WorldWideScience

Sample records for cell evolving concepts

  1. PERFORMANCE - AN EVOLVING CONCEPT

    OpenAIRE

    Assist. Mirela-Oana Pintea Ph.D Student; Lect. Monica-Violeta Achim

    2010-01-01

    The concept of performance is a problematic concept and will remain so as long as the definition of company performance varies depending on the interests of users of information. On this consideration, no consensus was reached regarding the definition, methodology and performance models used. Defining this concept is realized in accordance with its objectives of users of information, while the methodology and models used are influenced by legal regulations and management policies. The approac...

  2. Evolving Ethical Concepts

    Science.gov (United States)

    Potter, Van Rensselaer

    1977-01-01

    Discusses the role of the scientist in changing ethical concepts from simple interpersonal and theological imperatives towards "survival imperatives that must form the core of environmental bioethics." (CS)

  3. Evolving Concepts of Asthma

    Science.gov (United States)

    Ray, Anuradha; Wenzel, Sally E.

    2015-01-01

    Our understanding of asthma has evolved over time from a singular disease to a complex of various phenotypes, with varied natural histories, physiologies, and responses to treatment. Early therapies treated most patients with asthma similarly, with bronchodilators and corticosteroids, but these therapies had varying degrees of success. Similarly, despite initial studies that identified an underlying type 2 inflammation in the airways of patients with asthma, biologic therapies targeted toward these type 2 pathways were unsuccessful in all patients. These observations led to increased interest in phenotyping asthma. Clinical approaches, both biased and later unbiased/statistical approaches to large asthma patient cohorts, identified a variety of patient characteristics, but they also consistently identified the importance of age of onset of disease and the presence of eosinophils in determining clinically relevant phenotypes. These paralleled molecular approaches to phenotyping that developed an understanding that not all patients share a type 2 inflammatory pattern. Using biomarkers to select patients with type 2 inflammation, repeated trials of biologics directed toward type 2 cytokine pathways saw newfound success, confirming the importance of phenotyping in asthma. Further research is needed to clarify additional clinical and molecular phenotypes, validate predictive biomarkers, and identify new areas for possible interventions. PMID:26161792

  4. The Ever-Evolving Concept of the Cancer Stem Cell in Pancreatic Cancer

    Directory of Open Access Journals (Sweden)

    Sandra Valle

    2018-01-01

    Full Text Available Pancreatic ductal adenocarcinoma (PDAC, the most common type of pancreatic cancer, is the 4th most frequent cause of cancer-related death worldwide, primarily due to the inherent chemoresistant nature and metastatic capacity of this tumor. The latter is believed to be mainly due to the existence of a subpopulation of highly plastic “stem”-like cells within the tumor, known as cancer stem cells (CSCs, which have been shown to have unique metabolic, autophagic, invasive, and chemoresistance properties that allow them to continuously self-renew and escape chemo-therapeutic elimination. As such, current treatments for the majority of PDAC patients are not effective and do not significantly impact overall patient survival (<7 months as they do not affect the pancreatic CSC (PaCSC population. In this context, it is important to highlight the need to better understand the characteristics of the PaCSC population in order to develop new therapies to target these cells. In this review, we will provide the latest updates and knowledge on the inherent characteristics of PaCSCs, particularly their unique biological properties including chemoresistance, epithelial to mesenchymal transition, plasticity, metabolism and autophagy.

  5. Idiopathic pulmonary fibrosis: evolving concepts.

    Science.gov (United States)

    Ryu, Jay H; Moua, Teng; Daniels, Craig E; Hartman, Thomas E; Yi, Eunhee S; Utz, James P; Limper, Andrew H

    2014-08-01

    Idiopathic pulmonary fibrosis (IPF) occurs predominantly in middle-aged and older adults and accounts for 20% to 30% of interstitial lung diseases. It is usually progressive, resulting in respiratory failure and death. Diagnostic criteria for IPF have evolved over the years, and IPF is currently defined as a disease characterized by the histopathologic pattern of usual interstitial pneumonia occurring in the absence of an identifiable cause of lung injury. Understanding of the pathogenesis of IPF has shifted away from chronic inflammation and toward dysregulated fibroproliferative repair in response to alveolar epithelial injury. Idiopathic pulmonary fibrosis is likely a heterogeneous disorder caused by various interactions between genetic components and environmental exposures. High-resolution computed tomography can be diagnostic in the presence of typical findings such as bilateral reticular opacities associated with traction bronchiectasis/bronchiolectasis in a predominantly basal and subpleural distribution, along with subpleural honeycombing. In other circumstances, a surgical lung biopsy may be needed. The clinical course of IPF can be unpredictable and may be punctuated by acute deteriorations (acute exacerbation). Although progress continues in unraveling the mechanisms of IPF, effective therapy has remained elusive. Thus, clinicians and patients need to reach informed decisions regarding management options including lung transplant. The findings in this review were based on a literature search of PubMed using the search terms idiopathic pulmonary fibrosis and usual interstitial pneumonia, limited to human studies in the English language published from January 1, 2000, through December 31, 2013, and supplemented by key references published before the year 2000. Copyright © 2014 Mayo Foundation for Medical Education and Research. Published by Elsevier Inc. All rights reserved.

  6. Evolvability Is an Evolved Ability: The Coding Concept as the Arch-Unit of Natural Selection.

    Science.gov (United States)

    Janković, Srdja; Ćirković, Milan M

    2016-03-01

    Physical processes that characterize living matter are qualitatively distinct in that they involve encoding and transfer of specific types of information. Such information plays an active part in the control of events that are ultimately linked to the capacity of the system to persist and multiply. This algorithmicity of life is a key prerequisite for its Darwinian evolution, driven by natural selection acting upon stochastically arising variations of the encoded information. The concept of evolvability attempts to define the total capacity of a system to evolve new encoded traits under appropriate conditions, i.e., the accessible section of total morphological space. Since this is dependent on previously evolved regulatory networks that govern information flow in the system, evolvability itself may be regarded as an evolved ability. The way information is physically written, read and modified in living cells (the "coding concept") has not changed substantially during the whole history of the Earth's biosphere. This biosphere, be it alone or one of many, is, accordingly, itself a product of natural selection, since the overall evolvability conferred by its coding concept (nucleic acids as information carriers with the "rulebook of meanings" provided by codons, as well as all the subsystems that regulate various conditional information-reading modes) certainly played a key role in enabling this biosphere to survive up to the present, through alterations of planetary conditions, including at least five catastrophic events linked to major mass extinctions. We submit that, whatever the actual prebiotic physical and chemical processes may have been on our home planet, or may, in principle, occur at some time and place in the Universe, a particular coding concept, with its respective potential to give rise to a biosphere, or class of biospheres, of a certain evolvability, may itself be regarded as a unit (indeed the arch-unit) of natural selection.

  7. Life cycle planning: An evolving concept

    International Nuclear Information System (INIS)

    Moore, P.J.R.; Gorman, I.G.

    1994-01-01

    Life-cycle planning is an evolving concept in the management of oil and gas projects. BHP Petroleum now interprets this idea to include all development planning from discovery and field appraisal to final abandonment and includes safety, environmental, technical, plant, regulatory, and staffing issues. This article describes in the context of the Timor Sea, how despite initial successes and continuing facilities upgrades, BHPP came to perceive that current operations could be the victim of early development successes, particularly in the areas of corrosion and maintenance. The search for analogies elsewhere lead to the UK North Sea, including the experiences of Britoil and BP, both of which performed detailed Life of Field studies in the later eighties. These materials have been used to construct a format and content for total Life-cycle plans in general and the social changes required to ensure their successful application in Timor Sea operations and deployment throughout Australia

  8. Advances and Evolving Concepts in Allergic Asthma.

    Science.gov (United States)

    Tung, Hui-Ying; Li, Evan; Landers, Cameron; Nguyen, An; Kheradmand, Farrah; Knight, J Morgan; Corry, David B

    2018-02-01

    Allergic asthma is a heterogeneous disorder that defies a unanimously acceptable definition, but is generally recognized through its highly characteristic clinical expression of dyspnea and cough accompanied by clinical data that document reversible or exaggerated airway constriction and obstruction. The generally rising prevalence of asthma in highly industrialized societies despite significant therapeutic advances suggests that the fundamental cause(s) of asthma remain poorly understood. Detailed analyses of both the indoor (built) and outdoor environments continue to support the concept that not only inhaled particulates, especially carbon-based particulate pollution, pollens, and fungal elements, but also many noxious gases and chemicals, especially biologically derived byproducts such as proteinases, are essential to asthma pathogenesis. Phthalates, another common class of chemical pollutant found in the built environment, are emerging as potentially important mediators or attenuators of asthma. Other biological products such as endotoxin have also been confirmed to be protective in both the indoor and outdoor contexts. Proasthmatic factors are believed to activate, and in some instances initiate, pathologic inflammatory cascades through complex interactions with pattern recognition receptors (PRRs) expressed on many cell types, but especially airway epithelial cells. PRRs initiate the release of proallergic cytokines such as interleukin (IL)-33, IL-25, and others that coordinate activation of innate lymphoid cells type 2 (ILC2), T helper type 2 cells, and immunoglobulin E-secreting B cells that together promote additional inflammation and the major airway remodeling events (airway hyperresponsiveness, mucus hypersecretion) that promote airway obstruction. Proteinases, with airway fungi and viruses being potentially important sources, are emerging as critically important initiators of these inflammatory cascades in part through their effects on clotting

  9. Lifelong learning: Established concepts and evolving values.

    Science.gov (United States)

    Talati, Jamsheer Jehangir

    2014-03-01

    To summarise the concepts critical for understanding the content and value of lifelong learning (LL). Ideas generated by personal experience were combined with those of philosophers, social scientists, educational institutions, governments and UNESCO, to facilitate an understanding of the importance of the basic concepts of LL. Autopoietic, continuous, self-determined, informal, vicarious, biographical, lifelong reflexive learning, from and for society, when supported by self-chosen formal courses, can build capacities and portable skills that allow useful responses to challenges and society's new structures of governance. The need for LL is driven by challenges. LL flows continuously in pursuit of one agenda, which could either be citizenship, as is conventional, or as this article proposes, health. LL cannot be wholly centred on vocation. Continuous medical education and continuous professional development, important in their own right, cannot supply all that is needed. LL aids society with its learning, and it requires an awareness of the environment and structures of society. It is heavily vicarious, draws on formal learning and relies for effectiveness on reflection, self-assessment and personal shaping of views of the world from different perspectives. Health is critical to rational thought and peace, and determines society's capacity to govern itself, and improve its health. LL should be reshaped to focus on health not citizenship. Therefore, embedding learning in society and environment is critical. Each urologist must develop an understanding of the numerous concepts in LL, of which 'biographicisation' is the seed that will promote innovative strategies.

  10. Atherosclerotic plaque rupture and thrombosis. Evolving concepts.

    Science.gov (United States)

    Fuster, V; Stein, B; Ambrose, J A; Badimon, L; Badimon, J J; Chesebro, J H

    1990-09-01

    Rupture of an atherosclerotic plaque associated with partial or complete thrombotic vessel occlusion is fundamental to the development of ischemic coronary syndromes. Plaques that produce only mild-to-moderate angiographic luminal stenosis are frequently those that undergo abrupt disruption, leading to unstable angina or acute myocardial infarction. Plaques with increased lipid content appear more prone to rupture, particularly when the lipid pool is localized eccentrically within the intima. Macrophages appear to play an important role in atherogenesis, perhaps by participating in the uptake and metabolism of lipoproteins, secretion of growth factors, and production of enzymes and toxic metabolites that may facilitate plaque rupture. In addition, the particular composition or configuration of a plaque and the hemodynamic forces to which it is exposed may determine its susceptibility to disruption. Exposure of collagen, lipids, and smooth muscle cells after plaque rupture leads to the activation of platelets and the coagulation cascade system. The resulting thrombus may lead to marked reduction in myocardial perfusion and the development of an unstable coronary syndrome, or it may become organized and incorporated into the diseased vessel, thus contributing to the progression of atherosclerosis. In unstable angina, plaque disruption leads to thrombosis, which is usually labile and results in only a transient reduction in myocardial perfusion. Release of vasoactive substances, arterial spasm, or increases in myocardial oxygen demand may contribute to ischemia. In acute myocardial infarction, plaque disruption results in a more persistent thrombotic vessel occlusion; the extent of necrosis depends on the size of the artery, the duration of occlusion, the presence of collateral flow, and the integrity of the fibrinolytic system. Thrombi that undergo lysis expose a highly thrombogenic surface to the circulating blood, which has the capacity of activating platelets and

  11. Evolving Concepts of Development through the Experience of ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    This project will explore the experiences of emerging and developing countries in order to identify how the concept of international development has evolved and where it they may be heading. It will do so through a series of workshops convening scholars and practitioners from both the developing and the industrialized ...

  12. Progress in evolving the state-level concept

    International Nuclear Information System (INIS)

    Cooley, J.N.

    2013-01-01

    The Department of Safeguards of the International Atomic Energy Agency has launched an important and ambitious project to further develop and implement the State-level concept. It means the development of State-level approaches that are customized for an individual State, meeting State-specific objectives. Further development of the State-level concept requires: 1) expanded use of State-specific factors and implementation of a structured acquisition path analysis to establish State-specific technical objectives and then prioritize them; 2) development of State-level approaches that specify and provide options for safeguards measures, both at Headquarters and in the field, for meeting these technical objectives; 3) identification of activities to be conducted over the course of a year in an annual implementation plan (AIP); and 4) ensuring the linkage between the State-evaluation process and the development and implementation of State-level approaches and AIPs. This project for evolving the State-level concept will result in safeguards implementation that is more objectives-based and information-driven. The paper is followed by the slides of the presentation. (A.C.)

  13. An evolving joint space campaign concept and the Army's role

    Science.gov (United States)

    Franke, Henry G., III

    1992-05-01

    This monograph examines the question of an evolving joint space campaign concept and the Army's role in it over the next 20 years. Analysis progresses logically through a series of topics in order to arrive at a complete picture of this evolutionary space campaign concept, as well as the Army's place in it. Space plays an increasingly important role in US military operations, particularly when tied together with advances in information management. The synergistic impact due to the combination of these two areas suggests a revolution in the nature of modern warfare which saw its emergence during the 1991 Gulf War. With this theme in mind, I review the Army's roles, missions, and historical involvement in space, then present technological opportunities and a perspective on investment strategies for military space. A detailed discussion of a near-term military space theory and current space doctrines supports the need for an accepted military space theory as a foundation for Joint and Service space doctrines, space campaign design and conduct, and space force generation. The basis for such a theory is established using Julian Corbett's maritime warfare theory as a point of departure, while recognizing that space as a unique military operating medium requires its own theory and a regime to govern the application of space forces.

  14. EVOLVE

    CERN Document Server

    Deutz, André; Schütze, Oliver; Legrand, Pierrick; Tantar, Emilia; Tantar, Alexandru-Adrian

    2017-01-01

    This book comprises nine selected works on numerical and computational methods for solving multiobjective optimization, game theory, and machine learning problems. It provides extended versions of selected papers from various fields of science such as computer science, mathematics and engineering that were presented at EVOLVE 2013 held in July 2013 at Leiden University in the Netherlands. The internationally peer-reviewed papers include original work on important topics in both theory and applications, such as the role of diversity in optimization, statistical approaches to combinatorial optimization, computational game theory, and cell mapping techniques for numerical landscape exploration. Applications focus on aspects including robustness, handling multiple objectives, and complex search spaces in engineering design and computational biology.

