academic achievement. Gender differences were found in the reported application of many learning strategies. Importantly, the prediction of achievement in structural equation modeling revealed that only effort explained incremental variance (10% over general cognitive ability. Results of multi-group analyses showed no gender differences in this prediction model. This finding provides further knowledge regarding gender differences in learning research and the specific role of learning strategies for academic achievement. The incremental assessment of learning strategy use as well as gender-differences in their predictive value contributes to the understanding and improvement of successful academic development.

  8. Using a multi-agent evidential reasoning network as the objective function for an evolutionary algorithm

    Science.gov (United States)

    Woodley, Robert; Lindahl, Eric; Barker, Joseph

    2007-04-01

    A culturally diverse group of people are now participating in military multinational coalition operations (e.g., combined air operations center, training exercises such as Red Flag at Nellis AFB, NATO AWACS), as well as in extreme environments. Human biases and routines, capabilities, and limitations strongly influence overall system performance; whether during operations or simulations using models of humans. Many missions and environments challenge human capabilities (e.g., combat stress, waiting, fatigue from long duty hours or tour of duty). This paper presents a team selection algorithm based on an evolutionary algorithm. The main difference between this and the standard EA is that a new form of objective function is used that incorporates the beliefs and uncertainties of the data. Preliminary results show that this selection algorithm will be very beneficial for very large data sets with multiple constraints and uncertainties. This algorithm will be utilized in a military unit selection tool.

  9. Quantum theory as plausible reasoning applied to data obtained by robust experiments.

    Science.gov (United States)

    De Raedt, H; Katsnelson, M I; Michielsen, K

    2016-05-28

    We review recent work that employs the framework of logical inference to establish a bridge between data gathered through experiments and their objective description in terms of human-made concepts. It is shown that logical inference applied to experiments for which the observed events are independent and for which the frequency distribution of these events is robust with respect to small changes of the conditions under which the experiments are carried out yields, without introducing any concept of quantum theory, the quantum theoretical description in terms of the Schrödinger or the Pauli equation, the Stern-Gerlach or Einstein-Podolsky-Rosen-Bohm experiments. The extraordinary descriptive power of quantum theory then follows from the fact that it is plausible reasoning, that is common sense, applied to reproducible and robust experimental data. PMID:27091169

  10. Baby cuff as a reason for laryngeal mask airway cuff malfunction during airway management for anesthesia

    OpenAIRE

    Jafar Rahimi Panahi; Ata Mahmoodpoor; Golzari, Samad E. J.; Hassan Soleimanpour

    2014-01-01

    Placement of laryngeal mask airway (LMA) is a blind procedure without requiring laryngoscopy. The reported success rate for LMA insertion at the first attempt is almost 95%; however, many functioning LMAs may not be in an ideal anatomic place. It seems that disposable LMAs have more stable cuff pressure compared to reusable LMAs; therefore, Anesthesiologists should bear in mind this fact when using reusable LMAs to achieve a proper sealing and safe airway management. In this report, we introd...

  11. Reasons for Errors Done by Belarusian Learners Learning Turkish as a Foreign Language

    Science.gov (United States)

    Tum, Gulden

    2012-01-01

    Teaching Turkish as a Foreign Language (TFL) has gained importance recently and several studies are carried out in this field. Especially, learners of linguistically different communities (Byelorussian/Russian) are observed to make errors while learning Turkish. If making errors is an integral outcome in learning a TFL, then to what extent is it…

  12. The Risk of a Halo Bias as a Reason to Keep Students Anonymous during Grading

    Science.gov (United States)

    Malouff, John M.; Emmerton, Ashley J.; Schutte, Nicola S.

    2013-01-01

    Experts have advocated anonymous grading as a means of eliminating actual or perceived evaluator bias in subjective student assessment. The utility of anonymity in assessment rests on whether information derived from student identity can unduly influence evaluation. The halo effect provides a conceptual background for why a bias might occur. In…

  13. Moral Development as the Personal Education of Feeling and Reason: From James to Piaget

    Science.gov (United States)

    Ferrari, Michel; Okamoto, Carol M.

    2003-01-01

    This article traces the connection between William James's writings in "The Varieties of Religious Experience" and Jean Piaget's work on moral development through Piaget's early work on religious experience. James characterises religious experience as unlocking deep personal power that can sustain a "strenuous mood". These ideas impacted the early…

  14. Physical Activity as a Moderator of the Relationship between Aging and Inductive Reasoning

    Science.gov (United States)

    Perrot, Alexandra; Gagnon, Christine; Bertsch, Jean

    2009-01-01

    A relatively universal observation in aging studies is that cognitive functions inevitably decline across the adult life span. More specifically, executive functions decline substantially with age, as do the frontal and prefrontal brain regions that support them. Indeed, these regions are subject to important neurological modifications with…

  15. Natural disasters as one of the reasons for the existence of insurance

    OpenAIRE

    Oksana Syslyakova

    2014-01-01

    In work the essence and types of natural disasters are considered, dynamics and structure of emergency events in Russia in 2010-2013 is analysed, need of application of insurance as effective mechanism of protection of the state and society from various natural disasters is proved.

  16. The Interrogative Model of inquiry as a logic of scientific reasoning

    OpenAIRE

    Mutanen, Arto

    2011-01-01

    Questioning has been understood as a general method for knowledge seeking in philosophy for thousands of years. The first systematic questioning approach in the (written) history of philosophy is the Socratic Method of Questioning (elenchus). The strategy of questioning is the central part of the Socratic Method of Questioning. Hintikka has developed a logico-philosophical model called the Interrogative Model of Inquiry, in which he systematizes the questioning method. The notion of strategy ...

  17. Five Good Reasons for Engineering as the Focus for Technology Education

    OpenAIRE

    Wicklein, Robert C.

    2006-01-01

    The article presents information on a paper which discusses why engineering design should be the focus for technology education. Technology education is still viewed as a non-essential instructional program and this is because school administrators and counselors have inadequate understanding of it. Even general populace have inadequate understanding concerning technology education. The pervasiveness of technology literally affects every living creature in our society. Therefore, it is of cri...

  18. Reasons and Outcomes of Work-Family Conflict and Work Alienation as one of Its Outcomes

    OpenAIRE

    Seyed Abdolhossein Nabavi; Marzieh Shahryari

    2014-01-01

    Introduction Appearance and increasing development of families with both partners employed is regarded as a social revolution in Iran. There are many pressures in this type of family life due to inefficiency of the traditional opinion about division of labor in family. One of the pressures stems from work-family conflict in which sometimes there is no solution and causes many unpredictable outcomes for social cohesion, family performance, individual work performance and also work alienatio...

  19. Poor glycemic control as a reason for referral of diabetes patients to specialists in Israel

    OpenAIRE

    Fogelman, Yacov; Karkabi, Khaled; Goldfracht, Margalit

    2016-01-01

    Aims/introduction: Family physicians face the dilemma of when to refer patients with diabetes to specialists. This study examined attitudes of family physicians to referring patients with poor glucose control to diabetes specialists.Materials and methods: At continuous medical education courses, family physicians were asked to respond anonymously, as to whether they generally manage the diabetes of their patients, and specifically those with poor glycemic control (HbA1c>9.0%).Results: Of 4...

  20. Intervention, causal reasoning, and the neurobiology of mental disorders: Pharmacological drugs as experimental instruments.

    Science.gov (United States)

    Tsou, Jonathan Y

    2012-06-01

    In psychiatry, pharmacological drugs play an important experimental role in attempts to identify the neurobiological causes of mental disorders. Besides being developed in applied contexts as potential treatments for patients with mental disorders, pharmacological drugs play a crucial role in research contexts as experimental instruments that facilitate the formulation and revision of neurobiological theories of psychopathology. This paper examines the various epistemic functions that pharmacological drugs serve in the discovery, refinement, testing, and elaboration of neurobiological theories of mental disorders. I articulate this thesis with reference to the history of antipsychotic drugs and the evolution of the dopamine hypothesis of schizophrenia in the second half of the twentieth century. I argue that interventions with psychiatric patients through the medium of antipsychotic drugs provide researchers with information and evidence about the neurobiological causes of schizophrenia. This analysis highlights the importance of pharmacological drugs as research tools in the generation of psychiatric knowledge and the dynamic relationship between practical and theoretical contexts in psychiatry. PMID:22520203

  1. Intelligence And Self-concept As Co-relates Of Academic Achievement

    Directory of Open Access Journals (Sweden)

    Paramjeet Singh Bhadwal

    2012-10-01

    Full Text Available The main purpose of this study is to explore the correlation between intelligence and academic achievement, self-concept and academic achievement among high school students in Jammu city. Two hundred-fifty five students (ninth graders participated in this study. 142 of whom were female students and 113 were male students. Pearson's Product Moment Coefficient of Correlation was employed for data analysis. Results indicated that there was significant positive relationship between the variables of Intelligence and academic achievement in case of boys and girls studying in secondary schools. Furthermore, there was significant negative relationship between the variables self-concept and academic achievement in case of boys and significant positive relationship between the variables of self-concept and academic achievement in case of girls. It was revealed that with the increase in the intelligence, the academic achievement also increases in case of boys as well as girls of secondary schools. However, the variables of self-concept and academic achievement are inversely related to each other in case of boys and positively related in case of girls.

  2. FACEBOOK AS A SOCIALISING AGENT AND ITS IMPACT ON ACADEMIC ACHIEVEMENT OF AN INDIVIDUAL

    OpenAIRE

    Prakasha G. S; Jacqueline Bareh

    2013-01-01

    This article is aiming at creating awareness towards Face-book as a socializing agent and its impact on academic achievement of individuals pursuing education at various levels. Facebook a social networking site very widely used by teenagers and it has both positive and negative effects on an individual over his academic life as well as his or her social life. As parents, teachers and civilians it is very important to understand what goes on in there and what is its aftermath ...

  3. A STUDY OF ADOLESCENTS’ ANXIETY AND ACHIEVEMENT IN ENGLISH AS A FOREIGN LANGUAGE

    Directory of Open Access Journals (Sweden)

    Ridha Fadillah

    2011-10-01

    Full Text Available This paper aims at investigating whether there is relationship between students’ anxiety and students’ achievement in English as a foreign language among adolescents at Sekolah Menengah Umum Negeri 1 Banjarbaru, South Kalimantan. The sample was 152 students of sixteen and seventeen years old at second grade. The results indicate that the students’ anxiety in learning English as foreign language is at moderate level. There is no significant relationship between English language anxiety and students’ achievement in English as a foreign language as a whole. But a significant negative correlation between test anxiety and students’ achievement is indicated. And the difference of English language anxiety between male and female occurred on communication apprehension, it shows that female is more apprehensive than male in English communication but for overall anxiety, there is no difference in English language anxiety by gender at second grade in this school.

  4. State downsizing as a determinant of infant mortality and achievement of Millennium Development Goal 4

    OpenAIRE

    Palma Solís, Marco Antonio; Álvarez-Dardet Díaz, Carlos; Franco Giraldo, Álvaro; Hernández Aguado, Ildefonso; Pérez Hoyos, Santiago

    2009-01-01

    The aim of this study was to evaluate the worldwide effect of state downsizing policies on achievement of U.N. Millennium Development Goal 4 (MDG4) on infant mortality rates. In an ecological retrospective cohort study of 161 countries, from 1978 to 2002, the authors analyzed changes in government consumption (GC) as determining exposure to achievement of MDG4. Descriptive methods and a multiple logistic regression were applied to adjust for changes in gross domestic product, level of democra...

  5. Making Methods Work in Software Engineering : Method Deployment - as a Social Achievement

    OpenAIRE

    Rönkkö, Kari

    2005-01-01

    The software engineering community is concerned with improvements in existing methods and development of new and better methods. The research approaches applied to take on this challenge have hitherto focused heavily on the formal and specifying aspect of the method. This has been done for good reasons, because formalizations are the means in software projects to predict, plan, and regulate the development efforts. As formalizations have been successfully developed new challenges have been re...

  6. Haag's Theorem as a Reason to Reconsider Direct-Action Theories

    CERN Document Server

    Kastner, R E

    2015-01-01

    It is argued that the severe consequences of Haag's inconsistency theorem for relativistic quantum field theories can be successfully evaded in the direct-action approach. Some recent favorable comments of John Wheeler, often mistakenly presumed to have abandoned his own (and Feynman's) direct-action theory, together with the remarkable immunity of direct-action quantum electrodynamics to Haag's theorem, suggest that it may well be a good time to rehabilitate direct action theories. It is also noted that, as extra dividends, direct-action QED is immune to the self-energy problem of standard gauge field QED, and can also provide a solution to the problem of gauge arbitrariness.

  7. Science achievement as an indicator of educational opportunity available in rural K--12 districts in Texas

    Science.gov (United States)

    Capehart, Cheryl Louise

    Purpose of the study. This study examined Rural K--12 Texas districts to investigate whether science achievement could serve as a gauge to measure the availability and quality of rigorous educational opportunities in Rural Texas districts. Procedure. A Case II criterion-group design was used; 2 groups of districts were selected based on their 3-year performances on the 8th grade Science Texas Assessment of Academic Skills (TAAS)---the statewide criterion-referenced test. The High Performing Group (HPG) was composed of 30 top performing districts; the Low Performing Group (LPG) was composed of 30 lowest performing districts. Data collection was limited to archived quantitative data from Texas Education Agency's open records. Achievement variables were percent passing (1) Science TASS, (2) Biology End-of-Course (EoC) test and (3) the composite passing all Reading, Writing, and Mathematics TAAS. Academic variables were percent participating in (1) advanced courses, (2) rigorous graduation programs, and (3) college entrance examinations. District quality indicators also included 3 budget variables: (1) average teacher salary, (2) per pupil instructional expenditure, (3) percent allocated for instructional leadership; and 4 staff variables: (1) percent teachers fully certified, (2) percent teachers with advanced degrees, (3) average years teacher experience, (4) average percent non-turnover of teachers. One score per variable was obtained for each district. The HPG and LPG were compared on each variable using the group means, standard deviations, standard errors of the mean, Levene's test for equality of variance, and a t test for equality of means with a 95% confidence level. The Pearson correlation with two-tailed significance calculated the relationship of each independent variable (budget and staff factors) to each dependent variable (performance measures). Science TASS and a Combined Science score (grand mean of Science TASS & Biology EoC passing rates) were

  8. Factors related to academic grades as a proxy for educational achievement

    Directory of Open Access Journals (Sweden)

    Ianina Tuñón

    2016-01-01

    Full Text Available After eleven years of the Argentine government implementing different educational engagement policies, it is appropriate to look into the achievements in education. What sociodemographic, socioeconomic and sociocultural factors are linked to academic grades as a proxy for educational achievement in subjects such as Mathematics and Language in primary and secondary education? This study shows relatively well-known inequalities relating to sex and educational paths. Nevertheless, other influential sociocultural factors were explored which are relatively independent from socioeconomic and school administration factors, such as having books at home, reading behavior and storytelling. Moreover, the relationship between social stratification and the type of school management was identified. In order to achieve this, analyses were performed using logistic regression models based on microdata from the Argentine Social Debt Survey for 2011.

  9. Examination of the Relationship Between Autonomy and English Achievement as Mediated by Foreign Language Classroom Anxiety.

    Science.gov (United States)

    Ghorbandordinejad, Farhad; Ahmadabad, Roghayyeh Moradian

    2016-06-01

    This study investigated the relationship between autonomy and English language achievement among third-grade high school students as mediated by foreign language classroom anxiety in a city in the north-west of Iran. A sample of 400 students (187 males, and 213 females) was assessed for their levels of autonomy and foreign language anxiety using the Autonomy Questionnaire and Foreign Language Classroom Anxiety Scale (FLCAS), respectively. Participants' scores on their final English exam were also used as the measurement of their English achievement. The results of Pearson correlation revealed a strong correlation between learners' autonomy and their English achievement (r [Formula: see text] .406, n [Formula: see text] 400, [Formula: see text]). Also, foreign language classroom anxiety was found to be significantly and negatively correlated with English achievement (r [Formula: see text] [Formula: see text].472, n [Formula: see text] 400, [Formula: see text]). Hierarchical multiple regression was used to assess the ability of autonomy to predict language learning achievement, after controlling for the influence of anxiety. In sum, the results of hierarchical multiple regressions revealed that foreign language classroom anxiety significantly mediates the relationship between autonomy and English language achievement. Implications for both teachers and learners, and suggestions for further research are provided. PMID:25941040

  10. Longitudinal drift of substorm electrons as the reason of impulsive precipitation events and VLF emissions

    Directory of Open Access Journals (Sweden)

    A. A. Lubchich

    2006-10-01

    Full Text Available Using the data from satellite CRRES and three geostationary LANL spacecraft, the propagation of an electron cloud from midnight to the evening sector is investigated. An electron cloud was injected during a weak isolated substorm that developed on a quiet geomagnetic background. It is found that within the local time sector from 03:00 until at least 08:00 MLT, the propagation of electrons at perpendicular pitch-angles is well described by a simple model of drift in the dipole magnetic field. The flux levels in the field-aligned electrons increase simultaneously with the flux at perpendicular pitch angles, which is attributed to the pitch angle diffusion by the whistler mode. This pitch-angle diffusion leads to precipitation of electrons from a drifting cloud and an increase in the ionospheric electron density, simultaneously observed above Tromsø, Norway, by the EISCAT UHF radar in the morning sector (04:40–05:25 MLT. The precipitation develops as quasi-periodic pulses with a period of about 100 s. We discuss the models of pulsating precipitation due to the whistler cyclotron instability and show that our observations can be explained by such a model.

  11. What Counts as "Truth" -- Reason Versus Emotion in Vaccine Decision Making

    Science.gov (United States)

    Mnookin, S.

    2014-12-01

    Vaccines are without question one of the most successful public health interventions the world has ever known. Despite this, for the past decade-and-a-half, industrialized countries around the world, from the United States to Germany and from Australia to Israel, have been confronted with specious panics about vaccine safety and efficacy, many of which center around claims that vaccines can cause autism. These fears can be traced to two events: a since-retracted paper published by a disgraced gastroenterologist claiming the measles-mumps-rubella vaccine was linked to a gut disease which, in turn, was linked to autism; and the United States's decision to remove a mercury-based preservative called thimerosal from standard pediatric vaccines in the late 1990s. The effects of these scares are being felt worldwide. Each year for the past several years, the US has had more measles outbreaks than at any time since the mid-1990s, a fact which is especially frightening given that the WHO declared measles eliminated from North America in 2000. In France, a nationwide measles outbreak has caused thousands of hospitalizations and a number of deaths. I will address several issues central to this topic: Given the overwhelming amount of evidence showing vaccines are safe and the total lack of evidence showing they cause autism, why do these fears persist, and what can be done to combat them? Has the public health establishment's response to these fears been sufficient? To what extent do concerns about vaccines function as proxies for more opaque concerns regarding modern-day health care? And finally, what is the effect of a lack of evidence-based research on the best way to combat misinformation?

  12. Reasons for choosing dentistry as a career: a study involving male and female first-year students in Peru.

    Science.gov (United States)

    Bernabé, E; Icaza, J L; Delgado-Angulo, E K

    2006-11-01

    The aim of this study was to compare the reported reasons to choose dentistry as a career between Peruvian male and female first-year students. A self-completion questionnaire was administered to 75 first-year students registered at the Faculty of Dentistry of the Universidad Peruana Cayetano Heredia, Lima, Peru. The questionnaire comprised 16 items grouped into four categories (economic, professional, vocational and personal background). Students rated the importance of each item for selecting dentistry as a career on a Likert-type scale of five points. The Mann-Whitney test was used to compare groups and item scores by gender. A male/female proportion of 1/2.1 was found in the pool of participating students. When group and item scores were compared between genders, statistically significant differences were only found for vocational and personal background reasons (P < 0.05); however, the three reasons that obtained higher scores for each gender were found to be different. It is recommended that further studies be conducted to increase the sample, by extending the study and evaluating not only reasons for choosing dentistry, but also other factors that may influence the decision. PMID:17038016

  13. Radiation dosage during pediatric diagnostic or interventional cardiac catheterizations using the "air gap technique" and an aggressive "as low as reasonably achievable" radiation reduction protocol in patients weighing < 20 kg

    Directory of Open Access Journals (Sweden)

    Frank A Osei

    2016-01-01

    Results: One-hundred and twenty-seven patients underwent 151 procedures within the study period. The median age was 1.2 years (range: 1 day to 7.9 years and median weight was 8.8 kg (range: 1.9-19.7. Eighty-nine (59% of the procedures were interventional. The median total fluoro time was 13 min [interquartile range (IQR 7.3-21.8]. The median total air Kerma (K product was 55.6 mGy (IQR 17.6-94.2 and dose area product (DAP was 189 Gym2 (IQR 62.6-425.5. Conclusion: Use of a novel ALARA and AGT protocol for cardiac catheterizations in children markedly reduced radiation exposure to levels far below recently reported values.

  14. Socio-Economic Background and Access to Internet as Correlates of Students' Achievement in Agricultural Science

    Science.gov (United States)

    Adegoke, Sunday Paul; Osokoya, Modupe M.

    2015-01-01

    This study investigated access to internet and socio-economic background as correlates of students' achievement in Agricultural Science among selected Senior Secondary Schools Two Students in Ogbomoso South and North Local Government Areas. The study adopted multi-stage sampling technique. Simple random sampling was used to select 30 students from…

  15. Attitude and Motivation as Predictors of Academic Achievement of Students in Clothing and Textiles

    Science.gov (United States)

    Uwameiye, B. E.; Osho, L. E.

    2011-01-01

    This study investigated attitude and motivation as predictors of academic achievement of students in clothing and textiles. Three colleges of education in Edo and Delta States were randomly selected for use in this study. From each school, 40 students were selected from Year III using simple random technique yielding a total of 240 students. The…

  16. Self-Efficacy, Goal Orientations and Learning Strategies as Mediators between Preceding and Subsequent Academic Achievement

    Science.gov (United States)

    Diseth, Age

    2011-01-01

    High school grade point average (HSGPA), self-efficacy, goal orientations, learning strategies, and examination grade were measured in a sample of Norwegian undergraduate psychology students in order to investigate motives and strategies as mediators between preceding and subsequent academic achievement. Correlation analysis showed strong…

  17. Emotional Intelligence and Gender as Predictors of Academic Achievement among Some University Students in Barbados

    Science.gov (United States)

    Fayombo, Grace A.

    2012-01-01

    This study investigated emotional intelligence (attending to emotion, positive expressivity and negative expressivity) and gender as predictors of academic achievement among 163 undergraduate psychology students in The University of the West Indies (UWI), Cave Hill Campus, Barbados. Results revealed significant positive and negative correlations…

  18. Student-Related Variables as Predictors of Academic Achievement among Some Undergraduate Psychology Students in Barbados

    Science.gov (United States)

    Fayombo, Grace Adebisi

    2011-01-01

    This study examined some student-related variables (interest in higher education, psychological resilience and study habit) as predictors of academic achievement among 131 (M (mean) = 28.17, SD (standard deviation) = 1.61) first year psychology students in the Introduction to Developmental Psychology class in UWI (The University of the West…

  19. Trajectories of Career Aspirations through Adolescence and Young Adulthood: Early Math Achievement as a Critical Filter

    Science.gov (United States)

    Shapka, Jennifer D.; Domene, Jose F.; Keating, Daniel P.

    2006-01-01

    Growth curve modelling was used to trace the trajectory of the prestige dimension of career aspirations from Grade 9 through to 3 years after high school, as a function of gender and early high school math achievement. The sample consisted of 218 university-bound adolescents (129 female, 89 male). Initial aspiration levels, the slope, and the…

  20. Institutional Factors as Predictors of Students' Academic Achievement in Colleges of Education in South Western Nigeria

    Science.gov (United States)

    Adeyemi, Abisola Moradeyo; Adeyemi, Seminu Babatunde

    2014-01-01

    The enhancement of the academic achievement of the Nigerian students has continued to engage the attention of educational practitioners and policy makers. This paper investigated institutional factors as predictors of students' academic performance in Colleges of Education in South-Western Nigeria. The study employed the ex post facto design using…

  1. The Effect of Family Processes on School Achievement as Moderated by Socioeconomic Context

    Science.gov (United States)

    Oxford, Monica L.; Lee, Jungeun Olivia

    2011-01-01

    This longitudinal study examined a model of early school achievement in reading and math, as it varies by socioeconomic context, using data from the NICHD Study of Early Child Care and Youth Development. A conceptual model was tested that included features of family stress, early parenting, and school readiness, through both a single-group…

  2. Time Perspective and School Membership as Correlates to Academic Achievement among African American Adolescents

    Science.gov (United States)

    Adelabu, Detris Honora

    2007-01-01

    This study examined the relationship of academic achievement to time perspective (future, present) and school membership (belonging, acceptance, rejection) among 232 low-income, urban African American adolescents. Findings indicated positive, significant relationships among academic achievement, future time perspective, school belonging, and…

  3. Performance-Based Pay as a Motivational Tool for Achieving Organisational Performance: An Exploratory Case Study

    OpenAIRE

    Francis Boachie-Mensah; Ophelia Delali Dogbe

    2011-01-01

    The issue of employees’ performance in furtherance of organisational objectives has occupied managementattention for long. Differences in levels of performance have been attributed to differences in skills and abilitieson the one hand, and to different theories of money on the other. This study examined the issue ofperformance-based pay as a motivational tool for achieving organisational performance, using the situation in amanufacturing company in Ghana as a case study. The main objective of...

  4. A STUDY OF ADOLESCENTS’ ANXIETY AND ACHIEVEMENT IN ENGLISH AS A FOREIGN LANGUAGE

    OpenAIRE

    Ridha Fadillah

    2011-01-01

    This paper aims at investigating whether there is relationship between students’ anxiety and students’ achievement in English as a foreign language among adolescents at Sekolah Menengah Umum Negeri 1 Banjarbaru, South Kalimantan. The sample was 152 students of sixteen and seventeen years old at second grade. The results indicate that the students’ anxiety in learning English as foreign language is at moderate level. There is no significant relationship between English language anxiety and stu...

  5. A Phenomenological Investigation of Student Achievement: Perceptions of Academic Success as Told by Single African American and Hispanic Mothers

    Science.gov (United States)

    Stewart, Shawn M.

    2010-01-01

    A number of factors seem to contribute to low student achievement in the organization of education. Some of these factors exist prior to children reaching school age. It seems as though a vast quantity of minority students struggle academically. Research supports the belief that socioeconomic status, ethnicity, and single-parent families have an…

  6. Theory of Mind as a Mediator of Reasoning and Facial Emotion Recognition: Findings from 200 Healthy People

    OpenAIRE

    Lee, Seul Bee; Koo, Se Jun; Song, Yun Young; Lee, Mi Kyung; JEONG, YU-JIN; Kwon, Catherine; Park, Kyoung Ri; Park, Jin Young; Kang, Jee In; Lee, Eun; An, Suk Kyoon

    2013-01-01

    Objective It was proposed that the ability to recognize facial emotions is closely related to complex neurocognitive processes and/or skills related to theory of mind (ToM). This study examines whether ToM skills mediate the relationship between higher neurocognitive functions, such as reasoning ability, and facial emotion recognition. Methods A total of 200 healthy subjects (101 males, 99 females) were recruited. Facial emotion recognition was measured through the use of 64 facial emotional ...

  7. Multiple metal accumulation as a factor in learning achievement within various New Orleans elementary school communities

    International Nuclear Information System (INIS)

    In New Orleans, the elementary school system is divided into attendance districts with established boundaries that define student enrollment among schools. This study concerns environmental quality as defined by amount of soil metals (Pb, Zn, Cd, Ni, Mn, Cu, Co, Cr, and V) in attendance district elementary school communities (n=111) paired with learning achievement as measured by individual test scores (n=32,741) of students enrolled at each school. The Louisiana Educational Assessment Program (LEAP) 4th grade scores measure learning achievement for English language arts, social studies, mathematics, and science. The best fit between environmental quality and higher learning achievement is found to be inversely associated with the sum of the metals or multiple metal accumulations (MMA) in New Orleans communities. The P values for MMA partitions for ELA, SOC, MAT, and SCI are 0.57x10-7, 0.29x10-8, 0.41x10-6, and 0.17x10-8, respectively. Efforts to prevent childhood metal exposure should improve New Orleanians' learning achievement as measured by the LEAP scores and thereby enhance the socioeconomic situation in contaminated communities. This study establishes global relationships between LEAP scores in schools and soil metal concentrations in school neighborhoods. However, these data do not allow relating of the LEAP scores with metal levels for individual students

  8. Reasons for Low Levels of Interactivity

    DEFF Research Database (Denmark)

    Etter, Michael

    2013-01-01

    The interactivity levels of online CSR communication are typically low. This study explores the reasons for the low levels of interactivity in the popular social media tool Twitter. An analysis of 41,864 Twitter messages (tweets) from the thirty most central corporate accounts in a CSR Twitter...

  9. The -Younger-Minority Boy" as a Clue to the Source of Achievement Orientation.

    Science.gov (United States)

    Kammeyer, Kenneth C. W.

    This study is a follow-up of the work by Morris Rosenberg who found that younger-minority boys tend to have high self-esteem, but a relatively low achievement orientation and low grades in school. Sampling a total 898 high school senior boys, this study found that younger minority boys do have lower grades and lower occupational and educational…

  10. The theory of reasoned action as parallel constraint satisfaction: towards a dynamic computational model of health behavior.

    Science.gov (United States)

    Orr, Mark G; Thrush, Roxanne; Plaut, David C

    2013-01-01

    The reasoned action approach, although ubiquitous in health behavior theory (e.g., Theory of Reasoned Action/Planned Behavior), does not adequately address two key dynamical aspects of health behavior: learning and the effect of immediate social context (i.e., social influence). To remedy this, we put forth a computational implementation of the Theory of Reasoned Action (TRA) using artificial-neural networks. Our model re-conceptualized behavioral intention as arising from a dynamic constraint satisfaction mechanism among a set of beliefs. In two simulations, we show that constraint satisfaction can simultaneously incorporate the effects of past experience (via learning) with the effects of immediate social context to yield behavioral intention, i.e., intention is dynamically constructed from both an individual's pre-existing belief structure and the beliefs of others in the individual's social context. In a third simulation, we illustrate the predictive ability of the model with respect to empirically derived behavioral intention. As the first known computational model of health behavior, it represents a significant advance in theory towards understanding the dynamics of health behavior. Furthermore, our approach may inform the development of population-level agent-based models of health behavior that aim to incorporate psychological theory into models of population dynamics. PMID:23671603

  11. The theory of reasoned action as parallel constraint satisfaction: towards a dynamic computational model of health behavior.

    Directory of Open Access Journals (Sweden)

    Mark G Orr

    Full Text Available The reasoned action approach, although ubiquitous in health behavior theory (e.g., Theory of Reasoned Action/Planned Behavior, does not adequately address two key dynamical aspects of health behavior: learning and the effect of immediate social context (i.e., social influence. To remedy this, we put forth a computational implementation of the Theory of Reasoned Action (TRA using artificial-neural networks. Our model re-conceptualized behavioral intention as arising from a dynamic constraint satisfaction mechanism among a set of beliefs. In two simulations, we show that constraint satisfaction can simultaneously incorporate the effects of past experience (via learning with the effects of immediate social context to yield behavioral intention, i.e., intention is dynamically constructed from both an individual's pre-existing belief structure and the beliefs of others in the individual's social context. In a third simulation, we illustrate the predictive ability of the model with respect to empirically derived behavioral intention. As the first known computational model of health behavior, it represents a significant advance in theory towards understanding the dynamics of health behavior. Furthermore, our approach may inform the development of population-level agent-based models of health behavior that aim to incorporate psychological theory into models of population dynamics.

  12. Spatial ability, motivation, and attitude of students as related to science achievement

    Science.gov (United States)

    Bolen, Judy Ann

    Understanding student achievement in science is important as there is an increasing reliance of the U.S. economy on math-, science-, and technology-related fields despite the declining number of youth seeking college degrees and careers in math and science. A series of structural equation models were tested using the scores from a statewide science exam for 276 students from a suburban north Texas public school district at the end of their 5th grade year and the latent variables of spatial ability, motivation to learn science and science-related attitude. Spatial ability was tested as a mediating variable on motivation and attitude; however, while spatial ability had statistically significant regression coefficients with motivation and attitude, spatial ability was found to be the sole statistically significant predictor of science achievement for these students explaining 23.1% of the variance in science scores.

  13. Student motivation and achievement in learning English as a second language using Second Life

    OpenAIRE

    Tosti H. C. Chiang; Stephen J.H. Yang; Chester S. J. Huang; Hsin-Hun Liou

    2014-01-01

    This study investigates the impact of a 3D virtual learning environment based on Second Life on student motivation and achievement in learning English as a second language. Twenty-one university students participate in this study, with the support of an English instructor. The Motivated Strategies for Learning Questionnaire (MSLQ) was used to evaluate students’ intrinsic and extrinsic goal orientation and self-efficacy in Second Life. The pre-test and post-test were used to assess students’ l...

  14. Recent achievements on annular Josephson structures and their application as radiation detectors

    International Nuclear Information System (INIS)

    One of the stimulating area of superconductors investigations lies in the achieved and potential applications as radiation detectors. Results concerning annular Josephson junctions in this context are discussed. Fundamental aspects, mainly related to the fluxon dynamics in such structures, are discussed in detail. The results confirm the importance of the precious sharing of technological requests with fundamental physical implications. Peculiar results are reported dealing with new resonances occurring on these Josephson junctions of annular configuration

  15. Competency-based assignments as a means of achieving modern educational outcomes

    OpenAIRE

    Olga Korshunova

    2016-01-01

    Based on the analysis of the transition state of the educational sphere from one educational paradigm to the other one, the article discusses the problem of interrelation of key competencies and universal learning performances as the intended learning outcomes. Transformation of the main function of the education content from the purpose of learning to the means of achieving new educational outcomes is emphasized. The concept "activity-based learning unit" is revealed on the example of compet...

  16. A Portfolio as an Alternative Means of Presenting the University Student’s Achievements

    OpenAIRE

    Regina Gennadyevna Sakhieva; Suriya Irekovna Gilmanshina; Iskander Rafailevich Gilmanshin; Svetlana Sergeyevna Kosmodemyanskaya; Ilsia Rafailevna Akchurina; Rimma Nadyrovna Sagitova

    2014-01-01

    The article defines the objective, the tasks, the functions of the portfolio as an alternative means of presentationof the students’ achievements in higher professional school. Nowadays there is no specified structure of thestudent portfolio, it may vary according to the targets, direction, educational profile and other factors. The paperconsiders the development of the structure of the undergraduate student portfolio. It also describes the principlesof designing a portfolio, the main advanta...

  17. The Effect of Family Processes on School Achievement as Moderated by Socioeconomic Context

    OpenAIRE

    Oxford, Monica L.; Lee, Jungeun Olivia

    2011-01-01

    This longitudinal study examined a model of early school achievement in reading and math, as it varies by socioeconomic context, using data from the NICHD Study of Early Child Care and Youth Development. A conceptual model was tested that included features of family stress, early parenting, and school readiness, through both a single-group analysis and also a multiple-group analysis. Latent profile analysis was used to identify subgroups of more advantaged and less advantaged families. Family...

  18. Strengthening Safety Culture as an Overriding Priority, in Achieving Global Nuclear Security Approach

    International Nuclear Information System (INIS)

    In the IAEA glossary safety culture is defined as the assembly of characteristics and attitudes in organizations and individuals, which establishes that, as an overriding priority, protection and safety issues receive the attention warranted by their significance. It has been observed that a safety culture, as a part of both security and safety, possesses a few obstacles that should be noticed: safety culture cannot be directly regulated; variation in national cultures means that what constitutes as a good approach to enhancing safety culture in one country may not be the best approach in another. Three stages have been identified in developing and strengthening safety culture: 1 A technical issue (rules and regulations)/ first stage 2 Good safety performance (primarily in terms of safety targets or goals)/ second stage 3 A continuing process of improvement to which everyone can contribute/ third stage There are several key issues in safety culture, such as: a commitment, use of procedures, a conservative decision making (STAR) a reporting culture. Organizations and individuals should have attention on these. Overall common goals are to achieve and maintain a high level of safety and security of radioactive sources as well as facilities. Measures that are concerned on safeguards restrict access to the radioactive sources, conditioning and/or recycling of sources, and systems for detection the passage of the radioactive sources at strategic points, have gained main support. The main partners in implementation these measures are: IAEA, USA, Russian Federation, G8- Global Partnership, and European Union The member states of the IAEA have at their disposal internationally agreed standards. Current differences in applying standards in the IAEA member states are mainly related to state preparedness to cope with demands. Developing and less developed countries with small and medium nuclear programmes have difficulties to accept rules and regulations, to establish

  19. When will is not the same as should: The role of modals in reasoning with legal conditionals.

    Science.gov (United States)

    Gazzo Castañeda, Lupita Estefania; Knauff, Markus

    2016-01-01

    Naïve reasoners reject logically valid conclusions from conditional rules if they can think of exceptions in which the antecedent is true, but the consequent is not. However, when reasoning with legal conditionals (e.g., "If a person kills another human, then this person should be punished for manslaughter") people hardly consider exceptions but evaluate conclusions depending on their own sense of justice. We show that participants' reluctance to consider exceptions in legal reasoning depends on the modal auxiliary used. In two experiments we phrased legal conditionals either with the modal "should" (i.e., " . . . then this person should be punished"), or with "will" (i.e., " . . . then this person will be punished") and presented them as modus ponens or modus tollens inferences. Participants had to decide whether the offender should or will be punished (modus ponens) or whether the offender indeed committed the offence (modus tollens). For modus ponens inferences phrased with "should" we replicate previous findings showing that participants select conclusions on the basis of their own sense of justice (Experiments 1 and 2). Yet, when the legal conditional is phrased with the modal "will" this effect is attenuated (Experiments 1 and 2), and exceptions are considered (Experiment 1). The modal auxiliary did not affect modus tollens inferences. PMID:26292145

  20. Low and high achievers in math

    DEFF Research Database (Denmark)

    Overgaard, Steffen; Tonnesen, Pia Beck; Weng, Peter;

    2015-01-01

    In this session we will present the results of the preliminary analysis of the qualitative and quantitative data, which can be used to enhance the teaching of low and high mathematics achievers so as to increase their mathematical knowledge and confidence....

  1. Case-Based Reasoning as a Heuristic Selector in a Hyper-Heuristic for Course Timetabling Problems

    OpenAIRE

    Petrovic, Sanja; Qu, Rong

    2002-01-01

    This paper studies Knowledge Discovery (KD) using Tabu Search and Hill Climbing within Case-Based Reasoning (CBR) as a hyper-heuristic method for course timetabling problems. The aim of the hyper-heuristic is to choose the best heuristic(s) for given timetabling problems according to the knowledge stored in the case base. KD in CBR is a 2-stage iterative process on both case representation and the case base. Experimental results are analysed and related research issues for future work are dis...

  2. Spatial Visualization as Mediating between Mathematics Learning Strategy and Mathematics Achievement among 8th Grade Students

    Science.gov (United States)

    Rabab'h, Belal; Veloo, Arsaythamby

    2015-01-01

    Jordanian 8th grade students revealed low achievement in mathematics through four periods (1999, 2003, 2007 & 2011) of Trends in International Mathematics and Science Study (TIMSS). This study aimed to determine whether spatial visualization mediates the affect of Mathematics Learning Strategies (MLS) factors namely mathematics attitude,…

  3. The design and implementation of an Interactive Computerised Decision Support Framework (ICDSF) as a strategy to improve nursing students' clinical reasoning skills.

    Science.gov (United States)

    Hoffman, Kerry; Dempsey, Jennifer; Levett-Jones, Tracy; Noble, Danielle; Hickey, Noelene; Jeong, Sarah; Hunter, Sharyn; Norton, Carol

    2011-08-01

    This paper describes the conceptual design and testing of an Interactive Computerised Decision Support Framework (ICDSF) which was constructed to enable student nurses to "think like a nurse." The ICDSF was based on a model of clinical reasoning. Teaching student nurses to reason clinically is important as poor clinical reasoning skills can lead to "failure-to rescue" of deteriorating patients. The framework of the ICDSF was based on nursing concepts to encourage deep learning and transferability of knowledge. The principles of active student participation, situated cognition to solve problems, authenticity, and cognitive rehearsal were used to develop the ICDSF. The ICDSF was designed in such a way that students moved through it in a step-wise fashion and were required to achieve competency at each step before proceeding to the next. The quality of the ICDSF was evaluated using a questionairre survey, students' written comments and student assessment measures on a pilot and the ICDSF. Overall students were highly satisfied with the clinical scenarios of the ICDSF and believed they were an interesting and useful way to engage in authentic clinical learning. They also believed the ICDSF was useful in developing cognitive skills such as clinical reasoning, problem-solving and decision-making. Some reported issues were the need for good technical support and the lack of face to face contact when using e-learning. Some students also believed the ICDSF was less useful than actual clinical placements. PMID:21074299

  4. Italy as the Cradle of the Renaissance:From the Perspective of Its Partic-ular Reasons

    Institute of Scientific and Technical Information of China (English)

    HUANG Mei

    2015-01-01

    The Renaissance is a period from the 14th to the 17th centuries, considered as a shift from Middle Ages to Modern times of European history. It developed from Middle Ages which laid its political, economical, cultural and social foundation. Owing to the development of capitalist production relations in Europe during the late Middle Ages, bourgeoisie initiated this cultural movement whose essence is humanism as a fight against feudalism.The Renaissance originated in the form of a cultural movement from Italy in the 14th century and swept over the whole Europe. Apart from the common factors contributing to this movement, the peculiar reasons why Italy became the bellwether of this essential cultural movement are as follows:direct inherit of ancient Roman tradi⁃tion, the favorable geographical position, the unparalleled cities with the development of commerce, city republics and secularism.

