WorldWideScience

Sample records for cells history principle

  1. History and Principles of Humanitarian Action.

    Science.gov (United States)

    Rysaback-Smith, Heather

    2015-10-01

    Humanitarian aid has been present in some form throughout human history, yet the modern concept of humanitarian aid has only truly emerged since the later half of the 20th century. Through a complex progression of world events and largely brought about in response to armed conflict, modern humanitarian aid is provided by a multitude of organizations and actors. The purpose of this chapter is to provide a brief overview of the history of humanitarian action, a review of the principles of humanitarian aid and an overview of the major documents which delineate those principles. PMID:27437525

  2. [The history of anesthesia apparatus: basic principles].

    Science.gov (United States)

    Wawersik, J

    1982-10-01

    The beginnings of modern anesthetic equipment date back to Morton's inhalation flagon in 1846. The numerous devices developed and introduced subsequently can be divided into four groups: 1. Simple ether and chloroform masks for open inhalation anesthesia, from Simpson (1847) to Brown (1928). 2. Vapour inhalators according to the "draw over" principle of Snow (1847) up to the Oxford vaporizer (1941). 3. Closed or half-closed inhalation equipment for ether or chloroform with to and fro breathing, from Clover (1877) to Ombredanne (1908). 4. Equipment for anaesthesia with nitrous oxide. From 1868 onwards this led to the incorporation of gas bottles in anaesthetic equipment and between 1885 and 1890 to the construction of mixing-valves for nitrous oxide and oxygen. In addition, reducing valves, flow meters and vaporizers were developed. The first anaesthetic apparatus with circle system and CO2-absorber was constructed in 1925 by the Dräger factory in Lübeck. Sudeck and Schmidt introduced this technique of anaesthesia in the university hospital of Hamburg-Eppendorf between 1920 and 1925. PMID:6758628

  3. Geothermal systems: Principles and case histories

    Science.gov (United States)

    Rybach, L.; Muffler, L. J. P.

    The classification of geothermal systems is considered along with the geophysical and geochemical signatures of geothermal systems, aspects of conductive heat transfer and regional heat flow, and geothermal anomalies and their plate tectonic framework. An investigation of convective heat and mass transfer in hydrothermal systems is conducted, taking into account the mathematical modelling of hydrothermal systems, aspects of idealized convective heat and mass transport, plausible models of geothermal reservoirs, and preproduction models of hydrothermal systems. Attention is given to the prospecting for geothermal resources, the application of water geochemistry to geothermal exploration and reservoir engineering, heat extraction from geothermal reservoirs, questions of geothermal resource assessment, and environmental aspects of geothermal energy development. A description is presented of a number of case histories, taking into account the low enthalpy geothermal resource of the Pannonian Basin in Hungary, the Krafla geothermal field in Northeast Iceland, the geothermal system of the Jemez Mountains in New Mexico, and extraction-reinjection at the Ahuachapan geothermal field in El Salvador.

  4. Chemoprevention--history and general principles.

    Science.gov (United States)

    Wu, Xiangwei; Patterson, Sherri; Hawk, Ernest

    2011-08-01

    Our current understanding of tumourigenesis suggests that cancer develops as a series of cumulative genetic and epigenetic derangements across time culminating in a clone of cells differing from its population of origin in terms of cellular identity, growth control, and its contextual relationship to its environment. Our increasing knowledge of the timing, sequence, frequency, and specific implications of these changes provides unique opportunities for earlier identification of aberrations and preventive interventions. Here we discuss the fundamentals of cancer prevention including the targets, cohorts, agents, endpoints, mechanistic biomarkers, designs, and strategies employed in preventive drug development. There have been many notable successes in this field such as the identification and development of tamoxifen and raloxifene for breast cancer risk reduction, instillational BCG and valrubicin for treatment of preinvasive bladder cancer, and a variety of topical and systemic agents that effectively treat preinvasive neoplastic lesions of the skin. A variety of null or negative developmental endeavours have occurred as well, including trials of beta-carotene for lung cancer prevention, nutritional modifications for colorectal adenoma prevention, and most recently, selenium and alpha-tocopherol for prostate cancer prevention. A third category of prevention trials can be summarized as investigationally successful, but not achieving regulatory success. The development of finasteride and dutasteride for prostate cancer prevention, and celecoxib for colorectal neoplasia prevention fall into this category. In less than four decades, cancer chemoprevention has transformed from a concept to an achievable reality. PMID:22122762

  5. Cell tracking. Principles and applications

    International Nuclear Information System (INIS)

    Cell based therapies such as stem cell therapies or adoptive immunotherapies are currently being explored as a potential treatment for a variety of diseases such as Parkinson's disease, diabetes or cancer. However, quantitative and qualitative evaluation of adoptively transferred cells is indispensable for monitoring the efficiency of the treatment. Current approaches mostly analyze transferred cells from peripheral blood, which cannot assess whether transferred cells actuallyhome to and stay in the targeted tissue. Using cell-labeling methods such as direct labeling or transfection with a marker gene in conjunction with various imaging modalities (MRI, optical or nuclear imaging), labeled cells can be followed in vivo in real-time, and their accumulation as well as function in vivo can be monitored and quantified accurately. This method is usually referred to as ''cell tracking'' or ''cell trafficking'' and is also being applied in basic biological sciences, exemplified in the evaluation of genes contributing to metastasis. This review focuses on principles of this promising methodology and explains various approaches by highlighting recent examples. (orig.)

  6. The history, principles and application of the IAEA Transport Regulations

    International Nuclear Information System (INIS)

    A brief background to and history of the IAEA Transport Regulations are presented. The principles underlying the Regulations are outlined. The structure and general contents of the 1985 edition of the Regulations and its differences from earlier editions are discussed in detail. Changes occurring in the 1986 supplement to the 1985 edition of the IAEA Transport Regulations are summarised. The adoption and application of the Regulations worldwide is described briefly. 3 tabs

  7. Orff Music Therapy: History, Principles and Further Development

    OpenAIRE

    Melanie Voigt

    2013-01-01

    Orff Music Therapy, a developmental approach to music therapy, was developed by Gertrud Orff within the framework of social paediatrics in Munich, Germany. A short historical background of Orff Music Therapy is discussed. The history of the clinical setting in which it was developed is described as is Gertrud Orff’s professional background. The role of Orff-Schulwerk in Orff Music Therapy and the development of theoretical foundations are discussed. Current principles and practice of Orff Mus...

  8. Orff Music Therapy: History, Principles and Further Development

    Directory of Open Access Journals (Sweden)

    Melanie Voigt

    2013-12-01

    Full Text Available Orff Music Therapy, a developmental approach to music therapy, was developed by Gertrud Orff within the framework of social paediatrics in Munich, Germany. A short historical background of Orff Music Therapy is discussed. The history of the clinical setting in which it was developed is described as is Gertrud Orff’s professional background. The role of Orff-Schulwerk in Orff Music Therapy and the development of theoretical foundations are discussed. Current principles and practice of Orff Music Therapy, illustrated by a case example show how the profile of Orff Music Therapy has developed. On the basis of the case example, theory is related to practice. Finally, changes influencing Orff Music Therapy today, training and research are considered.

  9. Collective cell migration: guidance principles and hierarchies.

    Science.gov (United States)

    Haeger, Anna; Wolf, Katarina; Zegers, Mirjam M; Friedl, Peter

    2015-09-01

    Collective cell migration results from the establishment and maintenance of collective polarization, mechanocoupling, and cytoskeletal kinetics. The guidance of collective cell migration depends on a reciprocal process between cell-intrinsic multicellular organization with leader-follower cell behavior and results in mechanosensory integration of extracellular guidance cues. Important guidance mechanisms include chemotaxis, haptotaxis, durotaxis, and strain-induced mechanosensing to move cell groups along interfaces and paths of least resistance. Additional guidance mechanisms steering cell groups during specialized conditions comprise electrotaxis and passive drift. To form higher-order cell and tissue structures during morphogenesis and cancer invasion, these guidance principles act in parallel and are integrated for collective adaptation to and shaping of varying tissue environments. We review mechanochemical and electrical inputs and multiparameter signal integration underlying collective guidance, decision making, and outcome. PMID:26137890

  10. Tracing organizing principles: Learning from the history of systems biology

    DEFF Research Database (Denmark)

    Green, Sara; Wolkenhauer, Olaf

    2014-01-01

    With the emergence of systems biology, the identification of organizing principles is being highlighted as a key research aim. Researchers attempt to “reverse engineer” the functional organization of biological systems using methodologies from mathematics, engineering and computer science while...

  11. Stem cell bioprocessing: fundamentals and principles.

    Science.gov (United States)

    Placzek, Mark R; Chung, I-Ming; Macedo, Hugo M; Ismail, Siti; Mortera Blanco, Teresa; Lim, Mayasari; Cha, Jae Min; Fauzi, Iliana; Kang, Yunyi; Yeo, David C L; Ma, Chi Yip Joan; Polak, Julia M; Panoskaltsis, Nicki; Mantalaris, Athanasios

    2009-03-01

    In recent years, the potential of stem cell research for tissue engineering-based therapies and regenerative medicine clinical applications has become well established. In 2006, Chung pioneered the first entire organ transplant using adult stem cells and a scaffold for clinical evaluation. With this a new milestone was achieved, with seven patients with myelomeningocele receiving stem cell-derived bladder transplants resulting in substantial improvements in their quality of life. While a bladder is a relatively simple organ, the breakthrough highlights the incredible benefits that can be gained from the cross-disciplinary nature of tissue engineering and regenerative medicine (TERM) that encompasses stem cell research and stem cell bioprocessing. Unquestionably, the development of bioprocess technologies for the transfer of the current laboratory-based practice of stem cell tissue culture to the clinic as therapeutics necessitates the application of engineering principles and practices to achieve control, reproducibility, automation, validation and safety of the process and the product. The successful translation will require contributions from fundamental research (from developmental biology to the 'omics' technologies and advances in immunology) and from existing industrial practice (biologics), especially on automation, quality assurance and regulation. The timely development, integration and execution of various components will be critical-failures of the past (such as in the commercialization of skin equivalents) on marketing, pricing, production and advertising should not be repeated. This review aims to address the principles required for successful stem cell bioprocessing so that they can be applied deftly to clinical applications. PMID:19033137

  12. Introduction to history taking and principles of sexual health

    OpenAIRE

    Jones, R; Barton, S

    2004-01-01

    Sexual health has a profound influence over an individual's physical and psychological wellbeing. There is an increasing need to develop effective strategies to reduce the incidence of sexually transmitted infections (STIs) globally. Many STIs are asymptomatic and yet, highly infectious. The sequelae of such infections may be catastrophic and hence, an integrated multidisciplinary and preventative approach to the control of STIs is clearly necessary. Sexual history taking holds the key to the...

  13. FROM THE HISTORY OF PHYSICS: Tricentenary of Isaac Newton's "Mathematical Principles of Natural Philosophy"

    Science.gov (United States)

    Ginzburg, Vitalii L.

    1987-01-01

    The first edition of Newton's "Philosophiae Naturalis Principia Mathematica" was published in 1687. The present paper is dedicated to the tricentenary of this event, which is important not just in the history of physics, but of science generally. After the Introduction, the paper continues with the following Sections: Before Newton, Principia, Principia and the method of principles, The nature of gravitation, Critique of Newtonian mechanics and its subsequent development, On Newton, Concluding remarks.

  14. Cell tracking. Principles and applications; Cell Tracking. Prinzipien und Anwendungen

    Energy Technology Data Exchange (ETDEWEB)

    Grimm, Jan [Memorial Sloan Kettering Cancer Center, Dept. of Radiology, New York, NY (United States); Kircher, Moritz F. [Beth Israel Deaconess Medical Center/Harvard Medical School, Dept. of Radiology, Boston, MA (United States); Weissleder, Ralph [Massachusetts General Hospital/ Harvard Medical School, Center for Molecular Imaging Research, Boston, MA (United States)

    2007-01-15

    Cell based therapies such as stem cell therapies or adoptive immunotherapies are currently being explored as a potential treatment for a variety of diseases such as Parkinson's disease, diabetes or cancer. However, quantitative and qualitative evaluation of adoptively transferred cells is indispensable for monitoring the efficiency of the treatment. Current approaches mostly analyze transferred cells from peripheral blood, which cannot assess whether transferred cells actuallyhome to and stay in the targeted tissue. Using cell-labeling methods such as direct labeling or transfection with a marker gene in conjunction with various imaging modalities (MRI, optical or nuclear imaging), labeled cells can be followed in vivo in real-time, and their accumulation as well as function in vivo can be monitored and quantified accurately. This method is usually referred to as ''cell tracking'' or ''cell trafficking'' and is also being applied in basic biological sciences, exemplified in the evaluation of genes contributing to metastasis. This review focuses on principles of this promising methodology and explains various approaches by highlighting recent examples. (orig.) [German] Zellulaere Therapieverfahren wie Stammzelltherapien bei Morbus Parkinson oder Diabetes sowie adoptive Immuntherapien bei Krebs werden in Zukunft zunehmend an Bedeutung gewinnen. Ein Problem bei beiden Therapieverfahren stellt jedoch das qualitative und quantitative Monitoring der Therapie dar. Es ist wichtig zu wissen, ob die applizierten Zellen auch zu ihrem Zielgewebe gelangen und darueber hinaus auch noch funktionsfaehig sind. Diese Informationen sind heute meist nur durch invasive Massnahmen wie Blut- oder Gewebeproben zu erlangen. Das Verfahren des ''Cell Tracking'', bei dem entweder direkt oder ueber Markergene markierte Zellen mit verschiedenen bildgebenden Verfahren (MRT, optische oder nuklearmedizinische Verfahren) in vivo

  15. Fuel cells principles, design, and analysis

    CERN Document Server

    Revankar, Shripad T

    2014-01-01

    ""This book covers all essential themes of fuel cells ranging from fundamentals to applications. It includes key advanced topics important for understanding correctly the underlying multi-science phenomena of fuel cell processes. The book does not only cope with traditional fuel cells but also discusses the future concepts of fuel cells. The book is rich on examples and solutions important for applying the theory into practical use.""-Peter Lund, Aalto University, Helsinki""A good introduction to the range of disciplines needed to design, build and test fuel cells.""-Nigel Brandon, Imperial Co

  16. Separation and sorting of cells in microsystems using physical principles

    Science.gov (United States)

    Lee, Gi-Hun; Kim, Sung-Hwan; Ahn, Kihoon; Lee, Sang-Hoon; Park, Joong Yull

    2016-01-01

    In the last decade, microfabrication techniques have been combined with microfluidics and applied to cell biology. Utilizing such new techniques, various cell studies have been performed for the research of stem cells, immune cells, cancer, neurons, etc. Among the various biological applications of microtechnology-based platforms, cell separation technology has been highly regarded in biological and clinical fields for sorting different types of cells, finding circulating tumor cells (CTCs), and blood cell separation, amongst other things. Many cell separation methods have been created using various physical principles. Representatively, these include hydrodynamic, acoustic, dielectrophoretic, magnetic, optical, and filtering methods. In this review, each of these methods will be introduced, and their physical principles and sample applications described. Each physical principle has its own advantages and disadvantages. The engineers who design the systems and the biologists who use them should understand the pros and cons of each method or principle, to broaden the use of microsystems for cell separation. Continuous development of microsystems for cell separation will lead to new opportunities for diagnosing CTCs and cancer metastasis, as well as other elements in the bloodstream.

  17. Separation and sorting of cells in microsystems using physical principles

    International Nuclear Information System (INIS)

    In the last decade, microfabrication techniques have been combined with microfluidics and applied to cell biology. Utilizing such new techniques, various cell studies have been performed for the research of stem cells, immune cells, cancer, neurons, etc. Among the various biological applications of microtechnology-based platforms, cell separation technology has been highly regarded in biological and clinical fields for sorting different types of cells, finding circulating tumor cells (CTCs), and blood cell separation, amongst other things. Many cell separation methods have been created using various physical principles. Representatively, these include hydrodynamic, acoustic, dielectrophoretic, magnetic, optical, and filtering methods. In this review, each of these methods will be introduced, and their physical principles and sample applications described. Each physical principle has its own advantages and disadvantages. The engineers who design the systems and the biologists who use them should understand the pros and cons of each method or principle, to broaden the use of microsystems for cell separation. Continuous development of microsystems for cell separation will lead to new opportunities for diagnosing CTCs and cancer metastasis, as well as other elements in the bloodstream. (topical review)

  18. Cell-Based Biosensors Principles and Applications

    CERN Document Server

    Wang, Ping

    2009-01-01

    Written by recognized experts the field, this leading-edge resource is the first book to systematically introduce the concept, technology, and development of cell-based biosensors. You find details on the latest cell-based biosensor models and novel micro-structure biosensor techniques. Taking an interdisciplinary approach, this unique volume presents the latest innovative applications of cell-based biosensors in a variety of biomedical fields. The book also explores future trends of cell-based biosensors, including integrated chips, nanotechnology and microfluidics. Over 140 illustrations hel

  19. The principle of self-determination in the family law through history and today

    Directory of Open Access Journals (Sweden)

    Kovaček-Stanić Gordana

    2004-01-01

    Full Text Available In the jubilee year 2004, Serbia marks the 200th anniversary of The First Serbian Uprising, structuring of modern Serbian state and its legal system comparatively speaking, France marks the 200th anniversary of passing the French Civil Code, one of the most significant civil codifications in the 19th century. It was an occasion to study certain institutions of family law through history and today. The used approach is modern, we studied the ways how the principle of self-determination influenced the family-legal solutions today, and we investigated if one could talk about the effect of this principle in the historical sense, too. The principle of self-determination implies the possibility for the subjects of family-legal relations to arrange their own relations themselves – both the partner and parent relations. However, this principle undergoes significant limitations in the family law because the family relations are personal relations by character, as well as because of the need to protect the weaker participant, both the weaker partner or a child who needs protection stemming from his/her very status. Within marriage law, the principle of self-determination of the spouses (extramarital partners is, among other things, made concrete through the possibility for an agreement about the effects of marriage (extramarital union, then through the possibility of agreed divorce, while the procedure of mediation in the marriage litigation contributes to the realization of the mentioned principle. As for the effects of marriage (extramarital union, the paper particularly discusses property relations, that is the marriage property contract, because it is at the moment a current issue in our domestic law. Within the relations between parents and children, the concretization of the principle of self-determination in parental care is significant, particularly in the situations when the relations between the parents were disturbed and resulted in a

  20. Design Principles for Cell Phone Learning in EFL

    Science.gov (United States)

    Wang, Feihong

    2010-01-01

    Cell phone learning (C-learning), as an instructional approach, has been gaining more and more attention in the field of teaching English as a foreign language (EFL) in the last 10 years. While studies have proved C-learning an effective instructional approach in research settings, a review of literature indicates the lack of design principles to…

  1. Polymer electrolyte fuel cells physical principles of materials and operation

    CERN Document Server

    Eikerling, Michael

    2014-01-01

    The book provides a systematic and profound account of scientific challenges in fuel cell research. The introductory chapters bring readers up to date on the urgency and implications of the global energy challenge, the prospects of electrochemical energy conversion technologies, and the thermodynamic and electrochemical principles underlying the operation of polymer electrolyte fuel cells. The book then presents the scientific challenges in fuel cell research as a systematic account of distinct components, length scales, physicochemical processes, and scientific disciplines. The main part of t

  2. The Variable Presentation and Natural History of Langerhans Cell Histiocytosis

    OpenAIRE

    Buckwalter, Joseph A.; Brandser, Eric; Robinson, Robert A.

    1999-01-01

    Langerhans cell histiocytosis is not a well defined or predictable disease. Instead, it is a spectrum of disorders of unknown etiology that vary widely in presentation and natural history, but have in common the proliferation of histiocytic cells and infiltration of these cells into normal tissues. Although the lesions of Langerhans cell histiocytosis consist primarily of histiocytes, eosinophils are a prominent feature in some lesions. Lesions may develop in any tissue, but bone, skin and ly...

  3. Hematopoietic Stem Cell Transplantation and History

    Directory of Open Access Journals (Sweden)

    Atila Tanyeli

    2014-02-01

    Full Text Available Attemps to employ marrow stem cell for therapeutic purpose began in 1940’s. Marrow transplantation might be of use not only in irradiation protection, but also with therapeutic aim to marrow aplasia, leukemia and other diseases. The use and defining tissue antigens in humans were crucial to the improving of transplantation. The administration of methotrexate for GVHD improved the long term survival. Conditioning regimens for myeloablation designed according to diseases. Cord blood and peripheral blood stem cells were used for transplantion after 1980’s. Cord blood and bone marrow stem cell banks established to find HLA matched donor.

  4. The principle of complementarity in the design of reserve networks to conserve biodiversity: a preliminary history

    Indian Academy of Sciences (India)

    James Justus; Sahotra Sarkar

    2002-07-01

    Explicit, quantitative procedures for identifying biodiversity priority areas are replacing the often ad hoc procedures used in the past to design networks of reserves to conserve biodiversity. This change facilitates more informed choices by policy makers, and thereby makes possible greater satisfaction of conservation goals with increased efficiency. A key feature of these procedures is the use of the principle of complementarity, which ensures that areas chosen for inclusion in a reserve network complement those already selected. This paper sketches the historical development of the principle of complementarity and its applications in practical policy decisions. In the first section a brief account is given of the circumstances out of which concerns for more explicit systematic methods for the assessment of the conservation value of different areas arose. The second section details the emergence of the principle of complementarity in four independent contexts. The third section consists of case studies of the use of the principle of complementarity to make practical policy decisions in Australasia, Africa, and America. In the last section, an assessment is made of the extent to which the principle of complementarity transformed the practice of conservation biology by introducing new standards of rigor and explicitness.

  5. Treg Cells, Life History, and Diversity

    OpenAIRE

    Benoist, Christophe; Mathis, Diane

    2012-01-01

    Regulatory T cells expressing the FoxP3 transcription factor have a profound and nonredundant role in several aspects of immunological tolerance. We will review here the specification of this lineage, its population dynamics, and the diversity of subphenotypes that correlate with their diverse roles in controlling inflammation in a variety of settings.

  6. Alkaline polymer electrolyte fuel cells: Principle, challenges, and recent progress

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    Polymer electrolyte membrane fuel cells (PEMFC) have been recognized as a significant power source in future energy systems based on hydrogen. The current PEMFC technology features the employment of acidic polymer electrolytes which, albeit superior to electrolyte solutions, have intrinsically limited the catalysts to noble metals, fundamentally preventing PEMFC from widespread deployment. An effective solution to this problem is to develop fuel cells based on alkaline polymer electrolytes (APEFC), which not only enable the use of non-precious metal catalysts but also avoid the carbonate-precipitate issue which has been troubling the conventional alkaline fuel cells (AFC). This feature article introduces the principle of APEFC, the challenges, and our research progress, and focuses on strategies for developing key materials, including high-performance alkaline polyelectrolytes and stable non-precious metal catalysts. For alkaline polymer electrolytes, high ionic conductivity and satisfactory mechanical property are difficult to be balanced, therefore polymer cross-linking is an ultimate strategy. For non-precious metal catalysts, it is urgent to improve the catalytic activity and stability. New materials, such as transition-metal complexes, nitrogen-doped carbon nanotubes, and metal carbides, would become applicable in APEFC.

  7. Principles of bacterial cell-size determination revealed by cell wall synthesis perturbations

    OpenAIRE

    Carolina Tropini; Timothy K. Lee; Jen Hsin; Samantha M. Desmarais; Tristan Ursell; Russell D. Monds; Kerwyn Casey Huang

    2014-01-01

    Although bacterial cell morphology is tightly controlled, the principles of size regulation remain elusive. In Escherichia coli, perturbation of cell-wall synthesis often results in similar morphologies, making it difficult to deconvolve the complex genotype-phenotype relationships underlying morphogenesis. Here we modulated cell width through heterologous expression of sequences encoding the essential enzyme PBP2 and through sublethal treatments with drugs that inhibit PBP2 and the MreB cyto...

  8. The canonical equation of adaptive dynamics for life histories: from fitness-returns to selection gradients and Pontryagin's maximum principle.

    Science.gov (United States)

    Metz, Johan A Jacob; Staňková, Kateřina; Johansson, Jacob

    2016-03-01

    This paper should be read as addendum to Dieckmann et al. (J Theor Biol 241:370-389, 2006) and Parvinen et al. (J Math Biol 67: 509-533, 2013). Our goal is, using little more than high-school calculus, to (1) exhibit the form of the canonical equation of adaptive dynamics for classical life history problems, where the examples in Dieckmann et al. (J Theor Biol 241:370-389, 2006) and Parvinen et al. (J Math Biol 67: 509-533, 2013) are chosen such that they avoid a number of the problems that one gets in this most relevant of applications, (2) derive the fitness gradient occurring in the CE from simple fitness return arguments, (3) show explicitly that setting said fitness gradient equal to zero results in the classical marginal value principle from evolutionary ecology, (4) show that the latter in turn is equivalent to Pontryagin's maximum principle, a well known equivalence that however in the literature is given either ex cathedra or is proven with more advanced tools, (5) connect the classical optimisation arguments of life history theory a little better to real biology (Mendelian populations with separate sexes subject to an environmental feedback loop), (6) make a minor improvement to the form of the CE for the examples in Dieckmann et al. and Parvinen et al. PMID:26586121

  9. PMAC Principle and Its Application to Cell Winding

    Institute of Scientific and Technical Information of China (English)

    Zhao Xiaolong; Yang yonggang; Zhang Zhiyuan; Wu Fengming

    2004-01-01

    The structure and principle of the PMAC (Programmable Multi-Axis Controller) were described.The implementation of PMAC hardware was illustrated by taking the winding process of one cell for example.The main obvious character of PMAC is to complete a movement program in turns of movement sequence.When PMAC is notified to execute a motion program, it will process one command every time and finish all the calculation to be ready for real action.PMAC card works always prior to real action, when necessary, it can always coordinate correctly with the action which will be carried out soon PMAC will automatically carry out the function of resource management periodically to make sure that the whole system is in correct condition.And also, it can communicate with host computer anytime even during a movement series.The responsibility of PMAC is to organize command according to priority to optimize the system, so as to run the application program safely and efficiently.The function and application of control were emphasized.

  10. DNA Charge Transport: from Chemical Principles to the Cell.

    Science.gov (United States)

    Arnold, Anna R; Grodick, Michael A; Barton, Jacqueline K

    2016-01-21

    The DNA double helix has captured the imagination of many, bringing it to the forefront of biological research. DNA has unique features that extend our interest into areas of chemistry, physics, material science, and engineering. Our laboratory has focused on studies of DNA charge transport (CT), wherein charges can efficiently travel long molecular distances through the DNA helix while maintaining an exquisite sensitivity to base pair π-stacking. Because DNA CT chemistry reports on the integrity of the DNA duplex, this property may be exploited to develop electrochemical devices to detect DNA lesions and DNA-binding proteins. Furthermore, studies now indicate that DNA CT may also be used in the cell by, for example, DNA repair proteins, as a cellular diagnostic, in order to scan the genome to localize efficiently to damage sites. In this review, we describe this evolution of DNA CT chemistry from the discovery of fundamental chemical principles to applications in diagnostic strategies and possible roles in biology. PMID:26933744

  11. Principles, exemplars, and uses of history in early 20th century genetics.

    Science.gov (United States)

    Skopek, Jeffrey M

    2011-06-01

    This paper is concerned with the uses of history in science. It focuses in particular on Anglo-American genetics and on university textbooks--where the canon of a science is consolidated, as the heterogeneous approaches and controversies of its practice are rendered unified for its reproduction. Tracing the emergence and eventual standardization of geneticists' use of a case-based method of teaching in the 1920s-1950s, this paper argues that geneticists created historical environments in their textbooks-spaces in which students developed an understanding of the laws of genetics through simulations of their discovery and use. Witnessing the unfolding of Mendel's and Morgan's experiments and performing genetic crosses on paper, students learned not only the rules that were explicitly taught as such, but also the experientially-based, tacit skills needed to find and follow these rules. This didactic system taught them how to go on when confronting new situations, and in doing so, provided geneticists with an important disciplinary tool, freeing the first steps of their student's enculturation from the physical infrastructure of the laboratory. PMID:21486660

  12. Novel fuel cell with nanocomposite functional layer designed by perovskite solar cell principle

    OpenAIRE

    Zhu, Bin; Huang, Yizhong; Fan, L.; Ma, Y.; Wang, Baoyuan; Xia, Chen; Afzal, Muhammad; Zhang, B.; Dong, W; H. Wang; Lund, P. D.

    2016-01-01

    A novel fuel-to-electricity conversion technology resembling a fuel cell has been developed based on the perovskite solar cell principle using a perovskite, e.g. La0.6Sr0.4Co0.2Fe0.8O3-δ and an ionic nanocomposite material as a core functional layer, sandwiched between n- and p-conducting layers. The conversion process makes use of semiconductor energy bands and junctions properties. The physical properties of the junction and alignment of the semiconductor energy band allow for direct ion tr...

  13. Design principles of cell circuits with paradoxical components

    OpenAIRE

    Hart, Yuval; Yaron E Antebi; Mayo, Avraham E.; Friedman, Nir; Alon, Uri

    2012-01-01

    Biological systems display complex networks of interactions both at the level of molecules inside the cell and at the level of interactions between cells. Networks of interacting molecules, such as transcription networks, have been shown to be composed of recurring circuits called network motifs, each with specific dynamical functions. Much less is known about the possibility of such circuit analysis in networks made of communicating cells. Here, we study models of circuits in which a few cel...

  14. General principles regarding the use of adult stem cells.

    Science.gov (United States)

    de Paula, I Carrasco

    2008-02-01

    With only a few, almost inevitable exceptions, biomedical research has developed within the last 50 years under the tutelage of ethical standards of notable precision. In the vast world of scientific investigation, few disciplines can boast of having realized documents of such ethical rigour, and respect for the integrity and intrinsic value of the human person has been one of the cardinal principles of the researcher. Research is intrinsic to the medical profession; the reward of research is knowledge and its techniques are ordered towards maintenance of human health. Since this end concerns human beings, it demands an extremely rigorous ethical approach. Ethical aspects are present from the first moments of the experimental project and occur on three levels: choice of the objectives, selection and use of the appropriate means for the study, and application of resultant new discoveries. Today, our moral attention cannot be reduced to a cost-benefit analysis. Biomedical sciences and medicine have overlapping areas of interest that can be sources of tension: the good of the subject versus scientific utility; profit versus complexity of research; liberty versus ethical and juridical bonds; the public versus the private; and the individual versus the community. Here, I attempt to formulate some essential principles that should guarantee humane measures for research on humans. PMID:18181949

  15. The RCT Approach for Cell Coverage Prediction ( Ⅰ ) : Principles

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    A new method for the coverage prediction of Cellular Mobile Radio (CMR) system is developed and its basic principle is presented. Unlike the Statistical Prediction Model (SPM) that estimates propagation loss by empirical formulas or the Deterministic Prediction Model (DPM) that reckons propagation loss with analytical expressions, the Radio Computerized Tomography (RCT) method does not seek to express the propagation loss explicitly. The 2-D distribution of propagation loss factor is computed using CT technique,based on measured data collected through drive test under appropriate geometric constraint. The total propagation loss can be obtained by integral of propagation loss factor along the equivalent ray path. The advantages and limitations of the technique, as well as its implementation are discussed.

  16. Branching angles of pyramidal cell dendrites follow common geometrical design principles in different cortical areas

    OpenAIRE

    Concha Bielza; Ruth Benavides-Piccione; Pedro López-Cruz; Pedro Larrañaga; Javier DeFelipe

    2014-01-01

    Unraveling pyramidal cell structure is crucial to understanding cortical circuit computations. Although it is well known that pyramidal cell branching structure differs in the various cortical areas, the principles that determine the geometric shapes of these cells are not fully understood. Here we analyzed and modeled with a von Mises distribution the branching angles in 3D reconstructed basal dendritic arbors of hundreds of intracellularly injected cortical pyramidal cells in seven differen...

  17. Mammalian designer cells: Engineering principles and biomedical applications.

    Science.gov (United States)

    Xie, Mingqi; Fussenegger, Martin

    2015-07-01

    Biotechnology is a widely interdisciplinary field focusing on the use of living cells or organisms to solve established problems in medicine, food production and agriculture. Synthetic biology, the science of engineering complex biological systems that do not exist in nature, continues to provide the biotechnology industry with tools, technologies and intellectual property leading to improved cellular performance. One key aspect of synthetic biology is the engineering of deliberately reprogrammed designer cells whose behavior can be controlled over time and space. This review discusses the most commonly used techniques to engineer mammalian designer cells; while control elements acting on the transcriptional and translational levels of target gene expression determine the kinetic and dynamic profiles, coupling them to a variety of extracellular stimuli permits their remote control with user-defined trigger signals. Designer mammalian cells with novel or improved biological functions not only directly improve the production efficiency during biopharmaceutical manufacturing but also open the door for cell-based treatment strategies in molecular and translational medicine. In the future, the rational combination of multiple sets of designer cells could permit the construction and regulation of higher-order systems with increased complexity, thereby enabling the molecular reprogramming of tissues, organisms or even populations with highest precision. PMID:26010998

  18. Probing mechanical principles of cell-nanomaterial interactions

    Science.gov (United States)

    Gao, Huajian

    2014-01-01

    With the rapid development of nanotechnology, various types of nanoparticles, nanowires, nanofibers, nanotubes, and atomically thin plates and sheets have emerged as candidates for an ever increasing list of potential applications for next generation electronics, microchips, composites, barrier coatings, biosensors, drug delivery, and energy harvesting and conversion systems. There is now an urgent societal need to understand both beneficial and hazardous effects of nanotechnology which is projected to produce and release thousands of tons of nanomaterials into the environment in the coming decades. This paper aims to present an overview of some recent studies conducted at Brown University on the mechanics of cell-nanomaterial interactions, including the modeling of nanoparticles entering cells by receptor-mediated endocytosis and coarse-grained molecular dynamics simulations of nanoparticles interacting with cell membranes. The discussions will be organized around the following questions: Why and how does cellular uptake of nanoparticles depend on particle size, shape, elasticity and surface structure? In particular, we will discuss the effect of nanoparticle size on receptor-mediated endocytosis, the effect of elastic stiffness on cell-particle interactions, how high aspect ratio nanomaterials such as carbon nanotubes and graphenes enter cells and how different geometrical patterns of ligands on a nanoparticle can be designed to control the rate of particle uptake.

  19. Applying the maximum information principle to cell transmission model of tra-ffic flow

    Institute of Scientific and Technical Information of China (English)

    刘喜敏; 卢守峰

    2013-01-01

    This paper integrates the maximum information principle with the Cell Transmission Model (CTM) to formulate the velo-city distribution evolution of vehicle traffic flow. The proposed discrete traffic kinetic model uses the cell transmission model to cal-culate the macroscopic variables of the vehicle transmission, and the maximum information principle to examine the velocity distri-bution in each cell. The velocity distribution based on maximum information principle is solved by the Lagrange multiplier method. The advantage of the proposed model is that it can simultaneously calculate the hydrodynamic variables and velocity distribution at the cell level. An example shows how the proposed model works. The proposed model is a hybrid traffic simulation model, which can be used to understand the self-organization phenomena in traffic flows and predict the traffic evolution.

  20. Major Pesticides Are More Toxic to Human Cells Than Their Declared Active Principles

    OpenAIRE

    Robin Mesnage; Nicolas Defarge; Joël Spiroux de Vendômois; Gilles-Eric Séralini

    2014-01-01

    Pesticides are used throughout the world as mixtures called formulations. They contain adjuvants, which are often kept confidential and are called inerts by the manufacturing companies, plus a declared active principle, which is usually tested alone. We tested the toxicity of 9 pesticides, comparing active principles and their formulations, on three human cell lines (HepG2, HEK293, and JEG3). Glyphosate, isoproturon, fluroxypyr, pirimicarb, imidacloprid, acetamiprid, tebuconazole, epoxiconazo...

  1. Membrane separation principle used for gas drying processes in fuel cells and life support systems

    International Nuclear Information System (INIS)

    Different membrane separation principles as applied to fuel cell powerplants and ECLSS are described. A new separator type that enables smaller weight and geometries and requires less energy than conventional mechanical separator techniques for space applications is presented. Module optimization and investigations concerning ECLSS applications are discussed. 5 refs

  2. Prediction of solid oxide fuel cell cathode activity with first-principles descriptors

    DEFF Research Database (Denmark)

    Lee, Yueh-Lin; Kleis, Jesper; Rossmeisl, Jan;

    2011-01-01

    In this work we demonstrate that the experimentally measured area specific resistance and oxygen surface exchange of solid oxide fuel cell cathode perovskites are strongly correlated with the first-principles calculated oxygen p-band center and vacancy formation energy. These quantities are there...

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

    Directory of Open Access Journals (Sweden)

    Hyunjoo Park

    2013-03-01

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

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

    OpenAIRE

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

    2013-01-01

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

  5. Major Pesticides Are More Toxic to Human Cells Than Their Declared Active Principles

    Directory of Open Access Journals (Sweden)

    Robin Mesnage

    2014-01-01

    Full Text Available Pesticides are used throughout the world as mixtures called formulations. They contain adjuvants, which are often kept confidential and are called inerts by the manufacturing companies, plus a declared active principle, which is usually tested alone. We tested the toxicity of 9 pesticides, comparing active principles and their formulations, on three human cell lines (HepG2, HEK293, and JEG3. Glyphosate, isoproturon, fluroxypyr, pirimicarb, imidacloprid, acetamiprid, tebuconazole, epoxiconazole, and prochloraz constitute, respectively, the active principles of 3 major herbicides, 3 insecticides, and 3 fungicides. We measured mitochondrial activities, membrane degradations, and caspases 3/7 activities. Fungicides were the most toxic from concentrations 300–600 times lower than agricultural dilutions, followed by herbicides and then insecticides, with very similar profiles in all cell types. Despite its relatively benign reputation, Roundup was among the most toxic herbicides and insecticides tested. Most importantly, 8 formulations out of 9 were up to one thousand times more toxic than their active principles. Our results challenge the relevance of the acceptable daily intake for pesticides because this norm is calculated from the toxicity of the active principle alone. Chronic tests on pesticides may not reflect relevant environmental exposures if only one ingredient of these mixtures is tested alone.

  6. Design principle for absorption enhancement with nanoparticles in thin-film silicon solar cells

    International Nuclear Information System (INIS)

    The use of nanoparticles in solar cells has created many controversies. In this paper, different mechanisms of nanoparticles with different materials with diameters varying from 50 to 200 nm, surface coverage at 5, 20, and 60 %, and different locations are analyzed systematically for efficient light trapping in a thin-film c-Si solar cell. Mie theory and the finite difference time domain method are used for analysis to give a design principle with nanoparticles for the solar cell application. Metals exhibit plasmonic resonances and angular scattering, while dielectrics show anti-reflection and scattering in the incident direction. A table is given to summarize the advantages and disadvantages in different conditions. The silicon absorption enhancement with nanoparticles on top is mainly in the shorter wavelengths below 700 nm, and both Al and SiO2 nanoparticles with diameter around 100 nm show the most significant enhancement. The silicon absorption enhancement with embedded nanoparticles takes place in the longer wavelengths over 700 nm, and Ag and SiO2 nanoparticles with larger diameter around 200 nm perform better. However, the light absorbed by Ag nanoparticles will be converted to heat and will lead to decrease in cell efficiency; hence, the choice of metallic nanoparticles in applications to solar cells should be carefully considered. The design principle proposed in this work gives a guideline by choosing reasonable parameters for the different requirements in the application of thin-film solar cells

  7. Approaches of elementary school students towards the lesson of Ataturk’s principles and history of Turkish Revolution of the Turkish Republic

    Directory of Open Access Journals (Sweden)

    Bengül Salman Bolat

    2013-04-01

    Full Text Available It can be said that French Revolution, broke out in 1789, affected Europe deeply in freedom, equality, particularly with the ideas of nationalism. New values were introduced with the nationalism. With the new symbols, national states sought to give the community a new identity. Within this new formation, political powers in the adoption by the community and in its efforts to provide legitimacy, transfer tools to future generations are extremely important. In this context, the teaching of history is of great importance. In this study, a field survey was conducted on the lesson called Atatürk’s Principles and History of Revolution which have aims such as being able to teach the stages of foundation of the Republic of Turkey and to transfer the information to future generations. In that study, it was also aimed to find out information about the methodology of the lesson which has great importance on the development of the consciousness of Nationalism and citizenship and about founder of Turkish republic Ataturk. In this study a survey model was used. The students, who were studying in Kırşehir in the 2010-2011 academic years, set the population of the survey. To collect data in the survey, a questioner is used with the aim of discovering the opinions of the students about the course of “Atatürk’s Principles and History of Revolution. In the analysis, the t-test is used and the method of single factor variance analysis (ANOVA and percentage frequency is used.

  8. Impact of sub-cell internal luminescence yields on energy conversion efficiencies of tandem solar cells: A design principle

    International Nuclear Information System (INIS)

    To develop a realistic design principle, we calculated the maximum conversion efficiency ηsc and optimized sub-cell band-gap energies Eg in double-junction tandem solar cells via a detailed-balance theory, paying particular attention to their dependence on internal luminescence quantum yields yint of the top and bottom sub-cell materials. A strong drop in the maximum ηsc occurs when yint slightly drops from 1 to 0.9, where the drop in yint of the bottom cell causes a stronger effect than that of the top cell. For low values of yint, the maximum ηsc has a simple logarithmic dependence on the geometric mean of the two sub-cells'yint

  9. A brief history of the Japan Society for Cell Biology.

    Science.gov (United States)

    Tashiro, Y; Okigaki, T

    2001-02-01

    The Japan Society for Cell Biology (JSCB) was first founded in 1950 as the Japan Society for Cellular Chemistry under the vigorous leadership of Seizo Katsunuma, in collaboration with Shigeyasu Amano and Satimaru Seno. The Society was provisionally named as above simply because cell biology had not yet been coined at that time in Japan, although in prospect and reality the Society was in fact for the purpose of pursuing cell biology. Later in 1964, the Society was properly renamed as the Japan Society for Cell Biology. After this renaming, the JSCB made great efforts to adapt itself to the rapid progress being made in cell biology. For this purpose the Society's constitution was created in 1966 and revised in 1969. According to the revised constitution, the President, Executive Committee and Councils were to be determined by ballot vote. The style of the annual meetings was gradually modified to incorporate general oral and poster presentations in addition to Symposia (1969-1974). The publication of annual periodicals in Japanese called Symposia of the Japan Society for Cellular Chemistry (1951-1967) and later Symposia of the Japan Society for Cell Biology (1968-1974) was replaced by a new international journal called Cell Structure and Function initiated in 1975. This reformation made it possible for the Society to participate in the Science Council of Japan in 1975 and finally in 1993 to acquire its own study section of Cell Biology with grants-in-aid from the Ministry of Education and Science, Japan. The JSCB hosted the 3rd International Congress on Cell Biology (ICCB) in 1984 and the 3rd Asian-Pacific Organization for Cell Biology (APOCB) Congress in 1998, thus contributing to the international advancement of cell biology. Now the membership of JSCB stands at approximately 1,800 and the number of presentations per meeting is 300 to 400 annually. Although a good number of interesting and important findings in cell biology have been reported from Japan, the

  10. Design principles for high efficiency small-grain polysilicon solar cells, with supporting experimental studies

    Science.gov (United States)

    Lindholm, F. A.; Neugroschel, A.; Sah, C. T.

    1982-01-01

    Design principles suggested here aim toward high conversion efficiency (greater than 15 percent) in polysilicon cells. The principles seek to decrease the liabilities of both intragranular and grain-boundary-surface defects. The advantages of a phosphorus atom concentration gradient in a thin (less than 50 microns) base of a p(+)/n(x)/n(+) drift-field solar cell, which produces favorable gradients in chemical potential, minority-carrier mobility and diffusivity, and recombination lifetime (via phosphorus gettering) are suggested. The degrading effects of grain boundaries are reduced by these three gradients and by substituting atoms (P, H, F or Li) for vacancies on the grain-boundary surface. From recent experiments comes support for the benefits of P diffusion down grain boundaries and, for quasi-grain-boundary-free and related structures. New analytic solutions for the n(x)-base include the effect of a power-law dependence between P concentration and lifetime. These provide an upper-bound estimate on the open circuit voltage. Finite-difference numerical solutions of the six Shockley equations furnish complete information about all solar-cell parameters and add insight concerning design.

  11. F-cell world drive 2011: are tactical medicine principles applicable to a civilian scenario?

    Science.gov (United States)

    Burkert, Manuel G

    2012-01-01

    In 2011, a Mercedes Benz (MB) conducted the F-Cell World Drive tour around the globe in 125 days. While crossing Asia from Shanghai (China) to Helsinki (Finland) by car, en route medical care was provided by embedded emergency physicians. The designated route crossed four different countries, multiple climate zones, and challenging road conditions. There was only limited information provided about hospitals and emergency medical services within different host nations in the planning phase, so we adopted tactical medical principles for mission planning and execution, as we were facing remote conditions and limitations to equipment, staffing, and patient transport. PMID:22427051

  12. Operating principles of Notch-Delta-Jagged module of cell-cell communication

    Science.gov (United States)

    Jolly, Mohit Kumar; Boareto, Marcelo; Lu, Mingyang; Onuchic, Jose' N.; Clementi, Cecilia; Ben-Jacob, Eshel

    2015-05-01

    Notch pathway is an evolutionarily conserved cell-cell communication mechanism governing cell-fate during development and tumor progression. It is activated when Notch receptor of one cell binds to either of its ligand—Delta or Jagged—of another cell. Notch-Delta (ND) signaling forms a two-way switch, and two cells interacting via ND signaling adopt different fates—Sender (high ligand, low receptor) and Receiver (low ligand, high receptor). Notch-Delta-Jagged signaling (NDJ) behaves as a three-way switch and enables an additional fate—hybrid Sender/Receiver (S/R) (medium ligand, medium receptor). Here, by extending our framework of NDJ signaling for a two-cell system, we show that higher production rate of Jagged, but not that of Delta, expands the range of parameters for which both cells attain the hybrid S/R state. Conversely, glycosyltransferase Fringe and cis-inhibition reduces this range of conditions, and reduces the relative stability of the hybrid S/R state, thereby promoting cell-fate divergence and consequently lateral inhibition-based patterns. Lastly, soluble Jagged drives the cells to attain the hybrid S/R state, and soluble Delta drives them to be Receivers. We also discuss the critical role of hybrid S/R state in promoting cancer metastasis by enabling collective cell migration and expanding cancer stem cell (CSC) population.

  13. Genetic instability persists in non-neoplastic urothelial cells from patients with a history of urothelial cell carcinoma.