  15. New and evolving concepts in the neurotoxicology of lead

    International Nuclear Information System (INIS)

    White, L.D.; Cory-Slechta, D.A.; Gilbert, M.E.; Tiffany-Castiglioni, E.; Zawia, N.H.; Virgolini, M.; Rossi-George, A.; Lasley, S.M.; Qian, Y.C.; Basha, Md. Riyaz

    2007-01-01

    Lead (Pb) is a xenobiotic metal with no known essential function in cellular growth, proliferation, or signaling. Decades of research characterizing the toxicology of Pb have shown it to be a potent neurotoxicant, especially during nervous system development. New concepts in the neurotoxicology of Pb include advances in understanding the mechanisms and cellular specificity of Pb. Experimental studies have shown that stress can significantly alter the effects of Pb, effects that could potentially be mediated through alterations in the interactions of glucocorticoids with the mesocorticolimbic dopamine system of the brain. Elevated stress, with corresponding elevated glucocorticoid levels, has been postulated to contribute to the increased levels of many diseases and dysfunctions in low socioeconomic status populations. Cellular models of learning and memory have been utilized to investigate the potential mechanisms of Pb-induced cognitive deficits. Examination of long-term potentiation in the rodent hippocampus has revealed Pb-induced increases in threshold, decreases in magnitude, and shorter retention times of synaptic plasticity. Structural plasticity in the form of adult neurogenesis in the hippocampus is also impacted by Pb exposure. The action of Pb on glutamate release, NMDA receptor function, or structural plasticity may underlie perturbations in synaptic plasticity and contribute to learning impairments. In addition to providing insight into potential mechanisms of Pb-induced cognitive deficits, cellular models offer an opportunity to investigate direct effects of Pb on isolated biological substrates. A target of interest is the 78-kDa molecular chaperone glucose-regulated protein (GRP78). GRP78 chaperones the secretion of the cytokine interleukin-6 (IL-6) by astrocytes. In vitro evidence shows that Pb strongly binds to GRP78, induces GRP78 aggregation, and blocks IL-6 secretion in astroglial cells. These findings provide evidence for a significant

  16. Evolving concepts of heredity and genetics in orthodontics.

    Science.gov (United States)

    Carlson, David S

    2015-12-01

    The field of genetics emerged from the study of heredity early in the 20th century. Since that time, genetics has progressed through a series of defined eras based on a number of major conceptual and technical advances. Orthodontics also progressed through a series of conceptual stages over the past 100 years based in part on the ongoing and often circular debate about the relative importance of heredity (nature) and the local environment (nurture) in the etiology and treatment of malocclusion and dentofacial deformities. During the past 20 years, significant advancements in understanding the genomic basis of craniofacial development and the gene variants associated with dentofacial deformities have resulted in a convergence of the principles and concepts in genetics and in orthodontics that will lead to significant advancement of orthodontic treatments. Fundamental concepts from genetics and applied translational research in orthodontics provide a foundation for a new emphasis on precision orthodontics, which will establish a modern genomic basis for major improvements in the treatment of malocclusion and dentofacial deformities as well as many other areas of concern to orthodontists through the assessment of gene variants on a patient-by-patient basis. Copyright © 2015 American Association of Orthodontists. Published by Elsevier Inc. All rights reserved.

  17. From leeches to personalized medicine: evolving concepts in the management of polycythemia vera

    Science.gov (United States)

    Vannucchi, Alessandro M.

    2017-01-01

    Polycythemia vera is a clonal disorder of hematopoietic stem/progenitor cells. It manifests as an expansion of red cell mass. It is the most common chronic myeloproliferative neoplasm. In virtually all cases, it is characterized by a V617F point mutation in JAK2 exon 14 or less common mutations in exon 12. The landmark discovery of the autonomously activated JAK/STAT signaling pathway paved the way for the clinical development of the first target drug, the JAK1 and JAK2 inhibitor ruxolitinib. This is now approved for patients with resistance or intolerance to hydroxyurea. Phlebotomies and hydroxyurea are still the cornerstone of treatment, and aim to prevent the first appearance or recurrence of cardiovascular events that, together with progression to post-polycythemia vera myelofibrosis and leukemia, represent the main causes of death. Interferon-α is an alternative drug and has been shown to induce molecular remissions. It is currently undergoing phase III trials that might eventually lead to its approval for clinical use. The last few years have witnessed important advances towards an accurate early diagnosis of polycythemia vera, greater understanding of its pathogenesis, and improved patient management. This review will focus on the most recent achievements and will aim to unify the different concepts involved in a personalized approach to the patient with polycythemia vera. In spite of many recent advances in the understanding of its pathogenesis and improved disease management, polycythemia vera remains a life-threatening myeloproliferative neoplasm for which there is no cure. This review will present a critical overview of evolving concepts in diagnosis and treatment of this disease. PMID:27884974

  18. Evolving cell models for systems and synthetic biology.

    Science.gov (United States)

    Cao, Hongqing; Romero-Campero, Francisco J; Heeb, Stephan; Cámara, Miguel; Krasnogor, Natalio

    2010-03-01

    This paper proposes a new methodology for the automated design of cell models for systems and synthetic biology. Our modelling framework is based on P systems, a discrete, stochastic and modular formal modelling language. The automated design of biological models comprising the optimization of the model structure and its stochastic kinetic constants is performed using an evolutionary algorithm. The evolutionary algorithm evolves model structures by combining different modules taken from a predefined module library and then it fine-tunes the associated stochastic kinetic constants. We investigate four alternative objective functions for the fitness calculation within the evolutionary algorithm: (1) equally weighted sum method, (2) normalization method, (3) randomly weighted sum method, and (4) equally weighted product method. The effectiveness of the methodology is tested on four case studies of increasing complexity including negative and positive autoregulation as well as two gene networks implementing a pulse generator and a bandwidth detector. We provide a systematic analysis of the evolutionary algorithm's results as well as of the resulting evolved cell models.

  19. DNDO Analysis Cell Concept

    Energy Technology Data Exchange (ETDEWEB)

    Pagh, Richard T.; Dimmerling, Paul J.; Guillen, Zoe C.; Hoyt, Joel R.; Jarman, Kenneth D.; Kernan, Warnick J.; Reichmuth, Barbara A.; Rohlfing, Kerrie S.; Schweppe, John E.; Sego, Landon H.; Shergur, Jason M.; Siciliano, Edward R.; Woodring, Mitchell L.

    2014-03-12

    The Domestic Nuclear Detection Office (DNDO) has a mission of implementing rad/nuc interdiction capabilities for a managed and coordinated response to threats, integration of federal nuclear forensics programs, and coordinating the development of the global nuclear detection and reporting architecture. In the process of executing this mission, DNDO has generated substantial information, data, technical results, operational workflows and analytical tools. The effective utilization of these resources is an overarching goal of the organization. After nearly a decade of performing work, DNDO faces a challenge in capitalizing on the large amount of data, reports, processes, tools, and people. As new work is being planned, managers and researchers need to have an understating of what information has been collected, what tools are available, the collaborations which can be utilized to propel the work forward, processes to plan and execute, and how to present conclusions and results that can assist the government in making decisions. This type of challenge can be met through the use of a series of organized and connected elements which form a broader structure (cell) that promotes cross utilization of elements such that they can be tailored (analyzed) to fit the context of the problem to be solved. The development of an analysis cell for DNDO will address the challenges of utilizing existing elements, identifying gaps, annually reporting the performance of rad/nuc interdiction instrumentation, and planning the execution of future work.

  20. Evolving Microbial Communities in Cellulose-Fed Microbial Fuel Cell

    Directory of Open Access Journals (Sweden)

    Renata Toczyłowska-Mamińska

    2018-01-01

    Full Text Available The abundance of cellulosic wastes make them attractive source of energy for producing electricity in microbial fuel cells (MFCs. However, electricity production from cellulose requires obligate anaerobes that can degrade cellulose and transfer electrons to the electrode (exoelectrogens, and thus most previous MFC studies have been conducted using two-chamber systems to avoid oxygen contamination of the anode. Single-chamber, air-cathode MFCs typically produce higher power densities than aqueous catholyte MFCs and avoid energy input for the cathodic reaction. To better understand the bacterial communities that evolve in single-chamber air-cathode MFCs fed cellulose, we examined the changes in the bacterial consortium in an MFC fed cellulose over time. The most predominant bacteria shown to be capable electron generation was Firmicutes, with the fermenters decomposing cellulose Bacteroidetes. The main genera developed after extended operation of the cellulose-fed MFC were cellulolytic strains, fermenters and electrogens that included: Parabacteroides, Proteiniphilum, Catonella and Clostridium. These results demonstrate that different communities evolve in air-cathode MFCs fed cellulose than the previous two-chamber reactors.

  1. Surgical timing of treating injured extremities: an evolving concept of urgency.

    Science.gov (United States)

    Crist, Brett D; Ferguson, Tania; Murtha, Yvonne M; Lee, Mark A

    2013-01-01

    The management of some orthopaedic extremity injuries has changed over the past decade because of changing resource availability and the risks of complications. It is helpful to review the current literature regarding orthopaedic extremity emergencies and urgencies. The effects of the techniques of damage control orthopaedic techniques and the concept of the orthopaedic trauma room have also affected the management of these injuries. The available literature indicates that the remaining true orthopaedic extremity emergencies include compartment syndrome and vascular injuries associated with fractures and dislocations. Orthopaedic urgencies include open fracture management, femoral neck fractures in young patients treated with open reduction and internal fixation, and talus fractures that are open or those with impending skin compromise. Deciding when the definitive management of orthopaedic extremity injuries will occur has evolved as the concept of damage control orthopaedics has become more commonly accepted. Patient survival rates have improved with current resuscitative protocols. Definitive fixation of extremity injuries should be delayed until the patient's physiologic and extremity soft-tissue status allows for appropriate definitive management while minimizing the risks of complications. In patients with semiurgent orthopaedic injuries, the use of an orthopaedic trauma room has led to more efficient care of patients, fewer complications, and better time management for surgeons who perform on-call service for patients with traumatic orthopaedic injuries.

  2. What Causes Environmental Inequalities and Related Health Effects? An Analysis of Evolving Concepts

    Science.gov (United States)

    Kruize, Hanneke; Droomers, Mariël; van Kamp, Irene; Ruijsbroek, Annemarie

    2014-01-01

    Early environmental justice studies were exposure-oriented, lacked an integrated approach, and did not address the health impact of environmental inequalities. A coherent conceptual framework, needed to understand and tackle environmental inequalities and the related health effects, was lacking. We analyzed the more recent environmental justice literature to find out how conceptual insights have evolved. The conceptual framework of the WHO Commission on Social Determinants of Health (CSDH) was analyzed for additional explanations for environmental inequalities and the related health effects. This paper points out that recent environmental justice studies have broadened their scope by incorporating a broader set of physical and social environmental indicators, and by focusing on different geographic levels and on health impacts of environmental inequalities. The CSDH framework provided additional elements such as the role of structural determinants, the role of health-related behavior in relation to the physical and social environment, access to health care, as well as the life course perspective. Incorporating elements of the CSDH framework into existing environmental justice concepts, and performing more empirical research on the interactions between the different determinants at different geographical levels would further improve our understanding of environmental inequalities and their health effects and offer new opportunities for policy action. PMID:24886752

  3. What Causes Environmental Inequalities and Related Health Effects? An Analysis of Evolving Concepts

    Directory of Open Access Journals (Sweden)

    Hanneke Kruize

    2014-05-01

    Full Text Available Early environmental justice studies were exposure-oriented, lacked an integrated approach, and did not address the health impact of environmental inequalities. A coherent conceptual framework, needed to understand and tackle environmental inequalities and the related health effects, was lacking. We analyzed the more recent environmental justice literature to find out how conceptual insights have evolved. The conceptual framework of the WHO Commission on Social Determinants of Health (CSDH was analyzed for additional explanations for environmental inequalities and the related health effects. This paper points out that recent environmental justice studies have broadened their scope by incorporating a broader set of physical and social environmental indicators, and by focusing on different geographic levels and on health impacts of environmental inequalities. The CSDH framework provided additional elements such as the role of structural determinants, the role of health-related behavior in relation to the physical and social environment, access to health care, as well as the life course perspective. Incorporating elements of the CSDH framework into existing environmental justice concepts, and performing more empirical research on the interactions between the different determinants at different geographical levels would further improve our understanding of environmental inequalities and their health effects and offer new opportunities for policy action.

  4. Improved best estimate plus uncertainty methodology including advanced validation concepts to license evolving nuclear reactors

    International Nuclear Information System (INIS)

    Unal, Cetin; Williams, Brian; McClure, Patrick; Nelson, Ralph A.

    2010-01-01

    Many evolving nuclear energy programs plan to use advanced predictive multi-scale multi-physics simulation and modeling capabilities to reduce cost and time from design through licensing. Historically, the role of experiments was primary tool for design and understanding of nuclear system behavior while modeling and simulation played the subordinate role of supporting experiments. In the new era of multi-scale multi-physics computational based technology development, the experiments will still be needed but they will be performed at different scales to calibrate and validate models leading predictive simulations. Cost saving goals of programs will require us to minimize the required number of validation experiments. Utilization of more multi-scale multi-physics models introduces complexities in the validation of predictive tools. Traditional methodologies will have to be modified to address these arising issues. This paper lays out the basic aspects of a methodology that can be potentially used to address these new challenges in design and licensing of evolving nuclear technology programs. The main components of the proposed methodology are verification, validation, calibration, and uncertainty quantification. An enhanced calibration concept is introduced and is accomplished through data assimilation. The goal is to enable best-estimate prediction of system behaviors in both normal and safety related environments. To achieve this goal requires the additional steps of estimating the domain of validation and quantification of uncertainties that allow for extension of results to areas of the validation domain that are not directly tested with experiments, which might include extension of the modeling and simulation (M and S) capabilities for application to full-scale systems. The new methodology suggests a formalism to quantify an adequate level of validation (predictive maturity) with respect to required selective data so that required testing can be minimized for

  5. Improved best estimate plus uncertainty methodology including advanced validation concepts to license evolving nuclear reactors

    Energy Technology Data Exchange (ETDEWEB)

    Unal, Cetin [Los Alamos National Laboratory; Williams, Brian [Los Alamos National Laboratory; Mc Clure, Patrick [Los Alamos National Laboratory; Nelson, Ralph A [IDAHO NATIONAL LAB

    2010-01-01

    Many evolving nuclear energy programs plan to use advanced predictive multi-scale multi-physics simulation and modeling capabilities to reduce cost and time from design through licensing. Historically, the role of experiments was primary tool for design and understanding of nuclear system behavior while modeling and simulation played the subordinate role of supporting experiments. In the new era of multi-scale multi-physics computational based technology development, the experiments will still be needed but they will be performed at different scales to calibrate and validate models leading predictive simulations. Cost saving goals of programs will require us to minimize the required number of validation experiments. Utilization of more multi-scale multi-physics models introduces complexities in the validation of predictive tools. Traditional methodologies will have to be modified to address these arising issues. This paper lays out the basic aspects of a methodology that can be potentially used to address these new challenges in design and licensing of evolving nuclear technology programs. The main components of the proposed methodology are verification, validation, calibration, and uncertainty quantification. An enhanced calibration concept is introduced and is accomplished through data assimilation. The goal is to enable best-estimate prediction of system behaviors in both normal and safety related environments. To achieve this goal requires the additional steps of estimating the domain of validation and quantification of uncertainties that allow for extension of results to areas of the validation domain that are not directly tested with experiments, which might include extension of the modeling and simulation (M&S) capabilities for application to full-scale systems. The new methodology suggests a formalism to quantify an adequate level of validation (predictive maturity) with respect to required selective data so that required testing can be minimized for cost

  6. Evolving Concepts in the Pathogenesis of NASH: Beyond Steatosis and Inflammation

    Directory of Open Access Journals (Sweden)

    William Peverill

    2014-05-01

    Full Text Available Non-alcoholic steatohepatitis (NASH is characterised by hepatic steatosis and inflammation and, in some patients, progressive fibrosis leading to cirrhosis. An understanding of the pathogenesis of NASH is still evolving but current evidence suggests multiple metabolic factors critically disrupt homeostasis and induce an inflammatory cascade and ensuing fibrosis. The mechanisms underlying these changes and the complex inter-cellular interactions that mediate fibrogenesis are yet to be fully elucidated. Lipotoxicity, in the setting of excess free fatty acids, obesity, and insulin resistance, appears to be the central driver of cellular injury via oxidative stress. Hepatocyte apoptosis and/or senescence contribute to activation of the inflammasome via a variety of intra- and inter-cellular signalling mechanisms leading to fibrosis. Current evidence suggests that periportal components, including the ductular reaction and expansion of the hepatic progenitor cell compartment, may be involved and that the Th17 response may mediate disease progression. This review aims to provide an overview of the pathogenesis of NASH and summarises the evidence pertaining to key mechanisms implicated in the transition from steatosis and inflammation to fibrosis. Currently there are limited treatments for NASH although an increasing understanding of its pathogenesis will likely improve the development and use of interventions in the future.