  5. Site controlled InAs quantum dots with ultra low densities and improved spectral uniformity

    International Nuclear Information System (INIS)

    In order to exploit InAs Quantum Dots (QDs) coupled to microcavities as single photon sources in a scalable manner one needs to know the exact position of the QD for device alignment. To improve the yield of spectrally resonant devices without adjusting the resonator geometry to the individual QD emission wavelength it is necessary to reduce spectral inhomogeneities in the ensemble emission of the QD array. The position control of our site controlled QDs (SCQDs) is maintained by directing the QD nucleation to shallow etched nanoholes on a (1,0,0)GaAs surface. To achieve a reasonably low single QD linewidth and ensemble broadening, growth parameters during the molecular beam epitaxy (MBE) deposition step of the QDs have been optimized and investigated. We have monitored the influence of the substrate temperature during SCQD growth as an important parameter for spectral homogeneity and achieved accurate QD nucleation of single SCQDs on pitches up to 4 μm on both uncapped and buried SCQDs.

  6. First-person authority and Self-Knowledge as an Achievement

    OpenAIRE

    Corbí, Josep E.

    2009-01-01

    There is much that I admire in Richard Moran¿s account of how first- person authority may be consistent with self-knowledge as an achievement. In this paper, I examine his attempt to characterize the goal of psychoanalytic treatment, which is surely that the patient should go beyond the mere theoretical acceptance of the analyst¿s interpretation, and requires instead a more intimate, first-personal, awareness by the patient of their psychological condition. I object, however, that the way in ...

  7. Intrinsic and extrinsic motivation as predictors of work effort: the moderating role of achievement goals.

    Science.gov (United States)

    Dysvik, Anders; Kuvaas, Bård

    2013-09-01

    This research explored the roles of intrinsic motivation (IM) and extrinsic motivation (EM) and the 2 × 2 model of achievement goals as predictors of increased work effort (WE). A cross-lagged field study was conducted among 1,441 employees from three large Norwegian service organizations across a 10-month time span. The results showed that the relationship between IM and increased WE was more positive for employees with high levels of mastery-approach goals. This observation suggests that having congruent goals may accentuate the positive relationship between IM and WE. PMID:22273179

  8. Meningoradiculitis due to borreliosis presenting as low back pain only

    International Nuclear Information System (INIS)

    We report a child with Borrelia burgdorferi meningoradiculitis. This entity, also known as Bannwarth syndrome, is rare and its presentation with low back pain only is even more unusual. The MRI findings can suggest the diagnosis. (orig.)

  9. Racial-ethnic identity in mid-adolescence: content and change as predictors of academic achievement.

    Science.gov (United States)

    Altschul, Inna; Oyserman, Daphna; Bybee, Deborah

    2006-01-01

    Three aspects of racial-ethnic identity (REI)-feeling connected to one's racial-ethnic group (Connectedness), being aware that others may not value the in-group (Awareness of Racism), and feeling that one's in-group is characterized by academic attainment (Embedded Achievement)-were hypothesized to promote academic achievement. Youth randomly selected from 3 low-income, urban schools (n=98 African American, n=41 Latino) reported on their REI 4 times over 2 school years. Hierarchical linear modeling shows a small increase in REI and the predicted REI-grades relationship. Youth high in both REI Connectedness and Embedded Achievement attained better grade point average (GPA) at each point in time; youth high in REI Connectedness and Awareness of Racism at the beginning of 8th grade attained better GPA through 9th grade. Effects are not moderated by race-ethnicity. PMID:16999790

  10. Low Density Self-Assembled InAs/GaAs Quantum Dots Grown by Metal Organic Chemical Vapour Deposition

    Institute of Scientific and Technical Information of China (English)

    LI Lin; LIU Guo-Jun; WANG Xiao-Hua; LI Mei; LI Zhan-Guo; WAN Chun-Ming

    2008-01-01

    The serf-assembled InAs quantum dots (QDs) on GaAs substrates with low density (5×108cm-2) are achieved using relatively higher growth temperature and low InAs coverage by low-pressure metal-organic chemical vapour deposition.The macro-PL spectra exhibit three emission peaks at 1361,1280 and 1204nm,corresponding to the ground level (GS),the first excited state (ES1) and the second excited state (ES2) of the QDs,respectively,which are obtained when the GaAs capping layer/s grown using triethylgallium and tertiallybutylarsine.As a result of micro-PL,only a few peaks from individual dots have been observed.The exciton-biexciton behaviour was clearly observed at low temperature.

  11. Corporate Governance as a Crucial Factor in Achieving Sustainable Corporate Performance

    Directory of Open Access Journals (Sweden)

    Julija Bistrova

    2014-06-01

    Full Text Available In the developed stock markets the corporate governance aspect is crucial in the stock portfolio selection process for investor seeking to achieve shareholder value sustainability. In the emerging markets the importance of the corporate governance role just starts to be realized by the investors and by the corporate managers. The present research, looking at the stock performance leaders and laggards, analyzes whether the corporate governance system matters to achieve long-term shareholder value within the Central and Eastern European stock markets universe. Corporate governance quality was assessed and compared among the out- and underperformers. The financial results plausibility and the ownership structure were considered as well. Additionally, the authors analyzed whether the quality of corporate governance influences the economic performance of the company. The obtained results provide the proof that the corporate governance does matter as the market outperformers have above average corporate governance quality and provide trustworthy financial results more often than the underperforming companies. Besides, well-governed companies are also able to deliver more attractive financial results.

  12. The importance of safety in achieving the widespread use of hydrogen as a fuel

    Energy Technology Data Exchange (ETDEWEB)

    Edeskuty, F.J.

    1997-09-01

    The advantages of hydrogen fuel have been adequately demonstrated on numerous occasions. However, two major disadvantages have prevented any significant amount of corresponding development. These disadvantages have been in the economics of producing sufficient quantities of hydrogen and in the safety (both real and perceived) of its use. To date work has mostly been properly centered on solving the economic problems. However, a greater effort on the safety of new hydrogen systems now being proposed also deserves consideration. To achieve the greatest safety in the expansion of the use of hydrogen into its wide-spread use as a fuel, attention must be given to four considerations. These are, obtaining knowledge of all the physical principles involved in the new uses, having in place the regulations that allow the safe interfacing of the new systems, designing and constructing the new systems with safety in mind, and the training of the large number of people that will become the handlers of the hydrogen. Existing organizations that produce, transport, or use hydrogen on a large scale have an excellent safety record. This safety record comes as a consequence of dedicated attention to the above-mentioned principles. However, where these principles were not closely followed, accidents have resulted. Some examples can be cited. As the use of hydrogen becomes more widespread, there must be a mechanism for assuring the universal application of these principles. Larger and more numerous fleet operations with hydrogen fuel may be the best way to begin the indoctrination of the general public to the more general use of hydrogen fuel. Demonstrated safe operation with hydrogen is vital to its final acceptance as the fuel of choice.

  13. Achieving 90–90–90 in paediatric HIV: adolescence as the touchstone for transition success

    Directory of Open Access Journals (Sweden)

    Sonia Lee

    2015-12-01

    Full Text Available Introduction: The number of children less than 15 years estimated to be living with HIV globally approximated 3.2 million in 2013. Young people aged 15 to 24 years living with HIV approximated 4 million. The survival of these children and adolescents into adulthood poses new and urgent challenges of transition from the paediatric to adolescent to adult healthcare settings due to emerging developmental, psychosocial and comorbid issues. In order to achieve treatment targets of 90–90–90 across the continuum of care for paediatric HIV by 2020, focused efforts on the implementation of appropriate healthcare transition plans across the lifespan, with a focus on adolescence, should be prioritized. Discussion: Published data or empirical evidence examining implementation of transition models and association with clinical outcomes are limited. While some guidelines do exist that offer recommendations about how to promote seamless transitions, very few data are available to assess the adequacy of these guidelines and whether they are effectively adhered to in clinical care settings globally. Furthermore, paediatric and adolescent HIV infection, either acquired perinatally or behaviourally, is set apart from other chronic illnesses as a highly stigmatizing disease that disproportionately affects poor, minority and often marginalized populations. Focused efforts on adolescence as the touchstone for transition practices and policies need to be implemented. Conclusions: Optimal healthcare for these vulnerable populations, particularly in resource-limited settings, will require HIV-specific transitional care services and programmes that are coordinated, collaborative, integrated and, importantly, evidence-based.

  14. Low Test Anxiety as a Potential Indicator of Underachievement

    Science.gov (United States)

    Wittmaier, Bruce C.

    1976-01-01

    Compared with high-test anxious students, those with low scores on both scales of the Achievement Anxiety Test were less anxious before a test, studied less for it, and got more sleep the night before. The pattern of results was congruent with expectations. (Author)

  15. Facilitating progress in health behaviour theory development and modification: the reasoned action approach as a case study.

    Science.gov (United States)

    Head, Katharine J; Noar, Seth M

    2014-01-01

    This paper explores the question: what are barriers to health behaviour theory development and modification, and what potential solutions can be proposed? Using the reasoned action approach (RAA) as a case study, four areas of theory development were examined: (1) the theoretical domain of a theory; (2) tension between generalisability and utility, (3) criteria for adding/removing variables in a theory, and (4) organisational tracking of theoretical developments and formal changes to theory. Based on a discussion of these four issues, recommendations for theory development are presented, including: (1) the theoretical domain for theories such as RAA should be clarified; (2) when there is tension between generalisability and utility, utility should be given preference given the applied nature of the health behaviour field; (3) variables should be formally removed/amended/added to a theory based on their performance across multiple studies and (4) organisations and researchers with a stake in particular health areas may be best suited for tracking the literature on behaviour-specific theories and making refinements to theory, based on a consensus approach. Overall, enhancing research in this area can provide important insights for more accurately understanding health behaviours and thus producing work that leads to more effective health behaviour change interventions. PMID:25053006

  16. Meningoradiculitis due to borreliosis presenting as low back pain only

    Energy Technology Data Exchange (ETDEWEB)

    Demaerel, P.; Crevits, I.; Baert, A.L. [Department of Radiology, University Hospitals, Leuven (Belgium); Casteels-Van Daele, M. [Department of Paediatrics, University Hospitals, Leuven (Belgium)

    1998-02-01

    We report a child with Borrelia burgdorferi meningoradiculitis. This entity, also known as Bannwarth syndrome, is rare and its presentation with low back pain only is even more unusual. The MRI findings can suggest the diagnosis. (orig.) With 1 fig., 3 refs.

  17. The ground state properties of In(Ga)As/GaAs low strain quantum dots

    Science.gov (United States)

    Pieczarka, Maciej; Sęk, Grzegorz

    2016-08-01

    We present theoretical studies on the confined states in low-strain In(Ga)As quantum dots (QDs). The 8-band k·p model together with the continuum elasticity theory and piezoelectric fields were employed to calculate the potential and confined electron and hole eigenstates. We focused on low-indium-content QDs with distinct in-plane asymmetry, which are naturally formed in the low strain regime of the Stranski-Krastanow growth mode. It has been found that the naturally thick wetting layer together with piezoelectric potential affect the total confinement potential to such extent that the hole eigenstates can get the spatial in-plane orientation orthogonal to the main axis of the dot elongation. This can influence both, qualitatively and quantitatively, many of the electronic and optical properties, as e.g. the polarization selection rules for the optical transition or the transitions oscillator strength. Eventually, importance of the degree of the shape asymmetry or the dots' size, and differences between the low-strain (low-In-content) QDs and pure InAs dots formed in high strain conditions are discussed.

  18. Use of talc as low-cost clarifier for wastewater.

    Science.gov (United States)

    Grafia, Ana L; Castillo, Luciana A; Barbosa, Silvia E

    2014-01-01

    Talc is proposed as a low-cost mineral for wastewater clarification. In this sense, adsorption of methylene blue (MB) from aqueous solutions was studied comparatively by using sepiolite (qualified as very good adsorbent) and two talc samples with different particle size and purity degree. The MB adsorption was assessed by determining remnant dye in the supernatant using UV-vis spectroscopy and by detecting dye adsorbed on mineral samples through thermogravimetric analysis and infrared spectroscopy. Both isothermal curves and kinetic studies demonstrate that talc is a good dye adsorbent. Particularly, with dye concentrations similar to those of textile wastewater, talc was demonstrated to adsorb the same dye content of sepiolite at similar times. Natural talc could be employed as a low-cost alternative in wastewater treatment for the removal of cationic dyes. PMID:24552739

  19. The theory of Realistic Mathematics Education as a theoretical framework for teaching low attainers in mathematics

    OpenAIRE

    Hayley Barnes

    2005-01-01

    This article recounts the process embarked on and reasons for selecting the theory of Realistic Mathematics Education (RME) as the theoretical framework in a study carried out with low attaining learners. In the study an intervention for low attaining grade 8 mathematics learners was implemented in an attempt to improve the understanding of the participants with regard to place value, fractions and decimals, and to identify characteristics of this type of intervention and potential design pr...

  20. The theory of Realistic Mathematics Education as a theoretical framework for teaching low attainers in mathematics

    OpenAIRE

    Hayley Barnes

    2011-01-01

    This article recounts the process embarked on and reasons for selecting the theory of Realistic Mathematics Education (RME) as the theoretical framework in a study carried out with low attaining learners. In the study an intervention for low attaining grade 8 mathematics learners was implemented in an attempt to improve the understanding of the participants with regard to place value, fractions and decimals, and to identify characteristics of this type of intervention and potential design pri...

  1. Clinical examination findings as prognostic factors in low back pain

    DEFF Research Database (Denmark)

    Hartvigsen, Lisbeth; Kongsted, Alice; Hestbaek, Lise

    2015-01-01

    BACKGROUND: There is a strong tradition of performing a clinical examination of low back pain (LBP) patients and this is generally recommended in guidelines. However, establishing a pathoanatomic diagnosis does not seem possible in most LBP patients and clinical tests may potentially be more...... relevant as prognostic factors. The aim of this review of the literature was to systematically assess the association between low-tech clinical tests commonly used in adult patients with acute, recurrent or chronic LBP and short- and long-term outcome. METHODS: MEDLINE, Embase, and MANTIS were searched...... from inception to June 2012. Prospective clinical studies of adult patients with LBP with or without leg pain and/or signs of nerve root involvement or spinal stenosis, receiving non-surgical or no treatment, which investigated the association between low-tech clinical tests and outcome were included...

  2. Defect studies in low-temperature-grown GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Bliss, D.E.

    1992-11-01

    High content of excess As is incorporated in GaAs grown by low-temperature molecular-beam-epitaxy (LTMBE). The excess As exists primarily as As antisite defects AsGa and a lesser extent of gallium vacancies V[sub Ga]. The neutral AsGa-related defects were measured by infrared absorption at 1[mu]m. Gallium vacancies, V[sub Ga], was investigated by slow positron annihilation. Dependence of defect contents on doping was studied by Si and Be dopants. No free carriers are generated by n-type or p-type doping up to 10[sup 19] cm[sup [minus]3] Si or Be. Raman data indicate Be occupies Ga substitutional sites but Si atom is not substitutional. Si induces more As[sub Ga] in the layer. As As[sub Ga] increases, photoquenchable As[sub Ga] decreases. Fraction of photoquenchable defects correlates to defects within 3 nearest neighbor separations disrupting the metastability. Annealing reduces neutral As[sub Ga] content around 500C, similar to irradiation damaged and plastically deformed Ga[sub As], as opposed to bulk grown GaAs in which As[sub Ga]-related defects are stable up to 1100C. The lower temperature defect removal is due to V[sub Ga] enhanced diffusion of As[sub Ga] to As precipitates. The supersaturated V[sub GA] and also decreases during annealing. Annealing kinetics for As[sub Ga]-related defects gives 2.0 [plus minus] 0.3 eV and 1.5 [plus minus] 0.3 eV migration enthalpies for the As[sub Ga] and V[sub Ga]. This represents the difference between Ga and As atoms hopping into the vacancy. The non-photoquenchable As[sub Ga]-related defects anneal with an activation energy of 1.1 [plus minus] 0.3eV. Be acceptors can be activated by 800C annealing. Temperature difference between defect annealing and Be activation formation of As[sub Ga]-Be[sub Ga] pairs. Si donors can only be partially activated.

  3. Defect studies in low-temperature-grown GaAs

    Energy Technology Data Exchange (ETDEWEB)

    Bliss, D.E.

    1992-11-01

    High content of excess As is incorporated in GaAs grown by low-temperature molecular-beam-epitaxy (LTMBE). The excess As exists primarily as As antisite defects AsGa and a lesser extent of gallium vacancies V{sub Ga}. The neutral AsGa-related defects were measured by infrared absorption at 1{mu}m. Gallium vacancies, V{sub Ga}, was investigated by slow positron annihilation. Dependence of defect contents on doping was studied by Si and Be dopants. No free carriers are generated by n-type or p-type doping up to 10{sup 19} cm{sup {minus}3} Si or Be. Raman data indicate Be occupies Ga substitutional sites but Si atom is not substitutional. Si induces more As{sub Ga} in the layer. As As{sub Ga} increases, photoquenchable As{sub Ga} decreases. Fraction of photoquenchable defects correlates to defects within 3 nearest neighbor separations disrupting the metastability. Annealing reduces neutral As{sub Ga} content around 500C, similar to irradiation damaged and plastically deformed Ga{sub As}, as opposed to bulk grown GaAs in which As{sub Ga}-related defects are stable up to 1100C. The lower temperature defect removal is due to V{sub Ga} enhanced diffusion of As{sub Ga} to As precipitates. The supersaturated V{sub GA} and also decreases during annealing. Annealing kinetics for As{sub Ga}-related defects gives 2.0 {plus_minus} 0.3 eV and 1.5 {plus_minus} 0.3 eV migration enthalpies for the As{sub Ga} and V{sub Ga}. This represents the difference between Ga and As atoms hopping into the vacancy. The non-photoquenchable As{sub Ga}-related defects anneal with an activation energy of 1.1 {plus_minus} 0.3eV. Be acceptors can be activated by 800C annealing. Temperature difference between defect annealing and Be activation formation of As{sub Ga}-Be{sub Ga} pairs. Si donors can only be partially activated.

  4. Low seroprevalent species D adenovirus vectors as influenza vaccines.

    Science.gov (United States)

    Weaver, Eric A; Barry, Michael A

    2013-01-01

    Seasonal and pandemic influenza remains a constant threat. While standard influenza vaccines have great utility, the need for improved vaccine technologies have been brought to light by the 2009 swine flu pandemic, highly pathogenic avian influenza infections, and the most recent early and widespread influenza activity. Species C adenoviruses based on serotype 5 (AD5) are potent vehicles for gene-based vaccination. While potent, most humans are already immune to this virus. In this study, low seroprevalent species D adenoviruses Ad26, 28, and 48 were cloned and modified to express the influenza virus A/PR/8/34 hemagglutinin gene for vaccine studies. When studied in vivo, these species D Ad vectors performed quite differently as compared to species C Ad vectors depending on the route of immunization. By intramuscular injection, species D vaccines were markedly weaker than species C vaccines. In contrast, the species D vaccines were equally efficient as species C when delivered mucosally by the intranasal route. Intranasal adenovirus vaccine doses as low as 10(8) virus particles per mouse induced complete protection against a stringent lethal challenge dose of influenza. These data support translation of species D adenoviruses as mucosal vaccines and highlight the fundamental effects of differences in virus tropism on vaccine applications. PMID:23991187

  5. Low-energy particle treatment of GaAs surface

    International Nuclear Information System (INIS)

    The paper presents results of a complex study of surface properties of high-doped (2x1018 cm-3) and semi-insulating GaAs after an interaction with the particles coming from low-energy ion sources such as RF plasma and ion beams. The virgin samples were mechano-chemically polished liquid-encapsulated Czochralski-grown GaAs (100) oriented wafers. The crystals were mounted on the grounded electrode (holder). The mixture Ar+H2 as well as O2 and CF4 were used as working gases: In addition, a combination of two different in-situ exposures was applied, such as e.g. hydrogen and oxygen. Structural, electrical and optical properties of the exposed surfaces were investigated using X-ray diffraction at grazing incidence, quasi-static and high-frequency C-V curve measurements, deep-level transient spectroscopy, photo-reflectance, and photoluminescence. Plasma and ion beam exposures were performed in a commercial RF capacitively coupled plasma equipment SECON XPL-200P and a commercial LPAI device, respectively. The evolution of surface properties as a function of the pressure of working gas and the duration of exposure was observed. (Authors)

  6. Plants as warning signal for exposure to low dose radiation

    International Nuclear Information System (INIS)

    The stamen-hair system of Tradescantia for flower colour has proven to be one of the most suitable materials to study the frequency of mutations induced by low doses of various ionizing radiations and chemical mutagens. The system has also been used successfully for detecting mutagenic synergisms among chemical mutagens and ionizing radiations as well as for studying the variations of spontaneous mutation frequency. In this study of radiobiology, the main objective is to observe somatic mutation (occurrence of pink cells from blue cells) induced on stamen hairs of five Tradescantia sp. available in Malaysia after exposure to low doses of chronic gamma irradiation using Gamma Green House. Pink cells appeared only on Tradescantia Pallida Purpurea stamen hairs after 13 days of exposure to irradiation with different doses of gamma rays. The highest number of stamens with pink cells was recorded from flowers irradiated with the highest dose of 6.37 Gy with 0.07 Gy/ h of dose rate. The lowest number of stamens with pink cells was recorded with an average of 0.57, irradiated with the lowest dose of 0.91 Gy with 0.01 Gy/ h of dose rate. There were no pink cells observed on Tradescantia Spathaceae Discolor after exposure to different doses of gamma rays. Similar negative results were observed for the control experiments. The principal cells in this assay are the mitotic stamen hair cells developing in the young flower buds. After exposure to radiation, the heterozygous dominant blue character of the stamen hair cell is prevented, resulting in the appearance of the recessive pink color. Furthermore, no pink cell appears on all species of Tradescantia spathaceae after irradiated with different doses of gamma rays. The sensitivity of the Tradescantia has been used widely and has demonstrated the relation between radiation dose and frequency of mutation observed at low doses which can contribute to the effects of low doses and their consequences for human health. This system

  7. The Interview as Collaborative Achievement: Interaction, Identity, and Ideology in a Speech Event

    Science.gov (United States)

    Talmy, Steven

    2011-01-01

    This article contrasts a common conceptualization of the interview in applied linguistics, referred to as an "interview as research instrument" perspective, with an alternative, referred to as a "research interview as social practice" orientation. It illustrates implications of the two perspectives on interviews by contrasting a thematic analysis…

  8. High-Power and Low-Threshold-Current-Density GaAs/AlGaAs Quantum Cascade Lasers

    Institute of Scientific and Technical Information of China (English)

    LIU Jun-Qi; LIU Feng-Qi; LI Lu; SHAO Ye; GUO Yu; WANG Zhan-Guo

    2006-01-01

    @@ We report on the realization of GaAs/AlGaAs quantum cascade lasers with an emission wavelength of 9.1 μm above the liquid nitrogen temperature. With optimal current injection window and ridge width of 24 and 60μm respectively, a peak output power more than 500mW is achieved in pulsed mode operation. A low threshold current density Jth = 2.6 kA/cm2 gives the devices good lasing characteristics. In a drive frequency of 1 kHz, the laser operates up to 20% duty cycle.

  9. Using the Achieving Success Everyday (ASE) Group Model to Promote Self-Esteem and Academic Achievement for English as a Second Language (ESL) Students

    Science.gov (United States)

    Shi, Qi; Steen, Sam

    2012-01-01

    The Achieving Success Everyday (ASE) group model is used to promote self-esteem and academic performance of English as a second language (ESL) students. The findings from the preliminary data indicated that the participants' self-esteem was significantly improved after participation in the group. There was no significant improvement in the total…

  10. Self-Beliefs and Behavioural Development as Related to Academic Achievement in Canadian Aboriginal Children

    Science.gov (United States)

    Baydala, Lola; Rasmussen, Carmen; Birch, June; Sherman, Jody; Wikman, Erik; Charchun, Julianna; Kennedy, Merle; Bisanz, Jeffrey

    2009-01-01

    The authors explored the relationship between measures of self-belief, behavioural development, and academic achievement in Canadian Aboriginal children. Standardized measures of intelligence are unable to consistently predict academic achievement in students from indigenous populations. Exploring alternative factors that may be both predictive…

  11. Maternal Employment and Children's Academic Achievement: Parenting Styles as Mediating Variable.

    Science.gov (United States)

    Beyer, Sylvia

    1995-01-01

    Provides a review and integration of findings on the effects of parenting styles and maternal employment on children's academic achievement. Presents a model in which it is argued that maternal employment status has little, if any, direct effect on children's academic achievement. Suggests maternal employment affects parenting styles, which in…

  12. Examining Achievement Goals and Causal Attributions Together as Predictors of Academic Functioning

    Science.gov (United States)

    Wolters, Christopher A.; Fan, Weihua; Daugherty, Stacy G.

    2013-01-01

    This study was designed to forge stronger theoretical and empirical links between achievement goal theory and attribution theory. High school students ("N" = 224) completed a self-report survey that assessed 3 types of achievement goals, 7 types of attributions, and self-efficacy. Results indicated that students' adoption of…

  13. Academic Achievement as a Moderator of Genetic Influences on Alcohol Use in Adolescence

    Science.gov (United States)

    Benner, Aprile D.; Kretsch, Natalie; Harden, K. Paige; Crosnoe, Robert

    2014-01-01

    Prior research suggests a link between academic performance and alcohol use during adolescence, but the degree to which this association reflects actual protective effects continues to be debated. We investigated the role of genetic factors in the association between academic achievement and adolescent alcohol use and whether achievement might…

  14. Angled microfiber arrays as low-modulus, low Poisson's ratio compliant substrates

    International Nuclear Information System (INIS)

    This paper presents a novel fabrication method for producing high-aspect-ratio, angled polymer microfiber arrays by directional pulling of polyethylene from low-aspect-ratio, microporous polycarbonate templates. These arrays represent a novel substrate for electrostatic sensors and actuators because they are characterized by low stiffness (<24 kPa effective elastic modulus), low Poisson's ratio (effectively zero at low strains), and very low density (<1% of solid polyethylene). Validation of these properties is presented by developing a model based on elastica theory, and by performing experiments using a parallel-plate electrostatic actuator fabricated with a fiber array as the dielectric and return spring. (paper)

  15. Time-dependent Networks as Models to Achieve Fast Exact Time-table Queries

    DEFF Research Database (Denmark)

    Brodal, Gerth Stølting; Jacob, Rico

    We consider efficient algorithms for exact time-table queries, i.e. algorithms that find optimal itineraries. We propose to use time-dependent networks as a model and show advantages of this approach over space-time networks as models.......We consider efficient algorithms for exact time-table queries, i.e. algorithms that find optimal itineraries. We propose to use time-dependent networks as a model and show advantages of this approach over space-time networks as models....

  16. Time-Dependent Networks as Models to Achieve Fast Exact Time-Table Queries

    DEFF Research Database (Denmark)

    Brodal, Gert Stølting; Jacob, Rico

    2003-01-01

    We consider efficient algorithms for exact time-table queries, i.e. algorithms that find optimal itineraries for travelers using a train system. We propose to use time-dependent networks as a model and show advantages of this approach over space-time networks as models.......We consider efficient algorithms for exact time-table queries, i.e. algorithms that find optimal itineraries for travelers using a train system. We propose to use time-dependent networks as a model and show advantages of this approach over space-time networks as models....

  17. Intelligence And Self-concept As Co-relates Of Academic Achievement

    OpenAIRE

    Paramjeet Singh Bhadwal; Darshana Sharma

    2012-01-01

    The main purpose of this study is to explore the correlation between intelligence and academic achievement, self-concept and academic achievement among high school students in Jammu city. Two hundred-fifty five students (ninth graders) participated in this study. 142 of whom were female students and 113 were male students. Pearson's Product Moment Coefficient of Correlation was employed for data analysis. Results indicated that there was significant positive relationship bet...

  18. Affective variables as predictors of biology achievement: A study on 11th grade students

    OpenAIRE

    Alpmen Ayten

    2016-01-01

    The purpose of this study was to examine the contribution of the gender, self-efficacy beliefs, task value, and learning strategies to the 11th grade students’ biology achievement. A total of 1035 students from different high schools in Yenimahalle and Çankaya districts of Ankara participated in the study. The Motivated Strategies for Learning Questionnaire [21], (MSLQ) and Biology Achievement Test (BAT) were used to collect data. Results of the the simultaneous multiple regression analysis i...

  19. Parental participation in a chapter I parent center as a predictor of academic achievement

    OpenAIRE

    Johnson, Barbara Ann Lawrence

    1990-01-01

    This study was designed to examine the relationship of participation in the Chapter I Parent Center to four of the variables often associated with academic achievement namely: (1) the child's home environment; (2) parental attitude towards education; (3) the child's self-concept; and (4) the child's motivation to learn. In addition, the study examines the relationship between participation in the Chapter I Parent Center program and reading achievement. The basic objective of th...

  20. Corporate Governance as a Crucial Factor in Achieving Sustainable Corporate Performance

    OpenAIRE

    Julija Bistrova; Natalja Lace; Manuela Tvaronaviciene

    2014-01-01

    In the developed stock markets the corporate governance aspect is crucial in the stock portfolio selection process for investor seeking to achieve shareholder value sustainability. In the emerging markets the importance of the corporate governance role just starts to be realized by the investors and by the corporate managers. The present research, looking at the stock performance leaders and laggards, analyzes whether the corporate governance system matters to achieve long-term shareholder va...

  1. The Achievement Flow Motive as an Element of the Autotelic Personality: Predicting Educational Attainment in Three Cultures

    Science.gov (United States)

    Busch, Holger; Hofer, Jan; Chasiotis, Athanasios; Campos, Domingo

    2013-01-01

    Human behavior is directed by an implicit and an explicit motivational system. The intrinsic form of the implicit achievement motive has been demonstrated to predict the experience of flow. Thus, this achievement flow motive can be considered an integral component of the autotelic personality, posited in Flow Theory as dispositional difference in…

  2. Apparent Retrocausation as a Consequence of Orthodox Quantum Mechanics Refined to Accommodate the Principle of Sufficient Reason

    CERN Document Server

    Stapp, Henry P

    2011-01-01

    The principle of sufficient reason asserts that anything that happens does so for a reason: no definite state of affairs can come into being unless there is a sufficient reason why that particular thing should happen. This principle is usually attributed to Leibniz, although the first recorded Western philosopher to use it was Anaximander of Miletus. The demand that nature be rational, in the sense that it be compatible with the principle of sufficient reason, conflicts with a basic feature of contemporary orthodox physical theory, namely the notion that nature's response to the probing action of an observer is determined by pure chance, and hence on the basis of absolutely no reason at all. This appeal to pure chance can be deemed to have no rational fundamental place in reason-based Western science. It is argued here, on the basis of the other basic principles of quantum physics, that in a world that conforms to the principle of sufficient reason, the usual quantum statistical rules will naturally emerge at...

  3. Retrocausal Effects as a Consequence of Orthodox Quantum Mechanics Refined to Accommodate The Principle of Sufficient Reason

    CERN Document Server

    Stapp, Henry P

    2011-01-01

    The principle of sufficient reason asserts that anything that happens does so for a reason: no definite state of affairs can come into being unless there is a sufficient reason why that particular thing should happen. This principle is usually attributed to Leibniz, although the first recorded Western philosopher to use it was Anaximander of Miletus. The demand that nature be rational, in the sense that it be compatible with the principle of sufficient reason, conflicts with a basic feature of contemporary orthodox physical theory, namely the notion that nature's response to the probing action of an observer is determined by pure chance, and hence on the basis of absolutely no reason at all. This appeal to pure chance can be deemed to have no rational fundamental place in reason-based Western science. It is argued here, on the basis of the other basic principles of quantum physics, that in a world that conforms to the principle of sufficient reason, the usual quantum statistical rules will naturally emerge at...

  4. Retrocausal Effects As A Consequence of Orthodox Quantum Mechanics Refined To Accommodate The Principle Of Sufficient Reason

    Science.gov (United States)

    Stapp, Henry P.

    2011-11-01

    The principle of sufficient reason asserts that anything that happens does so for a reason: no definite state of affairs can come into being unless there is a sufficient reason why that particular thing should happen. This principle is usually attributed to Leibniz, although the first recorded Western philosopher to use it was Anaximander of Miletus. The demand that nature be rational, in the sense that it be compatible with the principle of sufficient reason, conflicts with a basic feature of contemporary orthodox physical theory, namely the notion that nature's response to the probing action of an observer is determined by pure chance, and hence on the basis of absolutely no reason at all. This appeal to pure chance can be deemed to have no rational fundamental place in reason-based Western science. It is argued here, on the basis of the other basic principles of quantum physics, that in a world that conforms to the principle of sufficient reason, the usual quantum statistical rules will naturally emerge at the pragmatic level, in cases where the reason behind nature's choice of response is unknown, but that the usual statistics can become biased in an empirically manifest way when the reason for the choice is empirically identifiable. It is shown here that if the statistical laws of quantum mechanics were to be biased in this way then the basically forward-in-time unfolding of empirical reality described by orthodox quantum mechanics would generate the appearances of backward-time-effects of the kind that have been reported in the scientific literature.

  5. Taste as a didactic approach: enabling students to achieve learning goals

    DEFF Research Database (Denmark)

    Wistoft, Karen; Christensen, Jacob

    2016-01-01

    Teaching does not necessarily condition learning, and specific didactic elements do not necessarily condition the best learning outcome; this also applies to ‘food and meal’ lessons in schools. Teachers’ didactic reflections usually reflect the content and form of the teaching, as well as a numbe...

  6. Beyond Virtual Equality: Liberatory Consciousness as a Path to Achieve Trans* Inclusion in Higher Education

    Science.gov (United States)

    Catalano, D. Chase J.

    2015-01-01

    Trans* men have not, as yet, received specific research attention in higher education. Based on intensive interviews with 25 trans* men enrolled in colleges or universities in New England, I explore their experiences in higher education. I analyze participants' descriptions of supports and challenges in their collegiate environments, as well as…

  7. 3D Lumped LC Resonators as Low Mass Axion Haloscopes

    CERN Document Server

    McAllister, Ben T; Tobar, Michael E

    2016-01-01

    The axion is a hypothetical particle considered to be the most economical solution to the strong CP problem. It can also be formulated as a compelling component of dark matter. The haloscope, a leading axion detection scheme, relies on the conversion of galactic halo axions into real photons inside a resonant cavity structure in the presence of a static magnetic field, where the generated photon frequency corresponds to the mass of the axion. For maximum sensitivity it is key that the central frequency of the cavity mode structure coincides with the frequency of the generated photon. As the mass of the axion is unknown, it is necessary to perform searches over a wide range of frequencies. Currently there are substantial regions of the promising pre-inflationary low mass axion range without any viable proposals for experimental searches. We show that 3D resonant LC circuits with separated magnetic and electric fields, commonly known as re-entrant cavities, can be sensitive dark matter haloscopes in this region...

  8. Low-energy precisions as tests of the fermion substructures

    International Nuclear Information System (INIS)

    The effects are examined of the four-fermion and magnetic coupling terms on the anomalous magnetic and electric dipole moments of leptons, on the Lamb shift in the hydrogen atom, on the Ksub(L)-Ksub(S) mass difference and on the so-called epsilon'/epsilon ratio, where for the weak processes, the recent estimate of the standard model parameters is used. Strong bounds on the values of the compositeness scales associated to each type of light fermion contact term have been derived. The null or negative value of the epsilon'/epsilon CP violating parameter can be achieved by a relatively low value of the compositeness scale (1.2 TeV) of the contact term between light and heavy quarks. Also a relation is derived between the fermion mean squared radius and the compositeness scale. (orig.)

  9. Domestic wastewater treatment as a net energy producer--can this be achieved?

    Science.gov (United States)

    McCarty, Perry L; Bae, Jaeho; Kim, Jeonghwan

    2011-09-01

    In seeking greater sustainability in water resources management, wastewater is now being considered more as a resource than as a waste-a resource for water, for plant nutrients, and for energy. Energy, the primary focus of this article, can be obtained from wastewater's organic as well as from its thermal content. Also, using wastewater's nitrogen and P nutrients for plant fertilization, rather than wasting them, helps offset the high energy cost of producing synthetic fertilizers. Microbial fuel cells offer potential for direct biological conversion of wastewater's organic materials into electricity, although significant improvements are needed for this process to be competitive with anaerobic biological conversion of wastewater organics into biogas, a renewable fuel used in electricity generation. Newer membrane processes coupled with complete anaerobic treatment of wastewater offer the potential for wastewater treatment to become a net generator of energy, rather than the large energy consumer that it is today. PMID:21749111

  10. Three functional aspects of working memory as strong predictors of early school achievements: The review and illustrative evidence

    Directory of Open Access Journals (Sweden)

    Sedek Grzegorz

    2016-04-01

    Full Text Available The paper presents an overview of research on working memory as a predictor of early school achievements. We contrast two main areas of research on the role of working memory in school achievements: the first concerns the structural model of working memory and the second focuses on executive functions. Then, we discuss the facet model of working memory as a promising approach merging the two research branches on working memory tasks as predictors of early school achievements. At the end we present exemplary results of the research conducted on a national sample of six- and seven-year-olds in Poland, which indicates strong relation of working memory functions with the measures of competences in mathematics, reading, and writing. Additionally, the mediation analyses, with parents’ education as a covariate, indicate that the influence of age on achievements in math, reading, and writing in six- and seven-year olds is mediated by working memory functions.

  11. Developing a business strategy to achieve sustainable competitive advantage for Trafin Oil, a.s.

    OpenAIRE

    Noga, Michał

    2011-01-01

    The objective of this thesis is to propose a business strategy that would result in sustainable competitive advantage for Trafin Oil, a.s. - a Czech company operating on the waste oil market. In order to accomplish the stated objective, extensive research has been performed into the existing body of literature on the subject. Frameworks for analysis of the competitive situation are presented and applied thoroughly in the practical part. Moreover, to better comprehend Trafin Oil, a.s. strategi...

  12. Educational Encouragement, Parenting Styles, Gender and Ethnicity as Predictors of Academic Achievement among Special Education Students

    Science.gov (United States)

    Khan, Aqeel; Ahmad, Roslee; Hamdan, Abdul Rahim; Mustaffa, Mohamed Sharif

    2014-01-01

    Current study examines the predictors of academic achievement: role of parenting styles, educational encouragement, gender and ethnicity among special education students. Participants of this study consisted 200 special education students (N = 105 boys and N = 95 girls) age varies 14 to 19 years from one school located at Kuala Lumpur, Malaysia.…

  13. Processing Speed and Intelligence as Predictors of School Achievement: Mediation or Unique Contribution?

    Science.gov (United States)

    Dodonova, Yulia A.; Dodonov, Yury S.

    2012-01-01

    The relationships between processing speed, intelligence, and school achievement were analyzed on a sample of 184 Russian 16-year-old students. Two speeded tasks required the discrimination of simple geometrical shapes and the recognition of the presented meaningless figures. Raven's Advanced Progressive Matrices and the verbal subtests of…

  14. Cognitive Holding Power, Fluid Intelligence, and Mathematical Achievement as Predictors of Children's Realistic Problem Solving

    Science.gov (United States)

    Xin, Ziqiang; Zhang, Li

    2009-01-01

    The present study explored whether first and second order cognitive holding power perceived by children in mathematical classrooms, fluid intelligence, and mathematical achievement predicted their performance on standard problems, and especially realistic problems. A sample of 119 Chinese 4-6th graders were administered the word problem test, the…

  15. Academic Identification as a Mediator of the Relationship between Parental Socialization and Academic Achievement

    Science.gov (United States)

    Strambler, Michael J.; Linke, Lance H.; Ward, Nadia L.

    2013-01-01

    This study examines whether academic identification, or one's psychological and emotional investment in academics, mediates the association between child-reported parental educational socialization and standardized achievement test scores among a predominantly ethnic minority sample of 367 urban middle school students. We predicted that academic…

  16. A History of Black Achievement as Impacted by Federal Court Decisions in the Last Century

    Science.gov (United States)

    Gooden, Mark A.

    2004-01-01

    The major decisions of pre-and post-Brown and the history of African American student achievement are discussed through an analysis of select federal court decisions. One can conclude that the struggle for equal educational opportunity for African Americans in the United States is vying for the attention of more conservative Federal Court judges.

  17. Achievement, Agency, Gender, and Socioeconomic Background as Predictors of Postschool Choices: A Multicontext Study

    Science.gov (United States)

    Parker, Philip D.; Schoon, Ingrid; Tsai, Yi-Miau; Nagy, Gabriel; Trautwein, Ulrich; Eccles, Jacquelynne S.

    2012-01-01

    In this article, the authors develop and test a differential effects model of university entry versus major selection using a set of common predictors, including background factors (gender and socioeconomic status), academic achievement, and academic self-concept. The research used data from 2 large longitudinal databases from Germany (N = 5,048)…

  18. Evoked Prior Learning Experience and Approach to Learning as Predictors of Academic Achievement

    Science.gov (United States)

    Trigwell, Keith; Ashwin, Paul; Millan, Elena S.

    2013-01-01

    Background: In separate studies and research from different perspectives, five factors are found to be among those related to higher quality outcomes of student learning (academic achievement). Those factors are higher self-efficacy, deeper approaches to learning, higher quality teaching, students' perceptions that their workload is…

  19. Learning Environments as Basis for Cognitive Achievements of Students in Basic Science Classrooms in Nigeria

    Science.gov (United States)

    Atomatofa, Rachel; Okoye, Nnamdi; Igwebuike, Thomas

    2016-01-01

    The nature of classroom learning environments created by teachers had been considered very important for learning to take place effectively. This study investigated the effect of creating constructivist and transmissive learning environments on achievements of science students of different ability levels. 243 students formed the entire study…

  20. Does Learning Behavior Augment Cognitive Ability as an Indicator of Academic Achievement?

    Science.gov (United States)

    Yen, Cherng-Jyh; Konold, Timothy R.; McDermott, Paul A.