    Science.gov (United States)

    de Castro Marcondes, João Paulo; de Oliveira, Maria Luiza Cotrim Sartor; Gontijo, Alisson M; de Camargo, João Lauro Viana; Salvadori, Daisy Maria Fávero

    2014-01-01

    Bladder cancer is one of the most common genitourinary neoplasms in industrialized countries. Multifocality and high recurrence rates are prominent clinical features of this disease and contribute to its high morbidity. Therefore, more sensitive and less invasive techniques could help identify individuals with asymptomatic disease. In this context, we used the micronucleus assay to evaluate whether cytogenetic alterations could be used as biomarkers for monitoring patients with a history of urothelial cell carcinoma (UCC). We determined the frequency of micronucleated urothelial cells (MNC) in exfoliated bladder cells from 105 patients with (n = 52) or without (n = 53) a history of UCC, all of whom tested negative for neoplasia by cytopathological and histopathological analyses. MNC frequencies were increased in patients with a history of UCC (non-smoker and smoker/ex-smoker patients vs non-smoker and smoker/ex-smoker controls; pMNC frequency compared to patients with non-recurrent neoplasia. However, logistic regression using smoking habits, age and gender as confounding factors did not confirm MNC frequency as a marker for UCC recurrence. Fluorescent in situ hybridization analysis (using a pan-centromeric probe) showed that micronuclei (MN) arose mainly from clastogenic events regardless of UCC and/or smoking histories. In conclusion, our results confirm previous indications that subjects with a history of UCC harbor genetically unstable cells in the bladder urothelium. Furthermore, these results support using the micronucleus assay as an important tool for monitoring patients with a history of UCC and tumor recurrence. PMID:24465937

  14. Using fetal cells for prenatal diagnosis: History and recent progress.

    Science.gov (United States)

    Beaudet, Arthur L

    2016-06-01

    The potential to use fetal cells in the mother's circulation during the first or second trimester for prenatal diagnosis was described in 1968, but it has not been possible do develop a routine clinical prenatal test despite extensive commercial and academic research efforts. Early attention focused on the detection of aneuploidy, but more recent technology opens the possibility of high resolution detection of copy number abnormalities and even whole genome or exome sequencing to detect both inherited and de novo mutations. In the interim, cell-free noninvasive prenatal testing NIPT has allowed improved detection of aneuploidy, but this has led to a sharp reduction in the number of amniocentesis and chorionic villus sampling (CVS) procedures, which inevitably implies reduced detection of serious de novo deletion abnormalities. Attention has focused of both fetal nucleated red blood cells (fnRBCs) and trophoblasts. Recent progress presented at meetings, but not yet published, suggests that it will soon be possible to perform genome-wide relatively high resolution detection of deletions and duplications by recovering fetal trophoblasts during the first trimester and analyzing them by whole gene genome amplification followed by copy number analysis using arrays or next generation sequencing. © 2016 Wiley Periodicals, Inc. PMID:27133782

  15. History of Neural Stem Cell Research and Its Clinical Application.

    Science.gov (United States)

    Takagi, Yasushi

    2016-03-15

    "Once development was ended…in the adult centers, the nerve paths are something fixed and immutable. Everything may die, nothing may be regenerated," wrote Santiago Ramón y Cajal, a Spanish neuroanatomist and Nobel Prize winner and the father of modern neuroscience. This statement was the central dogma in neuroscience for a long time. However, in the 1960s, neural stem cells (NSCs) were discovered. Since then, our knowledge about NSCs has continued to grow. This review focuses on our current knowledge about NSCs and their surrounding microenvironment. In addition, the clinical application of NSCs for the treatment of various central nervous system diseases is also summarized. PMID:26888043

  16. Mechanical principle of enhancing cell-substrate adhesion via pre-tension in the cytoskeleton.

    Science.gov (United States)

    Chen, Bin; Gao, Huajian

    2010-05-19

    Motivated by our earlier study on the effect of pre-tension in gecko adhesion, here we investigate whether and how pre-tension in cytoskeleton influences cell adhesion by developing a stochastic-elasticity model of a stress fiber attached on a rigid substrate via molecular bonds. By comparing the variations in adhesion lifetime and observing the sequences of bond breaking with and without pre-tension in the stress fiber under the same applied force, we demonstrate that the effect of pre-tension is to shift the interfacial failure mode from cracklike propagation toward uniform bond failure within the contact region, thereby greatly increasing the adhesion lifetime. Since stress fibers are the primary load-bearing components of cells, as well as the basic functional units of cytoskeleton that facilitate cell adhesion, this study suggests a feasible mechanism by which cell adhesion could be actively controlled via cytoskeletal contractility and proposes that pre-tension may be a general principle in biological adhesion. PMID:20483323

  17. First Principles based thermo-kinetic modeling of electrocatalytic processes at fuel cell cathodes

    Science.gov (United States)

    Gadre, Milind Jayram

    Fuel Cells are promising alternative-energy technologies for the future. The design of efficient, cost-effective materials to catalyze the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is a major hurdle facing the large-scale commercialization of these technologies. Perovskites of transition metal oxides and related hetero-structures are promising, cheap materials for oxygen electro-catalysis. Understanding the detailed nature of OER and ORR catalytic activity of various surfaces of perovskite oxides can help design highly active perovskite cathodes. My research work involves first principles based thermo-kinetic modeling of various oxygen electro-catalytic processes on the surfaces of transition metal perovskites, to develop detailed mechanistic understanding of oxygen reduction/evolution reactions, and to suggest ways to engineer better cathode materials.

  18. Generation of subgroup weights employing shielded cross section conservation principle for representative pin cells

    International Nuclear Information System (INIS)

    A new method for generating subgroup weights, which are required for the subgroup method based resonance calculation, is formulated by imposing the shielded cross section conservation principle, rather than the resonance integral conservation. The inconsistency of the background cross sections defined in the subgroup parameter generation and usage steps is first identified and the impact of this inconsistency is quantified. To remove this inconsistency which leads to a large error that would require nontrivial empirical adjustments of the resonance data, a consistent procedure employing subgroup level dependent background cross sections to conserve the shielded cross sections for a few number representative pin cells is derived. This procedure requires the solution of a constrained minimization problem for which a regularization technique is used to exclude ill-conditioned calculations. Results indicate that this procedure can improve significantly the accuracy of resonance treatment in codes involving enforced equivalence after the solution of the subgroup fixed source problem, such as DeCART. (authors)

  19. Development and characterization of a cell culture manufacturing process using quality by design (QbD) principles.

    Science.gov (United States)

    Marasco, Daniel M; Gao, Jinxin; Griffiths, Kristi; Froggatt, Christopher; Wang, Tongtong; Wei, Gan

    2014-01-01

    The principles of quality by design (QbD) have been applied in cell culture manufacturing process development and characterization in the biotech industry. Here we share our approach and practice in developing and characterizing a cell culture manufacturing process using QbD principles for establishing a process control strategy. Process development and characterization start with critical quality attribute identification, followed by process parameter and incoming raw material risk assessment, design of experiment, and process parameter classification, and conclude with a design space construction. Finally, a rational process control strategy is established and documented. PMID:23828505

  20. History of the Department of Cell Biology at Yale School of Medicine, 1813-2010

    OpenAIRE

    Lentz, Thomas L.

    2011-01-01

    The Department of Cell Biology at the Yale University School of Medicine was established in 1983. It was preceded by the Section of Cell Biology, which was formed in 1973 when George E. Palade and collaborators came to Yale from the Rockefeller University. Cell Biology at Yale had its origins in the Department of Anatomy that existed from the beginning of classes at the Medical Institution of Yale College in 1813. This article reviews the history of the Department of Anatomy at Yale and its e...

  1. THE HISTORY OF BUILDING THE NORTHERN FRATERNAL CELLS OF VIRGIN MARY ASSUMPTION MONASTERY IN TIKHVIN

    Directory of Open Access Journals (Sweden)

    Tatiana Nikolaevna PYATNITSKAYA

    2014-01-01

    Full Text Available The article is focused on the formation of one of the fra-ternal houses of the Virgin Mary Assumption Monastery in Tikhvin (Leningrad region, the volume-spatial compo-sition of which was developed during the second half of the 17th century. It describes the history of the complex origin around the Assumption Cathedral of the 16th cen-tury and Cell housing location in the wooden and stone ensembles. Comparing the archival documents and the data obtained as a result of field studies, were identified the initial planning and design features of the Nordic fraternal cells. The research identified brigades of Tikhvin masons of 1680-1690 who worked in the construction of the building. Fragments of the original architectural dec-orations and facade colors were found. The research also identified graphic reconstructions, giving an idea not only of the original appearance of the building, but also the history of its changes.

  2. The natural history of adult pulmonary Langerhans cell histiocytosis: a prospective multicentre study

    OpenAIRE

    Tazi, Abdellatif; de Margerie, Constance; Naccache, Jean Marc; Fry, Stéphanie; Dominique, Stéphane; Jouneau, Stéphane; Lorillon, Gwenaël; Bugnet, Emmanuelle; Chiron, Raphael; Wallaert, Benoit; Valeyre, Dominique; Chevret, Sylvie

    2015-01-01

    Background The natural history of pulmonary Langerhans cell histiocytosis (PLCH) has been unclear due to the absence of prospective studies. The rate of patients who experience an early progression of their disease is unknown. Additionally, conflicting effects of smoking cessation on the outcome of PLCH have been reported. Methods In this prospective, multicentre study, 58 consecutive patients with newly diagnosed PLCH were comprehensively evaluated over a two-year period. Our objectives were...

  3. The early history of odontogenic ghost cell lesions: from Thoma to Gorlin.

    Science.gov (United States)

    Ide, Fumio; Kikuchi, Kentaro; Miyazaki, Yuji; Kusama, Kaoru; Saito, Ichiro; Muramatsu, Takashi

    2015-03-01

    To reappraise the early history of odontogenic ghost cell lesions (OGCL), the extensive world literature published from 1838 to 1962 was reviewed. In light of the long history of OGCL, the term "calcifying epithelioma of Malherbe" first appeared in a 1931 French report, and the term "ghost cells" had its origin in two American seminal articles by Thoma and Goldman in 1946. Although Gorlin et al. coined the term "calcifying odontogenic cyst" (COC) in 1962, this type of cyst was initially reported three decades earlier by Rywkind in Russia, and almost concurrently by Blood good in the United States and Sato in Japan. In 1948, Willis provided the initial histological evidence of a peripheral COC in his British pathology textbook. Credit for the earliest clinical presentation of odontoma associated calcifying cystic odontogenic tumor belongs to the American radiology textbook by Thoma in 1917. A Scandinavian journal report published in 1953 by Husted and Pindborg was the first to address a dentinogenic ghost cell tumor, and its peripheral counterpart was originally reported in the Swiss literature 7 years later. The current concept of COC was undoubtedly established by Gorlin et al. but the history of OGCL really started with Thoma's pioneering work about a century ago. PMID:24972654

  4. 钙钛矿太阳能电池的发展与工作原理%Perovskite solar cells:development and working principle

    Institute of Scientific and Technical Information of China (English)

    王琛

    2016-01-01

    Development history of perovskite solar cells is briefly reviewed.Perovskite solarcells are solid-statedye-sensitized solar cells.Describes the structure ofperovskite.Describing the structure and working principle of perovskite solar cells.The energy conversion ef-ficiency of perovskite solar cells has exceeded the amorphous silicon solar cells.latter.A conclusion is drawn that perovskite-based solar cells are expected becoming the next generation thin-film solar cells.The bottleneck of marketization for perovskite-based solar cells is the fabrication of expensive hole transportation layer.The researches aim to resolve it are summarized.%简要回顾了钙钛矿太阳能电池的发展历史,说明了钙钛矿太阳能电池属于染料敏化太阳能电池的一种。介绍了钙钛矿晶体的结构。分层次解释了钙钛矿太阳能电池的结构及工作原理。钙钛矿太阳能电池的光电转换效率已经超过了晶体硅太阳能电池。在未来的发展中,钙钛矿太阳能电池很有可能成为下一代薄膜太阳能电池。指出了钙钛矿太阳能电池由于空穴传输层的材料造价昂贵等缺点导致其无法大规模生产,并简单介绍了解决缺点的最新研究工作。

  5. Neoplastic lesions of endocrine cells in the gastrointestinal tract: ten evolving principles as a basis for clinical understanding

    Directory of Open Access Journals (Sweden)

    Lawrence B

    2012-12-01

    Full Text Available Ben Lawrence,1,2 Malcolm Anderson,3 Simon Schimmack,1 Michael Findlay,2,3 Mark Kidd,1 Irvin Modlin11Department of Surgery, Yale University School of Medicine, New Haven, CT, USA; 2School of Medical Sciences, Faculty of Medical and Health Sciences, University of Auckland, 3Department of Oncology, Auckland District Health Board, Auckland, New ZealandAbstract: Timely and appropriate diagnosis and treatment of patients with gastroenteropancreatic neuroendocrine neoplasms is a difficult clinical endeavor. The field is particularly dynamic, not only in terms of expanding therapeutic options, but in the classifications and biological principles that underpin good decision-making. Acknowledging the confusion created by past changes and the inevitability of future development, we combine our clinical experience with a review of the literature to frame the current understanding of gastroenteropancreatic neuroendocrine neoplasms in terms of a set of principles that have stabilized in the midst of this change. Firstly, we present five principles that guide classification of neuroendocrine neoplasms; specifically principles of prognostic classification, mechanisms of tumorigenesis, undiagnosed disease burden, clues regarding genetic etiology, and typical clinical presentation. Secondly, we offer five clinical principles upon which to build a therapeutic strategy. Specifically, these treatment principles include the separation of options by tumor cell differentiation, and the site of the primary lesion in well differentiated tumors. Chromogranin A is a moderately useful biomarker. Treatment should only be considered by clinicians in a multidisciplinary team, and in the face of multiple potential therapeutic options without a supporting evidence base, clinical trial enrolment remains imperative. Therefore, we provide a current synopsis of classification of gastroenteropancreatic neuroendocrine neoplasms, and their etiology, clinical presentation, and

  6. Cell wall elasticity: I. A critique of the bulk elastic modulus approach and an analysis using polymer elastic principles

    Science.gov (United States)

    Wu, H. I.; Spence, R. D.; Sharpe, P. J.; Goeschl, J. D.

    1985-01-01

    The traditional bulk elastic modulus approach to plant cell pressure-volume relations is inconsistent with its definition. The relationship between the bulk modulus and Young's modulus that forms the basis of their usual application to cell pressure-volume properties is demonstrated to be physically meaningless. The bulk modulus describes stress/strain relations of solid, homogeneous bodies undergoing small deformations, whereas the plant cell is best described as a thin-shelled, fluid-filled structure with a polymer base. Because cell walls possess a polymer structure, an alternative method of mechanical analysis is presented using polymer elasticity principles. This initial study presents the groundwork of polymer mechanics as would be applied to cell walls and discusses how the matrix and microfibrillar network induce nonlinear stress/strain relationships in the cell wall in response to turgor pressure. In subsequent studies, these concepts will be expanded to include anisotropic expansion as regulated by the microfibrillar network.

  7. Using the History of Research on Sickle Cell Anemia to Affect Preservice Teachers' Conceptions of the Nature of Science.

    Science.gov (United States)

    Howe, Eric M.

    This paper examines how using a series of lessons developed from the history of research on sickle cell anemia affects preservice teacher conceptions of the nature of science (NOS). The importance of a pedagogy that has students do science through an integral use of the history of science is effective at enriching students' NOS views is presented.…

  8. Addressing Nature of Science Core Tenets with the History of Science: An Example with Sickle-Cell Anemia & Malaria

    Science.gov (United States)

    Howe, Erica M.

    2007-01-01

    The history of science (HOS) has proven to be a useful pedagogical tool to help students learn about what has come to be regarded as an agreed upon set of core nature of science (NOS) tenets. The following article illustrates an example of how teachers can instrumentally use the history of research on heterozygote protection in sickle-cell anemia…

  9. A middle-aged man with a history of renal cell carcinoma

    Directory of Open Access Journals (Sweden)

    Garciaorr R

    2011-06-01

    Full Text Available A 56 year old man was seen with a lung nodule. He had an extensive past medical history including renal cell carcinoma, congestive heart failure, obstructive sleep apnea and a 135 pack-year history of smoking. His physical examination was consistent with congestive heart failure. Sputum cultures for bacteria, fungi and tuberculosis were all negative. A CT scan revealed a spiculated, noncalcified 2.1 mass in the right lower lobe. PET scan showed the lesion to have a standard uptake value of 1.5. The lesion was followed and after 3 months had enlarged to 6.4 cm. Biopsy was done and consistent with a lung abscess. Conservative therapy resulted in resolution only to have the lesion recur 22 months later with the patient expiring from massive hemoptysis and respiratory failure. This case illustrates the usefulness of doubling time in separating benign from malignant lung lesions.

  10. Current and future regenerative medicine - principles, concepts, and therapeutic use of stem cell therapy and tissue engineering in equine medicine

    DEFF Research Database (Denmark)

    Koch, Thomas Gadegaard; Berg, Lise Charlotte; Betts, Dean H.

    2009-01-01

    be recorded and reported.Stem cell and tissue engineering research in the horse has exciting comparative and equine specific perspectives that most likely will benefit the health of horses and humans. Controlled, well-designed studies are needed to move this new equine research field forward.......This paper provides a bird's-eye perspective of the general principles of stem-cell therapy and tissue engineering; it relates comparative knowledge in this area to the current and future status of equine regenerative medicine.The understanding of equine stem cell biology, biofactors, and scaffolds......, and their potential therapeutic use in horses are rudimentary at present. Mesenchymal stem cell isolation has been proclaimed from several equine tissues in the past few years. Based on the criteria of the International Society for Cellular Therapy, most of these cells are more correctly referred to as multipotent...

  11. History-dependent excitability as a single-cell substrate of transient memory for information discrimination.

    Directory of Open Access Journals (Sweden)

    Fabiano Baroni

    Full Text Available Neurons react differently to incoming stimuli depending upon their previous history of stimulation. This property can be considered as a single-cell substrate for transient memory, or context-dependent information processing: depending upon the current context that the neuron "sees" through the subset of the network impinging on it in the immediate past, the same synaptic event can evoke a postsynaptic spike or just a subthreshold depolarization. We propose a formal definition of History-Dependent Excitability (HDE as a measure of the propensity to firing in any moment in time, linking the subthreshold history-dependent dynamics with spike generation. This definition allows the quantitative assessment of the intrinsic memory for different single-neuron dynamics and input statistics. We illustrate the concept of HDE by considering two general dynamical mechanisms: the passive behavior of an Integrate and Fire (IF neuron, and the inductive behavior of a Generalized Integrate and Fire (GIF neuron with subthreshold damped oscillations. This framework allows us to characterize the sensitivity of different model neurons to the detailed temporal structure of incoming stimuli. While a neuron with intrinsic oscillations discriminates equally well between input trains with the same or different frequency, a passive neuron discriminates better between inputs with different frequencies. This suggests that passive neurons are better suited to rate-based computation, while neurons with subthreshold oscillations are advantageous in a temporal coding scheme. We also address the influence of intrinsic properties in single-cell processing as a function of input statistics, and show that intrinsic oscillations enhance discrimination sensitivity at high input rates. Finally, we discuss how the recognition of these cell-specific discrimination properties might further our understanding of neuronal network computations and their relationships to the distribution and

  12. Alteration of T cell function in healthy persons with a history of thymic x irradiation

    International Nuclear Information System (INIS)

    The possible late effects of x irradiation to the infantile thymus were investigated by studying immune functions in 12 healthy persons with a history of thymic x irradiation and healthy control subjects. No differences were found in serum immunoglobulin values, humoral antibody levels, lymphocyte counts, and lymphocyte reactivity to phytohemagglutinin, vaccinia virus, purified protein derivative (PPD), and allogeneic cells. The irradiation group exhibited cellular hyperresponsiveness to streptokinase-streptodornase (SK-SD). In contrast, mean skin and in vitro lymphocyte responses to Candida albicans were depressed in the patients with thymic irradiation. A dissociation of these two Candida responses was found in only 1 of 14 healthy control subjects but in 7 of 12 irradiated individuals. While thymic irradiation did not result in impaired immunologic defenses leading to clinical disease, it caused alterations in T cell responses similar to those reported in patients with chronic mucocutaneous candidiasis

  13. Alteration of T cell function in healthy persons with a history of thymic x irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Rieger, C.H.L.; Kraft, S.C.; Rothberg, R.M.

    1975-10-01

    The possible late effects of x irradiation to the infantile thymus were investigated by studying immune functions in 12 healthy persons with a history of thymic x irradiation and healthy control subjects. No differences were found in serum immunoglobulin values, humoral antibody levels, lymphocyte counts, and lymphocyte reactivity to phytohemagglutinin, vaccinia virus, purified protein derivative (PPD), and allogeneic cells. The irradiation group exhibited cellular hyperresponsiveness to streptokinase-streptodornase (SK-SD). In contrast, mean skin and in vitro lymphocyte responses to Candida albicans were depressed in the patients with thymic irradiation. A dissociation of these two Candida responses was found in only 1 of 14 healthy control subjects but in 7 of 12 irradiated individuals. While thymic irradiation did not result in impaired immunologic defenses leading to clinical disease, it caused alterations in T cell responses similar to those reported in patients with chronic mucocutaneous candidiasis.

  14. Further insights into the natural history and management of primary cutaneous neuroendocrine (merkel cell) carcinoma

    International Nuclear Information System (INIS)

    Purpose: Primary cutaneous neuroendocrine (Merkel cell) carcinoma is a rare neoplasm with aggressive behavior but potential for response to radiotherapy and chemotherapy. Optimal treatment regimens are evolving based on reports of case series and a growing understanding of the natural history. Methods and Materials: A retrospective analysis of 34 cases treated at two Australian Institutions over 13 years is presented, focusing on clinical features and response to therapy. Results: The aggressive nature of this neoplasm is confirmed by the local recurrence rate of 22% following surgical excision, the development of regional node metastases in 76%, and of distant metastases in 70%. Overall median survival was 24 months with 65% of patients succumbing to metastatic disease. An association with B cell malignancies and immunosuppressive therapy is noted, with these patients having a poorer outcome, and one spontaneous remission was observed. Radiation therapy produced responses in 21 of 30 measurable sites (11 complete, 10 partial), and in 11 sites irradiated prophylactically there was only one infield relapse (9%). Responses to chemotherapy were observed in 8 of 20 applications (40%), particularly carboplatin and etoposide given in the setting of regional node disease. Conclusion: In this poor prognosis tumor, further investigation of adjuvant radiotherapy and chemotherapy is warranted, as responsiveness of recurrent disease is confirmed. Immunological factors appear important in the natural history, and their manipulation may offer additional therapeutic options

  15. Current and future regenerative medicine — Principles, concepts, and therapeutic use of stem cell therapy and tissue engineering in equine medicine

    OpenAIRE

    Thomas G. Koch; Berg, Lise C.; Dean H Betts

    2009-01-01

    This paper provides a bird’s-eye perspective of the general principles of stem-cell therapy and tissue engineering; it relates comparative knowledge in this area to the current and future status of equine regenerative medicine.

  16. Clinicopathological Characteristics and Prognosis of Non-Small Cell Lung Cancer Patients Associated with a Family History of Lung Cancer

    OpenAIRE

    Shuji Haraguchi, Kiyoshi Koizumi, Iwao Mikami, Okamoto Junichi, Yoshihito Iijima, Takayuki Ibi, Kazuo Shimizu

    2012-01-01

    Introduction: Clinicopathological characteristics and prognosis of non-small cell lung cancer (NSCLC) patients with a family history of lung cancer (FHLC) have not been well established.Methods: Clinical records of patients with NSCLC treated at our institute from 1982 to 2010 were reviewed with special reference to family history of lung cancer and clinicopathological factors including patient's outcome. Univariate analyses of the factors between the groups of FHLC and non-FHLC were performe...

  17. Clinicopathological Characteristics and Prognosis of Non-Small Cell Lung Cancer Patients Associated with a Family History of Lung Cancer

    OpenAIRE

    Haraguchi, Shuji; Koizumi, Kiyoshi; Mikami, Iwao; Junichi, Okamoto; Iijima, Yoshihito; Ibi, Takayuki; Shimizu, Kazuo

    2011-01-01

    Introduction: Clinicopathological characteristics and prognosis of non-small cell lung cancer (NSCLC) patients with a family history of lung cancer (FHLC) have not been well established. Methods: Clinical records of patients with NSCLC treated at our institute from 1982 to 2010 were reviewed with special reference to family history of lung cancer and clinicopathological factors including patient's outcome. Univariate analyses of the factors between the groups of FHLC and non-FHLC were perform...

  18. Sn doped CdTe as candidate for intermediate-band solar cells: A first principles DFT+GW study

    Science.gov (United States)

    Flores, Mauricio A.; Menéndez-Proupin, Eduardo

    2016-05-01

    In this work, we investigate the electronic properties and defect formation energies of Sn doped CdTe combining first principles density-functional theory and many body GW calculations. Due to the Sn dopant, an isolated impurity band is formed in the middle of the forbidden band gap of CdTe allowing the absorption of sub-bandgap photons via an intermediate-band. Our results suggest CdTe:Sn as a promising candidate for the development of third-generation intermediate-band solar cells with theoretical efficiencies up to 63.2%.

  19. On-line and real-time diagnosis method for proton membrane fuel cell (PEMFC) stack by the superposition principle

    Science.gov (United States)

    Lee, Young-Hyun; Kim, Jonghyeon; Yoo, Seungyeol

    2016-09-01

    The critical cell voltage drop in a stack can be followed by stack defect. A method of detecting defective cell is the cell voltage monitoring. The other methods are based on the nonlinear frequency response. In this paper, the superposition principle for the diagnosis of PEMFC stack is introduced. If critical cell voltage drops exist, the stack behaves as a nonlinear system. This nonlinearity can explicitly appear in the ohmic overpotential region of a voltage-current curve. To detect the critical cell voltage drop, a stack is excited by two input direct test-currents which have smaller amplitude than an operating stack current and have an equal distance value from the operating current. If the difference between one voltage excited by a test current and the voltage excited by a load current is not equal to the difference between the other voltage response and the voltage excited by the load current, the stack system acts as a nonlinear system. This means that there is a critical cell voltage drop. The deviation from the value zero of the difference reflects the grade of the system nonlinearity. A simulation model for the stack diagnosis is developed based on the SPP, and experimentally validated.

  20. Principles of solar cells, LEDs and diodes the role of the PN junction

    CERN Document Server

    Kitai, Adrian

    2011-01-01

    The book will cover the two most important applications of semiconductor diodes - solar cells and LEDs - together with quantitative coverage of the physics of the PN junction at the senior undergraduate level. It will include: Review of semiconductor physicsIntroduction to PN diodesThe solar cellPhysics of efficient conversion of sunlight into electrical energySemiconductor solar cell materials and device physicsAdvanced solar cell materials and devicesThe light emitting diodePhysics of efficient conversion of electrical energy into lightSemiconductor li

  1. Plant cell walls throughout evolution: towards a molecular understanding of their design principles

    Energy Technology Data Exchange (ETDEWEB)

    Sarkar, Purbasha; Bosneaga, Elena; Auer, Manfred

    2009-02-16

    Throughout their life, plants typically remain in one location utilizing sunlight for the synthesis of carbohydrates, which serve as their sole source of energy as well as building blocks of a protective extracellular matrix, called the cell wall. During the course of evolution, plants have repeatedly adapted to their respective niche,which is reflected in the changes of their body plan and the specific design of cell walls. Cell walls not only changed throughout evolution but also are constantly remodelled and reconstructed during the development of an individual plant, and in response to environmental stress or pathogen attacks. Carbohydrate-rich cell walls display complex designs, which together with the presence of phenolic polymers constitutes a barrier for microbes, fungi, and animals. Throughout evolution microbes have co-evolved strategies for efficient breakdown of cell walls. Our current understanding of cell walls and their evolutionary changes are limited as our knowledge is mainly derived from biochemical and genetic studies, complemented by a few targeted yet very informative imaging studies. Comprehensive plant cell wall models will aid in the re-design of plant cell walls for the purpose of commercially viable lignocellulosic biofuel production as well as for the timber, textile, and paper industries. Such knowledge will also be of great interest in the context of agriculture and to plant biologists in general. It is expected that detailed plant cell wall models will require integrated correlative multimodal, multiscale imaging and modelling approaches, which are currently underway.

  2. Modeling invasion of metastasizing cancer cells to bone marrow utilizing ecological principles

    Directory of Open Access Journals (Sweden)

    Chen Kun-Wan

    2011-10-01

    Full Text Available Abstract Background The invasion of a new species into an established ecosystem can be directly compared to the steps involved in cancer metastasis. Cancer must grow in a primary site, extravasate and survive in the circulation to then intravasate into target organ (invasive species survival in transport. Cancer cells often lay dormant at their metastatic site for a long period of time (lag period for invasive species before proliferating (invasive spread. Proliferation in the new site has an impact on the target organ microenvironment (ecological impact and eventually the human host (biosphere impact. Results Tilman has described mathematical equations for the competition between invasive species in a structured habitat. These equations were adapted to study the invasion of cancer cells into the bone marrow microenvironment as a structured habitat. A large proportion of solid tumor metastases are bone metastases, known to usurp hematopoietic stem cells (HSC homing pathways to establish footholds in the bone marrow. This required accounting for the fact that this is the natural home of hematopoietic stem cells and that they already occupy this structured space. The adapted Tilman model of invasion dynamics is especially valuable for modeling the lag period or dormancy of cancer cells. Conclusions The Tilman equations for modeling the invasion of two species into a defined space have been modified to study the invasion of cancer cells into the bone marrow microenvironment. These modified equations allow a more flexible way to model the space competition between the two cell species. The ability to model initial density, metastatic seeding into the bone marrow and growth once the cells are present, and movement of cells out of the bone marrow niche and apoptosis of cells are all aspects of the adapted equations. These equations are currently being applied to clinical data sets for verification and further refinement of the models.

  3. Three-Dimensional Gene Map of Cancer Cell Types: Structural Entropy Minimisation Principle for Defining Tumour Subtypes

    Science.gov (United States)

    Li, Angsheng; Yin, Xianchen; Pan, Yicheng

    2016-02-01

    In this study, we propose a method for constructing cell sample networks from gene expression profiles, and a structural entropy minimisation principle for detecting natural structure of networks and for identifying cancer cell subtypes. Our method establishes a three-dimensional gene map of cancer cell types and subtypes. The identified subtypes are defined by a unique gene expression pattern, and a three-dimensional gene map is established by defining the unique gene expression pattern for each identified subtype for cancers, including acute leukaemia, lymphoma, multi-tissue, lung cancer and healthy tissue. Our three-dimensional gene map demonstrates that a true tumour type may be divided into subtypes, each defined by a unique gene expression pattern. Clinical data analyses demonstrate that most cell samples of an identified subtype share similar survival times, survival indicators and International Prognostic Index (IPI) scores and indicate that distinct subtypes identified by our algorithms exhibit different overall survival times, survival ratios and IPI scores. Our three-dimensional gene map establishes a high-definition, one-to-one map between the biologically and medically meaningful tumour subtypes and the gene expression patterns, and identifies remarkable cells that form singleton submodules.

  4. Design Principles in Polymer-Fullerene BHJ Solar Cells: PBDTTPD as a Case Study

    KAUST Repository

    Beaujuge, Pierre

    2015-06-29

    Among Organic Electronics, solution-processable π-conjugated polymers are proving particularly promising in bulk-heterojunction (BHJ) solar cells with fullerene acceptors such as PCBM.[1] In recent years, great headway has been made in the development of efficient polymer donors across the community, with published power conversion efficiencies (PCE) >8% in single cells and >10% in tandems. In most reports, these systems involve elaborate repeat unit and side chain patterns, and deviating from those patterns induces substantial drops in device PCE. While the range of polymer design parameters that impact BHJ solar cell performance remains a matter of some debate, our recent developments indicate that the combination of side-chain substituents appended to the main chain critically impacts polymer performance. For example, in poly(benzo[1,2-b:4,5-b’]dithiophene–thieno[3,4-c]pyrrole-4,6-dione) (PBDTTPD), side-chain substituents of various size and branching impart distinct molecular packing distances (i.e., π–π stacking and lamellar spacing), varying degrees of nanostructural order in thin films, and preferential backbone orientation relative to the device substrate.[2-5] While these structural variations seem to correlate with BHJ solar cell performance, with power conversion efficiencies ranging from 4% to 8.5%,[2,3] we believe that other contributing parameters – such as the local conformations between the polymer and the fullerene, and the domain distribution/composition across the BHJ (i.e., pure/mixed phases) – should also be taken into account.[6,7] Other discrete modifications of PBDTTPD’s molecular structure affect polymer performance in BHJ solar cells with PCBM, and our recent developments emphasize how systematic structure-property relationship studies impact the design of efficient polymer donors for BHJ solar cell applications.[8-10] It is important to further our understanding of these effects as we look to continue improving BHJ solar

  5. Study on Effect of IH764-3, an Active Principle of Salviae miltiorrhizae, in Inducing Hepatic Stellate Cell Apoptosis

    Institute of Scientific and Technical Information of China (English)

    赵东强; 姜慧卿; 修贺明; 张晓岚

    2002-01-01

    Objective: To explore the anti-fibrotic mechanism of Salviae miltiorrhizae from the view of proliferation and apoptosis of hepatic stellate cells (HSC).Methods: IH764-3, an active principle of Salviae miltiorrhizae, was used to intervene in the cultured HSC in vitro. Cell proliferation was detected by methyl thiazolyl tetrazolium (MTT) method, and the cell apoptosis was examined by electron microscopy, flow cytometer and terminal deoxynucleotidyl transferase mediated dUTP nick-end-labeling method (TUNEL).Results: MTT showed that IH764-3 has obvious inhibition on the proliferation of HSC. Specific cell apoptosis figures of HSC, such as chromatin agglutination, were seen under electron microscopy in the IH764-3 treated group. By flow cytometer, it was shown that the HSC apoptosis rate in the IH764-3 treated group was higher than that in the control group, and the apoptosis inducing effect of IH764-3 was dose- and time-dependent. TUNEL analysis showed that the HSC apoptotsis rate was 28.3±1.5% after being incubated for 48 hrs with IH764-3, which was significantly higher than that in the control group (6.7±0.6%, P<0.05).Conclusion: IH764-3 could inhibit the proliferation of HSC and induce its apoptosis. These effects may be one of the anti-fibrotic mechanisms of Salviae miltiorrhizae.

  6. Metastatic renal cell carcinoma presenting as a breast mass in a woman with history of primary breast cancer

    OpenAIRE

    Balliauw, C; Termote, B; Steen, A.; Moerman, P; M. R. Christiaens; Van Ongeval, C

    2011-01-01

    Metastatic extramammary breast tumours are uncommon and differential diagnosis with primary breast carcinoma may prove to be difficult. We report a case of a metastasis of a renal cell cancer in the breast in a woman with a history of primary breast cancer. On follow-up of her breast carcinoma, a lump was detected via mammography and ultrasound. Core needle biopsy revealed a metastatic extramammary lesion originating from an asymptomatic renal cell carcinoma. We conclude that the diagnosis of...

  7. Solar cell array design handbook - The principles and technology of photovoltaic energy conversion

    Science.gov (United States)

    Rauschenbach, H. S.

    1980-01-01

    Photovoltaic solar cell array design and technology for ground-based and space applications are discussed from the user's point of view. Solar array systems are described, with attention given to array concepts, historical development, applications and performance, and the analysis of array characteristics, circuits, components, performance and reliability is examined. Aspects of solar cell array design considered include the design process, photovoltaic system and detailed array design, and the design of array thermal, radiation shielding and electromagnetic components. Attention is then given to the characteristics and design of the separate components of solar arrays, including the solar cells, optical elements and mechanical elements, and the fabrication, testing, environmental conditions and effects and material properties of arrays and their components are discussed.

  8. Modeling recombination processes and predicting energy conversion efficiency of dye sensitized solar cells from first principles

    Science.gov (United States)

    Ma, Wei; Meng, Sheng

    2014-03-01

    We present a set of algorithms based on solo first principles calculations, to accurately calculate key properties of a DSC device including sunlight harvest, electron injection, electron-hole recombination, and open circuit voltages. Two series of D- π-A dyes are adopted as sample dyes. The short circuit current can be predicted by calculating the dyes' photo absorption, and the electron injection and recombination lifetime using real-time time-dependent density functional theory (TDDFT) simulations. Open circuit voltage can be reproduced by calculating energy difference between the quasi-Fermi level of electrons in the semiconductor and the electrolyte redox potential, considering the influence of electron recombination. Based on timescales obtained from real time TDDFT dynamics for excited states, the estimated power conversion efficiency of DSC fits nicely with the experiment, with deviation below 1-2%. Light harvesting efficiency, incident photon-to-electron conversion efficiency and the current-voltage characteristics can also be well reproduced. The predicted efficiency can serve as either an ideal limit for optimizing photovoltaic performance of a given dye, or a virtual device that closely mimicking the performance of a real device under different experimental settings.

  9. Dye-Sensitized Solar Cells Based on the Principles and Materials of Photosynthesis: Mechanisms of Suppression and Enhancement of Photocurrent and Conversion Efficiency

    OpenAIRE

    Hiroyoshi Nagae; Takeshi Miki; Xiao-Feng Wang; Yasushi Koyama

    2009-01-01

    Attempts have been made to develop dye-sensitized solar cells based on the principles and materials of photosynthesis: We first tested photosynthetic pigments, carotenoids (Cars), chlorophylls (Chls) and their derivatives, to find sensitizers showing reasonable performance (photocurrent and conversion efficiency). We then tried to introduce the principles of photosynthesis, including electron transfer and energy transfer from Car to Phe a. Also, we tried co-sensitization using the pheophorbid...

  10. Using in-cell SHAPE-Seq and simulations to probe structure–function design principles of RNA transcriptional regulators

    Science.gov (United States)

    Takahashi, Melissa K.; Watters, Kyle E.; Gasper, Paul M.; Abbott, Timothy R.; Carlson, Paul D.; Chen, Alan A.

    2016-01-01

    Antisense RNA-mediated transcriptional regulators are powerful tools for controlling gene expression and creating synthetic gene networks. RNA transcriptional repressors derived from natural mechanisms called attenuators are particularly versatile, though their mechanistic complexity has made them difficult to engineer. Here we identify a new structure–function design principle for attenuators that enables the forward engineering of new RNA transcriptional repressors. Using in-cell SHAPE-Seq to characterize the structures of attenuator variants within Escherichia coli, we show that attenuator hairpins that facilitate interaction with antisense RNAs require interior loops for proper function. Molecular dynamics simulations of these attenuator variants suggest these interior loops impart structural flexibility. We further observe hairpin flexibility in the cellular structures of natural RNA mechanisms that use antisense RNA interactions to repress translation, confirming earlier results from in vitro studies. Finally, we design new transcriptional attenuators in silico using an interior loop as a structural requirement and show that they function as desired in vivo. This work establishes interior loops as an important structural element for designing synthetic RNA gene regulators. We anticipate that the coupling of experimental measurement of cellular RNA structure and function with computational modeling will enable rapid discovery of structure–function design principles for a diverse array of natural and synthetic RNA regulators. PMID:27103533

  11. Using in-cell SHAPE-Seq and simulations to probe structure-function design principles of RNA transcriptional regulators.

    Science.gov (United States)

    Takahashi, Melissa K; Watters, Kyle E; Gasper, Paul M; Abbott, Timothy R; Carlson, Paul D; Chen, Alan A; Lucks, Julius B

    2016-06-01

    Antisense RNA-mediated transcriptional regulators are powerful tools for controlling gene expression and creating synthetic gene networks. RNA transcriptional repressors derived from natural mechanisms called attenuators are particularly versatile, though their mechanistic complexity has made them difficult to engineer. Here we identify a new structure-function design principle for attenuators that enables the forward engineering of new RNA transcriptional repressors. Using in-cell SHAPE-Seq to characterize the structures of attenuator variants within Escherichia coli, we show that attenuator hairpins that facilitate interaction with antisense RNAs require interior loops for proper function. Molecular dynamics simulations of these attenuator variants suggest these interior loops impart structural flexibility. We further observe hairpin flexibility in the cellular structures of natural RNA mechanisms that use antisense RNA interactions to repress translation, confirming earlier results from in vitro studies. Finally, we design new transcriptional attenuators in silico using an interior loop as a structural requirement and show that they function as desired in vivo. This work establishes interior loops as an important structural element for designing synthetic RNA gene regulators. We anticipate that the coupling of experimental measurement of cellular RNA structure and function with computational modeling will enable rapid discovery of structure-function design principles for a diverse array of natural and synthetic RNA regulators. PMID:27103533

  12. Definition of stereotactic body radiotherapy. Principles and practice for the treatment of stage I non-small cell lung cancer

    International Nuclear Information System (INIS)

    This report from the Stereotactic Radiotherapy Working Group of the German Society of Radiation Oncology (Deutschen Gesellschaft fuer Radioonkologie, DEGRO) provides a definition of stereotactic body radiotherapy (SBRT) that agrees with that of other international societies. SBRT is defined as a method of external beam radiotherapy (EBRT) that accurately delivers a high irradiation dose to an extracranial target in one or few treatment fractions. Detailed recommendations concerning the principles and practice of SBRT for early stage non-small cell lung cancer (NSCLC) are given. These cover the entire treatment process; from patient selection, staging, treatment planning and delivery to follow-up. SBRT was identified as the method of choice when compared to best supportive care (BSC), conventionally fractionated radiotherapy and radiofrequency ablation. Based on current evidence, SBRT appears to be on a par with sublobar resection and is an effective treatment option in operable patients who refuse lobectomy. (orig.)

  13. Modeling invasion of metastasizing cancer cells to bone marrow utilizing ecological principles

    OpenAIRE

    Chen Kun-Wan; Pienta Kenneth J

    2011-01-01

    Abstract Background The invasion of a new species into an established ecosystem can be directly compared to the steps involved in cancer metastasis. Cancer must grow in a primary site, extravasate and survive in the circulation to then intravasate into target organ (invasive species survival in transport). Cancer cells often lay dormant at their metastatic site for a long period of time (lag period for invasive species) before proliferating (invasive spread). Proliferation in the new site has...

  14. Causality Principle

    OpenAIRE

    Chi, Do Minh

    2001-01-01

    We advance a famous principle - causality principle - but under a new view. This principle is a principium automatically leading to most fundamental laws of the nature. It is the inner origin of variation, rules evolutionary processes of things, and the answer of the quest for ultimate theories of the Universe.

  15. Mechanical Principle of Enhancing Cell-Substrate Adhesion via Pre-Tension in the Cytoskeleton

    OpenAIRE

    Chen, Bin; Gao, Huajian

    2010-01-01

    Motivated by our earlier study on the effect of pre-tension in gecko adhesion, here we investigate whether and how pre-tension in cytoskeleton influences cell adhesion by developing a stochastic-elasticity model of a stress fiber attached on a rigid substrate via molecular bonds. By comparing the variations in adhesion lifetime and observing the sequences of bond breaking with and without pre-tension in the stress fiber under the same applied force, we demonstrate that the effect of pre-tensi...

  16. Modeling the autistic cell: iPSCs recapitulate developmental principles of syndromic and nonsyndromic ASD.

    Science.gov (United States)

    Ben-Reuven, Lihi; Reiner, Orly

    2016-06-01

    The opportunity to model autism spectrum disorders (ASD) through generation of patient-derived induced pluripotent stem cells (iPSCs) is currently an emerging topic. Wide-scale research of altered brain circuits in syndromic ASD, including Rett Syndrome, Fragile X Syndrome, Angelman's Syndrome and sporadic Schizophrenia, was made possible through animal models. However, possibly due to species differences, and to the possible contribution of epigenetics in the pathophysiology of these diseases, animal models fail to recapitulate many aspects of ASD. With the advent of iPSCs technology, 3D cultures of patient-derived cells are being used to study complex neuronal phenotypes, including both syndromic and nonsyndromic ASD. Here, we review recent advances in using iPSCs to study various aspects of the ASD neuropathology, with emphasis on the efforts to create in vitro model systems for syndromic and nonsyndromic ASD. We summarize the main cellular activity phenotypes and aberrant genetic interaction networks that were found in iPSC-derived neurons of syndromic and nonsyndromic autistic patients. PMID:27111774

  17. A principle of economy predicts the functional architecture of grid cells.

    Science.gov (United States)

    Wei, Xue-Xin; Prentice, Jason; Balasubramanian, Vijay

    2015-01-01

    Grid cells in the brain respond when an animal occupies a periodic lattice of 'grid fields' during navigation. Grids are organized in modules with different periodicity. We propose that the grid system implements a hierarchical code for space that economizes the number of neurons required to encode location with a given resolution across a range equal to the largest period. This theory predicts that (i) grid fields should lie on a triangular lattice, (ii) grid scales should follow a geometric progression, (iii) the ratio between adjacent grid scales should be √e for idealized neurons, and lie between 1.4 and 1.7 for realistic neurons, (iv) the scale ratio should vary modestly within and between animals. These results explain the measured grid structure in rodents. We also predict optimal organization in one and three dimensions, the number of modules, and, with added assumptions, the ratio between grid periods and field widths. PMID:26335200

  18. Fast detection and quantification of Escherichia coli using the base principle of the microbial fuel cell.

    Science.gov (United States)

    Kim, Taegyu; Han, Jong-In

    2013-11-30

    Escherichia coli is an important microbial indicator of fecal contamination, making accurate quantitative detection of E. coli a key to ensuring public health. In this study, a microbial fuel cell (MFC) was used as a detection unit of an E. coli sensor, and specific enzymes expressed in E. coli, such as β-D-galactosidase (GAL) and β-D-glucuronidase (GUS), were exploited as biological detection elements. As substrates, 4-aminophenyl-β-D-galactopyranoside (4-APGal) were used for GAL detection, whereas 8-hydroxyquinoline glucuronide (8-HQG) and 4-nitrophenyl β-D-glucuronide (PNPG) were used for GUS detection. Once these substrates were hydrolyzed by GAL or GUS, they became electrochemically active products, which were, in turn, oxidized on the anode of the MFC reactor. The power output of the MFC reactor increased sharply when E. coli in the reactor reached the critical concentration. Accordingly, the time required to reach the highest voltage output was recorded as a detection time (DT), and a negative linear relationship was established between DT and the logarithm of the initial concentration of E. coli in the samples studied. The DTs of laboratory samples were 140 min and 560 min for initial concentrations of 1.9 × 10(7) CFU/mL and 42 CFU/mL at 44.5 °C. Moreover, the DTs for GUS assays were further shortened by induction with methyl β-D-glucuronide sodium salt (MetGlu). The quantitative relationship between DTs and initial E. coli concentrations established from replicate laboratory sample assays allowed estimation of the E. coli concentration in environmental samples, but with approximately 100 min of lag time. The lag time was also observed with E. coli samples that were prepared by starving cells in a laboratory. PMID:24095789

  19. Beyond Columnar Organization: Cell Type- and Target Layer-Specific Principles of Horizontal Axon Projection Patterns in Rat Vibrissal Cortex.

    Science.gov (United States)

    Narayanan, Rajeevan T; Egger, Robert; Johnson, Andrew S; Mansvelder, Huibert D; Sakmann, Bert; de Kock, Christiaan P J; Oberlaender, Marcel

    2015-11-01

    Vertical thalamocortical afferents give rise to the elementary functional units of sensory cortex, cortical columns. Principles that underlie communication between columns remain however unknown. Here we unravel these by reconstructing in vivo-labeled neurons from all excitatory cell types in the vibrissal part of rat primary somatosensory cortex (vS1). Integrating the morphologies into an exact 3D model of vS1 revealed that the majority of intracortical (IC) axons project far beyond the borders of the principal column. We defined the corresponding innervation volume as the IC-unit. Deconstructing this structural cortical unit into its cell type-specific components, we found asymmetric projections that innervate columns of either the same whisker row or arc, and which subdivide vS1 into 2 orthogonal [supra-]granular and infragranular strata. We show that such organization could be most effective for encoding multi whisker inputs. Communication between columns is thus organized by multiple highly specific horizontal projection patterns, rendering IC-units as the primary structural entities for processing complex sensory stimuli. PMID:25838038

  20. The active principle region of Buyang Huanwu decoction induced differentiation of bone marrow-derived mesenchymal stem cells into neural-like cells Superior effects over original formula of Buyang Huanwu decoction

    Institute of Scientific and Technical Information of China (English)

    Jinghui Zheng; Yi Wan; Jianhuai Chi; Dekai Shen; Tingting Wu; Weimin Li; Pengcheng Du

    2012-01-01

    The present study induced in vitro-cultured passage 4 bone marrow-derived mesenchymal stem cells to differentiate into neural-like cells with a mixture of alkaloid, polysaccharide, aglycone, glycoside, essential oils, and effective components of Buyang Huanwu decoction (active principle region of decoction for invigorating yang for recuperation). After 28 days, nestin and neuron-specific enolase were expressed in the cytoplasm. Reverse transcription-PCR and western blot analyses showed that nestin and neuron-specific enolase mRNA and protein expression was greater in the active principle region group compared with the original formula group. Results demonstrated that the active principle region of Buyang Huanwu decoction induced greater differentiation of rat bone marrow-derived mesenchymal stem cells into neural-like cells in vitro than the original Buyang Huanwu decoction formula.