  7. Stem cells and the evolving notion of cellular identity

    OpenAIRE

    Daley, George Q.

    2015-01-01

    Stem cells are but one class of the myriad types of cells within an organism. With potential to self-renew and capacity to differentiate, stem cells play essential roles at multiple stages of development. In the early embryo, pluripotent stem cells represent progenitors for all tissues while later in development, tissue-restricted stem cells give rise to cells with highly specialized functions. As best understood in the blood, skin and gut, stem cells are the seeds that sustain tissue homeost...

  8. Improved best estimate plus uncertainty methodology, including advanced validation concepts, to license evolving nuclear reactors

    International Nuclear Information System (INIS)

    Unal, C.; Williams, B.; Hemez, F.; Atamturktur, S.H.; McClure, P.

    2011-01-01

    the design and licensing of evolving nuclear technology. The main components of the proposed methodology are verification, validation, calibration, and uncertainty quantification - steps similar to the components of the traditional US Nuclear Regulatory Commission (NRC) licensing approach, with the exception of the calibration step. An enhanced calibration concept is introduced here, and is accomplished through data assimilation. The goal of this methodology is to enable best-estimate prediction of system behaviors in both normal and safety-related environments. This goal requires the additional steps of estimating the domain of validation, and quantification of uncertainties, allowing for the extension of results to areas of the validation domain that are not directly tested with experiments. These might include the extension of the M and S capabilities for application to full-scale systems. The new methodology suggests a formalism to quantify an adequate level of validation (predictive maturity) with respect to existing data, so that required new testing can be minimized, saving cost by demonstrating that further testing will not enhance the quality of the predictive tools. The proposed methodology is at a conceptual level. Upon maturity, and if considered favorably by the stakeholders, it could serve as a new framework for the next generation of the best estimate plus uncertainty (BEPU) licensing methodology that the NRC has developed. In order to achieve maturity, the methodology must be communicated to scientific, design, and regulatory stakeholders for discussion and debate. This paper is the first step in establishing that communication.

  9. Evolving Hematopoietic Stem Cell Transplantation Strategies in Severe Aplastic Anemia

    Science.gov (United States)

    Dietz, Andrew C.; Lucchini, Giovanna; Samarasinghe, Sujith; Pulsipher, Michael A.

    2016-01-01

    Purpose of Review Significant improvements in unrelated donor hematopoietic stem cell transplantation (HSCT) in recent years has solidified its therapeutic role in severe aplastic anemia (SAA) and led to evolution of treatment algorithms, particularly for children. Recent Findings Advances in understanding genetics of inherited bone marrow failure syndromes (IBMFS) have allowed more confidence in accurately diagnosing SAA and avoiding treatments that could be dangerous and ineffective in individuals with IBMFS, which can be diagnosed in 10–20% of children presenting with a picture of SAA. Additionally long-term survival after matched sibling donor (MSD) and matched unrelated donor (MUD) HSCT now exceed 90% in children. Late effects after HSCT for SAA are minimal with current strategies and compare favorably to late effects after up-front immunosuppressive therapy (IST), except for patients with chronic graft versus host disease (GVHD). Summary 1) Careful assessment for signs or symptoms of IBMFS along with genetic screening for these disorders is of major importance. 2) MSD HSCT is already considered standard of care for up-front therapy and some groups are evaluating MUD HSCT as primary therapy. 3) Ongoing studies will continue to challenge treatment algorithms and may lead to an even more expanded role for HSCT in SAA. PMID:26626557

  10. The evolving concept of "patient-centeredness" in patient-physician communication research.

    Science.gov (United States)

    Ishikawa, Hirono; Hashimoto, Hideki; Kiuchi, Takahiro

    2013-11-01

    Over the past few decades, the concept of "patient-centeredness" has been intensively studied in health communication research on patient-physician interaction. Despite its popularity, this concept has often been criticized for lacking a unified definition and operationalized measurement. This article reviews how health communication research on patient-physician interaction has conceptualized and operationalized patient-centered communication based on four major theoretical perspectives in sociology (i.e., functionalism, conflict theory, utilitarianism, and social constructionism), and discusses the agenda for future research in this field. Each theory addresses different aspects of the patient-physician relationship and communication from different theoretical viewpoints. Patient-centeredness is a multifaceted construct with no single theory that can sufficiently define the whole concept. Different theoretical perspectives of patient-centered communication can be selectively adopted according to the context and nature of problems in the patient-physician relationship that a particular study aims to explore. The present study may provide a useful framework: it offers an overview of the differing models of patient-centered communication and the expected roles and goals in each model; it does so toward identifying a communication model that fits the patient and the context and toward theoretically reconstructing existing measures of patient-centered communication. Furthermore, although patient-centered communication has been defined mainly from the viewpoint of physician's behaviors aimed at achieving patient-centered care, patient competence is also required for patient-centered communication. This needs to be examined in current medical practice. Copyright © 2013 Elsevier Ltd. All rights reserved.

  11. The emergence of psychiatric semiology during the Age of Revolution: evolving concepts of 'normal' and 'pathological'.

    Science.gov (United States)

    Londoño, Diego Enrique; Dening, Tom

    2016-06-01

    This article addresses some important questions in psychiatric semiology. The concept of a sign is crucial in psychiatry. How do signs emerge, and what gives them validity and legitimacy? What are the boundaries of 'normal' and 'pathological' behaviour and mental experiences? To address these issues, we analyse the characteristics and rules that govern semiological signs and clinical elements. We examine 'normality' from the perspective of Georges Canguilehm and compare the differences of 'normal' in physiology and psychiatry. We then examine the history and the philosophical, linguistic and medical-psychiatric origins of semiology during the eighteenth and nineteenth centuries (the Age of Revolution). The field of rhetoric and oratory has emphasized the importance of passions, emotions and language as applied to signs of madness. Another perspective on semiology, provided by Michel Foucault, lays stress on the concept of 'instinct' and the axis of voluntary-involuntary behaviour. Finally, we analyse how statistics and eugenics have played an important role in our current conceptualization of the norm and therefore the scientific discourse behind the established clinical signs. © The Author(s) 2016.

  12. Stem cells: Concepts and prospects

    Indian Academy of Sciences (India)

    development exemplified by murine experiments motivated the ... from specific regions of the brain, cardiac stem cells from atrial ..... have also been shown to integrate and differentiate .... to vascular network structures in three dimensional.

  13. Hairy cell leukemia: current concepts.

    Science.gov (United States)

    Cannon, Timothy; Mobarek, Dalia; Wegge, Julia; Tabbara, Imad A

    2008-10-01

    Hairy cell Leukemia (HCL) is a chronic lymphoproliferative disorder that was characterized in the late 1950s. HCL is defined, according to the WHO classification, as a mature (peripheral) B-cell neoplasm (1). HCL accounts for between 2-3% of all leukemia cases, with about 600 new cases diagnosed in the U.S. each year (1). HCL occurs more commonly in males, with an overall male to female ratio of approximately 4:1. The median age of onset is 52 years. This disease is seen more commonly in Caucasians and appears to be especially frequent in Ashkenazi Jewish males, with rare occurrence in persons of Asian and African descents (1). Hairy cells are distinct, clonal B cells arrested at a late stage of maturation. They are small B lymphoid cells that possess oval nuclei and abundant cytoplasm with characteristic micro-filamentous ("hairy") projections. They strongly express CD103, CD22, and CD11c (2). These cells typically infiltrate the bone marrow, the spleen, and to a lesser extent the liver, lymph nodes, and skin. Many patients present with splenomegaly and pancytopenia. Other clinical manifestations include recurrent opportunistic infections and vasculitis. Historically, HCL was considered uniformly fatal (2). However, recent treatment advances, using purine analogues such as Cladribine and Pentostatin, led to a significant improvement in prognosis with achievement of high response rates and durable remissions (2).

  14. Pediatric Autoimmune Neuropsychiatric Disorders Associated with Streptococcal Infections (PANDAS: An Evolving Concept

    Directory of Open Access Journals (Sweden)

    Antonella Macerollo

    2013-09-01

    Full Text Available Pediatric autoimmune neuropsychiatric disorders associated with streptococcus infections (PANDAS originated from the observational work of Swedo and collaborators, who formalized their definition in 1998 in a set of operational criteria. The application of these criteria, which focuses on tics and obsessive-compulsive symptoms as core symptoms, has encountered difficulties, eventually leading to a high rate of misdiagnosis. In particular, the core feature represented by the association between newly diagnosed infections and neuropsychiatric symptom relapses in youths with this diagnosis could not be demonstrated by longitudinal studies. Exploratory studies aiming to identify clinical or cognitive features that could discriminate PANDAS from other pediatric obsessive-compulsive and tic disorders present methodological limitations, and therefore are not conclusive. Other behavioral features, in addition to obsessive-compulsive symptoms and tics, have been included in pediatric acute-onset neuropsychiatric syndromes (PANS and childhood acute neuropsychiatric syndromes (CANS, two new concepts recently proposed in order to define a much broader clinical spectrum encompassing etiologically diverse entities. Given the uncertainties on the clinical definition of PANDAS, it is not surprising that evidence in support of a post-infectious, immune-mediated pathophysiology is also insufficient. Anti-dopamine receptor antibodies might be relevant to both Sydenham’s chorea (SC—the prototypical post-streptococcal neuropsychiatric disorder—and some rare forms of encephalitis targeting the basal ganglia specifically, but studies exploring their association with children fulfilling Swedo’s criteria for PANDAS have been inconclusive. Moreover, we lack evidence in favor of the efficacy of antibiotic prophylaxis or tonsillectomy in patients fulfilling Swedo’s criteria for PANDAS, whereas a response to immune-mediated treatments like intravenous

  15. System design in an evolving system-of-systems architecture and concept of operations

    Science.gov (United States)

    Rovekamp, Roger N., Jr.

    Proposals for space exploration architectures have increased in complexity and scope. Constituent systems (e.g., rovers, habitats, in-situ resource utilization facilities, transfer vehicles, etc) must meet the needs of these architectures by performing in multiple operational environments and across multiple phases of the architecture's evolution. This thesis proposes an approach for using system-of-systems engineering principles in conjunction with system design methods (e.g., Multi-objective optimization, genetic algorithms, etc) to create system design options that perform effectively at both the system and system-of-systems levels, across multiple concepts of operations, and over multiple architectural phases. The framework is presented by way of an application problem that investigates the design of power systems within a power sharing architecture for use in a human Lunar Surface Exploration Campaign. A computer model has been developed that uses candidate power grid distribution solutions for a notional lunar base. The agent-based model utilizes virtual control agents to manage the interactions of various exploration and infrastructure agents. The philosophy behind the model is based both on lunar power supply strategies proposed in literature, as well as on the author's own approaches for power distribution strategies of future lunar bases. In addition to proposing a framework for system design, further implications of system-of-systems engineering principles are briefly explored, specifically as they relate to producing more robust cross-cultural system-of-systems architecture solutions.

  16. Challenges for fuel cells as stationary power resource in the evolving energy enterprise

    Science.gov (United States)

    Rastler, Dan

    The primary market challenges for fuel cells as stationary power resources in evolving energy markets are reviewed. Fuel cell power systems have significant barriers to overcome in their anticipated role as decentralized energy power systems. Market segments for fuel cells include combined heat and power; low-cost energy, premium power; peak shaving; and load management and grid support. Understanding the role and fit of fuel cell systems in evolving energy markets and the highest value applications are a major challenge for developers and government funding organizations. The most likely adopters of fuel cell systems and the challenges facing each adopter in the target market segment are reviewed. Adopters include generation companies, utility distribution companies, retail energy service providers and end-users. Key challenges include: overcoming technology risk; achieving retail competitiveness; understanding high value markets and end-user needs; distribution and service channels; regulatory policy issues; and the integration of these decentralized resources within the electrical distribution system.

  17. Tumorigenic Heterogeneity in Cancer Stem Cells Evolved from Long-term Cultures of Telomerase-Immortalized

    DEFF Research Database (Denmark)

    Burns, Jorge S; Abdallah, Basem M; Guldberg, Per

    2005-01-01

    Long-term cultures of telomerase-transduced adult human mesenchymal stem cells (hMSC) may evolve spontaneous genetic changes leading to tumorigenicity in immunodeficient mice (e.g., hMSC-TERT20). We wished to clarify whether this unusual phenotype reflected a rare but dominant subpopulation or if...

  18. Type 2 diabetes: epidemiologic trends, evolving pathogenetic [corrected] concepts, and recent changes in therapeutic approach.

    Science.gov (United States)

    Rizvi, Ali A

    2004-11-01

    The prevalence of type 2 diabetes has assumed epidemic dimensions. Children are now vulnerable to a disease that was once the exclusive domain of adulthood. Increased body weight and sedentary behavior accelerate insulin resistance and beta-cell dysfunction, leading to the clinical manifestation of hyperglycemia. Other cardiovascular risk factors tend to cluster in this milieu, setting the stage for vastly increased macrovascular morbidity. Many more people have impaired glucose tolerance ('prediabetes'). They are not only at risk for frank diabetes but also for the recently recognized entity of 'metabolic syndrome,' which is further characterized by hypertension, dyslipidemia, and central adiposity. A multifactorial approach addressing these aspects in addition to intensive glycemic control is the most efficacious therapy, optimally achieved through a team effort comprising the clinician, diabetes nurse, dietitian, and other professionals. Early use of oral-agent combinations is gaining favor. Insulin is best utilized in a basal-bolus fashion to manage both fasting and postprandial glycemia, delivered with multiple-dose injections or continuously via the pump. In hospitalized patients, good diabetic control reduces mortality. Finally, recent trials show that optimal weight maintenance and regular exercise can prevent or delay type 2 diabetes. Such information can serve as the foundation for large-scale preventive endeavors at the community level.

  19. Evolving concepts of diagnosis, pathogenesis, and therapy of Sjögren's syndrome.

    Science.gov (United States)

    Fox, R I; Törnwall, J; Maruyama, T; Stern, M

    1998-09-01

    Differences in diagnostic criteria for Sjögren's Syndrome (SS) have led to confusion in the research literature and in clinical practice. A particular challenge is the clinical diagnosis of the patients with sicca symptoms, fibromyalgia, chronic fatigue, vague cognitive defects, and a low titer antinuclear antibody. Until recently, many of these patients would have been classified as primary SS using the European criteria. A suggested revision of the European criteria will require inclusion of anti SS-A antibody or characteristic minor salivary gland biopsy, leading to greater agreement between European and San Diego criteria. Recent studies have emphasized that lacrimal and salivary gland flow involves an entire "functional" unit that includes the mucosal surface (the site of inflammation), efferent nerve signals sent to the midbrain (lacrimatory and salvatory nucleus), efferent neural signals from the brain, and acinal/ductal structures in the gland. Thus, symptoms of dryness or pain can result from interferences with any part of this functional unit. The initiating antigens in SS remain unknown, but immune reactivity against SS-A, SS-B, fodrin, alpha- amylase, and carbonic anhydrase have been demonstrated in patients with established disease. The inflammatory process in the gland releases metalloproteinases that alter the relationship of epithelial cells to their matrix, an interaction that is necessary for glandular function and survival. Therapies for SS remain inadequate. In SS patients with immune-mediated extraglandular manifestation (ie, lung, kidney, skin, nerve), the therapeutic approach is similar to systemic lupus erythematosus, although these therapies have relatively little effect on tear or saliva flow.

  20. Multi-Capacity Load Cell Concept

    Directory of Open Access Journals (Sweden)

    Seif. M. OSMAN

    2014-09-01

    Full Text Available Force measuring systems are usually used to calibrate force generated systems, it is not preferable to use load cells to measure forces less than 10 % of its nominal capacity. Several load cells are required to offer calibration facilities at sites to cover different ranges, this lead to difficulties in handling procedures, through the need for several carrying cases to carry this overweight in addition to the over cost of purchasing several load cells. This article concerns with introducing a new concept for designing a multi-capacity load cell as a new force standard in the field of measuring the force. This multi-capacity load cell will replace a set of load cells and reflects economically on the total cost and on easiness of handling procedures.