    2004-01-01

    Measures of cognitive ability have a rich history of accounting for meaningful levels of achievement variance. In contrast to other student characteristics, however, they are somewhat limited in terms of their intervention relevance and treatment validity. Alternatively, children's observable learning behaviors are believed to enhance both…

  1. Mathematical and Reading Difficulties as Predictors of School Achievement and Transition to Secondary Education

    Science.gov (United States)

    Hakkarainen, Airi; Holopainen, Leena; Savolainen, Hannu

    2013-01-01

    This study investigated whether mathematical and reading difficulties and self-reported learning problems predicted school achievement in the ninth grade, at the age of 16, and how these difficulties further explained the transition either to upper secondary academic education or to vocational education. The sample of the present study comprised…

  2. Academic Aptitude and Prior Knowledge as Predictors of Student Achievement in Introduction to Psychology

    Science.gov (United States)

    Thompson, Ross A.; Zamboanga, Byron L.

    2004-01-01

    Earlier research has shown that prior knowledge of psychology is positively associated with course achievement. But are these effects attributable to preexisting differences in general ability or aptitude? The authors administered 2 pretests to 353 students early in an introductory psychology course and obtained measures of general student…

  3. Intrinsic Motivation, Perceived Competence and Classroom Engagement as Longitudinal Predictors of Adolescent Reading Achievement

    Science.gov (United States)

    Froiland, John Mark; Oros, Emily

    2014-01-01

    This study investigated the effects of intrinsic motivation, perceived competence, classroom engagement and extrinsic motivation on reading development among youth. Using a nationally representative sample of students in the US, the researchers followed students longitudinally from fifth to eighth grade. Reading achievement was measured using…

  4. SELF-EFFICACY BELIEFS, ACHIEVEMENT MOTIVATION AND GENDER AS RELATED TO EDUCATIONAL SOFTWARE DEVELOPMENT

    Directory of Open Access Journals (Sweden)

    Alev ATES

    2011-07-01

    Full Text Available This study aims to investigate preservice computer teachers’ self-efficacy beliefs and achievement motivation levels for educational software development before and after the “Educational Software Design, Development and Evaluation (ESDDE” course. A pretest and post test design without a control group was employed. In 2008, 46 senior students (25 male and 21 female who were enrolled at Computer Education and Instructional Technology department participated in this study.The data were collected by the scale of self-efficacy beliefs towards Educational Software Development (ESD, achievement motivation scale besides student demographics form. Positively, the results revealed that the students’ self efficacy beliefs towards educational software development significantly improved after ESDDE course. Before the course, the students’ self-efficacy beliefs were significantly different according to perceived level of programming competency and gender in favor of male, however after the course there was no significant difference in self-efficacy beliefs regarding gender and perceived level of programming competency. Hence, achievement motivation levels after the course were significantly higher than before while gender and perceived level of programming competency had no significant effect on achievement motivation for ESD. The study is considered to contribute studies investigating gender and computer related self efficacy beliefs in IT education.

  5. Online Self-Regulatory Learning Behaviors as a Mediator in the Relationship between Online Course Perceptions with Achievement

    OpenAIRE

    Valerie Paton; Lucy Barnard; William Lan

    2008-01-01

    Positive perceptions of online course communication and collaboration have been associated with better academic outcomes, while self-regulatory learning behaviors have also been linked to academic achievement and other positive learning outcomes. In the current study, we examined whether self-regulatory learning behaviors may be considered as mediating the relationship between student perceptions of online course communication and collaboration with academic achievement as measured by grade p...

  6. Increasing numbers of nonaneurysmal subarachnoid hemorrhage in the last 15 years: antithrombotic medication as reason and prognostic factor?

    Science.gov (United States)

    Konczalla, Juergen; Kashefiolasl, Sepide; Brawanski, Nina; Senft, Christian; Seifert, Volker; Platz, Johannes

    2016-06-01

    OBJECT Subarachnoid hemorrhage (SAH) is usually caused by a ruptured intracranial aneurysm, but in some patients no source of hemorrhage can be detected. More recent data showed increasing numbers of cases of spontaneous nonaneurysmal SAH (NASAH). The aim of this study was to analyze factors, especially the use of antithrombotic medications such as systemic anticoagulation or antiplatelet agents (aCPs), influencing the increasing numbers of cases of NASAH and the clinical outcome. METHODS Between 1999 and 2013, 214 patients who were admitted to the authors' institution suffered from NASAH, 14% of all patients with SAH. Outcome was assessed according to the modified Rankin Scale (mRS) at 6 months. Risk factors were identified based on the outcome. RESULTS The number of patients with NASAH increased significantly in the last 15 years of the study period. There was a statistically significant increase in the rate of nonperimesencephalic (NPM)-SAH occurrence and aCP use, while the proportion of elderly patients remained stable. Favorable outcome (mRS 0-2) was achieved in 85% of cases, but patients treated with aCPs had a significantly higher risk for an unfavorable outcome. Further analysis showed that elderly patients, and especially the subgroup with a Fisher Grade 3 bleeding pattern, had a high risk for an unfavorable outcome, whereas the subgroup of NPM-SAH without a Fisher Grade 3 bleeding pattern had a favorable outcome, similar to perimesencephalic (PM)-SAH. CONCLUSIONS Over the years, a significant increase in the number of patients with NASAH has been observed. Also, the rate of aCP use has increased significantly. Risk factors for an unfavorable outcome were age > 65 years, Fisher Grade 3 bleeding pattern, and aCP use. Both "PM-SAH" and "NPM-SAH without a Fisher Grade 3 bleeding pattern" had excellent outcomes. Patients with NASAH and a Fisher Grade 3 bleeding pattern had a significantly higher risk for an unfavorable outcome and death. Therefore, for further

  7. Accumulation of Experience in a Vast Number of Cases: Enactivism as a Fit Framework for the Study of Spatial Reasoning in Mathematics Education

    Science.gov (United States)

    Khan, Steven; Francis, Krista; Davis, Brent

    2015-01-01

    As we witness a push toward studying spatial reasoning as a principal component of mathematical competency and instruction in the twenty first century, we argue that enactivism, with its strong and explicit foci on the coupling of organism and environment, action as cognition, and sensory motor coordination provides an inclusive, expansive, apt,…

  8. Big Five Personality Traits, Cognitive Appraisals and Emotion Regulation Strategies as Predictors of Achievement Emotions

    Directory of Open Access Journals (Sweden)

    Izabela Sorić

    2013-09-01

    Full Text Available In academic settings, emotions can arise in a variety of contexts and have adverse and interfering effects on learning and performance, especially those of negative valence. Thus, the investigation of their personal antecedents and different strategies implemented by students in order to regulate them, are important topics of research. The aim of this study was to examine the unique contribution of Big Five personality traits (as distal personal antecedents of emotions, cognitive control and value appraisals (as their proximal antecedents and students' tendencies to reappraise or suppress their emotions (as most important emotion regulation strategies for experiencing academic emotions of unhappiness, anger, anxiety and humiliation. The sample consisted of 500 high school students who completed the self-report questionnaire during their regular scheduled classes. The series of multiple hierarchical regression analyses showed that all groups of predictors have made significant and independent contribution to the explanation of all analysed emotions.

  9. English Language Proficiency Tests and Academic Achievement: A Study on the Malaysian University English Test as a Predictor of Technical Programme Undergraduates Academic Achievement

    Directory of Open Access Journals (Sweden)

    Nurhazlini Rahmat

    2015-02-01

    Full Text Available In the Malaysian education system, English has always played an important role. In acknowledging its importance, Malaysian University English Test (MUET has been introduced to enable continued emphasis on this role.  MUET has been made compulsory for those who wish to pursue a first degree programme in local universities. This study aims to examine the relationship between English language proficiency test (as measured by MUET bands to predict the undergraduates academic achievement (as measured by Cumulative Grade Point Average score. It also aims to determine the recommended MUET band as an entry requirement for prospective technical programme undergraduates in Universiti Putra Malaysia (UPM. The study was carried out among 225 final year undergraduates of five different faculties in UPM, namely Faculty of Engineering, Faculty of Forestry, Faculty of Biotechnology and Biomolecular, Faculty of Food Science and Technology, and Faculty of Veterinary Medicine.  The data used were obtained by administering a brief questionnaire and were quantitatively analysed using Statistical Package for Social Science (SPSS version 19.  The study revealed that there is a medium positive correlation between English language proficiency and academic achievement where students who have scored higher bands for MUET are the ones who obtained higher CGPA in their study. Based on the findings, it is recommended that UPM and other local universities make changes towards the minimum MUET entry requirement to help prospective undergraduates excel in their academic study.Keywords: English language proficiency, academic achievement, technical programme, MUET, CGPA

  10. Strategic Planning as a Tool for Achieving Alignment in Academic Health Centers

    OpenAIRE

    Higginbotham, Eve J.; Church, Kathryn C.

    2012-01-01

    After the passage of the Patient Protection and Affordable Care Act in March 2010, there is an urgent need for medical schools, teaching hospitals, and practice plans to work together seamlessly across a common mission. Although there is agreement that there should be greater coordination of initiatives and resources, there is little guidance in the literature to address the method to achieve the necessary transformation. Traditional approaches to strategic planning often engage a few leaders...

  11. Achieving 90–90–90 in paediatric HIV: adolescence as the touchstone for transition success

    OpenAIRE

    Sonia Lee; Rohan Hazra

    2015-01-01

    Introduction: The number of children less than 15 years estimated to be living with HIV globally approximated 3.2 million in 2013. Young people aged 15 to 24 years living with HIV approximated 4 million. The survival of these children and adolescents into adulthood poses new and urgent challenges of transition from the paediatric to adolescent to adult healthcare settings due to emerging developmental, psychosocial and comorbid issues. In order to achieve treatment targets of 90–90–90 across ...

  12. Formal Kindergaten Experience as a Predictor of Academic Achievement of Primary Five Pupils in English Language

    Directory of Open Access Journals (Sweden)

    I.T. Eweniyi

    2012-10-01

    Full Text Available This study investigated the effect of formal kindergarten education on the achievement of primary five pupils. The academic performance of pupils with and without formal kindergarten experience were compared. Their achievement was based on their performance in the English language tests. The sample consisted of one hundred and twenty pupils made up of forty eight pupils with formal kindergarten education and seventy two pupils without formal kindergarten education selected from ten public primary five classes. The sample consisted of boys and girls.The instrument used for data collection was English language achievement tests. The instruments were administered to students in their various schools. The scores obtained from the tests were analysed using the t-test to find the significant difference between the means of the two groups. The results of this study revealed that formal kindergarten education has a long term effect on the performance of primary school pupils since those with formal kindergarten education performed significantly better than those without. Another finding was that the sex of the students has no effect on the academic performance of pupils in primary school.Conclusively, it was confirmed in the study that pupils with formal kindergarten education perform better than those without in Nigerian context at least in primary school, hence this study emphasized the importance of formal kindergarten education.

  13. Differences in Academic Achievement among Texas High School Students as a Function of Music Enrollment

    Science.gov (United States)

    Horton, Robert Wayne

    2012-01-01

    Purpose: The purpose of this study was to examine the score differences on the Texas Academic Knowledge and Skills (TAKS) Reading and Mathematics measures among students in Grades 10 and 11 as a function of music enrollment. Specifically, gender, ethnicity, socioeconomic status, and enrollment in choir, band, or orchestra or no music enrollment…

  14. Educational Goals and Motives as Possible Mediators in the Relationship between Social Support and Academic Achievement

    Science.gov (United States)

    Hernandez, Lucie; Oubrayrie-Roussel, Nathalie; Prêteur, Yves

    2016-01-01

    Perceived social support has been widely recognized as having beneficial effects on a person's development, and adolescence is no exception. The objective of this article is to go beyond this "stereotypical" vision of friendship by showing that social support does not always have a positive and direct effect on adolescents' academic…

  15. Using a Facebook Group as a Forum to Distribute, Answer and Discuss Content: Influence on Achievement

    Science.gov (United States)

    O'Bannon, Blanche W.; Britt, Virginia G.; Beard, Jeffrey L.

    2013-01-01

    This study examined the effectiveness of using a Facebook group to increase preservice teachers' knowledge when one was used as a forum to share, answer, and discuss content-related questions in a technology course required for all students seeking teacher licensure. Further, it examined the students' prior use of Facebook groups, how the…

  16. Entrepreneurship Education in Delta State Tertiary Institution as a Means of Achieving National Growth and Development

    Science.gov (United States)

    Osakwe, Regina N.

    2015-01-01

    This study examined entrepreneurship education in Delta Sate tertiary institutions as a means of national growth and development. Two research questions were asked to guide the study. The population comprised all the 1,898 academic staff in eight tertiary institutions in the state. A sample of 800 lecturers was drawn through the multi stage and…

  17. Exploring the Role of Metonymy in Mathematical Understanding and Reasoning: The Concept of Derivative as an Example

    Science.gov (United States)

    Zandieh, Michelle J.; Knapp, Jessica

    2006-01-01

    In this paper we examine the roles that metonymy may play in student reasoning. To organize this discussion we use the lens of a structured derivative framework. The derivative framework consists of three layers of process-object pairs, one each for ratio, limit, and function. Each of the layers can then be illustrated in any appropriate context,…

  18. Non-participants and reasons for non-participation in a pragmatic trial of energy healing as cancer rehabilitation

    DEFF Research Database (Denmark)

    Techau, Marzcia; Lunde, Anita; Pedersen, Christina Gundgaard;

    2014-01-01

    pragmatic trial of energy healing for rehabilitation for colorectal cancer. Methods: Three to seven days after postal recruitment, all eligible participants (n=783) were contacted by telephone. Reasons given for non-participation were recorded in 5 categories. Data were analyzed using Chi2. Results: More...

  19. Faith, reason and belief in the "Apology for Raymond Sebon": are we Christians as we are Perigordines or Germans?

    Directory of Open Access Journals (Sweden)

    Telma de Souza Birchal

    2006-01-01

    Full Text Available This paper analyzes Montaigne's concept of "faith", in comparison with the concepts of "reason" and "belief", in relation to the role assigned to authority by the author of the Essays. The paper discusses mainly the rather established claim that Montaigne's skepticism would reduce faith to the scope of customs and beliefs.

  20. Nuclear water desalination technology as a tool for achieving Millennium Development Goals (MDGs)

    International Nuclear Information System (INIS)

    Potable water is regarded as one of the essential needs for the attainment of the target of the Millennium Development Goals (MDGs), but every year new countries are affected by growing water problems and Climate change is likely to further stress regions already facing dire water shortages. Recent statistics also shown that 2.3 billion people currently live in water-stressed areas and among them 1.7 billion live in water-scarce areas where the water availability per person is less than 1000 m3/year. Only large-scale commercially available desalination processes will be a solution to the menace of this water shortage. This paper therefore focuses on the results and applications of results of research and development in water desalination using nuclear technology which is evolving as an important option for safe, economic and sustainable supply of large amounts of portable water to meet the ever-increasing worldwide water demand.

  1. Big Five Personality Traits, Cognitive Appraisals and Emotion Regulation Strategies as Predictors of Achievement Emotions

    OpenAIRE

    Izabela Sorić; Zvjezdan Penezić; Irena Burić

    2013-01-01

    In academic settings, emotions can arise in a variety of contexts and have adverse and interfering effects on learning and performance, especially those of negative valence. Thus, the investigation of their personal antecedents and different strategies implemented by students in order to regulate them, are important topics of research. The aim of this study was to examine the unique contribution of Big Five personality traits (as distal personal antecedents of emotions), cognitive control and...

  2. Assessing Distance Vision as Interactional Achievement:A Study of Commensuration in Action

    OpenAIRE

    vom Lehn, Dirk; Webb, Helena; Heath, Christian; Gibson, Will

    2013-01-01

    The paper explores the organization of the Distance Vision Test as a process through which optometrists derive an objective test score from subjective assessments of their clients’ quality of reading out lines of letters. The analysis of video-recorded optometric consultations explores how the standard letter-chart features in the interaction between optometrist and client. It examines specific fragments of test procedures to reveal how aspects of the chart are used by optometrist and client ...

  3. Using Renewable Energy As a tool To Achieve Tourism sustainability in Mediterranean islands

    Directory of Open Access Journals (Sweden)

    Evanthie Michalena

    2009-05-01

    Full Text Available This paper addresses the challenge of transforming Mediterranean islands into sustainable tourism areas, through the direct (or indirect use of renewable energy projects and technologies. Through demonstration and a discussion of cases studies from studied islands, which takes into account island-specific characteristics and particularities, we assess the compatibility of renewable energy technologies (RETs with sustainable tourism development. Conclusions emerge from this analysis which highlight prerequisites for RET-tourism compatibility; this has potential transferability to other insular territories. Developing an appreciation of the factors that can lead to sustainable tourism in islands through the use of renewable energy is a priority issue for two main reasons. Firstly, because until now scientific literature has only discussed the question of photovoltaics’ integration into tourism buildings, and secondly, because of the relatively high vulnerability to climate change impacts of islands compared to many mainland areas, according to predictions made by the United Nations and the European Union. Whilst international politics deal with the mass reduction of gaseous emissions into the atmosphere, reducing the adverse effects of climate change in the islands has become a significant component of national priorities.

  4. Low-E Storm Windows Gain Acceptance as a Home Weatherization Measure

    Energy Technology Data Exchange (ETDEWEB)

    Gilbride, Theresa L.; Cort, Katherine A.

    2016-05-16

    This article for Home Energy Magazine describes work by the U.S. Department of Energy to develop low-emissivity storm windows as an energy efficiency-retrofit option for existing homes. The article describes the low-emissivity invisible silver metal coatings on the glass, which reflect heat back into the home in winter or back outside in summer and the benefits of low-e storm windows including insulation, air sealing, noise blocking, protection of antique windows, etc. The article also describes Pacific Northwest National Laboratory's efforts on behalf of DOE to overcome market barriers to adoption of the technology, including performance validation studies in the PNNL Lab Homes, cost effectiveness analysis, production of reports, brochures, how-to guides on low-e storm window installation for the Building America Solution Center, and a video posted on YouTube. PNNL's efforts were reviewed by the Pacific Northwest Regional Technical Forum (RTF), which serves as the advisory board to the Pacific Northwest Electric Power Planning Council and Bonneville Power Administration. In late July 2015, the RTF approved the low-e storm window measure’s savings and specifications, a critical step in integrating low-e storm windows into energy-efficiency planning and utility weatherization and incentive programs. PNNL estimates that more than 90 million homes in the United States with single-pane or low-performing double-pane windows would benefit from the technology. Low-e storm windows are suitable not only for private residences but also for small commercial buildings, historic properties, and facilities that house residents, such as nursing homes, dormitories, and in-patient facilities. To further assist in the market transformation of low-e storm windows and other high-efficiency window attachments, DOE helped found the window Attachment Energy Rating Council (AERC) in 2015. AERC is an independent, public interest, non-profit organization whose mission is to rate

  5. Achievement Emotions as Predictors of High School Science Success Among African-American and European American Students

    Science.gov (United States)

    Bowe, Marilyn Louise Simmons

    The literature includes few studies of the interrelations of achievement goals and achievement emotions with respect to minority students and science achievement. The objective of this study was to test the control-value theory (CVT) of achievement emotions to determine if the eight discrete achievement emotions would be predictive of test scores on the High School Graduation Test (GHSGT)-Science for African-American compared to European-American science students. Convenience cluster sampling was employed to select 160 students who were all juniors in the same public high school at the time that they took the GHSGT-Science. The central research question for this study aimed to uncover whether any of the eight achievement emotions identified in CVT would contribute significantly to the predictability of science achievement as measured by GHSGT-Science scores. Data were collected using a nonexperimental, cross sectional design survey. Data were analyzed using a hierarchal, forced entry, multiple regression analysis. Key results indicated that the eight achievement emotions were predictive of GHSGT-Science score outcomes. Positive social change at the individual level could reflect a boost in confidence for African American science students and help decrease the achievement gap in science, technology, engineering, and mathematics (STEM) endeavors between European Americans and African-American students. Educators may consider the importance of achievement emotions in science outcomes by including social emotional learning (SEL) as a part of the regular science curriculum. Future researchers should repeat the study in a school district where the population is available to support the desired cluster sample of equal parts European Americans to African Americans and male to female students.

  6. The Effectiveness of Extensive Reading on Students’ Reading Comprehension Achievement as Observed from Students’ Motivation

    Directory of Open Access Journals (Sweden)

    Sarwo Edy

    2015-02-01

    Full Text Available Abstract: The study investagates if the extensive reading activity is effective in improving students’ reading comprehension achievement and if there is any interaction between the extensive reading and the students’ reading motivation.This study employs a quasi-factorial design with a pretest and posttest non-equivalence group design. The subjects of the study were the second semester students of STAIN Curup, Bengkulu in academic year 2011-2012. Students’ reading comprehension achievement was measured by an objective test in the form of multiple choices; students’ reading motivation was profiled and classified by a reading motivation questionnaire. In analyzing the data collected, the re-search used Multivariate Analysis of Covariance. This research reveals the following findings. (1 The students taught by the extensive reading activity showed higher scores than those taught by conventional way. (2 There is no interaction between students’ motivation and extensive reading. Key Words: extensive reading, reading comprehension, effectiveness Abstrak: Studi ini meneliti apakah kegiatan membaca ekstensif efektif meningkatkan prestasi siswa dalam memahami bacaan dan apakah ada interaksi antara membaca ekstensif dan motivasi membaca siswa. Penelitian ini menggunakan quasi-factorial design dengan pre test dan posttest non-equiva-lence group design. Subjek penelitian adalah mahasiswa semester II STAIN Curup, Bengkulu tahun ajaran 2011-2012. Prestasi pemahaman siswa membaca diukur dengan tes objektif dalam bentuk pilih-an ganda; motivasi membaca siswa digambarkan dan diklasifikasikan dengan kuesioner motivasi membaca. Analisis data penelitian menggunakan multivariat analisis kovarians. Hasil penelitian adalah sebagai berikut. (1 Siswa yang dibelajarkan dengan kegiatan membaca ekstensif menunjukkan skor yang lebih tinggi daripada yang dibelajarkan dengan cara konvensional. (2 Tidak ada interaksi antara motivasi belajar siswa dengan membaca

  7. Low Energy Electrons as Probing Tool for Astrochemical Reaction Mechanisms

    Science.gov (United States)

    Hendrik Bredehöft, Jan; Swiderek, Petra; Hamann, Thorben

    hitting anything solid, they will create secondary electrons. These electrons are in fact the energy source needed to run interstellar chemistry. Slow electrons can in principle trigger three different primary processes in a molecule. The first is ionisation by electron impact (EI), which is used to create ions in mass spectrometry. In this process an electron hits a molecule M and knocks an outer shell electron to create a cation. This occurs whenever the electron energy is above the ionisation threshold of the target molecule. Another possibility is the attachment of a slow electron to a molecule to create an anion. This can occur at sharply defined resonance energies specific to the molecule M. A third possibility is to excite the molecule M to a neutral state M∗ .[9] M + e- -> M+ + 2 e- (Electron impact ionisation) M + e- -> M- (Electron attachment) M + e- -> M∗ + e- (Neutral excitation) The created states M+ , M- and M∗ are usually not stable states so they very often dissociate into ions and radicals, which can then further react with neighbouring molecules to form new chemical species. In these chemical reactions some products can be formed even at very low temperatures that would otherwise require a lot of thermal energy and/or special catalysts. The formation of ethylamine from ethylene and ammonia by hydroamination is one such example. The reaction is characterized by a high activation barrier caused by the electronic repulsion between the electron density rich C=C double bound and the lone pair electrons of ammo-nia. The reaction also has a highly negative entropy, so it becomes less favourable at higher temperatures, ruling out heat as a means to facilitate the reaction. In classical chemistry this problem is overcome by the use of catalysts. Unfortunately there still is no general catalyst for this kind of reaction. Recently it was shown that the reaction can efficiently be induced by low energy electron radiation.[10] One of the reaction partners is

  8. The Reasons to Lack of Electronic Banking Achievement in Iran

    Directory of Open Access Journals (Sweden)

    Mohsen Rasoulian

    2011-09-01

    importance of Internet, frameworks andencouraging policies to impress beneficiaries to use electronic banking. The second part introduces the culturalelements as the most important ones and then it attracts our attention to financial elements (the cost of Internetand commissions as the second influencing factor the influence of technical elements is fading away due to theimprovements in banking system. Different parameters like management obstacles also play an important role inthe way of electronic banking. The safety obstacles are influenced by the cultural issues and their direct influenceis not certified. Ghareche and Abdolbaghi introduce Internet foundation and decrease in service expenses,managers and experts, that this study confirms Internet foundation and decrease in service expenses. Moghaliconfirm culture as effective parameter (indirectly. Amade and Jafarpour introduce culture-social, managementand reject financial and technical parameters, that this study only confirms culture-social parameters as effectiveparameter.Conclusion: The result of study does not certify the safety obstacles and cultural, financial, and technicalmanagement obstacles are influencing respectively.

  9. Herbicides as weed control agents: state of the art: II. Recent achievements.

    Science.gov (United States)

    Kraehmer, Hansjoerg; van Almsick, Andreas; Beffa, Roland; Dietrich, Hansjoerg; Eckes, Peter; Hacker, Erwin; Hain, Ruediger; Strek, Harry John; Stuebler, Hermann; Willms, Lothar

    2014-11-01

    In response to changing market dynamics, the discovery of new herbicides has declined significantly over the past few decades and has only seen a modest upsurge in recent years. Nevertheless, the few introductions have proven to be interesting and have brought useful innovation to the market. In addition, herbicide-tolerant or herbicide-resistant crop technologies have allowed the use of existing nonselective herbicides to be extended into crops. An increasing and now major challenge is being posed by the inexorable increase in biotypes of weeds that are resistant to herbicides. This problem is now at a level that threatens future agricultural productivity and needs to be better understood. If herbicides are to remain sustainable, then it is a must that we adopt diversity in crop rotation and herbicide use as well as increase the use of nonchemical measures to control weeds. Nevertheless, despite the difficulties posed by resistant weeds and increased regulatory hurdles, new screening tools promise to provide an upsurge of potential herbicide leads. Our industry urgently needs to supply agriculture with new, effective resistance-breaking herbicides along with strategies to sustain their utility. PMID:25104721

  10. Herbicides as Weed Control Agents: State of the Art: II. Recent Achievements[C

    Science.gov (United States)

    Kraehmer, Hansjoerg; van Almsick, Andreas; Beffa, Roland; Dietrich, Hansjoerg; Eckes, Peter; Hacker, Erwin; Hain, Ruediger; Strek, Harry John; Stuebler, Hermann; Willms, Lothar

    2014-01-01

    In response to changing market dynamics, the discovery of new herbicides has declined significantly over the past few decades and has only seen a modest upsurge in recent years. Nevertheless, the few introductions have proven to be interesting and have brought useful innovation to the market. In addition, herbicide-tolerant or herbicide-resistant crop technologies have allowed the use of existing nonselective herbicides to be extended into crops. An increasing and now major challenge is being posed by the inexorable increase in biotypes of weeds that are resistant to herbicides. This problem is now at a level that threatens future agricultural productivity and needs to be better understood. If herbicides are to remain sustainable, then it is a must that we adopt diversity in crop rotation and herbicide use as well as increase the use of nonchemical measures to control weeds. Nevertheless, despite the difficulties posed by resistant weeds and increased regulatory hurdles, new screening tools promise to provide an upsurge of potential herbicide leads. Our industry urgently needs to supply agriculture with new, effective resistance-breaking herbicides along with strategies to sustain their utility. PMID:25104721

  11. The theory of Realistic Mathematics Education as a theoretical framework for teaching low attainers in mathematics

    Directory of Open Access Journals (Sweden)

    Hayley Barnes

    2005-10-01

    Full Text Available This article recounts the process embarked on and reasons for selecting the theory of Realistic Mathematics Education (RME as the theoretical framework in a study carried out with low attaining learners. In the study an intervention for low attaining grade 8 mathematics learners was implemented in an attempt to improve the understanding of the participants with regard to place value, fractions and decimals, and to identify characteristics of this type of intervention and potential design principles that could be applied in similar interventions. In this article, the theoretical framework for the intervention is discussed and theoretical (rather than empirical reasons for selecting the theory of Realistic Mathematics Education (RME for use with low attainers are put forward. From a literature review that looked at the teaching and learning of mathematics to learners who fall into the category of performing below the required standard, five common aspects emerged. Once these aspects had been identified, a theory in mathematics education was sought that encompassed these five aspects. The theory of RME was subsequently selected as the theoretical framework to drive the design and implementation of the intervention and is being suggested as a possible way forward for working with low attaining learners.

  12. Coping with stress and cognitive interference in student teachers performance as important factors influencing their achievement

    Directory of Open Access Journals (Sweden)

    Cirila Peklaj

    2001-06-01

    Full Text Available The purpose of our study was to investigate the relations between student teachers' strategies for coping with stressful situations, cognitive interference factors and successfulness of presentation of student teachers' seminar work. There were 135 student teachers participating in the study. At the beginning of the semester they filled in the Way of Coping Questionnaire (Folkman & Lazarus, 1988. After their presentation of seminar theme they reported about the cognitive interference factors during the presentation (distractive factors and intrusive thoughts. Different aspects of their performance were also evaluated by the teacher according to the well-known criteria. The analysis of the results showed significant correlations between certain ways of coping, cognitive interference factors and success of performance. Further statistical analysis showed significant differences in experiencing distractive factors and intrusive thoughts during presentation between students with low, medium and high performance success. The importance of successful strategies for coping with verbal presentation and the implications for student teacher education are discussed.

  13. The desmoid tumour: Therapeutic results of surgical intervention as compared to those achieved with radiotherapy

    International Nuclear Information System (INIS)

    Discussion of the case reports of nine patients treated for desmoid tumours in the light of 62 such cases described in the relevant literature between 1975 and 1979. Among the patients analysed for the purposes of this study 9 had desmoid tumours treated at our clinic, while the other 60 cases were described in the relevant literature of the past 5 years. The methods used in this cohort were surgery for 37 patients, radiation for 20 patients, excision and post-surgical radiation for 5 patients and various other treatments for the remaining cases. Careful analysis and assessment of the results led to the conclusion that the vast majority of desmoids can be expected to show a satisfactory response to radiation, even though no clear therapeutic superiority could be established for either radical excision or radiation. If surgery is chosen, this should be carried out with the aim of removing all of the tumour. In circumstances precluding radical excision it appears wise to use post-surgical radiation. Follow-up examinations should be carried out in all patients so as to permit immediate diagnosis and treatment of any recurrent tumours. Each desmoid tumour is to be treated on an individual basis. In small tumours it is safer to remove not only the lesion itself but also some of the surrounding intact tissue, tumours at a more advanced stage should be subjected to radiation or both surgery and subsequent radiotherapy. (orig./MG)

  14. MODELING OF ACMEOGRAMME AS A WAY FOR TEACHERS TO ACHIEVE THE HIGHTS OF PROFESSIONALISM

    Directory of Open Access Journals (Sweden)

    Veronika Viktorovna Lorenz

    2015-10-01

    Full Text Available The topicality of acmeological approach is preconditioned by the innovative processes in modern education, the implementation of the Bologna Declaration, the increased requirements to the competences of the teacher. Today, the quality of education depends on the ability of teachers to make the acmeogramme with the aim to reach the heights of their professionalism. Modeling and implementation of acmeogramme helps to solve the tasks of personal and subjective-operational development of the teacher-professional.Acmeogramme helps the teacher to innovate activities, to improve pedagogical skills and to enhance mobility and activity in research work. Today, the level of competitiveness of a specialist is estimated based on his/her professional competencies that must have interdisciplinary, personal and reflexive character. Competence-based approach implies not only the knowledge but also the skills to apply this knowledge in practice. In this regard, acmeological approach supports and develops the ideas enhancing professional competences of the teacher. The article pays special attention to building up the Acme of the teacher, as it allows to develop a program of selfimprovement and self-development according to the requirements to modern specialists. The article pays attention to the structure of the acme which implies selfanalysis, goal setting, elaboration of program of professional development taking into consideration professional competences, and reflexive component.

  15. The duty to give reasons as a guarantee for a fair trial under the sight of the European Court of Human Rights

    Directory of Open Access Journals (Sweden)

    Marcella Alves Mascarenhas Nardelli

    2015-06-01

    Full Text Available This paper aims to define the outlines of the judicial duty to provide reasons for their decisions in its theoretical aspect - according to contemporary procedural knowledge -, as well as to establish its importance for the concretion of a fair trial. At the same time, the duty to give reasons will be analyzed in a practical perspective according to the case-law of the European Court of Human Rights, with a special emphasis in the case Taxquet v. Belgium and its impact on Jury Trials.

  16. Using Eight Key Questions as an Inquiry-Based Framework for Ethical Reasoning Issues in a General Education Earth Systems and Climate Change Course

    Science.gov (United States)

    Johnson, E. A.; Ball, T. C.

    2014-12-01

    An important objective in general education geoscience courses is to help students evaluate social and ethical issues based upon scientific knowledge. It can be difficult for instructors trained in the physical sciences to design effective ways of including ethical issues in large lecture courses where whole-class discussions are not practical. The Quality Enhancement Plan for James Madison University, "The Madison Collaborative: Ethical Reasoning in Action," (http://www.jmu.edu/mc/index.shtml) has identified eight key questions to be used as a framework for developing ethical reasoning exercises and evaluating student learning. These eight questions are represented by the acronym FOR CLEAR and are represented by the concepts of Fairness, Outcomes, Responsibilities, Character, Liberty, Empathy, Authority, and Rights. In this study, we use the eight key questions as an inquiry-based framework for addressing ethical issues in a 100-student general education Earth systems and climate change course. Ethical reasoning exercises are presented throughout the course and range from questions of personal behavior to issues regarding potential future generations and global natural resources. In the first few exercises, key questions are identified for the students and calibrated responses are provided as examples. By the end of the semester, students are expected to identify key questions themselves and justify their own ethical and scientific reasoning. Evaluation rubrics are customized to this scaffolding approach to the exercises. Student feedback and course data will be presented to encourage discussion of this and other approaches to explicitly incorporating ethical reasoning in general education geoscience courses.

  17. The Problem of Free-Riding in Group Projects: Looking beyond Social Loafing as Reason for Non-Contribution

    Science.gov (United States)

    Hall, David; Buzwell, Simone

    2013-01-01

    The increase in popularity of group work in higher education has been accompanied by an increase in the frequency of reports of students not equally contributing to work within the groups. Referred to as "free-riders", the effect of this behaviour on other students can make group work an unpleasant experience for some. Of most frustration to…

  18. Examining Students' Proportional Reasoning Strategy Levels as Evidence of the Impact of an Integrated LEGO Robotics and Mathematics Learning Experience

    Science.gov (United States)

    Martínez Ortiz, Araceli

    2015-01-01

    The presented study used a problem-solving experience in engineering design with LEGO robotics materials as the real-world mathematics-learning context. The goals of the study were (a) to determine if a short but intensive extracurricular learning experience would lead to significant student learning of a particular academic topic and (b) to…

  19. Self-regulated processes as predictors of students' achievement in music theory in Slovenian elementary music schools

    Directory of Open Access Journals (Sweden)

    Barbara Smolej Fritz

    2010-01-01

    Full Text Available The aim of the present research was to examine the relation between processes of selfregulated learning and achievement in Music Theory (MT, a basic and obligatory subject in Slovenian music schools. A total of 457 fifth- and sixth- grade students (153 boys and 303 girls from 10 different elementary music schools in Slovenia participated in the study. Students completed a questionnaire about affective-motivational processes and a questionnaire about (metacognitive processes of selfregulated learning in MT, as well as achievement test. The final grades were collected at the end of the school year. The results showed that significant correlation exists between almost all affective-motivational and (metacognitive processes of self-regulated learning and achievement. Affective-motivational factors emerged as better predictors of students' achievement than (metacognitive factors. The most important individual predictors were anxiety and competence. It was also found that self-regulated processes explain a greater amount of variance for final grades than for the achievement test.

  20. Dielectric Resonators as Radiation Detectors at Low Temperatures

    Science.gov (United States)

    Yamasaki, N. Y.; Sekiya, N.; Kikuchi, T.; Hoshino, M.; Mitsuda, K.; Sato, K.

    2015-10-01

    GHz LC resonators whose resonance frequency depends on temperature may be put to use as radiation detectors. We have demonstrated that a resonator utilizing STO (SrTiO) at 4 and 2 K detected infrared light emitting diode (LED) light, by a shift of resonance frequency around 2 GHz. A suitable design of a resonator array with temperature-dependent dielectric material will be used as a large-format microcalorimeter array without or with only very small Johnson noise.

  1. Racial/Ethnic Socialization and Parental Involvement in Education as Predictors of Cognitive Ability and Achievement in African American Children

    Science.gov (United States)

    Banerjee, Meeta; Harrell, Zaje A. T.; Johnson, Deborah J.

    2011-01-01

    Racial/ethnic socialization has not been studied in the context of other parenting behaviors such as parental involvement in education and its relationship to children's cognitive outcomes. The present study tested the impact of racial/ethnic socialization and parental involvement in education on cognitive ability and achievement in a sample of…

  2. Middle School Characteristics That Predict Student Achievement, as Measured by the School-Wide California API Score

    Science.gov (United States)

    Paredes, Josie Abaroa

    2013-01-01

    The purpose of this study was to investigate, through quantitative research, effective middle school characteristics that predict student achievement, as measured by the school-wide California API score. Characteristics were determined using an instrument developed by the Office of Superintendent of Public Instruction (OSPI), which asked middle…

  3. The Relationship between the Transformational Leadership Characteristics of Principals, as Perceived by Teachers, and Student Achievement on Standardized Tests

    Science.gov (United States)

    Estapa, Ashley L.

    2009-01-01

    This correlational study examined the relationship between principals' transformational leadership behaviors, as perceived by teachers, and student achievement on standardized tests. Participants in this study included teachers in two suburban high schools and six suburban elementary schools in Georgia. Research demonstrates a correlation between…

  4. Social Integration as a Factor in Academic Achievements of Children: A Case Study of African Immigrants in Louisville, Kentucky

    Science.gov (United States)

    Odetunde, Florence Olayinka

    2013-01-01

    This study explored how social integration of African immigrants in the Louisville metropolitan area of Kentucky could be a factor in the academic achievements of their children. It involved critically investigating how the process of their adjustments as immigrants might have been shaped by various personal and environmental factors such as…

  5. Students' Commitment, Engagement and Locus of Control as Predictor of Academic Achievement at Higher Education Level

    Science.gov (United States)

    Sarwar, Muhammad; Ashrafi, Ghulam Muhammad

    2014-01-01

    The purpose of this study was to analyze Students' Commitment, Engagement and Locus of Control as predictors of Academic Achievement at Higher Education Level. We used analytical model and conclusive research approach to conduct study and survey method for data collection. We selected 369 students using multistage sampling technique from…

  6. Gracilaria lemaneiformis polysaccharide as integrin-targeting surface decorator of selenium nanoparticles to achieve enhanced anticancer efficacy.

    Science.gov (United States)

    Jiang, Wenting; Fu, Yuanting; Yang, Fang; Yang, Yufeng; Liu, Ting; Zheng, Wenjie; Zeng, Lilan; Chen, Tianfeng

    2014-08-27

    The poor permeability of glioma parenchyma represents a major limit for antiglioblastoma drug delivery. Gracilaria lemaneiformis polysaccharide (GLP), which has a high binding affinity to αvβ3 integrin overexpressed in glioma cells, was employed in the present study to functionalize selenium nanoparticles (SeNPs) to achieve antiglioblastoma efficacy. GLP-SeNPs showed satisfactory size distribution, high stability, and selectivity between cancer and normal cells. In U87 glioma cell membrane, which has a high integrin expression level, GLP-SeNPs exhibited significantly higher cellular uptake than unmodified SeNPs. As expected, U87 cells exhibited a greater uptake of GLP-SeNPs than C6 cells with low integrin expression level. Furthermore, the internalization of GLP-SeNPs was inhibited by cyclo-(Arg-Gly-Asp-Phe-Lys) peptides, suggesting that cellular uptake into U87 cells and C6 cells occurred via αvβ3 integrin-mediated endocytosis. For U87 cells, the cytotoxicity of SeNPs decorated by GLP was enhanced significantly because of the induction of various apoptosis signaling pathways. Internalized GLP-SeNPs triggered intracellular reactive oxygen species downregulation. Therefore, p53, MAPKs, and AKT pathways were activated to advance cell apoptosis. These findings suggest that surface decoration of nanomaterials with GLP could be an efficient strategy for design and preparation of glioblastoma targeting nanodrugs. PMID:25073123

  7. Self-Concept and Academic Achievement: Investigating Their Importance as Discriminators of Academic Track Membership in High School.

    Science.gov (United States)

    Byrne, Barbara M.