  1. Principles of radiometric dating

    International Nuclear Information System (INIS)

    One of the major contributions that the study of meteorites has made to our understanding of the origin of the solar system is in defining when that event took place. In addition, several other important events in early solar-system history have been dated using radiochronological techniques applied to meteorites. The principles on which those applications of radiometric dating are based are outlined. 24 references

  2. Biomedical engineering principles

    CERN Document Server

    Ritter, Arthur B; Valdevit, Antonio; Ascione, Alfred N

    2011-01-01

    Introduction: Modeling of Physiological ProcessesCell Physiology and TransportPrinciples and Biomedical Applications of HemodynamicsA Systems Approach to PhysiologyThe Cardiovascular SystemBiomedical Signal ProcessingSignal Acquisition and ProcessingTechniques for Physiological Signal ProcessingExamples of Physiological Signal ProcessingPrinciples of BiomechanicsPractical Applications of BiomechanicsBiomaterialsPrinciples of Biomedical Capstone DesignUnmet Clinical NeedsEntrepreneurship: Reasons why Most Good Designs Never Get to MarketAn Engineering Solution in Search of a Biomedical Problem

  3. Mitogen activated protein kinase signaling pathways participate in the active principle region of Buyang Huanwu decoction-induced differentiation of bone marrow mesenchymal stem cells

    Institute of Scientific and Technical Information of China (English)

    Jinghui Zheng; Jian Liang; Xin Deng; Xiaofeng Chen; Fasheng Wu; Xiaofang Zhao; Yuan Luo; Lei Fu; Zuling Jiang

    2012-01-01

    Our preliminary studies confirmed that an active principle region of Buyang Huanwu decoction, comprising alkaloid, polysaccharide, aglycon, glucoside and volatile oil, can induce bone marrow mesenchymal stem cell differentiation into neurons. Mitogen-activated protein kinase signaling was identified as one of the key pathways underlying this differentiation process. The present study shows phosphorylated extracellular signal-regulated protein kinase and phosphorylated p38 protein expression was increased after differentiation. Cellular signaling pathway blocking agents, PD98059 and SB203580, inhibited extracellular signal-regulated protein kinase and p38 in mitogen-activated protein kinase signaling pathways respectively. mRNA and protein expression of the neuronal marker, neuron specific enolase, and neural stem cell marker, nestin, were decreased in bone marrow mesenchymal stem cells after treatment with the active principle region of Buyang Huanwu decoction. Experimental findings indicate that, extracellular signal-regulated protein kinase and p38 in mitogen-activated protein kinase signaling pathways participate in bone marrow mesenchymal stem cell differentiation into neuron-like cells, induced by the active principle region of Buyang Huanwu decoction.

  4. Recapitulating the History of Sickle-Cell Anemia Research: Improving Students' NOS Views Explicitly and Reflectively

    Science.gov (United States)

    Howe, Eric Michael; Rudge, David Wyss

    2005-01-01

    This paper provides an argument in favor of a specific pedagogical method of using the history of science to help students develop more informed views about nature of science (NOS) issues. The paper describes a series of lesson plans devoted to encouraging students to engage, "unbeknownst to them", in similar reasoning that led scientists to…

  5. Squamous Cell Carcinoma and Multiple Bowen's Disease in a Patient with a History of Consumption of Traditional Chinese Herbal Balls

    Directory of Open Access Journals (Sweden)

    Joon Seok

    2015-07-01

    Full Text Available Arsenic has been classified as a class I human carcinogen, meaning that there is sufficient evidence of carcinogenicity to humans. Arsenic, however, remains a common contaminant in a number of traditional Chinese herbal balls. A 64-year-old man presented with an erythematous erosive patch on the left palm, multiple yellowish scaly patches on the right palm and an erythematous hyperkeratotic patch with bleeding on the left foot dorsum. He also had similar skin lesions on the back and buttock. He had a past medical history of chronic exposure to arsenic through consumption of traditional Chinese herbal balls. Skin biopsy revealed Bowen's disease on the left palm and squamous cell carcinoma on left foot dorsum. We report this case to emphasize that we should investigate patient's history thoroughly, including the use of Chinese herbal balls to find out arsenicism.

  6. The Spurious Paternity of Business Communication Principles.

    Science.gov (United States)

    Hagge, John

    1989-01-01

    Examines the history of business communication principles. Concludes that principles supposedly developed for business communication can be found in turn-of-the-century composition textbooks and can be traced to a 2000-year-old tradition of epistolographic writings. Questions the viability of principles whose validity depends on rhetorical…

  7. DNA Methylation and Somatic Mutations Converge on the Cell Cycle and Define Similar Evolutionary Histories in Brain Tumors.

    Science.gov (United States)

    Mazor, Tali; Pankov, Aleksandr; Johnson, Brett E; Hong, Chibo; Hamilton, Emily G; Bell, Robert J A; Smirnov, Ivan V; Reis, Gerald F; Phillips, Joanna J; Barnes, Michael J; Idbaih, Ahmed; Alentorn, Agusti; Kloezeman, Jenneke J; Lamfers, Martine L M; Bollen, Andrew W; Taylor, Barry S; Molinaro, Annette M; Olshen, Adam B; Chang, Susan M; Song, Jun S; Costello, Joseph F

    2015-09-14

    The evolutionary history of tumor cell populations can be reconstructed from patterns of genetic alterations. In contrast to stable genetic events, epigenetic states are reversible and sensitive to the microenvironment, prompting the question whether epigenetic information can similarly be used to discover tumor phylogeny. We examined the spatial and temporal dynamics of DNA methylation in a cohort of low-grade gliomas and their patient-matched recurrences. Genes transcriptionally upregulated through promoter hypomethylation during malignant progression to high-grade glioblastoma were enriched in cell cycle function, evolving in parallel with genetic alterations that deregulate the G1/S cell cycle checkpoint. Moreover, phyloepigenetic relationships robustly recapitulated phylogenetic patterns inferred from somatic mutations. These findings highlight widespread co-dependency of genetic and epigenetic events throughout brain tumor evolution. PMID:26373278

  8. Review on first-principles study of defect properties of CdTe as a solar cell absorber

    Science.gov (United States)

    Yang, Ji-Hui; Yin, Wan-Jian; Park, Ji-Sang; Ma, Jie; Wei, Su-Huai

    2016-08-01

    CdTe is one of the leading materials for high-efficiency, low-cost, and thin-film solar cells. In this work, we review the recent first-principles study of defect properties of CdTe and present that: (1) When only intrinsic defects are present, p-type doping in CdTe is weak and the hole density is low due to the relatively deep acceptor levels of Cd vacancy. (2) When only intrinsic defects present, the dominant non-radiative recombination center in p-type CdTe is T{e}Cd2+, which limits the carrier lifetime to be around 200 ns. (3) Extrinsic p-type doping in CdTe by replacing Te with group V elements generally will be limited by the formation of AX centers. This could be overcome through a non-equilibrium cooling process and the hole density can achieve {10}17 {{{cm}}}-3. However, the long-term stability will be a challenging issue. (4) Extrinsic p-type doping by replacing Cd with alkaline group I elements is limited by alkaline interstitials and a non-equilibrium cooling process can efficiently enhance the hole density to the order of {10}17 {{{cm}}}-3. (5) Cu and Cl treatments are discussed. In bulk CdTe, Cu can enhance p-type doping, but Cl is found to be unsuitable for this. Both Cu and Cl show segregation at grain boundaries, especially at those with Te–Te wrong bonds. (6) External impurities are usually incorporated by diffusion. Therefore, the diffusion processes in CdTe are investigated. We find that cation interstitial (Nai, Cui) diffusion follows relatively simple diffusion paths, but anion diffusion (Cli, Pi) follows more complicated paths due to the degenerated defect wavefunctions.

  9. Definition of stereotactic body radiotherapy. Principles and practice for the treatment of stage I non-small cell lung cancer

    Energy Technology Data Exchange (ETDEWEB)

    Guckenberger, M.; Sauer, O. [University of Wuerzburg, Department of Radiation Oncology, Wuerzburg (Germany); Andratschke, N. [University of Rostock, Department of Radiotherapy and Radiation Oncology, Rostock (Germany); Alheit, H. [Distler Radiation Oncology, Bautzen/Pirna (Germany); Holy, R. [RWTH Aachen University, Department of Radiation Oncology, Aachen (Germany); Moustakis, C. [University of Muenster, Department of Radiation Oncology, Muenster (Germany); Nestle, U. [University of Freiburg, Department of Radiation Oncology, Freiburg (Germany)

    2014-01-15

    This report from the Stereotactic Radiotherapy Working Group of the German Society of Radiation Oncology (Deutschen Gesellschaft fuer Radioonkologie, DEGRO) provides a definition of stereotactic body radiotherapy (SBRT) that agrees with that of other international societies. SBRT is defined as a method of external beam radiotherapy (EBRT) that accurately delivers a high irradiation dose to an extracranial target in one or few treatment fractions. Detailed recommendations concerning the principles and practice of SBRT for early stage non-small cell lung cancer (NSCLC) are given. These cover the entire treatment process; from patient selection, staging, treatment planning and delivery to follow-up. SBRT was identified as the method of choice when compared to best supportive care (BSC), conventionally fractionated radiotherapy and radiofrequency ablation. Based on current evidence, SBRT appears to be on a par with sublobar resection and is an effective treatment option in operable patients who refuse lobectomy. (orig.) [German] Die Arbeitsgruppe ''Stereotaktische Radiotherapie'' der Deutschen Gesellschaft fuer Radioonkologie (DEGRO) erarbeitete eine Definition der Koerperstereotaxie (SBRT), die sich an vorhandene internationale Definitionen anlehnt: Die SBRT ist eine Form der perkutanen Strahlentherapie, die mit hoher Praezision eine hohe Bestrahlungsdosis in einer oder wenigen Bestrahlungsfraktionen in einem extrakraniellen Zielvolumen appliziert. Zur Praxis der SBRT beim nichtkleinzelligen Bronchialkarzinom (NSCLC) im fruehen Stadium werden detaillierte Empfehlungen gegeben, die den gesamten Ablauf der Behandlung von der Indikationsstellung, Staging, Behandlungsplanung und Applikation sowie Nachsorge umfassen. Die Koerperstereotaxie wurde als Methode der Wahl im Vergleich zu Best Supportive Care, zur konventionell fraktionierten Strahlentherapie sowie zur Radiofrequenzablation identifiziert. Die Ergebnisse nach SBRT und sublobaerer Resektion

  10. Review on First-Principles Study of Defect Properties of CdTe as a Solar Cell Absorber

    Energy Technology Data Exchange (ETDEWEB)

    Yang, Ji-Hui; Yin, Wan-Jian; Park, Ji-Sang; Ma, Jie; Wei, Su-Huai

    2016-08-01

    CdTe is one of the leading materials for high-efficiency, low-cost, and thin-film solar cells. In this work, we review the recent first-principles study of defect properties of CdTe and present that: (1) When only intrinsic defects are present, p-type doping in CdTe is weak and the hole density is low due to the relatively deep acceptor levels of Cd vacancy. (2) When only intrinsic defects present, the dominant non-radiative recombination center in p-type CdTe is Te-2+/Cd, which limits the carrier lifetime to be around 200 ns. (3) Extrinsic p-type doping in CdTe by replacing Te with group V elements generally will be limited by the formation of AX centers. This could be overcome through a non-equilibrium cooling process and the hole density can achieve 10^17 cm-3. However, the long-term stability will be a challenging issue. (4) Extrinsic p-type doping by replacing Cd with alkaline group I elements is limited by alkaline interstitials and a non-equilibrium cooling process can efficiently enhance the hole density to the order of 10^17 cm-3. (5) Cu and Cl treatments are discussed. In bulk CdTe, Cu can enhance p-type doping, but Cl is found to be unsuitable for this. Both Cu and Cl show segregation at grain boundaries, especially at those with Te-Te wrong bonds. (6) External impurities are usually incorporated by diffusion. Therefore, the diffusion processes in CdTe are investigated. We find that cation interstitial (Nai, Cui) diffusion follows relatively simple diffusion paths, but anion diffusion (Cli, Pi) follows more complicated paths due to the degenerated defect wavefunctions.

  11. Natural history, clinicopathologic classification and prognosis of gastric ECL cell tumors.

    OpenAIRE

    Solcia, E; Rindi, G.; Paolotti, D.; Luinetti, O; Klersy, C.; Zangrandi, A; de la Rosa, S.; Capella, C

    1998-01-01

    A series of 50 gastric endocrine tumors classified according to Rindi et al. [1] comprised 12 small cell neuroendocrine carcinomas (NEC) and 38 ECL cell carcinoids, of which 22 associated with type A chronic atrophic gastritis (A-CAG), eight with hypertrophic gastropathy due to combined Multiple Endocrine Neoplasia and Zollinger/Ellison syndrome (MEN/ZES), and eight sporadic. Variables found to predict tumor malignancy were: size > 2 cm, > 2 mitoses and > 130 Ki67 positive cells/10 high power...

  12. Life history evolution and the origin of multicellularity: the case of different types of cells

    OpenAIRE

    Aleskerov, Fuad; Tverskoy, Denis

    2015-01-01

    The problem of unicellular-multicellular transition is one of the main issues that is discussing in evolutionary biology. In [1] the fitness of a colony of cells is considered in terms of its two basic components, viability and fecundity. Intrinsic trade-off function of each cell defines a type of cell. We elaborate models providing in [1]. Assuming that all intrinsic trade-off functions are linear, we construct a model with different cell types and show that the differentiation of these type...

  13. Small cell neuroendocrine carcinoma of tracheostomy site in a patient with a history of juvenile laryngeal papillomatosis.

    Science.gov (United States)

    Violet Wilmot, Victoria; Nixon, Iain James; Nixon, Ioanna Fragkandrea

    2016-01-01

    Juvenile laryngeal papillomatosis is the commonest cause of benign epithelial tumours of the larynx. Following diagnostic biopsy, surgical debulking is the mainstay of therapy. The condition is often recurrent with further papillomas forming after debridement, requiring serial procedures and occasionally demanding tracheostomy. Rarely, the disease can undergo malignant transformation; most commonly to squamous cell carcinoma. We describe the first reported case of small cell neuroendocrine carcinoma occurring in the previous tracheostomy site of a 29-year-old male with a history of juvenile laryngeal papillomatosis. The patient, with a background of multiple treatments for juvenile papillomas, presented with voice change, breathing difficultly and erythema at the site of previous tracheostomy. Induction chemotherapy followed by chemoradiation was used to treat the lesion with a good response to initial therapy. PMID:27507691

  14. Using the history of research on sickle-cell anemia to affect preservice teachers' conceptions of the nature of science

    Science.gov (United States)

    Howe, Eric M.

    Preservice elementary teachers enrolled in an elective biology course participated in an eight-class unit of instruction based on the history of research in understanding the disease sickle-cell anemia. Students were introduced to the disease as a "mystery" for them to solve, and subsequently developed an understanding of the disease from several disciplines in biology (e.g., genetics, ecology, evolution, molecular biology). The unit involved open-ended problems in which students examined evidence and developed explanations in a manner analogous to the reasoning used by Anthony C. Allison and his colleagues during the early to middle part of the twentieth century. Throughout the unit, students were challenged to explicitly and reflectively connect their work with the historical material to more general conclusions about aspects of the nature of science. These aspects included (a) the nature of scientific theories, (b) the tentative nature of science, (c) the difference between scientific theories and laws, (d) the validity of observational methods in science, and (e) the subjective (theory-laden) nature of science. The research measured students' pre- and post-instruction views by using both an open-ended survey (VNOS) and follow-up, semi-structured interviews. The results indicated that an appreciable number of students underwent a change or enrichment in their views for some of the nature of science aspects. Moreover, change or enrichment in students' views was directly attributable to their work in the sickle-cell unit as evidenced from the specific examples students articulated in their post-instruction responses in support of their more informed views. In general, the findings of this research lend empirical support to the value of having students actively recapitulate the history of science to improve their nature of science conceptions. This is facilitated when the lessons challenge students to explicitly and reflectively develop views of the nature of

  15. Variational principles

    CERN Document Server

    Moiseiwitsch, B L

    2004-01-01

    This graduate-level text's primary objective is to demonstrate the expression of the equations of the various branches of mathematical physics in the succinct and elegant form of variational principles (and thereby illuminate their interrelationship). Its related intentions are to show how variational principles may be employed to determine the discrete eigenvalues for stationary state problems and to illustrate how to find the values of quantities (such as the phase shifts) that arise in the theory of scattering. Chapter-by-chapter treatment consists of analytical dynamics; optics, wave mecha

  16. Squamous cell carcinoma of hypopharynx in a patient with history of celiac disease

    Institute of Scientific and Technical Information of China (English)

    A Akhavan; A Seifadini

    2012-01-01

    Celiac disease is a gluten-related malabsorption in small intestine occurring in genetically susceptible patients. In this disease the risk of many malignancies is increased the most important of which being non-Hodgkin lymphoma of small intestine. Other malignancies include adenocarcinoma of small intestine and squamous cell carcinoma of esophagus and melanoma. As to our knowledge so far only one case of celiac disease associated with hypopharyngeal squamous cell carcinoma has been reported. In this article we presented a patient suffering from celiac disease with squamous cell carcinoma of hypopharynx. She underwent chemotherapy and radiation therapy, unfortunately however she died because of progress of disease. So, in patients with celiac disease we should pay attention to various malignancies and when cases of cancers are accompanied by malabsorption we must think of celiac disease involvement.

  17. Combination of Markov chain and optimal control solved by Pontryagin’s Minimum Principle for a fuel cell/supercapacitor vehicle

    International Nuclear Information System (INIS)

    Highlights: • A combination of Markov chain and an optimal control solved by Pontryagin’s Minimum Principle is presented. • This strategy is applied to hybrid electric vehicle dynamic model. • The hydrogen consumption is analyzed for two different vehicle mass and drive cycle. • The supercapacitor and fuel cell behavior is analyzed at high or sudden required power. - Abstract: In this article, a real time optimal control strategy based on Pontryagin’s Minimum Principle (PMP) combined with the Markov chain approach is used for a fuel cell/supercapacitor electrical vehicle. In real time, at high power and at high speed, two phenomena are observed. The first is obtained at higher required power, and the second is observed at sudden power demand. To avoid these situations, the Markov chain model is proposed to predict the future power demand during a driving cycle. The optimal control problem is formulated as an equivalent consumption minimization strategy (ECMS), that has to be solved by using the Pontryagin’s Minimum Principle. A Markov chain model is added as a separate block for a prediction of required power. This approach and the whole system are modeled and implemented using the MATLAB/Simulink. The model without Markov chain block and the model is with it are compared. The results presented demonstrate the importance of a Markov chain block added to a model

  18. Detection of Bovine Herpesvirus 4 (BoHV-4) DNA in the Cell Fraction of Milk of Dairy Cattle with History of BoHV-4 Infection

    OpenAIRE

    Donofrio, Gaetano; Flammini, Cesidio Filippo; Scatozza, Franco; Cavirani, Sandro

    2000-01-01

    We have demonstrated, by PCR and restriction enzyme analysis of the PCR product, the presence of bovine herpesvirus 4 (BoHV-4) DNA in the cell fraction of milk from dairy cattle with a history of BoHV-4 infection. We next evaluated the infectious nature of BoHV-4 DNA in those cells. Cocultivation of a BoHV-4-sensitive cell line with BoHV-4 DNA-positive milk cell samples produced cytopathic effects. The same result was obtained from frozen and thawed milk cell fraction coming from the cell mil...

  19. Natural history of neck disease in patients with squamous cell carcinoma of oropharynx and pharyngolarynx

    International Nuclear Information System (INIS)

    1666 patients with squamous cell carcinoma of oropharynx and pharyngolarynx, were evaluated on admission regarding the characteristic metastases patterns to their cervical lymph nodes. Preliminary therapeutic implications are derived from this nodal distribution. Comparisons are established between the 1978 UICC and 1976 AJC classifications, showing a good correlation despite multiple differences in staging criteria. It is shown that assessment combining both the multiplicity and the volume of cervical metastases allows to evaluate more accurately the aggressiveness of the primary. (Auth.)

  20. Natural History of Non-Small-Cell Lung Cancer with Bone Metastases

    OpenAIRE

    Santini Daniele; Barni Sandro; Intagliata Salvatore; Falcone Alfredo; Ferraù Francesco; Galetta Domenico; Moscetti Luca; La Verde Nicla; Ibrahim Toni; Petrelli Fausto; Vasile Enrico; Ginocchi Laura; Ottaviani Davide; Longo Flavia; Ortega Cinzia

    2015-01-01

    We conducted a large, multicenter, retrospective survey aimed to explore the impact of tumor bone involvement in Non-Small Cell Lung Cancer.Data on clinical-pathology, skeletal outcomes and bone-directed therapies for 661 deceased patients with evidence of bone metastasis were collected and statistically analyzed. Bone metastases were evident at diagnosis in 57.5% of patients. In the remaining cases median time to bone metastases appearance was 9 months. Biphosphonates were administered in 59...

  1. A review of the history, epidemiology and treatment of squamous cell carcinoma of the scrotum

    Directory of Open Access Journals (Sweden)

    Jerome Azike

    2009-07-01

    Full Text Available Squamous cell carcinoma of the scrotum is a tumor that is of interest for clinical and historical reasons. It was the first cancer linked to occupational exposure when, in 1775, Perivall Pott described it in chimney sweeps in England. Other occupations that had a preponderance of the disease included people who worked with the distillates of coal and men exposed to mineral oil. Currently, the disease is very rare and most cases are thought to result from poor hygiene and chronic irritation. Surgery with a negative resection margin offers the best hope of cure as adjunctive therapy has not proved useful. Prognosis correlates with the extent of nodal involvement.

  2. Ethical principles in health care research

    OpenAIRE

    Scott, Anne

    2013-01-01

    Chapter topics • The history of the evolving recognition of the need to regulate research involving human subjects • Consideration of some key ethical principles relevant to the research process • Applying ethical understanding in the practice of research

  3. Principles, problems and paradoxes of cosmogony

    International Nuclear Information System (INIS)

    Fundamental problems of cosmogony (such as the irreversible process of energy dissipation, adiabatic expansion of the universe, star and planet-system accretion) based on Newtonian principles are discussed according to Kant's 'Natural History of the Sky'

  4. Natural History of Non-Small-Cell Lung Cancer with Bone Metastases

    Science.gov (United States)

    Daniele, Santini; Sandro, Barni; Salvatore, Intagliata; Alfredo, Falcone; Francesco, Ferraù; Domenico, Galetta; Luca, Moscetti; Nicla, La Verde; Toni, Ibrahim; Fausto, Petrelli; Enrico, Vasile; Laura, Ginocchi; Davide, Ottaviani; Flavia, Longo; Cinzia, Ortega; Antonio, Russo; Giuseppe, Badalamenti; Elena, Collovà; Gaetano, Lanzetta; Giovanni, Mansueto; Vincenzo, Adamo; Filippo, De Marinis; Satolli, Maria Antonietta; Flavia, Cantile; Andrea, Mancuso; Tanca, Francesca Maria; Raffaele, Addeo; Marco, Russano; Sterpi, M; Francesco, Pantano; Bruno, Vincenzi; Giuseppe, Tonini

    2015-01-01

    We conducted a large, multicenter, retrospective survey aimed to explore the impact of tumor bone involvement in Non-Small Cell Lung Cancer.Data on clinical-pathology, skeletal outcomes and bone-directed therapies for 661 deceased patients with evidence of bone metastasis were collected and statistically analyzed. Bone metastases were evident at diagnosis in 57.5% of patients. In the remaining cases median time to bone metastases appearance was 9 months. Biphosphonates were administered in 59.6% of patients. Skeletal-related events were experienced by 57.7% of patients; the most common was the need for radiotherapy. Median time to first skeletal-related event was 6 months. Median survival after bone metastases diagnosis was 9.5 months and after the first skeletal-related event was 7 months. We created a score based on four factors used to predict the overall survival from the diagnosis of bone metastases: age >65 years, non-adenocarcinoma histology, ECOG Performance Status >2, concomitant presence of visceral metastases at the bone metastases diagnosis. The presence of more than two of these factors is associated with a worse prognosis.This study demonstrates that patients affected by Non-Small Cell Lung Cancer with bone metastases represent a heterogeneous population in terms of risk of skeletal events and survival. PMID:26690845

  5. Bohmian Histories and Decoherent Histories

    OpenAIRE

    Hartle, James B.

    2002-01-01

    The predictions of the Bohmian and the decoherent (or consistent) histories formulations of the quantum mechanics of a closed system are compared for histories -- sequences of alternatives at a series of times. For certain kinds of histories, Bohmian mechanics and decoherent histories may both be formulated in the same mathematical framework within which they can be compared. In that framework, Bohmian mechanics and decoherent histories represent a given history by different operators. Their ...

  6. Quantum Histories and Quantum Gravity

    OpenAIRE

    Henson, Joe

    2009-01-01

    This paper reviews the histories approach to quantum mechanics. This discussion is then applied to theories of quantum gravity. It is argued that some of the quantum histories must approximate (in a suitable sense) to classical histories, if the correct classical regime is to be recovered. This observation has significance for the formulation of new theories (such as quantum gravity theories) as it puts a constraint on the kinematics, if the quantum/classical correspondence principle is to be...

  7. Kinetic energy discrimination in collision/reaction cell ICP-MS: Theoretical review of principles and limitations

    International Nuclear Information System (INIS)

    Kinetic energy discrimination (KED) is one of the means to control cell-formed interferences in collision/reaction cell ICP-MS, and also a technique to reduce polyatomic ion interferences derived from the plasma or vacuum interface in collision cell ICP-MS. The operation of KED is accurately described to explain how spectral interferences from polyatomic ions are reduced by this technique. The cell is operated under non-thermal conditions to implement KED, where the hard sphere collision model is aptly employed to portray the transmission of ions colliding with the cell gas that they don't chemically react with. It is theoretically explained that the analyte atomic ions surmount the energy barrier placed downstream of the cell and the interfering polyatomic ions do not due to their lower kinetic energy than the atomic ions, resulting in polyatomic interference reduction. The intrinsic limitations of this technique are shown to lie in the statistical nature of collision processes, which causes the broadening of ion kinetic energy distribution that hinders efficient KED. The reaction cell operation with KED, where plasma-derived interferences are reduced by the reactive cell gas while cell-formed interferences are suppressed by the energy barrier, is also described in a quantitative manner. This review paper provides an in-depth understanding of KED in cell-based ICP-MS for analysts to make better use of it. - Highlights: • Hard sphere collision model was employed to describe the polyatomic ion interference reduction by KED. • The intrinsic limitations of KED lies in the statistical nature of collision processes. • It was shown that lighter collision gas is more effective than heavier one for polyatomic ion reduction by KED. • In non-thermal H2 reaction cell ICP-MS, KED does not contribute to the reduction of plasma-based interfering ions

  8. Towards a Novel Spatially-Resolved Hemolysis Detection Method Using a Fluorescent Indicator and Loaded Ghost Cells: Proof-of-Principle.

    Science.gov (United States)

    Jansen, Sebastian V; Müller, Indra; Kiesendahl, Nicole; Schmitz-Rode, Thomas; Steinseifer, Ulrich

    2015-09-01

    It is of the utmost importance to reduce flow-induced hemolysis in devices such as heart-valve prostheses and blood pumps. Thus, in vitro measurements of hemolysis are performed in order to optimize their design in this regard. However, with existing measurement methods, hemolysis can only be assessed as an integrated value over the complete test-circuit. Currently, there are no spatially-resolved in vitro hemolysis measurement techniques known to the authors that would allow for a determination of the critical regions within a device. In this study, a novel spatially-resolved measurement principle is proposed. Ghost cells (i.e. erythrocytes with a lower hemoglobin concentration) were loaded with a calcium-dicitrato complex, and a fluorescent calcium indicator was suspended in the extracellular medium. Calcium and indicator are separated until the cell membrane ruptures (i.e. hemolysis occurs). In the moment of hemolysis, the two compounds bind to each other and emit a fluorescent signal that can be recorded and spatially-resolved in a setup very similar to a standard Particle Image Velocimetry measurement. A proof-of-principle experiment was performed by intentionally inducing hemolysis in a flow-model with a surfactant. The surfactant-induced hemolysis demonstrated a clear increase of the fluorescent signal compared to that of a negative reference. Furthermore, the signal was spatially restricted to the area of hemolysis. Although further challenges need to be addressed, a successful proof-of-principle for novel spatially-resolved hemolysis detection is presented. This method can contribute to better design optimization of devices with respect to flow-induced hemolysis. PMID:26577368

  9. Bioreactor principles

    Science.gov (United States)

    2001-01-01

    Cells cultured on Earth (left) typically settle quickly on the bottom of culture vessels due to gravity. In microgravity (right), cells remain suspended and aggregate to form three-dimensional tissue. The NASA Bioreactor provides a low turbulence culture environment which promotes the formation of large, three-dimensional cell clusters. The Bioreactor is rotated to provide gentle mixing of fresh and spent nutrient without inducing shear forces that would damage the cells. Due to their high level of cellular organization and specialization, samples constructed in the bioreactor more closely resemble the original tumor or tissue found in the body. The work is sponsored by NASA's Office of Biological and Physical Research. The bioreactor is managed by the Biotechnology Cell Science Program at NASA's Johnson Space Center (JSC). NASA-sponsored bioreactor research has been instrumental in helping scientists to better understand normal and cancerous tissue development. In cooperation with the medical community, the bioreactor design is being used to prepare better models of human colon, prostate, breast and ovarian tumors. Cartilage, bone marrow, heart muscle, skeletal muscle, pancreatic islet cells, liver and kidney are just a few of the normal tissues being cultured in rotating bioreactors by investigators.

  10. Impedance spectroscopy assisted by magnetic nanoparticles as a potential biosensor principle for breast cancer cells in suspension

    International Nuclear Information System (INIS)

    Breast cancer (BC) is the leading cause of cancer death in women worldwide, with a higher mortality reported in undeveloped countries. Ideal adjuvant therapeutic strategies require the continuous monitoring of patients by regular blood tests to detect circulating cancer cells, in order to determine whether additional treatment is necessary to prevent cancer dissemination. This circumstance requires a non-complex design of tumor cell biosensor in whole blood with feasibility for use in poor regions. In this work we have evaluated an inexpensive and simple technique of relative bioimpedance measurement, assisted by magnetic nanoparticles, as a potential biosensor of BC cells in suspension. Measurements represent the relative impedance changes caused by the magnetic holding of an interphase of tumor cells versus a homogenous condition in the frequency range of 10–100 kHz. The results indicate that use of a magnet to separate tumor cells in suspension, coupled to magnetic nanoparticles, is a feasible technique to fix an interphase of tumor cells in close proximity to gold electrodes. Relative impedance changes were shown to have potential value as a biosensor method for BC cells in whole blood, at frequencies around 20 kHz. Additional studies are warranted with respect to electrode design and sensitivity at micro-scale levels, according to the proposed technique. (paper)

  11. An Essay About Oral History and Mathematical Education: setting principles and procedures Um Ensaio Sobre História Oral e Educação Matemática: pontuando princípios e procedimentos

    OpenAIRE

    Rosinéte Gaertner; Ivete Maria Baraldi

    2008-01-01

    Recently, we can perceive an intensification of assignments developed into Mathematical Education with the use of oral history as a research methodology. In this article, facing the living experiences during the preparation of our Phd tasks and later, when we had the role of advisors of scientific papers and of Postgraduate students in their researches also using the same methodology, we discussed the implication of ethics, mathematical education and oral history. Furthermore, we enunciated p...

  12. First principles study of Bi dopen CdTe thin film solar cells: electronic and optical properties

    OpenAIRE

    Seminóvski Pérez, Yohanna; Palacios Clemente, Pablo; Wahnón Benarroch, Perla

    2011-01-01

    Nowadays, efficiency improvement of solar cells is one of the most important issues in photovoltaic systems and CdTe is one of the most promising thin film photovoltaic materials we can found. CdTe reported efficiencies in solar energy conversion have been as good as that found in polycrystalline Si thin film cell [1], besides CdTe can be easily produced at industrial scale.

  13. Dynamic modeling and predictive control in solid oxide fuel cells first principle and data-based approaches

    CERN Document Server

    Huang, Biao; Murshed, A K M Monjur

    2012-01-01

    The high temperature solid oxide fuel cell (SOFC) is identified as one of the leading fuel cell technology contenders to capture the energy market in years to come. However, in order to operate as an efficient energy generating system, the SOFC requires an appropriate control system which in turn requires a detailed modelling of process dynamics. Introducting state-of-the-art dynamic modelling, estimation, and control of SOFC systems, this book presents original modelling methods and brand new results as developed by the authors. With comprehensive coverage and bringing together many

  14. Differences in history of sexual behavior between patients with oropharyngeal squamous cell carcinoma and patients with squamous cell carcinoma at other head and neck sites

    Science.gov (United States)

    Dahlstrom, Kristina R.; Li, Guojun; Tortolero-Luna, Guillermo; Wei, Qingyi; Sturgis, Erich M.

    2010-01-01

    Background An emerging epidemic of human papillomavirus (HPV)-associated oropharyngeal cancer has been proposed. We compared the sexual behaviors of patients with squamous cell carcinoma of the oropharynx (SCCOP) and patients with squamous cell carcinoma of non-oropharyngeal head and neck sites (SCCNOP) to expand our understanding of sexual behavior as a risk factor for HPV-associated head and neck cancer. Methods The sexual history of 165 SCCOP patients and 87 SCCNOP patients was determined in a hospital-based case-case comparison study. Results SCCOP patients were significantly more likely than SCCNOP patients to have had >9 lifetime sex partners (odds ratio [OR]=39.2; 95% confidence interval [CI]=8.2–187.3), to have engaged in oral-genital sex (OR=3.5; 95% CI=1.1–11.1), and to have had > 4 oral-genital sex partners (OR=8.6; 95% CI=2.2–33.4). Conclusions The findings of this study suggest that some risk factors are site specific and provide further evidence that certain sexual behaviors increase the risk of HPV-associated SCCOP. PMID:20737488

  15. Family History

    Science.gov (United States)

    ... Brain Aneurysm Statistics and Facts Seeking Medical Attention Pediatric Aneurysms Brain Aneurysm Causes and Risk Factors Family History ... Brain Aneurysm Statistics and Facts Seeking Medical Attention Pediatric Aneurysms Brain Aneurysm Causes and Risk Factors Family History ...

  16. "Sickle Cell Anemia: Tracking down a Mutation": An Interactive Learning Laboratory That Communicates Basic Principles of Genetics and Cellular Biology

    Science.gov (United States)

    Jarrett, Kevin; Williams, Mary; Horn, Spencer; Radford, David; Wyss, J. Michael

    2016-01-01

    "Sickle cell anemia: tracking down a mutation" is a full-day, inquiry-based, biology experience for high school students enrolled in genetics or advanced biology courses. In the experience, students use restriction endonuclease digestion, cellulose acetate gel electrophoresis, and microscopy to discover which of three putative patients…

  17. Metaphysics of the Principle of Least Action

    CERN Document Server

    Terekhovich, Vladislav

    2015-01-01

    Despite the importance of the variational principles of physics, there have been relatively few attempts to consider them for a realistic framework. In addition to the old teleological question, this paper continues the recent discussion regarding the modal involvement of the principle of least action and its relations with the Humean view of the laws of nature. The reality of the possible paths in the principle of least action is examined from the perspectives of the contemporary metaphysics of modality and Leibniz's concept of the possibles striving from essence to existence. This paper introduces a model of a two-level modality based on an intuition that deep ontological connections exist between the possible paths in the principle of least action and possible quantum histories in the Feynman path integral. The proposed modal interpretation of the principle of least action replaces the classical representation of the system's motion along a single history in the actual modality by the simultaneous motions ...

  18. Uranium enrichment. Principles

    International Nuclear Information System (INIS)

    Uranium enrichment industry is a more than 60 years old history and has developed without practically no cost, efficiency or profit constraints. However, remarkable improvements have been accomplished since the Second World War and have led to the development of various competing processes which reflect the diversity of uranium compositions and of uranium needs. Content: 1 - general considerations: uranium isotopes, problem of uranium enrichment, first realizations (USA, Russia, Europe, Asia, other countries), present day situation, future needs and market evolution; 2 - principles of isotopic separation: processes classification (high or low enrichment), low elementary enrichment processes, equilibrium time, cascade star-up and monitoring, multi-isotopes case, uranium reprocessing; 3 - enrichment and proliferation. (J.S.)

  19. Effects of turmeric and its active principle, curcumin, on bleomycin-induced chromosome aberrations in Chinese hamster ovary cells

    Directory of Open Access Journals (Sweden)

    Maria Cristina P. Araújo

    1999-09-01

    Full Text Available Naturally occurring antioxidants have been extensively studied for their capacity to protect organisms and cells from oxidative damage. Many plant constituents including turmeric and curcumin appear to be potent antimutagens and antioxidants. The effects of turmeric and curcumin on chromosomal aberration frequencies induced by the radiomimetic agent bleomycin (BLM were investigated in Chinese hamster ovary (CHO cells. Three concentrations of each drug, turmeric (100, 250 and 500 mg/ml and curcumin (2.5, 5 and 10 mg/ml, were combined with BLM (10 mg/ml in CHO cells treated during the G1/S, S or G2/S phases of the cell cycle. Neither turmeric nor curcumin prevented BLM-induced chromosomal damage in any phases of the cell cycle. Conversely, a potentiation of the clastogenicity of BLM by curcumin was clearly observed in cells treated during the S and G2/S phases. Curcumin was also clastogenic by itself at 10 µg/ml in two protocols used. However, the exact mechanism by which curcumin produced clastogenic and potentiating effects remains unknown.Antioxidantes de ocorrência natural têm sido exaustivamente estudados quanto a sua capacidade de proteger organimos e células contra danos oxidativos. Muitos constituintes das plantas, incluindo cúrcuma e curcumina, parecem ser potentes antimutágenos e antioxidantes. Os efeitos de cúrcuma e curcumina na freqüência de aberrações cromossômicas induzidas pelo agente radiomimético bleomicina (BLM foram investigados em células do ovário de hamster chinês (CHO. Três concentrações de cada droga, cúrcuma (100, 250 e 500 mg/ml e curcumina (2,5, 5,0 e 10 mg/ml, foram combinadas com BLM (10 mg/ml em células CHO tratadas durante as fases G1/S, S ou G2/S do ciclo celular. Nem cúrcuma nem curcumina evitaram o dano cromossômico induzido pela BLM em fase alguma do ciclo celular. Ao contrário, a potenciação da clastogenicidade da BLM pelo curcumina foi nitidamente observada em células tratadas

  20. A Focused Low-Intensity Pulsed Ultrasound (FLIPUS) System for Cell Stimulation: Physical and Biological Proof of Principle.

    Science.gov (United States)

    Puts, Regina; Ruschke, Karen; Ambrosi, Thomas H; Kadow-Romacker, Anke; Knaus, Petra; Jenderka, Klaus-Vitold; Raum, Kay

    2016-01-01

    Quantitative ultrasound (QUS) is a promising technique for bone tissue evaluation. Highly focused transducers used for QUS also have the capability to be applied for tissue-regenerative purposes and can provide spatially limited deposition of acoustic energy. We describe a focused low-intensity pulsed ultrasound (FLIPUS) system, which has been developed for the stimulation of cell monolayers in the defocused far field of the transducer through the bottom of the well plate. Tissue culture well plates, carrying the cells, were incubated in a special chamber, immersed in a temperature-controlled water tank. A stimulation frequency of 3.6 MHz provided an optimal sound transmission through the polystyrene well plate. The ultrasound was pulsed for 20 min daily at 100-Hz repetition frequency with 27.8% duty cycle. The calibrated output intensity corresponded to I(SATA) = 44.5 ± 7.1 mW/cm2, which is comparable to the most frequently reported nominal output levels in LIPUS studies. No temperature change by the ultrasound exposure was observed in the well plate. The system was used to stimulate rat mesenchymal stem cells (rMSCs). The applied intensity had no apoptotic effect and enhanced the expression of osteogenic markers, i.e., osteopontin (OPN), collagen 1 (Col-1), the osteoblast-specific transcription factor-Runx-2 and E11 protein, an early osteocyte marker, in stimulated cells on day 5. The proposed FLIPUS setup opens new perspectives for the evaluation of the mechanistic effects of LIPUS. PMID:26552085

  1. Time-targeted therapy (TTT): Proof of principle using doxorubicin and radiation in a cultured cell system

    International Nuclear Information System (INIS)

    We test the hypothesis that a pulse of the anti-cancer agent doxorubicin renders cells more sensitive to ionizing radiation in a strongly time-specific, dose-specific manner. We have treated cultured cells from a human tumor line, HepG2, with graded doses of two agents: doxorubicin (Dox) and ionizing radiation (XR), delivered in sequence-specific, time-specific, dose-specific patterns. We observe a strong increase in cell killing, up to 120 fold, between pulsed treatment with Dox followed exactly 4 hours later with acute XR. This effect is more pronounced for larger doses of irradiation (>7.5 Gy). These data demonstrate proof of principal in a model system that timing between agents may be an exceptionally important variable in using combined, multi-modal therapy in the treatment of cancer. Since the levels of Dox needed to induce substantial increases in cellular radiosensitivity may be achievable in vivo, we suggest that this phenomenon, which we refer to as time-targeted therapy (TTT), be considered for translation into the clinic if preclinical studies identify appropriate timing and toxicity for combined of Dox XR can be overcome

  2. Principles of the Olympic movement

    OpenAIRE

    2010-01-01

    The aim of this article is to clarify, review and reflect on the importance of the Olympic movement main principles on nowadays sporting society. For this purpose, the paper goes through the contents of the Olympic Charter, the threats to humanist thinking, the Olympic Games history and the most recent contributions to the Olympic philosophy. Similarly, this article goes deep on the figure of Pierre de Coubertin as the precursor of modern Olympic Games leading to the development of a relation...

  3. Application of the Principles of Systems Biology and Wiener's Cybernetics for Analysis of Regulation of Energy Fluxes in Muscle Cells in Vivo

    Directory of Open Access Journals (Sweden)

    Rita Guzun

    2010-03-01

    Full Text Available The mechanisms of regulation of respiration and energy fluxes in the cells are analyzed based on the concepts of systems biology, non-equilibrium steady state kinetics and applications of Wiener’s cybernetic principles of feedback regulation. Under physiological conditions cardiac function is governed by the Frank-Starling law and the main metabolic characteristic of cardiac muscle cells is metabolic homeostasis, when both workload and respiration rate can be changed manifold at constant intracellular level of phosphocreatine and ATP in the cells. This is not observed in skeletal muscles. Controversies in theoretical explanations of these observations are analyzed. Experimental studies of permeabilized fibers from human skeletal muscle vastus lateralis and adult rat cardiomyocytes showed that the respiration rate is always an apparent hyperbolic but not a sigmoid function of ADP concentration. It is our conclusion that realistic explanations of regulation of energy fluxes in muscle cells require systemic approaches including application of the feedback theory of Wiener’s cybernetics in combination with detailed experimental research. Such an analysis reveals the importance of limited permeability of mitochondrial outer membrane for ADP due to interactions of mitochondria with cytoskeleton resulting in quasi-linear dependence of respiration rate on amplitude of cyclic changes in cytoplasmic ADP concentrations. The system of compartmentalized creatine kinase (CK isoenzymes functionally coupled to ANT and ATPases, and mitochondrial-cytoskeletal interactions separate energy fluxes (mass and energy transfer from signalling (information transfer within dissipative metabolic structures – intracellular energetic units (ICEU. Due to the non-equilibrium state of CK reactions, intracellular ATP utilization and mitochondrial ATP regeneration are interconnected by the PCr flux from mitochondria. The feedback regulation of respiration occurring via

  4. Taking of history

    DEFF Research Database (Denmark)

    Langebæk, Rikke

    2007-01-01

    Learning how to take a history is an extremely important discipline in the education of veterinary students. In our opinion the fact that this discipline is often neglected in traditional teaching is a big mistake. The mere thought of facing a real client can be almost paralysing to even the...... smartest student. So the more familiar a student can become with these situations the better. Since september 2006, veterinary students at Faculty of Life Sciences, University of Copenhagen, have received training in the discipline of history taking, using innovative educational methods: Online The...... students prepare themselves for the course by going online at home the day before class. Here they find a narrated PowerPoint presentation containing : 1) The principles of history taking 2) Client diversities – and the obstacles one might have to face with these different types of clients Video In class a...

  5. Equivalence principles and electromagnetism

    Science.gov (United States)

    Ni, W.-T.

    1977-01-01

    The implications of the weak equivalence principles are investigated in detail for electromagnetic systems in a general framework. In particular, it is shown that the universality of free-fall trajectories (Galileo weak equivalence principle) does not imply the validity of the Einstein equivalence principle. However, the Galileo principle plus the universality of free-fall rotation states does imply the Einstein principle.

  6. First principles simulation of laser-induced periodic surface structure using the particle-in-cell method

    Science.gov (United States)

    Mitchell, Robert A.; Schumacher, Douglass W.; Chowdhury, Enam A.

    2015-11-01

    We present our results of a fundamental simulation of a periodic grating structure formation on a copper target during the femtosecond-pulse laser damage process, and compare our results to recent experiment. The particle-in-cell (PIC) method is used to model the initial laser heating of the electrons, a two-temperature model (TTM) is used to model the thermalization of the material, and a modified PIC method is employed to model the atomic transport leading to a damage crater morphology consistent with experimental grating structure formation. This laser-induced periodic surface structure (LIPSS) is shown to be directly related to the formation of surface plasmon polaritons (SPP) and their interference with the incident laser pulse.

  7. (Sr,Ba)(Si,Ge)2 for thin-film solar-cell applications: First-principles study

    Science.gov (United States)

    Kumar, Mukesh; Umezawa, Naoto; Imai, Motoharu

    2014-05-01

    In order to meet the increasing demand for electric power generation from solar energy conversion, the development of efficient light absorber materials has been awaited. To this end, the electronic and optical properties of advanced alkaline-earth-metals disilicides and digermanides (SrSi2, BaSi2, SrGe2, and BaGe2) are studied by means of the density functional theory using HSE06 exchange-correlation energy functional. Our calculations show that all these orthorhombic structured compounds have fundamental indirect band gaps in the range Eg ≈ 0.89-1.25 eV, which is suitable for solar cell applications. The estimated lattice parameters and band gaps are in good agreement with experiments. Our calculations show that the electronic band structures of all four compounds are very similar except in the vicinity of the Γ-point. The valence band of these compounds is made up by Si(Ge)-p states, whereas the conduction band is composed of Sr(Ba)-d states. Their band alignments are carefully determined by estimating the work function of each compound using slab model. The optical properties are discussed in terms of the complex dielectric function ɛ(ω) = ɛ1(ω) + iɛ2(ω). The static and high-frequency dielectric constants are calculated, taking into account the ionic contribution. The absorption coefficient α(ω) demonstrates that a low energy dispersion of the conduction band, which results in a flat conduction band minimum, leads to large optical activity in these compounds. Therefore, alkaline-earth-metals disilicides and digermanides possess great potential as light absorbers for applications in thin-film solar cell technologies.

  8. (Sr,Ba)(Si,Ge)2 for thin-film solar-cell applications: First-principles study

    International Nuclear Information System (INIS)

    In order to meet the increasing demand for electric power generation from solar energy conversion, the development of efficient light absorber materials has been awaited. To this end, the electronic and optical properties of advanced alkaline-earth-metals disilicides and digermanides (SrSi2, BaSi2, SrGe2, and BaGe2) are studied by means of the density functional theory using HSE06 exchange-correlation energy functional. Our calculations show that all these orthorhombic structured compounds have fundamental indirect band gaps in the range Eg ≈ 0.89–1.25 eV, which is suitable for solar cell applications. The estimated lattice parameters and band gaps are in good agreement with experiments. Our calculations show that the electronic band structures of all four compounds are very similar except in the vicinity of the Γ-point. The valence band of these compounds is made up by Si(Ge)-p states, whereas the conduction band is composed of Sr(Ba)-d states. Their band alignments are carefully determined by estimating the work function of each compound using slab model. The optical properties are discussed in terms of the complex dielectric function ε(ω) = ε1(ω) + iε2(ω). The static and high-frequency dielectric constants are calculated, taking into account the ionic contribution. The absorption coefficient α(ω) demonstrates that a low energy dispersion of the conduction band, which results in a flat conduction band minimum, leads to large optical activity in these compounds. Therefore, alkaline-earth-metals disilicides and digermanides possess great potential as light absorbers for applications in thin-film solar cell technologies.