  1. Valve Concepts for Microfluidic Cell Handling

    Directory of Open Access Journals (Sweden)

    M. Grabowski

    2010-01-01

    Full Text Available In this paper we present various pneumatically actuated microfluidic valves to enable user-defined fluid management within a microfluidic chip. To identify a feasible valve design, certain valve concepts are simulated in ANSYS to investigate the pressure dependent opening and closing characteristics of each design. The results are verified in a series of tests. Both the microfluidic layer and the pneumatic layer are realized by means of soft-lithographic techniques. In this way, a network of channels is fabricated in photoresist as a molding master. By casting these masters with PDMS (polydimethylsiloxane we get polymeric replicas containing the channel network. After a plasma-enhanced bonding process, the two layers are irreversibly bonded to each other. The bonding is tight for pressures up to 2 bar. The valves are integrated into a microfluidic cell handling system that is designed to manipulate cells in the presence of a liquid reagent (e.g. PEG – polyethylene glycol, for cell fusion. For this purpose a user-defined fluid management system is developed. The first test series with human cell lines show that the microfluidic chip is suitable for accumulating cells within a reaction chamber, where they can be flushed by a liquid medium.

  2. Precision toxicology based on single cell sequencing: an evolving trend in toxicological evaluations and mechanism exploration.

    Science.gov (United States)

    Zhang, Boyang; Huang, Kunlun; Zhu, Liye; Luo, Yunbo; Xu, Wentao

    2017-07-01

    In this review, we introduce a new concept, precision toxicology: the mode of action of chemical- or drug-induced toxicity can be sensitively and specifically investigated by isolating a small group of cells or even a single cell with typical phenotype of interest followed by a single cell sequencing-based analysis. Precision toxicology can contribute to the better detection of subtle intracellular changes in response to exogenous substrates, and thus help researchers find solutions to control or relieve the toxicological effects that are serious threats to human health. We give examples for single cell isolation and recommend laser capture microdissection for in vivo studies and flow cytometric sorting for in vitro studies. In addition, we introduce the procedures for single cell sequencing and describe the expected application of these techniques to toxicological evaluations and mechanism exploration, which we believe will become a trend in toxicology.

  3. Use of the parameterised finite element method to robustly and efficiently evolve the edge of a moving cell.

    Science.gov (United States)

    Neilson, Matthew P; Mackenzie, John A; Webb, Steven D; Insall, Robert H

    2010-11-01

    In this paper we present a computational tool that enables the simulation of mathematical models of cell migration and chemotaxis on an evolving cell membrane. Recent models require the numerical solution of systems of reaction-diffusion equations on the evolving cell membrane and then the solution state is used to drive the evolution of the cell edge. Previous work involved moving the cell edge using a level set method (LSM). However, the LSM is computationally very expensive, which severely limits the practical usefulness of the algorithm. To address this issue, we have employed the parameterised finite element method (PFEM) as an alternative method for evolving a cell boundary. We show that the PFEM is far more efficient and robust than the LSM. We therefore suggest that the PFEM potentially has an essential role to play in computational modelling efforts towards the understanding of many of the complex issues related to chemotaxis.

  4. Renal cell carcinoma: evolving approaches to advanced non-clear cell carcinoma

    Directory of Open Access Journals (Sweden)

    Daniel Y.C. Heng

    2011-12-01

    Full Text Available The treatment of metastatic renal cell carcinoma (RCC has changed dramatically with the introduction of targeted therapies including sunitinib, sorafenib, and temsirolimus. Because patients with conventional clear cell histology account for 75- 80% of all patients with RCC, there has been little accumulated evidence on the treatment of patients with non-clear cell histologies. Most clinical trials have excluded them from enrolment, except for randomized studies investigating temsirolimus. Many retrospective studies on the use of all three of these targeted therapies in patients with non-clear cell histology have demonstrated response rates ranging from 3.7%–16%. Although response rates may not be as high compared to patients with clear cell histologies, targeted therapy does provide a clinically meaningful response.

  5. The Ever-Evolving Concept of the Gene: The Use of RNA/Protein Experimental Techniques to Understand Genome Functions

    Directory of Open Access Journals (Sweden)

    Andrea Cipriano

    2018-03-01

    Full Text Available The completion of the human genome sequence together with advances in sequencing technologies have shifted the paradigm of the genome, as composed of discrete and hereditable coding entities, and have shown the abundance of functional noncoding DNA. This part of the genome, previously dismissed as “junk” DNA, increases proportionally with organismal complexity and contributes to gene regulation beyond the boundaries of known protein-coding genes. Different classes of functionally relevant nonprotein-coding RNAs are transcribed from noncoding DNA sequences. Among them are the long noncoding RNAs (lncRNAs, which are thought to participate in the basal regulation of protein-coding genes at both transcriptional and post-transcriptional levels. Although knowledge of this field is still limited, the ability of lncRNAs to localize in different cellular compartments, to fold into specific secondary structures and to interact with different molecules (RNA or proteins endows them with multiple regulatory mechanisms. It is becoming evident that lncRNAs may play a crucial role in most biological processes such as the control of development, differentiation and cell growth. This review places the evolution of the concept of the gene in its historical context, from Darwin's hypothetical mechanism of heredity to the post-genomic era. We discuss how the original idea of protein-coding genes as unique determinants of phenotypic traits has been reconsidered in light of the existence of noncoding RNAs. We summarize the technological developments which have been made in the genome-wide identification and study of lncRNAs and emphasize the methodologies that have aided our understanding of the complexity of lncRNA-protein interactions in recent years.

  6. Re-defining the concepts of waste and waste management:evolving the Theory of Waste Management

    OpenAIRE

    Pongrácz, E. (Eva)

    2002-01-01

    Abstract In an attempt to construct a new agenda for waste management, this thesis explores the importance of the definition of waste and its impact on waste management, and the role of ownership in waste management. It is recognised that present legal waste definitions are ambiguous and do not really give an insight into the concept of waste. Moreover, despite its explicit wish of waste prevention, when according to present legislation a thing is assigned the label...

  7. STEM CELL RESEARCH-CONCEPT AND CONTROVERSIES

    African Journals Online (AJOL)

    Dr. E. P. Gharoro

    cells, heart cells, brain cells, etc.). Some researchers regard them as offering the greatest potential for the .... anaemia, heart damage, corneal damage, etc. To be useful for transplant purposes, stem cells must ... activity in the brain was demonstrated contradicting caja's “no new neurons” dogma. However, research into.

  8. Unconventional device concepts for polymer solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Veenstra, S.C.; Slooff, L.H.; Verhees, W.J.H.; Cobussen-Pool, E.M.; Lenzmann, F.O.; Kroon, J.M. [ECN Solar Energy, Petten (Netherlands); Sessolo, M.; Bolink, H.J. [Instituto de Ciencia Molecular, Universidad de Valencia, Valencia (Spain)

    2009-09-15

    The inclusion of metal-oxide layers in polymer solar cells enables the fabrication of a series of unconventional device architectures. These devices include: semi-transparent polymer solar cells, devices with inverted polarity, as well as devices with air stable electrodes. A proof-of-principle of these devices is presented. The anticipated benefits of these novel device structures over conventional polymer solar cells are discussed.

  9. REM Sleep Behavior Disorder: Updated Review of the Core Features, the RBD-Neurodegenerative Disease Association, Evolving Concepts, Controversies, and Future Directions

    Science.gov (United States)

    Boeve, Bradley F.

    2010-01-01

    Rapid eye movement (REM) sleep behavior disorder (RBD) is a parasomnia manifested by vivid, often frightening dreams associated with simple or complex motor behavior during REM sleep. Patients appear to “act out their dreams,” in which the exhibited behaviors mirror the content of the dreams, and the dream content often involves a chasing or attacking theme. The polysomnographic features of RBD include increased electromyographic tone +/- dream enactment behavior during REM sleep. Management with counseling and pharmacologic measures is usually straight-forward and effective. In this review, the terminology, clinical and polysomnographic features, demographic and epidemiologic features, diagnostic criteria, differential diagnosis, and management strategies are discussed. Recent data on the suspected pathophysiologic mechanisms of RBD are also reviewed. The literature and our institutional experience on RBD are next discussed, with an emphasis on the RBD-neurodegenerative disease association and particularly the RBD-synucleinopathy association. Several issues relating to evolving concepts, controversies, and future directions are then reviewed, with an emphasis on idiopathic RBD representing an early feature of a neurodegenerative disease and particularly an evolving synucleinopathy. Planning for future therapies that impact patients with idiopathic RBD is reviewed in detail. PMID:20146689

  10. New physical concepts for cell amoeboid motion.

    Science.gov (United States)

    Evans, E

    1993-04-01

    Amoeboid motion of cells is an essential mechanism in the function of many biological organisms (e.g., the regiment of scavenger cells in the immune defense system of animals). This process involves rapid chemical polymerization (with numerous protein constituents) to create a musclelike contractile network that advances the cell over the surface. Significant progress has been made in the biology and biochemistry of motile cells, but the physical dynamics of cell spreading and contraction are not well understood. The reason is that general approaches are formulated from complex mass, momentum, and chemical reaction equations for multiphase-multicomponent flow with the nontrivial difficulty of moving boundaries. However, there are strong clues to the dynamics that allow bold steps to be taken in simplifying the physics of motion. First, amoeboid cells often exhibit exceptional kinematics, i.e., steady advance and retraction of local fixed-shape patterns. Second, recent evidence has shown that cell projections "grow" by polymerization along the advancing boundary of the cell. Together, these characteristics represent a local growth process pinned to the interfacial contour of a contractile network. As such, the moving boundary becomes tractable, but subtle features of the motion lead to specific requirements for the chemical nature of the boundary polymerization process. To demonstrate these features, simple examples for limiting conditions of substrate interaction (i.e., "strong" and "weak" adhesion) are compared with data from experimental studies of yeast particle engulfment by blood granulocytes and actin network dynamics in fishscale keratocytes.

  11. Microbial Heat Recovery Cell (MHRC) System Concept

    Energy Technology Data Exchange (ETDEWEB)

    None

    2017-09-01

    This factsheet describes a project that aimed to develop a microbial heat recovery cell (MHRC) system that combines a microbial reverse electrodialysis technology with waste heat recovery to convert industrial effluents into electricity and hydrogen.

  12. Evolving T-cell vaccine strategies for HIV, the virus with a thousand faces

    Energy Technology Data Exchange (ETDEWEB)

    Korber, Bette [Los Alamos National Laboratory

    2009-01-01

    HIV's rapid global spread and the human suffering it has left in its wake have made AIDS a global heath priority for the 25 years since its discovery. Yet its capacity to rapidly evolve has made combating this virus a tremendous challenge. The obstacles to creating an effective HIV vaccine are formidable, but there are advances in the field on many fronts, in terms of novel vectors, adjuvants, and antigen design strategies. SIV live attenuated vaccine models are able to confer protection against heterologous challenge, and this continues to provide opportunities to explore the biological underpinnings of a protective effect (9). More indirect, but equally important, is new understanding regarding the biology of acute infection (43), the role of immune response in long-term non-progression (6,62, 81), and defining characteristics of broadly neutralizing antibodies (4). In this review we will focus on summarizing strategies directed towards a single issue, that of contending with HIV variation in terms of designing aT-cell vaccine. The strategies that prove most effective in this area can ultimately be combined with the best strategies under development in other areas, with the hope of ultimately converging on a viable vaccine candidate. Only two large HIV vaccine efficacy trials have been completed and both have failed to prevent infection or confer a benefit to infected individual (23,34), but there is ample reason to continue our efforts. A historic breakthrough came in 1996, when it was realized that although the virus could escape from a single antiretroviral (ARV) therapy, it could be thwarted by a combination of medications that simultaneously targeted different parts of the virus (HAART) (38). This revelation came after 15 years of research, thought, and clinical testing; to enable that vital progress the research and clinical communities had to first define and understand, then develop a strategy to counter, the remarkable evolutionary potential of the

  13. Somatoparaphrenia: evolving theories and concepts.

    Science.gov (United States)

    Feinberg, Todd E; Venneri, Annalena

    2014-12-01

    Somatoparaphrenia, a syndrome that involves at a minimum unawareness of ownership of a body part, in addition involves productive features including delusional misidentification and confabulation. In this review we describe some of the clinical and neuroanatomical features of somatoparaphrenia highlighting its delusional and confabulatory aspects. Possible theoretical frameworks are reviewed taking into account cognitive, psychodynamic, and philosophical views. We suggest that future studies should approach this syndrome through investigations of structural and functional connectivity and focus on the possible interplay between alterations in major functional networks of the brain, such as the default mode and salience networks, but also take into account motivational variables. Copyright © 2014 Elsevier Ltd. All rights reserved.

  14. Coreless Concept for High Gradient Induction Cell

    International Nuclear Information System (INIS)

    Krasnykh, Anatoly

    2008-01-01

    An induction linac cell for a high gradient is discussed. The proposed solid state coreless approach for the induction linac topology (SLIM(reg s ign)) is based on nanosecond mode operation. This mode may have an acceleration gradient comparable with gradients of rf- accelerator structures. The discussed induction system has the high electric efficiency. The key elements are a solid state semiconductor switch and a high electric density dielectric with a thin section length. The energy in the induction system is storied in the magnetic field. The nanosecond current break-up produces the high voltage. The induced voltage is used for acceleration. This manner of an operation allows the use of low voltage elements in the booster part and achieves a high accelerating gradient. The proposed topology was tested in POP (proof of principle) experiments

  15. Bio optofluidics cell sorter: cell-BOCS concept and applications

    Science.gov (United States)

    Roth, Tue; Glückstad, Jesper

    2012-03-01

    The cell-BOCS is a novel microfluidics based cell-sorting instrument utilizing next generation optical trapping technology developed at the Technical University of Denmark. It is targeted emerging bio-medical research and diagnostics markets where it for certain applications offers a number of advantages over conventional fluorescence activated cell-sorting (FACSTM) technology. Advantages include gentle handling of cells, sterile sorting, easy operation, small footprint and lower cost allowing out-of-core-facility use. Application examples are found within sorting of fragile transfected cells, high value samples and primary cell lines, where traditional FACS technology has limited application due to it's droplet-based approach to cell-sorting. In the diagnostics field, in particular applying the cell-BOCS for isolating pure populations of circulating tumor cells is an area that has generated a lot of interest.

  16. Modelling of multiple short-length-scale stall cells in an axial compressor using evolved GMDH neural networks

    International Nuclear Information System (INIS)

    Amanifard, N.; Nariman-Zadeh, N.; Farahani, M.H.; Khalkhali, A.

    2008-01-01

    Over the past 15 years there have been several research efforts to capture the stall inception nature in axial flow compressors. However previous analytical models could not explain the formation of short-length-scale stall cells. This paper provides a new model based on evolved GMDH neural network for transient evolution of multiple short-length-scale stall cells in an axial compressor. Genetic Algorithms (GAs) are also employed for optimal design of connectivity configuration of such GMDH-type neural networks. In this way, low-pass filter (LPF) pressure trace near the rotor leading edge is modelled with respect to the variation of pressure coefficient, flow rate coefficient, and number of rotor rotations which are defined as inputs

  17. DNA aptamer evolved by cell-SELEX for recognition of prostate cancer.

    Directory of Open Access Journals (Sweden)

    Yuanyuan Wang

    Full Text Available Morbidity and mortality of prostate cancer (PCa have increased in recent years worldwide. Currently existing methods for diagnosis and treatment do not make the situation improve, especially for hormone refractory prostate cancer (HRPC. The lack of molecular probes for PCa hindered the early diagnosis of metastasis and accurate staging for PCa. In this work, we have developed a new aptamer probe Wy-5a against PCa cell line PC-3 by cell-SELEX technique. Wy-5a shows high specificity to the target cells with dissociation constants in the nanomolar range, and does not recognize other tested PCa cell lines and other tested tumor cell lines. The staining of clinical tissue sections with fluorescent dye labeled Wy-5a shows that sections from high risk group with metastasis exhibited stronger fluorescence and sections from Benign Prostatic Hyperplasia (BPH did not exhibit notable fluorescence, which suggests that aptamer Wy-5a may bind to protein related to the progression of PCa. The high affinity and specificity of Wy-5a makes this aptamer hold potential for application in diagnosis and target therapy of PCa.