    1990-01-01

    Using linear discriminant analysis, two samples of Canadian high school students (n=929 and n=968) were tested using measures of self-concept, academic self-concept, and academic achievement. Academic self-concept was more effective than was academic achievement in differentiating between low-track and high-track students. (SLD)

  8. Low molecular weight block copolymers as plasticizers for polystyrene

    DEFF Research Database (Denmark)

    Hansen, Kristoffer Karsten; Nielsen, Charlotte Juel; Hvilsted, Søren

    2005-01-01

    Polystyrene-b-alkyl, polystyrene-b-polybutadiene-b-polystyrene, and polystyrene-b-poly(propylene glycol)monotridecyl ether were synthesized using macro initiators and atom transfer radical polymerization or by esterifications of homopolymers. The aim was a maximum molecular weight of 4 kg/mol and...... minimum polystyrene content of 50 w/w%, which by us is predicted as the limits for solubility of polystyrene-b-alkyl in polystyrene. DSC showed polystyrene was plasticized, as seen by a reduction in glass transition temperature, by block copolymers consisting of a polystyrene block with molecular weight...... of approximately 1 kg/mol and an alkyl block with a molecular weight of approximately of 0.3 kg/mol. The efficiency of the block copolymers as plasticizers increases with decreasing molecular weight and polystyrene content. In addition, polystyrene-b-alkyl is found to be an efficient plasticizer also...

  9. Rice Husk Ash Sandcrete Block as Low Cost Building Material

    Directory of Open Access Journals (Sweden)

    S.P.Sangeetha,

    2016-06-01

    Full Text Available Concrete is a widely used construction material for various types of structures due to its structural stability and strength. The construction industry is today consuming more than 400 million tonnes of concrete every year .Most of the increase in cement demand will be met by the use of supplementary cementing materials, as each ton of Portland cement clinker production is associated with similar amount of CO2 emission, which is a major source of global warming. Partial replacement of ordinary Portland cement with mineral admixtures like fly ash, ground granulated blast furnace slag, silica fume, metakaolin, Rice husk Ash (RHA,etc with plasticizers eliminates these drawbacks. The use of rice husk modifies the physical qualities of fresh cement paste as well as microstructure of paste after hardening. By burning the rice husk under a uncontrolled temperature in the atmosphere, a highly reactive RHA was obtained and the ash was utilized as a supplementary cementing material. This paper presents the effects of using Rice Husk Ash (RHA as a partial cement replacement material in mortar mixes. This work is based on an experimental study of mortar made with replacement of Ordinary Portland Cement (OPC with 10%, 20% 30% & 40% RHA. The properties investigated were the compressive strength, setting time, consistency, workability and specific gravity. Finally, a cost analysis was also done to compare the efficiency of rice husk ash sandcrete blocks. From the test results it can be concluded that rice husk ash can be utilized in day today life of manufacturing building blocks which are more economical and more eco-friendly than the cement concrete blocks which are produced now-a-days.

  10. Identification of ultrafast relaxation processes as a major reason for inefficient exciton diffusion in perylene-based organic semiconductors.

    Science.gov (United States)

    Settels, Volker; Schubert, Alexander; Tafipolski, Maxim; Liu, Wenlan; Stehr, Vera; Topczak, Anna K; Pflaum, Jens; Deibel, Carsten; Fink, Reinhold F; Engel, Volker; Engels, Bernd

    2014-07-01

    The exciton diffusion length (LD) is a key parameter for the efficiency of organic optoelectronic devices. Its limitation to the nm length scale causes the need of complex bulk-heterojunction solar cells incorporating difficulties in long-term stability and reproducibility. A comprehensive model providing an atomistic understanding of processes that limit exciton trasport is therefore highly desirable and will be proposed here for perylene-based materials. Our model is based on simulations with a hybrid approach which combines high-level ab initio computations for the part of the system directly involved in the described processes with a force field to include environmental effects. The adequacy of the model is shown by detailed comparison with available experimental results. The model indicates that the short exciton diffusion lengths of α-perylene tetracarboxylicdianhydride (PTCDA) are due to ultrafast relaxation processes of the optical excitation via intermolecular motions leading to a state from which further exciton diffusion is hampered. As the efficiency of this mechanism depends strongly on molecular arrangement and environment, the model explains the strong dependence of LD on the morphology of the materials, for example, the differences between α-PTCDA and diindenoperylene. Our findings indicate how relaxation processes can be diminished in perylene-based materials. This model can be generalized to other organic compounds. PMID:24909402

  11. Selected Wood Properties of Prunus Africana (Hook Grown in Kenya as Possible Reasons for its High Natural Durability

    Directory of Open Access Journals (Sweden)

    Francis Mburu

    2013-03-01

    Full Text Available Studies were carried out on the influence of Prunus africana heartwood extractives on the growth of selected wood decay fungi. Also, wood chemical and mineral content, dimensional stability and anatomical features of P. africana were studied. Heartwood extractives were tested in 100 ppm and 500 ppm concentrations on white, brown rot, and blue stain fungi and growth inhibition was determined as a factor of time. Dimensional stability was determined by computing the swelling coefficient after the blocks were saturated with moisture. Klason lignin, Kürschner cellulose, extractive and ash contents were determined by standard procedures. Infrared analyses were performed using Perkin Elmer FTIR spectrometer. Microscopic examination was performed using an environmental scanning electron microscope. The results showed that the wood is dimensionally stable, and contains 12.7 % extractives, 37.6 % cellulose and 30.4 % lignin. Extractives deposited in vessels are highly soluble in dichloromethane and mainly composed of terpenes. Extractives were able to inhibit the growth of white rot fungi Coriolus versicolor, brown rot fungi Poria placenta and blue stain fungi Aureobasidium pullulans at different concentrations tested and could explain the high durability of Prunus africana wood species.

  12. Individualization of training process as a leading construction of skiers’ training component in preparation for higher achievements

    Directory of Open Access Journals (Sweden)

    Vorfolomeeva L.A.

    2013-08-01

    Full Text Available The aim was to improve the process of preparation of skiers in preparation for higher achievements. It is spotted urgency of introduction of individualization in the training process, the principles and directions of realization. It is offered individualized relationship seen as consistent instructional techniques and forms of management training athletes. It is proved that increasing individualization rationality of functional reserves of athletes and prevent early retirement. Argues that the correction of the training process is the need for the development of genetic expression in the function of an athlete and popular sports specialization. It is noted that during the preparation of the highest achievements of a fundamentally important point is to ensure that the conditions under which the period of maximum susceptibility athlete to achieve the best results with the same period of the most intense and complex in the coordination for training loads.

  13. Biodiesel as a lubricity additive for ultra low sulfur diesel

    Directory of Open Access Journals (Sweden)

    Subongkoj Topaiboul1 and 2,*

    2010-05-01

    Full Text Available With the worldwide trend to reduce emission from diesel engines, ultra low sulfur diesel has been introduced with thesulfur concentration of less than 10 ppm. Unfortunately, the desulfurization process inevitably reduces the lubricity of dieselfuel significantly. Alternatively, biodiesel, with almost zero sulfur content, has been added to enhance lubricity in an ultralow sulfur diesel. This work has evaluated the effectiveness of the biodiesel amount, sourced from palm and jatropha oil,and origin in ultra low sulfur diesel locally available in the market. Wear scar from a high-frequency reciprocating rig isbenchmarked to the standard value (460 m of diesel fuel lubricity. It was found that very small amount (less than 1% ofbiodiesel from either source significantly improves the lubricity in ultra low sulfur diesel, and the biodiesel from jatropha oilis a superior lubricity enhancer.

  14. Application of a single-board computer as a low-cost pulse generator

    International Nuclear Information System (INIS)

    A BeagleBone Black (BBB) single-board open-source computer was implemented as a low-cost fully programmable pulse generator. The pulse generator makes use of the BBB Programmable Real-Time Unit (PRU) subsystem to achieve a deterministic temporal resolution of 5 ns, an RMS jitter of 290 ps and a timebase stability on the order of 10 ppm. A Python-based software framework has also been developed to simplify the usage of the pulse generator. (paper)

  15. Application of a single-board computer as a low cost pulse generator

    CERN Document Server

    Fedrizzi, Marcus

    2015-01-01

    A BeagleBone Black (BBB) single-board open-source computer was implemented as a low-cost fully programmable pulse generator. The pulse generator makes use of the BBB Programmable Real-Time Unit (PRU) subsystem to achieve a deterministic temporal resolution of 5 ns, an RMS jitter of 290 ps and a timebase stability on the order of 10 ppm. A python based software framework has also been developed to simplify the usage of the pulse generator.

  16. Stable same-sex friendships with higher achieving partners promote mathematical reasoning in lower achieving primary school children.

    Science.gov (United States)

    DeLay, Dawn; Laursen, Brett; Kiuru, Noona; Poikkeus, Anna-Maija; Aunola, Kaisa; Nurmi, Jari-Erik

    2015-11-01

    This study was designed to investigate friend influence over mathematical reasoning in a sample of 374 children in 187 same-sex friend dyads (184 girls in 92 friendships; 190 boys in 95 friendships). Participants completed surveys that measured mathematical reasoning in the 3rd grade (approximately 9 years old) and 1 year later in the 4th grade (approximately 10 years old). Analyses designed for dyadic data (i.e., longitudinal actor-partner interdependence model) indicated that higher achieving friends influenced the mathematical reasoning of lower achieving friends, but not the reverse. Specifically, greater initial levels of mathematical reasoning among higher achieving partners in the 3rd grade predicted greater increases in mathematical reasoning from 3rd grade to 4th grade among lower achieving partners. These effects held after controlling for peer acceptance and rejection, task avoidance, interest in mathematics, maternal support for homework, parental education, length of the friendship, and friendship group norms on mathematical reasoning. PMID:26402901

  17. LINERs as Low-Luminosity Active Galactic Nuclei

    CERN Document Server

    Ho, L C

    1998-01-01

    Many nearby galaxies contain optical signatures of nuclear activity in the form of LINER nuclei. LINERs may be the weakest and most common manifestation of the quasar phenomenon. The physical origin of this class of objects, however, has been ambiguous. I draw upon a number of recent observations to argue that a significant fraction of LINERs are low-luminosity active galactic nuclei.

  18. QR-STEM: Energy and Environment as a Context for Improving QR and STEM Understandings of 6-12 Grade Teachers II. The Quantitative Reasoning

    Science.gov (United States)

    Mayes, R.; Lyford, M. E.; Myers, J. D.

    2009-12-01

    The Quantitative Reasoning in STEM (QR STEM) project is a state level Mathematics and Science Partnership Project (MSP) with a focus on the mathematics and statistics that underlies the understanding of complex global scientific issues. This session is a companion session to the QR STEM: The Science presentation. The focus of this session is the quantitative reasoning aspects of the project. As students move from understandings that range from local to global in perspective on issues of energy and environment, there is a significant increase in the need for mathematical and statistical conceptual understanding. These understandings must be accessible to the students within the scientific context, requiring the special understandings that are endemic within quantitative reasoning. The QR STEM project brings together interdisciplinary teams of higher education faculty and middle/high school teachers to explore complex problems in energy and environment. The disciplines include life sciences, physics, chemistry, earth science, statistics, and mathematics. These interdisciplinary teams develop open ended performance tasks to implement in the classroom, based on scientific concepts that underpin energy and environment. Quantitative reasoning is broken down into three components: Quantitative Literacy, Quantitative Interpretation, and Quantitative Modeling. Quantitative Literacy is composed of arithmetic concepts such as proportional reasoning, numeracy, and descriptive statistics. Quantitative Interpretation includes algebraic and geometric concepts that underlie the ability to interpret a model of natural phenomena which is provided for the student. This model may be a table, graph, or equation from which the student is to make predictions or identify trends, or from which they would use statistics to explore correlations or patterns in data. Quantitative modeling is the ability to develop the model from data, including the ability to test hypothesis using statistical

  19. Trait mindfulness, reasons for living and general symptom severity as predictors of suicide probability in males with substance abuse or dependence.

    Directory of Open Access Journals (Sweden)

    Parvaneh Mohammadkhani

    2015-03-01

    Full Text Available The aim of this study was to evaluate suicide probability in Iranian males with substance abuse or dependence disorder and to investigate the predictors of suicide probability based on trait mindfulness, reasons for living and severity of general psychiatric symptoms.Participants were 324 individuals with substance abuse or dependence in an outpatient setting and prison. Reasons for living questionnaire, Mindfulness Attention Awareness Scale and Suicide probability Scale were used as instruments. Sample was selected based on convenience sampling method. Data were analyzed using SPSS and AMOS.The life-time prevalence of suicide attempt in the outpatient setting was35% and it was 42% in the prison setting. Suicide probability in the prison setting was significantly higher than in the outpatient setting (p<0.001. The severity of general symptom strongly correlated with suicide probability. Trait mindfulness, not reasons for living beliefs, had a mediating effect in the relationship between the severity of general symptoms and suicide probability. Fear of social disapproval, survival and coping beliefs and child-related concerns significantly predicted suicide probability (p<0.001.It could be suggested that trait mindfulness was more effective in preventing suicide probability than beliefs about reasons for living in individuals with substance abuse or dependence disorders. The severity of general symptom should be regarded as an important risk factor of suicide probability.

  20. Strain-Engineered Low-Density InAs Bilayer Quantum Dots for Single Photon Emission

    Institute of Scientific and Technical Information of China (English)

    LI Zhan-Guo; LIU Guo-Jun; LI Lin; FENG Ming; LI Mei; LU Peng; ZOU Yong-Gang; LI Lian-He; GAO Xin

    2010-01-01

    @@ We investigate the growth of strain-engineered low-density InAs bilayer quantum dots(BQDs)on GaAs bymolecular beam epitaxy.Owing to increasing dot size and In composition of the upper QDs,low-density BQDs in a GaAs matrix with an emission wavelength up to 1.4 μm at room temperature are achieved.Such a wavelength is larger than that of conventional QDs in a GaAs matrix(generally of about 1.3 μm).The optical properties of the BQDs are sensitive to annealing temperature used after spacer layer growth.Significant decrease of integrated PL intensity is observed as the annealing temperature increases.At IO K,single photon emission from the BQDs with wavelength around 1.3μm is observed.

  1. Strain-Engineered Low-Density InAs Bilayer Quantum Dots for Single Photon Emission

    International Nuclear Information System (INIS)

    We investigate the growth of strain-engineered low-density InAs bilayer quantum dots (BQDs) on GaAs by molecular beam epitaxy. Owing to increasing dot size and In composition of the upper QDs, low-density BQDs in a GaAs matrix with an emission wavelength up to 1.4 μm at room temperature are achieved. Such a wavelength is larger than that of conventional QDs in a GaAs matrix (generally of about 1.3 μm). The optical properties of the BQDs are sensitive to annealing temperature used after spacer layer growth. Significant decrease of integrated PL intensity is observed as the annealing temperature increases. At 10K, single photon emission from the BQDs with wavelength around 1.3 μm is observed. (condensed matter: structure, mechanical and thermal properties)

  2. Pathways of disadvantage? Walking as a mode of transport among low-income mothers.

    Science.gov (United States)

    Bostock, L

    2001-01-01

    Research shows that lack of car ownership is associated with poorer health. It is often assumed that the reason for this observed relationship is that access to a car--or not--reflects access to household assets. Consequently, lack of car ownership is used as a standard marker of low socio-economic status. However, little attention has been paid to the experience of carlessness in the context of disadvantaged lives. This paper argues that "no access to a car" is not only an indicator of low socio-economic status but of walking as a mode of transport. These arguments are illustrated by data from a study of 30 low-income mothers with young children. Although walking is promoted as both an excellent and inexpensive form of exercise, these data suggest that reliance on walking can have negative effects on the welfare of families. The paper draws on qualitative data to describe the ways in which carlessness restricts access to health and social care resources such as food shops, health-care services and social networks. It also explores the impact of walking on the well being of mothers and their day-to-day relationships with children. This is compounded by walking through areas that are neglected and depressed. The paper concludes that strategies to reduce social exclusion must recognise the contradictory health effects of walking and aim to regenerate the physical fabric of social housing estates as well as improve public transport options. PMID:11560717

  3. Negative ions as a source of low energy neutral beams

    Energy Technology Data Exchange (ETDEWEB)

    Fink, J.H.

    1980-01-01

    Little consideration has been given to the impact of recent developments in negative ion source technology on the design of low energy neutral beam injectors. However, negative ion sources of improved operating efficiency, higher gas efficiency, and smaller beam divergence will lead to neutral deuterium injectors, operating at less than 100 keV, with better operating efficiencies and more compact layouts than can be obtained from positive ion systems.

  4. Uniparental disomy as an explanation of presumptive low penetrance

    Energy Technology Data Exchange (ETDEWEB)

    Sulisalo, T.; Chapelle, A. de la [Univ. of Helsinki (Finland); Kaitila, I. [Univ. of Helsinki (Finland)]|[Helsinki Univ. Central Hospital (Finland)

    1994-09-01

    Reduced penetrance has been proposed to account for an observed deficiency of affected individuals in the recessively inherited developmental disorder, cartilage-hair hypoplasia (CHH, MIM No.250250). We recently mapped the gene for CHH to the short arm of chromosome 9, and have shown that reduced penetrance is an unlikely explanation as no unaffected sibs with a genotype identical to that of the affected children were observed at any of the closest marker loci studied. Here we report that two CHH patients out of 45 Finnish uniplex patients had maternal uniparental disomy (UPD) for chromosome 9. The patients were tested with eighteen chromosome 9-specific markers and no paternal contribution was observed in any of the informative meioses. Paternity was confirmed by typing markers from all autosomes other than chromosome 9, and the X chromosome. Both patients were homozygous for all chromosome 9 markers with the exception of one of them who was heterozygous for the maternal alleles at two marker loci on 9q. Further studies will show what proportion of individuals homozygous for CHH is caused by UPD allowing its quantitative significance to be assessed. Based on the data presented here we propose UPD as a main mechanism contributing to the observed deficiency of affected individuals in CHH families.

  5. Bioreactors as a low cost option for tissue culture

    International Nuclear Information System (INIS)

    Bioreactors are vessels designed for large-scale cell, tissue or organ culture in liquid media. Functionally, plant culture bioreactors can be divided into two broad types: those in which the cultures are immersed partially or temporarily in the medium, and those in which the cultures are continuously submerged. Bioreactors provide more precise control of the plant growth gaseous exchange, illumination, medium agitation, temperature and pH than the conventional culture vessels. Bioreactor-based propagation of plants can increase rate of multiplication and growth of cultures and reduce space, energy and labour requirements in commercial micropropagation. They can therefore be attractive to developing countries as regards new or expanding plant culture facilities, in combination with a conventional laboratory. However, to be cost- effective, use of bioreactors requires indexed plant cultures, and attention to aseptic procedures during handling of plant material. Hence, the integration of bioreactors into production systems should only be attempted by facilities with skilled and experienced propagators. (author)

  6. Low grade inflammation as measured by levels of YKL-40

    DEFF Research Database (Denmark)

    Rathcke, Camilla Noelle; Raymond, Ilan; Kistorp, Caroline;

    2010-01-01

    BACKGROUND: Low grade inflammation is of pathogenic importance in the development of cardiovascular disease (CVD) and type 2 diabetes. The inflammation marker YKL-40 correlates with insulin resistance and is highly expressed in atherosclerotic plaques. We aimed to investigate whether YKL-40 could...... predict overall and cardiovascular (CV) mortality in a 50+ years population without known CVD. METHODS: A representative population sample of 639 individuals aged 50-89 years was recruited from general practices. Examination at baseline included echocardiography and blood and urine samples for CV risk...

  7. Achievement motivation, locus of control and individuality as predictors of participative management in the South African educational environment

    OpenAIRE

    C. A. le Roux; Schmidt, C.; J. M. Schepers

    1997-01-01

    The shift to participative management is considered to be both inevitable and necessary. No study has thus far been reported in the participation literature in terms of predictor variables for participative management. The aim of this study was to investigate whether certain orientations - and in particular, achievement motivation, locus of control and individual vs collective orientations - could be identified that would serve as predictors of an inclination towards participative management....

  8. HEAT PUMP USING SUBSOIL WATERS AS LOW TEMPERATURE HEAT SOURCE

    Directory of Open Access Journals (Sweden)

    Denysova Alla

    2015-08-01

    Full Text Available One of the basic directions of perfection of heat supply systems is the tendency of transition to the low-temperature heating systems based on application of heat pump installations. We consider heat supply system with heat pump installations using subsoil waters. Numerical simulation of thermal processes in the elements of a single-stage and double-stage heat pump systems has been worked out. Values of depths of wells and their quantity, necessary for effective operation of the offered installations, and values of capacity of electric water pumps for subsoil waters unit are calculated. Capacity of compressor electric drive and coefficient of performance of heat pump for the conditions of the city of Odessa are presented.

  9. LEETECH facility as a flexible source of low energy electrons

    CERN Document Server

    Attie, D; Bezshyyko, O; Burmistrov, L; Chaus, A; Colas, P; Fedorchuk, O; Golinka-Bezshyyko, L; Kadenko, I; Krylov, V; Kubytskyi, V; Lopez, R; Monard, H; Rodin, V; Titov, M; Tomassini, D; Variola, A

    2016-01-01

    A new versatile facility LEETECH for detector R&D, tests and calibration is designed and constructed. It uses electrons produced by the photoinjector PHIL at LAL, Orsay and provides a powerful tool for wide range R&D studies of different detector concepts delivering "mono-chromatic" samples of low energy electrons with adjustable energy and intensity. Among other innovative instrumentation techniques, LEETECH will be used for testing various gaseous tracking detectors and studying new Micromegas/InGrid concept which has very promising characteristics of spatial resolution and can be a good candidate for particle tracking and identification. In this paper the importance and expected characteristics of such facility based on detailed simulation studies are addressed.

  10. The Weight of Evidence Does Not Support the Listing of Styrene asReasonably Anticipated to be a Human Carcinogen” in NTP's Twelfth Report on Carcinogens

    OpenAIRE

    Rhomberg, Lorenz R.; Goodman, Julie E.; Prueitt, Robyn L.

    2013-01-01

    Styrene was listed asreasonably anticipated to be a human carcinogen” in the twelfth edition of the National Toxicology Program's Report on Carcinogens based on what we contend are erroneous findings of limited evidence of carcinogenicity in humans, sufficient evidence of carcinogenicity in experimental animals, and supporting mechanistic data. The epidemiology studies show no consistent increased incidence of, or mortality from, any type of cancer. In animal studies, increased incidence ra...

  11. Silicon crystal as a low work function collector

    Science.gov (United States)

    Chang, K. H.; Shimada, K.

    1975-01-01

    A test vehicle with a low work function collector which can be incorporated in a thermionic converter was constructed from standard vacuum components including an ultrahigh vacuum ion pump. The collector assembly was fabricated by diffusion bonding a (100) oriented silicon single crystal to a molybdenum block. The silicon surface was treated with cesium and oxygen to produce an NEA-type condition and the results were tested by photoemission and work function measurements. An n-type silicon collector was successfully activated to a work function of 1.0 eV, which was verified by photoemission spectral yield measurements. The stability test of an activated surface at elevated temperatures was conducted in the range from room temperature to 619 K, which was slightly lower than the designed collector temperature of 700 K. The work function measurements clearly demonstrated that the behavior of cesium replenishment on the activated Si surface was similar in nature to that of a metallic surface; that is, the loss of cesium by thermal desorption could be compensated by maintaining an adequate vapor pressure of cesium.

  12. The low housing standard in Slovenia: Low purchasing power as an eternal excuse

    Directory of Open Access Journals (Sweden)

    Richard Sendi

    2013-01-01

    Full Text Available This article advances and argues the thesis that Slovenia has a low housing standard and that the majority of people live in dwellings that may be described as overcrowded according to internationally recognised standards. Evidence supporting this thesis is provided with the help of statistical data, a comprehensive literature review and a review of the views of various Slovenian authors that have discussed the subject in the past. In addition to an extensive review of domestic and foreign literature, I also highlight the major historical factors that have significantly influenced the implementation and maintenance of the current housing standard. The final part of the article identifies and discusses a widely held false conviction that I characterise as the major obstruction to the introduction of a higher housing standard in Slovenia. In this section, I suggest alternative theoretical explanations for the continued maintenance of the low housing standard. The final aim of the article is to spur concrete actions that will lead to implementing appropriate measures and eventual improvement of the housing standard.

  13. On the Influence of New Media and Methods to Achieve Reasonable Spread

    Institute of Scientific and Technical Information of China (English)

    胡海燕

    2016-01-01

    The emergence of new media not only accelerates the spread of information and brings convenience to people, but also subtly changes every aspect of people's life.This paper aims to discuss the influences that the new media bring for people and the methods that can achieve reasonable spread. All of us have the responsibility and obligation to achieve reasonable spread and make the new media serve better for the human progress.

  14. Low-cost, low-input RNA-seq protocols perform nearly as well as high-input protocols

    Directory of Open Access Journals (Sweden)

    Peter A. Combs

    2015-03-01

    Full Text Available Recently, a number of protocols extending RNA-sequencing to the single-cell regime have been published. However, we were concerned that the additional steps to deal with such minute quantities of input sample would introduce serious biases that would make analysis of the data using existing approaches invalid. In this study, we performed a critical evaluation of several of these low-volume RNA-seq protocols, and found that they performed slightly less well in per-gene linearity of response, but with at least two orders of magnitude less sample required. We also explored a simple modification to one of these protocols that, for many samples, reduced the cost of library preparation to approximately $20/sample.

  15. Learning from agriculture: understanding low-dose antimicrobials as drivers of resistome expansion

    Directory of Open Access Journals (Sweden)

    EllenK.Silbergeld

    2014-06-01

    Full Text Available Antimicrobial resistance is a growing public health challenge worldwide, with agricultural use of antimicrobials being one major contributor to the emergence and dissemination of antimicrobial resistance. Globally, most antimicrobials are used in industrial food animal production, a major context for microbiomes encountering low-doses or subtherapeutic-levels of antimicrobial agents from all mechanistic classes. This modern practice exerts broad eco-evolutionary effects on the gut microbiome of food animals, which is subsequently transferred to animal waste. This waste contains complex constituents that are challenging to treat, including antimicrobial resistance determinants and low-dose antimicrobials. Unconfined storage or land deposition of a large volume of animal waste causes its wide contact with the environment and drives the expansion of the environmental resistome through mobilome facilitated horizontal genet transfer. The expanded environmental resistome, which encompasses both natural constituents and anthropogenic inputs, can persist under multiple stressors from agriculture and may re-enter humans, thus posing a public health risk to humans. For these reasons, this review focuses on agricultural antimicrobial use as a laboratory for understanding low-dose antimicrobials as drivers of resistome expansion, briefly summarizes current knowledge on this topic, highlights the importance of research specifically on environmental microbial ecosystems considering antimicrobial resistance as environmental pollution, and calls attention to the needs for longitudinal studies at the systems level.

  16. Studying the impact of the class tournament as an assessment method on student achievements in physics courses

    CERN Document Server

    Dziob, Daniel; Sokolowska, Dagmara

    2015-01-01

    Testing knowledge is an integral part of summative assessment at schools. It can be performed in many different ways. In this study we propose assessment of physics knowledge by using a tournament approach. Prior to a statistical analysis of the results obtained over a tournament organized in one of Polish high schools, all its specifics are discussed at length, including the types of questions assigned, as well as additional self- and peer-evaluation questionnaires, constituting an integral part of the tournament. The impact of the tournament upon student improvement is examined by confronting the results of a post-test with pre-tournament students' achievements reflected in scores earned in former, written tests. We also present some of students' feedback on the idea of tournament as a tool of assessment. Both the analysis of the tournament results and the students' opinions point to at least several benefits of our approach.

  17. Low Carbon Development: Challenges for China as a Rapidly Industrializing Developing Country

    Institute of Scientific and Technical Information of China (English)

    HongboChen; HuaiguoHu; JiahuaPan

    2005-01-01

    China is in a stage of rapid industrialization. Over the past two decades, the size of the Chinese economy has more than quadrupled and energy consumption has more than doubled. The drive for more industrialization over the next two decades is leading to similar dynamics on a much larger scale. The net increase in emissions of CO2 between 1990 and 2001 amounted to 823 million tons, accounting for 27percent of the world total. Energy supplies and security are key constraints to industrialization; therefore, mitigation of emissions can in fact contribute to the achievement of development goals. There is a need for China to pursue a path of low carbon development. However, low and zero carbon technologies can hardly meet the demands for the physical expansion of the economy. In order to cope with the challenges for low carbon development, factors such as responsibility, capability, and potentials have to be taken into account in an international climate regime.

  18. In Their Own Words: Reasons Underlying the Achievement Striving of Students in Schools

    Science.gov (United States)

    Lee, Minhye; Bong, Mimi

    2016-01-01

    By analyzing the open-ended reasons for studying generated by 3 different groups of Korean middle school students, we aimed to provide partial answers to current issues in achievement goal research that are difficult to resolve solely with the use of survey ratings. We categorized student responses using the achievement goal frameworks of Midgley…

  19. Students' Achievement in Human Circulatory System Unit: The Effect of Reasoning Ability and Gender.

    Science.gov (United States)

    Sungur, Semra; Tekkaya, Ceren

    2003-01-01

    Investigates the effect of gender and reasoning ability on the human circulatory system concepts achievement and attitude toward biology. Reports a statistically significant mean difference between concrete and formal students with regard to achievement and attitude toward biology. (Contains 24 references.) (Author/YDS)

  20. Angle-dependent XPS study of the mechanisms of 'high-low temperature' activation of GaAs photocathode

    International Nuclear Information System (INIS)

    The surface chemical compositions, atomic concentration percentage and layer thickness after 'high-temperature' single-step activation and 'high-low temperature' two-step activation were obtained using quantitative analysis of angle-dependent X-ray photoelectron spectroscopy (XPS). It was found that compared to single-step activation, the thickness of GaAs-O interface barrier had a remarkable decrease, the degree of As-O bond became much smaller and the Ga-O bond became dominating, and at the same time the thickness of (Cs, O) layer also had a deduction while the ratio of Cs to O had no change after two-step activation. The measured spectral response curves showed that a increase of 29% of sensitivity had been obtained after two-step activation. To explore the inherent mechanisms of influences of the evolution of GaAs(Cs, O) surface layers on photoemission, surface electric barrier models based on the experimental results were built. By calculation of electron escape probability it was found that the decrease of thickness of GaAs-O interface barrier and (Cs, O) layer is the main reasons, which explained why higher sensitivity is achieved after two-step activation than single-step activation

  1. Inverted pendulum as low-frequency pre-isolation for advanced gravitational wave detectors

    International Nuclear Information System (INIS)

    We have developed advanced seismic attenuation systems for Gravitational Wave (GW) detectors. The design consists of an Inverted Pendulum (IP) holding stages of Geometrical Anti-Spring Filters (GASF) and pendula, which isolate the test mass suspension from ground noise. The ultra-low-frequency IP suppresses the horizontal seismic noise, while the GASF suppresses the vertical ground vibrations. The three legs of the IP are supported by cylindrical maraging steel flexural joints. The IP can be tuned to very low frequencies by carefully adjusting its load. As a best result, we have achieved an ultra low, ∼12 mHz pendulum frequency for the system prototype made for Advanced LIGO (Laser Interferometer Gravitational Wave Observatory). The measured quality factor, Q, of this IP, ranging from Q∼2500 (at 0.45 Hz) to Q∼2 (at 12 mHz), is compatible with structural damping, and is proportional to the square of the pendulum frequency. Tunable counterweights allow for precise center-of-percussion tuning to achieve the required attenuation up to the first leg internal resonance (∼60 Hz for advanced LIGO prototype). All measurements are in good agreement with our analytical models. We therefore expect good attenuation in the low-frequency region, from ∼0.1to ∼50 Hz, covering the micro-seismic peak. The extremely soft IP requires minimal control force, which simplifies any needed actuation

  2. Inverted pendulum as low-frequency pre-isolation for advanced gravitational wave detectors

    Energy Technology Data Exchange (ETDEWEB)

    Takamori, A. [University of Tokyo, Bunkyo, Tokyo 113-0033 (Japan); Raffai, P. [Eoetvoes Lorand University, Budapest 1117 (Hungary)], E-mail: praffai@bolyai.elte.hu; Marka, S. [Columbia University in the City of New York, New York, NY 10027 (United States); DeSalvo, R.; Sannibale, V.; Tariq, H. [California Institute of Technology, Pasadena, CA 91125 (United States); Bertolini, A. [Deutsches Elektronen-Synchrotron, Hamburg 22607 (Germany); Cella, G. [Dipartmento di Fisica, Universita di Pisa, Pisa (Italy); Viboud, N. [Institut National des Sciences Apliquee at Lyon, Lyon (France); Numata, K. [University of Tokyo, Bunkyo, Tokyo 113-0033 (Japan); Takahashi, R.; Fukushima, M. [National Astronomical Observatory of Japan, Mitaka, Tokyo 181-8588 (Japan)

    2007-11-21

    We have developed advanced seismic attenuation systems for Gravitational Wave (GW) detectors. The design consists of an Inverted Pendulum (IP) holding stages of Geometrical Anti-Spring Filters (GASF) and pendula, which isolate the test mass suspension from ground noise. The ultra-low-frequency IP suppresses the horizontal seismic noise, while the GASF suppresses the vertical ground vibrations. The three legs of the IP are supported by cylindrical maraging steel flexural joints. The IP can be tuned to very low frequencies by carefully adjusting its load. As a best result, we have achieved an ultra low, {approx}12 mHz pendulum frequency for the system prototype made for Advanced LIGO (Laser Interferometer Gravitational Wave Observatory). The measured quality factor, Q, of this IP, ranging from Q{approx}2500 (at 0.45 Hz) to Q{approx}2 (at 12 mHz), is compatible with structural damping, and is proportional to the square of the pendulum frequency. Tunable counterweights allow for precise center-of-percussion tuning to achieve the required attenuation up to the first leg internal resonance ({approx}60 Hz for advanced LIGO prototype). All measurements are in good agreement with our analytical models. We therefore expect good attenuation in the low-frequency region, from {approx}0.1to {approx}50 Hz, covering the micro-seismic peak. The extremely soft IP requires minimal control force, which simplifies any needed actuation.

  3. Achieving high performance in intermediate temperature direct carbon fuel cells with renewable carbon as a fuel source

    International Nuclear Information System (INIS)

    Highlights: • Bamboo fiber and waste paper were pyrolyzed to generate bamboo carbon and waste paper carbon as anode fuels of IT-DCFC. • Superior cell performance was achieved with the waste paper carbon. • The results suggested the high performance was due to the highest thermal reactivity and the catalytic inherent impurities. • Calcite and kaolinite as inherent impurities favored the thermal decomposition and the electrooxidation of carbon. - Abstract: Three kinds of carbon sources obtained from carbon black, bamboo fiber and waste paper were investigated as anode fuels in an intermediate temperature direct carbon fuel cell. The carbon sources were characterized with X-ray photoelectron spectroscopy, thermal gravimetric analysis, etc. The results indicated that the waste paper carbon was more abundant in calcite and kaolinite, and showed higher thermal reactivity in the intermediate temperature range compared with the other two carbon sources. The cell performance was tested at 650 °C in a hybrid single cell, using Sm0.20Ce0.80O2−x as the electrolyte. As a result, the cell fed with waste paper carbon showed the highest performance among the three carbon sources, with a peak power density of 225 mW cm−2. The results indicated that its inherent impurities, such as calcite and kaolinite, might favor the thermal gasification of renewable carbon sources, which resulted in the enhanced performance of the intermediate temperature direct carbon fuel cell

  4. The Weight of Evidence Does Not Support the Listing of Styrene as "Reasonably Anticipated to be a Human Carcinogen" in NTP's Twelfth Report on Carcinogens.

    Science.gov (United States)

    Rhomberg, Lorenz R; Goodman, Julie E; Prueitt, Robyn L

    2013-01-01

    Styrene was listed as "reasonably anticipated to be a human carcinogen" in the twelfth edition of the National Toxicology Program's Report on Carcinogens based on what we contend are erroneous findings of limited evidence of carcinogenicity in humans, sufficient evidence of carcinogenicity in experimental animals, and supporting mechanistic data. The epidemiology studies show no consistent increased incidence of, or mortality from, any type of cancer. In animal studies, increased incidence rates of mostly benign tumors have been observed only in certain strains of one species (mice) and at one tissue site (lung). The lack of concordance of tumor incidence and tumor type among animals (even within the same species) and humans indicates that there has been no particular cancer consistently observed among all available studies. The only plausible mechanism for styrene-induced carcinogenesis-a non-genotoxic mode of action that is specific to the mouse lung-is not relevant to humans. As a whole, the evidence does not support the characterization of styrene as "reasonably anticipated to be a human carcinogen," and styrene should not be listed in the Report on Carcinogens. PMID:23335843

  5. Achievement Goal Orientations and Self Handicapping as Mediator and Moderator of the Relationship between Intrinsic Achievement Motivation and Negative Automatic Thoughts in Adolescence Students

    Science.gov (United States)

    Kapikiran, Sahin

    2012-01-01

    The main purpose of this study was to examine the mediator and moderator role of self-handicapping and achievement goal orientations variables on the relationship between negative automatic thoughts intrinsic achievement motivation in high school students. 586 high school students, ranging in age from 14 to 20 (M = 16.08), adolescence students…

  6. Targeting PCSK9 as a promising new mechanism for lowering low-density lipoprotein cholesterol.

    Science.gov (United States)

    Della Badia, Laura A; Elshourbagy, Nabil A; Mousa, Shaker A

    2016-08-01

    Statins and other lipid-lowering drugs have dominated the market for many years for achievement of recommended levels of low-density lipoprotein cholesterol (LDL-C). However, a substantial number of high-risk patients are unable to achieve the LDL-C goal. Proprotein convertase subtilisin/kexin 9 (PCSK9) has recently emerged as a new, promising key therapeutic target for hypercholesterolemia. PCSK9 is a protease involved in chaperoning the low-density lipoprotein receptor to the process of degradation. PCSK9 inhibitors and statins effectively lower LDL-C. The PCSK9 inhibitors decrease the degradation of the LDL receptors, whereas statins mainly interfere with the synthetic machinery of cholesterol by inhibiting the key rate limiting enzyme, the HMG CoA reductase. PCSK9 inhibitors are currently being developed as monoclonal antibodies for their primary use in lowering LDL-C. They may be especially useful for patients with homozygous familial hypercholesterolemia, who at present receive minimal benefit from traditional statin therapy. The monoclonal antibody PCSK9 inhibitors, recently granted FDA approval, show the most promising safety and efficacy profile compared to other, newer LDL-C lowering therapies. This review will primarily focus on the safety and efficacy of monoclonal antibody PCSK9 inhibitors in comparison to statins. The review will also address new, alternative PCSK9 targeting drug classes such as small molecules, gene silencing agents, apolipoprotein B antisense oligonucleotides, and microsomal triglyceride transfer protein inhibitors. PMID:27133571

  7. Executive functioning and reading achievement in school: a study of Brazilian children assessed by their teachers as "poor readers".

    Science.gov (United States)

    Engel de Abreu, Pascale M J; Abreu, Neander; Nikaedo, Carolina C; Puglisi, Marina L; Tourinho, Carlos J; Miranda, Mônica C; Befi-Lopes, Debora M; Bueno, Orlando F A; Martin, Romain

    2014-01-01

    This study examined executive functioning and reading achievement in 106 6- to 8-year-old Brazilian children from a range of social backgrounds of whom approximately half lived below the poverty line. A particular focus was to explore the executive function profile of children whose classroom reading performance was judged below standard by their teachers and who were matched to controls on chronological age, sex, school type (private or public), domicile (Salvador/BA or São Paulo/SP) and socioeconomic status. Children completed a battery of 12 executive function tasks that were conceptual tapping cognitive flexibility, working memory, inhibition and selective attention. Each executive function domain was assessed by several tasks. Principal component analysis extracted four factors that were labeled "Working Memory/Cognitive Flexibility," "Interference Suppression," "Selective Attention," and "Response Inhibition." Individual differences in executive functioning components made differential contributions to early reading achievement. The Working Memory/Cognitive Flexibility factor emerged as the best predictor of reading. Group comparisons on computed factor scores showed that struggling readers displayed limitations in Working Memory/Cognitive Flexibility, but not in other executive function components, compared to more skilled readers. These results validate the account that working memory capacity provides a crucial building block for the development of early literacy skills and extends it to a population of early readers of Portuguese from Brazil. The study suggests that deficits in working memory/cognitive flexibility might represent one contributing factor to reading difficulties in early readers. This might have important implications for how educators might intervene with children at risk of academic under achievement. PMID:24959155

  8. Low-level radioactive-waste compacts. Status report as of July 1982

    Energy Technology Data Exchange (ETDEWEB)

    1982-07-01

    The Low-Level Radioactive Waste Policy Act (P.L. 96-573), enacted in December 1980, established as federal policy that states take responsibility for providing disposal capacity for low-level radioactive waste (LLW) generated within their borders, except for defense waste and Federal R and D. At the request of Senator James A. McClure, Chairman of the Senate Committee on Energy and Natural Resources, DOE has documented the progress of states individually and collectively in fulfilling their responsibilities under the Public Law. Regionalization through formation of low-level waste compacts has been the primary vehicle by which many states are assuming this responsibility. To date seven low-level waste compacts have been drafted and six have been enacted by state legislatures or ratified by a governor. As indicated by national progress to date, DOE considers the task of compacting achievable by the January 1, 1986, exclusionary date set in law, although several states and NRC questioned this.