  9. The natural history of pancreatic acinar cell cystadenoma: Is resection better than surveillance? An update to a case report from 2010

    OpenAIRE

    Darcy, David G.; Dominique Jan

    2016-01-01

    Cystic lesions of the pancreas are a rare entity, and few reports have described their natural history in children. A previously published report described a 9-year-old boy with an acinar cell cystadenoma, discovered during a laparoscopic appendectomy. Initially asymptomatic and followed by serial MRI, this patient presented to our institution several years later with chronic obstructive symptoms that required surgical intervention. Planning for resection included multidisciplinary input from...

  10. Principles of speech coding

    CERN Document Server

    Ogunfunmi, Tokunbo

    2010-01-01

    It is becoming increasingly apparent that all forms of communication-including voice-will be transmitted through packet-switched networks based on the Internet Protocol (IP). Therefore, the design of modern devices that rely on speech interfaces, such as cell phones and PDAs, requires a complete and up-to-date understanding of the basics of speech coding. Outlines key signal processing algorithms used to mitigate impairments to speech quality in VoIP networksOffering a detailed yet easily accessible introduction to the field, Principles of Speech Coding provides an in-depth examination of the

  11. Transplant of bone marrow and cord blood hematopoietic stem cells in pediatric practice, revisited according to the fundamental principles of bioethics.

    Science.gov (United States)

    Burgio, G R; Locatelli, F

    1997-06-01

    The two most widely used sources of hematopoietic stem cells for allogeneic transplants in pediatric practice are bone marrow (BM) and cord blood (CB). While bone marrow transplantation (BMT) is reaching its 30th year of application, human umbilical cord blood transplantation (HUCBT) is approaching its 10th. Although these procedures have basically the same purpose, a number of biological differences distinguish them. In particular, the intrinsically limited quantity of CB stem cells and their immunological naiveté confer peculiar characteristics to these hematopoietic progenitors. From a bioethical point of view, the problems which have repeatedly been raised when the BM donor is a child are well-known. Different but no less important ethical problems are raised when one considers HUCBT; in this regard the most important issues are the easier propensity of programming a CB donor in comparison with a BM donor (clearly due to the shorter time interval needed to collect the hematopoietic progenitors); the in utero HLA-typing; the implication of employing 'blood belonging to a neonate' for a third party; the need to perform a number of investigations both on the CB of the donor and on the mother and the implications that the discovery of disease may have for them, but also the need to establish banks for storing CB, with the accompanying administration and management problems. All these different aspects of UCBT will be discussed in the light of the four fundamental and traditional principles of bioethics, namely autonomy, nonmaleficence, beneficence and justice. PMID:9208108

  12. Apoptosis-induced cell death due to oleanolic acid in HaCaT keratinocyte cells--a proof-of-principle approach for chemopreventive drug development.

    Science.gov (United States)

    George, V Cijo; Kumar, D R Naveen; Suresh, P K; Kumar, R Ashok

    2012-01-01

    Oleanolic acid (OA) is a naturally occurring triterpenoid in food materials and is a component of the leaves and roots of Olea europaea, Viscum album L., Aralia chinensis L. and more than 120 other plant species. There are several reports validating its antitumor activity against different cancer cells apart from its hepatoprotective activity. However, antitumor activity against skin cancer has not been studied well thus far. Hence the present study of effects of OA against HaCaT (immortalized keratinocyte) cells--a cell-based epithelial model system for toxicity/ethnopharmacology-based studies--was conducted. Radical scavenging activity (DPPH·) and FRAP were determined spectrophotometrically. Proliferation was assessed by XTT assay at 24, 48 and 72 hrs with exposure to various concentrations (12.5-200 μM) of OA. Apoptotic induction potential of OA was demonstrated using a cellular DNA fragmentation ELISA method. Morphological studies were also carried out to elucidate its antitumor potential. The results revealed that OA induces apoptosis by altering cellular morphology as well as DNA integrity in HaCaT cells in a dose-dependent manner, with comparatively low cytotoxicity. The moderate toxicity observed in HaCaT cells, with induction of apoptosis, possibly suggests greater involvement of programmed-cell death-mediated mechanisms. We conclude that OA has relatively low toxicity and has the potential to induce apoptosis in HaCaT cells and hence provides a substantial and sound scientific basis for further validation studies. PMID:22901164

  13. Romerrigets historie

    DEFF Research Database (Denmark)

    Christiansen, Erik

    Romerrigets historie fra Roms legendariske grundlæggelse i 753 f.v.t. til Heraklios' tronbestigelse i 610 e.v.t.......Romerrigets historie fra Roms legendariske grundlæggelse i 753 f.v.t. til Heraklios' tronbestigelse i 610 e.v.t....

  14. Intellectual History

    DEFF Research Database (Denmark)

    In the 5 Questions book series, this volume presents a range of leading scholars in Intellectual History and the History of Ideas through their answers to a brief questionnaire. Respondents include Michael Friedman, Jacques le Goff, Hans Ulrich Gumbrecht, Jonathan Israel, Phiip Pettit, John Pocock...

  15. One-deviation principle in coalition formation

    OpenAIRE

    Hannu Vartiainen

    2008-01-01

    We study coalitional one-deviation principle in a framework a la Chwe (1994). The principle requires that an active coalition or any of its subcoalition will not benefit from a single deviation to a strategy that specifies, for each history of coalitional moves, an active coalition and its move. A strategy meeting the one-deviation property is characterized. Moreover, it is shown to exist. Finally, the results are compared to the existing theories of coalitional games.

  16. Dynamical principles in neuroscience

    International Nuclear Information System (INIS)

    Dynamical modeling of neural systems and brain functions has a history of success over the last half century. This includes, for example, the explanation and prediction of some features of neural rhythmic behaviors. Many interesting dynamical models of learning and memory based on physiological experiments have been suggested over the last two decades. Dynamical models even of consciousness now exist. Usually these models and results are based on traditional approaches and paradigms of nonlinear dynamics including dynamical chaos. Neural systems are, however, an unusual subject for nonlinear dynamics for several reasons: (i) Even the simplest neural network, with only a few neurons and synaptic connections, has an enormous number of variables and control parameters. These make neural systems adaptive and flexible, and are critical to their biological function. (ii) In contrast to traditional physical systems described by well-known basic principles, first principles governing the dynamics of neural systems are unknown. (iii) Many different neural systems exhibit similar dynamics despite having different architectures and different levels of complexity. (iv) The network architecture and connection strengths are usually not known in detail and therefore the dynamical analysis must, in some sense, be probabilistic. (v) Since nervous systems are able to organize behavior based on sensory inputs, the dynamical modeling of these systems has to explain the transformation of temporal information into combinatorial or combinatorial-temporal codes, and vice versa, for memory and recognition. In this review these problems are discussed in the context of addressing the stimulating questions: What can neuroscience learn from nonlinear dynamics, and what can nonlinear dynamics learn from neuroscience?

  17. (18)F-FDG PET/CT quantification in head and neck squamous cell cancer: principles, technical issues and clinical applications.

    Science.gov (United States)

    Manca, Gianpiero; Vanzi, Eleonora; Rubello, Domenico; Giammarile, Francesco; Grassetto, Gaia; Wong, Ka Kit; Perkins, Alan C; Colletti, Patrick M; Volterrani, Duccio

    2016-07-01

    (18)F-FDG PET/CT plays a crucial role in the diagnosis and management of patients with head and neck squamous cell cancer (HNSCC). The major clinical applications of this method include diagnosing an unknown primary tumour, identifying regional lymph node involvement and distant metastases, and providing prognostic information. (18)F-FDG PET/CT is also used for precise delineation of the tumour volume for radiation therapy planning and dose painting, and for treatment response monitoring, by detecting residual or recurrent disease. Most of these applications would benefit from a quantitative approach to the disease, but the quantitative capability of (18)F-FDG PET/CT is still underused in HNSCC. Innovations in PET/CT technology promise to overcome the issues that until now have hindered the employment of dynamic procedures in clinical practice and have limited "quantification" to the evaluation of standardized uptake values (SUV), de facto a semiquantitative parameter, the limits of which are well known to the nuclear medicine community. In this paper the principles of quantitative imaging and the related technical issues are reviewed so that professionals involved in HNSCC management can reflect on the advantages of "true" quantification. A discussion is then presented on how semiquantitative information is currently used in clinical (18)F-FDG PET/CT applications in HNSCC, by discussing the improvements that could be obtained with more advanced and "personalized" quantification techniques. PMID:26780912

  18. 18F-FDG PET/CT quantification in head and neck squamous cell cancer: principles, technical issues and clinical applications

    International Nuclear Information System (INIS)

    18F-FDG PET/CT plays a crucial role in the diagnosis and management of patients with head and neck squamous cell cancer (HNSCC). The major clinical applications of this method include diagnosing an unknown primary tumour, identifying regional lymph node involvement and distant metastases, and providing prognostic information. 18F-FDG PET/CT is also used for precise delineation of the tumour volume for radiation therapy planning and dose painting, and for treatment response monitoring, by detecting residual or recurrent disease. Most of these applications would benefit from a quantitative approach to the disease, but the quantitative capability of 18F-FDG PET/CT is still underused in HNSCC. Innovations in PET/CT technology promise to overcome the issues that until now have hindered the employment of dynamic procedures in clinical practice and have limited ''quantification'' to the evaluation of standardized uptake values (SUV), de facto a semiquantitative parameter, the limits of which are well known to the nuclear medicine community. In this paper the principles of quantitative imaging and the related technical issues are reviewed so that professionals involved in HNSCC management can reflect on the advantages of ''true'' quantification. A discussion is then presented on how semiquantitative information is currently used in clinical 18F-FDG PET/CT applications in HNSCC, by discussing the improvements that could be obtained with more advanced and ''personalized'' quantification techniques. (orig.)

  19. Natural history and the Encyclopedie.

    Science.gov (United States)

    Llana, J

    2000-01-01

    The general popularity of natural history in the eighteenth century is mirrored in the frequency and importance of the more than 4,500 articles on natural history in the Encyclopedie. The main contributors to natural history were Daubenton, Diderot, Jaucourt and d'Holbach, but some of the key animating principles derive from Buffon, who wrote nothing specifically for the Encyclopedie. Still, a number of articles reflect his thinking, especially his antipathy toward Linnaeus. There was in principle a natural tie between encyclopedism, with its emphasis on connected knowledge, and the task of natural historians who concentrated on the relationships among living forms. Both the encyclopedists and the natural historians aimed at a sweeping overview of knowledge, and we see that Diderot's discussions of the encyclopedia were apparently informed by his reading of natural history. Most of the articles on natural history drew from traditional sources, but there are differences in emphasis and choice of subject, depending upon the author. Diderot's 300 contributions are often practical, interesting, and depend upon accounts from other parts of the world. Jaucourt, who wrote more articles on natural history than anyone else, followed in his foodsteps. Daubenton's 900 articles reflected a more narrow, professional approach. His contributions concluded for the most part with Volume 8, and Jaucourt carried on almost single-handedly after that. While staking out traditional ground (description, taxonomy) and advancing newer theoretical views linked with Buffon, natural history in the Encyclopedie avoided almost completely the sentimentalism concerning nature that developed after Rousseau. PMID:11624414

  20. Family History

    Science.gov (United States)

    Your family history includes health information about you and your close relatives. Families have many factors in common, including their genes, ... as heart disease, stroke, and cancer. Having a family member with a disease raises your risk, but ...

  1. Using a Replica of Leeuwenhoek's Microscope to Teach the History of Science and to Motivate Students to Discover the Vision and the Contributions of the First Microscopists

    OpenAIRE

    Lenira M.N. Sepel; Loreto, Elgion L. S.; Rocha, João B. T.

    2009-01-01

    The history of science should be incorporated into science teaching as a means of improving learning and also to increase the students' understanding about the nature of science. In biology education, the history of microscopy deserves a special place. The discovery of this instrument not only opened a new and fantastic microworld but also led to the development of one unifying principle of biological sciences (i.e., cell theory). The microscopes of Leeuwenhoek and Hooke opened windows into t...

  2. Principles of Bioenergetics

    CERN Document Server

    Skulachev, Vladimir P; Kasparinsky, Felix O

    2013-01-01

    Principles of Bioenergetics summarizes one of the quickly growing branches of modern biochemistry. Bioenergetics concerns energy transductions occurring in living systems and this book pays special attention to molecular mechanisms of these processes. The main subject of the book is the "energy coupling membrane" which refers to inner membranes of intracellular organelles, for example, mitochondria and chloroplasts. Cellular cytoplasmic membranes where respiratory and photosynthetic energy transducers, as well as ion-transporting ATP-synthases (ATPases) are also part of this membrane. Significant attention is paid to the alternative function of mitochondria as generators of reactive oxygen species (ROS) that mediate programmed death of cells (apoptosis and necrosis) and organisms (phenoptosis). The latter process is considered as a key mechanism of aging which may be suppressed by mitochondria-targeted antioxidants.

  3. Principles of visual attention

    DEFF Research Database (Denmark)

    Bundesen, Claus; Habekost, Thomas

    The nature of attention is one of the oldest and most central problems in psychology. A huge amount of research has been produced on this subject in the last half century, especially on attention in the visual modality, but a general explanation has remained elusive. Many still view attention...... mechanisms are described in a set of simple equations, which allow TVA to mathematically model a large number of classical results in the attention literature. The theory explains psychological and neuroscientific findings by the same equations; TVA is a complete theory of visual attention, linking mind and...... brain. Aimed at advanced students and professional researchers, Principles of Visual Attention contains a detailed review of the most important research done on attention in vision, spanning cognitive psychology, brain imaging, patient studies, and recordings from single cells in the visual cortex. The...

  4. {sup 18}F-FDG PET/CT quantification in head and neck squamous cell cancer: principles, technical issues and clinical applications

    Energy Technology Data Exchange (ETDEWEB)

    Manca, Gianpiero; Volterrani, Duccio [University Hospital of Pisa, Regional Center of Nuclear Medicine, Pisa (Italy); Vanzi, Eleonora [University Hospital of Siena, Service of Medical Physics, Siena (Italy); Rubello, Domenico; Grassetto, Gaia [Santa Maria della Misericordia Rovigo Hospital, Department of Nuclear Medicine, Rovigo (Italy); Giammarile, Francesco [Faculte Charles Merieux, Medecine Nucleaire, Centre Hospitalier and Biophysique, Lyon (France); Wong, Ka Kit [University of Michigan Hospital, Nuclear Medicine/Radiology Department, Ann Arbor, MI (United States); Nuclear Medicine Service, Department of Veterans Affairs Health System, Ann Arbor, MI (United States); Perkins, Alan C. [University of Nottingham, Department of Radiological Sciences, School of Medicine, Nottingham (United Kingdom); Colletti, Patrick M. [Southern University of California, Department of Radiology, Los Angeles, CA (United States)

    2016-07-15

    {sup 18}F-FDG PET/CT plays a crucial role in the diagnosis and management of patients with head and neck squamous cell cancer (HNSCC). The major clinical applications of this method include diagnosing an unknown primary tumour, identifying regional lymph node involvement and distant metastases, and providing prognostic information. {sup 18}F-FDG PET/CT is also used for precise delineation of the tumour volume for radiation therapy planning and dose painting, and for treatment response monitoring, by detecting residual or recurrent disease. Most of these applications would benefit from a quantitative approach to the disease, but the quantitative capability of {sup 18}F-FDG PET/CT is still underused in HNSCC. Innovations in PET/CT technology promise to overcome the issues that until now have hindered the employment of dynamic procedures in clinical practice and have limited ''quantification'' to the evaluation of standardized uptake values (SUV), de facto a semiquantitative parameter, the limits of which are well known to the nuclear medicine community. In this paper the principles of quantitative imaging and the related technical issues are reviewed so that professionals involved in HNSCC management can reflect on the advantages of ''true'' quantification. A discussion is then presented on how semiquantitative information is currently used in clinical {sup 18}F-FDG PET/CT applications in HNSCC, by discussing the improvements that could be obtained with more advanced and ''personalized'' quantification techniques. (orig.)

  5. Hate Speech: A Call to Principles.

    Science.gov (United States)

    Klepper, William M.; Bakken, Timothy

    1997-01-01

    Reviews the history of First Amendment rulings as they relate to speech codes and of other regulations directed at the content of speech. A case study, based on an experience at Trenton State College, details the legal constraints, principles, and practices that Student Affairs administrators should be aware of regarding such situations.…

  6. Bioclimatic underground architecture: Development and principles

    OpenAIRE

    Stojić Jasmina; Stanković Danica

    2009-01-01

    The principal idea of paper lies in analyzing contemporary architectural challenges, concerning climate changes, global warming, renewable energy deficiency and population growth. The relevant examples and principles of sustainable and selfsustainable architecture development throughout history are presented. Underground structures as passive solar systems, vegetation used as insulation, ventilation and isolation are given as one of possible solutions for this global phenomenon. By studying t...

  7. Análise de periódicos na história da educação: princípios e procedimentos Analysis of journals in the history of education: principles and procedures

    Directory of Open Access Journals (Sweden)

    Fabiana Silva Fernandes

    2012-08-01

    Full Text Available O trabalho discorre sobre a elaboração da Base de Dados do "Boletim Interno da Divisão de Educação, Assistência e Recreio", da Secretaria de Educação e Cultura do Município de São Paulo, publicação mensal que circulou nos Parques Infantis paulistanos no período de 1947 a 1957. A criação da base justifica-se pela necessidade de se sistematizarem informações sobre a estrutura e a organização do Boletim Interno e identificar tendências educacionais e temas enfocados. Tornou-se orientação o princípio de que a definição dos campos de registro não deve ocorrer, a priori, sem um exame prévio da publicação. Considera-se a base como um primeiro processo de análise que, para prover elementos para a pesquisa, precisa ser composta por campos analíticos adequados às especificidades da publicação, ultrapassando a formalidade de registros.The study describes the setting up of a database for the "Internal Bulletin of the Education, Assistance and Recreation Division - Boletim Interno da Divisão de Educação, Assistência e Recreio" of the São Paulo Municipal Secretariat for Education and Culture, a monthly publication that circulated among kindergartens in the city of São Paulo from 1947 to 1957. We justify the setting-up of the database because of the need to systematize the information on the structure and organization of the Internal Bulletin and identify educational trends and topics that were focused on. The guiding principle was that recording fields should not be defined, a priori, without prior examination of the publication. The database is deemed to be a first analytical process, which in order to provide information to the study, needs to be composed of analytical fields that are suitable to the specificities of the publication, going beyond the formality of records.

  8. Linjefaget historie

    DEFF Research Database (Denmark)

    Rasch-Christensen, Andreas

    Afhandlingen er en undersøgelse af linjefaget historie ved læreruddannelsen. Med fokus på subjektperspektivet peger afhandlingen på en række afgørende udviklingsperspektiver for læreruddannelsen, uddannelsen af historielærere og folkeskolens historieundervisning.......Afhandlingen er en undersøgelse af linjefaget historie ved læreruddannelsen. Med fokus på subjektperspektivet peger afhandlingen på en række afgørende udviklingsperspektiver for læreruddannelsen, uddannelsen af historielærere og folkeskolens historieundervisning....

  9. Matematikkens historie

    DEFF Research Database (Denmark)

    Hansen, Vagn Lundsgaard

    2009-01-01

    Matematikkens historie i syv kapitler: 1. Matematik i støbeskeen; 2. Matematikkens græske arv; 3. Den gyldne tidsalder for hinduer og arabere; 4. Matematik i Kina; 5. Renæssancens matematik; 6. Regning med infinitesimaler ser dagens lys; 7. Matematik i det tyvende århundrede.......Matematikkens historie i syv kapitler: 1. Matematik i støbeskeen; 2. Matematikkens græske arv; 3. Den gyldne tidsalder for hinduer og arabere; 4. Matematik i Kina; 5. Renæssancens matematik; 6. Regning med infinitesimaler ser dagens lys; 7. Matematik i det tyvende århundrede....

  10. Environmental history

    DEFF Research Database (Denmark)

    Pawson, Eric; Christensen, Andreas Aagaard

    2016-01-01

    Environmental history is an interdisciplinary pursuit that has developed as a form of conscience to counter an increasingly powerful, forward-looking liberal theory of the environment. It deals with the relations between environmental ideas and materialities, from the work of the geographers George...... risks”. These are exposed by environmental history’s focus on long-run analysis and its narrative form that identifies the stories that we tell ourselves about nature. How a better understanding of past environmental transformations helps to analyse society and agency, and what this can mean...... for solutions and policies, is the agenda for an engaged environmental history from now on....

  11. Study of wurtzite and zincblende GaN/InN based solar cells alloys: First-principles investigation within the improved modified Becke-Johnson potential

    KAUST Repository

    Ul Haq, Bakhtiar

    2014-09-01

    Wurtzite GaInN alloys with flexible energy gaps are pronounced for their potential applications in optoelectronics and solar cell technology. Recently the unwanted built-in fields caused by spontaneous polarization and piezoelectric effects in wurtzite (WZ) GaInN, has turned the focus towards zinc-blende (ZB) GaInN alloys. To comprehend merits and demerits of GaInN alloys in WZ and ZB structures, we performed a comparative study of the structural, electronic and optical properties of Ga1-xInxN alloys with different In concentration using first-principles methodology with density function theory with generalized gradient approximations (GGA) and modified Becke-Johnson (mBJ) potential. Investigations pertaining to total energy of GaInN for the both phases, demonstrate a marginal difference, reflecting nearly equivalent stability of the ZB-GaInN to WZ-GaInN. The larger ionic radii of indium (In), result in larger values of lattice parameters of Ga1-xInxN with higher In concentration. For In deficient Ga1-xInxN, at first, the formation enthalpies increase rapidly as the In content approaches to 45% in WZ and 47% in ZB, and then decreases with the further increase in In concentration. ZB-Ga1-xInxN alloys exhibit comparatively narrower energy gaps than WZ, and get smaller with increase in In contents. The smaller values of effective masses of free carriers, in WZ phase, than ZB phase, reflect higher carrier mobility and electrical conductivity of WZ-Ga1-xInxN. Moreover wide energy gap of WZ-Ga1-xInxN results in large values of the absorption coefficients comparatively and smaller static refractive indices compared to ZB-Ga1-xInxN. Comparable electronic and optical characteristics of the ZB-Ga1-xInxN to WZ-Ga1-xInxN endorses it a material of choice for optoelectronics and solar cell applications besides the WZ-Ga1-xInxN. © 2014 Elsevier Ltd.

  12. Chemical Principls Exemplified

    Science.gov (United States)

    Plumb, Robert C.

    1973-01-01

    Two topics are discussed: (1) Stomach Upset Caused by Aspirin, illustrating principles of acid-base equilibrium and solubility; (2) Physical Chemistry of the Drinking Duck, illustrating principles of phase equilibria and thermodynamics. (DF)

  13. Principles of project management

    Science.gov (United States)

    1982-01-01

    The basic principles of project management as practiced by NASA management personnel are presented. These principles are given as ground rules and guidelines to be used in the performance of research, development, construction or operational assignments.

  14. Acupuntura: histórico, bases teóricas e sua aplicação em Medicina Veterinária Acupuncture: history, basic principles and its use in Veterinary Medicine

    Directory of Open Access Journals (Sweden)

    Márcia Valéria Rizzo Scognamillo-Szabó

    2010-02-01

    Full Text Available A acupuntura (AP é uma técnica terapêutica empírica desenvolvida em uma cultura oriental e que utiliza pensamento mágico (linguagem pré-científica em seu raciocínio. É uma terapia reflexa que utiliza a estimulação de pontos específicos do corpo com objetivo de atingir um efeito terapêutico ou homeostático. A AP preconiza que a saúde é dependente das funções psico-neuro-endócrinas, sob influência do código genético e de fatores extrínsecos como nutrição, hábitos de vida, clima, qualidade do ambiente, entre outros. O presente artigo faz uma breve revisão sobre a filosofia da AP, seus marcos históricos na China e no Ocidente, a história da AP veterinária no Brasil e no mundo. Também aborda a prática da AP, incluindo as formas de diagnóstico, a definição do protocolo de tratamento, os métodos de estimulação dos pontos, o agulhamento de animais, suas indicações, contra-indicações e reações adversas.Acupuncture (AP is an ancient empirical Eastern therapeutical technique that uses magical though (pre-scientific language in this domain. Reflex therapy that uses the stimulation of specific points of the body to achieve a therapeutic or homeostatic effect. According to AP, health depends on psico-neuro-endocrine functions under the influence of the genetic code and extrinsic factors like nutrition, daily habits, weather, environment and others. The present article is a brief review on the AP philosophy, its historical marks in East and West, the veterinary AP history in Brazil and abroad. It also summarizes AP practice, including diagnosis, treatment protocols, the needling of animals, its indications, non-indications and adverse effects.

  15. Polluter Pays Principle

    OpenAIRE

    Samuel, Asumadu-Sarkodie; Aigul, Myrzabekova

    2015-01-01

    A group presenation to Identify and outline the main features of the polluter pays principle. Show how polluter pays principle (PPP) may be the most effective instrument for ‘greening’ (rejuvenating) the current global economy, and identify any limitations of the polluter pays principle (PPP).

  16. Monoclonal B-cell lymphocytosis and early-stage chronic lymphocytic leukemia: diagnosis, natural history, and risk stratification

    OpenAIRE

    Strati, Paolo; Shanafelt, Tait D.

    2015-01-01

    Monoclonal B lymphocytosis (MBL) is defined as the presence of a clonal B-cell population in the peripheral blood with fewer than 5 × 109/L B-cells and no other signs of a lymphoproliferative disorder. The majority of cases of MBL have the immunophenotype of chronic lymphocytic leukemia (CLL). MBL can be categorized as either low count or high count based on whether the B-cell count is above or below 0.5 × 109/L. Low-count MBL can be detected in ∼5% of adults over the age of 40 years when ass...

  17. Large area multicrystalline silicon solar cells in high volume production environment - history, status, new processes, technology transfer issues

    International Nuclear Information System (INIS)

    Cast multicrystalline silicon (mc-Si) solar cell technology, accounted for nearly 41% of all the PV modules manufactures worldwide in 2000. Since 1995 the use of cast mc-Si as a substrate has increased every year and that increase is expected to accelerate in the coming years as the PV market grows further. This impressive growth has been enabled by several factors - wafer suppliers, improvements in casting technology, sawing technology and cell process technology. In this paper the enabling factors will be discussed. The new processes used to enhance the efficiency of the cast multicrystalline silicon solar cells and the criteria for technology transfer will also be discussed. (author)

  18. Multiple basal cell carcinomas arising in a port-wine stain with a remote history of therapeutic irradiation

    International Nuclear Information System (INIS)

    The coexistence of a basal cell carcinoma and a port-wine stain is a very rare condition that may be associated with previous treatments. We present a case of multiple basal cell carcinomas developing within the boundaries of a port-wine stain, which had been treated with a tholium X and argon laser. Our case suggests that port-wine stains which were previously treated with irradiation or argon laser should be examined carefully and regularly by both physician and patient, because they may hide basal cell carcinomas. (author)

  19. Analytical Research to Determine the effects of the Components of ONGABO on the Viability of HepG2 Cancer Cells by Using the Sovereign, Minister, Assistant and Courier Principle (君臣佐使論

    Directory of Open Access Journals (Sweden)

    Shin Jeong-Hun

    2012-12-01

    Full Text Available Objectives: This study used the basic principle of Oriental medicine, the sovereign, minister, assistant and courier principle (君臣佐使論 to investigate the effects of the component of ONGABO, which is composed of Ginseng Radix (Red Ginseng, Angelica Gigantis Radix, Schisandrae Fructus, Cuscuta Semen and Curcumae tuber on the viability of HepG2 cells. Methods: Single and mixed extracts of the component of ONGABO were prepared by lypohilizing powder of Red Ginseng (6-year root from Kanghwa, Angelica Gigantis Radix, Schisandrae Fructus, Cuscuta Semen, Curcumae Tuber (from Omniherb Co., Ltd., Korea at the laboratory of herbal medicine in Woosuk University and were eluted after being macerated with 100% ethanol for three days. The cell viability of HepG2 was determined by using an absorptiometric analysis with PrestoBlue (Invitrogen reagent after the plate had been incubated for 48 hours. All of the experiments were repeated three times to obtain the average value and standard deviation. The statistical analysis was done and the correlation factor was obtained by using Microsoft Office Excel 2007 and Origin 6.0 software. Results: Although Ginseng Radix (Red Ginseng and Schisandrae Fructus did not enhance the viability of HepG2 cells, they were shown to provide protection of those cells. On the other hand, Angelica Gigantis Radix decreased the viability of HepG2 cells significantly, Cuscuta Semen and Curcumae Tuber had a small or no effect on the viability of HepG2 cells. Conclusions: In the sovereign, minister, assistant and courier principle (君臣佐使論, Ginseng Radix (Red Ginseng corresponds to the sovereign component because it provides cell protection effects, Angelica Gigantis Radix corresponds to minister medicinal because it kills cells, Schisandrae Fructus corresponds to the assistant medicinal to help red ginseng having cell protect effects. Cuscuta Semen and Curcumae Tuber correspond to the courier medicinal having no effect in

  20. Potted history

    OpenAIRE

    Dijk, T. van

    2010-01-01

    The Jordan Valley was once populated by a people, now almost forgotten by historians, with whom the pharaoh of Egypt sought favour. That is the conclusion reached by Niels Groot, the first researcher to take a PhD at the Delft-Leiden Centre for Archaeology, Art History and Science.

  1. Family History

    Science.gov (United States)

    ... risky behaviors (such as smoking) and increasing healthy behaviors (such as regular exercise). Learn more about heart attacts. Q: How can knowing my family health history help lower my risk of disease? A: You ... you can change behaviors that affect your health, such as smoking, inactivity ...

  2. Business History

    DEFF Research Database (Denmark)

    Hansen, Per H.

    2012-01-01

    This article argues that a cultural and narrative perspective can enrich the business history field, encourage new and different questions and answers, and provide new ways of thinking about methods and empirical material. It discusses what culture is and how it relates to narratives. Taking...

  3. Principles for system level electrochemistry

    Science.gov (United States)

    Thaller, L. H.

    1986-01-01

    The higher power and higher voltage levels anticipated for future space missions have required a careful review of the techniques currently in use to preclude battery problems that are related to the dispersion characteristics of the individual cells. Not only are the out-of-balance problems accentuated in these larger systems, but the thermal management considerations also require a greater degree of accurate design. Newer concepts which employ active cooling techniques are being developed which permit higher rates of discharge and tighter packing densities for the electrochemical components. This paper will put forward six semi-independent principles relating to battery systems. These principles will progressively address cell, battery and finally system related aspects of large electrochemical storage systems.

  4. Sommerferiens historie

    DEFF Research Database (Denmark)

    Lützen, Karin

    2011-01-01

    Summer holiday is a pleasure which did not become available to many people until the 20th Century. The article describes the early mountain rambles of the bourgeoisie and their holidays in seaside boarding houses. Outdoor pursuits and stays in boarding houses at bathing resorts also became favour...... pattern. Finally, the history of the special holiday camps is told, which were established by American Jews because they were excluded from many hotels....

  5. Time, history and international law

    CERN Document Server

    Craven, Matthew; Vogiatzi, Maria

    2006-01-01

    This book examines theoretical and practical issues concerning the relationship between international law, time and history. Problems relating to time and history are ever-present in the work of international lawyers, whether understood in terms of the role of historic practice in the doctrine of sources, the application of the principle of inter-temporal law in dispute settlement, or in gaining a coherent insight into the role that was played by international law in past events. But very little has been written about the various different ways in which international lawyers approach or unders

  6. Publication Principles and Guidelines

    OpenAIRE

    KARACA, Ragıp Kutay

    2015-01-01

    Sciences, Political Science and International Relations, Law, History of Art, Archaeology, Communication Sciences, Linguistics, Fine Arts, History, Sociology, Psychology, Turkish Language and Literature, Philosophy, Geography, Security and Education Sciences

  7. Principles of radiation therapy

    International Nuclear Information System (INIS)

    Radiation oncology now represents the integration of knowledge obtained over an 80-year period from the physics and biology laboratories and the medical clinic. Such integration is recent; until the supervoltage era following World War II, the chief developments in these three areas for the most part were realized independently. The physics and engineering laboratories have now developed a dependable family of sources of ionizing radiations that can be precisely directed at tumor volumes at various depths within the body. The biology laboratory has provided the basic scientific support underlying the intensive clinical experience and currently is suggesting ways of using ionizing radiations more effectively, such as modified fractionation schedules relating to cell cycle kinetics and the use of drugs and chemicals as modifiers of radiation response and normal tissue reaction. The radiation therapy clinic has provided the patient stratum on which the acute and chronic effects of irradiation have been assessed, and the patterns of treatment success and failure identified. The radiation therapist has shared with the surgeon and medical oncologist the responsibility for clarifying the natural history of a large number of human neoplasms, and through such clarifications, has developed more effective treatment strategies. Several examples of this include the improved results in the treatment of Hodgkin's disease, squamous cell carcinoma of the cervix, seminoma, and epithelial neoplasms of the upper aerodigestive tract

  8. Symposium on the principles of radiation research applied to environmental agents. The concept of drug dose for in vitro studies with chemotherapeutic agents. [Treatment of rat 9L brain tumor cells in vitro with BCNU and CCNU

    Energy Technology Data Exchange (ETDEWEB)

    Wheeler, K.T. (Univ. of Rochester, NY); Levin, V.A.; Deen, D.F.

    1978-12-01

    Determination of the radiation dose delivered to or received by tissue culture cells during irradiation in vitro is relatively straightforward compared to determination of the drug dose delivered to or received by these same cells when treated with chemical agents. After defining drug exposure dose and drug absorbed dose, this paper uses pharmacokinetic and cell survival data collected from experiments where rat 9L brain tumor cells were treated in culture with BCNU and CCNU to illustrate the problems and principles involved in adequately assessing the appropriate drug dose in such experiments. Practical solutions to these experimental problems are presented for many of those situations where pharmacokinetic data is either unobtainable or unavailable. It is hoped that the concepts illustrated here will provide a more uniform framework for performing interpretable in vitro drug experiments.

  9. Pseudomonas fluorescens HK44: Lessons Learned from a Model Whole-Cell Bioreporter with a Broad Application History

    Directory of Open Access Journals (Sweden)

    Gary S. Sayler

    2012-02-01

    Full Text Available Initially described in 1990, Pseudomonas fluorescens HK44 served as the first whole-cell bioreporter genetically endowed with a bioluminescent (luxCDABE phenotype directly linked to a catabolic (naphthalene degradative pathway. HK44 was the first genetically engineered microorganism to be released in the field to monitor bioremediation potential. Subsequent to that release, strain HK44 had been introduced into other solids (soils, sands, liquid (water, wastewater, and volatile environments. In these matrices, it has functioned as one of the best characterized chemically-responsive environmental bioreporters and as a model organism for understanding bacterial colonization and transport, cell immobilization strategies, and the kinetics of cellular bioluminescent emission. This review summarizes the characteristics of P. fluorescens HK44 and the extensive range of its applications with special focus on the monitoring of bioremediation processes and biosensing of environmental pollution.

  10. Woman with Sickle Cell Disease with Current Sigmoid Sinus Thrombosis and History of Inadequate Warfarin Use during a Past Thrombotic Event

    Science.gov (United States)

    Çelikbilek, Asuman; Çelikbilek, Mehmet; Bozkurt, Alper; Karakurum Göksel, Başak; Tan, Meliha; Özdoğu, Hakan

    2009-01-01

    We report a 20-year-old woman with sickle cell disease (SCD) who presented with a severe pulsating headache, nausea, and vomiting. Her history was significant for a past thrombotic event during which she had not used anticoagulation therapy as prescribed. Her mental status was mildly confused. On funduscopic examination, papilledema and retinal hemorrhages were found. Results of a computed tomogram were normal. A lumbar puncture demonstrated increased intracranial pressure (60 cm H2O). Magnetic resonance venography demonstrated a right sigmoid sinus thrombosis. Although SCD has been reported as a cause of thrombotic dural venous sinus events, this case increases the knowledge about neurological complications of SCD. The patient was treated with low molecular weight heparin, blood transfusions, acetazolamide, and methylprednisolone, and her symptoms and signs resolved. PMID:20847926

  11. The potential of molecular markers to improve interventions through the natural history of oesophageal squamous cell carcinoma

    OpenAIRE

    2013-01-01

    EC (oesophageal cancer) is one of the ten most frequent and fatal tumours worldwide and ESCC (oesophageal squamous cell carcinoma) accounts for about 80% of the cases. The first symptoms of ESCC arise late during the progression of the disease and, therefore, the diagnosis is usually done in advanced stages. This leads to an inefficient treatment and consequently to a poor prognosis. Thus, a comprehensive knowledge of ESCC biology is of major importance to identify risk factors, especially in...

  12. Pantoea species sepsis associated with sickle cell crisis in a pregnant woman with a history of pica

    OpenAIRE

    Achkar, Morhaf Al; Rogers, Jordan S.; Muszynski, Michael J.

    2012-01-01

    Summary Background: Bacteria in the Pantoea genus are plant and soil associated Gram-negative rods described as nosocomial pathogens and as rare causes of community-acquired infections. The latter have been classically associated with gardening and plant thorn injuries and immunocompromised states are additional risk factors. We report a patient with pica and geophagia, Pantoea sepsis, and sickle cell crisis, associations not previously described. Case Report: A 23-year-old pregnant female pr...

  13. Biomechanics principles and practices

    CERN Document Server

    Peterson, Donald R

    2014-01-01

    Presents Current Principles and ApplicationsBiomedical engineering is considered to be the most expansive of all the engineering sciences. Its function involves the direct combination of core engineering sciences as well as knowledge of nonengineering disciplines such as biology and medicine. Drawing on material from the biomechanics section of The Biomedical Engineering Handbook, Fourth Edition and utilizing the expert knowledge of respected published scientists in the application and research of biomechanics, Biomechanics: Principles and Practices discusses the latest principles and applicat

  14. Principles of Superconductivity

    OpenAIRE

    Mourachkine, A.

    2004-01-01

    The purpose of this chapter is to discuss the main principles of superconductivity as a phenomenon, valid for every superconductor independently of its characteristic properties and material. The underlying mechanisms of superconductivity can be different for various materials, but certain principles must be satisfied. The chapter introduces four principles of superconductivity. (The chapter is slightly nodified from the original one in order to be self-contained.)

  15. Fusion research principles

    CERN Document Server

    Dolan, Thomas James

    2013-01-01

    Fusion Research, Volume I: Principles provides a general description of the methods and problems of fusion research. The book contains three main parts: Principles, Experiments, and Technology. The Principles part describes the conditions necessary for a fusion reaction, as well as the fundamentals of plasma confinement, heating, and diagnostics. The Experiments part details about forty plasma confinement schemes and experiments. The last part explores various engineering problems associated with reactor design, vacuum and magnet systems, materials, plasma purity, fueling, blankets, neutronics

  16. Uncovering History for Future History Teachers

    Science.gov (United States)

    Fischer, Fritz

    2010-01-01

    The art of history teaching is at a crossroads. Recent scholarship focuses on the need to change the teaching of history so students can better learn history, and insists that history teachers must move beyond traditional structures and methods of teaching in order to improve their students' abilities to think with history. This article presents…

  17. Database principles programming performance

    CERN Document Server

    O'Neil, Patrick

    2014-01-01

    Database: Principles Programming Performance provides an introduction to the fundamental principles of database systems. This book focuses on database programming and the relationships between principles, programming, and performance.Organized into 10 chapters, this book begins with an overview of database design principles and presents a comprehensive introduction to the concepts used by a DBA. This text then provides grounding in many abstract concepts of the relational model. Other chapters introduce SQL, describing its capabilities and covering the statements and functions of the programmi

  18. Ildens historier

    DEFF Research Database (Denmark)

    Lassen, Henrik Roesgaard

    In December 2012 a manuscript entitled "Tællelyset" ['The Tallow Candle'] was discovered in an archive. The story was subsequently presented to the world as Hans Christian Andersen's first fairy tale and rather bombastically celebrated as such. In this book it is demonstrated that the text cannot...... have been written by Andersen. In several chapters the curiously forgotten history of fire-lighting technology is outlined, and it is demonstrated that "Tællelyset" is written by a person with a modern perspective on how to light a candle - among other things. The central argument in the book springs...

  19. p53 mutations in non-small-cell lung cancers occurring in individuals without a past history of active smoking.

    OpenAIRE

    Takagi, Y.; Osada, H.; Kuroishi, T; Mitsudomi, T.; Kondo, M.; Niimi, T.; Saji, S; Gazdar, A. F.; Minna, J D; Takahashi, T.

    1998-01-01

    Accumulating evidence suggests that the p53 gene is a good target for molecular epidemiological studies. We previously reported an association between the presence of p53 mutations and lifetime cigarette consumption. Although over 675 p53 mutations have been reported in lung cancers in the literature thus far, very little is known about the nature of such changes in lung cancers in the absence of a smoking background. In the present study, we therefore analysed 69 non-small-cell lung cancer s...

  20. Effect of Cu doping on Ba0.5Sr0.5Fe1-xCuxO3-δ perovskites for solid oxide fuel cells: A first-principles study

    Science.gov (United States)

    Vázquez, Santiago; Suescun, Leopoldo; Faccio, Ricardo

    2016-04-01

    Nowadays a rational design of solid oxide fuel cells (SOFCs) cathodes is possible thanks to first-principles calculations based on density functional theory (DFT). We study the effect of Cu-doping in the bulk properties for the perovskite Ba0.5Sr0.5Fe1-xCuxO3-δ (with x = 0, 0.25 and 0.50) and correlate the results with previous experimental characterization. Bulk properties such as geometric structure, charge analysis, thermodynamic stability, vacancy formation energy, oxygen diffusion and electronic structure where studied in detail to provide an explanation of the oxygen reduction reaction (ORR) activity enhancement with Cu-doping. The results obtained here, using GGA+U, demonstrate the first-principles approach gives useful information that allows the prediction and explanation of experimental characterizations.

  1. Hamilton's Principle for Beginners

    Science.gov (United States)

    Brun, J. L.

    2007-01-01

    I find that students have difficulty with Hamilton's principle, at least the first time they come into contact with it, and therefore it is worth designing some examples to help students grasp its complex meaning. This paper supplies the simplest example to consolidate the learning of the quoted principle: that of a free particle moving along a…

  2. Principled Grammar Teaching

    Science.gov (United States)

    Batstone, Rob; Ellis, Rod

    2009-01-01

    A key aspect of the acquisition of grammar for second language learners involves learning how to make appropriate connections between grammatical forms and the meanings which they typically signal. We argue that learning form/function mappings involves three interrelated principles. The first is the Given-to-New Principle, where existing world…

  3. The Principles of Leadership.

    Science.gov (United States)

    Burns, Gerald P.

    The primary but not exclusive concern in this monograph is the principles and qualities of dynamic leaders of people rather than of ideas or cultural and artistic pursuits. Theories of leadership in the past, present, and future are discussed, as are the principles, rewards, exercise, and philosophy of leadership. A bibliography is included. (MSE)

  4. Basic principle of superconductivity

    OpenAIRE

    De Cao, Tian

    2007-01-01

    The basic principle of superconductivity is suggested in this paper. There have been two vital wrong suggestions on the basic principle, one is the relation between superconductivity and the Bose-Einstein condensation (BEC), and another is the relation between superconductivity and pseudogap.

  5. Great Principles of Computing

    OpenAIRE

    Denning, Peter J.

    2008-01-01

    The Great Principles of Computing is a framework for understanding computing as a field of science. The website ...April 2008 (Rev. 8/31/08) The Great Principles of Computing is a framework for understanding computing as a field of science.

  6. Guiding Principles for Evaluators.

    Science.gov (United States)

    Shadish, William R., Ed.; And Others

    1995-01-01

    The 12 articles (including an index) of this theme issue are devoted to documenting and critiquing the American Evaluation Association's "Guiding Principles for Evaluators," a code of ethics and standards. The development of these principles is traced, and their strengths and weaknesses are analyzed at general and specific levels. (SLD)

  7. A new computing principle

    International Nuclear Information System (INIS)

    In 1954 while reviewing the theory of communication and cybernetics the late Professor Dennis Gabor presented a new mathematical principle for the design of advanced computers. During our work on these computers it was found that the Gabor formulation can be further advanced to include more recent developments in Lie algebras and geometric probability, giving rise to a new computing principle

  8. The principle of proportionateness

    International Nuclear Information System (INIS)

    The principle of proportionateness is a subject that has been dealt with in numerous court decisions and in a great number of scientific studies, some of them of a very fundamental nature. Still, this principle keeps posing problems both with regard to interpretation and practical application. The study in hand is an attempt towards finding outline solutions for principal problems by first collecting, analysing and harmonising the terminology used, in order to explain the applicability of the principle in the field of legislation, administration, and adjudication. Atomic energy law is then chosen as a subject field of law well suited to demonstrating the great significance of the principle, as decisions taken in this field frequently are governed by this principle (e.g. definition of 'remaining risk' and limits of provisions for damage prevention). (orig.)

  9. Principlism and communitarianism.

    Science.gov (United States)

    Callahan, D

    2003-10-01

    The decline in the interest in ethical theory is first outlined, as a background to the author's discussion of principlism. The author's own stance, that of a communitarian philosopher, is then described, before the subject of principlism itself is addressed. Two problems stand in the way of the author's embracing principlism: its individualistic bias and its capacity to block substantive ethical inquiry. The more serious problem the author finds to be its blocking function. Discussing the four scenarios the author finds that the utility of principlism is shown in the two scenarios about Jehovah's Witnesses but that when it comes to selling kidneys for transplantation and germline enhancement, principlism is of little help. PMID:14519838

  10. Variational principles in physics

    CERN Document Server

    Basdevant, Jean-Louis

    2007-01-01

    Optimization under constraints is an essential part of everyday life. Indeed, we routinely solve problems by striking a balance between contradictory interests, individual desires and material contingencies. This notion of equilibrium was dear to thinkers of the enlightenment, as illustrated by Montesquieu’s famous formulation: "In all magistracies, the greatness of the power must be compensated by the brevity of the duration." Astonishingly, natural laws are guided by a similar principle. Variational principles have proven to be surprisingly fertile. For example, Fermat used variational methods to demonstrate that light follows the fastest route from one point to another, an idea which came to be known as Fermat’s principle, a cornerstone of geometrical optics. Variational Principles in Physics explains variational principles and charts their use throughout modern physics. The heart of the book is devoted to the analytical mechanics of Lagrange and Hamilton, the basic tools of any physicist. Prof. Basdev...

  11. FIGO Stage IIIB squamous cell carcinoma of the uterine cervix: natural history, treatment results, and prognostic factors

    International Nuclear Information System (INIS)

    Purpose: To define patient, tumor, and treatment factors that influence the outcome of patients with FIGO Stage IIIB squamous cell carcinoma of the intact uterine cervix. Materials and Methods: The hospital and radiotherapy records of 1007 consecutive patients treated between 1960 and 1989 for FIGO Stage IIIB squamous cell carcinoma of the intact uterine cervix were reviewed retrospectively. All patients were treated with radiation therapy (RT) either with curative intent (903 patients) or to palliate symptoms (104 patients). Patients who were selected for palliative treatment usually had a combination of adverse characteristics including massive tumor with bilateral pelvic wall fixation, hydronephrosis, bulky adenopathy, pathologic evidence of extrapelvic disease, and poor performance status. 64 (7%) of 903 patients failed to complete planned curative RT either because of progressive disease, complications, or poor compliance. Of 903 patients treated with curative intent, 319 (35%) were treated with external beam radiotherapy (EBRT) alone and 586 (65%) were treated with a combination of EBRT and intracavitary irradiation (ICRT). EBRT was usually delivered using 18-25 MV photons and ICRT was administered with Fletcher-Suit-Delclos applicators. Treatment philosophies evolved during the study period with greater emphasis placed on EBRT between 1966 and 1979 (52% treated with EBRT alone) compared with the other study years (15% treated with EBRT alone). 206 patients received investigational treatments including neutrons (69 pts), hyperbaric oxygen (66 pts), concurrent chemotherapy (29 pts), or neoadjuvant chemotherapy (42 pts). 875 patients have been followed until death. Median follow up for surviving patients is 171 months with only 9 surviving patients followed for 10%, or hgb < 10 gm% before treatment or at any time during radiotherapy. DSS was significantly better for patients whose treatment included ICRT (43% vs 21%; P< 0.0001). Also, patients who received

  12. International institute for collaborative cell biology and biochemistry--history and memoirs from an international network for biological sciences.