  18. Fatal Metastatic Cutaneous Squamous Cell Carcinoma Evolving from a Localized Verrucous Epidermal Nevus

    Directory of Open Access Journals (Sweden)

    Hassan Riad

    2013-10-01

    Full Text Available A malignant transformation is known to occur in many nevi such as a sebaceous nevus or a basal cell nevus, but a verrucous epidermal nevus has only rarely been associated with neoplastic changes. Keratoacanthoma, multifocal papillary apocrine adenoma, multiple malignant eccrine poroma, basal cell carcinoma and cutaneous squamous cell carcinoma (CSCC have all been reported to develop from a verrucous epidermal nevus. CSCC has also been reported to arise from other nevoid lesions like a nevus comedonicus, porokeratosis, a sebaceous nevus, an oral sponge nevus and an ichthyosiform nevus with CHILD syndrome. Here we report a case of progressive poorly differentiated CSCC arising from a localized verrucous epidermal nevus, which caused both spinal cord and brain metastasis.

  19. College Students' Conceptions of Stem Cells, Stem Cell Research, and Cloning

    Science.gov (United States)

    Concannon, James P.; Siegel, Marcelle A.; Halverson, Kristy; Freyermuth, Sharyn

    2010-01-01

    In this study, we examined 96 undergraduate non-science majors' conceptions of stem cells, stem cell research, and cloning. This study was performed at a large, Midwest, research extensive university. Participants in the study were asked to answer 23 questions relating to stem cells, stem cell research, and cloning in an on-line assessment before…

  20. The Evolving Landscape of Neurotoxicity by Unconjugated Bilirubin: Role of Glial Cells and Inflammation

    Directory of Open Access Journals (Sweden)

    Dora eBrites

    2012-05-01

    Full Text Available Unconjugated hyperbilirubinemia is a common condition in the first week of postnatal life. Although generally harmless, some neonates may develop very high levels of unconjugated bilirubin (UCB, which may surpass the protective mechanisms of the brain at preventing UCB accumulation. In this case, both short-term and long-term neurodevelopmental disabilities, such as acute and chronic UCB encephalopathy, known as kernicterus, or more subtle alterations designed as bilirubin-induced neurological dysfunction (BIND may be produced. There is a tremendous variability in babies’ vulnerability towards UCB for reasons not yet explained, but preterm birth, sepsis, hypoxia and haemolytic disease are comprised as risk factors. Therefore, UCB levels and neurological abnormalities are not strictly correlated. Even nowadays, the mechanisms of UCB neurotoxicity are still unclear, as are specific biomarkers, and little is known about lasting sequelae attributable to hyperbilirubinemia. On autopsy, UCB was shown to be within neurons, neuronal processes and microglia, and to produce loss of neurons, demyelination and gliosis. In isolated cell cultures, UCB was shown to impair neuronal arborization and to induce the release of proinflammatory cytokines from microglia and astrocytes. However, cell dependent-sensitivity to UCB toxicity and the role of each nerve cell type remain understood. This review provides a comprehensive insight into cell susceptibilities and molecular targets of UCB in neurons, astrocytes, and oligodendrocytes, and on phenotypic and functional responses of microglia to UCB. Interplay among glia elements and cross-talk with neurons, with a special emphasis in the UCB-induced immunostimulation, and the role of sepsis in BIND pathogenesis are highlighted. New and interesting data on the anti-inflammatory and antioxidant activities of different pharmacological agents are also presented, as novel and promising additional therapeutic approaches to

  1. Cell Surface Properties of Lactococcus lactis Reveal Milk Protein Binding Specifically Evolved in Dairy Isolates

    Directory of Open Access Journals (Sweden)

    Mariya Tarazanova

    2017-09-01

    Full Text Available Surface properties of bacteria are determined by the molecular composition of the cell wall and they are important for interactions of cells with their environment. Well-known examples of bacterial interactions with surfaces are biofilm formation and the fermentation of solid materials like food and feed. Lactococcus lactis is broadly used for the fermentation of cheese and buttermilk and it is primarily isolated from either plant material or the dairy environment. In this study, we characterized surface hydrophobicity, charge, emulsification properties, and the attachment to milk proteins of 55 L. lactis strains in stationary and exponential growth phases. The attachment to milk protein was assessed through a newly developed flow cytometry-based protocol. Besides finding a high degree of biodiversity, phenotype-genotype matching allowed the identification of candidate genes involved in the modification of the cell surface. Overexpression and gene deletion analysis allowed to verify the predictions for three identified proteins that altered surface hydrophobicity and attachment of milk proteins. The data also showed that lactococci isolated from a dairy environment bind higher amounts of milk proteins when compared to plant isolates. It remains to be determined whether the alteration of surface properties also has potential to alter starter culture functionalities.

  2. Cell Surface Properties of Lactococcus lactis Reveal Milk Protein Binding Specifically Evolved in Dairy Isolates

    Science.gov (United States)

    Tarazanova, Mariya; Huppertz, Thom; Beerthuyzen, Marke; van Schalkwijk, Saskia; Janssen, Patrick; Wels, Michiel; Kok, Jan; Bachmann, Herwig

    2017-01-01

    Surface properties of bacteria are determined by the molecular composition of the cell wall and they are important for interactions of cells with their environment. Well-known examples of bacterial interactions with surfaces are biofilm formation and the fermentation of solid materials like food and feed. Lactococcus lactis is broadly used for the fermentation of cheese and buttermilk and it is primarily isolated from either plant material or the dairy environment. In this study, we characterized surface hydrophobicity, charge, emulsification properties, and the attachment to milk proteins of 55 L. lactis strains in stationary and exponential growth phases. The attachment to milk protein was assessed through a newly developed flow cytometry-based protocol. Besides finding a high degree of biodiversity, phenotype-genotype matching allowed the identification of candidate genes involved in the modification of the cell surface. Overexpression and gene deletion analysis allowed to verify the predictions for three identified proteins that altered surface hydrophobicity and attachment of milk proteins. The data also showed that lactococci isolated from a dairy environment bind higher amounts of milk proteins when compared to plant isolates. It remains to be determined whether the alteration of surface properties also has potential to alter starter culture functionalities. PMID:28936202

  3. Cytokinesis-block micronucleus assay evolves into a 'cytome' assay of chromosomal instability, mitotic dysfunction and cell death

    International Nuclear Information System (INIS)

    Fenech, Michael

    2006-01-01

    The cytokinesis-block micronucleus (CBMN) assay was originally developed as an ideal system for measuring micronuclei (MNi) however it can also be used to measure nucleoplasmic bridges (NPBs), nuclear buds (NBUDs), cell death (necrosis or apoptosis) and nuclear division rate. Current evidence suggests that (a) NPBs originate from dicentric chromosomes in which the centromeres have been pulled to the opposite poles of the cell at anaphase and are therefore indicative of DNA mis-repair, chromosome rearrangement or telomere end-fusions, (b) NPBs may break to form MNi, (c) the nuclear budding process is the mechanism by which cells remove amplified and/or excess DNA and is therefore a marker of gene amplification and/or altered gene dosage, (d) cell cycle checkpoint defects result in micronucleus formation and (e) hypomethylation of DNA, induced nutritionally or by inhibition of DNA methyl transferase can lead to micronucleus formation either via chromosome loss or chromosome breakage. The strong correlation between micronucleus formation, nuclear budding and NPBs (r = 0.75-0.77, P < 0.001) induced by either folic acid deficiency or exposure to ionising radiation is supportive of the hypothesis that folic acid deficiency and/or ionising radiation cause genomic instability and gene amplification by the initiation of breakage-fusion-bridge cycles. In its comprehensive mode, the CBMN assay measures all cells including necrotic and apoptotic cells as well as number of nuclei per cell to provide a measure of cytotoxicity and mitotic activity. The CBMN assay has in fact evolved into a 'cytome' method for measuring comprehensively chromosomal instability phenotype and altered cellular viability caused by genetic defects and/or nutrional deficiencies and/or exogenous genotoxins thus opening up an exciting future for the use of this methodology in the emerging fields of nutrigenomics and toxicogenomics and their combinations

  4. Neoplastic stem cells: current concepts and clinical perspectives.

    Science.gov (United States)

    Schulenburg, Axel; Brämswig, Kira; Herrmann, Harald; Karlic, Heidrun; Mirkina, Irina; Hubmann, Rainer; Laffer, Sylvia; Marian, Brigitte; Shehata, Medhat; Krepler, Clemens; Pehamberger, Hubert; Grunt, Thomas; Jäger, Ulrich; Zielinski, Christoph C; Valent, Peter

    2010-11-01

    Neoplastic stem cells have initially been characterized in myeloid leukemias where NOD/SCID mouse-repopulating progenitors supposedly reside within a CD34+/Lin- subset of the malignant clone. These progenitors are considered to be self-renewing cells responsible for the in vivo long-term growth of neoplastic cells in leukemic patients. Therefore, these cells represent an attractive target of therapy. In some lymphoid leukemias, NOD/SCID mouse-repopulating cells were also reported to reside within the CD34+/Lin- subfraction of the clone. More recently, several attempts have been made to transfer the cancer stem cell concept to solid tumors and other non-hematopoietic neoplasms. In several of these tumors, the cell surface antigens AC133 (CD133) and CD44 are considered to indicate the potential of a cell to initiate permanent tumor formation in vivo. However, several questions concerning the phenotype, self-renewal capacity, stroma-dependence, and other properties of cancer- or leukemia-initiating cells remain to be solved. The current article provides a summary of our current knowledge on neoplastic (cancer) stem cells, with special emphasis on clinical implications and therapeutic options as well as a discussion about conceptual and technical limitations. Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.

  5. Myelodysplastic syndrome evolving from aplastic anemia treated with immunosuppressive therapy: efficacy of hematopoietic stem cell transplantation.

    Science.gov (United States)

    Kim, Sung-Yong; Le Rademacher, Jennifer; Antin, Joseph H; Anderlini, Paolo; Ayas, Mouhab; Battiwalla, Minoo; Carreras, Jeanette; Kurtzberg, Joanne; Nakamura, Ryotaro; Eapen, Mary; Deeg, H Joachim

    2014-12-01

    A proportion of patients with aplastic anemia who are treated with immunosuppressive therapy develop clonal hematologic disorders, including post-aplastic anemia myelodysplastic syndrome. Many will proceed to allogeneic hematopoietic stem cell transplantation. We identified 123 patients with post-aplastic anemia myelodysplastic syndrome who from 1991 through 2011 underwent allogeneic hematopoietic stem cell transplantation, and in a matched-pair analysis compared outcome to that in 393 patients with de novo myelodysplastic syndrome. There was no difference in overall survival. There were no significant differences with regard to 5-year probabilities of relapse, non-relapse mortality, relapse-free survival and overall survival; these were 14%, 40%, 46% and 49% for post-aplastic anemia myelodysplastic syndrome, and 20%, 33%, 47% and 49% for de novo myelodysplastic syndrome, respectively. In multivariate analysis, relapse (hazard ratio 0.71; P=0.18), non-relapse mortality (hazard ratio 1.28; P=0.18), relapse-free survival (hazard ratio 0.97; P=0.80) and overall survival (hazard ratio 1.02; P=0.88) of post-aplastic anemia myelodysplastic syndrome were similar to those of patients with de novo myelodysplastic syndrome. Cytogenetic risk was independently associated with overall survival in both groups. Thus, transplant success in patients with post-aplastic anemia myelodysplastic syndrome was similar to that in patients with de novo myelodysplastic syndrome, and cytogenetics was the only significant prognostic factor for post-aplastic anemia myelodysplastic syndrome patients. Copyright© Ferrata Storti Foundation.

  6. Strategic optimisation of microgrid by evolving a unitised regenerative fuel cell system operational criterion

    Science.gov (United States)

    Bhansali, Gaurav; Singh, Bhanu Pratap; Kumar, Rajesh

    2016-09-01

    In this paper, the problem of microgrid optimisation with storage has been addressed in an unaccounted way rather than confining it to loss minimisation. Unitised regenerative fuel cell (URFC) systems have been studied and employed in microgrids to store energy and feed it back into the system when required. A value function-dependent on line losses, URFC system operational cost and stored energy at the end of the day are defined here. The function is highly complex, nonlinear and multi dimensional in nature. Therefore, heuristic optimisation techniques in combination with load flow analysis are used here to resolve the network and time domain complexity related with the problem. Particle swarm optimisation with the forward/backward sweep algorithm ensures optimal operation of microgrid thereby minimising the operational cost of the microgrid. Results are shown and are found to be consistently improving with evolution of the solution strategy.

  7. Evolving radiological features of hypothalamo-pituitary lesions in adult patients with Langerhans cell histiocytosis (LCH)

    International Nuclear Information System (INIS)

    Makras, P.; Samara, C.; Antoniou, M.; Nikolakopoulou, Z.; Zetos, A.; Papadogias, D.; Piaditis, G.; Kaltsas, G.A.; Toloumis, G.; Andreakos, E.; Kontogeorgos, G.

    2006-01-01

    Langerhans cell histiocytosis (LCH) is a rare, systemic disease caused by monoclonal expansion of dendritic cells that shows a particular predilection for the hypothalamic-pituitary system (HPS). We studied the function (anterior and posterior pituitary hormonal secretion) and morphology using magnetic resonance imaging (MRI) of the HPS in 17 adult patients (seven males, median age 35 years, range 18-59 years) with multisystem LCH. We also evaluated the evolution of structural HPS abnormalities in relation to pituitary function and response to treatment in 12 of these patients during a median follow-up period of 3.75 years (range 1.5-10 years). Of the 17 patients, 14 (82%) had abnormal HPS imaging, and 12 (70%) had more than one area involved. Lack of the bright spot of the posterior pituitary lobe was typically found in all patients with the diagnosis of diabetes insipidus (DI). Eight patients (47%) had infundibular enlargement, six (35%) pituitary infiltration, four (24%) partially or completely empty sella, three (18%) hypothalamic involvement, and two (12%) infundibular atrophy. DI was found in 16 patients (94%) and anterior pituitary hormonal deficiency (APHD) in 10 patients (59%); two patients had single (12%) and 8 (47%) multiple APHD. During the follow-up period there was improvement of the initially demonstrated HPS pathology in seven (47%) patients, and five (33%) of them had received at least one form of treatment. APHD and DI persisted in all patients except in one in whom established gonadotrophin deficiency recovered. In summary, DI and APHD are very common in patients with multisystem LCH and are almost always associated with abnormal HPS imaging. (orig.)

  8. Hematopoietic cell crisis: An early stage of evolving myeloid leukemia following radiation exposure

    International Nuclear Information System (INIS)

    Seed, T.M.

    1990-01-01

    Under select radiological conditions, chronic radiation exposure elicits a high incidence of myeloproliferative disease, principally myeloid leukemia (ML), in beagles. Previously we demonstrated that for full ML expression, a four-stage preclinical sequence is required, namely (1) suppression, (2) recovery, (3) accommodation, and (4) preleukemic transition. Within this pathological sequence, a critical early event has been identified as the acquisition of radioresistance by hematopoietic progenitors that serves to mediate a newfound regenerative hematopoietic capacity. As such, this event ''sets the stage'' for preleukemic progression by initiating progression from preclinical phase 1 to 2. Due to the nature of target cell suppression, the induction of crisis, and the outgrowth of progenitors with altered phenotypes, this preleukemic event resembles the ''immortalization'' step of the in vitro transformation sequence following induction with either physical and chemical carcinogens. The radiological, temporal, and biological dictates governing this event have been extensively evaluated and will be discussed in light of their role in the induction and progression of chronic radiation leukemia. 35 refs., 2 tabs

  9. Hematopoietic cell crisis: An early stage of evolving myeloid leukemia following radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Seed, T.M.

    1990-01-01

    Under select radiological conditions, chronic radiation exposure elicits a high incidence of myeloproliferative disease, principally myeloid leukemia (ML), in beagles. Previously we demonstrated that for full ML expression, a four-stage preclinical sequence is required, namely (1) suppression, (2) recovery, (3) accommodation, and (4) preleukemic transition. Within this pathological sequence, a critical early event has been identified as the acquisition of radioresistance by hematopoietic progenitors that serves to mediate a newfound regenerative hematopoietic capacity. As such, this event sets the stage'' for preleukemic progression by initiating progression from preclinical phase 1 to 2. Due to the nature of target cell suppression, the induction of crisis, and the outgrowth of progenitors with altered phenotypes, this preleukemic event resembles the immortalization'' step of the in vitro transformation sequence following induction with either physical and chemical carcinogens. The radiological, temporal, and biological dictates governing this event have been extensively evaluated and will be discussed in light of their role in the induction and progression of chronic radiation leukemia. 35 refs., 2 tabs.