  9. Low-level radioactive-waste compacts. Status report as of July 1982

    International Nuclear Information System (INIS)

    The Low-Level Radioactive Waste Policy Act (P.L. 96-573), enacted in December 1980, established as federal policy that states take responsibility for providing disposal capacity for low-level radioactive waste (LLW) generated within their borders, except for defense waste and Federal R and D. At the request of Senator James A. McClure, Chairman of the Senate Committee on Energy and Natural Resources, DOE has documented the progress of states individually and collectively in fulfilling their responsibilities under the Public Law. Regionalization through formation of low-level waste compacts has been the primary vehicle by which many states are assuming this responsibility. To date seven low-level waste compacts have been drafted and six have been enacted by state legislatures or ratified by a governor. As indicated by national progress to date, DOE considers the task of compacting achievable by the January 1, 1986, exclusionary date set in law, although several states and NRC questioned this

  10. Rudimentary, low tech incinerators as a means to produce reactive pozzolan out of sugar cane straw

    International Nuclear Information System (INIS)

    The ashes of agricultural wastes from the processing of sugar cane are recognized as having pozzolanic properties. Burning of these wastes under controlled conditions, e.g. temperature and residence time results in significant improvement in reactivity. There are many reports of low-tech incinerators that have been successfully used to produce reactive rice husk ash in Asia. The paper presents the results of the evaluation of a rudimentary incinerator where sugar cane straw is burnt in order to obtain a reactive ash. The incinerator is designed and constructed according to state-of-the-art recommendations for this kind of device. Various burning trials were performed in order to obtain ash for the experiment. X-ray diffraction analysis performed on powdered ash shows significant presence of amorphous (glassy) material. Lime-pozzolana pastes were prepared. The pastes were subjected to X-ray diffraction, thermo-gravimetric analysis, chemical titration, and SEM observation, as a means to examine the pozzolanicity of the ash via the progress with time of calcium hydroxide consumption, and changes in the pore size distribution and strength. Calcium silicate hydrate phases are the main reaction product of the pozzolanic reaction. The long residence time of the ash in the burning chamber seems to be the reason for the fairly low reactivity of the ash; the reactivity of the ash was not significantly improved in comparison with that of the ash burnt in uncontrolled conditions in the open air

  11. Executive Functioning and Reading Achievement in School: A study of Brazilian Children Assessed by Their Teachers as Poor Readers

    Directory of Open Access Journals (Sweden)

    Pascale M. J. Engel de Abreu

    2014-06-01

    Full Text Available This study examined executive functioning and reading achievement in 106 6- to 8-year-old Brazilian children from a range of social backgrounds of whom approximately half lived below the poverty line. A particular focus was to explore the executive function profile of children whose classroom reading performance was judged below standard by their teachers and who were carefully matched to controls on chronological age, sex, school type (Private or Public, domicile (Salvador/BA or São Paulo/SP, and socioeconomic status. Children completed a battery of 12 executive function tasks that were conceptually tapping cognitive flexibility, working memory, inhibition, and selective attention. Each executive function domain was assessed by several tasks. Principal component analysis extracted four factors that were labeled Working Memory/Cognitive Flexibility, Interference Suppression, Selective Attention, and Response Inhibition. Individual differences in executive functioning components made differential contributions to early reading achievement. The Working Memory/Cognitive Flexibility factor emerged as the best predictor of reading. Group comparisons on computed factor scores showed that the struggling readers presented limitations in Working Memory/Cognitive Flexibility, but not in other executive function components, compared to more skilled readers. These results validate the account that working memory capacity provides a crucial building block for the development of early literacy skills and extends it to a population of early readers of Portuguese from Brazil. The study suggests that deficits in working memory/cognitive flexibility might represent one contributing factor to reading difficulties in early readers which might have important implications for interventions for children at risk of school failure.

  12. Housing conditions as a social determinant of low birthweight and preterm low birthweight

    Directory of Open Access Journals (Sweden)

    Mario Vianna Vettore

    2010-12-01

    Full Text Available OBJECTIVE: To assess the relationship between housing conditions and low birthweight and preterm low birthweight among low-income women. METHODS: A case-control study was conducted with post-partum women living in the city of Rio de Janeiro, Southeast Brazil, in 2003-2005. Two groups of cases, low birthweight (n=96 and preterm low birthweight infants (n=68, were compared against normal weight term controls (n=393. Housing conditions were categorized into three levels: adequate, inadequate, and highly inadequate. Covariates included sociodemographic and anthropometric characteristics, risk behaviors, violence, anxiety, satisfaction during pregnancy, obstetric history and prenatal care. RESULTS: Poor housing conditions was independently associated with low birthweight (inadequate - OR 2.3 [1.1;4.6]; highly inadequate - OR 7.6 [2.1;27.6] and preterm low birthweight (inadequate - OR 2.2 [1.1;4.3]; highly inadequate - OR 7.6 [2.4;23.9] and factors associated with outcomes were inadequate prenatal care and previous preterm birth. Low income and low maternal body mass index remained associated with low birthweight. CONCLUSIONS: Poor housing conditions were associated with low birthweight and preterm low birthweight.

  13. The Effect of Origami-Based Instruction on Spatial Visualization, Geometry Achievement, and Geometric Reasoning

    Science.gov (United States)

    Arici, Sevil; Aslan-Tutak, Fatma

    2015-01-01

    This research study examined the effect of origami-based geometry instruction on spatial visualization, geometry achievement, and geometric reasoning of tenth-grade students in Turkey. The sample ("n" = 184) was chosen from a tenth-grade population of a public high school in Turkey. It was a quasi-experimental pretest/posttest design. A…

  14. Stable isotopes and their relationship to temperature and precipitation as recorded in low latitude ice cores

    International Nuclear Information System (INIS)

    The potential of stable isotopic ratios (18O/16O and 2H/1H) in mid to low latitude glaciers as modern tools for paleoclimate reconstruction is reviewed. The isotopic composition of precipitation should be viewed not only as a powerful proxy indicator of climate, but also as an additional parameter for understanding climate-induced changes in the water cycle, on both regional and global scales. To interpret quantitatively the ice core isotopic records, the response of the isotopic composition of precipitation to long-term fluctuations of key climatic parameters (temperature, precipitation amount, relative humidity) over a given area should be known. Furthermore, it is important to establish the transfer functions that relate the climate-induced changes of the isotopic composition of precipitation to the isotope record preserved in the glacier. The factors that govern the values of stable isotopes in snowfall are enigmatic and as yet no satisfactory model has been developed to link them directly with any one meteorological or oceanographic factor. This is particularly problematic in the high altitude glaciers in the tropics, where complications are present due not only to continental effects, but also to altitude effects and convective air mass instability, particularly in the monsoon climates of the tropics. This paper presents long and short-term perspectives of isotopic composition variations in ice cores spanning the last 25,000 years from the mid- to low-latitude glaciers. The isotopic records will also be examined as a function of the altitude of the individual coring sites which ranges from 5325 meters to 7200 meters. On the short, term isotopic records from ice cores from the Andes of South America, the Tibetan Plateau and Kilimanjaro in Africa through the year 2000 will be presented. All the tropical glaciers for which data exist are disappearing, and these sites show isotopic enrichment in the 20th century that suggests that large scale low latitude warming

  15. Anion control as a strategy to achieve high-mobility and high-stability oxide thin-film transistors.

    Science.gov (United States)

    Kim, Hyun-Suk; Jeon, Sang Ho; Park, Joon Seok; Kim, Tae Sang; Son, Kyoung Seok; Seon, Jong-Baek; Seo, Seok-Jun; Kim, Sun-Jae; Lee, Eunha; Chung, Jae Gwan; Lee, Hyungik; Han, Seungwu; Ryu, Myungkwan; Lee, Sang Yoon; Kim, Kinam

    2013-01-01

    Ultra-definition, large-area displays with three-dimensional visual effects represent megatrend in the current/future display industry. On the hardware level, such a "dream" display requires faster pixel switching and higher driving current, which in turn necessitate thin-film transistors (TFTs) with high mobility. Amorphous oxide semiconductors (AOS) such as In-Ga-Zn-O are poised to enable such TFTs, but the trade-off between device performance and stability under illumination critically limits their usability, which is related to the hampered electron-hole recombination caused by the oxygen vacancies. Here we have improved the illumination stability by substituting oxygen with nitrogen in ZnO, which may deactivate oxygen vacancies by raising valence bands above the defect levels. Indeed, the stability under illumination and electrical bias is superior to that of previous AOS-based TFTs. By achieving both mobility and stability, it is highly expected that the present ZnON TFTs will be extensively deployed in next-generation flat-panel displays. PMID:23492854

  16. A multifunctional DNA origami as carrier of metal complexes to achieve enhanced tumoral delivery and nullified systemic toxicity.

    Science.gov (United States)

    Huang, Yanyu; Huang, Wei; Chan, Leung; Zhou, Binwei; Chen, Tianfeng

    2016-10-01

    The use of metal complexes in cancer treatment is hampered by the insufficient accumulation in tumor regions and observable systemic toxicity due to their nonspecificity in vivo. Herein we present a cancer-targeted DNA origami as biocompatible nanocarrier of metal complexes to achieve advanced antitumor effect. The formation of unique tetrahedral nanostructure of DNA cages effectively enhances the interaction between ruthenium polypyridyl complexes (RuPOP) and the cages, thus increasing the drug loading efficacy. Conjugation of biotin to the DNA-based nanosystem (Bio-cage@Ru) enhances its specific cellular uptake, drug retention and cytotoxicity against HepG2 cells. Different from free RuPOP and the cage itself, Bio-cage@Ru translocates to cell nucleus after internalization, where it undergoes self-immolative cleavage in response to DNases, leading to triggered drug release and induction of ROS-mediated cell apoptosis. Moreover, in the nude mice model, the nanosystem specifically accumulates in tumor sites, thus exhibits satisfactory in vivo antitumor efficacy, and alleviates the damage of liver, kidney, lung and heart function of nude mice induced by RuPOP and tumor xenografts. Collectively, this study demonstrates a strategy for construction of biocompatible and cancer-targeted DNA origami with enhanced anticancer efficacy and reduced toxicity for next-generation cancer therapy. PMID:27388944

  17. The Snapping Elbow Syndrome as a Reason for Chronic Elbow Neuralgia in a Tennis Player – MR, US and Sonoelastography Evaluation

    Science.gov (United States)

    Łasecki, Mateusz; Olchowy, Cyprian; Pawluś, Aleksander; Zaleska-Dorobisz, Urszula

    2014-01-01

    Summary Background Ulnar neuropathy is the second most common peripheral nerve neuropathy after median neuropathy, with an incidence of 25 cases per 100 000 men and 19 cases per 100 000 women each year. Skipping (snapping) elbow syndrome is an uncommon cause of pain in the posterior-medial elbow area, sometimes complicated by injury of the ulnar nerve. One of the reason is the dislocation of the abnormal insertion of the medial triceps head over the medial epicondyle during flexion and extension movements. Others are: lack of the Osboune fascia leading to ulnar nerve instability and focal soft tissue tumors (fibromas, lipomas, etc). Recurrent subluxation of the nerve at the elbow results in a tractional and frictional neuritis with classical symptoms of peripheral neuralgia. As far as we know snapping triceps syndrome had never been evaluated in sonoelastography. Case Report A 28yo semi-professional left handed tennis player was complaining about pain in posterior-medial elbow area. Initial US examination suggest golfers elbow syndrome which occurs quite commonly and has a prevalence of 0.3–0.6% in males and 0–3–1.1% in women and may be associated (approx. 50% of cases) with ulnar neuropathy. However subsequently made MRI revealed unusual distal triceps anatomy, moderate ulnar nerve swelling and lack of medial epicondylitis symptoms. Followed (second) US examination and sonoelastography have detected slipping of the both ulnar nerve and the additional band of the medial triceps head. Discussion Snapping elbow syndrome is a poorly known medical condition, sometimes misdiagnosed as the medial epicondylitis. It describes a broad range of pathologies and anatomical abnormalities. One of the most often reasons is the slipping of the ulnar nerve as the result of the Osborne fascia/anconeus epitrochlearis muscle absence. Simultaneously presence of two or more “snapping reasons” is rare but should be always taken under consideration. Conclusions There are no

  18. The Snapping Elbow Syndrome as a Reason for Chronic Elbow Neuralgia in a Tennis Player – MR, US and Sonoelastography Evaluation

    International Nuclear Information System (INIS)

    Ulnar neuropathy is the second most common peripheral nerve neuropathy after median neuropathy, with an incidence of 25 cases per 100 000 men and 19 cases per 100 000 women each year. Skipping (snapping) elbow syndrome is an uncommon cause of pain in the posterior-medial elbow area, sometimes complicated by injury of the ulnar nerve. One of the reason is the dislocation of the abnormal insertion of the medial triceps head over the medial epicondyle during flexion and extension movements. Others are: lack of the Osboune fascia leading to ulnar nerve instability and focal soft tissue tumors (fibromas, lipomas, etc). Recurrent subluxation of the nerve at the elbow results in a tractional and frictional neuritis with classical symptoms of peripheral neuralgia. As far as we know snapping triceps syndrome had never been evaluated in sonoelastography. A 28yo semi-professional left handed tennis player was complaining about pain in posterior-medial elbow area. Initial US examination suggest golfers elbow syndrome which occurs quite commonly and has a prevalence of 0.3–0.6% in males and 0–3–1.1% in women and may be associated (approx. 50% of cases) with ulnar neuropathy. However subsequently made MRI revealed unusual distal triceps anatomy, moderate ulnar nerve swelling and lack of medial epicondylitis symptoms. Followed (second) US examination and sonoelastography have detected slipping of the both ulnar nerve and the additional band of the medial triceps head. Snapping elbow syndrome is a poorly known medical condition, sometimes misdiagnosed as the medial epicondylitis. It describes a broad range of pathologies and anatomical abnormalities. One of the most often reasons is the slipping of the ulnar nerve as the result of the Osborne fascia/anconeus epitrochlearis muscle absence. Simultaneously presence of two or more “snapping reasons” is rare but should be always taken under consideration. There are no sonoelastography studies describing golfers elbow syndrome

  19. Spin depolarization under low electric fields at low temperatures in undoped InGaAs/AlGaAs multiple quantum well

    International Nuclear Information System (INIS)

    The spin polarization under low electric fields (≤300 V/cm) at low temperatures has been studied in undoped InGaAs/AlGaAs multiple quantum well. The spin polarization was created by optical spin orientation using circularly polarized light and the inverse spin-Hall effect was employed to measure the spin polarization current. We observed an obvious spin depolarization especially at lower temperatures (80–120 K). We ascribed the spin depolarization of the photoinduced electrons to the heating effect from the low electric fields (the low field regime 50–300 V/cm). This spin depolarization due to the heating effect is sensitive to temperature and electric field, suggesting a wide range of potential applications and devices.

  20. Validation of the ultrastable low-noise current amplifier as travelling standard for small direct currents

    CERN Document Server

    Drung, Dietmar; Giblin, Stephen P; Djordjevic, Sophie; Piquemal, Francois; Séron, Olivier; Rengnez, Florentin; Götz, Martin; Pesel, Eckart; Scherer, Hansjörg

    2015-01-01

    An interlaboratory comparison of small-current generation and measurement capability is presented with the ultrastable low-noise current amplifier (ULCA) acting as travelling standard. Various measurements at direct currents between 0.16 nA and 13 nA were performed to verify the degree of agreement between the three national metrology institutes involved in the study. Consistency well within one part per million (ppm) was found. Due to harsh environmental conditions during shipment, the ULCA's transfer accuracy had been limited to about +/-0.4 ppm. Supplemental measurements performed at PTB indicate that further improvements in accuracy are possible. Relative uncertainties of 0.1 ppm are achieved by applying on-site calibration of the ULCA with a suitable cryogenic current comparator.

  1. Using a multimode fiber as a high resolution, low loss spectrometer

    CERN Document Server

    Redding, Brandon

    2015-01-01

    We propose and demonstrate that a conventional multimode fiber can function as a high resolution, low loss spectrometer. The proposed spectrometer consists only of the fiber and a camera that images the speckle pattern generated by interference among the fiber modes. While this speckle pattern is detrimental to many applications, it encodes information about the spectral content of the input signal which can be recovered using calibration data. We achieve a spectral resolution of 0.15 nm over 25 nm bandwidth using 1 meter long fiber, and 0.03 nm resolution over 5 nm bandwidth with a 5 meter fiber. The insertion loss is less than 10%, and the signal to noise ratio in the reconstructed spectra is over 1000.

  2. Design and implementation of 83-nm low noise InP-based InAlAs/InGaAs PHEMTs

    Science.gov (United States)

    Zhiming, Wang; Zhuobin, Zhao; Zhifu, Hu; Hui, Huang; Yuxing, Cui; Xiguo, Sun; Jianghui, Mo; Liang, Li; Xingchang, Fu; Xin, Lü

    2015-08-01

    83-nm T-shaped gate InP-based In0.52Al0.48As/In0.65Ga0.35As pseudomorphic high electron mobility transistors (PHEMTs) with excellent DC and RF performance as well as low noise characteristics are reported, including a maximum saturation current density Idss of 894 mA/mm, a maximum extrinsic transconductance gm; max of 1640 mS/mm, an extrapolated cutoff frequency ft of 247 GHz and a maximum oscillation frequency fmax of 392 GHz which were based on the measured S-parameters from 1 to 110 GHz. The minimum noise figure (NFmin) measured by the cold-source method is 1 dB at 30 GHz associated with a gain of 14.5 dB at Vds of 0.8 V and Ids of 17 mA. These results were obtained by the combination of increased InAs mole fraction in the channel, gate size scaling, parasitic reduction and the quantization channel. These excellent results make it one of the most suitable devices for millimeter wave (MMW) low noise applications. Project supported by the National Natural Science Foundation of China (No. 61275107).

  3. The introduction of the personnel dosimetry information system in Greece designed as a relational database and the improvements achieved

    International Nuclear Information System (INIS)

    Dose record keeping is the making and keeping of personnel dose records for radiation workers. It is an essential part of the process of monitoring the exposure of individuals to radiation and shares in the same objectives. The dose record keeping is becoming more and more critical because of the importance of statistical analysis and epidemiological studies in radiation protection, and of the increasing cooperation and exchange of personnel between countries.The GAEC's personnel dosimetry laboratory assures the personnel dosimetry all over the country and keeps the official central dose record.The personnel dosimetry information system had been established in an electronic form on 1989 in Cobol language. Since then appeared various arguments that imposed the change of the data base used. Some of them are: 1. There was no distinction between establishments and their laboratories. 2. The workers did not have a unique code number. consequently, the total dose of a person working in more than one place could not't be estimated. The workers were directly related to their workplace, so if somebody changed his working place he was treated as a new entry, resulting an overestimation of the number of monitored workers introducing an source of errors in the collective and average dose calculations. 3. With the increasing applications of the ionising radiations many types of dosemeters became indispensable e.g. for beta and gamma, for neutrons and for the extremities. Also, the new category of outside workers appeared requesting a special treatment. All these distinctions were not achievable with the previous system. 4. Last years appeared an increasing, interesting in statistical analysis of the personal doses. A program written in Cobol does not't offer many possibilities and has no flexibility for such analysis. The new information system has been rebuilt under the design of a relational database with more possibilities and more flexibility. (authors)

  4. Surfactant-free CZTS nanoparticles as building blocks for low-cost solar cell absorbers

    Science.gov (United States)

    Zaberca, O.; Oftinger, F.; Chane-Ching, J. Y.; Datas, L.; Lafond, A.; Puech, P.; Balocchi, A.; Lagarde, D.; Marie, X.

    2012-05-01

    A process route for the fabrication of solvent-redispersible, surfactant-free Cu2ZnSnS4 (CZTS) nanoparticles has been designed with the objective to have the benefit of a simple sulfide source which advantageously acts as (i) a complexing agent inhibiting crystallite growth, (ii) a surface additive providing redispersion in low ionic strength polar solvents and (iii) a transient ligand easily replaced by an carbon-free surface additive. This multifunctional use of the sulfide source has been achieved through a fine tuning of ((Cu2+)a(Zn2+)b(Sn4+)c(Tu)d(OH-)e)t+, Tu = thiourea) oligomers, leading after temperature polycondensation and S2- exchange to highly concentrated (c > 100 g l-1), stable, ethanolic CZTS dispersions. The good electronic properties and low-defect concentration of the sintered, crack-free CZTSe films resulting from these building blocks was shown by photoluminescence investigation, making these building blocks interesting for low-cost, high-performance CZTSe solar cells.

  5. Surfactant-free CZTS nanoparticles as building blocks for low-cost solar cell absorbers.

    Science.gov (United States)

    Zaberca, O; Oftinger, F; Chane-Ching, J Y; Datas, L; Lafond, A; Puech, P; Balocchi, A; Lagarde, D; Marie, X

    2012-05-11

    A process route for the fabrication of solvent-redispersible, surfactant-free Cu₂ZnSnS₄ (CZTS) nanoparticles has been designed with the objective to have the benefit of a simple sulfide source which advantageously acts as (i) a complexing agent inhibiting crystallite growth, (ii) a surface additive providing redispersion in low ionic strength polar solvents and (iii) a transient ligand easily replaced by an carbon-free surface additive. This multifunctional use of the sulfide source has been achieved through a fine tuning of ((Cu²⁺)(a)(Zn²⁺)(b)(Sn⁴⁺)(c)(Tu)(d)(OH⁻)(e))(t⁺), Tu = thiourea) oligomers, leading after temperature polycondensation and S²⁻ exchange to highly concentrated (c > 100 g l⁻¹), stable, ethanolic CZTS dispersions. The good electronic properties and low-defect concentration of the sintered, crack-free CZTSe films resulting from these building blocks was shown by photoluminescence investigation, making these building blocks interesting for low-cost, high-performance CZTSe solar cells. PMID:22513652

  6. Low-dark current 1024×1280 InGaAs PIN arrays

    Science.gov (United States)

    Yuan, Ping; Chang, James; Boisvert, Joseph C.; Karam, Nasser

    2014-06-01

    Photon counting imaging applications requires low noise from both detector and readout integrated circuit (ROIC) arrays. In order to retain the photon-counting-level sensitivity, a long integration time has to be employed and the dark current has to be minimized. It is well known that the PIN dark current is sensitive to temperature and a dark current density of 0.5 nA/cm2 was demonstrated at 7 °C previously. In order to restrain the size, weight, and power consumption (SWaP) of cameras for persistent large-area surveillance on small platforms, it is critical to develop large format PIN arrays with small pitch and low dark current density at higher operation temperatures. Recently Spectrolab has grown, fabricated and tested 1024x1280 InGaAs PIN arrays with 12.5 μm pitch and achieved 0.7 nA/cm2 dark current density at 15 °C. Based on our previous low-dark-current PIN designs, the improvements were focused on 1) the epitaxial material design and growth control; and 2) PIN device structure to minimize the perimeter leakage current and junction diffusion current. We will present characterization data and analyses that illustrate the contribution of various dark current mechanisms.

  7. Primary Reference Fuels (PRFs) as Surrogates for Low Sensitivity Gasoline Fuels

    KAUST Repository

    Bhavani Shankar, Vijai Shankar

    2016-04-05

    Primary Reference Fuels (PRFs) - binary mixtures of n-heptane and iso-octane based on Research Octane Number (RON) - are popular gasoline surrogates for modeling combustion in spark ignition engines. The use of these two component surrogates to represent real gasoline fuels for simulations of HCCI/PCCI engines needs further consideration, as the mode of combustion is very different in these engines (i.e. the combustion process is mainly controlled by the reactivity of the fuel). This study presents an experimental evaluation of PRF surrogates for four real gasoline fuels termed FACE (Fuels for Advanced Combustion Engines) A, C, I, and J in a motored CFR (Cooperative Fuels Research) engine. This approach enables the surrogate mixtures to be evaluated purely from a chemical kinetic perspective. The gasoline fuels considered in this study have very low sensitivities, S (RON-MON), and also exhibit two-stage ignition behavior. The first stage heat release, which is termed Low Temperature Heat Release (LTHR), controls the combustion phasing in this operating mode. As a result, the performance of the PRF surrogates was evaluated by its ability to mimic the low temperature chemical reactivity of the real gasoline fuels. This was achieved by comparing the LTHR from the engine pressure histories. The PRF surrogates were able to consistently reproduce the amount of LTHR, closely match the phasing of LTHR, and the compression ratio for the start of hot ignition of the real gasoline fuels. This suggests that the octane quality of a surrogate fuel is a good indicator of the fuel’s reactivity across low (LTC), negative temperature coefficient (NTC), and high temperature chemical (HTC) reactivity regimes.

  8. Growth and characterization of InAs quantum dots with low-density and long emission wavelength

    Institute of Scientific and Technical Information of China (English)

    Lin Li; Guojun Liu; Zhanguo Li; Mei Li; Xiaohua Wang

    2008-01-01

    The growth parameters affecting the deposition of self-assembled InAs quantum dots (QDs) on GaAs substrate by low-pressure metal-organic chemical vapor deposition (MOCVD) are reported. The low-density InAs QDs (~ 5 × 108 cm-2) are achieved using high growth temperature and low InAs coverage. Photolu-minescence (PL) measurements show the good optical quality of low-density QDs. At room temperature,the ground state peak wavelength of PL spectrum and full-width at half-maximum (FWHM) are 1361 nm and 23 meV (35 nm), respectively, which are obtained as the GaAs capping layer grown using triethylgallium (TEG) and tertiallybutylarsine (TBA). The PL spectra exhibit three emission peaks at 1361, 1280,and 1204 nm, which correspond to the ground state, the first excited state, and the second excited state of the QDs, respectively.

  9. Low-noise AlGaAs/InGaAs/GaAs pseudomorphic high electron mobility transistor recessed by electron cyclotron resonance plasma etching

    CERN Document Server

    Lee, J H; Lee, C W; Yoon, H S; Park, B S; Park, C S

    1999-01-01

    GaAs pseudomorphic high electron mobility transistor recessed by electron cyclotron resonance (ECR) plasma etching have been investigated. We used a BCl sub 3 /SF sub 6 gas mixture to implement the gate recess process. We obtained a uniformity of the threshold voltage to within 50 mV in 3-inch wafers. The GaAs PHEMTs with a 0.2-mu m gate length recessed by the ECR plasma exhibited a minimum noise figure (NF sub m sub i sub n) as low as 0.26 dB with an associated gain (G sub a) of 13 dB at 12 GHz. At 18 GHz, the NF sub m sub i sub n was 0.47 dB with a Ga of 11.66 dB. These results suggest that the ECR plasma etching process reported here is suitable as a manufacturing process for gate recess of a GaAs PHEMT.

  10. Reasons for choosing dentistry as a career--a survey of dental students attending a dental school in Ireland during 1998-99.

    Science.gov (United States)

    Hallissey, J; Hannigan, A; Ray, N

    2000-05-01

    The motivations for choosing dentistry as a career in the Republic of Ireland are not clearly defined. To better understand why students choose this occupation, 150 undergraduate dental students of all grades at a University Dental School were surveyed during the academic year 1998-99. Candidates were asked to score the influence of certain factors on their decision to choose dentistry as a career, and were given the opportunity to add commentary. The overall response rate was 80.6%. About 2/3 indicated dentistry was their 1st career choice, with medicine being the primary alternative. Reasons for choosing dentistry included perceived ease of employment, being self-employed, working regular hours, followed by an opportunity of good income, and the opportunity to help people. Having relatives or friends in the profession and lifelong ambition were the least important factors for this sample. Extrinsic factors relating to employment conditions had a strong positive correlation (p<0.0001) with each other, while lifelong ambition had a strong negative correlation (p=0.004) with significant financial reward. No significant differences were found in most responses when analysed by gender or year in school. It is concluded that this sample of students is attracted to dentistry primarily due to a positive perception of working conditions, followed by the altruistic motivations of helping people and improving their appearance. PMID:11168467

  11. The Effects of Different Approaches to Reading Instruction on Letter Detection Tasks in Normally Achieving and Low Achieving Readers

    Science.gov (United States)

    Faust, Miriam; Kandelshine-Waldman, Osnat

    2011-01-01

    The present study used two letter detection tasks, the classic missing letter effect paradigm and a single word versus familiar word compound version of this paradigm, to study bottom-up and top-down processes involved in reading in normally achieving as compared to low achieving elementary school readers. The research participants were children…

  12. High performance InAs quantum dot lasers on silicon substrates by low temperature Pd-GaAs wafer bonding

    International Nuclear Information System (INIS)

    InAs quantum dot (QD) laser heterostructures have been grown by molecular beam epitaxy system on GaAs substrates, and then transferred to silicon substrates by a low temperature (250 °C) Pd-mediated wafer bonding process. A low interfacial resistivity of only 0.2 Ω cm2 formed during the bonding process is characterized by the current-voltage measurements. The InAs QD lasers on Si exhibit comparable characteristics to state-of-the-art QD lasers on silicon substrates, where the threshold current density Jth and differential quantum efficiency ηd of 240 A/cm2 and 23.9%, respectively, at room temperature are obtained with laser bars of cavity length and waveguide ridge of 1.5 mm and 5 μm, respectively. The InAs QD lasers also show operation up to 100 °C with a threshold current density Jth and differential quantum efficiency ηd of 950 A/cm2 and 9.3%, respectively. The temperature coefficient T0 of 69 K from 60 to 100 °C is characterized from the temperature dependent Jth measurements

  13. High performance InAs quantum dot lasers on silicon substrates by low temperature Pd-GaAs wafer bonding

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Zihao; Preble, Stefan F. [Microsystems Engineering, Rochester Institute of Technology, Rochester, New York 14623 (United States); Yao, Ruizhe; Lee, Chi-Sen; Guo, Wei, E-mail: wei-guo@uml.edu [Physics and Applied Physics Department, University of Massachusetts Lowell, Lowell, Massachusetts 01854 (United States); Lester, Luke F. [Bradley Department of Electrical and Computer Engineering, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24061 (United States)

    2015-12-28

    InAs quantum dot (QD) laser heterostructures have been grown by molecular beam epitaxy system on GaAs substrates, and then transferred to silicon substrates by a low temperature (250 °C) Pd-mediated wafer bonding process. A low interfacial resistivity of only 0.2 Ω cm{sup 2} formed during the bonding process is characterized by the current-voltage measurements. The InAs QD lasers on Si exhibit comparable characteristics to state-of-the-art QD lasers on silicon substrates, where the threshold current density J{sub th} and differential quantum efficiency η{sub d} of 240 A/cm{sup 2} and 23.9%, respectively, at room temperature are obtained with laser bars of cavity length and waveguide ridge of 1.5 mm and 5 μm, respectively. The InAs QD lasers also show operation up to 100 °C with a threshold current density J{sub th} and differential quantum efficiency η{sub d} of 950 A/cm{sup 2} and 9.3%, respectively. The temperature coefficient T{sub 0} of 69 K from 60 to 100 °C is characterized from the temperature dependent J{sub th} measurements.

  14. Anomalously low thermal conductivity and thermoelectric properties of new cationic clathrates in the Sn-In-As-I system

    International Nuclear Information System (INIS)

    Single-crystal samples of cationic clathrates in the Sn-In-As-I system with different indium contents have been synthesized. Their crystal structure has been analyzed and their thermoelectric properties have been measured. These compounds are found to be n-type semiconductors with high absolute values of the Seebeck coefficient (S = 400–600 μV/K) and anomalously low thermal conductivity (κ ≤ 0.4 W/(m/K) at 300 K, which is characteristic of amorphous materials. The reasons for the anomalously low thermal conductivity of these semiconductors are discussed and ways for optimizing their thermoelectric properties are shown.

  15. The influence of a learning strategies programme on low achieving black secondary school students' academic achievement / Zelbia Sprang

    OpenAIRE

    Sprang, Zelbia

    2001-01-01

    The purpose of this study was to determine, by means of a review of literature and an empirical investigation, the influence of a learning strategies pro!:,rramme on low achieving Black Secondary School students' academic achievement. From the review ofliterature and the empirical study it was concluded that the effective use of learning strategies have an influence on academic achievement defined as Grade Point Average (GPA). It was also concluded that the effective use ofleam...

  16. EXAMINATION MANAGEMENT AS A WAY OF ACHIEVING QUALITY ASSURANCE IN ODL INSTITUTIONS: The Case of Zimbabwe Open University

    Directory of Open Access Journals (Sweden)

    Onias MAFA

    2013-01-01

    Full Text Available An examination is an important component of any institution that educates people. It is a form of assessment used to measure the students’ understanding of the concepts and principles they would have learnt. Zimbabwe Open University, an Open and Distance Learning institution has been setting its own examinations for the academic programmes offered. Through examinations, ZOU students are encouraged to take an active role in analysing and questioning the things they would have learnt. This paper discusses the examinations management at ZOU with a special focus on the setting, administering, marking right up to the publication of results. It will also discuss the challenges that ZOU is facing in conducting examinations. It will finally emerge with some valuable practical suggestions on how ZOU can improve on its examination management and thereby achieve quality assurance in all its programmes. The investigation adopted the qualitative methodology and a case study design to generate data to address the questions which guided the study. The purposively sampled sample was drawn from ZOU’s National Centre, Bulawayo and Matabeleland North Regions. The sample consisted of manager -examinations, manager- quality control, chairpersons of departments from different faculties, programme leaders, programme coordinators, regional quality coordinators, regional administrators, and students who were in their second year of study. Face-to-face interviews were used to generate data from manager -examinations, manager- quality control, regional quality coordinators and regional administrators. Data from chairpersons of departments from different faculties, programme leaders, programme coordinators, second year students were generated through focus group discussions. Major findings were the management of examinations at ZOU enhances quality assurance, cited activities which contributed to quality assurance included setting of examination items for the item

  17. EXAMINATION MANAGEMENT AS A WAY OF ACHIEVING QUALITY ASSURANCE IN ODL INSTITUTIONS: The Case of Zimbabwe Open University

    Directory of Open Access Journals (Sweden)

    Onias MAFA

    2012-04-01

    Full Text Available An examination is an important component of any institution that educates people. It is a form of assessment used to measure the students’ understanding of the concepts and principles they would have learnt. Zimbabwe Open University, an Open and Distance Learning institution has been setting its own examinations for the academic programmes offered. Through examinations, ZOU students are encouraged to take an active role in analysing and questioning the things they would have learnt. This paper discusses the examinations management at ZOU with a special focus on the setting, administering, marking right up to the publication of results. It will also discuss the challenges that ZOU is facing in conducting examinations. It will finally emerge with some valuable practical suggestions on how ZOU can improve on its examination management and thereby achieve quality assurance in all its programmes. The investigation adopted the qualitative methodology and a case study design to generate data to address the questions which guided the study. The purposively sampled sample was drawn from ZOU’s National Centre, Bulawayo and Matabeleland North Regions. The sample consisted of manager -examinations, manager- quality control, chairpersons of departments from different faculties, programme leaders, programme coordinators, regional quality coordinators, regional administrators, and students who were in their second year of study. Face-to-face interviews were used to generate data from manager -examinations, manager- quality control, regional quality coordinators and regional administrators. Data from chairpersons of departments from different faculties, programme leaders, programme coordinators, second year students were generated through focus group discussions. Major findings were the management of examinations at ZOU enhances quality assurance, cited activities which contributed to quality assurance included setting of examination items for the item

  18. Low-temperature-grown InGaAs quantum wells for optical device applications

    Science.gov (United States)

    Juodawlkis, Paul William

    1999-11-01

    The large optical absorption and carrier-induced nonlinearities of semiconductor materials are useful for optical signal processing applications. For absorptive devices operating at ultrafast data rates (>100 Gb/s) or high optical intensities, it is necessary to reduce the intrinsic photo-excited carrier removal time. One method of achieving this reduction is to increase the nonradiative recombination rate through the controlled introduction of defects. In this thesis, we explore the use of low-temperature molecular-beam epitaxy (MBE) to introduce nonradiative recombination centers into InGaAs-based quantum-wells (QWs). The objectives of the thesis are: (i)to improve the understanding of the optoelectronic properties of low-temperature-grown (LTG) InGaAs/InAlAs QWs, and (ii)to assess the feasibility of using these materials for optical device applications in the 1.5-μm wavelength region. Time-resolved differential transmission measurements reveal that the nonlinear absorption recovery time in InGaAs/InAlAs QWs can be reduced from >100 ps to 0.6 ps through the combination of low-temperature growth (~250°C) and beryllium (Be) doping. The bandedge absorption slope and the nonlinear absorption cross- section are only diminished by factors of 2 to 3 relative to QWs grown at standard temperature (~500°C). The Be doping dependence of the recovery time and the residual electron density in the LTG-QWs can be mainly attributed to impurity-related compensation. Be doping also maintains the ultrafast recovery following thermal anneal. The recovery response results from fast electron- trapping followed by slow (>100 ps) trapped- electron/free-hole recombination. Detailed simulations of the nonlinear absorption saturation and recovery processes agree quantitatively with measured data and substantiate the importance of the photo-excitation wavelength on the observed recovery response. The absorption saturation model includes the competition between band-filling and band

  19. The necessary guidance on the application of JUSTIFICATION and ALARA by the nuclear authorities, using 'Accountability for Reasonableness' as a decision making process

    International Nuclear Information System (INIS)

    Full text: In all branches of law, but foremost in international nuclear law, the global economic system brings along a vast record of Soft Law covering General Principles and Standards. For a part we can find these Soft Law Principles and Standards back in the clothing of hard law, or in the licensing procedures, at the national level. The larger part however is never 'transposed' into national laws and especially the harmonization, the implementation and control of such Principles and Standards remain doubtful. In this paper the focus lies on JUSTIFICATION and ALARA, as the main nuclear safety principles, accepted world-wide. The regulatory guidance and demonstration of these Principles, indicating which (numerical) safety levels or safety objectives are mandatory and which are only guidance should be undertaken by the international regulators and authorities, but are often lacking. It is the aim of this paper to come up with a better procedural framework for a priority setting process by nuclear authorities. Establishing a fair process for priority setting is easier than agreeing on principles. We use the idea of 'Accountability for Reasonableness', developed in the field of Health Care Management. An ideal model of priority setting within the JUSTIFICATION/ALARA approach will need to specify what should be done (i.e. justified ethically) and how it can be done (i.e. based in empirical reality and on benchmarking), to reach optimal levels of nuclear safety. (author)

  20. COMPARATIVE PERSPECTIVES OF STUDY STRATEGIES AMONG HIGH AND LOW ACHIEVERS DISTANCE LEARNING STUDENTS

    Directory of Open Access Journals (Sweden)

    Muhammad Imran YOUSUF

    2009-07-01

    Full Text Available The main aim of this research is to better understand and draw perceptions of low and high achiever distance learners about their study patterns. The study indicates the areas where significant difference is found among low and high achievers of Allama Iqbal Open University, Pakistan through a self developed questionnaire covering their preferred study location, study times, number of hours spent on study, the difficulties affecting their study patterns and the organization of study strategies in comparative perspective. Greater difficulties were being faced by low achievers in their study. Increased difficulties were encountered by low achievers with study material, volume of study, self-motivation and other factors. There was no significant difference between low and high achievers for their study strategies of studying materials without taking notes and reading aloud. Greater low achievers attempted easy portions of their study material first and took notes simultaneously as compared to high achievers.

  1. Cognitive Training for Children: Effects on Inductive Reasoning, Deductive Reasoning, and Mathematics Achievement in an Australian School Setting

    Science.gov (United States)

    Barkl, Sophie; Porter, Amy; Ginns, Paul

    2012-01-01

    Inductive reasoning is a core cognitive process of fluid intelligence, predicting a variety of educational outcomes. The Cognitive Training for Children (CTC) program is an educational intervention designed to develop children's inductive reasoning skills, with previous investigations finding substantial effects of the program on both inductive…

  2. Helicobacter pylori infection and low serum pepsinogen I level as risk factors for gastric carcinoma

    Institute of Scientific and Technical Information of China (English)

    Arto Kokkola; Johanna Louhimo; Pauli Puolakkainen; Henrik Alfthan; Caj Haglund; Hilpi Rautelin

    2005-01-01

    AIM: To study whether examination of CagA antibodies could increase the odds ratio for gastric cancer in a casecontrol study, and how often other serum markers of gastric cancer risk could be found in Helicobacter pylorinegative patients.METHODS: H pylori CagA and parietal cell antibodies(PCAs), and serum pepsinogen Ⅰ (SPGI) levels were compared between patients with gastric cancer and controls who received endoscopic examination due to reasons other than gastrointestinal malignancy.RESULTS: The odds ratio (OR) for gastric cancer was2.9 (95% CI 1.4-5.8) in H pylori+ patients, and 2.4 (95%CI 1.2-4.9) in CagA+ patients. When results of H pylori and CagA antibodies were combined, OR increased to5.0 (95% CI 2.5-10.0). Furthermore, if cardia cancer patients were excluded, the OR increased to 6.8 (95% CI3.1-14.8). Among patients with a low SPGI level, the OR was 12.0 (95% CI 4.1-35.3). However, the risk was significant only in the older age group. The number of patients with low SPGI was significantly higher in H pylori-/CagA+ patients as compared to other cancer patients.CONCLUSION: Examination of both H pylori and CagA antibodies increases the OR for gastric cancer in our casecontrol study. CagA antibodies are important in detecting previous H pylori infection in advanced atrophic gastritis or cancer when spontaneous decline of H pylori antibodies occurs. SPGI may be helpful in screening elderly gastric cancer patients.