    Science.gov (United States)

    Cameron, L C

    2013-01-01

    I was invited to write this essay on the occasion of my selection as the recipient of the 2012 Bruce Alberts Award for Excellence in Science Education from the American Society for Cell Biology (ASCB). Receiving this award is an enormous honor. When I read the email announcement for the first time, it was more than a surprise to me, it was unbelievable. I joined ASCB in 1996, when I presented a poster and received a travel award. Since then, I have attended almost every ASCB meeting. I will try to use this essay to share with readers one of the best experiences in my life. Because this is an essay, I take the liberty of mixing some of my thoughts with data in a way that it not usual in scientific writing. I hope that this sacrifice of the format will achieve the goal of conveying what I have learned over the past 20 yr, during which time a group of colleagues and friends created a nexus of knowledge and wisdom. We have worked together to build a network capable of sharing and inspiring science all over the world. PMID:24006381

  13. Beta-cell dysfunction is the primary contributor to the early postpartum diabetes among Chinese women with history of gestational diabetes mellitus

    Institute of Scientific and Technical Information of China (English)

    CAO Xiao-pei; XIAO Hai-peng; CHEN Song-jin; ZHAN Yan-feng; XIU Ling-ling; WANG Zi-lian

    2008-01-01

    Background Women with a history of gestational diabetes mellitus(GDM)are at higher risk of future development of diabetes. This study investigated the risk factors associated with early postpartum abnormal glucose regulation (AGR) among Chinese women with a history of GDM. Methods A total of 186 women with a history of GDM were screened for early postpartum AGR at 6-8 weeks after delivery. Those with AGR were given lifestyle intervention therapy and reevaluated in 6-12 months. The demographic, anthropometric, prenatal and delivery data were recorded. The plasma high-sensitivity C-reactive protein (HsCRP)and lipid concentration were measured, and insulin secretion were analyzed. Insulinogenic index △ins30'/△BG30', the homeostasis model assessment index(HOMA)-B, and HOMA-IR were calculated. Multiple regression analysis was performed to identify the risk factors. Results of the GDM women 28. O%(52/186)had AGR at 6-8 weeks after delivery;45. 2% (17/40) of these AGR women reminded abnormal after 6-12 month lifestyle intervention. Compared to the women who reverted to normal, women with consistent AGR showed significantly lower fasting insulin concentration, lower △ins30'/△BG30'as well aslower HOMA-B. No significant differences in age, body mass index(BMI), waist circumference, blood pressure, lipid level, HsCRP and HOMA-IR were observed between the two groups. Pre-pregnancy BMI>25 kg/m2. fasting glucose level≥5. 6 mmol/L and/or 75 g oral glucose tolerance test (OGTT)2 hours glucose level≥11. 1 mmol/L during pregnancy were predictors for the AGR at 6-8 weeks after delivery. △ins30'/△BG30≤1.05 was a significant risk contributor to the consistent early postpartum AGR. Conclusion There is a high incidence of early postpartum AGR among Chinese woman with prior GDM. Beta-cell dysfunction, rather than insulin resistance or inflammation, is the predominant contributor to the early onset and consistent AGR after delivery.

  14. Physical Activity, Fitness, and Cardiometabolic Risk Factors in Adult Survivors of Childhood Cancer with a History of Hematopoietic Cell Transplantation.

    Science.gov (United States)

    Slater, Megan E; Steinberger, Julia; Ross, Julie A; Kelly, Aaron S; Chow, Eric J; Koves, Ildiko H; Hoffmeister, Paul; Sinaiko, Alan R; Petryk, Anna; Moran, Antoinette; Lee, Jill; Chow, Lisa S; Baker, K Scott

    2015-07-01

    Along with other childhood cancer survivors (CCS), hematopoietic cell transplantation (HCT) survivors are at high risk of treatment-related late effects, including cardiovascular disease and diabetes. Cardiometabolic risk factor abnormalities may be exacerbated by inadequate physical activity (PA). Relationships between PA and cardiometabolic risk factors have not been well described in CCS with HCT. PA (self reported), mobility (timed up and go test), endurance (6-minute walk test), handgrip strength, and cardiometabolic risk factors were measured in 119 HCT survivors and 66 sibling controls ages ≥18 years. Adjusted comparisons between HCT survivors and controls and between categories of low and high PA, mobility, endurance, and strength were performed with linear regression. Among HCT survivors, the high PA group had lower waist circumference (WC) (81.9 ± 2.5 versus 88.6 ± 3.1 cm ± standard error (SE), P = .009) than the low PA group, whereas the high endurance group had lower WC (77.8 ± 2.6 versus 87.8 ± 2.5 cm ± SE, P = .0001) and percent fat mass (33.6 ± 1.8 versus 39.4 ± 1.7% ± SE, P = .0008) and greater insulin sensitivity (IS) (10.9 ± 1.0 versus 7.42 ± 1.14 mg/kg/min ± SE via euglycemic insulin clamp, P = .001) than the low endurance group. Differences were greater in HCT survivors than in controls for WC between low and high PA groups, triglycerides between low and high mobility groups, and WC, systolic blood pressure, and IS between low and high endurance groups (all Pinteraction HCT survivors, suggesting that interventions directed to increase endurance in survivors may reduce the risk of future cardiovascular disease. PMID:25865649

  15. 钙钛矿太阳能电池技术发展历史与现状∗%Perovskite Solar Cells:History and Latest Researches

    Institute of Scientific and Technical Information of China (English)

    赵雨; 李惠; 关雷雷; 吴嘉达; 许宁

    2015-01-01

    Development history of perovskite solar cells is briefly reviewed.Perovskite solar cells are solid-state dye-sensitized solar cells.The microcosmic mechanism of perovskite solar cells is put forward.Energy levels of the TiO2/CH 3 NH 3 PbI3/spiro-OMeTAD junction are given,showing that the conduction band minimum and valence band maximum of CH 3 NH 3 PbI3 are well positioned for electrons injection into TiO2 and holes transfer to spiro-OMeTAD, respectively.Photovoltaic performance parameters of perovskite solar cells such as short-circuit current density,open-circuit voltages,power conversion efficiency and fill factor are summarized.The power conversion efficiency,short-circuit current density and open-circuit voltage of perovskite solar cells exceed that of a-Si thin film solar cells,while the fill factor approaches that of the latter.A conclusion is drawn that perovskite-based solar cells are expected to rea-lize industrialization and become the next generation thin-film solar cells.The bottleneck of marketization for perovs-kite-based solar cells is the fabrication of expensive hole transportation layer.The researches aim to resolve it are sum-marized.%简要回顾了钙钛矿太阳能电池的发展历史,解释了钙钛矿太阳能电池本质上是固态染料敏化太阳能电池。介绍了钙钛矿太阳能电池的微观发电机理,结合钙钛矿太阳能电池的能级图分析讨论了钙钛矿与电子传输层和空穴传输层的能级匹配。分析总结了钙钛矿太阳能电池的光伏技术参数,包括光生电流密度、开路电压、填充因子、能量转换效率以及光伏性能的稳定性。钙钛矿太阳能电池的能量转换效率、短路电流密度和开路电压均已超过非晶硅薄膜太阳能电池,填充因子与非晶硅薄膜太阳能电池很接近。钙钛矿太阳能电池有希望实现产业化而成为下一代薄膜太阳能电池。指出了钙钛矿太阳能电池大规模市场应用在制造技

  16. Characterizing simulated galaxy stellar mass histories

    CERN Document Server

    Cohn, J D

    2014-01-01

    Galaxy formation simulations can now predict many galaxy properties and their evolution through time. To go beyond studying average stellar mass history properties, we classified ensembles of simulated stellar mass histories, holding fixed their z=0 stellar mass. We applied principal component analysis (PCA) to stellar mass histories from the dark matter plus semi-analytic Millennium simulation and the hydrodynamical OverWhelmingly Large Simulations (OWLS) project, finding that a large fraction of the total scatter around the average stellar mass history for each sample is due to only one PCA fluctuation. This fluctuation differs between some different models sharing the same z=0 stellar mass and between lower (<=3e10 M_o) and higher final stellar mass Millennium samples. We correlated the PCA characterization with several $z=0$ galaxy observables (in principle observable in a survey) and galaxy halo history properties. We also explored separating galaxy stellar mass histories into classes, using the large...

  17. Hamilton's principle for beginners

    International Nuclear Information System (INIS)

    I find that students have difficulty with Hamilton's principle, at least the first time they come into contact with it, and therefore it is worth designing some examples to help students grasp its complex meaning. This paper supplies the simplest example to consolidate the learning of the quoted principle: that of a free particle moving along a line. Next, students are challenged to add gravity to reinforce the argument and, finally, a two-dimensional motion in a vertical plane is considered. Furthermore these examples force us to be very clear about such an abstract principle

  18. Principles of dynamics

    CERN Document Server

    Hill, Rodney

    2013-01-01

    Principles of Dynamics presents classical dynamics primarily as an exemplar of scientific theory and method. This book is divided into three major parts concerned with gravitational theory of planetary systems; general principles of the foundations of mechanics; and general motion of a rigid body. Some of the specific topics covered are Keplerian Laws of Planetary Motion; gravitational potential and potential energy; and fields of axisymmetric bodies. The principles of work and energy, fictitious body-forces, and inertial mass are also looked into. Other specific topics examined are kinematics

  19. Modern electronic maintenance principles

    CERN Document Server

    Garland, DJ

    2013-01-01

    Modern Electronic Maintenance Principles reviews the principles of maintaining modern, complex electronic equipment, with emphasis on preventive and corrective maintenance. Unfamiliar subjects such as the half-split method of fault location, functional diagrams, and fault finding guides are explained. This book consists of 12 chapters and begins by stressing the need for maintenance principles and discussing the problem of complexity as well as the requirements for a maintenance technician. The next chapter deals with the connection between reliability and maintenance and defines the terms fai

  20. The Principle of Proportionality

    DEFF Research Database (Denmark)

    Bennedsen, Morten; Meisner Nielsen, Kasper

    2005-01-01

    Recent policy initiatives within the harmonization of European company laws have promoted a so-called "principle of proportionality" through proposals that regulate mechanisms opposing a proportional distribution of ownership and control. We scrutinize the foundation for these initiatives by...

  1. Global ethics and principlism.

    Science.gov (United States)

    Gordon, John-Stewart

    2011-09-01

    This article examines the special relation between common morality and particular moralities in the four-principles approach and its use for global ethics. It is argued that the special dialectical relation between common morality and particular moralities is the key to bridging the gap between ethical universalism and relativism. The four-principles approach is a good model for a global bioethics by virtue of its ability to mediate successfully between universal demands and cultural diversity. The principle of autonomy (i.e., the idea of individual informed consent), however, does need to be revised so as to make it compatible with alternatives such as family- or community-informed consent. The upshot is that the contribution of the four-principles approach to global ethics lies in the so-called dialectical process and its power to deal with cross-cultural issues against the background of universal demands by joining them together. PMID:22073817

  2. Archimedes' Principle in Action

    Science.gov (United States)

    Kires, Marian

    2007-01-01

    The conceptual understanding of Archimedes' principle can be verified in experimental procedures which determine mass and density using a floating object. This is demonstrated by simple experiments using graduated beakers. (Contains 5 figures.)

  3. Ternary optical computer principle

    Institute of Scientific and Technical Information of China (English)

    金翊; 何华灿; 吕养天

    2003-01-01

    The fundamental principle and the characteristics of ternary optical computer, using horizontal polarized light, vertical polarized light and no-intensity to express information, are propounded in thispaper. The practicability to make key parts of the ternary optical computer from modern micro or integrated optical devices, opto-electronic and electro-photonic elements is discussed. The principle can be applied in three-state optical fiber communication via horizontal and vertical polarized light.

  4. Electrical and electronic principles

    CERN Document Server

    Knight, SA

    1988-01-01

    Electrical and Electronic Principles, 3 focuses on the principles involved in electrical and electronic circuits, including impedance, inductance, capacitance, and resistance.The book first deals with circuit elements and theorems, D.C. transients, and the series circuits of alternating current. Discussions focus on inductance and resistance in series, resistance and capacitance in series, power factor, impedance, circuit magnification, equation of charge, discharge of a capacitor, transfer of power, and decibels and attenuation. The manuscript then examines the parallel circuits of alternatin

  5. Remark on Heisenberg's principle

    International Nuclear Information System (INIS)

    Application of Heisenberg's principle to inertial frame transformations allows a distinction between three commutative groups of reciprocal transformations along one direction: Galilean transformations, dual transformations, and Lorentz transformations. These are three conjugate groups and for a given direction, the related commutators are all proportional to one single conjugation transformation which compensates for uniform and rectilinear motions. The three transformation groups correspond to three complementary ways of measuring space-time as a whole. Heisenberg's Principle then gets another explanation

  6. Microprocessors principles and applications

    CERN Document Server

    Debenham, Michael J

    1979-01-01

    Microprocessors: Principles and Applications deals with the principles and applications of microprocessors and covers topics ranging from computer architecture and programmed machines to microprocessor programming, support systems and software, and system design. A number of microprocessor applications are considered, including data processing, process control, and telephone switching. This book is comprised of 10 chapters and begins with a historical overview of computers and computing, followed by a discussion on computer architecture and programmed machines, paying particular attention to t

  7. PRINCIPLES OF ANIMAL BREEDING

    OpenAIRE

    Sonja Jovanovac

    2014-01-01

    University textbook Principles of Animal Breeding is intended for students of agriculture and veterinary medicine. The material is the adapted curricula of undergraduate and graduate level studies in the framework of which the modules Principles of animal breeding as well as Basics of genetics and selection of animals attended are listened. The textbook contains 14 chapters and a glossary of terms. Its concept enables combining fundamental and modern knowledge in the ...

  8. Two Coherence Principles

    OpenAIRE

    Spohn, Wolfgang

    1999-01-01

    The paper proposes two principles of coherence (thus taking up work started in Spohn (1991) "A Reason for Explanation: Explanations Provide Stable Reasons"). The latter indeed serves as a weak, but precise explication of the notion of coherence as it is used in the current epistemological discussion. After discussing their epistemological setting, the paper considers four ways of establishing these principles. They may be inferred neither from enumerative induction, nor from the nature of pro...

  9. Heisenberg's observability principle

    OpenAIRE

    Wolff, JE

    2014-01-01

    Werner Heisenberg's 1925 paper ‘Quantum-theoretical re-interpretation of kinematic and mechanical relations’ marks the beginning of quantum mechanics. Heisenberg famously claims that the paper is based on the idea that the new quantum mechanics should be ‘founded exclusively upon relationships between quantities which in principle are observable’. My paper is an attempt to understand this observability principle, and to see whether its employment is philosophically defensible. Against interpr...

  10. Are political principles stable?

    OpenAIRE

    Tibor R. Machan

    2005-01-01

    Purpose – Aims to question whether political principles, for example, those of socialism or libertarianism, have lasting significance. Design/methodology/approach – Lays out a case for the stability of at least one variety of political principle, namely that of libertarianism or classical liberalism and argues that the normative version of these positions does manage to have lasting stability and significance. Findings – There is much that is true that people do not necessarily attend to – in...

  11. Electrical and electronic principles

    CERN Document Server

    Knight, S A

    1991-01-01

    Electrical and Electronic Principles, 2, Second Edition covers the syllabus requirements of BTEC Unit U86/329, including the principles of control systems and elements of data transmission. The book first tackles series and parallel circuits, electrical networks, and capacitors and capacitance. Discussions focus on flux density, electric force, permittivity, Kirchhoff's laws, superposition theorem, arrangement of resistors, internal resistance, and powers in a circuit. The text then takes a look at capacitors in circuit, magnetism and magnetization, electromagnetic induction, and alternating v

  12. Ultrastructure observation on the cells at different life history stages of Cryptocaryon irritans (Ciliophora: Prostomatea), a parasitic ciliate of marine fishes.

    Science.gov (United States)

    Ma, Rui; Ni, Bing; Fan, Xinpeng; Warren, Alan; Yin, Fei; Gu, Fukang

    2016-09-01

    Cells of Cryptocaryon irritans at different life history stages were studied using both light and electron microscopy. The characteristics of several organelles were revealed for the first time at the ultrastructural level. It was confirmed that the cytostome of trophonts, protomonts and theronts was surrounded by cilium-palp triplets rather than ciliary triplets. The nematodesmata underlying the circumoral dikinetids were single bundles, whereas these were always paired in Prorodontids. Toxicysts were present in late-stage tomonts and theronts, but were absent in trophonts and protomonts. We posited that toxicysts might play a role in infection and invasion of host-fish tissue by theronts. The adoral brosse was unlike that of any other family of the class Prostomatea based on its location and morphology. Membranous folds were present in trophonts, protomonts and theronts. These folds were longer and more highly developed in C. irritans than in exclusively free-living prostome ciliates suggesting that they might be linked to parasitism in C. irritans. Trophonts, protomonts and theronts had multiple contractile vacuoles. The basic ultrastructure of the contractile vacuole of C. irritans was similar to that of other kinetofragminophoran ciliates. They might play different roles in different stages of the life cycle since their ultrastructure varied among trophonts, protomonts and theronts. PMID:27460894

  13. Cell Volume Effect on the Ferroelectric Stability of Perovskite Oxides PbTiO3 and BaTiO3 from First Principle Calculation

    Institute of Scientific and Technical Information of China (English)

    王渊旭; 王春雷

    2003-01-01

    Electronic structure of ferroelectric PbTiO3 and BaTiO3 is calculated by the full potential linearized augmented plane wave method. The total energy as a function of the displacement of Ti-cation is obtained for PbTiO3 and BaTiO3 at different cell volumes. At experimental cell volume, Ti-displacement lowers the total energy and the ferroelectricity is stable. When the cell volume is reduced to 90%, total energy is increased with Ti-displacement and ferroelectricity will disappear. The cell volume effect is also confirmed by comparison of the density of states of Ti and O at different cell volumes.

  14. Principles and the Development of Physical Theory: Case Studies

    Science.gov (United States)

    Hovis, Robert Corby

    Three separate articles make up the chapters of this dissertation. They were written with different aims and audiences in mind, but each deals in some way with one or more "principles" that have been invoked in argumentation and explanation in the physical sciences. The principles of concern are propositions which have an "aesthetic" or "foundational" or "philosophical" character and which are (or have been) generally believed to be widely applicable or particularly powerful--for example, the Principle of Plenitude, the Principle of Mathematical Beauty, Occam's Razor, the Cosmological Principle, and the Copernican Principle. Chapter 1 provides an overview of the nature and uses of principles in scientific reasoning and examines in some detail the use of the Principle of Plenitude in the introduction of "tachyons" (faster-than-light particles) into theoretical physics during the 1960s. Chapter 2 is a short biography of P. A. M. Dirac (1902-1984), one of the founders of quantum mechanics, who believed that the Principle of Mathematical Beauty should serve as physicists' guide to truth. Chapter 3 traces the history of the idea of faster-than-light particles in physics since the late 1800s; this idea matured with the rise of the subfield of tachyon physics in the 1960s, and (as mentioned above) physicists appealed to the Principle of Plenitude to argue for the existence of the particles, which are still only hypothetical. According to the thesis developed in these chapters, the epistemological status of principles has evolved over the history of science. While they were once hallowed as a priori truths, in modern science they have increasingly been employed critically, in light of the results of scientific inquiry. That is, science has moved toward making principles testable, subject to rejection or revision, on a par with other scientific propositions.

  15. The traveltime holographic principle

    Science.gov (United States)

    Huang, Yunsong; Schuster, Gerard T.

    2015-01-01

    Fermat's interferometric principle is used to compute interior transmission traveltimes τpq from exterior transmission traveltimes τsp and τsq. Here, the exterior traveltimes are computed for sources s on a boundary B that encloses a volume V of interior points p and q. Once the exterior traveltimes are computed, no further ray tracing is needed to calculate the interior times τpq. Therefore this interferometric approach can be more efficient than explicitly computing interior traveltimes τpq by ray tracing. Moreover, the memory requirement of the traveltimes is reduced by one dimension, because the boundary B is of one fewer dimension than the volume V. An application of this approach is demonstrated with interbed multiple (IM) elimination. Here, the IMs in the observed data are predicted from the migration image and are subsequently removed by adaptive subtraction. This prediction is enabled by the knowledge of interior transmission traveltimes τpq computed according to Fermat's interferometric principle. We denote this principle as the `traveltime holographic principle', by analogy with the holographic principle in cosmology where information in a volume is encoded on the region's boundary.

  16. GENERAL PRINCIPLES OF LAW

    Directory of Open Access Journals (Sweden)

    Elena ANGHEL

    2016-05-01

    Full Text Available According to Professor Djuvara “law can be a science, and legal knowledge can also become science when, referring to a number as large as possible of acts of those covered by law, sorts and connects them by their essential characters upon legal concepts or principles which are universally valid, just like the laws of nature”. The general principles of law take a privileged place in the positive legal order and represent the foundation of any legal construction. The essence of the legal principles resides in their generality. In respect of the term “general”, Franck Moderne raised the question on the degree of generality used in order to define a principle as being general – at the level of an institution, of a branch of the law or at the level of the entire legal order. The purpose of this study is to find out the characteristics of law principles. In our opinion, four characteristics can be mentioned.

  17. Two-photon laser-generated microtracks in 3D collagen lattices: principles of MMP-dependent and -independent collective cancer cell invasion

    International Nuclear Information System (INIS)

    Cancer invasion into an extracellular matrix (ECM) results from a biophysical reciprocal interplay between the expanding cancer lesion and tissue barriers imposed by the adjacent microenvironment. In vivo, connective tissue provides both densely packed ECM barriers adjacent to channel/track-like spaces and loosely organized zones, both of which may impact cancer invasion mode and efficiency; however little is known about how three-dimensional (3D) spaces and aligned tracks present in interstitial tissue guide cell invasion. We here describe a two-photon laser ablation procedure to generate 3D microtracks in dense 3D collagen matrices that support and guide collective cancer cell invasion. Whereas collective invasion of mammary tumor (MMT) breast cancer cells into randomly organized collagen networks required matrix metalloproteinase (MMP) activity for cell-derived collagen breakdown, re-alignment and track generation, preformed tracks supported MMP-independent collective invasion down to a track caliber of 3 µm. Besides contact guidance along the track of least resistance and initial cell deformation (squeezing), MMP-independent collective cell strands led to secondary track expansion by a pushing mechanism. Thus, two-photon laser ablation is useful to generate barrier-free microtracks in a 3D ECM which guide collective invasion independently of pericellular proteolysis

  18. Principles of musical acoustics

    CERN Document Server

    Hartmann, William M

    2013-01-01

    Principles of Musical Acoustics focuses on the basic principles in the science and technology of music. Musical examples and specific musical instruments demonstrate the principles. The book begins with a study of vibrations and waves, in that order. These topics constitute the basic physical properties of sound, one of two pillars supporting the science of musical acoustics. The second pillar is the human element, the physiological and psychological aspects of acoustical science. The perceptual topics include loudness, pitch, tone color, and localization of sound. With these two pillars in place, it is possible to go in a variety of directions. The book treats in turn, the topics of room acoustics, audio both analog and digital, broadcasting, and speech. It ends with chapters on the traditional musical instruments, organized by family. The mathematical level of this book assumes that the reader is familiar with elementary algebra. Trigonometric functions, logarithms and powers also appear in the book, but co...

  19. Developing principles of growth

    DEFF Research Database (Denmark)

    Neergaard, Helle; Fleck, Emma

    Although it has been widely recognized that the growth of women-owned businesses is central to wealth creation, innovation and economic development; limited attention has been devoted to understanding small business growth from a female perspective.This research seeks to develop an understanding of...... the principles of growth among women-owned firms. Using an in-depth case study methodology, data was collected from women-owned firms in Denmark and Ireland, as these countries are similar in contextual terms, e.g. population and business composition, dominated by micro, small and medium......-sized enterprises. Extending on principles put forward in effectuation theory, we propose that women grow their firms according to five principles which enable women’s enterprises to survive in the face of crises such as the current financial world crisis....

  20. How History Helped Einstein in Special Relativity

    Science.gov (United States)

    Martinez, Alberto

    2013-04-01

    I will discuss how the German intellectual movement known as ``critical history'' motivated several physicists in the late 1900s to radically analyze the fundamental principles of mechanics, leading eventually to Einstein's special theory of relativity. Eugen Karl Dühring, Johann Bernhard Stallo, Ludwig Lange, and Ernst Mach wrote critical histories of mechanics, some of which emphasized notions of relativity and observation, in opposition to old metaphysical concepts that seemed to infect the foundations of physics. This strand of critical history included the ``genetic method'' of analyzing how concepts develop over time, in our minds, by way of ordinary experiences, which by 1904 was young Albert Einstein's favorite approach for examining fundamental notions. Thus I will discuss how history contributed in Einstein's path to relativity, as well as comment more generally on Einstein's views on history.

  1. Teaching/learning principles

    Science.gov (United States)

    Hankins, D. B.; Wake, W. H.

    1981-01-01

    The potential remote sensing user community is enormous, and the teaching and training tasks are even larger; however, some underlying principles may be synthesized and applied at all levels from elementary school children to sophisticated and knowledgeable adults. The basic rules applying to each of the six major elements of any training course and the underlying principle involved in each rule are summarized. The six identified major elements are: (1) field sites for problems and practice; (2) lectures and inside study; (3) learning materials and resources (the kit); (4) the field experience; (5) laboratory sessions; and (6) testing and evaluation.

  2. Electrical principles 3 checkbook

    CERN Document Server

    Bird, J O

    2013-01-01

    Electrical Principles 3 Checkbook aims to introduce students to the basic electrical principles needed by technicians in electrical engineering, electronics, and telecommunications.The book first tackles circuit theorems, single-phase series A.C. circuits, and single-phase parallel A.C. circuits. Discussions focus on worked problems on parallel A.C. circuits, worked problems on series A.C. circuits, main points concerned with D.C. circuit analysis, worked problems on circuit theorems, and further problems on circuit theorems. The manuscript then examines three-phase systems and D.C. transients

  3. Mechanical engineering principles

    CERN Document Server

    Bird, John

    2014-01-01

    A student-friendly introduction to core engineering topicsThis book introduces mechanical principles and technology through examples and applications, enabling students to develop a sound understanding of both engineering principles and their use in practice. These theoretical concepts are supported by 400 fully worked problems, 700 further problems with answers, and 300 multiple-choice questions, all of which add up to give the reader a firm grounding on each topic.The new edition is up to date with the latest BTEC National specifications and can also be used on undergraduate courses in mecha

  4. Principles of statistics

    CERN Document Server

    Bulmer, M G

    1979-01-01

    There are many textbooks which describe current methods of statistical analysis, while neglecting related theory. There are equally many advanced textbooks which delve into the far reaches of statistical theory, while bypassing practical applications. But between these two approaches is an unfilled gap, in which theory and practice merge at an intermediate level. Professor M. G. Bulmer's Principles of Statistics, originally published in 1965, was created to fill that need. The new, corrected Dover edition of Principles of Statistics makes this invaluable mid-level text available once again fo

  5. On Figures of speech, Cooperative Principle and Politeness Principle

    Institute of Scientific and Technical Information of China (English)

    于永丽; 朱丽萍

    2008-01-01

    To accomplish the communication efficiently and successfully, the people usually follow some certain principle in conversation. Grice named this principle as the cooperative principle. The politeness principle that Leech has developed can explain some phenomenon from a different perspective that the cooperative principle cannot. Nowadays, the use of the figures of speech is becoming more and more often. What we should pay attention to is the fact that the use of the figures of speech violates the cooperative principle, while following the politeness principle to a certain extent. And this paper aims to discuss the relationship among them, to provide some information for the readers.

  6. Authentic tasks in higher education: Studying design principles for assessment

    OpenAIRE

    Keulen, H. van; Van den Berg, I.; Ramaekers, S.

    2006-01-01

    Students may benefit significantly from learning through authentic tasks. But how do we assess their learning outcomes, taking into account the specific characteristics of authentic tasks? In the second presentation of this symposium on design principles for authentic tasks we present and discuss principles for assessment procedures in authentic tasks from three different domains: clinical reasoning in Veterinary Science; internships in Medicine; and essay writing in History, all at Utrecht U...

  7. Extended Mach Principle.

    Science.gov (United States)

    Rosen, Joe

    1981-01-01

    Discusses the meaning of symmetry of the laws of physics and symmetry of the universe and the connection between symmetries and asymmetries of the laws of physics and those of the universe. An explanation of Hamilton's principle is offered. The material is suitable for informal discussions with students. (Author/SK)

  8. Principles of economics textbooks

    DEFF Research Database (Denmark)

    Madsen, Poul Thøis

    2012-01-01

    Has the financial crisis already changed US principles of economics textbooks? Rather little has changed in individual textbooks, but taken as a whole ten of the best-selling textbooks suggest rather encompassing changes of core curriculum. A critical analysis of these changes shows how individual...

  9. Principles of Bridge Reliability

    DEFF Research Database (Denmark)

    Thoft-Christensen, Palle; Nowak, Andrzej S.

    The paper gives a brief introduction to the basic principles of structural reliability theory and its application to bridge engineering. Fundamental concepts like failure probability and reliability index are introduced. Ultimate as well as serviceability limit states for bridges are formulated...

  10. Jaynes principle versus entanglement

    CERN Document Server

    Horodecki, M; Horodecki, R; Horodecki, Michal; Horodecki, Pawel; Horodecki, Ryszard

    1997-01-01

    We show that the Jaynes principle of maximum entropy when applied to compound quantum system can produce states with non-minimal entanglement. The resulting surplus of entanglement occurs for the sets of both local and nonlocal observables. We also point out that the estimation of the parameters of quantum noise should be based on minimization of entanglement rather than maximization of entropy.

  11. On Weak Markov's Principle

    DEFF Research Database (Denmark)

    Kohlenbach, Ulrich Wilhelm

    We show that the so-called weak Markov's principle (WMP) which states that every pseudo-positive real number is positive is underivable in E-HA + AC. Since allows one to formalize (atl eastl arge parts of) Bishop's constructive mathematics, this makes it unlikely that WMP can be proved within the...

  12. The traveltime holographic principle

    KAUST Repository

    Huang, Y.

    2014-11-06

    Fermat\\'s interferometric principle is used to compute interior transmission traveltimes τpq from exterior transmission traveltimes τsp and τsq. Here, the exterior traveltimes are computed for sources s on a boundary B that encloses a volume V of interior points p and q. Once the exterior traveltimes are computed, no further ray tracing is needed to calculate the interior times τpq. Therefore this interferometric approach can be more efficient than explicitly computing interior traveltimes τpq by ray tracing. Moreover, the memory requirement of the traveltimes is reduced by one dimension, because the boundary B is of one fewer dimension than the volume V. An application of this approach is demonstrated with interbed multiple (IM) elimination. Here, the IMs in the observed data are predicted from the migration image and are subsequently removed by adaptive subtraction. This prediction is enabled by the knowledge of interior transmission traveltimes τpq computed according to Fermat\\'s interferometric principle. We denote this principle as the ‘traveltime holographic principle’, by analogy with the holographic principle in cosmology where information in a volume is encoded on the region\\'s boundary.

  13. Matters of Principle.

    Science.gov (United States)

    Martz, Carlton

    1999-01-01

    This issue of "Bill of Rights in Action" looks at individuals who have stood on principle against authority or popular opinion. The first article investigates John Adams and his defense of British soldiers at the Boston Massacre trials. The second article explores Archbishop Thomas Becket's fatal conflict with England's King Henry II. The final…

  14. Classification and structural analysis of live and dead salmonella cells using fourier transform infrared (FT-IR) spectroscopy and principle component analysis (PCA)

    Science.gov (United States)

    Fourier Transform Infrared Spectroscopy (FT-IR) was used to detect Salmonella typhimurium and Salmonella enteritidis foodborne bacteria and distinguish between live and dead cells of both serotypes. Bacteria were loaded individually on the ZnSe Attenuated Total Reflection (ATR) crystal surface and s...

  15. Maturing Gracefully? Curriculum Standards for History and Archaeology.

    Science.gov (United States)

    Black, Mary S.

    2001-01-01

    Explores the similarities and differences between the disciplines of history and archaeology. Examines the standards and principles recently proposed for teaching history and archaeology to determine the areas of difference and commonality. Addresses the issues of historical and archaeological thinking describing each in detail. (CMK)

  16. Politeness Principle and Intercultural Communication

    Institute of Scientific and Technical Information of China (English)

    周宇岚

    2007-01-01

    There are many potential problems in intercultural communications. Politeness principle is very important in helping improving intercultural communications. But different cultures have various standard of politeness principle. This essay discusses the very different points of view on politeness principle between Chinese people and westerners, and studies how the context and settings affect the practice of politeness principle. At the ending of the essay, the guiding significance of politeness principle is p...

  17. Basic Principles of Anodic Stripping Voltammetry (ASV)

    OpenAIRE

    2012-01-01

    In this interactive exercise, the basic principles of Anodic Stripping Voltammetry are shown. Each step of the voltammetric process is described using simulated animations. This activity illustrates what takes place in the voltammetric cell when this technique is applied to the determination of cadmium as well as to the simultaneous determination of copper and cadmium.

  18. Amorphous silicon crystalline silicon heterojunction solar cells

    CERN Document Server

    Fahrner, Wolfgang Rainer

    2013-01-01

    Amorphous Silicon/Crystalline Silicon Solar Cells deals with some typical properties of heterojunction solar cells, such as their history, the properties and the challenges of the cells, some important measurement tools, some simulation programs and a brief survey of the state of the art, aiming to provide an initial framework in this field and serve as a ready reference for all those interested in the subject. This book helps to ""fill in the blanks"" on heterojunction solar cells. Readers will receive a comprehensive overview of the principles, structures, processing techniques and the curre

  19. Consistency Principle in Biological Dynamical Systems

    OpenAIRE

    Kaneko, Kunihiko; Furusawa, Chikara

    2008-01-01

    We propose a principle of consistency between different hierarchical levels of biological systems. Given a consistency between molecule replication and cell reproduction, universal statistical laws on cellular chemical abundances are derived and confirmed experimentally. They include a power law distribution of gene expressions, a lognormal distribution of cellular chemical abundances over cells, and embedding of the power law into the network connectivity distribution. Second, given a consis...

  20. Quantitative in vivo cell-surface receptor imaging in oncology: kinetic modeling and paired-agent principles from nuclear medicine and optical imaging

    Science.gov (United States)

    Tichauer, Kenneth M.; Wang, Yu; Pogue, Brian W.; Liu, Jonathan T. C.

    2015-07-01

    The development of methods to accurately quantify cell-surface receptors in living tissues would have a seminal impact in oncology. For example, accurate measures of receptor density in vivo could enhance early detection or surgical resection of tumors via protein-based contrast, allowing removal of cancer with high phenotype specificity. Alternatively, accurate receptor expression estimation could be used as a biomarker to guide patient-specific clinical oncology targeting of the same molecular pathway. Unfortunately, conventional molecular contrast-based imaging approaches are not well adapted to accurately estimating the nanomolar-level cell-surface receptor concentrations in tumors, as most images are dominated by nonspecific sources of contrast such as high vascular permeability and lymphatic inhibition. This article reviews approaches for overcoming these limitations based upon tracer kinetic modeling and the use of emerging protocols to estimate binding potential and the related receptor concentration. Methods such as using single time point imaging or a reference-tissue approach tend to have low accuracy in tumors, whereas paired-agent methods or advanced kinetic analyses are more promising to eliminate the dominance of interstitial space in the signals. Nuclear medicine and optical molecular imaging are the primary modalities used, as they have the nanomolar level sensitivity needed to quantify cell-surface receptor concentrations present in tissue, although each likely has a different clinical niche.

  1. Quantitative in vivo cell-surface receptor imaging in oncology: kinetic modeling and paired-agent principles from nuclear medicine and optical imaging

    International Nuclear Information System (INIS)

    The development of methods to accurately quantify cell-surface receptors in living tissues would have a seminal impact in oncology. For example, accurate measures of receptor density in vivo could enhance early detection or surgical resection of tumors via protein-based contrast, allowing removal of cancer with high phenotype specificity. Alternatively, accurate receptor expression estimation could be used as a biomarker to guide patient-specific clinical oncology targeting of the same molecular pathway. Unfortunately, conventional molecular contrast-based imaging approaches are not well adapted to accurately estimating the nanomolar-level cell-surface receptor concentrations in tumors, as most images are dominated by nonspecific sources of contrast such as high vascular permeability and lymphatic inhibition. This article reviews approaches for overcoming these limitations based upon tracer kinetic modeling and the use of emerging protocols to estimate binding potential and the related receptor concentration. Methods such as using single time point imaging or a reference-tissue approach tend to have low accuracy in tumors, whereas paired-agent methods or advanced kinetic analyses are more promising to eliminate the dominance of interstitial space in the signals. Nuclear medicine and optical molecular imaging are the primary modalities used, as they have the nanomolar level sensitivity needed to quantify cell-surface receptor concentrations present in tissue, although each likely has a different clinical niche. (topical review)

  2. 基于电阻抗法原理的全自动五分类血球仪的研究%Based on the Electrical Impedance Principle Automatic Five Categories of Blood Cell Analyzer

    Institute of Scientific and Technical Information of China (English)

    金碧祥

    2013-01-01

      白细胞分析技术早以开始研究,最早的白细胞分析仪是在1974年诞生的。它被称为HEMALOG D,这个时候的分析仪已经具备了一些初步白细胞分类功能。本文是对电阻抗法血液分析仪的工作原理以及对五分类血球仪的相关的介绍,结合BC-6800全自动血液细胞分析仪展开描述,主要是针对于电阻抗法对全自动五分类血球仪所进行的研究。%White blood cell analysis technology in long ago began to research, the original white blood cell analyzer was born in 1974. He was known as the HEMALOG D, points already have some preliminary right one for this time of the leukocyte classification function. This article is working principle of resistance KangFa blood analyzer and blood corpus-cle analyzer for five classification related introduction, combined with the description of BC - 6800 automatic blood cell analyzer, mainly against the resistance of fully automatic blood corpuscle analyzer five classification by KangFa research.

  3. Principles of radiation therapy

    International Nuclear Information System (INIS)

    This chapter reviews (a) the natural history of metastatic bone disease in general terms and as it impacts on the use of radiation as therapy; (b) the clinical and radiographic evaluations used to guide the application of irradiation; and (c) the methods, results, and toxicities of various techniques of irradiation

  4. Principles of photonics

    CERN Document Server

    Liu, Jia-Ming

    2016-01-01

    With this self-contained and comprehensive text, students will gain a detailed understanding of the fundamental concepts and major principles of photonics. Assuming only a basic background in optics, readers are guided through key topics such as the nature of optical fields, the properties of optical materials, and the principles of major photonic functions regarding the generation, propagation, coupling, interference, amplification, modulation, and detection of optical waves or signals. Numerous examples and problems are provided throughout to enhance understanding, and a solutions manual containing detailed solutions and explanations is available online for instructors. This is the ideal resource for electrical engineering and physics undergraduates taking introductory, single-semester or single-quarter courses in photonics, providing them with the knowledge and skills needed to progress to more advanced courses on photonic devices, systems and applications.

  5. Principles of Fourier analysis

    CERN Document Server

    Howell, Kenneth B

    2001-01-01

    Fourier analysis is one of the most useful and widely employed sets of tools for the engineer, the scientist, and the applied mathematician. As such, students and practitioners in these disciplines need a practical and mathematically solid introduction to its principles. They need straightforward verifications of its results and formulas, and they need clear indications of the limitations of those results and formulas.Principles of Fourier Analysis furnishes all this and more. It provides a comprehensive overview of the mathematical theory of Fourier analysis, including the development of Fourier series, "classical" Fourier transforms, generalized Fourier transforms and analysis, and the discrete theory. Much of the author''s development is strikingly different from typical presentations. His approach to defining the classical Fourier transform results in a much cleaner, more coherent theory that leads naturally to a starting point for the generalized theory. He also introduces a new generalized theory based ...

  6. Principles of geodynamics

    CERN Document Server

    Scheidegger, Adrian E

    1982-01-01

    Geodynamics is commonly thought to be one of the subjects which provide the basis for understanding the origin of the visible surface features of the Earth: the latter are usually assumed as having been built up by geodynamic forces originating inside the Earth ("endogenetic" processes) and then as having been degrad­ ed by geomorphological agents originating in the atmosphere and ocean ("exogenetic" agents). The modem view holds that the sequence of events is not as neat as it was once thought to be, and that, in effect, both geodynamic and geomorphological processes act simultaneously ("Principle of Antagonism"); however, the division of theoretical geology into the principles of geodynamics and those of theoretical geomorphology seems to be useful for didactic purposes. It has therefore been maintained in the present writer's works. This present treatise on geodynamics is the first part of the author's treatment of theoretical geology, the treatise on Theoretical Geomorphology (also published by the Sprin...

  7. Principles of mathematical modeling

    CERN Document Server

    Dym, Clive

    2004-01-01

    Science and engineering students depend heavily on concepts of mathematical modeling. In an age where almost everything is done on a computer, author Clive Dym believes that students need to understand and "own" the underlying mathematics that computers are doing on their behalf. His goal for Principles of Mathematical Modeling, Second Edition, is to engage the student reader in developing a foundational understanding of the subject that will serve them well into their careers. The first half of the book begins with a clearly defined set of modeling principles, and then introduces a set of foundational tools including dimensional analysis, scaling techniques, and approximation and validation techniques. The second half demonstrates the latest applications for these tools to a broad variety of subjects, including exponential growth and decay in fields ranging from biology to economics, traffic flow, free and forced vibration of mechanical and other systems, and optimization problems in biology, structures, an...

  8. Principles of Mobile Communication

    CERN Document Server

    Stüber, Gordon L

    2012-01-01

    This mathematically rigorous overview of physical layer wireless communications is now in a third, fully revised and updated edition. Along with coverage of basic principles sufficient for novice students, the volume includes plenty of finer details that will satisfy the requirements of graduate students aiming to research the topic in depth. It also has a role as a handy reference for wireless engineers. The content stresses core principles that are applicable to a broad range of wireless standards. Beginning with a survey of the field that introduces an array of issues relevant to wireless communications and which traces the historical development of today’s accepted wireless standards, the book moves on to cover all the relevant discrete subjects, from radio propagation to error probability performance and cellular radio resource management. A valuable appendix provides a succinct and focused tutorial on probability and random processes, concepts widely used throughout the book. This new edition, revised...

  9. Procedure system principles

    International Nuclear Information System (INIS)

    Procedures establish how an organization performs specific tasks to accomplish its basic goals and objectives. In 1990, the US Department of Energy (DOE) started the process of defining requirements to be used for procedures throughout the DOE nuclear complex. In response to the customer needs of the complex, the department's initial steps in this process were to develop two documents: a writer's guide for technical procedures and the principles of procedure writing upon which it was based. The US Nuclear Regulatory Commission and Institute for Nuclear Power Operations literature addresses the control and use of procedures. There was, however, no regulatory guidance on developing and managing a procedure system. In 1991, an effort was undertaken to provide such guidance for DOE nuclear facilities. A companion paper by Grider and Plung describes how a performance-tested advisory group developed this guidance. This paper describes the procedure system principles that were developed through this process

  10. Principles of harmonic analysis

    CERN Document Server

    Deitmar, Anton

    2014-01-01

    This book offers a complete and streamlined treatment of the central principles of abelian harmonic analysis: Pontryagin duality, the Plancherel theorem and the Poisson summation formula, as well as their respective generalizations to non-abelian groups, including the Selberg trace formula. The principles are then applied to spectral analysis of Heisenberg manifolds and Riemann surfaces. This new edition contains a new chapter on p-adic and adelic groups, as well as a complementary section on direct and projective limits. Many of the supporting proofs have been revised and refined. The book is an excellent resource for graduate students who wish to learn and understand harmonic analysis and for researchers seeking to apply it.

  11. Uncertainty Principle Respects Locality

    CERN Document Server

    Wang, Dongsheng

    2013-01-01

    The notion of nonlocality implicitly implies there might be some kind of spooky action at a distance in nature, however, the validity of quantum mechanics has been well tested up to now. In this work it is argued that the notion of nonlocality is physically improper, the basic principle of locality in nature is well respected by quantum mechanics, namely, the uncertainty principle. We show that the quantum bound on the Clauser, Horne, Shimony, and Holt (CHSH) inequality can be recovered from the uncertainty relation in a multipartite setting, and the same bound exists classically which indicates that nonlocality does not capture the essence of quantum and then distinguish quantum mechanics and classical mechanics properly. We further argue that the super-quantum correlation demonstrated by the nonlocal box is not physically comparable with the quantum one, as the result, the physical foundation for the existence of nonlocality is falsified. The origin of the quantum structure of nature still remains to be exp...

  12. Principles of systems science

    CERN Document Server

    Mobus, George E

    2015-01-01

    This pioneering text provides a comprehensive introduction to systems structure, function, and modeling as applied in all fields of science and engineering. Systems understanding is increasingly recognized as a key to a more holistic education and greater problem solving skills, and is also reflected in the trend toward interdisciplinary approaches to research on complex phenomena. The subject of systems science, as a basis for understanding the components and drivers of phenomena at all scales, should be viewed with the same importance as a traditional liberal arts education. Principles of Systems Science contains many graphs, illustrations, side bars, examples, and problems to enhance understanding. From basic principles of organization, complexity, abstract representations, and behavior (dynamics) to deeper aspects such as the relations between information, knowledge, computation, and system control, to higher order aspects such as auto-organization, emergence and evolution, the book provides an integrated...

  13. Principles of Natural Photosynthesis.

    Science.gov (United States)

    Krewald, Vera; Retegan, Marius; Pantazis, Dimitrios A

    2016-01-01

    Nature relies on a unique and intricate biochemical setup to achieve sunlight-driven water splitting. Combined experimental and computational efforts have produced significant insights into the structural and functional principles governing the operation of the water-oxidizing enzyme Photosystem II in general, and of the oxygen-evolving manganese-calcium cluster at its active site in particular. Here we review the most important aspects of biological water oxidation, emphasizing current knowledge on the organization of the enzyme, the geometric and electronic structure of the catalyst, and the role of calcium and chloride cofactors. The combination of recent experimental work on the identification of possible substrate sites with computational modeling have considerably limited the possible mechanistic pathways for the critical O-O bond formation step. Taken together, the key features and principles of natural photosynthesis may serve as inspiration for the design, development, and implementation of artificial systems. PMID:26099285

  14. Principles of artificial intelligence

    CERN Document Server

    Nilsson, Nils J

    1980-01-01

    A classic introduction to artificial intelligence intended to bridge the gap between theory and practice, Principles of Artificial Intelligence describes fundamental AI ideas that underlie applications such as natural language processing, automatic programming, robotics, machine vision, automatic theorem proving, and intelligent data retrieval. Rather than focusing on the subject matter of the applications, the book is organized around general computational concepts involving the kinds of data structures used, the types of operations performed on the data structures, and the properties of th

  15. Principles of electrical safety

    CERN Document Server

    Sutherland, Peter E

    2015-01-01

    Principles of Electrical Safety discusses current issues in electrical safety, which are accompanied by series' of practical applications that can be used by practicing professionals, graduate students, and researchers. .  Provides extensive introductions to important topics in electrical safety Comprehensive overview of inductance, resistance, and capacitance as applied to the human body Serves as a preparatory guide for today's practicing engineers

  16. Principles of (Behavioral) Economics

    OpenAIRE

    David Laibson; List, John A.