  10. Cell Growth Rate Dictates the Onset of Glass to Fluidlike Transition and Long Time Superdiffusion in an Evolving Cell Colony

    Science.gov (United States)

    Malmi-Kakkada, Abdul N.; Li, Xin; Samanta, Himadri S.; Sinha, Sumit; Thirumalai, D.

    2018-04-01

    Collective migration dominates many phenomena, from cell movement in living systems to abiotic self-propelling particles. Focusing on the early stages of tumor evolution, we enunciate the principles involved in cell dynamics and highlight their implications in understanding similar behavior in seemingly unrelated soft glassy materials and possibly chemokine-induced migration of CD 8+T cells. We performed simulations of tumor invasion using a minimal three-dimensional model, accounting for cell elasticity and adhesive cell-cell interactions, as well as cell birth and death, to establish that cell-growth-rate-dependent tumor expansion results in the emergence of distinct topological niches. Cells at the periphery move with higher velocity perpendicular to the tumor boundary, while the motion of interior cells is slower and isotropic. The mean-square displacement Δ (t ) of cells exhibits glassy behavior at times comparable to the cell cycle time, while exhibiting superdiffusive behavior, Δ (t )≈tα (α >1 ), at longer times. We derive the value of α ≈1.33 using a field theoretic approach based on stochastic quantization. In the process, we establish the universality of superdiffusion in a class of seemingly unrelated nonequilibrium systems. Superdiffusion at long times arises only if there is an imbalance between cell birth and death rates. Our findings for the collective migration, which also suggest that tumor evolution occurs in a polarized manner, are in quantitative agreement with in vitro experiments. Although set in the context of tumor invasion, the findings should also hold in describing the collective motion in growing cells and in active systems, where creation and annihilation of particles play a role.

  11. Maintaining evolvability.

    Science.gov (United States)

    Crow, James F

    2008-12-01

    Although molecular methods, such as QTL mapping, have revealed a number of loci with large effects, it is still likely that the bulk of quantitative variability is due to multiple factors, each with small effect. Typically, these have a large additive component. Conventional wisdom argues that selection, natural or artificial, uses up additive variance and thus depletes its supply. Over time, the variance should be reduced, and at equilibrium be near zero. This is especially expected for fitness and traits highly correlated with it. Yet, populations typically have a great deal of additive variance, and do not seem to run out of genetic variability even after many generations of directional selection. Long-term selection experiments show that populations continue to retain seemingly undiminished additive variance despite large changes in the mean value. I propose that there are several reasons for this. (i) The environment is continually changing so that what was formerly most fit no longer is. (ii) There is an input of genetic variance from mutation, and sometimes from migration. (iii) As intermediate-frequency alleles increase in frequency towards one, producing less variance (as p --> 1, p(1 - p) --> 0), others that were originally near zero become more common and increase the variance. Thus, a roughly constant variance is maintained. (iv) There is always selection for fitness and for characters closely related to it. To the extent that the trait is heritable, later generations inherit a disproportionate number of genes acting additively on the trait, thus increasing genetic variance. For these reasons a selected population retains its ability to evolve. Of course, genes with large effect are also important. Conspicuous examples are the small number of loci that changed teosinte to maize, and major phylogenetic changes in the animal kingdom. The relative importance of these along with duplications, chromosome rearrangements, horizontal transmission and polyploidy

  12. Role of chemotherapy in the treatment of lung cancer: evolving strategies for non-small cell histologies

    Energy Technology Data Exchange (ETDEWEB)

    Muggia, F.M. (NYU Medical Center, New York); Blum, R.H.; Foreman, J.D.

    1984-01-01

    Lung cancer treatment has been considered to have made little progress except for advances in small cell carcinoma. For other histologies an attitude of nihilism has prevailed principally because of lack of effective systemic therapy and of no persuasive evidence that results could be improved by combined modality treatment. On the other hand, favorable results from surgery are confined to a small percent of all patients with this disease. This review emphasizes possibilities for progress in evolving new therapeutic strategies. Although improvement over other systemic therapies is modest, cisplatin-containing regimens yield more consistent response rates and apparent survival advantage relative to single agents. Immediate progression occurs in the minority of patients. In addition, regimens combining cisplatin with vinca alkaloids have no substantial deleterious effects on the lung, marrow or esophagus to aggravate radiation-induced complications. These features encourage the evolution of strategies which begin with chemotherapy and then use consolidation with radiation therapy. Clinical trials using these and newer strategies must be instituted if progress is to occur in the treatment of non-small cell histologies at all stages.

  13. Role of chemotherapy in the treatment of lung cancer: evolving strategies for non-small cell histologies

    International Nuclear Information System (INIS)

    Muggia, F.M.; Blum, R.H.; Foreman, J.D.

    1984-01-01

    Lung cancer treatment has been considered to have made little progress except for advances in small cell carcinoma. For other histologies an attitude of nihilism has prevailed principally because of lack of effective systemic therapy and of no persuasive evidence that results could be improved by combined modality treatment. On the other hand, favorable results from surgery are confined to a small percent of all patients with this disease. This review emphasizes possibilities for progress in evolving new therapeutic strategies. Although improvement over other systemic therapies is modest, cisplatin-containing regimens yield more consistent response rates and apparent survival advantage relative to single agents. Immediate progression occurs in the minority of patients. In addition, regimens combining cisplatin with vinca alkaloids have no substantial deleterious effects on the lung, marrow or esophagus to aggravate radiation-induced complications. These features encourage the evolution of strategies which begin with chemotherapy and then use consolidation with radiation therapy. Clinical trials using these and newer strategies must be instituted if progress is to occur in the treatment of non-small cell histologies at all stages

  14. Validating a Conceptual Framework for the Core Concept of "Cell-Cell Communication"

    Science.gov (United States)

    Michael, Joel; Martinkova, Patricia; McFarland, Jenny; Wright, Ann; Cliff, William; Modell, Harold; Wenderoth, Mary Pat

    2017-01-01

    We have created and validated a conceptual framework for the core physiology concept of "cell-cell communication." The conceptual framework is composed of 51 items arranged in a hierarchy that is, in some instances, four levels deep. We have validated it with input from faculty who teach at a wide variety of institutional types. All…

  15. Validating a Conceptual Framework for the Core Concept of ”Cell-cell Communication”

    Czech Academy of Sciences Publication Activity Database

    Michael, J.; Martinková, Patrícia; McFarland, J.L.; Wright, A.; Cliff, W.; Modell, H.; Wenderoth, M.P.

    2017-01-01

    Roč. 41, č. 2 (2017), s. 260-265 ISSN 1043-4046 R&D Projects: GA ČR GJ15-15856Y Institutional support: RVO:67985807 Keywords : conceptual framework * core concept * cell-cell communication * physiology Subject RIV: AM - Education OBOR OECD: Education , general; including training, pedagogy, didactics [and education systems] Impact factor: 1.755, year: 2016

  16. New concepts for building vocabulary for cell image ontologies.

    Science.gov (United States)

    Plant, Anne L; Elliott, John T; Bhat, Talapady N

    2011-12-21

    There are significant challenges associated with the building of ontologies for cell biology experiments including the large numbers of terms and their synonyms. These challenges make it difficult to simultaneously query data from multiple experiments or ontologies. If vocabulary terms were consistently used and reused across and within ontologies, queries would be possible through shared terms. One approach to achieving this is to strictly control the terms used in ontologies in the form of a pre-defined schema, but this approach limits the individual researcher's ability to create new terms when needed to describe new experiments. Here, we propose the use of a limited number of highly reusable common root terms, and rules for an experimentalist to locally expand terms by adding more specific terms under more general root terms to form specific new vocabulary hierarchies that can be used to build ontologies. We illustrate the application of the method to build vocabularies and a prototype database for cell images that uses a visual data-tree of terms to facilitate sophisticated queries based on a experimental parameters. We demonstrate how the terminology might be extended by adding new vocabulary terms into the hierarchy of terms in an evolving process. In this approach, image data and metadata are handled separately, so we also describe a robust file-naming scheme to unambiguously identify image and other files associated with each metadata value. The prototype database http://sbd.nist.gov/ consists of more than 2000 images of cells and benchmark materials, and 163 metadata terms that describe experimental details, including many details about cell culture and handling. Image files of interest can be retrieved, and their data can be compared, by choosing one or more relevant metadata values as search terms. Metadata values for any dataset can be compared with corresponding values of another dataset through logical operations. Organizing metadata for cell imaging

  17. New concepts for building vocabulary for cell image ontologies

    Directory of Open Access Journals (Sweden)

    Plant Anne L

    2011-12-01

    Full Text Available Abstract Background There are significant challenges associated with the building of ontologies for cell biology experiments including the large numbers of terms and their synonyms. These challenges make it difficult to simultaneously query data from multiple experiments or ontologies. If vocabulary terms were consistently used and reused across and within ontologies, queries would be possible through shared terms. One approach to achieving this is to strictly control the terms used in ontologies in the form of a pre-defined schema, but this approach limits the individual researcher's ability to create new terms when needed to describe new experiments. Results Here, we propose the use of a limited number of highly reusable common root terms, and rules for an experimentalist to locally expand terms by adding more specific terms under more general root terms to form specific new vocabulary hierarchies that can be used to build ontologies. We illustrate the application of the method to build vocabularies and a prototype database for cell images that uses a visual data-tree of terms to facilitate sophisticated queries based on a experimental parameters. We demonstrate how the terminology might be extended by adding new vocabulary terms into the hierarchy of terms in an evolving process. In this approach, image data and metadata are handled separately, so we also describe a robust file-naming scheme to unambiguously identify image and other files associated with each metadata value. The prototype database http://sbd.nist.gov/ consists of more than 2000 images of cells and benchmark materials, and 163 metadata terms that describe experimental details, including many details about cell culture and handling. Image files of interest can be retrieved, and their data can be compared, by choosing one or more relevant metadata values as search terms. Metadata values for any dataset can be compared with corresponding values of another dataset through logical

  18. The Turbo-Fuel-Cell 1.0 - family concept

    Science.gov (United States)

    Berg, H. P.; Himmelberg, A.; Lehmann, M.; Dückershoff, R.; Neumann, M.

    2018-01-01

    The “Turbo-Fuel-Cell-Technology” has been described as a MGT-SOFC hybrid system consisting of a recuperated micro gas turbine (MGT) process with an embedded solid oxide fuel cell (SOFC) subsystem. SOFC stacks are connected to “SOFC stack grapes” and are equipped with the so called HEXAR-Module. This module is composed of a high-temperature heat exchanger (HEX), an afterburner (A) and a steam reformer (R). The MGT-concept is based on a generator driven directly by the turbomachine and a recuperator, which returns the exhaust heat to the pressurized compressor outlet air. This provides the necessary base for a highly effective, pure MGT process and the “MGT-SOFC-high-efficiency process”. This paper describes the concept and the thermodynamic background of a highly effective and compact design of the “Turbo-Fuel-Cell 1.0-Family” in the electrical performance class from 100 to 500 kW. The technological state of the system is shown and a rating of the system with comparative parameters is discussed. It becomes visible that all necessary basic technologies should be available and that the technology (for stationary applications) can have the “entry into services (E.I.S.)” in the next 10 years. The MGT-SOFC performance map under different operation conditions is discussed. This article also provides an overview of the research on MGT-SOFC-Systems and the scenario of an energy supply network and a mobile energy conversion of the future introduction.

  19. New concepts in sickle cell anemia | Chiabi | Clinics in Mother and ...

    African Journals Online (AJOL)

    New concepts in sickle cell anemia. ... Abstract. Current knowledge on the pathophysiology of sickle cell anemia is reviewed and potential therapeutic options are reviewed and ... Clinics in Mother and Child Health Vol. ... HOW TO USE AJOL.

  20. Critérios diagnósticos para os transtornos alimentares: conceitos em evolução Diagnostic criteria for eating disorders: evolving concepts

    Directory of Open Access Journals (Sweden)

    Angélica de Medeiros Claudino

    2002-12-01

    Full Text Available O presente artigo apresenta o "estado de arte" da discussão acerca dos critérios diagnósticos atuais dos transtornos alimentares: Anorexia Nervosa (AN, Bulimia Nervosa (BN e Transtorno da Compulsão Alimentar Periódica (TCAP. Dentre os aspectos controversos da AN, destacam-se: a concepção da distorção de imagem corporal, a necessidade da presença de amenorréia para o diagnóstico e a possibilidade de manifestação de AN sem seu aspecto característico, o medo de engordar, em culturas não ocidentalizadas. Quanto à BN, discute-se especialmente a concepção de compulsão alimentar sua freqüência e duração necessárias para o diagnóstico. O artigo apresenta também os critérios sugeridos para o diagnóstico de TCAP e comenta sua difícil distinção com a BN não purgativa. As questões aqui discutidas possibilitarão o aprimoramento da nosologia da área.This article presents the "the state of art" of the discussion over the current diagnostic criteria for eating disorders: Anorexia Nervosa (AN, Bulimia Nervosa (BN and Binge-Eating Disorder (BED. Within the controversial aspects of AN, it is outlined: the conception of body image disturbance, the necessity of amenorrhea fpr the diagnosis and the possibility of AN without its characteristic aspect, the morbid fear of weight, in not Westernized cultures. For BN, it is specially discussed the conception of binge-eating and the frequency and duration of episodes necessary for the diagnosis. The article also presents the suggested criteria for BED diagnosis and comments on its difficult distinction from non-purging BN . The issues here discussed shall improve the nosology in the field.

  1. Microscopic Colitis Evolved Into Inflammatory Bowel Diseases Is Characterized by Increased Th1/Tc1 Cells in Colonic Mucosal Lamina Propria.

    Science.gov (United States)

    Li, Ji; Yan, Yuchu; Meng, Ziran; Liu, Shuhong; Beck, Paul L; Ghosh, Subrata; Qian, Jiaming; Gui, Xianyong

    2017-10-01

    An association between microscopic colitis (MC), i.e., lymphocytic colitis (LC) and collagenous colitis (CC), and inflammatory bowel diseases (IBD) has been noticed. A subset of MC cases may evolve into IBD, and IBD in remission may present as MC in a histologic pattern. Moreover, MC and IBD may coexist in different regions of the bowel. A link between MC and IBD in their pathogenesis is, therefore, suggested. Abnormal mucosal immunity is likely the key. We reviewed 2324 MC cases in Calgary over 14 years and identified 20 cases evolved into IBD (IBD transformers). 13 of them were further investigated for colonic mucosal lamina propria mononuclear cells (LPMNCs), as opposed to 22 cases whose MC resolved. On their index colonic biopsy immunohistochemistry was performed to detect major T cell subsets characterized by key cytokines and master transcription factors (IFNγ and T-bet for Th1/Tc1, GATA-3 for Th2/Tc2, IL-17 and RORc for Th17/Tc17, FoxP3 for Treg/Tcreg) as well as TNFα + cells (partly representing Th1). LPMNCs positive for each marker were counted (average number per high-power field). IBD transformers had increased IFNγ + , T-bet + , TNF-α + , and GATA-3 + LPMNCs compared to the MC-resolved cases. The LC-to-IBD subgroup had increased IFNγ + and GATA-3 + cells compared to the LC-resolved subgroup. The CC-to-IBD subgroup had increased T-bet + , TNF-α + , and GATA-3 + cells compared to the CC-resolved subgroup. Among MC-resolved patients, more TNF-α + and RORc + cells were seen in LC than in CC. Th1/Tc1- and TNFα-producing cells, and likely a subset of Th2/Tc2 cells as well, may be involved in the MC-to-IBD transformation.

  2. The apolipoprotein L family of programmed cell death and immunity genes rapidly evolved in primates at discrete sites of host-pathogen interactions.