  3. Diet low in iodine as well as goitrogens (LILGD) enhanced radioiodine (I-131) uptake in treatment of differentiated thyroid cancer

    International Nuclear Information System (INIS)

    Full text: Low iodine diet (LID) is accepted as an adjuvant to post-thyroidectomy radioiodine therapy of differentiated thyroid cancer since it is held to enhance radioiodine uptake in thyroid remnants and thyroid cancer tissue. However, in the few clinical investigations performed only an indirect and weak evidence of a positive effect of the LID has been demonstrated. Also we had discouraging experience in the application of a strict LID using the same design as in the present study. We therefore decided to investigate the effect of a diet low in iodine as well as in goitrogens (LILGD). Methods: Six patients with differentiated thyroid cancer entered the study and they were their own control. After thyroid hormone withdrawal (TSH > 30 m U/L) and on regular diet a diagnostic whole body scan was performed 24 h after administration of 50 MBq (1,4 mCi) 123I. The day following diagnostic scan the patients were put on LILGD for 4 days prior and two days after radioiodine therapy. In LILGD beverages, fruits and vegetables containing flavonoids, glucosinolates, cyanides and thiocyanates were avoided and spices and smoking prohibited. Therapeutic radioiodine was administered one week after diagnostic procedures and in the morning after over-night fasting with an activity range of 3,7-5,4 GBq (100 -150 mCi) 131I. A 24-h therapeutic whole body scan and calculations of percentage uptake U(24) were performed. Diagnostic (basal) D U(24)% and subsequent therapeutic T U(24)% uptake were compared and expressed as therapeutic/diagnostic uptake ratios T/D U(24). Results: A significant increase in therapeutic versus diagnostic uptake T/D U(24) was observed (mean 2,53, median 2,30, range 1,40 - 4,46, p131I uptake in radio-ablation of normal and thyroid cancer tissue. (author)

  4. "I'm Not Doing as Well in This Class as I'd Like to": Exploring Achievement Motivation and Personality

    Science.gov (United States)

    Cole, James S.; Denzine, Gypsy M.

    2004-01-01

    This study looked at the relationship of explanatory style and self-systems (including self-esteem and self-efficacy) and the motivation (expectations for success and task value) of students who were dissatisfied with their performance in a particular class. One result is the confirmation that situated variables such as self-efficacy provide the…

  5. Low temperature processed metal-semiconductor-metal photodetectors on ZnSe/SI-GaAs (100)

    International Nuclear Information System (INIS)

    Low temperature (LT) processed ZnSe MSM photodetectors can be used for detecting gamma rays or X-rays using scintillation crystals in many space and medical applications. Metal-semiconductor-metal (MSM) photodetectors were fabricated on undoped ZnSe grown by molecular beam epitaxy (MBE) on semi-insulating (100) GaAs substrates. The MSM photodetectors consist of interdigitated metal fingers with 2 microm, 3 microm, and 4 microm spacing on one chip. Probimide and SiO2 thin films were deposited to aid the LT lift-off process before the pattern generation. An interdigitated structure was achieved by photolithography and reactive ion etching. Pd Schottky metal was deposited at a substrate temperature near 77 K using a lift-off technique. The LT metallization provides an improved interface between metal and semiconductor interface. Continuous wave signal to noise ratio (SNR) of 1.57 x 104 was obtained for 2 microm interdigitated photodetectors, operated under 180 nW optical power at a wavelength of 400 nm. The detectors showed good Dc saturation characteristics indicating a low surface recombination. Saturation current without illumination remained at around less than 1 pA for a ± 10 V biasing. Detectors exhibited linearity with light intensity and DC bias voltage suggesting no gain mechanism involved, and showed a high spectral responsivity (0.6 (A/W)) at a wavelength of 450 nm at 5 V applied bias

  6. Juxtaposing Math Self-Efficacy and Self-Concept as Predictors of Long-Term Achievement Outcomes

    Science.gov (United States)

    Parker, Philip David; Marsh, Herbert W.; Ciarrochi, Joseph; Marshall, Sarah; Abduljabbar, Adel Salah

    2014-01-01

    In this study, we tested the hypothesis that self-efficacy and self-concept reflect different underlying processes and both are critical to understanding long-term achievement outcomes. Although both types of self-belief are well established in educational psychology, research comparing and contrasting their relationship with achievement has been…

  7. Aptitude Tests Versus School Exams as Selection Tools for Higher Education and the Case for Assessing Educational Achievement in Context

    Science.gov (United States)

    Stringer, Neil

    2008-01-01

    Advocates of using a US-style SAT for university selection claim that it is fairer to applicants from disadvantaged backgrounds than achievement tests because it assesses potential, not achievement, and that it allows finer discrimination between top applicants than GCEs. The pros and cons of aptitude tests in principle are discussed, focusing on…

  8. The Intersections of Living-Learning Programs and Social Identity as Factors of Academic Achievement and Intellectual Engagement

    Science.gov (United States)

    Pasque, Penny A.; Murphy, Rena

    2005-01-01

    Findings from this study show that living-learning (LL) programs at a research institution in the Midwest have a series of positive outcomes for both academic achievement and intellectual engagement. Controlling for past academic achievement, socioeconomic status, and demographic characteristics, LL programs are predictors, albeit small…

  9. Parental Behaviors and Adolescents' Achievement Goals at the Beginning of Middle School: Emotional Problems as Potential Mediators

    Science.gov (United States)

    Duchesne, Stephane; Ratelle, Catherine

    2010-01-01

    Recent literature on the determinants of academic motivation has shown that parenting and emotions are central elements in understanding students' achievement goals. The authors of this study set out to examine the predictive relationship between parental behaviors during the last year of elementary school and adolescents' achievement goals at the…

  10. Comparing Dichotomous and Trichotomous Approaches to Achievement Goal Theory: An Example Using Motivational Regulations as Outcome Variables

    Science.gov (United States)

    Barkoukis, Vassilis; Ntoumanis, Nikos; Nikitaras, Nikitas

    2007-01-01

    Background: It is commonly assumed that there is conceptual equivalence between the task and ego achievement goals proposed by Nicholl's (1989) dichotomous achievement goal theory (Nicholls, 1989), and the mastery and performance approach goals advanced by Elliot's (1997) trichotomous hierarchical model of approach and avoidance achievement…

  11. Nature of Science and Scientific Inquiry as Contexts for the Learning of Science and Achievement of Scientific Literacy

    Science.gov (United States)

    Lederman, Norman G.; Lederman, Judith S.; Antink, Allison

    2013-01-01

    Although the reasons for concern about quality differ from nation to nation, the primary rallying point for science education reform is the perceived level of scientific literacy among a nation's populace. The essential nature of scientific literacy is that which influences students' decisions about personal and societal problems. Beyond this,…

  12. Highly transparent, low-haze, hybrid cellulose nanopaper as electrodes for flexible electronics

    Science.gov (United States)

    Xu, Xuezhu; Zhou, Jian; Jiang, Long; Lubineau, Gilles; Ng, Tienkhee; Ooi, Boon S.; Liao, Hsien-Yu; Shen, Chao; Chen, Long; Zhu, J. Y.

    2016-06-01

    Paper is an excellent candidate to replace plastics as a substrate for flexible electronics due to its low cost, renewability and flexibility. Cellulose nanopaper (CNP), a new type of paper made of nanosized cellulose fibers, is a promising substrate material for transparent and flexible electrodes due to its potentially high transparency and high mechanical strength. Although CNP substrates can achieve high transparency, they are still characterized by high diffuse transmittance and small direct transmittance, resulting in high optical haze of the substrates. In this study, we proposed a simple methodology for large-scale production of high-transparency, low-haze CNP comprising both long cellulose nanofibrils (CNFs) and short cellulose nanocrystals (CNCs). By varying the CNC/CNF ratio in the hybrid CNP, we could tailor its total transmittance, direct transmittance and diffuse transmittance. By increasing the CNC content, the optical haze of the hybrid CNP could be decreased and its transparency could be increased. The direct transmittance and optical haze of the CNP were 75.1% and 10.0%, respectively, greatly improved from the values of previously reported CNP (31.1% and 62.0%, respectively). Transparent, flexible electrodes were fabricated by coating the hybrid CNP with silver nanowires (AgNWs). The electrodes showed a low sheet resistance (minimum 1.2 Ω sq-1) and a high total transmittance (maximum of 82.5%). The electrodes were used to make a light emitting diode (LED) assembly to demonstrate their potential use in flexible displays.Paper is an excellent candidate to replace plastics as a substrate for flexible electronics due to its low cost, renewability and flexibility. Cellulose nanopaper (CNP), a new type of paper made of nanosized cellulose fibers, is a promising substrate material for transparent and flexible electrodes due to its potentially high transparency and high mechanical strength. Although CNP substrates can achieve high transparency, they are

  13. International Space Station as a Platform for Exploration Beyond Low Earth Orbit

    Science.gov (United States)

    Raftery, Michael; Woodcock, Gordon

    2010-01-01

    The International Space Station (ISS) has established a new model for the achievement of the most difficult engineering goals in space: international collaboration at the program level with competition at the level of technology. This strategic shift in management approach provides long term program stability while still allowing for the flexible evolution of technology needs and capabilities. Both commercial and government sponsored technology developments are well supported in this management model. ISS also provides a physical platform for development and demonstration of the systems needed for missions beyond low earth orbit. These new systems at the leading edge of technology require operational exercise in the unforgiving environment of space before they can be trusted for long duration missions. Systems and resources needed for expeditions can be aggregated and thoroughly tested at ISS before departure thus providing wide operational flexibility and the best assurance of mission success. We will describe representative mission profiles showing how ISS can support exploration missions to the Moon, Mars, asteroids and other potential destinations. Example missions would include humans to lunar surface and return, and humans to Mars orbit as well as Mars surface and return. ISS benefits include: international access from all major launch sites; an assembly location with crew and tools that could help prepare departing expeditions that involve more than one launch; a parking place for reusable vehicles; and the potential to add a propellant depot.

  14. Comparing Self-Regulatory and Early Academic Skills as Predictors of Later Math, Reading, and Science Elementary School Achievement

    Science.gov (United States)

    Murrah, William M., III

    The achievement score gaps between advantaged and disadvantaged children at school entry is a major problem in education today. Identifying the skills critical for school readiness is an important step in developing interventions aimed at addressing these score gaps. The purpose of this study is to compare a number of school readiness skills with an eye toward finding out which are the best predictors of later academic achievement in math, reading, and science. The predictors were early reading, math, general knowledge, socioemotional skills, and motor skills. Data were obtained from the Early Childhood Longitudinal Study of 1998 (NCES, 1998) database. While controlling for an extensive set of family characteristics, predictions were made across five years - from the end of kindergarten to the end of fifth grade. Consistent with current findings, reading and math skills predicted later achievement. Interestingly, general knowledge, attention, and fine motor skills also proved to be important predictors of later academic achievement, but socioemotional skills were not. The findings were interpreted from a neurobiological perspective involving the development of self-regulation. These school entry skills are used to predict later achievement in reading, math, and science. I argued that in addition to acquiring early academic knowledge, children need to regulate the use of this knowledge to meet academic goals.

  15. Nature of Science and Scientific Inquiry as Contexts for the Learning of Science and Achievement of Scientific Literacy

    OpenAIRE

    Lederman, Norman G.; Lederman, Judith S.; Antink, Allison

    2013-01-01

    Although the reasons for concern about quality differ from nation to nation, the primary rallying point for science education reform is the perceived level of scientific literacy among a nation’s populace. The essential nature of scientific literacy is that which influences students’ decisions about personal and societal problems. Beyond this, however, educators work to influence students’ ability to view science through a more holistic lens. Examining the philosophy, history, and socio...

  16. Academic Achievements, Behavioral Problems, and Loneliness as Predictors of Social Skills among Students with and without Learning Disorders

    Science.gov (United States)

    Zach, Sima; Yazdi-Ugav, Orly; Zeev, Aviva

    2016-01-01

    This study aimed to examine to what extent academic achievements, learning disorders, behavior problems and loneliness explain the variance of students' social skills. The differences between students diagnosed with learning disorders and students without learning disorders in all four variables were examined. Participants were 733 elementary…

  17. School Librarian Staffing Levels and Student Achievement as Represented in 2006-2009 Kansas Annual Yearly Progress Data

    Science.gov (United States)

    Dow, Mirah J.; McMahon-Lakin, Jacqueline

    2012-01-01

    To address the presence or absence of school librarians in Kansas public schools, a study using analysis of covariance (ANCOVA) was designed to investigate staffing levels for library media specialists (LMSs), the label used for school librarians in licensed-personnel data in Kansas, and student achievement at the school level. Five subject areas…

  18. A Study of Motivation and Other Factors as Relating to Course Achievement in Introductory College Biology, Chemistry, and Physics.

    Science.gov (United States)

    Pridmore, Brooke M.; Halyard, Rebecca A.

    Results of a preliminary study that examined various factors relating to achievement in introductory level biology, chemistry, and physics classes at a public junior college are presented. Background variables, including age, sex, college major, grade point average, SAT-Verbal and SAT-Quantitative, and the sixteen-part scores of Academic…

  19. Neurofeedback as an Intervention to Improve Reading Achievement in Students with Attention- Deficit/Hyperactivity Disorder, Inattentive Subtype

    Science.gov (United States)

    La Marca, Jeffry P.; O'Connor, Rollanda E.

    2016-01-01

    Research consistently demonstrates that attention deficits have a deleterious effect on academic achievement. Impairments in attention, and not hyperactivity/impulsivity, are associated with learning difficulties and academic problems in students with attention-deficit/hyperactivity disorder (ADHD). To date, most studies have focused on symptoms…

  20. Conscientiousness, Achievement Striving, and Intelligence as Performance Predictors in a Sample of German Psychology Students: Always a Linear Relationship?

    Science.gov (United States)

    Ziegler, Matthias; Knogler, Maximilian; Buhner, Markus

    2009-01-01

    Studies on the interface between cognitive ability (intelligence) and personality in the prediction of academic performance have yielded mixed results so far. Especially an interaction between conscientiousness (and its facet achievement striving) and intelligence has been investigated. The hypothesis is that conscientiousness enhances the impact…

  1. Partnership-Ready Schools: Building Systems and Mindsets for the Achievement Schools to Receive and Utilize Community Organizations as Partners in Student Success

    OpenAIRE

    Sanders, Ansel

    2015-01-01

    Over the last decade, the call for schools to leverage partnerships with community organizations as a means to provide services that will mitigate the effects of poverty in the pursuit of achieving ambitious academic outcomes has gained momentum. The Achievement Schools, a network of five neighborhood schools serving students in Memphis’ Frayser community, has prioritized the development of partnerships as a lever to turn around the academic performance of its schools by ensuring students’ no...

  2. High performance 1.3μm InAs/GaAs quantum dot lasers with low threshold current and negative characteristic temperature

    Science.gov (United States)

    Liu, H. Y.; Badcock, T. J.; Groom, K. M.; Hopkinson, M.; Gutiérrez, M.; Childs, D. T.; Jin, C.; Hogg, R. A.; Sellers, I. R.; Mowbray, D. J.; Skolnick, M. S.; Beanland, R.; Robbins, D. J.

    2006-04-01

    A high-growth-temperature step used for the GaAs spacer layer is shown to significantly improve the performance of 1.3-μm multilayer InAs/GaAs quantum-dot (QD) lasers. The high-growth-temperature spacer layer inhibits threading dislocation formation, resulting in enhanced electrical and optical characteristics and hence improved laser performance. The combination of high-growth-temperature GaAs spacer layers and high-reflectivity (HR) coated facets has been utilized to further reduce the threshold current and threshold current density (J th) for 1.3-μm InAs/GaAs QD lasers. Very low continuous-wave room-temperature threshold current of 1.5 mA and a threshold current density of 18.8 A/cm2 are achieved for a 3-layer device with a 1-mm long HR/HR cavity. For a 2-mm cavity the continuous-wave threshold current density is as low as 17 A/cm2 at room temperature for an HR/HR device. An output power as high as 100 mW is obtained for a device with HR/cleaved facets. The high-growth-temperature spacer layers have only a relatively small effect on the temperature stability of the threshold current above room temperature. To further increase the characteristic temperature (T 0) of the QD lasers, 1.3-μm InAs/GaAs QD lasers incorporating p-type modulation doping have been grown and studied. A negative T 0 and J th of 48 A/cm -2 at room temperature have been obtained by combining the high-growth-temperature GaAs spacer layers with the p-type modulation doping of the QDs.

  3. The effectiveness of walking as an intervention for low back pain: a systematic review

    OpenAIRE

    Hendrick, P; Te Wake, A. M.; Tikkisetty, A. S.; Wulff, L.; Yap, C.; Milosavljevic, S.

    2010-01-01

    As current low back pain (LBP) guidelines do not specifically advocate walking as an intervention, this review has explored for the effectiveness of walking in managing acute and chronic LBP. CINAHL, Medline, AMED, EMBASE, PubMed, Cochrane and Scopus databases, as well as a hand search of reference lists of retrieved articles, were searched. The search was restricted to studies in the English language. Studies were included when walking was identified as an intervention. Four studies met incl...

  4. Characterization of Femtosecond Low-Temperature-Grown GaAs Photoconductive Switch

    Institute of Scientific and Technical Information of China (English)

    林位株; 刘智刚; 廖睿; 张海潮; 郭冰; 文锦辉; 赖天树

    2002-01-01

    A photoconductive response time, as short as 350 fs, of a low-temperature-grown GaAs (LT-GaAs) micro-coplanar photoconductive switch has been measured and modelled to the ultrafast trapping of the photoexcited carriers in LT-GaAs. The coherent interference of the pump and probe pulses results in a narrow spike photocurrent autocorrelation signal which maps the femtosecond optical pulses.

  5. Highest achievable detection range for SPR based sensors using gallium phosphide (GaP) as a substrate: a theoretical study

    Science.gov (United States)

    Verma, Rajneesh K.; Mishra, Akhilesh K.

    2016-06-01

    In the present study, we have theoretically modelled a surface plasmon resonance (SPR) based sensing chip utilizing a prism made up of gallium phosphidee. It has been found in the study that a large range of refractive index starting from the gaseous medium to highly concentrated liquids can be sensed by using a single chip in the visible region of the spectrum. The variation of the sensitivity as well as detection accuracy with sensing region refractive index has been analyzed in detail. The large value of the sensitivity along with the large dynamic range is the advantageous feature of the present sensing probe.

  6. Classroom quality as a predictor of first graders' time in non-instructional activities and literacy achievement.

    Science.gov (United States)

    McLean, Leigh; Sparapani, Nicole; Toste, Jessica R; Connor, Carol McDonald

    2016-06-01

    This study investigated how quality of the classroom learning environment influenced first grade students' (n=533) time spent in two non-instructional classroom activities (off-task and in transition) and their subsequent literacy outcomes. Hierarchical linear modeling revealed that higher classroom quality was related to higher student performance in reading comprehension and expressive vocabulary. Further, classroom quality predicted the amount of time students spent off-task and in transitions in the classroom, with slopes of change across the year particularly impacted. Mediation effects were detected in the case of expressive vocabulary such that the influence of classroom quality on students' achievement operated through students' time spent in these non-instructional activities. Results highlight the importance of overall classroom quality to how students navigate the classroom environment during learning opportunities, with subsequent literacy achievement impacted. Implications for policy and educational practices are discussed. PMID:27268569

  7. Neighborhood Ethnic Density as an Explanation for the Academic Achievement of Ethnic Minority Youth Placed in Neighborhood Disadvantage

    OpenAIRE

    Madyun, Na'im Dr.; Lee, Moosung Dr.

    2010-01-01

    The underachievement of ethnic minority youth from disadvantaged neighborhoods is a pervasive educational issue this nation is facing. Based on an ecological perspective, we examined the contextual effects of neighborhood ethnic density and neighborhood disadvantage on the academic achievement of Hmong immigrant youths. Utilizing hierarchical linear modeling techniques in analyzing 3,185 Hmong and White students (for comparisons) across 79 neighborhoods, we found when we controlled for studen...

  8. Babesia and its hosts: adaptation to long-lasting interactions as a way to achieve efficient transmission

    OpenAIRE

    Chauvin, Alain; Moreau, Emmanuelle; Bonnet, Sarah; Plantard, Olivier; Malandrin, Laurence

    2009-01-01

    Babesia, the causal agent of babesiosis, are tick-borne apicomplexan protozoa. True babesiae (Babesia genus sensu stricto) are biologically characterized by direct development in erythrocytes and by transovarial transmission in the tick. A large number of true Babesia species have been described in various vertebrate and tick hosts. This review presents the genus then discusses specific adaptations of Babesia spp. to their hosts to achieve efficient transmission. The main adaptations lead to ...

  9. Language and academic achievement: Perspectives on the potential role of indigenous African languages as a lingua academica

    OpenAIRE

    Mbulungeni Madiba

    2013-01-01

    Although research literature abounds with studies that show the importance of language for academic achievement, the potential role of indigenous African languages in the educational sector in South Africa has not been adequately appraised or appreciated. Accordingly, ambivalence is still rife among parents, teachers, learners and government about the use of these languages for academic purposes. This ambivalence is evident from the existing national language education policies, school langua...

  10. Evaluation of an English as a Second Language Program to Identify Primary Indicators of Learning Disabilities that Impede Student Achievement

    Science.gov (United States)

    Campbell, Joan-Yvette

    2009-01-01

    The study is an evaluation of an English as a Second Language (ESL) program at a southeastern technical college. Thousands of adults who enroll in ESL programs are individuals who appear to be intelligent. They have worked diligently for a year or more to learn to speak, read, write, listen and improve English comprehension skills. However, some…

  11. The Relationship between Anxiety and Attitude of Students Learning Turkish as a Foreign Language and Their Achievement on Target Language

    Science.gov (United States)

    Gocer, Ali

    2014-01-01

    The purpose of this study is to assess the anxiety connected with target language of the high school students learning Turkish as a foreign language. In this study, descriptive relational screening model was used. Two scales were used for collecting data. First scale was FLCAS-Foreign Language Classroom Anxiety Scale; it was developed by Horwitz…

  12. Learning about Teaching the Extracurricular Topic of Nanotechnology as a Vehicle for Achieving a Sustainable Change in Science Education

    Science.gov (United States)

    Blonder, Ron; Mamlok-Naaman, Rachel

    2016-01-01

    This study focused on teachers' transfer of a variety of teaching methods from a teaching module on nanotechnology, which is an example of a topic outside the science curriculum, to teaching topics that are part of the chemistry curriculum. Nanotechnology is outside the science curriculum, but it was used in this study as a means to carry out a…

  13. Positive Affect and Negative Affect as Modulators of Cognition and Motivation: The Rediscovery of Affect in Achievement Goal Theory

    Science.gov (United States)

    Bjornebekk, Gunnar

    2008-01-01

    A central hypothesis of classical motivation theory is that affect underlies motivation and its behavioural manifestations. However, this has been largely ignored in the past 30 years because social cognitivism has been the dominant theory. As a result, studies have concentrated on social cognitive processes when analysing those factors that…

  14. Views from the Field: Conservation Educators' and Practitioners' Perceptions of Education as a Strategy for Achieving Conservation Outcomes

    Science.gov (United States)

    Ardoin, Nicole M.; Heimlich, Joe E.

    2013-01-01

    This article presents data from a mixed-methods study that collected data through surveys (n = 656), interviews (n = 15), and discussion groups (n = 75) to explore the use of social strategies such as education and outreach by non-governmental organizations and government agencies to reach outcomes related to biodiversity conservation and resource…

  15. Reasons Low-Income Parents Offer Snacks to Children: How Feeding Rationale Influences Snack Frequency and Adherence to Dietary Recommendations

    Directory of Open Access Journals (Sweden)

    Rachel E. Blaine

    2015-07-01

    Full Text Available Although American children snack more than ever before, the parental role in promoting snacking is not well understood. In 2012–2013 at baseline in an intervention study to prevent childhood obesity in low-income Massachusetts communities, n = 271 parents of children aged 2–12 years completed surveys regarding nutritive and non-nutritive reasons they offered children snacks, demographics, and dietary factors. An analysis of variance demonstrated that parents reported offering snacks (mean/week; standard deviation (SD for nutritive reasons like promoting growth (x̄ = 2.5; SD 2.2 or satisfying hunger (x̄ = 2.4; SD 2.1 almost twice as often as non-nutritive reasons like keeping a child quiet (x̄ = 0.7; SD 1.5 or celebrating events/holidays (x̄ = 0.8; SD 1.1. Parents reported giving young children (2–5 years more snacks to reward behavior (1.9 vs. 1.1, p < 0.001, keep quiet (1.0 vs. 0.5, p < 0.001, and celebrate achievements (1.7 vs. 1.0, p < 0.001 than parents of older children (6–12 years. Multivariable logistic regression models were used to obtain adjusted odds ratios, which indicated reduced child adherence to dietary recommendations when parents offered snacks to reward behavior (Odds Ratio (OR = 0.83; 95% Confidence Interval (CI 0.70–0.99, celebrate events/holidays (OR = 0.72; 95% CI 0.52–0.99, or achievements (OR = 0.82; 95% CI 0.68–0.98. Parental intentions around child snacking are likely important targets for obesity prevention efforts.

  16. NANOPARTICLES OF TUNGSTEN AS LOW-COST MONOMETALLIC CATALYST FOR SELECTIVE HYDROGENATION OF 3-HEXYNE

    Directory of Open Access Journals (Sweden)

    María Juliana Maccarrone

    2016-01-01

    Full Text Available Low-cost tungsten monometallic catalysts containing variable amounts of metal (4.5, 7.1 and 8.5%W were prepared by impregnating alumina with ammonium metatungstate as an inexpensive precursor. The catalysts were characterized using ICP, XPS, XRD, TPR and hydrogen chemisorption. These techniques revealed mainly WO3-Al2O3 (W6+ species on the surface. The effects of the content of W nanoparticles and reaction temperature on activity and selectivity for the partial hydrogenation of 3-hexyne, a non-terminal alkyne, were assessed under moderate conditions of temperature and pressure. The monometallic catalysts prepared were found to be active and stereoselective for the production of (Z -3-hexene, had the following order: 7.1WN/A > 8.5 WN/A ≥ 4.5 WN/A. Additionally, the performance of the synthesized xWN/A catalysts exhibited high sensitivity to temperature variation. In all cases, the maximum 3-hexyne total conversion and selectivity was achieved at 323 K. The performance of the catalysts was considered to be a consequence of two phenomena: a the electronic effects, related to the high charge of W (+6, causing an intensive dipole moment in the hydrogen molecule (van der Waals forces and leading to heterolytic bond rupture; the H+ and H- species generated approach a 3-hexyne adsorbate molecule and cause heterolytic rupture of the C≡C bond into C- = C+; and b steric effects related to the high concentration of WO3 on 8.5WN/A that block the Al2O3 support. Catalyst deactivation was detected, starting at about 50 min of reaction time. Electrodeficient W6+ species are responsible for the formation of green oil at the surface level, blocking pores and active sites of the catalyst, particularly at low reaction temperatures (293 and 303 K. The resulting best catalyst, 7.1WN/A, has low fabrication cost and high selectivity for (Z -3-hexene (94% at 323 K. This selectivity is comparable to that of the classical and more expensive industrial Lindlar catalyst

  17. Progress on the Low-Latency Inspiral Gravitational Wave Detection algorithm known as SPIIR

    OpenAIRE

    Hooper, S.; Wen, L; Hanna, C.; Cannon, K; Keppel, D.; Blair, D; Chung, S; Singer, L.; Chen, Y

    2012-01-01

    Low-latency event triggers to signify the presence of gravitational waves from coalescing binaries will be required to make prompt electromagnetic follow-up observations of electromagnetic counterparts. We present the recent progress made on implementing the time-domain low-latency detection algorithm known as summed parallel infinite impulse response (SPIIR) filtering into a real gravitational wave search pipeline.

  18. Low-water activity foods: increased concern as vehicles of foodborne pathogens

    NARCIS (Netherlands)

    Beuchat, L.R.; Komitopoulou, E.; Beckers, H.; Betts, R.P.; Bourdichon, F.; Fanning, S.; Joosten, H.M.L.J.; Kuile, ter B.H.

    2013-01-01

    Foods and food ingredients with low water activity (aw) have been implicated with increased frequency in recent years as vehicles for pathogens that have caused outbreaks of illnesses. Some of these foodborne pathogens can survive for several months, even years, in low-aw foods and in dry food proce

  19. Academic Attitudes of High Achieving and Low Achieving Academically Able Black Male Adolescents.

    Science.gov (United States)

    Trotter, John Rhodes

    1981-01-01

    In order to identify the relationships between the attitudes and perceptions of peer pressure and the academic achievement of academically able male adolescents, this study compares the school attitudes of high achieving and low achieving Black male youth. (EF)

  20. Ultra-low dark current InGaAs technology for focal plane arrays for low-light level visible-shortwave infrared imaging

    Science.gov (United States)

    Onat, Bora M.; Huang, Wei; Masaun, Navneet; Lange, Michael; Ettenberg, Martin H.; Dries, Christopher

    2007-04-01

    Under the DARPA Photon Counting Arrays (PCAR) program we have investigated technologies to reduce the overall noise level in InGaAs based imagers for identifying a man at 100m under low-light level imaging conditions. We report the results of our experiments comprising of 15 InGaAs wafers that were utilized to investigate lowering dark current in photodiode arrays. As a result of these experiments, we have achieved an ultra low dark current of 2nA/cm2 through technological advances in InGaAs detector design, epitaxial growth, and processing at a temperature of +12.3 degrees C. The InGaAs photodiode array was hybridized to a low noise readout integrated circuit, also developed under this program. The focal plane array (FPA) achieves very high sensitivity in the shortwave infrared bands in addition to the visible response added via substrate removal process post hybridization. Based on our current room-temperature stabilized SWIR camera platform, these imagers enable a full day-night imaging capability and are responsive to currently fielded covert laser designators, illuminators, and rangefinders. In addition, improved haze penetration in the SWIR compared to the visible provides enhanced clarity in the imagery of a scene. In this paper we show the results of our dark current studies as well as FPA characterization of the camera built under this program.

  1. Low temperature transport in p-doped InAs nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Upadhyay, S.; Jespersen, T. S.; Madsen, M. H.; Krogstrup, P.; Nygård, J. [Center for Quantum Devices and Nano-Science Center, Niels Bohr Institute, University of Copenhagen, Universitetsparken 5, DK-2100 Copenhagen (Denmark)

    2013-10-14

    We present low temperature electrical measurements of p-type Indium Arsenide nanowires grown via molecular beam epitaxy using Beryllium as a dopant. Growth of p-type wires without stacking faults is demonstrated. Devices in field-effect geometries exhibit ambipolar behavior, and the temperature dependence of electron and hole field effect mobilities are extracted. At low temperatures, we observe reproducible conductance fluctuations as a result of quantum interference, and magnetoconductance data show weak antilocalization.

  2. FRANCHISING AS A MEANS OF ACHIEVING INTERNATIONALIZATION: RESEARCH PROPOSITIONS FROM A MULTIPLE CASE STUDY OF BRAZILIAN FASHION RETAILERS

    OpenAIRE

    Victor Manoel Cunha de Almeida; Felipe Mendes Borini; Thiago Cruz Silveira; Ilan Avrichir

    2015-01-01

    According to Brazilian Franchising Association, the number of Brazilian franchises has grown 300% in the last ten years, but only 3% of Brazilian franchises operate in foreign markets, so the opportunity to internationalization is strong. Aiming to get a better understanding of possible distinctive features of Brazilian retail internationalization, this paper explores the determinants of franchising as the choice of internationalization entry mode by Brazilian’s firms in the fashion apparel s...

  3. Ohmic contact formation process on low n-type gallium arsenide (GaAs) using indium gallium zinc oxide (IGZO)

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Seong-Uk [Samsung-SKKU Graphene Center and School of Electronics and Electrical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Product and Test Engineering Team, System LSI Division, Samsung Electronics Co., Ltd, Yongin 446-711 (Korea, Republic of); Jung, Woo-Shik [Department of Electrical Engineering, Stanford University, Stanford, CA 94305 (United States); Lee, In-Yeal; Jung, Hyun-Wook; Kim, Gil-Ho [Samsung-SKKU Graphene Center and School of Electronics and Electrical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Park, Jin-Hong, E-mail: jhpark9@skku.edu [Samsung-SKKU Graphene Center and School of Electronics and Electrical Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2014-02-01

    Highlights: • We propose a method to fabricate non-gold Ohmic contact on low n-type GaAs with IGZO. • 0.15 A/cm{sup 2} on-current and 1.5 on/off-current ratio are achieved in the junction. • InAs and InGaAs formed by this process decrease an electron barrier height. • Traps generated by diffused O atoms also induce a trap-assisted tunneling phenomenon. - Abstract: Here, an excellent non-gold Ohmic contact on low n-type GaAs is demonstrated by using indium gallium zinc oxide and investigating through time of flight-secondary ion mass spectrometry, X-ray photoelectron spectroscopy, transmission electron microscopy, J–V measurement, and H [enthalpy], S [entropy], Cp [heat capacity] chemistry simulation. In is diffused through GaAs during annealing and reacts with As, forming InAs and InGaAs phases with lower energy bandgap. As a result, it decreases the electron barrier height, eventually increasing the reverse current. In addition, traps generated by diffused O atoms induce a trap-assisted tunneling phenomenon, increasing generation current and subsequently the reverse current. Therefore, an excellent Ohmic contact with 0.15 A/cm{sup 2} on-current density and 1.5 on/off-current ratio is achieved on n-type GaAs.

  4. Ohmic contact formation process on low n-type gallium arsenide (GaAs) using indium gallium zinc oxide (IGZO)

    International Nuclear Information System (INIS)

    Highlights: • We propose a method to fabricate non-gold Ohmic contact on low n-type GaAs with IGZO. • 0.15 A/cm2 on-current and 1.5 on/off-current ratio are achieved in the junction. • InAs and InGaAs formed by this process decrease an electron barrier height. • Traps generated by diffused O atoms also induce a trap-assisted tunneling phenomenon. - Abstract: Here, an excellent non-gold Ohmic contact on low n-type GaAs is demonstrated by using indium gallium zinc oxide and investigating through time of flight-secondary ion mass spectrometry, X-ray photoelectron spectroscopy, transmission electron microscopy, J–V measurement, and H [enthalpy], S [entropy], Cp [heat capacity] chemistry simulation. In is diffused through GaAs during annealing and reacts with As, forming InAs and InGaAs phases with lower energy bandgap. As a result, it decreases the electron barrier height, eventually increasing the reverse current. In addition, traps generated by diffused O atoms induce a trap-assisted tunneling phenomenon, increasing generation current and subsequently the reverse current. Therefore, an excellent Ohmic contact with 0.15 A/cm2 on-current density and 1.5 on/off-current ratio is achieved on n-type GaAs

  5. Onset of ferromagnetism in low-doped GaMnAs

    OpenAIRE

    Sheu, B. L.; Myers, R. C.; Tang, J. -M.; Samarth, N.; Awschalom, D. D.; Schiffer, P.; Flatté, M. E.

    2007-01-01

    We develop a quantitatively predictive theory for impurity-band ferromagnetism in the low-doping regime of GaMnAs and compare with experimental measurements of a series of samples whose compositions span the transition from paramagnetic insulating to ferromagnetic conducting behavior. The theoretical Curie temperatures depend sensitively on the local fluctuations in the Mn-hole binding energy, which originates from disorder in the Mn distribution as well as the presence of As antisite defects...

  6. 100 nm AlSb/InAs HEMT for Ultra-Low-Power Consumption, Low-Noise Applications

    Directory of Open Access Journals (Sweden)

    Cyrille Gardès

    2014-01-01

    Full Text Available We report on high frequency (HF and noise performances of AlSb/InAs high electron mobility transistor (HEMT with 100 nm gate length at room temperature in low-power regime. Extrinsic cut-off frequencies fT/fmax of 100/125 GHz together with minimum noise figure NFmin=0.5 dB and associated gain Gass=12 dB at 12 GHz have been obtained at drain bias of only 80 mV, corresponding to 4 mW/mm DC power dissipation. This demonstrates the great ability of AlSb/InAs HEMT for high-frequency operation combined with low-noise performances in ultra-low-power regime.

  7. Charge collection efficiency of GaAs detectors studied with low-energy heavy charged particles

    CERN Document Server

    Bates, R; Linhart, V; O'Shea, V; Pospísil, S; Raine, C; Smith, K; Sinor, M; Wilhelm, I

    1999-01-01

    Epitaxially grown GaAs layers have recently been produced with sufficient thickness and low enough free carrier concentration to permit their use as radiation detectors. Initial tests have shown that the epi-material behaves as a classical semiconductor as the depletion behaviour follows the square root dependency on the applied bias. This article presents the results of measurements of the growth of the active depletion depth with increasing bias using low-energy protons and alpha particles as probes for various depths and their comparison to values extrapolated from capacitance measurements. From the proton and alpha particle spectroscopic measurements, an active depth of detector material that collects 100% of the charge generated inside it was determined. The consistency of these results with independent capacitance measurements supports the idea that the GaAs epi-material behaves as a classical semiconductor. (author)

  8. Elements of product service systems as a potential to achieve a sustainable development: bibliometry and content analysis

    Directory of Open Access Journals (Sweden)

    Rafael Ariente Neto

    2014-08-01

    Full Text Available The concept of product-service systems (PSS is presented as an innovative strategy when offering products and services. It aims at for minimizing environmental impacts through sustainable business models. This study aims to identify which potentialities can be explored with regard to the elements of a PSS in a configuration that favor to offer answers on sustainable issues. To do so, the literature was analyzed by a structured process of bibliographic review. Among the results, three aspects are highlighted: (i the wideness of product concept to add services through PSS life-cycle, (ii the configuration of infra-structure to support a PSS by establishing the necessary communication relatively to logistics services. Finally, the net of actors should be explored to obtain organizational proposals that contribute to PSS performance.

  9. FRANCHISING AS A MEANS OF ACHIEVING INTERNATIONALIZATION: RESEARCH PROPOSITIONS FROM A MULTIPLE CASE STUDY OF BRAZILIAN FASHION RETAILERS

    Directory of Open Access Journals (Sweden)

    Victor Manoel Cunha de Almeida

    2015-12-01

    Full Text Available According to Brazilian Franchising Association, the number of Brazilian franchises has grown 300% in the last ten years, but only 3% of Brazilian franchises operate in foreign markets, so the opportunity to internationalization is strong. Aiming to get a better understanding of possible distinctive features of Brazilian retail internationalization, this paper explores the determinants of franchising as the choice of internationalization entry mode by Brazilian’s firms in the fashion apparel sector. The multiple-case study was the approach used. The study resulted in eleven research propositions. Results show that government or trade organizations support, geographic distance, political and economic risk may not be determinant to internationalization. However cultural proximity and relationship with local partners can be determinant to internationalization. Moreover, brands that cater to a very specific segment and that their value proposition is closely linked to intangible factors may face problems in expanding to culturally distant international environments.

  10. Steric repulsion as a way to achieve the required stability for the preparation of ionic liquid-based ferrofluids.

    Science.gov (United States)

    Rodríguez-Arco, Laura; López-López, Modesto T; González-Caballero, Fernando; Durán, Juan D G

    2011-05-01

    With this work we would like to emphasize the necessity of steric repulsion to stabilize novel ionic liquid-based ferrofluids. For this purpose, we prepared a suspension of magnetite nanoparticles coated with a double layer of oleic acid, dispersed in 1-ethyl-3-methylimidazolium ethylsulphate ([EMIM][EtSO(4)]). For comparison, a suspension of bare magnetite nanoparticles in [EMIM][EtSO(4)] was also prepared. The stability of these suspensions was checked by magnetic sedimentation and centrifugation processes. Furthermore, their yield stress was measured as a function of the applied magnetic field, which gave additional information on their stability. The results of these experiments showed that the suspension of bare nanoparticles was rather unstable, whereas the suspension of double layer coated nanoparticles gave rise to a true (stable) ferrofluid. PMID:21345446

  11. Assessing the suitability of GIS as an aid for Location Scouting in Low-Budget Filmmaking

    OpenAIRE

    Fuller, Callum

    2010-01-01

    The purpose of this analysis was to assess the suitability of GIS as an aid for location scouting in low-budget filmmaking, with Edinburgh serving as the target area. The main aspect of the project was to create a web based map service to act as a guide for the service user, rather than be a definitive resource. The key to satisfying the target audience of low-budget filmmakers was to gather their input to inform user requirements. Similar services within Edinburgh were researched and no s...

  12. A low power 2.5-5 GHz low-noise amplifier using 0.5-μm GaAs pHEMT technology

    International Nuclear Information System (INIS)

    A two-stage 2.5-5 GHz monolithic low-noise amplifier (LNA) has been fabricated using 0.5-μm enhanced mode AlGaAs/GaAs pHEMT technology. To achieve wide operation bandwidth and low noise figure, the proposed LNA uses a wideband matching network and a negative feedback technique. Measured results from 2.5 to 5 GHz demonstrate a minimum of 2.4-dB noise figure and 17-dB gain. The input and output return loss exceeded −10-dB across the band. The power consumption of this LNA is 33 mW. According to the author's knowledge, this is the lowest power consumption LNA fabricated in 0.5-μm AlGaAs/GaAs pHEMT with the comparable performance.

  13. A low power 2.5-5 GHz low-noise amplifier using 0.5-μm GaAs pHEMT technology

    Institute of Scientific and Technical Information of China (English)

    Peng Yangyang; Lu Kejie; Sui Wenquan

    2012-01-01

    A two-stage 2.5-5 GHz monolithic low-noise amplifier (LNA) has been fabricated using 0.5-μm enhanced mode AlGaAs/GaAs pHEMT technology.To achieve wide operation bandwidth and low noise figure,the proposed LNA uses a wideband matching network and a negative feedback technique.Measured results from 2.5 to 5 GHz demonstrate a minimum of 2.4-dB noise figure and 17-dB gain.The input and output return loss exceeded-10-dB across the band.The Power consumption of this LNA is 33 mW.According to the author's knowledge,this is the lowest power consumption LNA fabricated in 0.5-μm A1GaAs/GaAs pHEMT with the comparable performance.

  14. The relationship between reading and science achievement of fifth grade students as measured by the Texas Assessment of Knowledge and Skills test

    Science.gov (United States)

    Ratliff, Charles H.