    2015-01-01

    Behavioral economics has become an important and integrated component of modern economics. Behavioral economists embrace the core principles of economics—optimization and equilibrium—and seek to develop and extend those ideas to make them more empirically accurate. Behavioral models assume that economic actors try to pick the best feasible option and those actors sometimes make mistakes. Behavioral ideas should be incorporated throughout the first-year undergraduate course. Instructors should...

  17. PREFERENCE, PRINCIPLE AND PRACTICE

    DEFF Research Database (Denmark)

    Skovsgaard, Morten; Bro, Peter

    2011-01-01

    journalists justify themselves and their work. This article introduces an analytical framework for understanding legitimacy in a journalistic context. A framework based on a review of material ranging from historical accounts to research articles, and book-length studies. The framework comprises three...... distinct, but interconnected categories*preference, principle, and practice. Through this framework, historical attempts to justify journalism and journalists are described and discussed in the light of the present challenges for the profession....

  18. Advertisement without Ethical Principles?

    OpenAIRE

    Wojciech Słomski

    2007-01-01

    The article replies to the question, whether the advertisement can exist without ethical principles or ethics should be the basis of the advertisement. One can say that the ethical opinion of the advertisement does not depend on content and the form of advertising content exclusively, but also on recipientís consciousness. The advertisement appeals to the emotions more than to the intellect, thus restricting the area of conscious and based on rational premises choice, so it is morally bad. It...

  19. PRINCIPLES OF CHANGE MANAGEMENT

    OpenAIRE

    Eduard IONESCU; Rodica DRAGOMIROIU; Lacramioara Rodica HURLOIU; Petru ROSCA

    2014-01-01

    Change management process needs to define certain principles and apply them effectively in order to achieve the best possible results. Understanding how certain members of the organization react to change will greatly influence how they will cope with the implementation of change, how their work will be productive during and after the implementation of change and that will be the result the end of the process.

  20. Principles of Safety Pharmacology

    OpenAIRE

    Pugsley, M. K.; Authier, S; Curtis, M J

    2008-01-01

    Safety Pharmacology is a rapidly developing discipline that uses the basic principles of pharmacology in a regulatory-driven process to generate data to inform risk/benefit assessment. The aim of Safety Pharmacology is to characterize the pharmacodynamic/pharmacokinetic (PK/PD) relationship of a drug's adverse effects using continuously evolving methodology. Unlike toxicology, Safety Pharmacology includes within its remit a regulatory requirement to predict the risk of rare lethal events. Thi...

  1. General Principles Governing Liability

    International Nuclear Information System (INIS)

    This paper contains a brief review of the basic principles which govern the special regime of liability and compensation for nuclear damage originating on nuclear installations, in particular the strict and exclusive liability of the nuclear operator, the provision of a financial security to cover this liability and the limits applicable both in amount and in time. The paper also reviews the most important international agreements currently in force which constitute the foundation of this special regime. (author)

  2. Fundamental Safety Principles

    International Nuclear Information System (INIS)

    This work presents a summary of the IAEA Safety Standards Series publication No. SF-1 entitled FUDAMENTAL Safety PRINCIPLESpublished on 2006. This publication states the fundamental safety objective and ten associated safety principles, and briefly describes their intent and purposes. Safety measures and security measures have in common the aim of protecting human life and health and the environment. These safety principles are: 1) Responsibility for safety, 2) Role of the government, 3) Leadership and management for safety, 4) Justification of facilities and activities, 5) Optimization of protection, 6) Limitation of risks to individuals, 7) Protection of present and future generations, 8) Prevention of accidents, 9)Emergency preparedness and response and 10) Protective action to reduce existing or unregulated radiation risks. The safety principles concern the security of facilities and activities to the extent that they apply to measures that contribute to both safety and security. Safety measures and security measures must be designed and implemented in an integrated manner so that security measures do not compromise safety and safety measures do not compromise security.

  3. Principles and methods of radiation protection

    International Nuclear Information System (INIS)

    The history of radiation protection in Czechoslovakia is briefly outlined and the principles thereof are shown. The individual types of radiation effects, ie., early and delayed effects, are listed according to their symptoms. The concepts of the so-called stochastic and nonstochastic effects are explained in detail. The classification of radiation effects and the life-long risk coefficients of malignant tumours induced by radiation are tabulated. The criteria and methods of radiation protection are treated in detail with reference to ICRP recommendations and the Decree of the Ministry of Health of the Czech Socialist Republic on health protection from ionizing radiations. (L.O.)

  4. The Gyroplane : Its Principles and Its Possibilities

    Science.gov (United States)

    Breguet, Louis

    1937-01-01

    This report begins by indicating several simple principles concerning the velocity distribution over the blades of a lifting propeller of diameter D, revolving at n revolutions per second, and animated by a horizontal movement of translation at speed V. The calculation, compared with the test data, has shown that the aerodynamic action of the air on the blades depends almost only on the velocity components in a plane at right angles to the blade span. A history of gyroplane and gyrocopter development is presented as well as the advantages in using both types of craft.

  5. The role of ethics and principles

    International Nuclear Information System (INIS)

    There has been a hundred-year history of the uses of radiation in medicine and industry. Throughout that time there has also been advice on the need to protect people from the hazards associated with exposure. This paper traces the evolution of protection standards through the differing phases that are identified. These phases reflect changes both in scientific understanding of the biological effects of exposure and of the social and ethical standards to be applied. As a result, the principles used for protection have continuously evolved and are likely to continue to do so in the future. (author)

  6. Bioclimatic underground architecture: Development and principles

    Directory of Open Access Journals (Sweden)

    Stojić Jasmina

    2009-01-01

    Full Text Available The principal idea of paper lies in analyzing contemporary architectural challenges, concerning climate changes, global warming, renewable energy deficiency and population growth. The relevant examples and principles of sustainable and selfsustainable architecture development throughout history are presented. Underground structures as passive solar systems, vegetation used as insulation, ventilation and isolation are given as one of possible solutions for this global phenomenon. By studying the model of Nature, certain solutions imitating systems and laws of flora and fauna are given that will insure the necessary savings of non-renewable energy during the building construction and their later energy consumption.

  7. Thermoelectricity an introduction to the principles

    CERN Document Server

    MacDonald, D K C

    2006-01-01

    This introductory treatment provides an understanding of the fundamental concepts and principles involved in the study of thermoelectricity in solids and of conduction in general. Aimed at graduate-level students and those interested in basic theory, it will be especially valuable to experimental physicists working in fields connected with electron transport and to theoreticians seeking a survey of thermoelectricity and related questions.Chronicling the early history of thermoelectricity from its discovery to modern times, this text features a considerable amount of experimental data and discu

  8. Role of symmetry principles in high energy physics

    International Nuclear Information System (INIS)

    Quantum Mechanics and its extension Quantum Field Theory with the help of symmetry principles as keys have played an important role in studying the nature of fundamental constituents of matter and their intractions. A brief history of these areas of physics is the primary aim of this review article. (author). 19 refs

  9. A Progressive Approach to the Education of Teachers: Some Principles from Bank Street College of Education. Occasional Paper Series 18

    Science.gov (United States)

    Nager, Nancy; Shapiro, Edna K.

    2007-01-01

    This occasional paper presents Bank Street's approach as represented in a set of five interrelated principles. It begins by briefly describing the origins and rationale of teacher education at Bank Street. From this description are generated principles that emerge from Bank Street's history and practice, linking each principle to classroom images…

  10. Efficiency principles of consulting entrepreneurship

    OpenAIRE

    Moroz Yustina S.; Drozdov Igor N.

    2015-01-01

    The article reviews the primary goals and problems of consulting entrepreneurship. The principles defining efficiency of entrepreneurship in the field of consulting are generalized. The special attention is given to the importance of ethical principles of conducting consulting entrepreneurship activity.

  11. Exploring the electrochemical properties of hole transport materials with spiro-cores for efficient perovskite solar cells from first-principles.

    Science.gov (United States)

    Chi, Wei-Jie; Li, Quan-Song; Li, Ze-Sheng

    2016-03-10

    Perovskite solar cells (PSCs) with organic small molecules as hole transport materials (HTMs) have attracted considerable attention due to their power conversion efficiencies as high as 20%. In the present work, three new spiro-type hole transport materials with spiro-cores, i.e. Spiro-F1, Spiro-F2 and Spiro-F3, are investigated by using density functional theory combined with the Marcus theory and Einstein relation. Based on the calculated and experimental highest occupied molecular orbital (HOMO) levels of 30 reference molecules, an empirical equation, which can predict the HOMO levels of hole transport materials accurately, is proposed. Moreover, a simplified method, in which the hole transport pathways are simplified to be one-dimensional, is presented and adopted to qualitatively compare the molecular hole mobilities. The calculated results show that the perovskite solar cells with the new hole transport materials can have higher open-circuit voltages due to the lower HOMO levels of Spiro-F1 (-5.31 eV), Spiro-F2 (-5.42 eV) and Spiro-F3 (-5.10 eV) compared with that of Spiro-OMeTAD (-5.09 eV). Furthermore, the hole mobilities of Spiro-F1 (1.75 × 10(-2) cm(2) V(-1) s(-1)) and Spiro-F3 (7.59 × 10(-3) cm(2) V(-1) s(-1)) are 3.1 and 1.4 times that of Spiro-OMeTAD (5.65 × 10(-3) cm(2) V(-1) s(-1)) respectively, due to small reorganization energies and large transfer integrals. Interestingly, the stability properties of Spiro-F1 and Spiro-F2 are shown to be comparable to that of Spiro-OMeTAD, and the dimers of Spiro-F2 and Spiro-F3 possess better stability than that of Spiro-OMeTAD. Taking into consideration the appropriate HOMO level, improved hole mobility and enhanced stability, Spiro-F1 and Spiro-F3 may become the most promising alternatives to Spiro-OMeTAD. The present work offers a new design strategy and reliable calculation methods towards the development of excellent organic small molecules as HTMs for highly efficient and stable PSCs. PMID:26932177

  12. Principles of tendon transfers.

    Science.gov (United States)

    Coulet, B

    2016-04-01

    Tendon transfers are carried out to restore functional deficits by rerouting the remaining intact muscles. Transfers are highly attractive in the context of hand surgery because of the possibility of restoring the patient's ability to grip. In palsy cases, tendon transfers are only used when a neurological procedure is contraindicated or has failed. The strategy used to restore function follows a common set of principles, no matter the nature of the deficit. The first step is to clearly distinguish between deficient muscles and muscles that could be transferred. Next, the type of palsy will dictate the scope of the program and the complexity of the gripping movements that can be restored. Based on this reasoning, a surgical strategy that matches the means (transferable muscles) with the objectives (functions to restore) will be established and clearly explained to the patient. Every paralyzed hand can be described using three parameters. 1) Deficient segments: wrist, thumb and long fingers; 2) mechanical performance of muscles groups being revived: high energy-wrist extension and finger flexion that require strong transfers with long excursion; low energy-wrist flexion and finger extension movements that are less demanding mechanically, because they can be accomplished through gravity alone in some cases; 3) condition of the two primary motors in the hand: extrinsics (flexors and extensors) and intrinsics (facilitator). No matter the type of palsy, the transfer surgery follows the same technical principles: exposure, release, fixation, tensioning and rehabilitation. By performing an in-depth analysis of each case and by following strict technical principles, tendon transfer surgery leads to reproducible results; this allows the surgeon to establish clear objectives for the patient preoperatively. PMID:27117119

  13. Exploring the electrochemical properties of hole transport materials with spiro-cores for efficient perovskite solar cells from first-principles

    Science.gov (United States)

    Chi, Wei-Jie; Li, Quan-Song; Li, Ze-Sheng

    2016-03-01

    Perovskite solar cells (PSCs) with organic small molecules as hole transport materials (HTMs) have attracted considerable attention due to their power conversion efficiencies as high as 20%. In the present work, three new spiro-type hole transport materials with spiro-cores, i.e. Spiro-F1, Spiro-F2 and Spiro-F3, are investigated by using density functional theory combined with the Marcus theory and Einstein relation. Based on the calculated and experimental highest occupied molecular orbital (HOMO) levels of 30 reference molecules, an empirical equation, which can predict the HOMO levels of hole transport materials accurately, is proposed. Moreover, a simplified method, in which the hole transport pathways are simplified to be one-dimensional, is presented and adopted to qualitatively compare the molecular hole mobilities. The calculated results show that the perovskite solar cells with the new hole transport materials can have higher open-circuit voltages due to the lower HOMO levels of Spiro-F1 (-5.31 eV), Spiro-F2 (-5.42 eV) and Spiro-F3 (-5.10 eV) compared with that of Spiro-OMeTAD (-5.09 eV). Furthermore, the hole mobilities of Spiro-F1 (1.75 × 10-2 cm2 V-1 s-1) and Spiro-F3 (7.59 × 10-3 cm2 V-1 s-1) are 3.1 and 1.4 times that of Spiro-OMeTAD (5.65 × 10-3 cm2 V-1 s-1) respectively, due to small reorganization energies and large transfer integrals. Interestingly, the stability properties of Spiro-F1 and Spiro-F2 are shown to be comparable to that of Spiro-OMeTAD, and the dimers of Spiro-F2 and Spiro-F3 possess better stability than that of Spiro-OMeTAD. Taking into consideration the appropriate HOMO level, improved hole mobility and enhanced stability, Spiro-F1 and Spiro-F3 may become the most promising alternatives to Spiro-OMeTAD. The present work offers a new design strategy and reliable calculation methods towards the development of excellent organic small molecules as HTMs for highly efficient and stable PSCs.Perovskite solar cells (PSCs) with organic

  14. Protective relay principles

    CERN Document Server

    Sleva, Anthony F

    2009-01-01

    This title lets you improve failure detection and optimize protection. In the ever-evolving field of protective relay technology, an engineer's personal preference and professional judgment are as important to power system protection as the physical relays used to detect and isolate abnormal conditions. With invaluable insights from an experienced expert, ""Protective Relay Principles"" focuses on probable power system failure modes and the important characteristics of the protective relays used to detect these postulated failures.This book presents useful new concepts in a way that is easier

  15. Principles of fluorescence techniques

    CERN Document Server

    2016-01-01

    Fluorescence techniques are being used and applied increasingly in academics and industry. The Principles of Fluorescence Techniques course will outline the basic concepts of fluorescence techniques and the successful utilization of the currently available commercial instrumentation. The course is designed for students who utilize fluorescence techniques and instrumentation and for researchers and industrial scientists who wish to deepen their knowledge of fluorescence applications. Key scientists in the field will deliver theoretical lectures. The lectures will be complemented by the direct utilization of steady-state and lifetime fluorescence instrumentation and confocal microscopy for FLIM and FRET applications provided by leading companies.

  16. RFID design principles

    CERN Document Server

    Lehpamer, Harvey

    2012-01-01

    This revised edition of the Artech House bestseller, RFID Design Principles, serves as an up-to-date and comprehensive introduction to the subject. The second edition features numerous updates and brand new and expanded material on emerging topics such as the medical applications of RFID and new ethical challenges in the field. This practical book offers you a detailed understanding of RFID design essentials, key applications, and important management issues. The book explores the role of RFID technology in supply chain management, intelligent building design, transportation systems, military

  17. Principles of electromagnetic theory

    International Nuclear Information System (INIS)

    This book emphasizes the fundamental understanding of the laws governing the behavior of charge and current carrying bodies. Electromagnetism is presented as a classical theory, based-like mechanics-on principles that are independent of the atomic constitution of matter. This book is unique among electromagnetic texts in its treatment of the precise manner in which electromagnetism is linked to mechanics and thermodynamics. Applications include electrostriction, piezoelectricity, ferromagnetism, superconductivity, thermoelectricity, magnetohydrodynamics, radiation from charged particles, electromagnetic wave propagation and guided waves. There are many worked examples of dynamical and thermal effects of electromagnetic fields, and of effects resulting from the motion of bodies

  18. Principles of thermodynamics

    CERN Document Server

    Kaufman, Myron

    2002-01-01

    Ideal for one- or two-semester courses that assume elementary knowledge of calculus, This text presents the fundamental concepts of thermodynamics and applies these to problems dealing with properties of materials, phase transformations, chemical reactions, solutions and surfaces. The author utilizes principles of statistical mechanics to illustrate key concepts from a microscopic perspective, as well as develop equations of kinetic theory. The book provides end-of-chapter question and problem sets, some using Mathcad™ and Mathematica™; a useful glossary containing important symbols, definitions, and units; and appendices covering multivariable calculus and valuable numerical methods.

  19. Principles of quantum chemistry

    CERN Document Server

    George, David V

    2013-01-01

    Principles of Quantum Chemistry focuses on the application of quantum mechanics in physical models and experiments of chemical systems.This book describes chemical bonding and its two specific problems - bonding in complexes and in conjugated organic molecules. The very basic theory of spectroscopy is also considered. Other topics include the early development of quantum theory; particle-in-a-box; general formulation of the theory of quantum mechanics; and treatment of angular momentum in quantum mechanics. The examples of solutions of Schroedinger equations; approximation methods in quantum c

  20. Principles of meteoritics

    CERN Document Server

    Krinov, E L

    1960-01-01

    Principles of Meteoritics examines the significance of meteorites in relation to cosmogony and to the origin of the planetary system. The book discusses the science of meteoritics and the sources of meteorites. Scientists study the morphology of meteorites to determine their motion in the atmosphere. The scope of such study includes all forms of meteorites, the circumstances of their fall to earth, their motion in the atmosphere, and their orbits in space. Meteoric bodies vary in sizes; in calculating their motion in interplanetary space, astronomers apply the laws of Kepler. In the region of

  1. Principles of Uncertainty

    CERN Document Server

    Kadane, Joseph B

    2011-01-01

    An intuitive and mathematical introduction to subjective probability and Bayesian statistics. An accessible, comprehensive guide to the theory of Bayesian statistics, Principles of Uncertainty presents the subjective Bayesian approach, which has played a pivotal role in game theory, economics, and the recent boom in Markov Chain Monte Carlo methods. Both rigorous and friendly, the book contains: Introductory chapters examining each new concept or assumption Just-in-time mathematics -- the presentation of ideas just before they are applied Summary and exercises at the end of each chapter Discus

  2. Principles of copula theory

    CERN Document Server

    Durante, Fabrizio

    2015-01-01

    Principles of Copula Theory explores the state of the art on copulas and provides you with the foundation to use copulas in a variety of applications. Throughout the book, historical remarks and further readings highlight active research in the field, including new results, streamlined presentations, and new proofs of old results.After covering the essentials of copula theory, the book addresses the issue of modeling dependence among components of a random vector using copulas. It then presents copulas from the point of view of measure theory, compares methods for the approximation of copulas,

  3. Principles of sustainable energy

    CERN Document Server

    Kreith, Frank; Kreider, Jan F

    2010-01-01

    A transition from a fossil fuel-based economy to one that uses renewable energy has become inevitable; this transition will not only be an engineering challenge, but will also be an economic and environmental one. Offering an interdisciplinary, quantitative approach, Principles of Sustainable Energy presents a comprehensive overview of the major renewable energy technologies currently available, including biomass and biofuels, solar thermal conversion, photovoltaics, and wind energy conversion. Written by renowned expert Frank Kreith, the book emphasizes economics as well as energy return on i

  4. Principles of lithography

    CERN Document Server

    Levinson, Harry J

    2011-01-01

    The publication of Principles of Lithography, Third Edition just five years after the previous edition is evidence of the quickly changing and exciting nature of lithography as applied to the production of integrated circuits and other micro- and nanoscale devices. This text is intended to serve as an introduction to the science of microlithography, but also covers several subjects in depth, making it useful to the experienced lithographer as well. Topics directly related to manufacturing tools are addressed, including overlay, the stages of exposure, tools, and light sources. This updated edi

  5. Euphemism and the Politeness Principle

    Institute of Scientific and Technical Information of China (English)

    杨馥榕

    2014-01-01

    In linguistic communication, euphemism is a lubricant, whereas the politeness principle is a norm of moderating lin⁃guistic behavior. This paper aims to analyze the euphemism and the politeness principle, showing the relationship between euphe⁃mism and the politeness principle. In order to help people know how to behave in the daily communication and make their talk more effective.

  6. Archimedes' Principle in General Coordinates

    Science.gov (United States)

    Ridgely, Charles T.

    2010-01-01

    Archimedes' principle is well known to state that a body submerged in a fluid is buoyed up by a force equal to the weight of the fluid displaced by the body. Herein, Archimedes' principle is derived from first principles by using conservation of the stress-energy-momentum tensor in general coordinates. The resulting expression for the force is…

  7. Tailoring common treatment principles to fit individual personalities.

    Science.gov (United States)

    Critchfield, Kenneth L

    2012-02-01

    The American Psychological Association Task Force headed by Castonguay and Beutler (2006) distilled general treatment principles common to all therapies from the empirical literature. As part of this work, Critchifield and Benjamin (2006a, 2006b) summarized principles for treatment of personality disorder. The principles are pragmatic in the sense that they are based on evidence of what works, and clinicians are encouraged to apply them in ways that fit the unique presentation and needs of a given patient. An important element of the recommended approach is that it be coherent, well-coordinated, and agreed upon by the patient. Additional principles emphasize the importance of an individual's attachment and trauma history. A complex case example is presented to illustrate one way in which emphasis on an individual's relational learning history can be used to further refine and extend wisdom inherent in the cross-cutting principles and move in the direction of an integrative treatment that is closely tailored to specific case features. A research approach is also outlined for how to test the validity of principles that prescribe differential use of technique to address diverse patient presentations. PMID:22369169

  8. Plastic variational principle based on the least work consumption principle

    Institute of Scientific and Technical Information of China (English)

    唐松花; 罗迎社; 周筑宝; 王智超

    2008-01-01

    Plastic variational principles are foundation to solve the boundary-value problems of plastic mechanics with the variational method(or energy method) and finite element method.The most convenient way of establishing different kinds of variational principles is to set up the extreme principle related to the studied problem.Based on a general new extreme principle-the Least work consumption principle,the variational principles of the rigid-plastic and rigid-viscoplastic material were derived.In comparison with existing methods,the method in this paper is more clear and direct,and the physical meaning is clear-cut.This method can offer a new way for establishing other kinds of variational principles.

  9. Indian Physics: Outline of Early History

    CERN Document Server

    Kak, S

    2003-01-01

    Historians of science are generally unaware of the contributions of India to physics. The main reason for this is that very little research has been done on the subject in the recent past, a consequence of the fact that there are few history of science departments in Indian universities. The objective of this paper is to present a preliminary outline of early history of physics in India. The schools of Vaisheshika and Samkhya, that were interested in general principles of atomic theory and cosmology, are discussed. In particular, ideas on atoms and molecules, the nature of sound, causality, universals, cosmology, uniform and non-uniform motions are described.

  10. Principles of Mechanical Excavation

    International Nuclear Information System (INIS)

    Mechanical excavation of rock today includes several methods such as tunnel boring, raiseboring, roadheading and various continuous mining systems. Of these raiseboring is one potential technique for excavating shafts in the repository for spent nuclear fuel and dry blind boring is promising technique for excavation of deposition holes, as demonstrated in the Research Tunnel at Olkiluoto. In addition, there is potential for use of other mechanical excavation techniques in different parts of the repository. One of the main objectives of this study was to analyze the factors which affect the feasibility of mechanical rock excavation in hard rock conditions and to enhance the understanding of factors which affect rock cutting so as to provide an improved basis for excavator performance prediction modeling. The study included the following four main topics: (a) phenomenological model based on similarity analysis for roller disk cutting, (b) rock mass properties which affect rock cuttability and tool life, (c) principles for linear and field cutting tests and performance prediction modeling and (d) cutter head lacing design procedures and principles. As a conclusion of this study, a test rig was constructed, field tests were planned and started up. The results of the study can be used to improve the performance prediction models used to assess the feasibility of different mechanical excavation techniques at various repository investigation sites. (orig.)

  11. Principles of Mechanical Excavation

    Energy Technology Data Exchange (ETDEWEB)

    Lislerud, A. [Tamrock Corp., Tampere (Finland)

    1997-12-01

    Mechanical excavation of rock today includes several methods such as tunnel boring, raiseboring, roadheading and various continuous mining systems. Of these raiseboring is one potential technique for excavating shafts in the repository for spent nuclear fuel and dry blind boring is promising technique for excavation of deposition holes, as demonstrated in the Research Tunnel at Olkiluoto. In addition, there is potential for use of other mechanical excavation techniques in different parts of the repository. One of the main objectives of this study was to analyze the factors which affect the feasibility of mechanical rock excavation in hard rock conditions and to enhance the understanding of factors which affect rock cutting so as to provide an improved basis for excavator performance prediction modeling. The study included the following four main topics: (a) phenomenological model based on similarity analysis for roller disk cutting, (b) rock mass properties which affect rock cuttability and tool life, (c) principles for linear and field cutting tests and performance prediction modeling and (d) cutter head lacing design procedures and principles. As a conclusion of this study, a test rig was constructed, field tests were planned and started up. The results of the study can be used to improve the performance prediction models used to assess the feasibility of different mechanical excavation techniques at various repository investigation sites. (orig.). 21 refs.

  12. THE RESPONSIBILITY PRINCIPLE

    Directory of Open Access Journals (Sweden)

    Elena ANGHEL

    2015-07-01

    Full Text Available "I'm wishing Law this: all legal obligations sholud be executed with the scrupulosity with which moral obligations are being performed by those people who feel bound by them ...", so beautifully portraited by Nicolae Titulescu`s words1. Life in the society means more than a simple coexistence of human beings, it actually means living together, collaborating and cooperating; that is why I always have to relate to other people and to be aware that only by limiting my freedom of action, the others freedom is feasible. Neminem laedere should be a principle of life for each of us. The individual is a responsible being. But responsibility exceeds legal prescriptions. Romanian Constitution underlines that I have to exercise my rights and freedoms in good faith, without infringing the rights and freedoms of others. The legal norm, developer of the constitutional principles, is endowed with sanction, which grants it exigibility. But I wonder: If I choose to obey the law, is my decision essentially determined only due of the fear of punishment? Is it not because I am a rational being, who developed during its life a conscience towards values, and thus I understand that I have to respect the law and I choose to comply with it?

  13. Chemical History with a Nuclear Microprobe

    OpenAIRE

    Maggiore, C. J.; Benjamin, T. M.; Hyde, P. J.; Rogers, P. S. Z.; Srinivasan, S; Tesmer, J.; Woolum, D. S.; Burnett, D. S.

    1983-01-01

    A nuclear microprobe cannot give direct information on the chemical state of an element, but the spatial distribution of elements in a specimen is often determined by the chemical history of the sample. Fuel cells and minerals are examples of complex systems whose elemental distributions are determined by past chemical history. The distribution of catalyst in used fuel cell electrodes provides direct information on the chemical stability of dispersed catalysts under operating conditions. We h...

  14. Principles of Quantum Mechanics

    Science.gov (United States)

    Landé, Alfred

    2013-10-01

    Preface; Introduction: 1. Observation and interpretation; 2. Difficulties of the classical theories; 3. The purpose of quantum theory; Part I. Elementary Theory of Observation (Principle of Complementarity): 4. Refraction in inhomogeneous media (force fields); 5. Scattering of charged rays; 6. Refraction and reflection at a plane; 7. Absolute values of momentum and wave length; 8. Double ray of matter diffracting light waves; 9. Double ray of matter diffracting photons; 10. Microscopic observation of ρ (x) and σ (p); 11. Complementarity; 12. Mathematical relation between ρ (x) and σ (p) for free particles; 13. General relation between ρ (q) and σ (p); 14. Crystals; 15. Transition density and transition probability; 16. Resultant values of physical functions; matrix elements; 17. Pulsating density; 18. General relation between ρ (t) and σ (є); 19. Transition density; matrix elements; Part II. The Principle of Uncertainty: 20. Optical observation of density in matter packets; 21. Distribution of momenta in matter packets; 22. Mathematical relation between ρ and σ; 23. Causality; 24. Uncertainty; 25. Uncertainty due to optical observation; 26. Dissipation of matter packets; rays in Wilson Chamber; 27. Density maximum in time; 28. Uncertainty of energy and time; 29. Compton effect; 30. Bothe-Geiger and Compton-Simon experiments; 31. Doppler effect; Raman effect; 32. Elementary bundles of rays; 33. Jeans' number of degrees of freedom; 34. Uncertainty of electromagnetic field components; Part III. The Principle of Interference and Schrödinger's equation: 35. Physical functions; 36. Interference of probabilities for p and q; 37. General interference of probabilities; 38. Differential equations for Ψp (q) and Xq (p); 39. Differential equation for фβ (q); 40. The general probability amplitude Φβ' (Q); 41. Point transformations; 42. General theorem of interference; 43. Conjugate variables; 44. Schrödinger's equation for conservative systems; 45. Schr

  15. Non-invasive detection of genomic imbalances in Hodgkin/Reed-Sternberg cells in early and advanced stage Hodgkin's lymphoma by sequencing of circulating cell-free DNA: a technical proof-of-principle study

    OpenAIRE

    Vandenberghe, Peter; Wlodarska, Iwona; Tousseyn, Thomas; Dehaspe, Luc; Dierickx, Daan; Verheecke, Magali; Uyttebroeck, Anne; Bechter, Oliver; Delforge, Michel; Vandecaveye, Vincent; Brison, Nathalie; Verhoef, Gregor; Legius, Eric; Amant, Frédéric; Vermeesch, Joris

    2015-01-01

    Hodgkin's lymphoma is one of the most common lymphoid neoplasms in young adults, but the low abundance of neoplastic Hodgkin/Reed-Sternberg cells in the tumour hampers the elucidation of its pathogenesis, biology, and diversity. After an incidental observation that genomic aberrations known to occur in Hodgkin's lymphoma were detectable in circulating cell-free DNA, this study was undertaken to investigate whether circulating cell-free DNA can be informative about genomic imbalances in Hodgki...

  16. Politeness Principle and Intercultural Communication

    Institute of Scientific and Technical Information of China (English)

    周宇岚

    2007-01-01

    There are many potential problems in intercultural communications.Politeness principle is very important in helping improving intercultural communications.But different cultures have various standard of politeness principle.This essay discusses the very different points of view on politeness principle between Chinese people and westerners,and studies how the context and settings affect the practice of politeness principle.At the ending of the essay,the guiding significance of politeness principle is pointed out.And it also points out seeking common understanding of various cultures.In some aspects,this paper is useful for effective intercultural communications.

  17. Solar energy: principles and possibilities.

    Science.gov (United States)

    Rhodes, Christopher J

    2010-01-01

    As the world faces an impending dearth of fossil fuels, most immediately oil, alternative sources of energy must be found. 174 PW worth of energy falls onto the top of the Earth's atmosphere in the form of sunlight which is almost 10,000 times the total amount of energy used by humans on Earth, as taken from all sources, oil, coal, natural gas, nuclear and hydroelectric power combined. If even a fraction of this could be harvested efficiently, the energy crunch could in principle be averted. Various means for garnering energy from the Sun are presented, including photovoltaics (PV), thin film solar cells, quantum dot cells, concentrating PV and thermal solar power stations, which are more efficient in practical terms. Finally the prospects of space based (satellite) solar power are considered. The caveat is that even if the entire world electricity budget could be met using solar energy, the remaining 80% of energy which is not used as electricity but thermal power (heat) still needs to be found in the absence of fossil fuels. Most pressingly, the decline of cheap plentiful crude oil (peak oil) will not find a substitution via solar unless a mainly electrified transportation system is devised and it is debatable that there is sufficient time and conventional energy remaining to accomplish this. The inevitable contraction of transportation will default a deconstruction of the globalised world economy into that of a system of localised communities. PMID:20222355

  18. The principle of life

    International Nuclear Information System (INIS)

    The chapters ''History of the movement'', ''How war against man relates to war against the environment'', ''The hurdles'', ''The strategic controversy'' point out that the slow death of mankind by the destruction of the conditions of life is certain, the sudden one by a nuclear war probable. This, of course, applies only to those who have not fallen victim to starvation before. It is something everybody knows, especially there ''in change''; yet the old jog-trot is going on. The book reports how people who fear the worst are forming a new power and advocating a change. The battle is about new majorities that have to be won. (orig./HSCH)

  19. History of Bioterrorism: Botulism

    Medline Plus

    Full Text Available ... Guide Reaching At-Risk Populations MedCon Video: "The History of Bioterrorism" Recommend on Facebook Tweet Share Compartir ... as bioterrorist weapons. Watch the Complete Program "The History of Bioterroism" (26 min 38 sec) Watch Specific ...

  20. Essays in History & Finance

    OpenAIRE

    D'ACUNTO, FRANCESCO

    2015-01-01

    To which extent may history help us understand current financial outcomes? FinancialHistory typically tests for financial theories using historical data, or studies past financialoutcomes to understand the present through analogy. This dissertation focuses on an alternative approach to the use of history in finance, which I label "History & Finance." This approach exploits facts and institutions of the past, and the persistence of the economic and social phenomena they determine, to directly...

  1. Canadian petroleum history bibliography

    Energy Technology Data Exchange (ETDEWEB)

    Cass, D.

    2003-09-27

    The Petroleum History Bibliography includes a list of more than 2,000 publications that record the history of the Canadian petroleum industry. The list includes books, theses, films, audio tapes, published articles, company histories, biographies, autobiographies, fiction, poetry, humour, and an author index. It was created over a period of several years to help with projects at the Petroleum History Society. It is an ongoing piece of work, and as such, invites comments and additions.

  2. Critical reflections on the principle of beneficence in biomedicine.

    Science.gov (United States)

    Munyaradzi, Mawere

    2012-01-01

    Medical ethics as a scholarly discipline and a system of moral principles that apply values and judgments to the practice of medicine encompasses its practical application in clinical settings as well as work on its history, philosophy, theology, anthropology and sociology. As such there are a number of values in medical ethics such as autonomy, non-maleficence, confidentiality, dignity, honesty, justice and beneficence, among others. These values act as guidelines for professionals in the medical fraternity and are therefore used to judge different cases in the fraternity. For purposes of this work, this paper examines the principle of beneficence in biomedicine. Using both hypothetical cases and others in real life situations, the paper reflects on the implications of beneficence in biomedicine. It argues that the principle of beneficence is a prima facie obligation that should "always be acted upon unless it conflicts on a particular occasion with an equal or stronger principle". PMID:22514763

  3. Teaching history-taking: where are we?

    OpenAIRE

    Nardone, D. A.; Reuler, J B; Girard, D. E.

    1980-01-01

    Knowledge in history-taking has increased rapidly over the last twenty years. Currently the principles to be taught include "conduct," "content," and "diagnostic reasoning." However, inattentiveness of medical schools, reluctance of busy faculty to be involved, and increasing enrollments have resulted in difficulties in teaching these skills. Studies have shown a beneficial short-term effect of teaching these materials on interview performance but it is unknown whether this effect is long-las...

  4. The Age of porno-History

    OpenAIRE

    Darragon, Eric

    2012-01-01

    The discourse on the body is not exactly new, but it has gained a kind of ascendancy in matters of aesthetics, especially where university art history and criticism are concerned. Hence the visible changes in methods and formulations. After much water under the bridge, the question of art is paradoxically back in statu nascendi, insofar as its principle is being extended without faltering to new approaches and objects. When he explored the idea of the “artification” of experience in 1978, Ala...

  5. Principles of modern physics

    CERN Document Server

    Saxena, A K

    2014-01-01

    Principles of Modern Physics, divided into twenty one chapters, begins with quantum ideas followed by discussions on special relativity, atomic structure, basic quantum mechanics, hydrogen atom (and Schrodinger equation) and periodic table, the three statistical distributions, X-rays, physics of solids, imperfections in crystals, magnetic properties of materials, superconductivity, Zeeman-, Stark- and Paschen Back- effects, Lasers, Nuclear physics (Yukawa's meson theory and various nuclear models), radioactivity and nuclear reactions, nuclear fission, fusion and plasma, particle accelerators and detectors, the universe, Elementary particles (classification, eight fold way and quark model, standard model and fundamental interactions), cosmic rays, deuteron problem in nuclear physics, and cathode ray oscilloscope. NEW TO THE FOURTH EDITION: The CO2 Laser Theory of magnetic moments on the basis of shell model Geological dating Laser Induced fusion and laser fusion reactor. Hawking radiation The cosmological red ...

  6. Emulsion Science Basic Principles

    CERN Document Server

    Leal-Calderon, Fernando; Schmitt, Véronique

    2007-01-01

    Emulsions are generally made out of two immiscible fluids like oil and water, one being dispersed in the second in the presence of surface-active compounds.They are used as intermediate or end products in a huge range of areas including the food, chemical, cosmetic, pharmaceutical, paint, and coating industries. Besides the broad domain of technological interest, emulsions are raising a variety of fundamental questions at the frontier between physics and chemistry. This book aims to give an overview of the most recent advances in emulsion science. The basic principles, covering aspects of emulsions from their preparation to their destruction, are presented in close relation to both the fundamental physics and the applications of these materials. The book is intended to help scientists and engineers in formulating new materials by giving them the basics of emulsion science.

  7. Principles of Lasers

    CERN Document Server

    Svelto, Orazio

    2010-01-01

    This new Fifth Edition of Principles of Lasers incorporates corrections to the previous edition. The text’s essential mission remains the same: to provide a wide-ranging yet unified description of laser behavior, physics, technology, and current applications. Dr. Svelto emphasizes the physical rather than the mathematical aspects of lasers, and presents the subject in the simplest terms compatible with a correct physical understanding. Praise for earlier editions: "Professor Svelto is himself a longtime laser pioneer and his text shows the breadth of his broad acquaintance with all aspects of the field … Anyone mastering the contents of this book will be well prepared to understand advanced treatises and research papers in laser science and technology." (Arthur L. Schawlow, 1981 Nobel Laureate in Physics) "Already well established as a self-contained introduction to the physics and technology of lasers … Professor Svelto’s book, in this lucid translation by David Hanna, can be strongly recommended for...

  8. Kepler and Mach's Principle

    Science.gov (United States)

    Barbour, Julian

    The definitive ideas that led to the creation of general relativity crystallized in Einstein's thinking during 1912 while he was in Prague. At the centenary meeting held there to mark the breakthrough, I was asked to talk about earlier great work of relevance to dynamics done at Prague, above all by Kepler and Mach. The main topics covered in this chapter are: some little known but basic facts about the planetary motions; the conceptual framework and most important discoveries of Ptolemy and Copernicus; the complete change of concepts that Kepler introduced and their role in his discoveries; the significance of them in Newton's work; Mach's realization that Kepler's conceptual revolution needed further development to free Newton's conceptual world of the last vestiges of the purely geometrical Ptolemaic world view; and the precise formulation of Mach's principle required to place GR correctly in the line of conceptual and technical evolution that began with the ancient Greek astronomers.

  9. Principles & practice of physics

    CERN Document Server

    Mazur, Eric; Dourmashkin, Peter A; Pedigo, Daryl; Bieniek, Ronald J

    2015-01-01

    Putting physics first Based on his storied research and teaching, Eric Mazur's Principles & Practice of Physics builds an understanding of physics that is both thorough and accessible. Unique organization and pedagogy allow you to develop a true conceptual understanding of physics alongside the quantitative skills needed in the course. *New learning architecture: The book is structured to help you learn physics in an organized way that encourages comprehension and reduces distraction.*Physics on a contemporary foundation: Traditional texts delay the introduction of ideas that we now see as unifying and foundational. This text builds physics on those unifying foundations, helping you to develop an understanding that is stronger, deeper, and fundamentally simpler.*Research-based instruction: This text uses a range of research-based instructional techniques to teach physics in the most effective manner possible. The result is a groundbreaking book that puts physics first, thereby making it more accessible to...

  10. Conducting the Medical History

    Science.gov (United States)

    Finkel, Martin A.; Alexander, Randell A.

    2011-01-01

    A key portion of the medical evaluation of child sexual abuse is the medical history. This differs from interviews or histories obtained by other professionals in that it is focuses more on the health and well-being of the child. Careful questions should be asked about all aspects of the child's medical history by a skilled, compassionate,…

  11. Studying Ancient History.

    Science.gov (United States)

    Barrow, Robin

    1982-01-01

    Defends the value and relevance of the study of ancient history and classics in history curricula. The unique homogeneity of the classical period contributes to its instructional manageability. A year-long, secondary-level course on fifth-century Greece and Rome is described to illustrate effective approaches to teaching ancient history. (AM)

  12. Modern History of Tibet

    Institute of Scientific and Technical Information of China (English)

    2005-01-01

    Authored by Xu Guangzhi, this book is a subsidiary project of Research Into Traditional Culture and History (of the PRC Ministry of Education) conducted by China Tibetology Research Institute of Tibet University. The book combines modern history of Tibet with modern history of China as a whole. It tells the close ties between various members of the Chinese nation.

  13. Fault Management Guiding Principles

    Science.gov (United States)

    Newhouse, Marilyn E.; Friberg, Kenneth H.; Fesq, Lorraine; Barley, Bryan

    2011-01-01

    Regardless of the mission type: deep space or low Earth orbit, robotic or human spaceflight, Fault Management (FM) is a critical aspect of NASA space missions. As the complexity of space missions grows, the complexity of supporting FM systems increase in turn. Data on recent NASA missions show that development of FM capabilities is a common driver for significant cost overruns late in the project development cycle. Efforts to understand the drivers behind these cost overruns, spearheaded by NASA's Science Mission Directorate (SMD), indicate that they are primarily caused by the growing complexity of FM systems and the lack of maturity of FM as an engineering discipline. NASA can and does develop FM systems that effectively protect mission functionality and assets. The cost growth results from a lack of FM planning and emphasis by project management, as well the maturity of FM as an engineering discipline, which lags behind the maturity of other engineering disciplines. As a step towards controlling the cost growth associated with FM development, SMD has commissioned a multi-institution team to develop a practitioner's handbook representing best practices for the end-to-end processes involved in engineering FM systems. While currently concentrating primarily on FM for science missions, the expectation is that this handbook will grow into a NASA-wide handbook, serving as a companion to the NASA Systems Engineering Handbook. This paper presents a snapshot of the principles that have been identified to guide FM development from cradle to grave. The principles range from considerations for integrating FM into the project and SE organizational structure, the relationship between FM designs and mission risk, and the use of the various tools of FM (e.g., redundancy) to meet the FM goal of protecting mission functionality and assets.

  14. Diet History Questionnaire: Database Revision History

    Science.gov (United States)

    The following details all additions and revisions made to the DHQ nutrient and food database. This revision history is provided as a reference for investigators who may have performed analyses with a previous release of the database.

  15. Essential operating principles for tumor spheroid growth

    OpenAIRE

    Ropella Glen EP; Engelberg Jesse A; Hunt C Anthony

    2008-01-01

    Abstract Background Our objective was to discover in silico axioms that are plausible representations of the operating principles realized during characteristic growth of EMT6/Ro mouse mammary tumor spheroids in culture. To reach that objective we engineered and iteratively falsified an agent-based analogue of EMT6 spheroid growth. EMT6 spheroids display consistent and predictable growth characteristics, implying that individual cell behaviors are tightly controlled and regulated. An approach...

  16. The principles of cryostratigraphy

    Science.gov (United States)

    French, Hugh; Shur, Yuri

    2010-08-01

    Cryostratigraphy adopts concepts from both Russian geocryology and modern sedimentology. Structures formed by the amount and distribution of ice within sediment and rock are termed cryostructures. Typically, layered cryostructures are indicative of syngenetic permafrost while reticulate and irregular cryostructures are indicative of epigenetic permafrost. 'Cryofacies' can be defined according to patterns of sediment characterized by distinct ice lenses and layers, volumetric ice content and ice-crystal size. Cryofacies can be subdivided according to cryostructure. Where a number of cryofacies form a distinctive cryostratigraphic unit, these are termed a 'cryofacies assemblage'. The recognition, if present, of (i) thaw unconformities, (ii) other ice bodies such as vein ice (ice wedges), aggradational ice and thermokarst-cave ('pool') ice, and (iii) ice, sand and gravelly pseudomorphs is also important in determining the nature of the freezing process, the conditions under which frozen sediment accumulates, and the history of permafrost.

  17. Principles of magnetostatics

    CERN Document Server

    Fernow, Richard C

    2016-01-01

    The subject of magnetostatics - the mathematical theory that describes the forces and fields resulting from the steady flow of electrical currents - has a long history. By capturing the basic concepts, and building towards the computation of magnetic fields, this book is a self-contained discussion of the major subjects in magnetostatics. Overviews of Maxwell's equations, the Poisson equation, and boundary value problems pave the way for dealing with fields from transverse, axial and periodic magnetic arrangements and assemblies of permanent magnets. Examples from accelerator and beam physics give up-to-date context to the theory. Furthermore, both complex contour integration and numerical techniques (including finite difference, finite element, and integral equation methods) for calculating magnetic fields are discussed in detail with plentiful examples. Both theoretical and practical information on carefully selected topics make this a one-stop reference for magnet designers, as well as for physics and elec...

  18. Archimedes' principle in general coordinates

    International Nuclear Information System (INIS)

    Archimedes' principle is well known to state that a body submerged in a fluid is buoyed up by a force equal to the weight of the fluid displaced by the body. Herein, Archimedes' principle is derived from first principles by using conservation of the stress-energy-momentum tensor in general coordinates. The resulting expression for the force is applied in Schwarzschild coordinates and in rotating coordinates. Using Schwarzschild coordinates for the case of a spherical mass suspended within a perfect fluid leads to the familiar expression of Archimedes' principle. Using rotating coordinates produces an expression for a centrifugal buoyancy force that agrees with accepted theory. It is then argued that Archimedes' principle ought to be applicable to non-gravitational phenomena, as well. Conservation of the energy-momentum tensor is then applied to electromagnetic phenomena. It is shown that a charged body submerged in a charged medium experiences a buoyancy force in accordance with an electromagnetic analogue of Archimedes' principle.

  19. PRINCIPLES AND PROCEDURES ON FISCAL

    OpenAIRE

    Morar Ioan Dan

    2011-01-01

    Fiscal science advertise in most analytical situations, while the principles reiterated by specialists in the field in various specialized works. The two components of taxation, the tax system relating to the theoretical and the practical procedures relating to tax are marked by frequent references and invocations of the underlying principles to tax. This paper attempts a return on equity fiscal general vision as a principle often invoked and used to justify tax policies, but so often violate...

  20. Pedagogical Principles in Online Teaching

    DEFF Research Database (Denmark)

    Beckmann, Suzanne C.; Uth Thomsen, Thyra; von Wallpach, Sylvia

    the seven pedagogical principles that govern the teaching at our university. We also present a case study that illustrates how both opportunities and challenges were met in two “first-mover” fully online courses during Fall 2014. The experiences from this case study are discussed in terms of to what...... extent they met the pedagogical principles and observations unrelated to the pedagogical principle are shared....

  1. Electrodynamics basics and duality principle

    OpenAIRE

    Ivanitckiy, A. M.

    2014-01-01

    The given report proposes general and consistent statement of the classical electrodynamics basis using axiomatic and duality principles for its construct. Vector algebra and vector analysis are created by the application of the duality principle. The last fact allows formulating Maxwell equations in strictly symmetric form. It means the statement of electrodynamics postulates (axioms) under a principle of duality. Electrodynamics basis construction begins immediately using its postulates for...