    Science.gov (United States)

    Smith, Eric E; Malik, Harmit S

    2009-05-01

    Apolipoprotein L1 (APOL1) is a human protein that confers immunity to Trypanosoma brucei infections but can be countered by a trypanosome-encoded antagonist SRA. APOL1 belongs to a family of programmed cell death genes whose proteins can initiate host apoptosis or autophagic death. We report here that all six members of the APOL gene family (APOL1-6) present in humans have rapidly evolved in simian primates. APOL6, furthermore, shows evidence of an adaptive sweep during recent human evolution. In each APOL gene tested, we found rapidly evolving codons in or adjacent to the SRA-interacting protein domain (SID), which is the domain of APOL1 that interacts with SRA. In APOL6, we also found a rapidly changing 13-amino-acid cluster in the membrane-addressing domain (MAD), which putatively functions as a pH sensor and regulator of cell death. We predict that APOL genes are antagonized by pathogens by at least two distinct mechanisms: SID antagonists, which include SRA, that interact with the SID of various APOL proteins, and MAD antagonists that interact with the MAD hinge base of APOL6. These antagonists either block or prematurely cause APOL-mediated programmed cell death of host cells to benefit the infecting pathogen. These putative interactions must occur inside host cells, in contrast to secreted APOL1 that trafficks to the trypanosome lysosome. Hence, the dynamic APOL gene family appears to be an important link between programmed cell death of host cells and immunity to pathogens.

  3. A computational method for the coupled solution of reaction-diffusion equations on evolving domains and manifolds: Application to a model of cell migration and chemotaxis.

    Science.gov (United States)

    MacDonald, G; Mackenzie, J A; Nolan, M; Insall, R H

    2016-03-15

    In this paper, we devise a moving mesh finite element method for the approximate solution of coupled bulk-surface reaction-diffusion equations on an evolving two dimensional domain. Fundamental to the success of the method is the robust generation of bulk and surface meshes. For this purpose, we use a novel moving mesh partial differential equation (MMPDE) approach. The developed method is applied to model problems with known analytical solutions; these experiments indicate second-order spatial and temporal accuracy. Coupled bulk-surface problems occur frequently in many areas; in particular, in the modelling of eukaryotic cell migration and chemotaxis. We apply the method to a model of the two-way interaction of a migrating cell in a chemotactic field, where the bulk region corresponds to the extracellular region and the surface to the cell membrane.

  4. Evolvable synthetic neural system

    Science.gov (United States)

    Curtis, Steven A. (Inventor)

    2009-01-01

    An evolvable synthetic neural system includes an evolvable neural interface operably coupled to at least one neural basis function. Each neural basis function includes an evolvable neural interface operably coupled to a heuristic neural system to perform high-level functions and an autonomic neural system to perform low-level functions. In some embodiments, the evolvable synthetic neural system is operably coupled to one or more evolvable synthetic neural systems in a hierarchy.

  5. Animal and plant stem cells concepts, propagation and engineering

    CERN Document Server

    Pavlović, Mirjana

    2017-01-01

    This book provides a multifaceted look into the world of stem cells and explains the similarities and differences between plant and human stem cells. It explores the intersection between animals and plants and explains their cooperative role in bioengineering studies. The book treats both theoretical and practical aspects of stem cell research. It covers the advantages and limitations of many common applications related to stem cells: their sources, categories, engineering of these cells, reprogramming of their functions, and their role as novel cellular therapeutic approach. Written by experts in the field, the book focuses on aspects of stem cells ranging from expansion-propagation to metabolic reprogramming. It introduces the emergence of cancer stem cells and different modalities in targeted cancer stem cell therapies. It is a valuable source of fresh information for academics and researchers, examining molecular mechanisms of animal and plant stem cell regulation and their usage for therapeutic applicati...

  6. Mice divergently selected for high and low basal metabolic rates evolved different cell size and organ mass.

    Science.gov (United States)

    Maciak, S; Bonda-Ostaszewska, E; Czarnołęski, M; Konarzewski, M; Kozłowski, J

    2014-03-01

    Evolution of metabolic rates of multicellular organisms is hypothesized to reflect the evolution of their cell architecture. This is likely to stem from a tight link between the sizes of cells and nuclei, which are expected to be inversely related to cell metabolism. Here, we analysed basal metabolic rate (BMR), internal organ masses and the cell/nucleus size in different tissues of laboratory mice divergently selected for high/low mass-corrected BMR and four random-bred mouse lines. Random-bred lines had intermediate levels of BMR as compared to low- and high-BMR lines. Yet, this pattern was only partly consistent with the between-line differences in cell/nucleus sizes. Erythrocytes and skin epithelium cells were smaller in the high-BMR line than in other lines, but the cells of low-BMR and random-bred mice were similar in size. On the other hand, the size of hepatocytes, kidney proximal tubule cells and duodenum enterocytes were larger in high-BMR mice than other lines. All cell and nucleus sizes were positively correlated, which supports the role of the nucleus in cell size regulation. Our results suggest that the evolution of high BMR involves a reduction in cell size in specialized tissues, whose functions are primarily dictated by surface-to-volume ratios, such as erythrocytes. High BMR may, however, also incur an increase in cell size in tissues with an intense transcription and translation, such as hepatocytes. © 2014 The Authors. Journal of Evolutionary Biology © 2014 European Society For Evolutionary Biology.

  7. Cytokines and beta-cell biology: from concept to clinical translation

    DEFF Research Database (Denmark)

    Donath, M.Y.; Storling, J.; Berchtold, L.A.

    2007-01-01

    The tale of cytokines and the beta-cell is a long story, starting with in vitro discovery in 1984, evolving via descriptive and phenomenological studies to detailed mapping of the signalling pathways, gene- and protein expression patterns, molecular and biochemical effector mechanisms to in vivo...

  8. Evolving Identification of Blood Cells Associated with Clinically Isolated Syndrome: Importance of Time since Clinical Presentation and Diagnostic MRI.

    Science.gov (United States)

    Trend, Stephanie; Jones, Anderson P; Geldenhuys, Sian; Byrne, Scott N; Fabis-Pedrini, Marzena J; Nolan, David; Booth, David R; Carroll, William M; Lucas, Robyn M; Kermode, Allan G; Hart, Prue H

    2017-06-15

    It is not clear how the profile of immune cells in peripheral blood differs between patients with clinically isolated syndrome (CIS) and healthy controls (HC). This study aimed to identify a CIS peripheral blood signature that may provide clues for potential immunomodulatory approaches early in disease. Peripheral blood mononuclear cells (PBMCs) were collected from 18 people with CIS, 19 HC and 13 individuals with other demyelinating conditions (ODC) including multiple sclerosis (MS). Individuals with CIS separated into two groups, namely those with early (≤14 days post-diagnostic magnetic resonance imaging (MRI); n = 6) and late (≥27 days; n = 12) blood sampling. Transitional B cells were increased in the blood of CIS patients independently of when blood was taken. However, there were two time-dependent effects found in the late CIS group relative to HC, including decreased CD56bright NK cells, which correlated significantly with time since MRI, and increased CD141+ myeloid dendritic cell (mDC2) frequencies. Higher CD1c+ B cells and lower non-classical monocyte frequencies were characteristic of more recent demyelinating disease activity (ODC and early CIS). Analysing cell populations by time since symptoms (subjective) and diagnostic MRI (objective) may contribute to understanding CIS.

  9. A neighbourhood evolving network model

    International Nuclear Information System (INIS)

    Cao, Y.J.; Wang, G.Z.; Jiang, Q.Y.; Han, Z.X.

    2006-01-01

    Many social, technological, biological and economical systems are best described by evolved network models. In this short Letter, we propose and study a new evolving network model. The model is based on the new concept of neighbourhood connectivity, which exists in many physical complex networks. The statistical properties and dynamics of the proposed model is analytically studied and compared with those of Barabasi-Albert scale-free model. Numerical simulations indicate that this network model yields a transition between power-law and exponential scaling, while the Barabasi-Albert scale-free model is only one of its special (limiting) cases. Particularly, this model can be used to enhance the evolving mechanism of complex networks in the real world, such as some social networks development

  10. An artemisinin-mediated ROS evolving and dual protease light-up nanocapsule for real-time imaging of lysosomal tumor cell death.

    Science.gov (United States)

    Huang, Liwei; Luo, Yingping; Sun, Xian; Ju, Huangxian; Tian, Jiangwei; Yu, Bo-Yang

    2017-06-15

    Lysosomes are critical organelles for cellular homeostasis and can be used as potential targets to kill tumor cells from inside. Many photo-therapeutic methods have been developed to overproduce reactive oxygen species (ROS) to trigger lysosomal membrane permeabilization (LMP)-associated cell death pathway. However, these technologies rely on extra irradiation to activate the photosensitizers, which limits the applications in treating deep seated tumors and widespread metastatic lesions. This work reports a multifunctional nanocapsule to achieve targeted lysosomal tumor cell death without irradiation and real-time monitoring of drug effect through encapsulating artemisinin and dual protease light-up nanoprobe in a folate-functionalized liposome. The nanocapsule can be specifically uptaken by tumor cells via folate receptor-mediated endocytosis to enter lysosomes, in which artemisinin reacts with ferrous to generate ROS for LMP-associated cell death. By virtue of confocal fluorescence imaging, the artemisinin location in lysosome, ROS-triggered LMP and ultimate cell apoptosis can be visualized with the cathepsin B and caspase-3 activatable nanoprobe. Notably, the artemisinin-mediated ROS evolving for tumor therapy and real-time therapeutic monitoring were successfully implemented by living imaging in tumor-bearing mice, which broaden the nanocapsule for in vivo theranostics and may offer new opportunities for precise medicine. Copyright © 2016 Elsevier B.V. All rights reserved.

  11. Evolving concepts and opportunities in soil conservation

    Directory of Open Access Journals (Sweden)

    Julian Dumanski

    2015-03-01

    The paper discusses some of the new driving forces, new international programs, and new potential partners in soil conservation. Increasingly, international efforts to mitigate land degradation are shifting from studies of the biophysical processes to improving the global, national and local enabling policy environment, as well as mainstreaming of soil conservation into national and regional policies and programs. Also, increased emphasis is placed on economic instruments and international markets, such as carbon trading, and incorporation of non-market values in ecosystem investment, such as payment for ecosystem services, certification schemes, etc. The paper discusses some of the opportunities for soil conservation that accrue from these new driving forces.

  12. Evolving Concepts in Transcatheter Aortic Valve Implantation

    NARCIS (Netherlands)

    Nijhoff, F.

    2015-01-01

    Part I of the present thesis is dedicated to implantation technique and the clinical performance of new valve prostheses. A satisfactory TAVI result not solely depends on patient characteristics, but also relies on proper valve positioning and final placement. Moreover, prosthetic design is

  13. Periodic Virtual Cell Manufacturing (P-VCM) - Concept, Design and Operation

    NARCIS (Netherlands)

    Slomp, Jannes; Krushinsky, Dimitry; Caprihan, Rahul

    2011-01-01

    This paper presents and discusses the concept of Periodic Virtual Cell Manufacturing (P-VCM). After giving an illustrative example of the operation and design complexity of a P-VCM system, we present an industrial case to study the applicability of the concept. The illustrative example and the

  14. An evolved ribosome-inactivating protein targets and kills human melanoma cells in vitro and in vivo

    Directory of Open Access Journals (Sweden)

    Green David E

    2010-02-01

    Full Text Available Abstract Background Few treatment options exist for patients with metastatic melanoma, resulting in poor prognosis. One standard treatment, dacarbazine (DTIC, shows low response rates ranging from 15 to 25 percent with an 8-month median survival time. The development of targeted therapeutics with novel mechanisms of action may improve patient outcome. Ribosome-inactivating proteins (RIPs such as Shiga-like Toxin 1 (SLT-1 represent powerful scaffolds for developing selective anticancer agents. Here we report the discovery and properties of a single chain ribosome-inactivating protein (scRIP derived from the cytotoxic A subunit of SLT-1 (SLT-1A, harboring the 7-amino acid peptide insertion IYSNKLM (termed SLT-1AIYSNKLM allowing the toxin variant to selectively target and kill human melanoma cells. Results SLT-1AIYSNKLM was able to kill 7 of 8 human melanoma cell lines. This scRIP binds to 518-A2 human melanoma cells with a dissociation constant of 18 nM, resulting in the blockage of protein synthesis and apoptosis in such cells. Biodistribution and imaging studies of radiolabeled SLT-1AIYSNKLM administered intravenously into SCID mice bearing a human melanoma xenograft indicate that SLT-1AIYSNKLM readily accumulates at the tumor site as opposed to non-target tissues. Furthermore, the co-administration of SLT-1AIYSNKLM with DTIC resulted in tumor regression and greatly increased survival in this mouse xenograft model in comparison to DTIC or SLT-1AIYSNKLM treatment alone (115 day median survival versus 46 and 47 days respectively; P values IYSNKLM is stable in serum and its intravenous administration resulted in modest immune responses following repeated injections in CD1 mice. Conclusions These results demonstrate that the evolution of a scRIP template can lead to the discovery of novel cancer cell-targeted compounds and in the case of SLT-1AIYSNKLM can specifically kill human melanoma cells in vitro and in vivo.

  15. New concepts in assessing sickle cell disease severity

    NARCIS (Netherlands)

    Schnog, JJB; Lard, LR; Rojer, RA; Van der Dijs, FPL; Muskiet, FAJ; Duits, AJ

    Vasoocclusion leads to pain, chronic organ damage, and a decreased life expectancy in patients with sickle cell disease. Therapeutic options for sickle cell disease have usually been evaluated according to their capacity for reducing the frequency of vasoocclusive crises requiring clinical

  16. An Overview of a Regenerative Fuel Cell Concept for a Mars Surface Mobile Element (Mars Rover)

    Science.gov (United States)

    Andersson, T.

    2018-04-01

    This paper outlines an overview of a regenerative fuel cell concept for a Mars rover. The objectives of the system are to provide electrical and thermal power during the Mars night and to provide electrical power for the operational cycles.

  17. Evolvability as a Quality Attribute of Software Architectures

    NARCIS (Netherlands)

    Ciraci, S.; van den Broek, P.M.; Duchien, Laurence; D'Hondt, Maja; Mens, Tom

    We review the definition of evolvability as it appears on the literature. In particular, the concept of software evolvability is compared with other system quality attributes, such as adaptability, maintainability and modifiability.

  18. Simple Photovoltaic Cells for Exploring Solar Energy Concepts

    Science.gov (United States)

    Appleyard, S. J.

    2006-01-01

    Low-efficiency solar cells for educational purposes can be simply made in school or home environments using wet-chemistry techniques and readily available chemicals of generally low toxicity. Instructions are given for making solar cells based on the heterojunctions Cu/Cu[subscript 2]O, Cu[subscript 2]O/ZnO and Cu[subscript 2]S/ZnO, together with…

  19. Emerging concepts and future challenges in innate lymphoid cell biology

    Science.gov (United States)

    Artis, David

    2016-01-01

    Innate lymphoid cells (ILCs) are innate immune cells that are ubiquitously distributed in lymphoid and nonlymphoid tissues and enriched at mucosal and barrier surfaces. Three major ILC subsets are recognized in mice and humans. Each of these subsets interacts with innate and adaptive immune cells and integrates cues from the epithelium, the microbiota, and pathogens to regulate inflammation, immunity, tissue repair, and metabolic homeostasis. Although intense study has elucidated many aspects of ILC development, phenotype, and function, numerous challenges remain in the field of ILC biology. In particular, recent work has highlighted key new questions regarding how these cells communicate with their environment and other cell types during health and disease. This review summarizes new findings in this rapidly developing field that showcase the critical role ILCs play in directing immune responses through their ability to interact with a variety of hematopoietic and nonhematopoietic cells. In addition, we define remaining challenges and emerging questions facing the field. Finally, this review discusses the potential application of basic studies of ILC biology to the development of new treatments for human patients with inflammatory and infectious diseases in which ILCs play a role. PMID:27811053

  20. Evolving role of 2B4/CD244 in T and NK cell responses during virus infection

    Directory of Open Access Journals (Sweden)

    Stephen Noel Waggoner

    2012-12-01

    Full Text Available The signaling lymphocyte activation molecule (SLAM family receptor, 2B4/CD244, was first implicated in anti-viral immunity by the discovery that mutations of the SLAM-associated protein, SAP/SH2D1A, impaired 2B4-dependent stimulation of T and natural killer (NK cell anti-viral functions in X-linked lymphoproliferative (XLP syndrome patients with uncontrolled Epstein-Barr virus (EBV infections. Engagement of 2B4 has been variably shown to either activate or inhibit lymphocytes which express this receptor. While SAP expression is required for stimulatory functions of 2B4 on lymphocytes, it remains unclear whether inhibitory signals derived from 2B4 can predominate even in the presence of SAP. Regardless, mounting evidence suggests that 2B4 expression by NK and CD8 T cells is altered by virus infection in mice as well as in humans, and 2B4-mediated signaling may be an important determinant of effective immune control of chronic virus infections. In this review, recent findings regarding the expression and function of 2B4 as well as SAP on T and NK cells during virus infection is discussed, with a focus on the role of 2B4-CD48 interactions in crosstalk between innate and adaptive immunity.