    The purpose of this study was to examine the relationship between the reading and science achievement of upper elementary students as assessed by the Texas Assessment of Knowledge and Skills (TAKS) test in the Region One Educational Service Center area in the 2006 testing cycle. A correlational research design was utilized to study these relationships. The participants were those fifth grade students who had been administered both the English versions of the reading and science TAKS tests (N = 6,281) or both the Spanish versions of the reading and science TAKS tests (N = 491). Bivariate analyses using the Pearson product-moment correlation technique were implemented to determine the strength and direction of the relationship between the reading and science achievements of the study group. To test the first research hypothesis, a Pearson product-correlation technique was used to estimate the relationship between English reading achievement and the English science achievement of the study group. The obtained correlation coefficient of r = + .51 was statistically significant ( p Pearson product-moment correlation technique was used to estimate the relationship between the Spanish reading achievement and the Spanish science achievement of the study group. The obtained correlation coefficient of r = + .53 was statistically significant (p < .001). This also is viewed as a moderate to strong relationship. The results of this study suggest that science achievement, as measured by the TAKS tests, is influenced by a student's reading achievement and may not be a valid assessment of their science knowledge but a combination of both their reading and science ability. These results also suggest that to improve the validity of the science TAKS test, it should be modified to include more authentic assessment measures which do not rely so much on reading ability.

  15. Extremely Low Density InAs Quantum Dots with No Wetting Layer

    Institute of Scientific and Technical Information of China (English)

    HUANG She-Song; NIU Zhi-Chuan; NI Hai-Qiao; ZHAN Feng; ZHAO Huan; SUN Zheng; XIA Jian-Bai

    2007-01-01

    Extremely low density inAs quantum dots (QDs) are grown by molecular beam droplet epitaxy.The gallium deposition amount is optimized to saturate exactly the excess arsenic atoms present on the GaAs substrate surface during growth,and low density InAs/GaAs QDs(4×106cm-2)are formed by depositing 0.65 monolayers(MLs)of indium.This is much less than the critical deposition thickness (1.7ML),which is necessary to form InAs/GaAs QDs with the conventional Stranski-Krastanov growth mode.The narrow photoluminescence linewidth of about 24 meV is insensitive to cryostat temperatures from 10 K to 250 K.All measurements indicate that there is no wetting layer connecting the QDs.

  16. The postgraduate hospital educational environment measure (PHEEM questionnaire identifies quality of instruction as a key factor predicting academic achievement

    Directory of Open Access Journals (Sweden)

    Joaquim Edson Vieira

    2008-01-01

    Full Text Available OBJECTIVE: This study analyzes the reliability of the PHEEM questionnaire translated into Portuguese. We present the results of PHEEM following distribution to doctors in three different medical residency programs at a university hospital in Brazil. INTRODUCTION: Efforts to understand environmental factors that foster effective learning resulted in the development of a questionnaire to measure medical residents' perceptions of the level of autonomy, teaching quality and social support in their programs. METHODS: The questionnaire was translated using the modified Brislin back-translation technique. Cronbach's alpha test was used to ensure good reliability and ANOVA was used to compare PHEEM results among residents from the Surgery, Anesthesiology and Internal Medicine departments. The Kappa coefficient was used as a measure of agreement, and factor analysis was employed to evaluate the construct strength of the three domains suggested by the original PHEEM questionnaire. RESULTS: The PHEEM survey was completed by 306 medical residents and the resulting Cronbach's alpha was 0.899. The weighted Kappa was showed excellent reliability. Autonomy was rated most highly by Internal Medicine residents (63.7% ± 13.6%. Teaching was rated highest in Anesthesiology (66.7% ± 15.4%. Residents across the three areas had similar perceptions of social support (59.0% ± 13.3% for Surgery; 60.5% ± 13.6% for Internal Medicine; 61.4% ± 14.4% for Anesthesiology. Factor analysis suggested that nine factors explained 58.9% of the variance. CONCLUSIONS: This study indicates that PHEEM is a reliable instrument for measuring the quality of medical residency programs at a Brazilian teaching hospital. The results suggest that quality of teaching was the best indicator of overall response to the questionnaire.

  17. Interpretation of thermal conductivity in LaFeAsO at low temperatures

    International Nuclear Information System (INIS)

    Thermal conductivity κ(T) of LaFeAsO is theoretically investigated below the spin density wave (SDW) anomaly. The lattice contribution to the thermal conductivity (κph) is discussed within the Debye-type relaxation rate approximation in terms of the acoustic phonon frequency and relaxation time below 150 K. The theory is formulated when heat transfer is limited by the scattering of phonons from defects, grain boundaries, charge carriers, and phonons. The lattice thermal conductivity dominates in LaFeAsO and is an artifact of strong phonon-impurity and -phonon scattering mechanism. Our result indicates that the maximum contribution comes from phonon scatters and various thermal scattering mechanisms provide a reasonable explanation for maximum appeared in κ (T)

  18. Interpretation of thermal conductivity in LaFeAsO at low temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Lodhi, Pavitra Devi; Kaurav, Netram, E-mail: netramkaurav@yahoo.co.uk [Department of Physics, Govt. Holkar Science college, A. B. Road, Indore-452001 (India); Parchur, A. K. [Department of Biological Engineering, Utah State University, Logan, UT-84322 U.S.A (United States); Choudhary, K. K. [Department of Physics, National Defence Academy, Khadakwasla, Pune-411 0231 India (India)

    2015-06-24

    Thermal conductivity κ(T) of LaFeAsO is theoretically investigated below the spin density wave (SDW) anomaly. The lattice contribution to the thermal conductivity (κ{sub ph}) is discussed within the Debye-type relaxation rate approximation in terms of the acoustic phonon frequency and relaxation time below 150 K. The theory is formulated when heat transfer is limited by the scattering of phonons from defects, grain boundaries, charge carriers, and phonons. The lattice thermal conductivity dominates in LaFeAsO and is an artifact of strong phonon-impurity and -phonon scattering mechanism. Our result indicates that the maximum contribution comes from phonon scatters and various thermal scattering mechanisms provide a reasonable explanation for maximum appeared in κ (T)

  19. Low-cost copper complexes as p-dopants in solution processable hole transport layers

    International Nuclear Information System (INIS)

    We demonstrate the usage of the Lewis-acidic copper(II)hexafluoroacetylacetonate (Cu(hfac)2) and copper(II)trifluoroacetylacetonate (Cu(tfac)2) as low-cost p-dopants for conductivity enhancement of solution processable hole transport layers based on small molecules in organic light emitting diodes (OLEDs). The materials were clearly soluble in mixtures of environmentally friendly anisole and xylene and spin-coated under ambient atmosphere. Enhancements of two and four orders of magnitude, reaching 4.0 × 10−11 S/cm with a dopant concentration of only 2 mol% Cu(hfac)2 and 1.5 × 10−9 S/cm with 5 mol% Cu(tfac)2 in 2,2′,7,7′-tetra(N,N-ditolyl)amino-9,9-spiro-bifluorene (spiro-TTB), respectively, were achieved. Red light emitting diodes were fabricated with reduced driving voltages and enhanced current and power efficiencies (8.6 lm/W with Cu(hfac)2 and 5.6 lm/W with Cu(tfac)2) compared to the OLED with undoped spiro-TTB (3.9 lm/W). The OLED with Cu(hfac)2 doped spiro-TTB showed an over 8 times improved LT50 lifetime of 70 h at a starting luminance of 5000 cd/m2. The LT50 lifetime of the reference OLED with PEDOT:PSS was only 8 h. Both non-optimized OLEDs were operated at similar driving voltage and power efficiency

  20. Low-cost copper complexes as p-dopants in solution processable hole transport layers

    Energy Technology Data Exchange (ETDEWEB)

    Kellermann, Renate [Department for Materials Science and Engineering, Chair for Materials for Electronics and Energy Technology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen 91058 (Germany); Siemens AG – Corporate Technology, Guenther-Scharowsky-Str. 1, Erlangen 91058 (Germany); Taroata, Dan; Maltenberger, Anna; Hartmann, David; Schmid, Guenter [Siemens AG – Corporate Technology, Guenther-Scharowsky-Str. 1, Erlangen 91058 (Germany); Brabec, Christoph J. [Department for Materials Science and Engineering, Chair for Materials for Electronics and Energy Technology, Friedrich-Alexander-University Erlangen-Nuremberg, Erlangen 91058 (Germany)

    2015-09-07

    We demonstrate the usage of the Lewis-acidic copper(II)hexafluoroacetylacetonate (Cu(hfac){sub 2}) and copper(II)trifluoroacetylacetonate (Cu(tfac){sub 2}) as low-cost p-dopants for conductivity enhancement of solution processable hole transport layers based on small molecules in organic light emitting diodes (OLEDs). The materials were clearly soluble in mixtures of environmentally friendly anisole and xylene and spin-coated under ambient atmosphere. Enhancements of two and four orders of magnitude, reaching 4.0 × 10{sup −11} S/cm with a dopant concentration of only 2 mol% Cu(hfac){sub 2} and 1.5 × 10{sup −9} S/cm with 5 mol% Cu(tfac){sub 2} in 2,2′,7,7′-tetra(N,N-ditolyl)amino-9,9-spiro-bifluorene (spiro-TTB), respectively, were achieved. Red light emitting diodes were fabricated with reduced driving voltages and enhanced current and power efficiencies (8.6 lm/W with Cu(hfac){sub 2} and 5.6 lm/W with Cu(tfac){sub 2}) compared to the OLED with undoped spiro-TTB (3.9 lm/W). The OLED with Cu(hfac){sub 2} doped spiro-TTB showed an over 8 times improved LT{sub 50} lifetime of 70 h at a starting luminance of 5000 cd/m{sup 2}. The LT{sub 50} lifetime of the reference OLED with PEDOT:PSS was only 8 h. Both non-optimized OLEDs were operated at similar driving voltage and power efficiency.

  1. New ultra low permittivity composites for use in ceramic packaging of Ga:As integrated circuits

    Science.gov (United States)

    Cross, L. E.

    1985-09-01

    This report documents work performed to develop materials systems for use in the ceramic packaging of Ga:As integrated circuits. Topics under study at Penn State are: dielectrics produced from Macro-Defect-Free (MDF) cements. Both aluminate and silicate based cements have been studied. The objectives of the first year's work have been to show that suitable test tablets can be produced which exhibit dielectric losses less than 1% into the frequency range of 2.5 GHz. Current work is focused upon lowering the permittivity level using silica microballoons dispersed in the matrix. Sol-gel preparation of both thick (25 microns) and thin (0.5 microns) SiO2 and silica:alumina films has shown that in the diphasis system, it is possible to produce crack-free monoliths with permittivities in the range 1.6 to 2.0 and loss tangents below .003. In the thin films, capping of columnar sputtered etched films has been demonstrated. For etched Schott and Vycor glass structures, permittivities in the range 2.5 to 3.0 have been measured with excellent low loss properties. Sputtered silicon films have been sucessfully etched to yield highly planar columnar structures up to 25 microns meters thick. Experiments are in progress to convert the silicon to SiO2 by an oxidation step and capping of the columnar structure using sol-gel coatings has been achieved. In a parallel program at Interamics, new families of borosilicate glass bonded alumina ceramics are being developed.

  2. High intensity low temperature (HILT) performance of space concentrator GaInP/GaInAs/Ge MJ SCs

    International Nuclear Information System (INIS)

    In the work, the results of an investigation of GaInP/GaInAs/Ge MJ SCs intended for converting concentrated solar radiation, when operating at low temperatures (down to −190 °C) are presented. A kink of the cell I-V characteristic has been observed in the region close to Voc starting from −20°C at operation under concentrated sunlight. The causes for its occurrence have been analyzed and the reasons for formation of a built-in potential barrier for majority charge carriers at the n-GaInP/n-Ge isotype hetero-interface are discussed. The effect of charge carrier transport in n-GaInP/n-pGe heterostructures on MJ SC output characteristics at low temperatures has been studied including EL technique

  3. High intensity low temperature (HILT) performance of space concentrator GaInP/GaInAs/Ge MJ SCs

    Energy Technology Data Exchange (ETDEWEB)

    Shvarts, Maxim Z., E-mail: shvarts@scell.ioffe.ru; Kalyuzhnyy, Nikolay A.; Mintairov, Sergey A.; Soluyanov, Andrei A.; Timoshina, Nailya Kh. [Ioffe Physical-Technical Institute, 26 Polytekhnicheskaya str., St.-Petersburg, 194021 (Russian Federation); Gudovskikh, Alexander S. [Saint-Petersburg Academic University - Nanotechnology Research and Education Centre RAS, St. Petersburg, 194021 (Russian Federation); Luque, Antonio [Ioffe Physical-Technical Institute, 26 Polytekhnicheskaya str., St.-Petersburg, 194021, Russia and Instituto de Energia Solar, Universidad Politecnica de Madrid, Madrid (Spain)

    2014-09-26

    In the work, the results of an investigation of GaInP/GaInAs/Ge MJ SCs intended for converting concentrated solar radiation, when operating at low temperatures (down to −190 °C) are presented. A kink of the cell I-V characteristic has been observed in the region close to V{sub oc} starting from −20°C at operation under concentrated sunlight. The causes for its occurrence have been analyzed and the reasons for formation of a built-in potential barrier for majority charge carriers at the n-GaInP/n-Ge isotype hetero-interface are discussed. The effect of charge carrier transport in n-GaInP/n-pGe heterostructures on MJ SC output characteristics at low temperatures has been studied including EL technique.

  4. GaAs Wideband Low Noise Amplifier Design for Breast Cancer Detection System

    DEFF Research Database (Denmark)

    Yan, Lei; Krozer, Viktor; Delcourt, Sebastien; Zhurbenko, Vitaliy; Johansen, Tom Keinicke; Jiang, Chenhui

    2009-01-01

    Modern wideband systems require low-noise receivers with bandwidth approaching 10 GHz. This paper presents ultra-wideband stable low-noise amplifier MMIC with cascode and source follower buffer configuration using GaAs technology. Source degeneration, gate and shunt peaking inductors are used to ...... good agreement with simulated values. It is discussed in the paper that with more inductive peaking amplifier operation can be extended to even higher frequency, resulting in an even larger bandwidth....

  5. Clinical examination findings as prognostic factors in low back pain: a systematic review of the literature

    OpenAIRE

    Hartvigsen, Lisbeth; Kongsted, Alice; Hestbaek, Lise

    2015-01-01

    Background There is a strong tradition of performing a clinical examination of low back pain (LBP) patients and this is generally recommended in guidelines. However, establishing a pathoanatomic diagnosis does not seem possible in most LBP patients and clinical tests may potentially be more relevant as prognostic factors. The aim of this review of the literature was to systematically assess the association between low-tech clinical tests commonly used in adult patients with acute, recurrent o...

  6. Carrier lifetime under low and high electric field conditions in semi-insulating GaAs

    International Nuclear Information System (INIS)

    The mobility lifetime product of holes and electrons under low electric field conditions was determined by alpha spectroscopy using SI-GaAs as a photo conductivity detector. The lifetime in high electric field (≥104 V/cm) of electrons was investigated with Schottky diodes. Both results were analyzed as a function of substrate resistivity and trap concentrations. We identified the ionized arsenic antisite defect (EL2+) as the dominant electron trap in the high field region and determined the capture cross-section as being (8.0±0.6) x 10-14 cm2. (orig.)

  7. Cryogenic Current Comparator as Low Intensity Beam Current Monitor in the CERN Antiproton Decelerators

    CERN Document Server

    Fernandes, M; Soby, L; Welsch, CP

    2013-01-01

    In the low-energy Antiproton Decelerator (AD) and the future Extra Low ENergy Antiproton (ELENA) rings at CERN, an absolute measurement of the beam intensity is essential to monitor any losses during the deceleration and cooling phases. However, existing DC current transformers can hardly reach the μA level, while at the AD and ELENA currents can be as low as 100 nA. A Cryogenic Current Comparator (CCC) based on a superconducting quantum interference device (SQUID) is currently being designed and shall be installed in the AD and ELENA machines. It should meet the following specifications: A current resolution smaller than 10 nA, a dynamic range covering currents between 100 nA and 1 mA, as well as a bandwidth from DC to 1 kHz. Different design options are being considered, including the use of low or high temperature superconductor materials, different CCC shapes and dimensions, different SQUID characteristics, as well as electromagnetic shielding requirements. In this contribution we present first results f...

  8. Could Elementary Textbooks Serve as Models of Practice to Help New Teachers and Non-Specialists Attend to Reasoning in Music?

    Science.gov (United States)

    Newton, Douglas P.; Newton, Lynn D.

    2006-01-01

    For good reason, many believe that class teachers should make a significant contribution to the music education of young children. In practice, these teachers are often unenthusiastic about the task, feeling that they lack the knowledge and skills to teach music with confidence. Could elementary music textbooks intended for children serve as…

  9. Multichannel Recorder for Low Frequency Signals: Application of Oscilloscope as Integrated Mobile Service for a Smartphone

    Directory of Open Access Journals (Sweden)

    Michal Kochlan

    2016-01-01

    Full Text Available Data acquisition and processing are well known for some time. Many applications use powerful hardware to acquire, process, and visualize signal waveforms. But there are some applications that do not have to perform high resolution signal acquisition and process large amount of data, for example, low frequency applications of embedded design and applications for remote power grid monitoring. The paper describes special system for low frequency signal data sample acquisition, processing, and visualization implemented as a service on Android-based smart device. The service makes smart device functioning as an oscilloscope or arbitrary waveform generator which is accessible remotely through Bluetooth. The design respects low power consumption requirements, simplicity, and user friendliness in application design. Application scenario was implemented as wireless data acquisition system for power grid monitoring.

  10. Low voltage copper phthalocyanine organic thin film transistors with a polymer layer as the gate insulator

    International Nuclear Information System (INIS)

    Low voltage organic thin film transistors (OTFTs) were created using polymethyl-methacrylate-co g-lyciclyl-methacrylate (PMMA-GMA) as the gate dielectric. The OTFTs performed acceptably at supply voltages of about 10 V. From a densely packed copolymer brush, a leakage current as low as 2 x 10-8 A/cm2 was obtained. From the measured capacitance-insulator frequency characteristics, a dielectric constant in the range 3.9-5.0 was obtained. By controlling the thickness of the gate dielectric, the threshold voltage was reduced from -3.5 to -2.0 V. The copper phthalocyanine (CuPc) based organic thin film transistor could be operated at low voltage and 1.2 x 10-3 cm2/(V·s) mobility. (semiconductor devices)

  11. Utilization of peatlands as possible land resource for low-input agriculture: cultivation of Vaccinium species as an example

    Science.gov (United States)

    Tonutare, Tonu; Rodima, Ako; Rannik, Kaire; Shanskiy, Merrit

    2013-04-01

    The best way of soil protection is its sustainable and expedient use, which secures soils ecological functioning. Recent years, by exploitation of peat soils for their different use, has raised important issues concerning their input to global climate change as important source of greenhouse gases (GHG) emitters. The dynamics of GHG are determined by different factors as: site specific conditions including hydrology, soil type, vegetation, area management, including meteorological and climatic conditions. Therefore, in this current paper we are presenting the study results were we estimated CO2, CH4 and N2O emissions from exhausted cultivated peatland with Vaccinium species and determined the soil chemical composition. For comparision a virgin state peatland was observed. The main goals of the paper are: (1) to present the experimental results of greenhouse gases generation and peat chemical composition (antioxidant activity of peat, C/N ratio, fiber content, water extractable phenolics) relationships on different microsites either on natural plant cover or Vaccinium species cultivation area on exhausted milled peat area; (2) to discuss how peat soil quality contributes to greenhouse gases emission; (3) and what kind of relationship reveals between low input agricultural system in which Vaccinium species are cultivated on exhausted milled peat area. The study are is located in nearby Ilmatsalu (58°23'N, 26°31'E) in South Estonia, inside of which the three microsites are determined. Microsites are different from each other by exploitation and plant cover type. 1). Natural plant cover, 2). Cultivated area with Vaccinium angustifolium x V. corymbosum, 3). Cultivated area with Vaccinium angustifolium. The determined soil type according to WRB was Fibri Dystric Histosol. The main part of study focuses on the analyses of greenhouse gases. For this purpose the closed chamber method was used. The greenhouse gas samples were collected from spring to autumn 2011 throughout

  12. Development of a piston utilizing carbon-cluster as a pressure transmission medium at low temperature

    International Nuclear Information System (INIS)

    It is necessary to require pressure transmission mechanism in the vacuum and low temperature environment such mechanically RF tuning operation for superconducting RF cavities. As a medium of pressure transmission, water, oil and air can not use such environment. Nano-cluster particles and carbon seems to have possibility of pressure transmission medium. Because their characteristics of chemical and physical reaction at low temperature environment is very stable. Also they have small number of the friction coefficient. We have been studying possibility of their characteristics as pressure transmission medium. (author)

  13. Exercise as a mean to control low-grade systemic inflammation

    DEFF Research Database (Denmark)

    Mathur, Neha; Pedersen, Bente Klarlund

    2008-01-01

    Chronic noncommunicable diseases (CNCDs), which include cardiovascular disease, some cancers, for example, colon cancer, breast cancer, and type 2 diabetes, are reaching epidemic proportions worldwide. It has now become clear that low-grade chronic inflammation is a key player in the pathogenesis...... introduced as the first myokine, defined as a cytokine, which is produced and released by contracting skeletal muscle fibres, exerting its effects in other organs of the body. We suggest that skeletal muscle is an endocrine organ and that myokines may be involved in mediating the beneficial effects against...... CNCDs associated with low-grade inflammation....

  14. Low-dose radiotherapy as treatment for benign lymphoepitelial lesion in HIV-patients

    International Nuclear Information System (INIS)

    Standard treatments for benign lymphoepitelial lesion of the parotid gland in patients infected with the human immunodeficiency virus (HIV) are unsatisfactory. Recently, low-dose radiotherapy has been proposed as a noninvasive treatment option. We describe a case of bilateral benign lymphoepitelial lesion parotid gland in a HIV-positive paint, treated by radiotherapy. Low-dose radiotherapy, appears as a alternative in the treatment for benign lymphoepitelial lesion in HIV-patients, and preliminary evaluations have indicated that this treatment is effective from both the clinical and cosmetic points of view

  15. Risks of low-LET radiation as given in BEIR-III and previous reports

    International Nuclear Information System (INIS)

    This report presents the conclusions of a review of the report ΣThe Effects on Populations of Exposure to Low Levels of Ionizing RadiationΣ, BEIR-III, published by the U.S. National Academy of Sciences in 1980 and other related reports. The committee concludes that, in as far as the estimates of risk from low-LET radiation are concerned, the BEIR-III report does not provide any new data that might suggest that the present dose limits promulgated by the AECB should be changed

  16. Microbial respiration and gene expression as a function of very low oxygen concentration

    DEFF Research Database (Denmark)

    Tiano, Laura

    with other methods suitable for measurements at low O2 (Manuscript IV) showing comparable results, together with an overall higher precision and less susceptibility to bias from light/temperature effects. The resolution of the measurements with the STOX sensor is inversely proportional to the O2...... vanishingly low O2 concentrations, and they are likely to co-occur, in some environments, with anaerobic ones. These findings call for a need to change and reshape our definitions of oxic and anoxic environments, as well as the microbial metabolic pathways involved; thus to expand our knowledge on this topic...

  17. Studies on electrical double layer capacitor with a low-viscosity ionic liquid 1-ethyl-3-methylimidazolium tetracyanoborate as electrolyte

    Indian Academy of Sciences (India)

    G P Pandey; S A Hashmi

    2013-08-01

    The performance of an electrical double layer capacitor (EDLC) composed of high surface area activated carbon electrodes and a new ionic liquid, 1-ethyl-3-methylimidazolium tetracyanoborate, [EMIm]TCB, as the electrolyte has been investigated by impedance spectroscopy, cyclic voltammetry and galvanostatic charge–discharge studies. The high ionic conductivity (∼1.3 × 10-2 S cm-1 at 20 °C) and low viscosity (∼22 cP) of the ionic liquid, [EMIm]TCB, make it attractive as electrolyte for its use in EDLCs. The optimum capacitance value of 195.5 F g-1 of activated carbon has been achieved with stable cyclic performance.

  18. Measured attention in prolonged over-learned response tasks and its correlation to high level scientific reasoning and school achievement

    OpenAIRE

    R. Hotulainen; H. Thuneberg; J. Hautamäki; M.-P. Vainikainen

    2014-01-01

    The relationship between attention and academic performance has been of interest starting with early studies on academic success and failure. In this study we examine how attention measured in simple and prolonged over-learned response tasks correlates with and contributes to scientific reasoning and school achievement (GPA). To study attention, the Attention Concentration Test (ACT) was used and to study scientific reasoning, a modified version of Science Reasoning Tasks, tapping control-of-...

  19. Scientific Reasoning, School Achievement and Gender: A Multilevel Study of between and within School Effects in Finland

    Science.gov (United States)

    Thuneberg, Helena; Hautamäki, Jarkko; Hotulainen, Risto

    2015-01-01

    The relationships between reasoning and school achievement were studied taking into account the multilevel nature (school- and class-levels) of the data. We gathered data from 51 classes at seven schools in metropolitan and Eastern Finland (N = 769, 395 males, 15-year-old students). To study scientific reasoning, we used a modified version of…

  20. Low temperature processed planar heterojunction perovskite solar cells employing silver nanowires as top electrode

    Science.gov (United States)

    Zhang, Jianhua; Li, Fushan; Yang, Kaiyu; Veeramalai, Chandrasekar Perumal; Guo, Tailiang

    2016-04-01

    In this paper, we reported a low temperature processed planar heterojunction perovskite solar cell employing silver nanowires as the top electrode and ZnO nanoparticles as the electron transport layer. The CH3NH3PbI3 perovskite was grown as the light absorber via two-step spin-coating technique. The as-fabricated perovskite solar cell exhibited the highest power conversion efficiency of 9.21% with short circuit current density of 19.75 mA cm-2, open circuit voltage of 1.02, and fill factor value of 0.457. The solar cell's performance showed negligible difference between the forward and reverse bias scan. This work paves a way for realizing low cost solution processable solar cells.

  1. Choked Jets and Low-Luminosity Gamma-Ray Bursts as Hidden Neutrino Sources

    CERN Document Server

    Senno, Nicholas; Meszaros, Peter

    2015-01-01

    We consider choked gamma-ray burst (GRB) jets as possible sources of high-energy cosmic neutrinos. We take into account the jet propagation physics and radiation constraints, which are relevant for high-energy neutrino production in dense environments. Efficient shock acceleration of cosmic rays inside a high density stellar environment is possible for sufficiently low-power jets and/or jets buried in an extended envelope, and such conditions are favorable also for the GRB jets to become stalled. Such choked jets may explain transrelativistic SNe and low-luminosity (LL) GRBs. Focusing on this possibility, we calculate the resulting neutrino spectra including the relevant microphysical processes such as multipion production in pp and pgamma interactions, as well as the energy losses of mesons and muons. We obtain diffuse neutrino spectra using the latest results on the luminosity function of LL GRBs. Although current uncertainties are large, we confirm that LL GRBs can potentially give a significant contributi...

  2. Low Bandgap InAs-Based Thermophotovoltaic Cells for Heat-Electricity Conversion

    Science.gov (United States)

    Krier, A.; Yin, M.; Marshall, A. R. J.; Krier, S. E.

    2016-06-01

    The practical realization of thermophotovoltaic (TPV) cells, which can directly convert heat into electric power, is of considerable technological interest. However, most existing TPV cells require heat sources at temperatures of ˜1800°C. Here we report a low bandgap mid-infrared cell based on InAs and demonstrate TPV operation with heat sources at temperatures in the range 500-950°C. The maximum open circuit voltage ( V oc) and short circuit current density ( J sc) were measured as 0.06 V and 0.89 A cm-2 for a blackbody temperature of 950°C and an incident power density of 720 mW cm-2 without antireflection coating or electrode optimisation. TPV operation was obtained with heat sources at temperatures as low as 500°C, which represents progress towards energy scavenging and waste heat recovery applications.

  3. Suppression of low-frequency charge noise in gates-defined GaAs quantum dots

    Energy Technology Data Exchange (ETDEWEB)

    You, Jie; Li, Hai-Ou, E-mail: haiouli@ustc.edu.cn, E-mail: gpguo@ustc.edu.cn; Wang, Ke; Cao, Gang; Song, Xiang-Xiang; Xiao, Ming; Guo, Guo-Ping, E-mail: haiouli@ustc.edu.cn, E-mail: gpguo@ustc.edu.cn [Key Laboratory of Quantum Information, Chinese Academy of Sciences, University of Science and Technology of China, Hefei, Anhui 230026 (China); Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China)

    2015-12-07

    To reduce the charge noise of a modulation-doped GaAs/AlGaAs quantum dot, we have fabricated shallow-etched GaAs/AlGaAs quantum dots using the wet-etching method to study the effects of two-dimensional electron gas (2DEG) underneath the metallic gates. The low-frequency 1/f noise in the Coulomb blockade region of the shallow-etched quantum dot is compared with a non-etched quantum dot on the same wafer. The average values of the gate noise are approximately 0.5 μeV in the shallow-etched quantum dot and 3 μeV in the regular quantum dot. Our results show the quantum dot low-frequency charge noise can be suppressed by the removal of the 2DEG underneath the metallic gates, which provides an architecture for noise reduction.

  4. Suppression of low-frequency charge noise in gates-defined GaAs quantum dots

    International Nuclear Information System (INIS)

    To reduce the charge noise of a modulation-doped GaAs/AlGaAs quantum dot, we have fabricated shallow-etched GaAs/AlGaAs quantum dots using the wet-etching method to study the effects of two-dimensional electron gas (2DEG) underneath the metallic gates. The low-frequency 1/f noise in the Coulomb blockade region of the shallow-etched quantum dot is compared with a non-etched quantum dot on the same wafer. The average values of the gate noise are approximately 0.5 μeV in the shallow-etched quantum dot and 3 μeV in the regular quantum dot. Our results show the quantum dot low-frequency charge noise can be suppressed by the removal of the 2DEG underneath the metallic gates, which provides an architecture for noise reduction

  5. Low band gap polymeric solar cells using solution-processable copper iodide as hole transporting layer

    Science.gov (United States)

    Chaudhary, Neeraj; Kesari, J. P.; Chaudhary, Rajiv; Patra, Asit

    2016-08-01

    In the present work, we have shown the performance of solution-processable copper iodide (CuI) as an alternative hole transporting layer (HTL) for polymeric solar cells. Optical spectra of the CuI thin film reveal highly transparent and practically no absorption in the range vis-NIR region (450-1110 nm). X-ray diffraction (XRD) patterns of CuI exhibits as a p-type semiconductor as well as crystalline nature. The photovoltaic devices were fabricated using PCDTBT and PTB7 as donor materials blended with PC71BM as an acceptor material. The power conversion efficiencies (PCEs) based on CuI as an HTL have been achieved to up to 3.04% and 4.48% for PCDTBT and PTB7 based donor materials respectively with a configuration based on ITO/CuI(40 nm)/active layer (60 nm)/Al (120 nm). This study clearly indicated that the devices made with CuI as an HTL showed superior performance than the device fabricated from PEDOT:PSS layer as an HTL. Morphological characterization of the HTL using scanning electron microscopy (SEM) and atomic force microscope (AFM) were carried for better understanding.

  6. TRPV Channels in Mast Cells as a Target for Low-Level-Laser Therapy

    OpenAIRE

    Lina Wang; Di Zhang; Wolfgang Schwarz

    2014-01-01

    Low-level laser irradiation in the visible as well as infrared range is applied to skin for treatment of various diseases. Here we summarize and discuss effects of laser irradiation on mast cells that leads to degranulation of the cells. This process may contribute to initial steps in the final medical effects. We suggest that activation of TRPV channels in the mast cells forms a basis for the underlying mechanisms and that released ATP and histamine may be putative mediators for therapeutic ...

  7. Analysis of low-level interaction events as a proxy for familiarity

    OpenAIRE

    Apaolaza, Aitor

    2016-01-01

    This thesis provides insight into long-term factors of user behaviour with a Web site or application using low-level interaction events (such as mouse movement, and scroll action) as a proxy. Current laboratory studies employ scenarios where confounding variables can be controlled. Unfortunately, these scenarios are not naturalistic or ecologically valid. Existing remote alternatives fail to provide either the required granularity or the necessary naturalistic aspect. Without appropriate long...

  8. Virtual screening of low molecular weight mushrooms compounds as potential Mdm2 inhibitors.

    OpenAIRE

    Froufe, Hugo J. C.; Abreu, Rui M. V.; Ferreira, Isabel C. F. R.

    2012-01-01

    In some human cancer cases, the activity of p53 is inhibited by overexpressed Mdm2. Mdm2 acts as an ubiquitin ligase, resulting in p53 ubiquitination and subsequent p53 proteasomal degradation. The disruption of the Mdm2-p53 interaction using small-molecule inhibitors is recognized as a promising strategy for anticancer drug design. Mushrooms are an important source of powerful compounds with antitumor properties. In this study, we present the first virtual screening of low molecular weight c...

  9. FLUOROETHERS AS A WORKING FLUIDS FOR LOW TEMPERATURE ORGANIC RANKINE CYCLE

    OpenAIRE

    Artemenko S.V

    2014-01-01

    Hydrofluoroethers as a new class of working fluids for the organic Rankine cycle have been considered to utilize the low-potential waste heat. Temperature range 300…400 K was chosen to provide energy conversion of waste heat from fuel cells. The direct assessment of the efficiency criteria for the Rankine cycle via artificial neural networks (ANN) was used. To create ANN the critical parameters of substance and normal boiling temperature as input were chosen. The forecast of efficiency criter...

  10. Yoga as a treatment for chronic low back pain: A systematic review of the literature

    OpenAIRE

    Chang, Douglas G.; Holt, Jacquelyn A.; Sklar, Marisa; Groessl, Erik J.

    2016-01-01

    Objectives Chronic low back pain (CLBP) affects millions of people worldwide, and appears to be increasing in prevalence. It is associated not only with pain, but also with increased disability, psychological symptoms, and reduced quality of life. There are various treatment options for CLBP, but no single therapy stands out as being the most effective. In the past 10 years, yoga interventions have been studied as a CLBP treatment approach. The objective of this paper is to review the current...

  11. MOSFET with a boron-loaded gate as a low-energy neutron dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Gavelle, M. [CNRS, LAAS, 7 avenue du colonel Roche, F-31077 Toulouse Cedex 4 (France); Universite de Toulouse, UPS, INSA, INP, ISAE, LAAS, F-31077 Toulouse (France); Sarrabayrouse, G., E-mail: sarra@laas.fr [CNRS, LAAS, 7 avenue du colonel Roche, F-31077 Toulouse Cedex 4 (France); Universite de Toulouse, UPS, INSA, INP, ISAE, LAAS, F-31077 Toulouse (France); Scheid, E. [CNRS, LAAS, 7 avenue du colonel Roche, F-31077 Toulouse Cedex 4 (France); Universite de Toulouse, UPS, INSA, INP, ISAE, LAAS, F-31077 Toulouse (France); Siskos, S.; Fragopoulou, M.; Zamani, M. [Aristotle University of Thessaloniki, Physics Department, 54124 Thessaloniki (Greece)

    2011-12-15

    A MOSFET-based low-energy neutron dosimeter has been fabricated using a {sup 10}B loaded gate electrode as (n,{alpha}) converter. The response to thermal neutrons has been studied. - Highlights: > Feasibility of a metal-oxide-semiconductor thermal neutron dosimeter is investigated. > Monolithically integrated boron-loaded gate electrode acts as a (n,{alpha}) converter. > Sensitivity of 2 V/Sv is obtained.

  12. Low-cost hydrophobic layer as a top plate in two-plate digital microfluidics

    Science.gov (United States)

    Tabatabaeipour, Ghiasadin; Hajghassem, Hassan; MohtashamiFar, Mansoor

    2015-07-01

    Digital microfluidics is an emerging technology that is able to manipulate droplets individually. To develop this technology it is needed to use cheaper and more accessible materials for its fabrication. At present, materials commonly used for the hydrophobic layer in these devices are expensive materials that require a legal agreement. In this paper, polydimethylsiloxane (PDMS), which is a common and cheap material in the field of microfluidic, is used as a hydrophobic material for both top and bottom plates of digital microfluidic devices. The droplet cannot be actuated using DC voltage in a surrounding air environment. The reason for the droplet pinning is the high contact angle hysteresis of PDMS surface and considerable thickness of hydrophobic layer on the top plate. In order to overcome this problem, we have exploited a suitable AC voltage (230 Vrms and 8 kHz) as well as changing the surrounding environment to the olive oil. Therefore this paper demonstrates the feasibility of using PDMS as a hydrophobic layer in two-plate digital microfluidics.

  13. Relative Effectiveness of Two Approaches to the Teaching of Music Theory on the Achievement and Attitudes of Undergraduate Students Training as Church Musicians

    Science.gov (United States)

    Kinchen, John Dawson, III

    2012-01-01

    As a result of a perceived need to improve the music theory curricula for the preparation of church music leaders, this study compared two diverse approaches to the teaching of music theory for church music university students on achievement, attitudes, and self-preparedness. This current study was a quantitative, quasi-experimental research…

  14. Effects of Using History as a Tool to Teach Mathematics on Students' Attitudes, Anxiety, Motivation and Achievement in Grade 11 Classrooms

    Science.gov (United States)

    Lim, Siew Yee; Chapman, Elaine

    2015-01-01

    For decades, educators have advocated using history of mathematics in mathematics classrooms. Empirical research on the efficacy of this practice, however, is scarce. A quasi-experiment was used to investigate the effects of using history as a tool to teach mathematics on grade 11 students' mathematics achievement. Effects in three affective…

  15. Social and Musical Objectives or Experiences School Music Teachers Anticipate Their Students Will Achieve as a Result of Attending a Summer Music Camp

    Science.gov (United States)

    Richards, Eric W.

    2011-01-01

    The purpose of this study was to investigate specific social and musical objectives or experiences school music teachers anticipate their students will achieve as a result of attending a summer music camp. A survey instrument was developed to collect demographic data and responses to questions regarding 14 specific musical and social variables.…

  16. Renewable and low-carbon energies as mitigation options of climate change for China

    NARCIS (Netherlands)

    Urban, F.; Benders, R. M. J.; Moll, H. C.

    2009-01-01

    This article discusses how renewable and low-carbon energies can serve as mitigation options of climate change in China's power sector. Our study is based on scenarios developed in PowerPlan, a bottom-up model simulating a countries' power sector and its emissions. We first adjusted the model to Chi

  17. Low temperature transport in p-doped InAs nanowires

    DEFF Research Database (Denmark)

    Upadhyay, Shivendra; Jespersen, Thomas Sand; Madsen, Morten Hannibal;

    2013-01-01

    We present low temperature electrical measurements of p-type Indium Arsenide nanowires grown via molecular beam epitaxy using Beryllium as a dopant. Growth of p-type wires without stacking faults is demonstrated. Devices in field-effect geometries exhibit ambipolar behavior, and the temperature...

  18. Low permeability Neogene lithofacies in Northern Croatia as potential unconventional hydrocarbon reservoirs

    Science.gov (United States)

    Malvić, Tomislav; Sučić, Antonija; Cvetković, Marko; Resanović, Filip; Velić, Josipa

    2014-06-01

    We present two examples of describing low permeability Neogene clastic lithofacies to outline unconventional hydrocarbon lithofacies. Both examples were selected from the Drava Depression, the largest macrostructure of the Pannonian Basin System located in Croatia. The first example is the Beničanci Field, the largest Croatian hydrocarbon reservoir discovered in Badenian coarse-grained clastics that consists mostly of breccia. The definition of low permeability lithofacies is related to the margins of the existing reservoir, where the reservoir lithology changed into a transitional one, which is mainly depicted by the marlitic sandstones. However, calculation of the POS (probability of success of new hydrocarbons) shows critical geological categories where probabilities are lower than those in the viable reservoir with proven reserves. Potential new hydrocarbon volumes are located in the structural margins, along the oil-water contact, with a POS of 9.375%. These potential reserves in those areas can be classified as probable. A second example was the Cremušina Structure, where a hydrocarbon reservoir was not proven, but where the entire structure has been transferred onto regional migration pathways. The Lower Pontian lithology is described from well logs as fine-grained sandstones with large sections of silty or marly clastics. As a result, the average porosity is low for conventional reservoir classification (10.57%). However, it is still an interesting case for consideration as a potentially unconventional reservoir, such as the "tight" sandstones.

  19. Low Cost Al-Si Casting Alloy As In-Situ Composite for High Temperature Applications

    Science.gov (United States)

    Lee, Jonathan A.

    2000-01-01

    A new aluminum-silicon (Al-Si) alloy has been successfully developed at NASA- Marshall Space Flight Center (MSFC) that has significant improvement in tensile and fatigue strength at elevated temperatures (500 F-700 F). The alloy offers a number of benefits such as light weight, high hardness, low thermal expansion and high surface wear resistance. In hypereutectic form, this alloy is considered as an in-situ Al-Si composite with tensile strength of about 90% higher than the auto industry 390 alloy at 600 F. This composite is very economically produced by using either conventional permanent steel molds or die casting. The projected material cost is less than $0.90 per pound, and automotive components such as pistons can be cast for high production rate using conventional casting techniques with a low and fully accounted cost. Key Words: Metal matrix composites, In-situ composite, aluminum-silicon alloy, hypereutectic alloy, permanent mold casting, die casting.

  20. Conformations of 1-heptene secondary ozonide as studied by low temperature FT-IR spectroscopy

    Science.gov (United States)

    Bariseviciute, R.; Ceponkus, J.; Sablinskas, V.; Kimtys, L.