  2. Principles of alternative gerontology.

    Science.gov (United States)

    Bilinski, Tomasz; Bylak, Aneta; Zadrag-Tecza, Renata

    2016-04-01

    Surveys of taxonomic groups of animals have shown that contrary to the opinion of most gerontologists aging is not a genuine trait. The process of aging is not universal and its mechanisms have not been widely conserved among species. All life forms are subject to extrinsic and intrinsic destructive forces. Destructive effects of stochastic events are visible only when allowed by the specific life program of an organism. Effective life programs of immortality and high longevity eliminate the impact of unavoidable damage. Organisms that are capable of agametic reproduction are biologically immortal. Mortality of an organism is clearly associated with terminal specialisation in sexual reproduction. The longevity phenotype that is not accompanied by symptoms of senescence has been observed in those groups of animals that continue to increase their body size after reaching sexual maturity. This is the result of enormous regeneration abilities of both of the above-mentioned groups. Senescence is observed when: (i) an organism by principle switches off the expression of existing growth and regeneration programs, as in the case of imago formation in insect development; (ii) particular programs of growth and regeneration of progenitors are irreversibly lost, either partially or in their entirety, in mammals and birds. PMID:27017907

  3. Principles of Bioremediation Assessment

    Science.gov (United States)

    Madsen, E. L.

    2001-12-01

    Although microorganisms have successfully and spontaneously maintained the biosphere since its inception, industrialized societies now produce undesirable chemical compounds at rates that outpace naturally occurring microbial detoxification processes. This presentation provides an overview of both the complexities of contaminated sites and methodological limitations in environmental microbiology that impede the documentation of biodegradation processes in the field. An essential step toward attaining reliable bioremediation technologies is the development of criteria which prove that microorganisms in contaminated field sites are truly active in metabolizing contaminants of interest. These criteria, which rely upon genetic, biochemical, physiological, and ecological principles and apply to both in situ and ex situ bioremediation strategies include: (i) internal conservative tracers; (ii) added conservative tracers; (iii) added radioactive tracers; (iv) added isotopic tracers; (v) stable isotopic fractionation patterns; (vi) detection of intermediary metabolites; (vii) replicated field plots; (viii) microbial metabolic adaptation; (ix) molecular biological indicators; (x) gradients of coreactants and/or products; (xi) in situ rates of respiration; (xii) mass balances of contaminants, coreactants, and products; and (xiii) computer modeling that incorporates transport and reactive stoichiometries of electron donors and acceptors. The ideal goal is achieving a quantitative understanding of the geochemistry, hydrogeology, and physiology of complex real-world systems.

  4. Magnetism: Principles and Applications

    Science.gov (United States)

    Craik, Derek J.

    2003-09-01

    If you are studying physics, chemistry, materials science, electrical engineering, information technology or medicine, then you'll know that understanding magnetism is fundamental to success in your studies and here is the key to unlocking the mysteries of magnetism....... You can: obtain a simple overview of magnetism, including the roles of B and H, resonances and special techniques take full advantage of modern magnets with a wealth of expressions for fields and forces develop realistic general design programmes using isoparametric finite elements study the subtleties of the general theory of magnetic moments and their dynamics follow the development of outstanding materials appreciate how magnetism encompasses topics as diverse as rock magnetism, chemical reaction rates, biological compasses, medical therapies, superconductivity and levitation understand the basis and remarkable achievements of magnetic resonance imaging In his new book, Magnetism, Derek Craik throws light on the principles and applications of this fascinating subject. From formulae for calculating fields to quantum theory, the secrets of magnetism are exposed, ensuring that whether you are a chemist or engineer, physicist, medic or materials scientist Magnetism is the book for our course.

  5. Advertisement without Ethical Principles?

    Directory of Open Access Journals (Sweden)

    Wojciech Słomski

    2007-10-01

    Full Text Available The article replies to the question, whether the advertisement can exist without ethical principles or ethics should be the basis of the advertisement. One can say that the ethical opinion of the advertisement does not depend on content and the form of advertising content exclusively, but also on recipients consciousness. The advertisement appeals to the emotions more than to the intellect, thus restricting the area of conscious and based on rational premises choice, so it is morally bad. It is not that the moral evil immanently underlines the advertisement, but it concerns the mechanisms which cause that the advertisement turns out to be effective. The only admissible form of the advertisement would be the reliable full information about the advantages and flaws of the concrete advertised product. The only admissible form of the advertisement would be the reliable full information about the advantages and defects of the concrete advertised product. The most serious difficulty connected with the ethical opinion of the advertisement is the fact that the advertisement is the indispensable link of the present economy, and everyone who accepts the free market and perceives the positives of the economic growth, should also accept the advertisement. The advertisement constitutes the element of the economic activity, so in consequence the responsibility first of all lies with enterprises for its far-reaching results.

  6. Great Lakes Literacy Principles

    Science.gov (United States)

    Fortner, Rosanne W.; Manzo, Lyndsey

    2011-03-01

    Lakes Superior, Huron, Michigan, Ontario, and Erie together form North America's Great Lakes, a region that contains 20% of the world's fresh surface water and is home to roughly one quarter of the U.S. population (Figure 1). Supporting a $4 billion sport fishing industry, plus $16 billion annually in boating, 1.5 million U.S. jobs, and $62 billion in annual wages directly, the Great Lakes form the backbone of a regional economy that is vital to the United States as a whole (see http://www.miseagrant.umich.edu/downloads/economy/11-708-Great-Lakes-Jobs.pdf). Yet the grandeur and importance of this freshwater resource are little understood, not only by people in the rest of the country but also by many in the region itself. To help address this lack of knowledge, the Centers for Ocean Sciences Education Excellence (COSEE) Great Lakes, supported by the U.S. National Science Foundation and the National Oceanic and Atmospheric Administration, developed literacy principles for the Great Lakes to serve as a guide for education of students and the public. These “Great Lakes Literacy Principles” represent an understanding of the Great Lakes' influences on society and society's influences on the Great Lakes.

  7. The iceberg principles

    CERN Document Server

    Spencer-Devlin, Marni

    2013-01-01

    The Iceberg Principles connect spirituality and science in a way that proves that the energy, which is the substance of the Universe, really is Love - not sweet, syrupy, candy-and-roses kind of love but the most powerful force in the Universe. Love without expression is meaningless. This is why the Big Bang was the only logical outcome. Love had to become reflected in dimensionality. With the Big Bang a 4:96 ratio was created between the dimensional and non-dimensional realms. This ratio between visibility and invisibility the ratio of an iceberg also applies to human beings. Only four percent of who we are is visible. Our physical DNA describes us but it does not define us. What defines us are our characteristics, our gifts, and talents - the spiritual DNA. This is invisible but makes up ninety-six percent of who we are. Our talents are not accidental; our life purpose is to express them. Just as the Universe emerges into dimensionality, constantly creating galaxies at millions of miles a minute, we are al...

  8. Continuous histories and the history group in generalised quantum theory

    CERN Document Server

    Linden, N

    1995-01-01

    We treat continuous histories within the histories approach to generalised quantum mechanics. The essential tool is the `history group': the analogue, within the generalised history scheme, of the canonical group of single-time quantum mechanics.

  9. Changes in sensitivity to radiation and to bleomycin occurring during the life history of monolayer cultures of a mouse tumour cell line

    International Nuclear Information System (INIS)

    The response to X-radiation and to bleomycin has been measured at a number of times during the life of monolayer cultures of EMT6 mouse tumour cells. Little change in radiation sensitivity was seen at any time and no loss of the shoulder to the survival curve occurred. Cultures in early plateau phase (where a considerable amount of cell proliferation is balanced by cell loss) showed a reduced sensitivity to bleomycin when compared with cells in exponential growth. However, after a longer period in plateau phase, when proliferation had virtually ceased, the sensitivity became greater than that of exponential phase cells. These findings are discussed with reference to the conflicting results of other workers. (author)

  10. TS-1 from First Principles

    Science.gov (United States)

    Gamba, Aldo; Tabacchi, Gloria; Fois, Ettore

    2009-09-01

    First principles studies on periodic TS-1 models at Ti content corresponding to 1.35% and 2.7% in weight of TiO2 are presented. The problem of Ti preferential siting is addressed by using realistic models corresponding to the TS-1 unit cell [TiSi95O192] and adopting for the first time a periodic DFT approach, thus providing an energy scale for Ti in the different crystallographic sites in nondefective TS-1. The structure with Ti in site T3 is the most stable, followed by T4 (+0.3 kcal/mol); the less stable structure, corresponding to Ti in T1, is 5.6 kcal/mol higher in energy. The work has been extended to investigate models with two Ti's per unit cell [Ti2Si94O192] (2.7%). The possible existence of Ti-O-Ti bridges, formed by two corner-sharing TiO4 tetrahedra, is discussed. By using cluster models cut from the optimized periodic DFT structures, both vibrational (DFT) and electronic excitation spectra (TDDFT) have been calculated and favorably compared with the experimental data available on TS-1. Interesting features emerged from excitation spectra: (i) Isolated tetrahedral Ti sites show a Beer-Lambert behavior, with absorption intensity proportional to concentration. Such a behavior is gradually lost when two Ti's occupy sites close to each other. (ii) The UV-vis absorption in the 200-250 nm region can be associated with transitions from occupied states delocalized on the framework oxygens to empty d states localized on Ti. Such extended-states-to-local-states transitions may help the interpretation of the photovoltaic activity recently detected in Ti zeolites.

  11. Principles of cryopreservation.

    Science.gov (United States)

    Pegg, David E

    2015-01-01

    Cryopreservation is the use of very low temperatures to preserve structurally intact living cells and tissues. Unprotected freezing is normally lethal and this chapter seeks to analyze some of the mechanisms involved and to show how cooling can be used to produce stable conditions that preserve life. The biological effects of cooling are dominated by the freezing of water, which results in the concentration of the solutes that are dissolved in the remaining liquid phase. Rival theories of freezing injury have envisaged either that ice crystals pierce or tease apart the cells, destroying them by direct mechanical action, or that damage is from secondary effects via changes in the composition of the liquid phase. Cryoprotectants, simply by increasing the total concentration of all solutes in the system, reduce the amount of ice formed at any given temperature; but to be biologically acceptable they must be able to penetrate into the cells and have low toxicity. Many compounds have such properties, including glycerol, dimethyl sulfoxide, ethanediol, and propanediol. In fact, both damaging mechanisms are important, their relative contributions depending on cell type, cooling rate, and warming rate. A consensus has developed that intracellular freezing is dangerous, whereas extracellular ice is harmless. If the water permeability of the cell membrane is known it is possible to predict the effect of cooling rate on cell survival and the optimum rate will be a trade-off between the risk of intracellular freezing and effects of the concentrated solutes. However, extracellular ice is not always innocuous: densely packed cells are more likely to be damaged by mechanical stresses within the channels where they are sequestered and with complex multicellular systems it is imperative not only to secure cell survival but also to avoid damage to the extracellular structure. Ice can be avoided by vitrification-the production of a glassy state that is defined by the viscosity

  12. Bone transplantation and tissue engineering, part IV. Mesenchymal stem cells: history in orthopedic surgery from Cohnheim and Goujon to the Nobel Prize of Yamanaka.

    Science.gov (United States)

    Hernigou, Philippe

    2015-04-01

    In 1867 the German pathologist Cohnheim hypothesized that non-hematopoietic, bone marrow-derived cells could migrate through the blood stream to distant sites of injury and participate in tissue regeneration. In 1868, the French physiologist Goujon studied the osteogenic potential of bone marrow on rabbits. Friedenstein demonstrated the existence of a nonhematopoietic stem cell within bone marrow more than a hundred years later. Since this discovery, the research on mesenchymal stem cell (MSC) has explored their therapeutic potential. The prevalent view during the second century was that mature cells were permanently locked into the differentiated state and could not return to a fully immature, pluripotent stem-cell state. Recently, Japanese scientist (first orthopaedist) Shinya Yamanaka proved that introduction of a small set of transcription factors into a differentiated cell was sufficient to revert the cell to a pluripotent state. Yamanaka shared the Nobel Prize in Physiology or Medicine and opened a new door for potential applications of MSCs. This manuscript describes the concept of MSCs from the period when it was relegated to the imagination to the beginning of the twenty-first century and their application in orthopaedic surgery. PMID:25750132

  13. Ranking economic history journals

    DEFF Research Database (Denmark)

    Di Vaio, Gianfranco; Weisdorf, Jacob Louis

    2010-01-01

    This study ranks-for the first time-12 international academic journals that have economic history as their main topic. The ranking is based on data collected for the year 2007. Journals are ranked using standard citation analysis where we adjust for age, size and self-citation of journals. We also...... compare the leading economic history journals with the leading journals in economics in order to measure the influence on economics of economic history, and vice versa. With a few exceptions, our results confirm the general idea about what economic history journals are the most influential for economic...... history, and that, although economic history is quite independent from economics as a whole, knowledge exchange between the two fields is indeed going on....

  14. Ranking Economic History Journals

    DEFF Research Database (Denmark)

    Di Vaio, Gianfranco; Weisdorf, Jacob Louis

    This study ranks - for the first time - 12 international academic journals that have economic history as their main topic. The ranking is based on data collected for the year 2007. Journals are ranked using standard citation analysis where we adjust for age, size and self-citation of journals. We...... also compare the leading economic history journals with the leading journals in economics in order to measure the influence on economics of economic history, and vice versa. With a few exceptions, our results confirm the general idea about what economic history journals are the most influential...... for economic history, and that, although economic history is quite independent from economics as a whole, knowledge exchange between the two fields is indeed going on....

  15. Marine Environmental History

    DEFF Research Database (Denmark)

    Poulsen, Bo

    2012-01-01

    This essay provides an overview of recent trends in the historiography of marine environmental history, a sub-field of environmental history which has grown tremendously in scope and size over the last c. 15 years. The object of marine environmental history is the changing relationship between...... human society and natural marine resources. Within this broad topic, several trends and objectives are discernable. The essay argue that the so-called material marine environmental history has its main focus on trying to reconstruct the presence, development and environmental impact of past fisheries...... and whaling operations. This ambition often entails a reconstruction also of how marine life has changed over time. The time frame rages from Paleolithicum to the present era. The field of marine environmental history also includes a more culturally oriented environmental history, which mainly has come...

  16. The rôle of the history and philosophy of technology in secondary education

    OpenAIRE

    Bissell, Christopher

    2013-01-01

    If the history and philosophy of science is seen as a useful approach in secondary education, then the history and philosophy of technology has an equal claim. The history of technology has often been seen as the poor relation of the history of science, yet its study can not only support the learning of scientific principles, but also engage students in a debate about contemporary and often contested technological issues – from the ‘information revolution’ to climate change. From this point ...

  17. Family history as a co-factor for adenocarcinoma and squamous cell carcinoma of the uterine cervix: results from two studies conducted in Costa Rica and the United States.

    Science.gov (United States)

    Zelmanowicz, Alice de M; Schiffman, Mark; Herrero, Rolando; Goldstein, Alisa M; Sherman, Mark E; Burk, Robert D; Gravitt, Patti; Viscidi, Ray; Schwartz, Peter; Barnes, Willard; Mortel, Rodrigue; Silverberg, Steven G; Buckland, Julie; Hildesheim, Allan

    2005-09-10

    Previous work suggests that cervical cancer may aggregate in families. We evaluated the association between a family history of gynecological tumors and risk of squamous cell and adenocarcinomas of the cervix in 2 studies conducted in Costa Rica and the United States. The Costa Rican study consisted of 2,073 women (85 diagnosed with CIN3 or cancer, 55 diagnosed with CIN2 and 1,933 controls) selected from a population-based study of 10,049 women. The U.S. study consisted of 570 women (124 with in situ or invasive adenocarcinomas, 139 with in situ or invasive squamous cell carcinomas of the cervix and 307 community-based controls) recruited as part of a multicentric case-control study in the eastern part of the United States. Information on family history of cervical and other cancers among first-degree relatives was ascertained via questionnaire. Information on other risk factors for cervical cancer was obtained via questionnaire. Human papillomavirus (HPV) exposure was assessed in both studies using broad spectrum HPV L1-based PCR testing of exfoliated cervicovaginal cells and in Costa Rica by additional testing of plasma collected from participants for antibodies against the L1 protein of HPV types 16, 18, 31 and 45 by ELISA. A family history of cervical cancer in a first-degree relative was associated with increased risk of squamous tumors in both studies (odds ration [OR] = 3.2 for CIN3/cancer vs. controls; 95% confidence interval [CI] = 1.1-9.4 in Costa Rica; OR = 2.6 for in situ/invasive squamous cell carcinoma cases vs. controls, 95% CI = 1.1-6.4 in the Eastern United States study). These associations were evident regardless of whether the affected relative was a mother, sister or daughter of the study participant. Furthermore, observed effects were not strongly modified by age. In Costa Rica, the effect persisted in analysis restricted to HPV-exposed individuals (OR = 3.0; 95% CI = 1.0-9.0), whereas in the Eastern United States study there was evidence of

  18. [History of Polish pharmacy].

    Science.gov (United States)

    Okuda, J; Okuda, R

    1993-01-01

    Doctoral thesis (in French) by Monika Debska-Donnet, entitled "History of pharmacy and pharmaceutical art collections in Poland" which was presented to Paris XI University (Faculty of Pharmaceutical and Biological Sciences) in 1991, was translated into Japanese and summarized. In this report, histories of pharmacy education, pharmacists, community pharmacies, pharmacopoeiae, pharmaceutical industries in Poland were described, and four representative Polish museums of history of pharmacy were also explained. PMID:11639718

  19. Feasible Histories, Maximum Entropy

    International Nuclear Information System (INIS)

    We consider the broadest possible consistency condition for a family of histories, which extends all previous proposals. A family that satisfies this condition is called feasible. On each feasible family of histories we choose a probability measure by maximizing entropy, while keeping the probabilities of commuting histories to their quantum mechanical values. This procedure is justified by the assumption that decoherence increases entropy. Finally, a criterion for identifying the nearly classical families is proposed

  20. Principles of Instructed Language Learning

    Science.gov (United States)

    Ellis, Rod

    2005-01-01

    This article represents an attempt to draw together findings from a range of second language acquisition studies in order to formulate a set of general principles for language pedagogy. These principles address such issues as the nature of second language (L2) competence (as formulaic and rule-based knowledge), the contributions of both focus on…

  1. Multimedia Principle in Teaching Lessons

    Science.gov (United States)

    Kari Jabbour, Khayrazad

    2012-01-01

    Multimedia learning principle occurs when we create mental representations from combining text and relevant graphics into lessons. This article discusses the learning advantages that result from adding multimedia learning principle into instructions; and how to select graphics that support learning. There is a balance that instructional designers…

  2. Ideario Educativo (Principles of Education).

    Science.gov (United States)

    Consejo Nacional Tecnico de la Educacion (Mexico).

    This document is an English-language abstract (approximately 1,500 words) which discusses an overall educational policy for Mexico based on Constitutional principles and those of humanism. The basic principles that should guide Mexican education as seen by the National Technical Council for Education are the following: (1) love of country; (2)…

  3. Principles and Criteria for Design

    DEFF Research Database (Denmark)

    Beghin, D.; Cervetto, D.; Hansen, Peter Friis

    1997-01-01

    The mandate of ISSC Committee IV.1 on principles and Criteria for Design is to report on the following:The ongoing concern for quantification of general economic and safety criteria for marine structures and for the development of appropriate principles for rational life cycle design using such...

  4. Principles of gene therapy

    OpenAIRE

    Mammen Biju; Ramakrishnan T; Sudhakar Uma; Vijayalakshmi

    2007-01-01

    Genes are specific sequences of bases that encode instructions to make proteins. When genes are altered so that encoded proteins are unable to carry out their normal functions, genetic disorders can result. Gene therapy is designed to introduce genetic material into cells to compensate for abnormal genes or to make a beneficial protein. This article reviews the fundamentals in gene therapy and its various modes of administration with an insight into the role of gene therapy in Periodontics an...

  5. Cooperative Station History Forms

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Various forms, photographs and correspondence documenting the history of Cooperative station instrumentation, location changes, inspections, and...

  6. BioCapacitor: A novel principle for biosensors.

    Science.gov (United States)

    Sode, Koji; Yamazaki, Tomohiko; Lee, Inyoung; Hanashi, Takuya; Tsugawa, Wakako

    2016-02-15

    Studies regarding biofuel cells utilizing biocatalysts such as enzymes and microorganisms as electrocatalysts have been vigorously conducted over the last two decades. Because of their environmental safety and sustainability, biofuel cells are expected to be used as clean power generators. Among several principles of biofuel cells, enzyme fuel cells have attracted significant attention for their use as alternative energy sources for future implantable devices, such as implantable insulin pumps and glucose sensors in artificial pancreas and pacemakers. However, the inherent issue of the biofuel cell principle is the low power of a single biofuel cell. The theoretical voltage of biofuel cells is limited by the redox potential of cofactors and/or mediators employed in the anode and cathode, which are inadequate for operating any devices used for biomedical application. These limitations inspired us to develop a novel biodevice based on an enzyme fuel cell that generates sufficient stable power to operate electric devices, designated "BioCapacitor." To increase voltage, the enzyme fuel cell is connected to a charge pump. To obtain a sufficient power and voltage to operate an electric device, a capacitor is used to store the potential generated by the charge pump. Using the combination of a charge pump and capacitor with an enzyme fuel cell, high voltages with sufficient temporary currents to operate an electric device were generated without changing the design and construction of the enzyme fuel cell. In this review, the BioCapacitor principle is described. The three different representative categories of biodevices employing the BioCapacitor principle are introduced. Further, the recent challenges in the developments of self-powered stand-alone biodevices employing enzyme fuel cells combined with charge pumps and capacitors are introduced. Finally, the future prospects of biodevices employing the BioCapacitor principle are addressed. PMID:26278505

  7. Principles of European Contract Law

    DEFF Research Database (Denmark)

    Lando, Ole; Beale, Hugh

    of articles, with a detailed commentary explaining the purpose and operation of each article and its relation to the remainder. Each article also has extensive comparative notes surveying the national laws and other international provisions on the topic. "The Principles of European Contract Law Parts......This text provides a comprehensive guide to the principles of European contract law. They have been drawn up by an independent body of experts from each Member State of the EU, under a project supported by the European Commission and many other organizations. The principles are stated in the form...... developing a common European legal culture. The European Parliament has twice called for the creation of a European Civil Code. The principles of European contract law are essential steps in these projects. This text provides a comprehensive guide to the Principles of European contract law. They have been...

  8. Journal of Mormon History Vol. 36, No. 4, Fall 2010

    OpenAIRE

    2010-01-01

    ARTICLES --Protecting the Family in the West: James Henry Martineau’s Response to Interfaith Marriage Dixie Dillon Lane, 1 --Hasty Baptisms in Japan: The Early 1980s in the LDS Church Jiro Numano, 18 --“Standing Where Your Heroes Stood”: Using Historical Tourism to Create American and Religious Identities Sarah Bill Schott, 41 --Community of Christ Principles of Church History: A Turning Point and a Good Example? Introduction Lavina Fielding Anderson, 67 --History in the Commun...

  9. A history of the histories of econometrics

    NARCIS (Netherlands)

    Boumans, Marcel; Dupont-Kieffer, Ariane

    2011-01-01

    Econometricians have from the start considered historical knowledge of their own discipline as reflexive knowledge useful for delineating their discipline, that is, for setting its disciplinary boundaries with respect to its aims, its methods, and its scientific values. As such, the histories writte

  10. Nuclear Energy Principles, Practices, and Prospects

    CERN Document Server

    Bodansky, David

    2008-01-01

    The world faces serious difficulties in obtaining the energy that will be needed in coming decades for a growing population, especially given the problem of climate change caused by fossil fuel use. This book presents a view of nuclear energy as an important carbon-free energy option. It discusses the nuclear fuel cycle, the types of reactors used today and proposed for the future, nuclear waste disposal, reactor accidents and reactor safety, nuclear weapon proliferation, and the cost of electric power. To provide background for these discussions, the book begins with chapters on the history of the development and use of nuclear energy, the health effects of ionizing radiation, and the basic physics principles of reactor operation. The text has been rewritten and substantially expanded for this edition, to reflect changes that have taken place in the eight years since the publication of the first edition and to provide greater coverage of key topics. These include the Yucca Mountain repository plans, designs ...

  11. An Inconvenient Principle

    Science.gov (United States)

    Bellac, Michel Le

    2014-11-01

    At the end of the XIXth century, physics was dominated by two main theories: classical (or Newtonian) mechanics and electromagnetism. To be entirely correct, we should add thermodynamics, which seemed to be grounded on different principles, but whose links with mechanics were progressively better understood thanks to the work of Maxwell and Boltzmann, among others. Classical mechanics, born with Galileo and Newton, claimed to explain the motion of lumps of matter under the action of forces. The paradigm for a lump of matter is a particle, or a corpuscle, which one can intuitively think of as a billiard ball of tiny dimensions, and which will be dubbed a micro-billiard ball in what follows. The second main component of XIXth century physics, electromagnetism, is a theory of the electric and magnetic fields and also of optics, thanks to the synthesis between electromagnetism and optics performed by Maxwell, who understood that light waves are nothing other than a particular case of electromagnetic waves. We had, on the one hand, a mechanical theory where matter exhibiting a discrete character (particles) was carried along well localized trajectories and, on the other hand, a wave theory describing continuous phenomena which did not involve transport of matter. The two theories addressed different domains, the only obvious link being the law giving the force on a charged particle submitted to an electromagnetic field, or Lorentz force. In 1905, Einstein put an end to this dichotomic wave/particle view and launched two revolutions of physics: special relativity and quantum physics. First, he showed that Newton's equations of motion must be modified when the particle velocities are not negligible with respect to that of light: this is the special relativity revolution, which introduces in mechanics a quantity characteristic of optics, the velocity of light. However, this is an aspect of the Einsteinian revolution which will not interest us directly, with the exception

  12. The Rigid Relation Principle, a New Weak Choice Principle

    CERN Document Server

    Hamkins, Joel David

    2011-01-01

    The rigid relation principle, introduced in this article, asserts that every set admits a rigid binary relation. This follows from the axiom of choice, because well-orders are rigid, but we prove that it is neither equivalent to the axiom of choice nor provable in Zermelo-Fraenkel set theory without the axiom of choice. Thus, it is a new weak choice principle. Nevertheless, the restriction of the principle to sets of reals (among other general instances) is provable without the axiom of choice.

  13. Principles of Security: Human, Cyber, and Biological

    CERN Document Server

    Stacey, Blake C

    2013-01-01

    Cybersecurity attacks are a major and increasing burden to economic and social systems globally. Here we analyze the principles of security in different domains and demonstrate an architectural flaw in current cybersecurity. Cybersecurity is inherently weak because it is missing the ability to defend the overall system instead of individual computers. The current architecture enables all nodes in the computer network to communicate transparently with one another, so security would require protecting every computer in the network from all possible attacks. In contrast, other systems depend on system-wide protections. In providing conventional security, police patrol neighborhoods and the military secures borders, rather than defending each individual household. Likewise, in biology, the immune system provides security against viruses and bacteria using primarily action at the skin, membranes, and blood, rather than requiring each cell to defend itself. We propose applying these same principles to address the c...

  14. A Survey of Physical Principles Attempting to Define Quantum Mechanics

    Science.gov (United States)

    Oas, Gary; Acacio de Barros, J.

    Quantum mechanics, one of the most successful theories in the history of science, was created to account for physical systems not describable by classical physics. Though it is consistent with all experiments conducted thus far, many of its core concepts (amplitudes, global phases, etc.) can not be directly accessed and its interpretation is still the subject of intense debate, more than 100 years since it was introduced. So, a fundamental question is why this particular mathematical model is the one that nature chooses, if indeed it is the correct model. In the past two decades there has been a renewed effort to determine what physical or informational principles define quantum mechanics. In this chapter, recent attempts at establishing reasonable physical principles are reviewed and their degree of success is tabulated. An alternative approach using joint quasi-probability distributions is shown to provide a common basis of representing most of the proposed principles. It is argued that having a common representation of the principles can provide intuition and guidance to relate current principles or advance new principles. The current state of affairs, along with some alternative views are discussed.

  15. Principles of Biomedical Engineering

    CERN Document Server

    Madihally, Sundararajan V

    2010-01-01

    Describing the role of engineering in medicine today, this comprehensive volume covers a wide range of the most important topics in this burgeoning field. Supported with over 145 illustrations, the book discusses bioelectrical systems, mechanical analysis of biological tissues and organs, biomaterial selection, compartmental modeling, and biomedical instrumentation. Moreover, you find a thorough treatment of the concept of using living cells in various therapeutics and diagnostics.Structured as a complete text for students with some engineering background, the book also makes a valuable refere

  16. Principles of gene therapy

    Directory of Open Access Journals (Sweden)

    Mammen Biju

    2007-01-01

    Full Text Available Genes are specific sequences of bases that encode instructions to make proteins. When genes are altered so that encoded proteins are unable to carry out their normal functions, genetic disorders can result. Gene therapy is designed to introduce genetic material into cells to compensate for abnormal genes or to make a beneficial protein. This article reviews the fundamentals in gene therapy and its various modes of administration with an insight into the role of gene therapy in Periodontics and future percepts and the technical and ethical issues of using gene therapy.

  17. History-Painting

    OpenAIRE

    Gagnon, Alex

    2014-01-01

    This was the first official "History-Painting" in The History-Project, a series of works of art - interdisciplinary! - that I engaged in from the Summer of 2001 until around circa 2005. It is an oil painting on Masonite board, roughly 6 inches by 8 inches.

  18. Musikterapiens historie i Danmark

    DEFF Research Database (Denmark)

    Bonde, Lars Ole

    2014-01-01

    Gennemgang af musikterapiens historie og udvikling i Danmark efter 2. verdenskrig. Revideret udgave af samme kapitel i "Musikterapi: Når ord ikke slår til" (2001).......Gennemgang af musikterapiens historie og udvikling i Danmark efter 2. verdenskrig. Revideret udgave af samme kapitel i "Musikterapi: Når ord ikke slår til" (2001)....

  19. Business history and risk

    OpenAIRE

    Gourvish , Terry

    2003-01-01

    CARR, in association with the Centre for Business History, University of Leeds, held a successful workshop on 'Business History and Risk' on 20 February 2002. The workshop, which was sponsored by the ESRC, brought together business historians, economists, accountants and risk analysts to develop an interdisciplinary discussion on understandings of risk by employers, workers and governments in different historical settings.

  20. History of Mathematics

    DEFF Research Database (Denmark)

    Hansen, Vagn Lundsgaard; Gray, Jeremy

    Volume 1 in Theme on "History of Mathematics", in "Encyclopedia of Life Support Systems (EOLSS), developed under the auspices of the UNESCO.......Volume 1 in Theme on "History of Mathematics", in "Encyclopedia of Life Support Systems (EOLSS), developed under the auspices of the UNESCO....

  1. On the Question of Validity of the Anthropic Principles

    OpenAIRE

    Hetesi, Zs.; Balázs, B.

    2006-01-01

    During the last centuries of human history, many questions was repeated in connection with the great problems of the existence and origin of human beings, and also of the Universe. The old questions of common sense and philosophy have not been solved in spite of the indisputable results of modern natural sciences. Recently the so-called anthropic principles show that these questions are still present. We investigated some important results of the modern cosmology and their consequences with r...

  2. Global versus Local -- Mach's Principle versus the Equivalence Principle

    CERN Document Server

    Singleton, Douglas

    2016-01-01

    The equivalence principle is the conceptual basis for general relativity. In contrast Mach's principle, although said to have been influential on Einstein in his formulation of general relativity, has not been shown to be central to the structure of general relativity. In this essay we suggest that the quantum effects of Hawking and Unruh radiation are a manifestation of a {\\it thermal} Mach's principle, where the local thermodynamic properties of the system are determined by the non-local structure of the quantum fields which determine the vacuum of a given spacetime. By comparing Hawking and Unruh temperatures for the same local acceleration we find a violation of the Einstein elevator version of the equivalence principle, which vanishes in the limit that the horizon is approached.

  3. Introductory remote sensing principles and concepts principles and concepts

    CERN Document Server

    Gibson, Paul

    2013-01-01

    Introduction to Remote Sensing Principles and Concepts provides a comprehensive student introduction to both the theory and application of remote sensing. This textbook* introduces the field of remote sensing and traces its historical development and evolution* presents detailed explanations of core remote sensing principles and concepts providing the theory required for a clear understanding of remotely sensed images.* describes important remote sensing platforms - including Landsat, SPOT and NOAA * examines and illustrates many of the applications of remotely sensed images in various fields.

  4. Critical reflections on the principle of beneficence in biomedicine

    Science.gov (United States)

    Munyaradzi, Mawere

    2012-01-01

    Medical ethics as a scholarly discipline and a system of moral principles that apply values and judgments to the practice of medicine encompasses its practical application in clinical settings as well as work on its history, philosophy, theology, anthropology and sociology. As such there are a number of values in medical ethics such as autonomy, non-maleficence, confidentiality, dignity, honesty, justice and beneficence, among others. These values act as guidelines for professionals in the medical fraternity and are therefore used to judge different cases in the fraternity. For purposes of this work, this paper examines the principle of beneficence in biomedicine. Using both hypothetical cases and others in real life situations, the paper reflects on the implications of beneficence in biomedicine. It argues that the principle of beneficence is a prima facie obligation that should “always be acted upon unless it conflicts on a particular occasion with an equal or stronger principle”. PMID:22514763

  5. Portraying User Interface History

    DEFF Research Database (Denmark)

    Jørgensen, Anker Helms

    The user interface is coming of age. Papers adressing UI history have appeared in fair amounts in the last 25 years. Most of them address particular aspects such as an in­novative interface paradigm or the contribution of a visionary or a research lab. Contrasting this, papers addres­sing UI...... history. Next the paper analyses a selected sample of papers on UI history at large. The analysis shows that the current state-of-art is featured by three aspects: Firstly internalism, in that the papers adress the tech­nologies in their own right with little con­text­ualization, secondly whiggism in that...... they largely address prevailing UI techno­logies, and thirdly history from above in that they focus on the great deeds of the visionaries. The paper then compares this state-of-art in UI history to the much more mature fields history of computing and history of technology. Based hereon, some...

  6. Voltammetry-Principles and Applications

    OpenAIRE

    Gulaboski, Rubin

    2008-01-01

    Voltammetry is a potentiodynamic technique that is inevitable tool in everyday experiments in many physicochemical and biological laboratories. The principles, potential applications and the advantages/disadvantages of various voltammetric techniques are described.

  7. Economy Principle in English Advertisements

    Institute of Scientific and Technical Information of China (English)

    Pan; Hong

    2015-01-01

    Languages evolve unceasingly according to the economy principle: to exchange the maximal amount of information through the minimal language codes expenditure.This paper analyzes economy in advertisements,especially the concise wording which saves layout,time and energy.

  8. Fundamental principles of particle detectors

    International Nuclear Information System (INIS)

    This paper goes through the fundamental physics of particles-matter interactions which is necessary for the detection of these particles with detectors. A listing of 41 concepts and detector principles are given. 14 refs., 11 figs

  9. Quantum mechanics principles and formalism

    CERN Document Server

    McWeeny, Roy

    2012-01-01

    Focusing on main principles of quantum mechanics and their immediate consequences, this graduate student-oriented volume develops the subject as a fundamental discipline, opening with review of origins of Schrödinger's equations and vector spaces.

  10. [History of tracheotomy].

    Science.gov (United States)

    Olszewski, Jurek; Miłoński, Jarosław

    2007-01-01

    The present notion - tracheotomy, originates from the Latin words trachea - windpipe, which comes from the combination of Latin "tracheia" and Greek "arteria" indicating an uneven road, and "tome" - cut. Procedures of pharyngotomy have a long-lasting history. First similar operations were found on the ancient Egyptian clay tablets dating back to 3600 BC. Mentions of pharyngotomy operations were found in the papyrus called Ebers's Papyrus dating back to about 1550 BC, which can obviously be treated as an encyclopaedia of the medical knowledge that the ancient Egyptians possessed. Guidelines for the person performing pharyngotomy were described in Rig Veda - the holy scriptures of Hindi medicine, about 2000 BC. Asclepiads of Prussia in Bithynia (124-156 BC), a Greek physician practising in Rome, is commonly considered the father of pharyngotomy. In the 1st century BC he documented an operation similar to pharyngotomy. Procedures similar to pharyngotomy were conducted by Claudius Galenus of Pergamon (about 130-200 AD) who was treating gladiators at the beginning of his medical career. A precise description of the technique in pharyngotomy performed by the method adopted from Antilla (3rd century AD) was presented by Paulos Aeginata (625-690 AD), whereas in modern times the first surgical pharyngotomy was performed by Antonio Brasavola (1490-1554) in 1546. In those times pharyngotomy operations were applied as life saving procedures and were associated with a desperate fight for life. The best example is given by Sanctorio Santorius (1561-1636) who pierced the trachea lumen with a trocar. All the experiences connected with the pharyngotomy technique were collected by Lorenz Heister (1683-1758) and published in his work "Surgery" in 1716. Until the end of 18th century the work finally established views about performing pharyngotomy operations. In 1856 Eugeniusz Bonchut conducted the first pharyngotomy in a child with passing an intubation tube into the trachea lumen

  11. The history of ZED-2

    International Nuclear Information System (INIS)

    This presentation gives the history of ZED-2 reactor at the Chalk River Laboratories. It traces the genealogy from Fermi Pile (1942) and ZEEP (1945) to the present ZED-2 reactor. ZED-2 is larger than ZEEP to allow larger critical lattices of larger CANDU type channels. There are two basic types of measurements made in ZED-2: critical size (buckling) of lattice and detailed reaction rate distribution in a cell. The presentation goes on to discuss research activities on ZED-2 from 1960 to the present.

  12. Does the relativity principle violate?

    International Nuclear Information System (INIS)

    Theoretical and experimental data about a possible existence in Nature of some preferred reference frame with a violation of the principle of relativity are considered. The Einstein's and Lorentz's points of view are compared. Although some experiments are known which, in opinion of their authors, indicate the relativity principle violation persuasive evidences supporting this conclusion are absent for the present. The proposals of new experiments in this region, particularly with electron spin precession, are discussed. 55 refs., 4 figs

  13. Teaching the Principles of Economics

    OpenAIRE

    N. Gregory Mankiw

    1998-01-01

    In this brief essay, I describe my approach to the principles course. I emphasize three themes. First, in teaching microeconomics, the tools of welfare economics should play a larger role than they have in the past. Second, in teaching macroeconomics, classical ideas should play a larger role than they have in the past. Third, in teaching all parts of the course, we instructors should be sure to stress the important principles and be careful not to overwhelm students with an excess of details.

  14. The Laughter as Hope Principle

    Directory of Open Access Journals (Sweden)

    Mateus Domingues da Silva

    2015-04-01

    Full Text Available The work aims to establish a parallel between the concept of laughter and the Hope Principle of Ernst Bloch, differentiating their relationship between the pursuit of individual happiness, said to be ideological, deceptive and precarious, and the pursuit of collective happiness, altruistic, that despite utopian it is also true and real, just for being selfless and real because, as a collective expression, indicating concretely and politically, is a real possibility.Keywords: Laughter, Hope Principle, Ernest Bloch, altruism.

  15. Toward a principle of quantumness

    CERN Document Server

    Stoica, Ovidiu-Cristinel

    2014-01-01

    Quantum correlations and other phenomena characteristic to a quantum world can be understood as simply consequences of a principle derived from the Born rule. This principle states that these specifically quantum phenomena are caused by the tension between initial conditions imposed by incompatible observations. This tension is found to be at the root of Bohr's complementarity, Heisenberg's uncertainty, results concerning non-locality, contextuality, quantum correlations in time and space.

  16. Economizing Principle in Accounting Research

    OpenAIRE

    Shyam Sunder

    2007-01-01

    Joel S. Demski's work is characterized by the austere discipline of applying the economizing principle to accounting and management phenomena. In natural sciences optimization is used as a structural principle for understanding the organization of the physical universe. As social scientists applied it to our self-conscious selves, economizing acquired a behavioral interpretation, leading to unnecessary and avoidable confusion with the findings of cognitive sciences. Important aspects of aggre...

  17. Notes on Cloud computing principles

    OpenAIRE

    Sandholm, Thomas; Lee, Dongman

    2015-01-01

    This letter provides a review of fundamental distributed systems and economic Cloud computing principles. These principles are frequently deployed in their respective fields, but their inter-dependencies are often neglected. Given that Cloud Computing first and foremost is a new business model, a new model to sell computational resources, the understanding of these concepts is facilitated by treating them in unison. Here, we review some of the most important concepts and how they relate to ea...

  18. Privacy principles, risks and harms

    OpenAIRE

    Wright, David; Raab, Charles

    2014-01-01

    The protection of privacy is predicated on the individual’s right to privacy and stipulates a number of principles that are primarily focused on information privacy or data protection and, as such, are insufficient to apply to other types of privacy and to the protection of other entities beyond the individual. This article identifies additional privacy principles that would apply to other types of privacy and would enhance the consideration of risks or harms to the individual, to groups and ...

  19. Principles for Reliable Operating Systems

    OpenAIRE

    Denning, Peter J.

    2002-01-01

    Peter J. Denning reminisces about joint work in 1975 with Roger Needham on design principles for reliable operating systems. He recounts vivid memories of two findings, about interrupts and about capability addressing. These principles are still valid a quarter century later and remain in wide use. Back in the summer of 1975, Dorothy Denning and I, then still newlyweds, spent a month at Cambridge. During that time Roger Needham and I met daily to discuss topics in the design of opera...

  20. Principles-Driven Forensic Analysis

    OpenAIRE

    Peisert, Sean; Bishop, Matt; Karin, Sidney; Marzullo, Keith

    2005-01-01

    It is possible to enhance our understanding of what has happened on a computer system by using forensic techniques that do not require prediction of the nature of the attack, the skill of the attacker, or the details of the system resources or objects affected. These techniques address five fundamental principles of computer forensics. These principles include recording data about the entire operating system, particularly user space events and environments, and interpreting events at differen...

  1. Corporate Governance: Principles and Regulations

    OpenAIRE

    PĂCALĂ Anca

    2012-01-01

    Corporate governance is only part of the broader economic context in which firms operate and includes, for example, macroeconomic policies,competition, or the markets of production factors. Contemporary debate on corporate governance refers in particular to the principles mentioned in three papers published after 1990: the UK Cadbury Report(1992), OECD Principles of Corporate Governance (1998 and 2004), and the Sarbanes-Oxley Law in the U.S. (2002). Cadbury and the OECD reports present genera...

  2. A history of mathematics

    CERN Document Server

    Boyer, Carl B

    2011-01-01

    The updated new edition of the classic and comprehensive guide to the history of mathematics. For more than forty years, A History of Mathematics has been the reference of choice for those looking to learn about the fascinating history of humankind's relationship with numbers, shapes, and patterns. This revised edition features up-to-date coverage of topics such as Fermat's Last Theorem and the Poincaré Conjecture , in addition to recent advances in areas such as finite group theory and computer-aided proofs.: Distills thousands of years of mathematics into a single, approachable volume; Cover

  3. Science A history

    CERN Document Server

    Gribbin, John

    2002-01-01

    From award-winning science writer John Gribbin, "Science: A History" is the enthralling story of the men and women who changed the way we see the world, and the turbulent times they lived in. From Galileo, tried by the Inquisition for his ideas, to Newton, who wrote his rivals out of the history books; from Marie Curie, forced to work apart from male students for fear she might excite them, to Louis Agassiz, who marched his colleagues up a mountain to prove that the ice ages had occurred. Filled with pioneers, visionaries, eccentrics and madmen, this is the history of science as it has never been told before.

  4. Arrangement of radial actin bundles in the growth cone of Aplysia bag cell neurons shows the immediate past history of filopodial behavior

    OpenAIRE

    Katoh, Kaoru; Hammar, Katherine; Peter J S Smith; Oldenbourg, Rudolf

    1999-01-01

    Filopodia that protrude forward from the lamellipodium, located at the leading edge of a neuronal growth cone, are needed to guide the extension of a nerve cell. At the core of each filopodium an actin bundle forms and grows into the lamellipodium. By using kymographs of time-lapse polarized light images we examined the relationship between the behavior of the filopodia, the actin bundles immediately proximal to the filopodia, and the shapes and composition of actin bundles in the whole lamel...

  5. Sources of History for "A Psychology of Verbal Communication"

    Science.gov (United States)

    O'Connell, Daniel C.; Kowal, Sabine

    2011-01-01

    There is a standard version of the history of modern mainstream psycholinguistics that emphasizes an extraordinary explosion of research in mid twentieth century under the guidance and leadership of George A. Miller and Noam Chomsky. The narrative is cast as a dramatic shift away from behavioristic principles and toward mentalistic principles…

  6. Nanotechnology: Principles and Applications

    Science.gov (United States)

    Logothetidis, S.

    Nanotechnology is one of the leading scientific fields today since it combines knowledge from the fields of Physics, Chemistry, Biology, Medicine, Informatics, and Engineering. It is an emerging technological field with great potential to lead in great breakthroughs that can be applied in real life. Novel nano- and biomaterials, and nanodevices are fabricated and controlled by nanotechnology tools and techniques, which investigate and tune the properties, responses, and functions of living and non-living matter, at sizes below 100 nm. The application and use of nanomaterials in electronic and mechanical devices, in optical and magnetic components, quantum computing, tissue engineering, and other biotechnologies, with smallest features, widths well below 100 nm, are the economically most important parts of the nanotechnology nowadays and presumably in the near future. The number of nanoproducts is rapidly growing since more and more nanoengineered materials are reaching the global market The continuous revolution in nanotechnology will result in the fabrication of nanomaterials with properties and functionalities which are going to have positive changes in the lives of our citizens, be it in health, environment, electronics or any other field. In the energy generation challenge where the conventional fuel resources cannot remain the dominant energy source, taking into account the increasing consumption demand and the CO2 emissions alternative renewable energy sources based on new technologies have to be promoted. Innovative solar cell technologies that utilize nanostructured materials and composite systems such as organic photovoltaics offer great technological potential due to their attractive properties such as the potential of large-scale and low-cost roll-to-roll manufacturing processes The advances in nanomaterials necessitate parallel progress of the nanometrology tools and techniques to characterize and manipulate nanostructures. Revolutionary new approaches

  7. Cosmic Reionization Study : Principle Component Analysis After Planck

    CERN Document Server

    Liu, Yang; Li, Si-Yu; Li, Yong-Ping; Zhang, Xinmin

    2015-01-01

    The study of reionization history plays an important role in understanding the evolution of our universe. It is commonly believed that the intergalactic medium (IGM) in our universe are fully ionized today, however the reionizing process remains to be mysterious. A simple instantaneous reionization process is usually adopted in modern cosmology without direct observational evidence. However, the history of ionization fraction, $x_e(z)$ will influence cosmic microwave background (CMB) observables and constraints on optical depth $\\tau$. With the mocked future data sets based on featured reionization model, we find the bias on $\\tau$ introduced by instantaneous model can not be neglected. In this paper, we study the cosmic reionization history in a model independent way, the so called principle component analysis (PCA) method, and reconstruct $x_e (z)$ at different redshift $z$ with the data sets of Planck, WMAP 9 years temperature and polarization power spectra, combining with the baryon acoustic oscillation (...

  8. Oral history database

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Separately, each history provides an in depth view into the professional and personal lives of individual participants. Together, they have the power to illuminate...

  9. IUTAM a short history

    CERN Document Server

    Juhasz, Stephen

    2016-01-01

    This book presents extensive information related to the history of IUTAM. The initial chapters focus on IUTAM’s history and selected organizational aspects. Subsequent chapters provide extensive data and statistics, while the closing section showcases photos from all periods of the Union’s history. The history of IUTAM, the International Union on Theoretical and Applied Mechanics, began at a conference in 1922 in Innsbruck, Austria, where von Kármán put forward the idea of an international congress including the whole domain of applied mechanics. In 1946 IUTAM was then formally launched in Paris/France. IUTAM has since time organized more than 24 world congresses and 380 symposia, representing all fields of mechanics and highlighting advances by prominent international researchers. The efforts of IUTAM and its about 50 member countries serve to promote the mechanical sciences and the advancement of human society, addressing many key challenges. In this context, IUTAM preserves important traditions while...

  10. History Begins at Home

    Science.gov (United States)

    McCully, George E.

    1978-01-01

    Suggests that high school history can be more interesting and useful if students are taught to formulate, evaluate, and use historical statements on the basis of evidence available in primary sources. Outlines a curriculum based on this thesis. (AV)

  11. History of Lake Andes

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — Information about the history and management of Lake Andes is compiled in this report. It is intended to help future refuge managers become acquainted with the...

  12. History of Bioterrorism: Botulism

    Medline Plus

    Full Text Available ... for Emergency Health Professionals Clinician Outreach (COCA) Crisis & Risk Communication (CERC) Laboratory Information Health Alert Network (HAN) ... Cleaning Public Health Emergency Response Guide Reaching At-Risk Populations MedCon Video: "The History of Bioterrorism" Recommend ...

  13. Water Level Station History

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Images contain station history information for 175 stations in the National Water Level Observation Network (NWLON). The NWLON is a network of long-term,...

  14. History of Bioterrorism: Botulism

    Medline Plus

    Full Text Available ... as bioterrorist weapons. Watch the Complete Program "The History of Bioterroism" (26 min 38 sec) Watch ... Public Health Response," co-produced by the United States Army Medical Research Institute of Infectious Diseases (USAMRIID), the Food ...

  15. History of Catalan numbers

    OpenAIRE

    Pak, Igor

    2014-01-01

    We give a brief history of Catalan numbers, from their first discovery in the 18th century to modern times. This note will appear as an appendix in Richard Stanley's forthcoming book on Catalan numbers.

  16. GBM Accreting Pulsar Histories

    Data.gov (United States)

    National Aeronautics and Space Administration — For each source we plot the history of pulse frequency and pulsed flux measured using the Fermi Gamma-Ray Burst Monitor (GBM) NaI detectors. For these measurements...

  17. History of Bioterrorism: Botulism

    Medline Plus

    Full Text Available ... Emergency Response Guide Reaching At-Risk Populations MedCon Video: "The History of Bioterrorism" Recommend on Facebook Tweet Share Compartir This video describes the Category A diseases: smallpox, anthrax, botulism, ...

  18. Knowledge management and history

    OpenAIRE

    Ermine, Jean-Louis; pauget, bertrand; Beretti, Annie; Tortorici, Gilbert

    2004-01-01

    International audience Capitalisation of the history of a technology, a technique or a concept within an industrial company is relevant to historians. However it largely exceeds the historical problems from a Knowledge Management point of view. In this context, it can be the subject of specific approaches especially Knowledge Engineering. However, it faces two types of difficulties: - The techniques in History have few modelling tools, and are even rather reticent with the use of such tool...

  19. Teaching History through English

    OpenAIRE

    Lasnik, Andreja

    2014-01-01

    This diploma thesis discusses Content and Language Integrated Learning (CLIL) as a new and innovative educational approach in different countries with the emphasis on the current status of CLIL in Slovenia. However, the main focus of the diploma thesis is to discuss the extent of using English in History lessons and out-of-school activities related to history topics among Year 8 and Year 9 primary school learners. Although CLIL has been part of the national curricula in several countries in E...

  20. Economics, History, and Causation

    OpenAIRE

    Randall Morck; Bernard Yeung

    2011-01-01

    Economics and history both strive to understand causation: economics using instrumental variables econometrics and history by weighing the plausibility of alternative narratives. Instrumental variables can lose value with repeated use because of an econometric tragedy of the commons bias: each successful use of an instrument potentially creates an additional latent variable bias problem for all other uses of that instrument - past and future. Economists should therefore consider historians' a...

  1. Transformation of History textbooks

    DEFF Research Database (Denmark)

    Haue, Harry

    2013-01-01

    Artiklen omhandler danske og tyske lærebøger i historie over de seneste to århundreder med hensyn til deres vægtning af det nationale og det globale stof.......Artiklen omhandler danske og tyske lærebøger i historie over de seneste to århundreder med hensyn til deres vægtning af det nationale og det globale stof....

  2. Market principles toward the land plots assessment

    OpenAIRE

    A. Koshel

    2015-01-01

    Market principles toward the agricultural land plots assessment and the features are analyzed. The detailed study of economic valuation principles of agricultural land is conducted. Application of the principles of such evaluation in the process of mass valuation is suggested

  3. Geoethics: history and further development

    Science.gov (United States)

    Nemec, Vaclav

    2013-04-01

    Problems of ethics and morality can be retrospectively followed in the history of human kind to its earliest phases. The new scientific discipline of GEOETHICS since 1991 has brought to the attention various topics of Earth sciences needed to be discussed from new specific ethical points of view (e.g. prudent consumption of mineral resources). The present frequency of natural disasters all over the world gives serious signals for intensifying an appropriate geoethical discussion. Significant events in the development of geoethics during the last 20 years include: international meetings organized since 1992 usually in 2 years terms as part of the Mining Pribram Symposia (Czech Republic), regular forums at all International Geological Congresses since 1996 (individual papers already in 1992) and formation of the Working Group on Geoethics in 2004 under the umbrella of the Association of Geoscientists for International Development (AGID) as well as establishing AGID National Chapters in several states (e.g. in Spain web pages http://tierra.rediris.es/Geoethics_Planetary_Protection/ with all GEOETHICS NEWS issued since 2007). - Geoethical principles and geological factors are to be considered in any scenario of a "sustainable development". At any responsible level of state authorities and self-governments as well as in any context of international co-operation, geoethics might be able to help in paving a better way for the needed understanding of nature by human kind. Geoethical principles (the planet Earth = absolute value of the life; principles of respect, interdependence, harmony and balance of interests, responsibility to future generations, prognosticating, precaution, reversibility, integration, frugality etc.) should be incorporated in the optimal way into the consciousness and life of the contemporaneous global society. In October 2011 at Pribram the future main trends were agreed in the INTERNATIONAL DECLARATION ON GEOETHICS: 1) significance of geoethics in

  4. The early history of the earth

    Directory of Open Access Journals (Sweden)

    C. P. Snyman

    1988-03-01

    Full Text Available In view of the principle of actualism the early history of the earth must be explained on the basis of present-day natural phenomena and the basic Laws of Nature. The study of the solar system leads to the conclusion that the planets were formed as by-products when the sun developed from a rotating cloud of cosmic gas and dust. The protoplanets or planetesimals could have accreted as a result of mutual collisions, during which they could have become partly molten so that they could differentiate into a crust, a mantle and a core on the basis of differences in density.

  5. Cancer: a de-repression of a default survival program common to all cells?: a life-history perspective on the nature of cancer.

    Science.gov (United States)

    Vincent, Mark

    2012-01-01

    Cancer viewed as a programmed, evolutionarily conserved life-form, rather than just a random series of disease-causing mutations, answers the rarely asked question of what the cancer cell is for, provides meaning for its otherwise mysterious suite of attributes, and encourages a different type of thinking about treatment. The broad but consistent spectrum of traits, well-recognized in all aggressive cancers, group naturally into three categories: taxonomy ("phylogenation"), atavism ("re-primitivization") and robustness ("adaptive resilience"). The parsimonious explanation is not convergent evolution, but the release of an highly conserved survival program, honed by the exigencies of the Pre-Cambrian, to which the cancer cell seems better adapted; and which is recreated within, and at great cost to, its host. Central to this program is the Warburg Effect, whose malign influence permeates well beyond aerobic glycolysis to include biomass interconversion and genomic heuristics. Warburg-type metabolism and genomic instability are targets whose therapeutic disablement is a major priority. PMID:22105565

  6. An idiosyncratic history of burn scars.

    Science.gov (United States)

    Petro, Jane A

    2015-03-01

    The history of burn scars can best be found in military medical history. The care of wounded soldiers documented in the Illiad reflected the trauma of the weapons of war, arrow, spear, sword, and ax. The introduction of gunpowder in the 14th century, increasingly sophisticated explosives, and in modern times, petroleum-driven vehicles, including airplanes, created a new subset of wounds requiring attention and post-survival scars challenging the quality of survival. This article selects from among a myriad of examples of modern military treatments as they relate to those survivors. Larrey, with Napolean's Grand Army, Sir Harold Gilles during and following World War I, and the Boston area preparation and response to the Cocoanut Grove Fire in 1942 are the principle topics examined. Recent modern interventions, related to the survival of horrific blast and burn injuries, with modern wound care and scar manipulation techniques provide context to the current ability to modify healing and scars. PMID:25922950

  7. The thermodynamics of quantum spacetime histories

    CERN Document Server

    Smolin, Lee

    2015-01-01

    We show that the simplicity constraints, which define the dynamics of spin foam models, imply, and are implied by, the first law of thermodynamics, when the latter is applied to causal diamonds in the quantum spacetime. This result reveals an intimate connection between the holographic nature of gravity, as reflected by the Bekenstein entropy, and the fact that general relativity and other gravitational theories can be understood as constrained topological field theories. To state and derive this correspondence we describe causal diamonds in the causal structure of spin foam histories and generalize arguments given for the near horizon region of black holes by Frodden, Gosh and Perez and Bianchi. This allows us to apply a recent argument of Jacobson to show that if a spin foam history has a semiclassical limit described in terms of a smooth metric geometry, that geometry satisfies the Einstein equations. These results suggest also a proposal for a quantum equivalence principle.

  8. RELATIVE PRINCIPLE COMPONENT AND RELATIVE PRINCIPLE COMPONENT ANALYSIS ALGORITHM

    Institute of Scientific and Technical Information of China (English)

    Wen Chenglin; Wang Tianzhen; Hu Jing

    2007-01-01

    In this letter, the new concept of Relative Principle Component (RPC) and method of RPC Analysis (RPCA) are put forward. Meanwhile, the concepts such as Relative Transform (RT), Rotundity Scatter (RS) and so on are introduced. This new method can overcome some disadvantages of the classical Principle Component Analysis (PCA) when data are rotundity scatter. The RPC selected by RPCA are more representative, and their significance of geometry is more notable, so that the application of the new algorithm will be very extensive. The performance and effectiveness are simply demonstrated by the geometrical interpretation proposed.

  9. Other Histories: Photography and Australia’

    OpenAIRE

    Helen Ennis

    2011-01-01

    This paper deals with Australian photographys historiography in published survey histories. It argues that photography has a doubled history, represented in broader histories of Australian art and its own medium specific histories. It considers photographys treatment in recent histories of Australian art by Christopher Allen (1997), Andrew Sayers (2001) and John McDonald (2008). The four survey histories of photography published to date – by Jack Cato (1955), Gael Newton (1988), Anne Marie-Wi...

  10. IGBT scaling principle toward CMOS compatible wafer processes

    Science.gov (United States)

    Tanaka, Masahiro; Omura, Ichiro

    2013-02-01

    A scaling principle for trench gate IGBT is proposed. CMOS technology on large diameter wafer enables to produce various digital circuits with higher performance and lower cost. The transistor cell structure becomes laterally smaller and smaller and vertically shallower and shallower. In contrast, latest IGBTs have rather deeper trench structure to obtain lower on-state voltage drop and turn-off loss. In the aspect of the process uniformity and wafer warpage, manufacturing such structure in the CMOS factory is difficult. In this paper, we show the scaling principle toward shallower structure and better performance. The principle is theoretically explained by our previously proposed "Structure Oriented" analytical model. The principle represents a possibility of technology direction and roadmap for future IGBT for improving the device performance consistent with lower cost and high volume productivity with CMOS compatible large diameter wafer technologies.

  11. Nanowire field effect transistors principles and applications

    CERN Document Server

    Jeong, Yoon-Ha

    2014-01-01

    “Nanowire Field Effect Transistor: Basic Principles and Applications” places an emphasis on the application aspects of nanowire field effect transistors (NWFET). Device physics and electronics are discussed in a compact manner, together with the p-n junction diode and MOSFET, the former as an essential element in NWFET and the latter as a general background of the FET. During this discussion, the photo-diode, solar cell, LED, LD, DRAM, flash EEPROM and sensors are highlighted to pave the way for similar applications of NWFET. Modeling is discussed in close analogy and comparison with MOSFETs. Contributors focus on processing, electrostatic discharge (ESD) and application of NWFET. This includes coverage of solar and memory cells, biological and chemical sensors, displays and atomic scale light emitting diodes. Appropriate for scientists and engineers interested in acquiring a working knowledge of NWFET as well as graduate students specializing in this subject.

  12. Design principles of shift current photovoltaics

    Science.gov (United States)

    Cook, Ashley; Fregoso, Benjamin; de Juan, Fernando; Moore, Joel

    While the basic principles and limitations of conventional solar cells are well understood, relatively little attention has gone toward evaluating and maximizing the potential efficiency of photovoltaic devices based on shift currents. In this work, a sum rule approach is introduced and used to outline design principles for optimizing shift currents for photon energies near the band gap, which depend on wavefunctions via Berry connections as well as standard band structure. Using these we identify two new classes of shift current photovoltaics, ferroelectric polymer films and orthorhombic monochalcogenides, both of which exhibit peak photoresponsivities larger than predictions for previously-known photovoltaics of this type. Using physically-motivated tight-binding models, the full frequency dependent response of these materials is obtained. Exploring the phase space of these models, we find photoresponsivities that can exceed 100 mA/W. These results show that considering the microscopic origin of shift current via effective models allows one to improve the possible efficiency of devices using this mechanism and better grasp their potential to compete with conventional solar cells. This work was completed with the support of an NSERC Michael Smith Foreign Study Supplement.

  13. Teaching Environmental History: Environmental Thinking and Practice in Europe, 1500 to the Present

    Science.gov (United States)

    Schwartz, Robert M.

    2006-01-01

    In this article, the author describes the teaching methods he used in an environmental history course. He relates that the ecologist's web of life serves as his guiding principle for teaching in his course. From an imagined center of the web, he relates that he and his class move outward to explore two main areas of environmental history in the…

  14. Cosmological implications of Heisenberg's principle

    CERN Document Server

    Gonzalo, Julio A

    2015-01-01

    The aim of this book is to analyze the all important implications of Heisenberg's Uncertainty Principle for a finite universe with very large mass-energy content such as ours. The earlier and main contributors to the formulation of Quantum Mechanics are briefly reviewed regarding the formulation of Heisenberg's Principle. After discussing “indeterminacy” versus ”uncertainty”, the universal constants of physics are reviewed and Planck's units are given. Next, a novel set of units, Heisenberg–Lemaitre units, are defined in terms of the large finite mass of the universe. With the help of Heisenberg's principle, the time evolution of the finite zero-point energy for the universe is investigated quantitatively. Next, taking advantage of the rigorous solutions of Einstein's cosmological equation for a flat, open and mixed universe of finite mass, the most recent and accurate data on the “age” (to) and the expansion rate (Ho) of the universe and their implications are reconsidered.

  15. The 4th Thermodynamic Principle?

    International Nuclear Information System (INIS)

    It should be emphasized that the 4th Principle above formulated is a thermodynamic principle and, at the same time, is mechanical-quantum and relativist, as it should inevitably be and its absence has been one of main the theoretical limitations of the physical theory until today.We show that the theoretical discovery of Dimensional Primitive Octet of Matter, the 4th Thermodynamic Principle, the Quantum Hexet of Matter, the Global Hexagonal Subsystem of Fundamental Constants of Energy and the Measurement or Connected Global Scale or Universal Existential Interval of the Matter is that it is possible to be arrived at a global formulation of the four 'forces' or fundamental interactions of nature. The Einstein's golden dream is possible

  16. Quantum measurements and Landauer's principle

    Science.gov (United States)

    Shevchenko, V.

    2015-05-01

    Information processing systems must obey laws of physics. One of particular examples of this general statement is known as Landauer's principle - irreversible operations (such as erasure) performed by any computing device at finite temperature have to dissipate some amount of heat bound from below. Together with other results of this kind, Landauer's principle represents a fundamental limit any modern or future computer must obey. We discuss interpretation of the physics behind the Landauer's principle using a model of Unruh-DeWitt detector. Of particular interest is the validity of this limit in quantum domain. We systematically study finite time effects. It is shown, in particular, that in high temperature limit finiteness of measurement time leads to renormalization of the detector's temperature.

  17. Variational Principle for Planetary Interiors

    CERN Document Server

    Zeng, Li

    2016-01-01

    In the past few years, the number of confirmed planets has grown above 2000. It is clear that they represent a diversity of structures not seen in our own solar system. In addition to very detailed interior modeling, it is valuable to have a simple analytical framework for describing planetary structures. Variational principle is a fundamental principle in physics, entailing that a physical system follows the trajectory which minimizes its action. It is alternative to the differential equation formulation of a physical system. Applying this principle to planetary interior can beautifully summarize the set of differential equations into one, which provides us some insight into the problem. From it, a universal mass-radius relation, an estimate of error propagation from equation of state to mass-radius relation, and a form of virial theorem applicable to planetary interiors are derived.

  18. Principles of neural information processing

    CERN Document Server

    Seelen, Werner v

    2016-01-01

    In this fundamental book the authors devise a framework that describes the working of the brain as a whole. It presents a comprehensive introduction to the principles of Neural Information Processing as well as recent and authoritative research. The books´ guiding principles are the main purpose of neural activity, namely, to organize behavior to ensure survival, as well as the understanding of the evolutionary genesis of the brain. Among the developed principles and strategies belong self-organization of neural systems, flexibility, the active interpretation of the world by means of construction and prediction as well as their embedding into the world, all of which form the framework of the presented description. Since, in brains, their partial self-organization, the lifelong adaptation and their use of various methods of processing incoming information are all interconnected, the authors have chosen not only neurobiology and evolution theory as a basis for the elaboration of such a framework, but also syst...

  19. Quantum completeness and consistent histories

    International Nuclear Information System (INIS)

    The different versions of the Kochen-Specker Theorem show that quantum mechanics (QM) cannot be supplemented by hidden variables given two plausible constraints. This collection of results is generally interpreted as showing that QM is complete in the following way. Consider that a QM system's state allows calculating probabilities for the possession of values of observables. Then the system has only those values for which the state delivers probability 1. For a positive probability different from 1 the system is then thought to adopt a value as a result of the measurement interaction. But this interpretation is fundamentally problematic. In particular, it can be easily brought into contradiction with QM itself, given two very general principles concerning probabilities in a physical theory. This difficulty which may be called the completeness problem is seldom noticed. A notable exception is the consistent histories interpretation (CHI) of QM. The CHI points out the problem and proposes a solution. Here I investigate the proposal. I argue that the CHI can avoid contradiction only at the cost of distorting the original sense of the completeness assumption and prohibiting the hidden-variables question itself. Hence, its attempt to overcome the problem is implausible.

  20. AAS Oral History Project

    Science.gov (United States)

    Buxner, Sanlyn; Holbrook, Jarita; AAS Oral History Team

    2016-06-01

    Now in its fourth year, the AAS Oral History Project has interviewed over 80 astronomers from all over the world. Led by the AAS Historical Astronomy Division (HAD) and partially funded by the American Institute of Physics Niels Bohr Library and ongoing support from the AAS, volunteers have collected oral histories from astronomers at professional meetings starting in 2015, including AAS, DPS, and the IAU general assembly. Each interview lasts one and a half to two hours and focuses on interviewees’ personal and professional lives. Questions include those about one’s family, childhood, strong influences on one’s scientific career, career path, successes and challenges, perspectives on how astronomy is changing as a field, and advice to the next generation. Each interview is audio recorded and transcribed, the content of which is checked with each interviewee. Once complete, interview transcripts are posted online as part of a larger oral history library at https://www.aip.org/history-programs/niels-bohr-library/oral-histories. Future analysis will reveal a rich story of astronomers and will help the community address issues of diversity, controversies, and the changing landscape of science. We are still recruiting individuals to be interviewed from all stages of career from undergraduate students to retired and emeritus astronomers. Contact Jarita Holbrook to schedule an interview or to find out more information about the project (astroholbrook@gmail.com). Also, contact Jarita Holbrook if you would like to become an interviewer for the project.

  1. Principles and applications of tribology

    CERN Document Server

    Moore, Desmond F

    1975-01-01

    Principles and Applications of Tribology provides a mechanical engineering perspective of the fundamental understanding and applications of tribology. This book is organized into two parts encompassing 16 chapters that cover the principles of friction and different types of lubrication. Chapter 1 deals with the immense scope of tribology and the range of applications in the existing technology, and Chapter 2 is devoted entirely to the evaluation and measurement of surface texture. Chapters 3 to 5 present the fundamental concepts underlying the friction of metals, elastomers, and other material

  2. Pauli principle and parton distributions

    Energy Technology Data Exchange (ETDEWEB)

    Buccella, F. [Universita di Napoli - Federico 2 (Italy)

    1995-11-01

    Different facts conspire to show the role of the Pauli principle for parton distributions. Fermi-Dirac functions, where the broader shape in x for higher first moment correlation dictated by Pauli principle is evident, give rise to a fair description of deep inelastic processes. The interpretation of the defect in the Gottfried sum rule as a consequence of Pauli blocking in the proton against the parton u{up_arrow}, the one dominating at high x and with the first moment higher than for the other quarks, leads to corresponding defects for the spin sum rules consistent with the present experimental knowledge. (orig.)

  3. Pauli principle and parton distributions

    International Nuclear Information System (INIS)

    Different facts conspire to show the role of the Pauli principle for parton distributions. Fermi-Dirac functions, where the broader shape in x for higher first moment correlation dictated by Pauli principle is evident, give rise to a fair description of deep inelastic processes. The interpretation of the defect in the Gottfried sum rule as a consequence of Pauli blocking in the proton against the parton u↑, the one dominating at high x and with the first moment higher than for the other quarks, leads to corresponding defects for the spin sum rules consistent with the present experimental knowledge. (orig.)

  4. Microhydrodynamics principles and selected applications

    CERN Document Server

    Kim, Sangtae

    2005-01-01

    ""This book is well organized and comprehensive . . . an eloquent and enduring statement of significant hydrodynamic principles."" - AIChE JournalMicrohydrodynamics concerns the flow and related phenomena pertinent to the motion of small particles suspended in viscous fluids. This text focuses on determining the motion of a particle or particles through a viscous fluid in bounded and unbounded flow. Its central theme is the mobility relation between particle motion and forces.Microhydrodynamics: Principles and Selected Applications functions as a manual that explains methods for solving partic

  5. Teaching Spreadsheets: Curriculum Design Principles

    CERN Document Server

    Tort, Francoise

    2010-01-01

    EuSpRIG concerns direct researchers to revisit spreadsheet education, taking into account error auditing tools, checklists, and good practices. This paper aims at elaborating principles to design a spreadsheet curriculum. It mainly focuses on two important issues. Firstly, it is necessary to establish the spreadsheet invariants to be taught, especially those concerning errors and good practices. Secondly, it is important to take into account the learners' ICT experience, and to encourage them to attitudes that foster self-learning. We suggest key principles for spreadsheet teaching, and we illustrate them with teaching guidelines.

  6. Cooling towers principles and practice

    CERN Document Server

    Hill, G B; Osborn, Peter D

    2013-01-01

    Cooling Towers: Principles and Practice, Third Edition, aims to provide the reader with a better understanding of the theory and practice, so that installations are correctly designed and operated. As with all branches of engineering, new technology calls for a level of technical knowledge which becomes progressively higher; this new edition seeks to ensure that the principles and practice of cooling towers are set against a background of up-to-date technology. The book is organized into three sections. Section A on cooling tower practice covers topics such as the design and operation of c

  7. A Critical Dance Studies Examination of the Teaching Methodologies, Exercises, and Principles of Pilates

    OpenAIRE

    Holmes, Sarah

    2013-01-01

    This project examines the teaching methodologies, exercises, and Principles of the exercise practice commonly known as Pilates from a Critical Dance Studies perspective. Muscle memory, or embodied knowledge, is significant to dance scholarship in that embodied knowledge houses important unwritten cultural, social, and political histories. This project examines the racial, gendered, and class-based issues embedded in the exercises and Principles of Pilates, revealing the ways that the embodied...

  8. Methodological principles outline discipline "Organization studies-tourism activity" using information technologies.

    Directory of Open Access Journals (Sweden)

    Kozina Zh.L.

    2011-08-01

    Full Text Available The basic methodological principles of the disciplines of tourism and local history with information technology. 15 analyzed the literature and experience of leading experts in the field of sports and health tourism, and orienteering. Identified principles of academic disciplines of tourism and local history: the shift in emphasis from sports tourism to the cognitive, health tourism, the development of spiritual qualities, acquisition of life skills in nature, discovery and development of pedagogical and psychological abilities, character traits through the study of native land, the development of cognitive-research abilities, physical abilities, motor skills, application of modern information technology.

  9. Radiation protection principles of NCRP.

    Science.gov (United States)

    Kase, Kenneth R

    2004-09-01

    The current recommendations of the National Council on Radiation Protection and Measurements (NCRP) relative to ionizing radiation are based on radiation protection principles that developed historically as information about radiation effects on human populations became available. Because the NCRP Charter states that the NCRP will cooperate with the International Commission on Radiological Protection (ICRP), the basic principles and recommendations for radiation protection of the NCRP are closely coupled with those of the ICRP. Thus, the fundamental principles of justification, optimization, and dose limitation as initially stated in ICRP Publication 26 have been adopted and applied by the NCRP in its recommendations. ICRP and NCRP recommendations on dose limitation for the general public and for occupationally exposed individuals are based on the same analyses of radiation risk, and, while similar, there are differences reflecting the aspects of radiation application and exposure circumstances unique to the United States. The NCRP has recently extended its guidance to address exposure to individuals engaged in space activities. Several reports have been issued or are in preparation to provide recommendations on dose limitation and the development of radiation safety programs to apply the radiation protection principles in space activities. The biological basis for these recommendations is provided in these and accompanying NCRP reports. Recommendations for the application of basic radiation protection principles have been made in many reports over the years. Those that are most current appear in approximately 50 reports published in the last 15 y. These address radiation safety practices in industrial and medical institutions, control of radionuclides in the environment, protection of the public, and assessment of radiation risk. Some of the aspects of these recommendations will be discussed. Current recommendations related to radiation safety practice are based

  10. Life-history interviews

    DEFF Research Database (Denmark)

    Adriansen, Hanne Kirstine

    2010-01-01

    My first encounter with life history research was during my Ph.D. research. This concerned a multi-method study of nomadic mobility in Senegal. One method stood out as yielding the most interesting and in-depth data: life story interviews using a time line. I made interviews with the head of the...... across cultures and disciplines and for my work as a management consultant. Naturally, I would include the tool for my students in educational psychology when I began teaching a course on qualitative interviews last semester. Large was my surprise when I failed to find any references to the specific time...... a time line in qualitative interviews. I first presented the paper on a conference on life history research at Karlstad University in November 2010. My main purpose was to establish whether a paper discussing the use of time line interviews should be placed in the context of a life history research...

  11. User Interface History

    DEFF Research Database (Denmark)

    Jørgensen, Anker Helms; Myers, Brad A

    2008-01-01

    User Interfaces have been around as long as computers have existed, even well before the field of Human-Computer Interaction was established. Over the years, some papers on the history of Human-Computer Interaction and User Interfaces have appeared, primarily focusing on the graphical interface era...... and early visionaries such as Bush, Engelbart and Kay. With the User Interface being a decisive factor in the proliferation of computers in society and since it has become a cultural phenomenon, it is time to paint a more comprehensive picture of its history. This SIG will investigate the possibilities...... of  launching a concerted effort towards creating a History of User Interfaces. ...

  12. Gestational Diabetes Mellitus Worsens the Profile of Cardiometabolic Risk Markers and Decrease Indexes of Beta-Cell Function Independently of Insulin Resistance in Nondiabetic Women with a Parental History of Type 2 Diabetes

    Directory of Open Access Journals (Sweden)

    Alina Sokup

    2014-01-01

    Full Text Available Background. Women with a history of both parental type 2 diabetes (pt2DM and previous gestational diabetes (pGDM represent a group at high risk of cardiovascular events. We hypothesized that pGDM changes cardiometabolic risk markers levels as well as theirs associations with glucose indices in nondiabetic pt2DM women. Methods. Anthropometric parameters, glucose regulation (OGTT, insulin resistance (HOMA-IR, beta-cell function, lipid levels, parameters of endothelial dysfunction, and inflammation were evaluated in 55 women with pt2DM, 40 with both pt2DM and pGDM 2–24 months postpartum, and 35 controls. Results. Prediabetes was diagnosed more frequently in women with both pt2DM and pGDM in comparison with women with only pt2DM (10 versus 8, P=0.04. The pGDM group had higher LDL-cholesterol, sICAM-1, tPa Ag, fibrinogen, and lower beta-cell function after adjustment for HOMA-IR, in comparison with pt2DM group. In pt2DM group postchallenge glucose correlated independently with hsCRP and in pGDM group fasting glucose with HOMA-IR. Conclusions. pGDM exerts a combined effect on cardiometabolic risk markers in women with pt2DM. In these women higher LDL-cholesterol, fibrinogen, sICAM-1, tPa Ag levels and decreased beta cell function are associated with pGDM independently of HOMA-IR index value. Fasting glucose is an important cardiometabolic risk marker and is independently associated with HOMA-IR.

  13. Our nuclear history

    International Nuclear Information System (INIS)

    The article on nuclear history is contained in a booklet on the Revised Nuffield Advanced Physics Course. The author shows how the difficult decisions about energy supplies at the end of the twentieth century can be seen as a consequence of the history and evolution of the Universe and of life, and mankind's activities on earth. The topics discussed include:-the origin of the Universe, formation of light elements, formation of carbon and oxygen, supernovae and nuclear equilibrium, formation of planets, development of life on earth, mankind and the use of fuels, and the nuclear valley. (UK)

  14. History of psychology.

    Science.gov (United States)

    Weidman, Nadine

    2016-02-01

    The editor of History of Psychology discusses her plan to vary the journal's content and expand its scope in specific ways. The first is to introduce a "Spotlight" feature, a relatively brief, provocative thought piece that might take one of several forms. Along with this new feature, she hopes further to broaden the journal's coverage and its range of contributors. She encourages submissions on the history of the psy-sciences off the beaten path. Finally, she plans to continue the journal's tradition of special issues, special sections, and essay reviews of two or more important recently published books in the field. (PsycINFO Database Record PMID:26844648

  15. History, Memory and Film

    DEFF Research Database (Denmark)

    Bondebjerg, Ib

    In this paper I discuss history and memory from a theoretical and philosophical point of view and the non-fiction and fiction aspects of historical representation. I use Edgar Reitz’ monumental work Heimat 1-3 (and his recent film Die Andere Heimat) as examples of very different transformative...... historical narratives. In terms of narrative construction and aesthetic form the Heimat-project challenges the dominant forms of historical fiction. By combining personal memory, everyday life and collective memory and a more indirect way of representing factual history Reitz wants to transform our look at...

  16. 48 CFR 49.113 - Cost principles.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Cost principles. 49.113 Section 49.113 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION CONTRACT MANAGEMENT TERMINATION OF CONTRACTS General Principles 49.113 Cost principles. The cost principles and procedures in...

  17. PRINCIPLES OF NOTARIAL ACTIVITY IN UKRAINE

    OpenAIRE

    Ільєва, Н. В.

    2015-01-01

    The article focuses on defining the principles of notarial activity. The author allocated and analyzed the general principles of activity of all bodies of the public power, the special principles which characterize specifics of notarial activity, the principles of administrative and legal regulation of notarial activity.

  18. Rhetoric and History in Brian Friel’s Making History

    OpenAIRE

    Manfredi Bernardini

    2014-01-01

    This paper proposes an analysis of the rhetorical devices of representation and recording of history, investigated and deconstructed by the so-called "history play" Making History, written by Brian Friel and performed by the Field Day Theatre Company in 1988. The play tells of the heroic deeds of Hugh O’ Neill, a Sixteenth century Ulster gaelic Lord, intertwining his personal facts with the crucial events in Irish History.Friel rediscovers a paradigmatic figure in Irish history, using the the...

  19. The principles of garden design

    OpenAIRE

    Turner, Tom

    2008-01-01

    This ebook explains the 3 classic design principles: gardens should be useful, gardens should be well-made and gardens should be beautiful. They derive from Vitruvius and have influenced the design of gardens since ancient times and are as important today as they have always been.

  20. The Principle of Structural Reciprocity

    DEFF Research Database (Denmark)

    Pugnale, Alberto; Parigi, Dario; Kirkegaard, Poul Henning; Sassone, Mario SASSONE

    2011-01-01

    This paper deals with the principle of structural reciprocity, considering its origins in both Occidental and Orient culture and aiming to highlight the definition, main peculiarities and interesting aspects of such concept referring to its application to the world of construction. Issues spanning...

  1. Entropy and the uncertainty principle

    CERN Document Server

    Frank, Rupert L

    2011-01-01

    We generalize, improve and unify theorems of Rumin, and Maassen--Uffink about classical entropies associated to quantum density matrices. These theorems refer to the classical entropies of the diagonals of a density matrix in two different bases. Thus they provide a kind of uncertainty principle. Our inequalities are sharp because they are exact in the high-temperature or semi-classical limit.

  2. Basic safety principles: Lessons learned

    International Nuclear Information System (INIS)

    The presentation reviews the following issues: basic safety principles and lessons learned; some conclusions from the Kemeny report on the accident at TMI; some recommendations from the Kemeny report on the accident at TMI; conclusions and recommendations from the Rogovin report on the accident on TMI; instrumentation deficiencies (from Rogovin report)

  3. Demonstrating Fermat's Principle in Optics

    Science.gov (United States)

    Paleiov, Orr; Pupko, Ofir; Lipson, S. G.

    2011-01-01

    We demonstrate Fermat's principle in optics by a simple experiment using reflection from an arbitrarily shaped one-dimensional reflector. We investigated a range of possible light paths from a lamp to a fixed slit by reflection in a curved reflector and showed by direct measurement that the paths along which light is concentrated have either…

  4. Contextuality: Wheeler's universal regulating principle

    CERN Document Server

    Durham, Ian T

    2013-01-01

    In this essay I develop quantum contextuality as a potential candidate for Wheeler's universal regulating principle, arguing -- \\textit{contrary} to Wheeler -- that this ultimately implies that `bit' comes from `it.' In the process I develop a formal definition of physical determinism in the languages of domain theory and category theory.

  5. Thermionics basic principles of electronics

    CERN Document Server

    Jenkins, J; Ashhurst, W

    2013-01-01

    Basic Principles of Electronics, Volume I : Thermionics serves as a textbook for students in physics. It focuses on thermionic devices. The book covers topics on electron dynamics, electron emission, and the themionic vacuum diode and triode. Power amplifiers, oscillators, and electronic measuring equipment are studied as well. The text will be of great use to physics and electronics students, and inventors.

  6. Comments on field equivalence principles

    DEFF Research Database (Denmark)

    Appel-Hansen, Jørgen

    1987-01-01

    It is pointed Out that often-used arguments based on a short-circuit concept in presentations of field equivalence principles are not correct. An alternative presentation based on the uniqueness theorem is given. It does not contradict the results obtained by using the short-circuit concept but...

  7. The Oscillator Principle of Nature

    DEFF Research Database (Denmark)

    Lindberg, Erik

    2012-01-01

    Oscillators are found on all levels in Nature. The general oscillator concept is defined and investigated. Oscillators may synchronize into fractal patterns. Apparently oscillators are the basic principle in Nature. The concepts of zero and infinite are discussed. Electronic manmade oscillators are...

  8. Nuclear fusion - principles and applications

    International Nuclear Information System (INIS)

    This report describes the principles of nuclear fusion, plasma properties and approaches for the generation of energy from the fusion of hydrogen nuclei. It is intended for high-school students and laymen interested in a broad prespective on the subject matter and current state-of-affairs. (author)

  9. Fermat Principle for spinning light

    OpenAIRE

    Duval, C.; Horvathy, Z.; Horvathy, P. A.

    2005-01-01

    Mimicking the description of spinning particles in General Relativity, the Fermat Principle is extended to spinning photons. Linearization of the resulting Papapetrou-Souriau type equations yields the semiclassical model used recently to derive the ``Optical Hall Effect'' (alias the ``Optical Magnus Effect'') for polarized light.

  10. The splitting principle and singularities

    OpenAIRE

    Kovács, Sándor J.

    2011-01-01

    The splitting principle states that morphisms in a derived category do not "split" accidentally. This has been successsfully applied in several characterizations of rational, DB, and other singularities. In this article I prove a general statement that implies many of the previous individual statements and improves some of the characterizations in the process.

  11. Electrical craft principles, v.2

    CERN Document Server

    Whitfield, John

    2008-01-01

    The two volumes of Whitfield's Electrical Craft Principles have been substantially revised and updated in 2008, reflecting changes in practice and legislation (e.g. BS 7671/Requirements for Electrical Installations). Volume 2 in particular has new material to accompany course changes. The volumes are presented in a new format, are highly illustrated and contain full problems and solutions.

  12. On the Dirichlet's Box Principle

    Science.gov (United States)

    Poon, Kin-Keung; Shiu, Wai-Chee

    2008-01-01

    In this note, we will focus on several applications on the Dirichlet's box principle in Discrete Mathematics lesson and number theory lesson. In addition, the main result is an innovative game on a triangular board developed by the authors. The game has been used in teaching and learning mathematics in Discrete Mathematics and some high schools in…

  13. Structuring Principles for the Designer

    DEFF Research Database (Denmark)

    Miller, Thomas Dedenroth; Pedersen, Per Erik Elgård

    1998-01-01

    This paper suggests a list of structuring principles that support the designer in making alternative concepts for product architectures. Different architectures may support different points of diversification in the product life-cycle. The aim is to balance reuse of resources and reduction of...

  14. Design Principles for Hybrid Ventilation

    DEFF Research Database (Denmark)

    Heiselberg, Per

    For many years mechanical and natural ventilation systems have developed separately. Naturally, the next step in this development is the development of ventilation concepts that utilize and combine the best features from each system to create a new type of ventilation system -Hybrid Ventilation....... The hybrid ventilation concepts, design challenges and - principles are discussed and illustrated by four building examples....

  15. Electrical craft principles, v.1

    CERN Document Server

    Whitfield, John

    2008-01-01

    The two volumes of Whitfield's Electrical Craft Principles have been substantially revised and updated in 2008, reflecting changes in practice and legislation (e.g. BS 7671/Requirements for Electrical Installations). The volumes are presented in a new format, are highly illustrated and contain full problems and solutions.

  16. The Application of Cooperation Principle and Politeness Principle in Oral Teaching

    Institute of Scientific and Technical Information of China (English)

    石洁

    2014-01-01

    The pragmatic principle that people should comply with in communicative activities are the principles of cooperation and politeness principle. The principles of cooperation play a regulatory role in communication while politeness principle actually has a greater binding. In teaching, teachers should always teach basing on language and make students understand the Cooperative Principle and Politeness Principle in pragmatics in order to improve oral communication skills.

  17. History of cosmetics

    Directory of Open Access Journals (Sweden)

    Chaudhri S

    2009-01-01

    Full Text Available Cosmetics have become part of our routine. Their use has increased significantly in recent years however the continuous use of cosmetics over prolonged time may result into various undesirable effects, which may be serious at times. This review is an attempt to trace out the history of cosmetics used by different civilizations over centuries

  18. Didactics of History

    DEFF Research Database (Denmark)

    Haue, Harry

    The book consits of five chapters about  formation and education in Denmark over the last two centuries. The developement of history teaching is especially stressed. The guiding concept for the upper secondary education has since 1850 been 'general character formation'. The book is an edited...

  19. Yearbooks as History Books.

    Science.gov (United States)

    Kennedy, Jack

    1996-01-01

    Provides an eight-step plan to help yearbook production staffs research the history of their school and integrate it into the present, allowing students to see the "big picture" of how their school has affected and continues to affect the community in which they reside. (PA)

  20. Diving Into History

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    Three divers have made history at the 13th FINA World Championships held in Rome on July 17-August 2. Guo Jingjing, the Chinese diving queen who clinched the gold in the women’s 3-meter springboard on July 21, became the first

  1. Black History Speech

    Science.gov (United States)

    Noldon, Carl

    2007-01-01

    The author argues in this speech that one cannot expect students in the school system to know and understand the genius of Black history if the curriculum is Eurocentric, which is a residue of racism. He states that his comments are designed for the enlightenment of those who suffer from a school system that "hypocritically manipulates Black…

  2. CERN's Early History Revisited

    CERN Multimedia

    Schopper, Herwig Franz; Krige, Gerhard John

    2005-01-01

    As a member of the group of historians charged to write the history of the founding of CERN, John Krige particularly underlines the important role I.I. Rabi played. The first author, former Director General of CERN add a few comments. S.A. Khan gives precisions about the role played by E. Amaldi and P. Auger; then J. Krige replies

  3. Walking Out of History

    Institute of Scientific and Technical Information of China (English)

    GARMARDORJE; CUIFENG

    2002-01-01

    EDITOR’S NOTE: Barkor Street around Jokhang Monastery has a history of 1,300 years. The age-old street, however, has found the fountain of youth and takes on a new outlook today. And the fountain of youth is none other than the ongoing reform and opening program.

  4. TELEOLOGY AND HISTORY

    Directory of Open Access Journals (Sweden)

    Artur Bispo Santos Neto

    2011-02-01

    Full Text Available Considering that the ratio and empiricism fetishization leads to the development of an habitual tenderness to the supra-sensible things and the sensible things, the current paper has as starting point the critics to the notion of history that passes by the philosophy of history and as this ends up having repercussions in the inner of its own Marxism in a revisionist and dogmatic manner, to the proportion that it tries to confirm the existence of a mechanistic determination or of a necessary connexion in the development of the history. The predominance of the teleology, as fundamental category in the history fetishization for the idealist conception, expresses the hierarchical amalgam in the supervalorization of the logical in detriment of the ontological. During the reading of this text, it is affirmed that in the Marxian theory does not exist any possibility of teleology affirmation in society and in nature and that only in the labor, while criterion of social praxis, subsists a real dialectical relation between teleology and causality

  5. Ancient Egypt: History 380.

    Science.gov (United States)

    Turk, Laraine D.

    "Ancient Egypt," an upper-division, non-required history course covering Egypt from pre-dynastic time through the Roman domination is described. General descriptive information is presented first, including the method of grading, expectation of student success rate, long-range course objectives, procedures for revising the course, major course…

  6. History of cosmetics

    OpenAIRE

    Chaudhri S; Jain N

    2009-01-01

    Cosmetics have become part of our routine. Their use has increased significantly in recent years however the continuous use of cosmetics over prolonged time may result into various undesirable effects, which may be serious at times. This review is an attempt to trace out the history of cosmetics used by different civilizations over centuries

  7. Living in history

    DEFF Research Database (Denmark)

    Brown, Norman R.; Lee, Peter J.; Krslak, Mirna;

    2009-01-01

    Foreslår et paradigme - "Living in history" - til undersøgelse af forholdet mellem samtidshistorie og selvbiografisk hukommelse. Metoden spørger ikke direkte og altså ikke til den anknytning, man bevidst ville vælge at fremhæve, men undersøger indirekte, om der spontant associeres til samtidsbegi...

  8. Life History and Identity

    Science.gov (United States)

    Tierney, William G.

    2013-01-01

    This article uses the life history method to chronicle the challenges of a low-income, first-generation student en route to college. The paper addresses three questions: how Manuel navigates college and related topics such as roommates, family, and money; how he creates social networks; and how he works with adults such as teachers and…

  9. History of vaccination

    OpenAIRE

    Plotkin, Stanley

    2014-01-01

    Vaccines have a history that started late in the 18th century. From the late 19th century, vaccines could be developed in the laboratory. However, in the 20th century, it became possible to develop vaccines based on immunologic markers. In the 21st century, molecular biology permits vaccine development that was not possible before.

  10. History and Civility

    Science.gov (United States)

    Schaefer, Larry

    2015-01-01

    Larry Schaefer's history of civility is a succinct summary of the implicit and evolving definitions of civility over 2500 years of civilization. Beginning with the Romans and the root word "civitas," meaning the rights and duties of citizenship, civility appears in classical literature as integral to the roots of democracy in the context…

  11. Figuring Out Art History

    CERN Document Server

    Schich, Maximilian

    2015-01-01

    World population and the number of cultural artifacts are growing exponentially or faster, while cultural interaction approaches the fidelity of a global nervous system. Every day hundreds of millions of images are loaded into social networks by users all over the world. As this myriad of new artifacts veils the view into the past, like city lights covering the night sky, it is easy to forget that there is more than one Starry Night, the painting by Van Gogh. Like in ecology, where saving rare species may help us in treating disease, art and architectural history can reveal insights into the past, which may hold keys to our own future. With humanism under threat, facing the challenge of understanding the structure and dynamics of art and culture, both qualitatively and quantitatively, is more crucial now than it ever was. The purpose of this article is to provide perspective in the aim of figuring out the process of art history - not art history as a discipline, but the actual history of all made things, in t...

  12. American History (an introduction)

    DEFF Research Database (Denmark)

    Nye, David Edwin

    I et letforståeligt engelsk giver professor David Nye en fængende præsentation af amerikansk historie fra den tidlige kolonisationsperiode til præsident Obama. Bogen giver et helhedsportræt af perioderne og inkluderer til hver periode en kortfattet præsentation af kultur- og litteraturhistorien....

  13. Natural history of COPD

    DEFF Research Database (Denmark)

    Vestbo, Jørgen; Lange, Peter

    2016-01-01

    The natural history of chronic obstructive pulmonary disease (COPD) is usually described with a focus on change in forced expiratory volume in 1 s (FEV1 ) over time as this allows for exploration of risk factors for an accelerated decline-and thus of developing COPD. From epidemiological studies we...

  14. History in the Flesh

    DEFF Research Database (Denmark)

    Bencard, Adam

    drevet af en historisering, en vilje til at placere historie hvor der før var biologi.   Denne afhandling undersøger denne interesse i kroppen gennem en analyse af hvad jeg kalder den historiserede krop som diskursiv figur. Den historiserede krop er ikke et klart aftegnet koncept eller en skarp afgrænset...

  15. Access and History

    DEFF Research Database (Denmark)

    Jensen, Erik Granly

    2012-01-01

    Like many other major European media corporations the Danish Broadcasting Corporation (DR) has begun the digitisation of its audio-visual archives. This transformation from analogue to digital archives raises a number of questions regarding the archive specific character, history and content...

  16. The history of Kevatron

    International Nuclear Information System (INIS)

    During the Annual meeting of the Asociacion Fisica Argentina, hold between September 20 and 22, 1963, Dr. Wolfgang Meckbach made a communication officially introducing to the argentine scientific community the Kevatron accelerator, build in the Bariloche Atomic Center: a ions accelerator of the Cockcroft-Walton type. The history of its construction and installation is related. (author)

  17. KER-2 tube history

    Energy Technology Data Exchange (ETDEWEB)

    Banister, W.C.

    1963-08-16

    Zirconium process tube No. 1986 was installed in KE Reactor tube channel No. 2864 on April 16, 1959. This report describes the history and the conditions to which it was exposed during its residence in the reactor. The tube was removed on May 31, 1963.

  18. Principles of justice in health care rationing

    OpenAIRE

    Cookson, R; Dolan, P.

    2000-01-01

    This paper compares and contrasts three different substantive (as opposed to procedural) principles of justice for making health care priority-setting or "rationing" decisions: need principles, maximising principles and egalitarian principles. The principles are compared by tracing out their implications for a hypothetical rationing decision involving four identified patients. This decision has been the subject of an empirical study of public opinion based on small-group discussions, which fo...

  19. On a Quest for Principles, Big Data in Hand.

    Science.gov (United States)

    2016-05-19

    Cell editor Karen Carniol discusses the excitement and challenges of the "big data" era and how quantitative approaches reveal important biological principles with Galit Lahav, Gürol Süel, and Olga Troyanskaya. Annotated excerpts from this conversation are presented below, and the full conversation is available with the article online. PMID:27203104

  20. Beyond the principles of bioethics: facing the consequences of fundamental moral disagreement

    OpenAIRE

    H. Tristram Engelhardt

    2012-01-01

    http://dx.doi.org/10.5007/1677-2954.2012v11n1p13 Given intractable secular moral pluralism, the force and significance of the four principles (autonomy, beneficence, non-maleficence, and justice) of Tom Beauchamp and James Childress must be critically re-considered. This essay examines the history of the articulation of these four principles of bioethics, showing why initially there was an illusion of a common morality that led many to hold that the principles could give guidance across cultu...