    2007-11-01

    Conformational diversity of the 1-heptene secondary ozonides (SOZ) in solid neat films as well as isolated in Ar or CO 2 matrices was studied by the means of FT-IR absorption spectroscopy. The ozonization reaction was performed at 77 K in the neat films of the reactants. The spectra of the ozonide were analyzed by combining the experimental data with the results of theoretical calculations performed at B3LYP 6-311++G (3df, 3pd) level. It was found that the samples of 1-heptene secondary ozonide exist as a mixture of three dominating conformers. The most stable conformer is the one with O-O half-chair configuration of the five membered ring, the aliphatic radical attached to the ring in equatorial position and the aliphatic chain being in gauche (∠OCCC ≈ -60°) position. The other two stable conformers are equatorial with aliphatic chain in anti (∠OCCC ≈ 180°) and gauche (∠OCCC ≈ 60°) positions. It was found from Van't Hoff plots that Δ H of the equatorial anti conformer is equal to 0.24 ± 0.03 kJ/mol. The experimental value of Δ H is in reasonable accordance to the calculated one - 0.5 kJ/mol.

  1. FLUOROETHERS AS A WORKING FLUIDS FOR LOW TEMPERATURE ORGANIC RANKINE CYCLE

    Directory of Open Access Journals (Sweden)

    Artemenko S.V

    2014-12-01

    Full Text Available Hydrofluoroethers as a new class of working fluids for the organic Rankine cycle have been considered to utilize the low-potential waste heat. Temperature range 300…400 K was chosen to provide energy conversion of waste heat from fuel cells. The direct assessment of the efficiency criteria for the Rankine cycle via artificial neural networks (ANN was used. To create ANN the critical parameters of substance and normal boiling temperature as input were chosen. The forecast of efficiency criteria for the Rankine cycle as output parameter which reproduces the coefficient of performance with high accuracy and without thermodynamic property calculations was presented.

  2. Bismuth ferrite as low-loss switchable material for plasmonic waveguide modulator

    DEFF Research Database (Denmark)

    Babicheva, Viktoriia; Zhukovsky, Sergei; Lavrinenko, Andrei

    2014-01-01

    We propose new designs of plasmonic modulators, which can beused for dynamic signal switching in photonic integrated circuits. We studyperformance of a plasmonic waveguide modulator with bismuth ferrite as atunable material. The bismuth ferrite core is sandwiched between metalplates (metal-insulator-metal...... modulation in both phase andamplitude control schemes. Due to high field confinement between themetal layers, existence of mode cut-offs for certain values of the corethickness, and near-zero material losses in bismuth ferrite, efficientmodulation performance is achieved. For the phase control scheme...

  3. Application of Low-Phosphorous Fertilizers on Tea Plantations as a Novel Best Management Practice

    Directory of Open Access Journals (Sweden)

    Chi-Feng Chen

    2014-10-01

    Full Text Available Taipei Feitsui Reservoir supplies drinking water to more than five million citizens in northern Taiwan. The Feitsui Reservoir Administration and Tea Research and Extension Station have implemented a new pollution control measure for the use of low-phosphorous (low-P fertilizers to prevent eutrophication. In this study, we compared the quality of the soil, effluent and tea from two test fields. Low-P fertilizer was applied to one of the fields, and regular phosphorous fertilizer (regular-P was applied to the other. The study period covered spring and winter seasons. The results showed that the investigated soil chemical properties were not influenced by either the low-P or regular-P fertilizers. The effluent quality was influenced by the precondition of the soil, which resulted in a larger average total phosphorous (TP concentration in the low-P field. However, there was a decreasing trend in P concentration that amounted to approximately half of the average TP concentration in the regular-P field. The growth characteristics and yields were not significantly different between the two fields, but the taste and aroma of the tea from the low-P field was rated as superior to that of the regular-P field.

  4. The effects of low level laser therapy (Ga- Al- As on myofascial pain dysfunction syndrome

    Directory of Open Access Journals (Sweden)

    Sahebjamei M

    2002-06-01

    Full Text Available Muscular pain is one of the most common causes for facial pain. Myofacial pain dysfunction"nsyndrome (MPDS is one of the most important disorders of facial area that affected patients suffer from"npain, tenderness of one or more masticatory muscles and limitation of movements. Lack of specific and"neffective therapeutic method, makes it necessary to find a treatment to decrease pain. Considering the"nanalgesic and anti- inflammatory effects of low-level laser, some investigators have recommended it for"nMPDS patient's treatment. In this study, the effects of low level laser (Ga-Al-As on MPDS patients"nreferred to dental faculty of Tehran University of Medical Sciences, were investigated. Twenty- two"nMPDS patents, with mean age 33.32 years, were treated for 4 weeks (12 visits. Clinical examinations"nwere performed in 6 stages. The results of this study showed that variables such as pain severity, cheek"npain, pain frequency and tenderness of masseter, temporal, internal and external pterygoid muscles, had a"nstatistically significant improvement at the end of treatment with low level laser (GA-A1-AS which"nlasted for three months, (follow- up period. Results of this study showed that, low-level laser therapy"nhas a sedative effect on the pain and tenderness of masticatory muscles in MPDS. Patients and having an"naccurate and regular program to complete treatment period, has an important role in MPDS"nimprovement.

  5. rganizational features as situational strength: engaging the low-conscientious employee

    Directory of Open Access Journals (Sweden)

    Milam, A.

    2015-07-01

    Full Text Available One of the most robust findings in work psychology is the role that conscientiousness plays in performance; more recently, research indicates that conscientious employees are also the most engaged in their work. The present study examines whether the organization has any role in this relation, and if it is possible for individuals who are low in conscientiousness to also feel high levels of engagement. One hundred forty-one full-time Romanian workers and their peers, representing a variety of industries, were surveyed, revealing that features of the organization can actually attenuate the relation between conscientiousness and engagement. Specifically, when employees perceive that the organization is relatively formalized (i.e., where following rules is important, and in organizations where there is a perception that effort is rewarded, conscientiousness is not as strongly associated with engagement. These organizational features represent situational strength, and when situations are strong, scripts and rules tend to predict behavior, rather than personality. As such, it may be possible for low-conscientiousness individuals to actually become more engaged through organizational change. For those who are low in conscientiousness, for example, a formal work environment likely provides structure and decreases ambiguity, which aids in lower conscientious employees becoming more engaged. Similarly, when it is perceived that the organization rewards effort, those who are low in conscientiousness receive this reinforcement, and likely benefit the most, as their levels of engagement tend to approach those who are higher in conscientiousness.

  6. Low Blood Lead Levels and educational achievement in 7-8 year old children in the Community of Madrid (Spain Bajos niveles de plomo en sangre y rendimiento escolar en niños de 7-8 años en la Comunidad de Madrid (España Baixos níveis de chumbo no sangue e sucesso escolar nas crianças entre os 7-8 anos na Comunidade de Madrid (Espanha

    Directory of Open Access Journals (Sweden)

    María José Martínez García

    2013-06-01

    Full Text Available Background: Lead affects the behavioral and cognitive functions of children. The current lead safety level for avoiding these adverse effects is still controversial.Methods of study: A cross-sectional study included 511 children from 23 primary schools within the Comunidad de Madrid (the Madrid Region –including the city of Madrid and the large urban-industrial conurbation of satellite towns surrounding it, Spain. The children’s blood lead levels were determined by atomic absorption spectrophotometry. In addition, the teachers completed an eight-item questionnaire about the children’s behavior and academic achievement. Parents filled in a self-completion survey about the sociodemographic variables of the children and the family.Results: The mean Blood Lead Level (BLL of the children was 4.1 μg/dL SD 1.6 μg/dL (log transformed 3.8 μg/dL SD 0.2 μg/dL. Multivariate analysis controlling for relevant sociodemographic cofactors (among others, sex, age and educational level of the parents showed a negative association, but this was not statistically significant.Conclusions: Despite the low blood lead levels found in the children of the Comunidad de Madrid (Spain and the design limitations of the study, the results obtained suggest the existence of a harmful, but not statistically significant, effect of blood lead on the behavior and academic achievement of children.Objetivos: El plomo en sangre provoca en los niños efectos sobre las funciones cognitivas y sobre el comportamiento. No existe acuerdo sobre los niveles en sangre que evitarían esos efectos.Métodos: Estudio transversal en el que participaron 511 niños pertenecientes a 23 colegios de la Comunidad de Madrid (la ciudad de Madrid y su Corona Metropolitana, España, a los que se les determinaron los niveles de plomo en sangre por espectrofotometría de absorción atómica. Además, los profesores cumplimentaron un cuestionario de ocho preguntas sobre aspectos conductuales y de

  7. Light-induced protein and lipid oxidation in low-fat cheeses: whey proteins as antioxidants

    OpenAIRE

    Dalsgaard, Trine Kastrup; Sørensen, John; Bakman, Mette; Nebel, Caroline; Albrechtsen, Rita; Vognsen, Lene; Nielsen, Jacob Holm

    2011-01-01

    Photo-oxidation of cheese products has become an issue due to the fact that packaging of cheeses in transparent materials is very frequently used. The present study aimed to give new aspects of the possible antioxidative activity of whey proteins in photo-oxidation of cheese and the whey proteins were expected to act as scavenger and thereby reduce lipid oxidation. Oxidation was investigated in low-fat model cheese with whey protein isolate (WPI) added and compared to a low-fat control cheese...

  8. Reading and Math Achievement among Low-Income Urban Latino Youth: The Role of Immigration

    Science.gov (United States)

    Guttmannova, Katarina

    2016-01-01

    Using data from a household-based, stratified random sample of youth and their caregivers from low-income inner-city neighborhoods, this study examined the variability in the academic achievement of Latino youth. The results indicate a significant advantage in reading achievement for first- and second-generation immigrant youth, as compared to the…

  9. Low-quality vegetable oils as feedstock for biodiesel production using K-pumice as solid catalyst. Tolerance of water and free fatty acids contents.

    Science.gov (United States)

    Díaz, L; Borges, M E

    2012-08-15

    Waste oils are a promising alternative feedstock for biodiesel production due to the decrease of the industrial production costs. However, feedstock with high free fatty acids (FFA) content presents several drawbacks when alkaline-catalyzed transesterification reaction is employed in biodiesel production process. Nowadays, to develop suitable processes capable of treating oils with high free fatty acids content, a two-step process for biodiesel production is being investigated. The major problem that it presents is that two catalysts are needed to carry out the whole process: an acidic catalyst for free fatty acids esterification (first step) and a basic catalyst for pretreated product transesterification (second step). The use of a bifunctional catalyst, which allows both reactions to take place simultaneously, could minimize the production costs and time. In the present study, the behavior of pumice, a natural volcanic material used as a heterogeneous catalyst, was tested using oils with several FFA and water contents as feedstock in the transesterification reaction to produce biodiesel. Pumice as a bifunctional solid catalyst, which can catalyze simultaneously the esterification of FFA and the transesterification of fatty acid glycerides into biodiesel, was shown to be an efficient catalyst for the conversion of low-grade, nonedible oil feedstock into biodiesel product. Using this solid catalyst for the transesterification reaction, high FAME yields were achieved when feedstock oils presented a FFA content until approximately 2% wt/wt and a water content until 2% wt/wt. PMID:22799882

  10. 29 CFR 1605.2 - Reasonable accommodation without undue hardship as required by section 701(j) of title VII of the...

    Science.gov (United States)

    2010-07-01

    ... by section 701(j) of title VII of the Civil Rights Act of 1964. 1605.2 Section 1605.2 Labor...) of title VII of the Civil Rights Act of 1964. (a) Purpose of this section. This section clarifies the obligation imposed by title VII of the Civil Rights Act of 1964, as amended, (sections 701(j), 703 and...

  11. Constructivism as a Model for Cognitive Development and (Eventually) Learning (Orange Juice Experiment): The Development of Proportional Reasoning in the Child and Adolescent.

    Science.gov (United States)

    Noelting, Gerald

    This study examined the development of the rational number concept as a ratio. Preliminary to the description of the study is an introduction discussing constructivism and equilibration. The study itself tests whether equilibration theory holds, and if so, what is the nature of its "phases" and whether these are found at each of the "periods" of…

  12. Dark acoustic metamaterials as super absorbers for low-frequency sound.

    Science.gov (United States)

    Mei, Jun; Ma, Guancong; Yang, Min; Yang, Zhiyu; Wen, Weijia; Sheng, Ping

    2012-01-01

    The attenuation of low-frequency sound has been a challenging task because the intrinsic dissipation of materials is inherently weak in this regime. Here we present a thin-film acoustic metamaterial, comprising an elastic membrane decorated with asymmetric rigid platelets that aims to totally absorb low-frequency airborne sound at selective resonance frequencies ranging from 100-1,000 Hz. Our samples can reach almost unity absorption at frequencies where the relevant sound wavelength in air is three orders of magnitude larger than the membrane thickness. At resonances, the flapping motion of the rigid platelets leads naturally to large elastic curvature energy density at their perimeter regions. As the flapping motions couple only minimally to the radiation modes, the overall energy density in the membrane can be two-to-three orders of magnitude larger than the incident wave energy density at low frequencies, forming in essence an open cavity. PMID:22453829

  13. A comparison of concrete and formal science instruction upon science achievement and reasoning ability of sixth grade students

    Science.gov (United States)

    Saunders, Walter L.; Shepardson, Daniel

    Several recent studies suggest concrete learners make greater gains in student achievement and in cognitive development when receiving concrete instruction than when receiving formal instruction. This study examined the effect of concrete and formal instruction upon reasoning and science achievement of sixth grade students. Four intact classes of sixth grade students were randomly selected into two treatment groups; concrete and formal. The treatments were patterned after the operational definitions published by Schneider and Renner (1980). Pretest and posttest measures were taken on the two dependent variables; reasoning, measured with Lawson's Classroom Test of Formal Reasoning, and science achievement, measured with seven teacher made tests covering the following units in a sixth grade general science curriculum: Chemistry, Physics, Earth Science, Cells, Plants, Animals, and Ecology. Analysis of covariance indicated significantly higher levels (better than 0.05 and in some cases 0.01) of performance in science achievement and cognitive development favoring the concrete instruction group and a significant gender effect favoring males.

  14. Asynchronous interaction, online technologies self-efficacy and self-regulated learning as predictors of academic achievement in an online class

    Science.gov (United States)

    McGhee, Rosie M. Hector

    This research is a correlational study of the relationship among the independent variables: asynchronous interaction, online technologies self-efficacy, and self-regulated learning, and the dependent variable; academic achievement. This study involves an online computer literacy course at a local community college. Very little research exists on the relationship among asynchronous interaction, online technologies self-efficacy and self-regulated learning on predicting academic achievement in an online class. Liu (2008), in his study on student interaction in online courses, concluded that student interaction is a complex issue that needs more research to increase our understanding as it relates to distance education. The purpose of this study was to examine the relationships between asynchronous interaction, online technologies self-efficacy, self-regulated learning and academic achievement in an online computer literacy class at a community college. The researcher used quantitative methods to obtain and analyze data on the relationships among the variables during the summer 2010 semester. Forty-five community college students completed three web-based self-reporting instruments: (a) the GVU 10th WWW User Survey Questionnaire, (b) the Online Technologies Self-Efficacy Survey, and (c) selected items from the Motivated Strategies for Learning Questionnaire. Additional data was obtained from asynchronous discussions posted on Blackboard(TM) Learning Management System. The results of this study found that there were statistically significant relationships between asynchronous interaction and academic achievement (r = .55, p self-regulated learning and academic achievement ( r = -.02, p learning experience. Driscoll (2005) said constructivist pedagogy sees the learner as an active participant in their learning experience rather than a passive vessel to be filled with information. This study is beneficial to theorists, administrators, leaders, online instructors, online

  15. A low noise low power 512×256 ROIC for extended wavelength InGaAs FPA

    Science.gov (United States)

    Huang, Songlei; Huang, Zhangcheng; Chen, Yu; Li, Tao; Fang, Jiaxiong

    2015-05-01

    A low noise low power 512×256 readout integrated circuit (ROIC) based on Capacitance Trans-impedance Amplifier (CTIA) was designed in this paper. The ROIC with 30μm pixel-pitch and 70 fF integrated capacitance as normal structure and test structure capacitance from 5 to 60 fF, was fabricated in 0.5μm DPTM CMOS process. The results showed that output voltage was larger than 2.0V and power consumption was about 150mW, output ROIC noise was about 3.6E-4V which equivalent noise was 160e-, and the test structure noise was from 20e- to 140 e-. Compared the readout noises in Integration Then Readout (ITR) mode and Integration While Readout (IWR) mode, it indicated that in IWR mode, readout noise comes mainly from both integration capacitance and sampling capacitance, while in ITR mode, readout noise comes mostly from sampling capacitance. Finally the ROIC was flip-chip bonded with Indium bumps to extended wavelength InGaAs detectors with cutoff wavelength 2.5μm at 200K. The peak detectivity exceeded 5E11cmHz1/2/w with 70nA/cm2 dark current density at 200K.

  16. Accelerated fuel depreciation as an economic incentive for low-leakage fuel management

    International Nuclear Information System (INIS)

    An analysis is presented which evaluates the tax depreciation advantage which results from the increased rate of fuel depletion achieved in the current low-leakage fuel-management LWR core reload designs. An analytical fuel-cycle cost model is used to examine the important cost parameters which are then validated using the fuel-cycle cost code CINCAS and data from the Maine Yankee PWR. Results show that low-leakage fuel management, through the tax depreciation advantage from accelerated fuel depletion, provides an improvement of several percent in fuel-cycle costs compared to traditional out-in fuel management and a constant fuel depletion rate. (author)

  17. Microbial fuel cells as power supply of a low-power temperature sensor

    Science.gov (United States)

    Khaled, Firas; Ondel, Olivier; Allard, Bruno

    2016-02-01

    Microbial fuel cells (MFCs) show great promise as a concomitant process for water treatment and as renewable energy sources for environmental sensors. The small energy produced by MFCs and the low output voltage limit the applications of MFCs. Specific converter topologies are required to step-up the output voltage of a MFC. A Power Management Unit (PMU) is proposed for operation at low input voltage and at very low power in a completely autonomous way to capture energy from MFCs with the highest possible efficiency. The application of sensors for monitoring systems in remote locations is an important approach. MFCs could be an alternative energy source in this case. Powering a sensor with MFCs may prove the fact that wastewater may be partly turned into renewable energy for realistic applications. The Power Management Unit is demonstrated for 3.6 V output voltage at 1 mW continuous power, based on a low-cost 0.7-L MFC. A temperature sensor may operate continuously on 2-MFCs in continuous flow mode. A flyback converter under discontinuous conduction mode is also tested to power the sensor. One continuously fed MFC was able to efficiently and continuously power the sensor.

  18. Optimization of low sulfur carob pulp liquor as carbon source for fossil fuels biodesulfurization

    OpenAIRE

    Silva, Tiago P.; Paixão, Susana M.; Teixeira, A. V.; Roseiro, J. Carlos; Alves, Luís Manuel

    2013-01-01

    Background:Biodesulfurization (BDS) is a complementary technology to hydrodesulfurization since it allows the removal of recalcitrant sulfur compounds present in fossil fuels. The cost of culture medium to produce the biocatalysts is still one limitation for BDS application. Carob pulp, as an alternative carbon source, can reduce this cost. However, the presence of sulfates is critical, since BDS is inhibited at very low concentrations. Thus, the goal of this work was to optimize the process ...

  19. Surfactant-free CZTS nanoparticles as building blocks for low-cost solar cell absorbers

    OpenAIRE

    Zaberca, Oana; Oftinger, Frédéric; Chane-Ching, Jean-Yves; Datas, Lucien; Lafond, Alain; Puech, Pascal; Balocchi, Andréa; Lagarde, Delphine; Marie, Xavier

    2012-01-01

    A process route for the fabrication of solvent-redispersible, surfactant-free Cu2ZnSnS4 (CZTS) nanoparticles has been designed with the objective to have the benefit of a simple sulfide source which advantageously acts as (i) a complexing agent inhibiting crystallite growth, (ii) a surface additive providing redispersion in low ionic strength polar solvents and (iii) a transient ligand easily replaced by an carbon-free surface additive. This multifunctional use of the sulfide source has been ...

  20. Renewable and low-carbon energies as mitigation options of climate change for China

    OpenAIRE

    Urban, F.; Benders, R.M.J.; Moll, H.C.

    2009-01-01

    This article discusses how renewable and low-carbon energies can serve as mitigation options of climate change in China's power sector. Our study is based on scenarios developed in PowerPlan, a bottom-up model simulating a countries' power sector and its emissions. We first adjusted the model to China's present-day economy and power sector. We then developed different scenarios based on story lines for possible future developments in China. We simulated China's carbon-based electricity produc...

  1. Graphite Isotope Ratio Method Development Report: Irradiation Test Demonstration of Uranium as a Low Fluence Indicator

    International Nuclear Information System (INIS)

    This report describes an irradiation test designed to investigate the suitability of uranium as a graphite isotope ratio method (GIRM) low fluence indicator. GIRM is a demonstrated concept that gives a graphite-moderated reactor's lifetime production based on measuring changes in the isotopic ratio of elements known to exist in trace quantities within reactor-grade graphite. Appendix I of this report provides a tutorial on the GIRM concept

  2. Low Cost Robots as Target System for Students Training Using Java

    OpenAIRE

    Olaf Hallan Graven; Dag Andreas Hals Samuelsen

    2009-01-01

    The topic of this paper is a cost efficient programming environment designed with a focus on enhancing the students’ engagement and effort to complete the assignments. The environment is designed to give the students an approach that is similar to a professional work situation with respect to hardware-software interaction, documentation and complexity. The system presented is based on low-cost, off-the-shelf equipment for easy implementation on mass in an educational institution. As part of t...

  3. Hair as Biomarker of Fluoride Exposure in a Fluoride Endemic Area and a Low Fluoridated Area

    OpenAIRE

    Parimi, Nalini; V. Viswanath; Kashyap, Bina; Patil, Pavan Uday

    2013-01-01

    Aim: The aim of the present study was to determine whether hair could be used as biomarker of fluoride exposure. Materials and Methods: The study was carried out on 30 people living in an endemically fluoridated area and a low fluoridated area. Samples of hair from the occipital were taken and subjected to fluoride analysis by a fluoride ion electrode. Results: Lower fluoride levels in water supplies correlated with lower levels of fluoride in hair and more over higher fluoride levels in wate...

  4. What's Wrong with News-Editorial (Print) Journalism? Students Reject It as a Curriculum or Career Path and State Their Reasons.

    Science.gov (United States)

    Mann, Raleigh C.; And Others

    The ratio of journalism students choosing advertising to those choosing a news-editorial emphasis has risen dramatically in the 1980s. To determine whether students are rejecting the news-editorial curriculum based on their beliefs that occupations in this field offer low salaries, poor working conditions, and less creative opportunity than…

  5. TRPV Channels in Mast Cells as a Target for Low-Level-Laser Therapy

    Directory of Open Access Journals (Sweden)

    Lina Wang

    2014-06-01

    Full Text Available Low-level laser irradiation in the visible as well as infrared range is applied to skin for treatment of various diseases. Here we summarize and discuss effects of laser irradiation on mast cells that leads to degranulation of the cells. This process may contribute to initial steps in the final medical effects. We suggest that activation of TRPV channels in the mast cells forms a basis for the underlying mechanisms and that released ATP and histamine may be putative mediators for therapeutic effects.

  6. Low- and high-mode separation of short wavelength turbulence in dithering Wendelstein 7-AS plasmas

    DEFF Research Database (Denmark)

    Basse, N.P.; Zoletnik, S.; Saffman, M.;

    2002-01-01

    In this article measurements of small scale electron density fluctuations in dithering high confinement (H)-mode plasmas obtained by collective scattering of infrared light are presented. A scan of the fluctuation wavenumber was made in a series of similar discharges in the Wendelstein 7-AS (W7-AS......) stellarator [H. Renner , Plasma Phys. Control. Fusion 31, 1579 (1989)]. The experimental setup and discharge properties are described. H-alpha-light observing an inner limiter was used to separate low confinement (L)- and H-mode phases of the plasma; the separated density fluctuations are characterized. It...

  7. Investigation of defects produced by low energy As+ implantation in Si(100)

    International Nuclear Information System (INIS)

    Si(100) samples were implanted with low energy As+ ions at different incident angles and followed by rapid thermal annealing. The defects in Si(100) were measured by Doppler broadening of positron annihilation. The distribution of defects is solved by simulating a one dimensional diffusion equation. The density of defects produced by 15 degree implantation of As+ is higher than that by 60 degree implantation, and the types of defects are different. The defects produced by 15 degree implantation can be eliminated effectively by rapid thermal annealing

  8. Composite hemangioendothelioma and its classification as a low-grade malignancy.

    Science.gov (United States)

    McNab, Patricia Moody; Quigley, Brian Christopher; Glass, L Frank; Jukic, Drazen M

    2013-06-01

    Hemangioendotheliomas are vascular neoplasms occupying a spectrum of biological potential ranging from benign to low-grade malignancy. Composite hemangioendothelioma (CH) is one of the less commonly encountered variants exhibiting a mixture of elements of other hemangioendothelioma subtypes, such as epithelioid, retiform, and spindle cell. Some authors have identified areas histopathologically equivalent to angiosarcoma within CH, raising the question of the true nature of this neoplasm. Although CH recurs locally, there are only 3 reported cases which metastasized. To date, 26 cases (including the present case) have been described in the literature. Herein, we describe a unique case of CH arising in the background of previous radiation therapy and long-standing lymphedema (classically associated with the development of angiosarcoma-Stewart-Treves syndrome) that harbored higher grade areas but behaved as a low-grade malignant neoplasm. This, in conjunction with the many reported cases of CH-harboring angiosarcoma-like areas, and the occasional association with a history of lymphedema, raises the question of whether this variant of hemangioendothelioma may actually be an angiosarcoma that behaves prognostically better than the conventional type. After careful study of the natural disease progression of the current case and review of the literature, we discuss justification for the continued classification of CH as a low-grade malignancy. PMID:23694827

  9. Isopropanol dehydration via extractive distillation using low transition temperature mixtures as entrainers

    International Nuclear Information System (INIS)

    Highlights: • Low transition temperature mixtures (LTTMs) were used for the (isopropanol + water) separation. • (Vapor + liquid) equilibrium (VLE) data of pseudo-binary and pseudo-ternary systems were measured. • The VLE data were successfully correlated using the NRTL model. • (Glycolic acid + choline chloride) (molar ratio = 3:1) showed the largest azeotrope displacement. - Abstract: Low transition temperature mixtures (LTTMs), also known as deep eutectic solvents, show properties that make them suitable as entrainers for extractive distillation. Two different low transition temperature mixtures were considered as potential entrainers for the extractive distillation of the azeotropic mixture (isopropanol + water). (Lactic acid + choline chloride) (2:1) and (glycolic acid + choline chloride) (3:1) were selected for this work. (Vapor + liquid) equilibrium measurements of the pseudo-binary systems (isopropanol + LTTM) and (water + LTTM) were measured at different concentrations of LTTM in a pressure range of 10 to 100 kPa. (Vapor + liquid) equilibrium data of the pseudo-ternary system (isopropanol + water + LTTM) were also measured at constant pressure (100 kPa) and constant LTTM molar fraction of 0.05 and 0.1. It was found that these LTTMs cannot break the azeotrope at those concentrations. However, the azeotrope was displaced to a much higher isopropanol concentration. The NRTL model was successfully applied to fit the experimental data

  10. Observation versus antiplatelet therapy as primary prophylaxis for thrombosis in low-risk essential thrombocythemia.

    Science.gov (United States)

    Alvarez-Larrán, Alberto; Cervantes, Francisco; Pereira, Arturo; Arellano-Rodrigo, Eduardo; Pérez-Andreu, Virginia; Hernández-Boluda, Juan-Carlos; Ayats, Ramón; Salvador, Carlos; Muntañola, Ana; Bellosillo, Beatriz; Vicente, Vicente; Hernández-Nieto, Luis; Burgaleta, Carmen; Xicoy, Blanca; Besses, Carlos

    2010-08-26

    The effectiveness of antiplatelet therapy as primary prophylaxis for thrombosis in low-risk essential thrombocythemia (ET) is not proven. In this study, the incidence rates of arterial and venous thrombosis were retrospectively analyzed in 300 low-risk patients with ET treated with antiplatelet drugs as monotherapy (n = 198) or followed with careful observation (n = 102). Follow-up was 802 and 848 person-years for antiplatelet therapy and observation, respectively. Rates of thrombotic events were 21.2 and 17.7 per 1000 person-years for antiplatelet therapy and observation, respectively (P = .6). JAK2 V617F-positive patients not receiving antiplatelet medication showed an increased risk of venous thrombosis (incidence rate ratio [IRR]: 4.0; 95% CI: 1.2-12.9; P = .02). Patients with cardiovascular risk factors had increased rates of arterial thrombosis while on observation (IRR: 2.5; 95% CI: 1.02-6.1; P = .047). An increased risk of major bleeding was observed in patients with platelet count greater than 1000 x 10(9)/L under antiplatelet therapy (IRR: 5.4; 95% CI: 1.7-17.2; P = .004). In conclusion, antiplatelet therapy reduces the incidence of venous thrombosis in patients with JAK2-positive ET and the rate of arterial thrombosis in patients with associated cardiovascular risk factors. In the remaining low-risk patients, this therapy is not effective as primary prophylaxis of thrombosis, and observation may be an adequate option. PMID:20508163

  11. "理性人"标准作为事故过失责任认定标准的经济分析%Economic Analysis Regarding the Reasonable Person Standard as the Accident Negligence Responsibility Determination Standard

    Institute of Scientific and Technical Information of China (English)

    熊春泉; 张静

    2009-01-01

    以"理性人"标准作为事故过失责任认定,实质上是以"理性人"的注意水平来确定过失之有无."理性人"标准下会导致分配成本不当之后果,但放弃个别标准带来的分配所得换取成本的减少是有效率的;在弱的意义上看,"理性人"标准下过失责任会比严格责任事故数量少."理性人"标准与个别标准两者权衡时,应遵循:当决定一个人应尽注意水平的成本较低或若用减少引起事故的行为代替增加注意的可行性越强,背离"理性人"标准很可能是不允许的.%Regarding the reasonable person standard as the accident negligence responsibility determina-tion standard is in fact to determine negligence or not by the attention level of the reasonable person. There seems the phenomenon of distribution cost improper under the reasonable person standard, but dis-tributive income obtained at the cost of giving up the individual standard, in exchange for the reduce of cost, which is effective. The quantity of negligence responsibility accident is less than that of strict respon-sibihty accident under the reasonable person standard. When weighing the reasonable person standard and the individual standard, we should follow: when deciding a person should decrease the cost of the attention level as much as possible, or the feasibility which the accident act instead of increase attention by decreas-ing is stronger, the standard of deviating from the reasonable person is probably impermissible.

  12. Clinical Trials Infrastructure as a Quality Improvement Intervention in Low- and Middle-Income Countries.

    Science.gov (United States)

    Denburg, Avram; Rodriguez-Galindo, Carlos; Joffe, Steven

    2016-06-01

    Mounting evidence suggests that participation in clinical trials confers neither advantage nor disadvantage on those enrolled. Narrow focus on the question of a "trial effect," however, distracts from a broader mechanism by which patients may benefit from ongoing clinical research. We hypothesize that the existence of clinical trials infrastructure-the organizational culture, systems, and expertise that develop as a product of sustained participation in cooperative clinical trials research-may function as a quality improvement lever, improving the quality of care and outcomes of all patients within an institution or region independent of their individual participation in trials. We further contend that this "infrastructure effect" can yield particular benefits for patients in low- and middle-income countries (LMICs). The hypothesis of an infrastructure effect as a quality improvement intervention, if correct, justifies enhanced research capacity in LMIC as a pillar of health system development. PMID:27216089

  13. Studies on Some Nitramine based Low Vulnerability Ammunition Propellants with Cellulose Acetate as a Binder

    Directory of Open Access Journals (Sweden)

    A.G.A. Pillai

    1996-04-01

    Full Text Available Several formulations of propellants based on RDX as an energetic solid ingredients and cellulose acetate (CA as a binder were processed using either dioctyl pthalate(DOP or tracetin(TA as plastisizer and a small amount of nitrocellulose(NC. The Performance of these propellants was evaluated on the basis of closed vessel firing data. The vulnerability aspects of these formulations were compared with those of conventional picrite propellant, NQ on the basis of their ignition temperatures and sensitivity to friction and impact. Triacetin was found to be better plasticizer than DOP for CA binder. Some RDX/CA/TA/NC/-based propellants were found to have energy levels comparable with NQ propellant and had less sensitivity to heat, impact and friction, and therefore have the potential for being used as low-vulnerability ammunition propellants for gun applications.

  14. High-peak-power low-threshold AlGaAs/GaAs stripe laser diodes on Si substrates grown by migration-enhanced molecular beam epitaxy

    Science.gov (United States)

    Kim, Jae-Hoon; Nouhi, Akbar; Radhakrishnan, Gouri; Liu, John K.; Lang, Robert J.

    1988-01-01

    A high-peak-power low-threshold AlGaAs/GaAs double-heterostructure stripe laser diode on Si substrats, grown by hybrid migration-enhanced molecular beam epitaxy (MEMBE) and metalorganic chemical vapor deposition (MOCVD) has been demonstrated for the first time. These devices showed the highest peak powers of up to 184 mW per facet reported so far for double-heterostructure stripe laser diodes on Si substrates, room-temperature pulsed threshold currents as low as 150 mA, and differential quantum efficiencies as high as 30 percent without mirror facet coating. An intrinsic threshold current density has been estimated to be about 2 kA/sq cm when taking current spreading and lateral diffusion effects into account. Low dislocation density shows that MEMBE can be a useful method to grow high-quality GaAs and AlGaAs/GaAs layers on Si substrates by combining with MOCVD.

  15. Constrained sessile drop as a new configuration to measure low surface tension in lung surfactant systems.

    Science.gov (United States)

    Yu, Laura M Y; Lu, James J; Chan, Yawen W; Ng, Amy; Zhang, Ling; Hoorfar, Mina; Policova, Zdenka; Grundke, Karina; Neumann, A Wilhelm

    2004-08-01

    Existing methodology for surface tension measurements based on drop shapes suffers from the shortcoming that it is not capable to function at very low surface tension if the liquid dispersion is opaque, such as therapeutic lung surfactants at clinically relevant concentrations. The novel configuration proposed here removes the two big restrictions, i.e., the film leakage problem that is encountered with such methods as the pulsating bubble surfactometer as well as the pendant drop arrangement, and the problem of the opaqueness of the liquid, as in the original captive bubble arrangement. A sharp knife edge is the key design feature in the constrained sessile drop that avoids film leakage at low surface tension. The use of the constrained sessile drop configuration in conjunction with axisymmetric drop shape analysis to measure surface tension allows complete automation of the setup. Dynamic studies with lung surfactant can be performed readily by changing the volume of a sessile drop, and thus the surface area, by means of a motor-driven syringe. To illustrate the validity of using this configuration, experiments were performed using an exogenous lung surfactant preparation, bovine lipid extract surfactant (BLES) at 5.0 mg/ml. A comparison of results obtained for BLES at low concentration between the constrained sessile drop and captive bubble arrangement shows excellent agreement between the two approaches. When the surface area of the BLES film (0.5 mg/ml) was compressed by about the same amount in both systems, the minimum surface tensions attained were identical within the 95% confidence limits. PMID:15064296

  16. RELATIONSHIP BETWEEN WEB-BASED LEARNING TIME OUTSIDE THE CLASSROOM AND ACADEMIC ACHIEVEMENT IN GERMAN AS A TERTIARY LANGUAGE BY THE STUDENTS ON VOCATIONAL HIGH SCHOOLS

    Directory of Open Access Journals (Sweden)

    Orhan HANBAY

    2013-01-01

    Full Text Available The purpose of this empirical research is to investigate the relationship between web-based learning time and academic achievement in German. 36 learners of L3 German with L1 Turkish and L2 English from Vocational High School of Kahta at Adiyaman University were the participants of this study. The empirical process of the study continued 6 weeks in 2011-2012 fall semesters. During this time, the German, as tertiary language, course was lectured by traditional face-to-face method in the classroom. But the students studied outside the course the same subjects in interactive form via web page, specifically designed for this study. At the end of the empirical process, the data about the study were obtained. The Pearson product-moment correlation was used to find out the relationship between web-based learning time and academic achievements in German. As a result of this study it is found out that there is a significant relationship between web-based learning time and academic achievement in German as a tertiary language.

  17. Emotional intelligence as a predictor of self-efficacy among students with different levels of academic achievement at Kermanshah University of Medical Sciences

    Directory of Open Access Journals (Sweden)

    AMENEH GHARETEPEH

    2015-04-01

    Full Text Available Introduction: studies have indicated that emotional intelligence is positively related to self-efficacy and can predict the academic achievement. The present study aimed to investigate the role of emotional intelligence in identifying self-efficacy among the students of Public Health School with different levels of academic achievement. Methods: This correlational study was conducted on all the students of Public Health School. 129 students were included in the study through census method. Data were collected using Emotional Intelligence and self-efficacy questionnaires and analyzed using descriptive statistics and regression analysis by SPSS 14. Results: The average score of students with high academic achievement was higher in self-efficacy (39.78±5.82 and emotional intelligence (117.07±10.33 variables and their components than that of students with low academic achievement (39.17±5.91, 112.07±13.23. The overall emotional intelligence score to predict self-efficacy explanation was different among students with different levels of academic achievement (p<0.001. Self-efficacy structure was explained through self-awareness and self-motivation components in students with low academic achievement (r=0.571. In students with high academic achievement, self-awareness, selfmotivation and social consciousness played an effective role in explaining self-efficacy (r=0.677, p<0.001. Conclusion: Emotional intelligence and self-efficacy play an important role in achieving academic success and emotional intelligence can explain self-efficacy. Therefore, it is recommended to teach emotional intelligence skills to students with low academic achievement through training workshops.

  18. Emesis as a Screening Diagnostic for Low Dose Rate (LDR) Total Body Radiation Exposure.

    Science.gov (United States)

    Camarata, Andrew S; Switchenko, Jeffrey M; Demidenko, Eugene; Flood, Ann B; Swartz, Harold M; Ali, Arif N

    2016-04-01

    Current radiation disaster manuals list the time-to-emesis (TE) as the key triage indicator of radiation dose. The data used to support TE recommendations were derived primarily from nearly instantaneous, high dose-rate exposures as part of variable condition accident databases. To date, there has not been a systematic differentiation between triage dose estimates associated with high and low dose rate (LDR) exposures, even though it is likely that after a nuclear detonation or radiologic disaster, many surviving casualties would have received a significant portion of their total exposure from fallout (LDR exposure) rather than from the initial nuclear detonation or criticality event (high dose rate exposure). This commentary discusses the issues surrounding the use of emesis as a screening diagnostic for radiation dose after LDR exposure. As part of this discussion, previously published clinical data on emesis after LDR total body irradiation (TBI) is statistically re-analyzed as an illustration of the complexity of the issue and confounding factors. This previously published data includes 107 patients who underwent TBI up to 10.5 Gy in a single fraction delivered over several hours at 0.02 to 0.04 Gy min. Estimates based on these data for the sensitivity of emesis as a screening diagnostic for the low dose rate radiation exposure range from 57.1% to 76.6%, and the estimates for specificity range from 87.5% to 99.4%. Though the original data contain multiple confounding factors, the evidence regarding sensitivity suggests that emesis appears to be quite poor as a medical screening diagnostic for LDR exposures. PMID:26910032

  19. Outgassing characteristics of F82H ferritic steel as a low activation material for fusion reactor

    Energy Technology Data Exchange (ETDEWEB)

    Odaka, Kenji; Satou, Osamu [Hitachi Ltd., Tsuchiura, Ibaraki (Japan). Mechanical Engineering Research Lab.; Ootsuka, Michio; Abe, Tetsuya; Hara, Shigemitsu; Takatsu, Hideyuki; Enoeda, Mikio

    1997-09-01

    Outgassing characteristics of F82H ferritic steel as a low activation material for the blanket of fusion device were investigated. A test chamber was constructed by welding F82H ferritic steel plates. The inner surface of the chamber was buffed and electropolished. The test chamber was degassed by the prebaking at temperature of 350degC for 20 h in vacuum. Then outgassing rates of the test chamber were measured by the throughput method as a function of pumping time for the cases that the test chamber was baked and not baked. The typical outgassing rate after baking at 250degC for 24 h was 3 x 10{sup -9} Pa{center_dot}ms{sup -1} and it seems that this value is sufficiently small to produce pressures at least as low as 10{sup -9} Pa in the vacuum chamber made of F82H ferritic steel. In the pump-down of the test chamber without baking after exposure to air, the outgassing rate decreases with pumping time and reached 1 x 10{sup -7} Pa{center_dot}ms{sup -1} at t = 10{sup 5} s. The activation energy of hydrogen in bulk diffusion in the F82H ferritic steel was measured and found to be 7 kcal/mol. (author)

  20. Low-carbon communities as a context for individual behavioural change

    International Nuclear Information System (INIS)

    Previous attempts to change energy-related behaviour were targeted at individuals as consumers of energy. Recent literature has suggested that more focus should be placed on the community level and that energy users should be engaged in the role of citizens, and not only that of consumers. This article analyses different types of emerging low-carbon communities as a context for individual behavioural change. The focus is on how these communities offer solutions to problems in previous attempts to change individual behaviour. These problems include social dilemmas, social conventions, socio-technical infrastructures and the helplessness of individuals. Different community types are examined, including geographical communities as well as sector-based, interest-based and smart mob communities. Through four case studies representing each of these community types, we examine how different communities reframe problems on the individual level to reduce carbon emissions. On the basis of an analysis of the strengths and weaknesses of various community solutions, implications are drawn for further research and for the design and support of low-carbon communities.