  1. Evolved osmotolerant Escherichia coli mutants frequently exhibit defective N-acetylglucosamine catabolism and point mutations in cell shape-regulating protein MreB.

    Science.gov (United States)

    Winkler, James D; Garcia, Carlos; Olson, Michelle; Callaway, Emily; Kao, Katy C

    2014-06-01

    Biocatalyst robustness toward stresses imposed during fermentation is important for efficient bio-based production. Osmotic stress, imposed by high osmolyte concentrations or dense populations, can significantly impact growth and productivity. In order to better understand the osmotic stress tolerance phenotype, we evolved sexual (capable of in situ DNA exchange) and asexual Escherichia coli strains under sodium chloride (NaCl) stress. All isolates had significantly improved growth under selection and could grow in up to 0.80 M (47 g/liter) NaCl, a concentration that completely inhibits the growth of the unevolved parental strains. Whole genome resequencing revealed frequent mutations in genes controlling N-acetylglucosamine catabolism (nagC, nagA), cell shape (mrdA, mreB), osmoprotectant uptake (proV), and motility (fimA). Possible epistatic interactions between nagC, nagA, fimA, and proV deletions were also detected when reconstructed as defined mutations. Biofilm formation under osmotic stress was found to be decreased in most mutant isolates, coupled with perturbations in indole secretion. Transcriptional analysis also revealed significant changes in ompACGL porin expression and increased transcription of sulfonate uptake systems in the evolved mutants. These findings expand our current knowledge of the osmotic stress phenotype and will be useful for the rational engineering of osmotic tolerance into industrial strains in the future. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

  2. A clade in the QUASIMODO2 family evolved with vascular plants and supports a role for cell wall composition in adaptation to environmental changes.

    Science.gov (United States)

    Fuentes, Sara; Pires, Nuno; Østergaard, Lars

    2010-08-01

    The evolution of plant vascular tissue is tightly linked to the evolution of specialised cell walls. Mutations in the QUASIMODO2 (QUA2) gene from Arabidopsis thaliana were previously shown to result in cell adhesion defects due to reduced levels of the cell wall component homogalacturonic acid. In this study, we provide additional information about the role of QUA2 and its closest paralogues, QUASIMODO2 LIKE1 (QUL1) and QUL2. Within the extensive QUA2 family, our phylogenetic analysis shows that these three genes form a clade that evolved with vascular plants. Consistent with a possible role of this clade in vasculature development, QUA2 is highly expressed in the vascular tissue of embryos and inflorescence stems and overexpression of QUA2 resulted in temperature-sensitive xylem collapse. Moreover, in-depth characterisation of qua2 qul1 qul2 triple mutant and 35S::QUA2 overexpression plants revealed contrasting temperature-dependent stem development with dramatic effects on stem width. Taken together, our results suggest that the QUA2-specific clade contributed to the evolution of vasculature and illustrate the important role that modification of cell wall composition plays in the adaptation to changing environmental conditions, including changes in temperature.

  3. Communicability across evolving networks.

    Science.gov (United States)

    Grindrod, Peter; Parsons, Mark C; Higham, Desmond J; Estrada, Ernesto

    2011-04-01

    Many natural and technological applications generate time-ordered sequences of networks, defined over a fixed set of nodes; for example, time-stamped information about "who phoned who" or "who came into contact with who" arise naturally in studies of communication and the spread of disease. Concepts and algorithms for static networks do not immediately carry through to this dynamic setting. For example, suppose A and B interact in the morning, and then B and C interact in the afternoon. Information, or disease, may then pass from A to C, but not vice versa. This subtlety is lost if we simply summarize using the daily aggregate network given by the chain A-B-C. However, using a natural definition of a walk on an evolving network, we show that classic centrality measures from the static setting can be extended in a computationally convenient manner. In particular, communicability indices can be computed to summarize the ability of each node to broadcast and receive information. The computations involve basic operations in linear algebra, and the asymmetry caused by time's arrow is captured naturally through the noncommutativity of matrix-matrix multiplication. Illustrative examples are given for both synthetic and real-world communication data sets. We also discuss the use of the new centrality measures for real-time monitoring and prediction.

  4. Conception of dismantling cell for glove box with alpha contamination

    International Nuclear Information System (INIS)

    Mangin, D.

    1987-01-01

    The new dismantling cell of Valduc treats particularly alpha glove boxes. This cell is conceived to reduce the intervention inside for man with ventilated clothes and to reduce the volume of alpha wastes by utilization of manipulators and appropriate tools. The respect of low level norms (0.1 Ci/ton) for storage of alpha wastes conductes us to make a first decontamination, to ameliorate the detection in quantity of plutonium in the wastes and for wastes with a level upper the norm to make studies on decontamination by Freon 113 [fr

  5. The evolving roles of canonical WNT signaling in stem cells and tumorigenesis: Implications in targeted cancer therapies

    Science.gov (United States)

    Yang, Ke; Wang, Xin; Zhang, Hongmei; Wang, Zhongliang; Nan, Guoxin; Li, Yasha; Zhang, Fugui; Mohammed, Maryam K.; Haydon, Rex C.; Luu, Hue H.; Bi, Yang; He, Tong-Chuan

    2015-01-01

    The canonical WNT/β-catenin signaling pathway governs a myriad of biological processes underlying development and maintenance of adult tissue homeostasis, including regulation of stem cell self-renewal, cell proliferation, differentiation, and apoptosis. WNTs are secreted lipid-modified glycoproteins that act as short-range ligands to activate receptor-mediated signaling pathways. The hallmark of the canonical pathway is the activation of β-catenin mediated transcriptional activity. Canonical WNTs control the β-catenin dynamics as the cytoplasmic level of β-catenin is tightly regulated via phosphorylation by the ‘destruction complex’, consisting of glycogen synthase kinase 3β (GSK3β), casein kinase 1α (CK1α), the scaffold protein AXIN, and the tumor suppressor adenomatous polyposis coli (APC). Aberrant regulation of this signaling cascade is associated with varieties of human diseases, especially cancers. Over the past decade, significant progress has been made in understanding the mechanisms of canonical WNT signaling. In this review, we focus on the current understanding of WNT signaling at the extracellular, cytoplasmic membrane, and intracellular/nuclear levels, including the emerging knowledge of crosstalk with other pathways. Recent progresses in developing novel WNT pathway-targeted therapies will also be reviewed. Thus, this review is intended to serve as a refresher of the current understanding about the physiologic and pathogenic roles of WNT/β-catenin signaling pathway, and to outline potential therapeutic opportunities by targeting the canonical WNT pathway. PMID:26618721

  6. Bioportide: an emergent concept of bioactive cell-penetrating peptides

    Czech Academy of Sciences Publication Activity Database

    Howl, J.; Matou-Nasri, S.; West, D. C.; Farquhar, M.; Slaninová, Jiřina; Ostenson, C. G.; Zorko, M.; Ostlund, P.; Kumar, S.; Langel, U.; McKeating, J.; Jones, S.

    2012-01-01

    Roč. 69, č. 17 (2012), s. 2951-2966 ISSN 1420-682X Institutional research plan: CEZ:AV0Z40550506 Keywords : angiogenesis * bioportide * cell-penetrating peptide * second messenger * insulin secretion Subject RIV: CE - Biochemistry Impact factor: 5.615, year: 2012

  7. Stroke in sickle cell anemia: New concepts in diagnosis and ...

    African Journals Online (AJOL)

    Stroke is a devastating and potentially fatal complication of sickle cell disease. The highest incidence of cerebrovascular disease is in the first 10 years and especially between 2 to 5 years. Two types of stroke occur in these patients – infarctive and hemorrhagic strokes. While infarctive strokes occur frequently in children, ...

  8. The myeloma stem cell concept, revisited: From phenomenology to operational terms

    NARCIS (Netherlands)

    H.E. Johnsen (Hans); M. Bøgsted (Martin); A. Schmitz; Bødker, J.S. (Julie Støve); El-Galaly, T.C. (Tarec Christoffer); Johansen, P. (Preben); P. Valent (Peter); Zojer, N. (Niklas); E. van Valckenborgh (Els); Vanderkerken, K. (Karin); M. van Duin (Mark); P. Sonneveld (Pieter); M. Perez-Andres; A. Orfao (Alberto); K. Dybkær (Karen)

    2016-01-01

    textabstractThe concept of the myeloma stem cell may have important therapeutic implications, yet its demonstration has been hampered by a lack of consistency in terms and definitions. Here, we summarize the current documentation and propose single-cell in vitro studies for future translational

  9. Treatment of giant cell tumor of bone: Current concepts

    OpenAIRE

    Puri Ajay; Agarwal Manish

    2007-01-01

    Giant cell tumor (GCT) of bone though one of the commonest bone tumors encountered by an orthopedic surgeon continues to intrigue treating surgeons. Usually benign, they are locally aggressive and may occasionally undergo malignant transformation. The surgeon needs to strike a balance during treatment between reducing the incidence of local recurrence while preserving maximal function. Differing opinions pertaining to the use of adjuvants for extension of curettage, the relative role of bone ...

  10. The evolving role of chemotherapy and hematopoietic cell transplants in Ph-positive acute lymphoblastic leukemia in adults.

    Science.gov (United States)

    Litzow, M R; Fielding, A K; Luger, S M; Paietta, E; Ofran, Y; Rowe, J M; Goldstone, A H; Tallman, M S; Lazarus, H M

    2017-12-01

    The introduction of the tyrosine kinase inhibitors (TKI) into the treatment of patients with Ph or BCR-ABL1-positive acute lymphoblastic leukemia has revolutionized the treatment of this poor prognosis acute leukemia. The combination of TKI with chemotherapy has improved response rates and allowed more patients to proceed to allogeneic hematopoietic cell transplant (alloHCT). Older patients have excellent responses to TKI and corticosteroids or in combination with minimal chemotherapy. This raises the question as to whether patients require full-intensity chemotherapy with TKI to achieve molecular remissions. The pediatricians have proposed that cure is achievable without alloHCT in children. These results have suggested that many patients may not require traditional chemotherapy in addition to TKI to achieve remission, and that patients who achieve a negative minimal residual disease state may not require alloHCT. The data in support of these questions is presented here and a suggested future clinical trial design based on these data is proposed.

  11. Management concepts.

    Science.gov (United States)

    Bittner, Rhonda

    2006-01-01

    Management concepts evolve through time. Health care managers can learn new concepts by evaluating classical management strategies, as well as modern-day strategies. Focusing on quality improvement and team building can help managers align the goals of their departments with the goals of the organization, consequently improving patient care.

  12. Treatment of giant cell tumor of bone: Current concepts.

    Science.gov (United States)

    Puri, Ajay; Agarwal, Manish

    2007-04-01

    Giant cell tumor (GCT) of bone though one of the commonest bone tumors encountered by an orthopedic surgeon continues to intrigue treating surgeons. Usually benign, they are locally aggressive and may occasionally undergo malignant transformation. The surgeon needs to strike a balance during treatment between reducing the incidence of local recurrence while preserving maximal function.Differing opinions pertaining to the use of adjuvants for extension of curettage, the relative role of bone graft or cement to pack the defect and the management of recurrent lesions are some of the issues that offer topics for eternal debate.Current literature suggests that intralesional curettage strikes the best balance between controlling disease and preserving optimum function in the majority of the cases though there may be occasions where the extent of the disease mandates resection to ensure adequate disease clearance.An accompanying treatment algorithm helps outline the management strategy in GCT.

  13. Treatment of giant cell tumor of bone: Current concepts

    Directory of Open Access Journals (Sweden)

    Puri Ajay

    2007-01-01

    Full Text Available Giant cell tumor (GCT of bone though one of the commonest bone tumors encountered by an orthopedic surgeon continues to intrigue treating surgeons. Usually benign, they are locally aggressive and may occasionally undergo malignant transformation. The surgeon needs to strike a balance during treatment between reducing the incidence of local recurrence while preserving maximal function. Differing opinions pertaining to the use of adjuvants for extension of curettage, the relative role of bone graft or cement to pack the defect and the management of recurrent lesions are some of the issues that offer topics for eternal debate. Current literature suggests that intralesional curettage strikes the best balance between controlling disease and preserving optimum function in the majority of the cases though there may be occasions where the extent of the disease mandates resection to ensure adequate disease clearance. An accompanying treatment algorithm helps outline the management strategy in GCT.

  14. Cell labelling. Granule and platelet kinetics. Recent concepts

    International Nuclear Information System (INIS)

    Najean, Y.; Dresch, C.; Dassin, E.

    Some unsolved problems are reviewed concerning the lifetime of blood platelets, with special reference to excessive platelet consumption and its possible correction by anti-aggregation agents, in many vascular diseases. Regarding the production of platelets it is considered that the 75 Se-methionine labelling method alone offers a quantitative approach to the process and could be used for the physiological study of thrombopoietic factors. A short chapter is devoted to a survey of the points of agreement and disagreement regarding the lifetime of polynuclear cells and a tentative analysis of the reasons explaining the quite different results obtained with DFP and radiochromium labelling. Finally the methods used to study granule formation are criticized, though it is acknowledged that certain ideas useful in physiopathology have emerged from these different procedures [fr

  15. Using Mouse Mammary Tumor Cells to Teach Core Biology Concepts: A Simple Lab Module.

    Science.gov (United States)

    McIlrath, Victoria; Trye, Alice; Aguanno, Ann

    2015-06-18

    Undergraduate biology students are required to learn, understand and apply a variety of cellular and molecular biology concepts and techniques in preparation for biomedical, graduate and professional programs or careers in science. To address this, a simple laboratory module was devised to teach the concepts of cell division, cellular communication and cancer through the application of animal cell culture techniques. Here the mouse mammary tumor (MMT) cell line is used to model for breast cancer. Students learn to grow and characterize these animal cells in culture and test the effects of traditional and non-traditional chemotherapy agents on cell proliferation. Specifically, students determine the optimal cell concentration for plating and growing cells, learn how to prepare and dilute drug solutions, identify the best dosage and treatment time course of the antiproliferative agents, and ascertain the rate of cell death in response to various treatments. The module employs both a standard cell counting technique using a hemocytometer and a novel cell counting method using microscopy software. The experimental procedure lends to open-ended inquiry as students can modify critical steps of the protocol, including testing homeopathic agents and over-the-counter drugs. In short, this lab module requires students to use the scientific process to apply their knowledge of the cell cycle, cellular signaling pathways, cancer and modes of treatment, all while developing an array of laboratory skills including cell culture and analysis of experimental data not routinely taught in the undergraduate classroom.

  16. Targeted disruption in mice of a neural stem cell-maintaining, KRAB-Zn finger-encoding gene that has rapidly evolved in the human lineage.

    Directory of Open Access Journals (Sweden)

    Huan-Chieh Chien

    Full Text Available Understanding the genetic basis of the physical and behavioral traits that separate humans from other primates is a challenging but intriguing topic. The adaptive functions of the expansion and/or reduction in human brain size have long been explored. From a brain transcriptome project we have identified a KRAB-Zn finger protein-encoding gene (M003-A06 that has rapidly evolved since the human-chimpanzee separation. Quantitative RT-PCR analysis of different human tissues indicates that M003-A06 expression is enriched in the human fetal brain in addition to the fetal heart. Furthermore, analysis with use of immunofluorescence staining, neurosphere culturing and Western blotting indicates that the mouse ortholog of M003-A06, Zfp568, is expressed mainly in the embryonic stem (ES cells and fetal as well as adult neural stem cells (NSCs. Conditional gene knockout experiments in mice demonstrates that Zfp568 is both an NSC maintaining- and a brain size-regulating gene. Significantly, molecular genetic analyses show that human M003-A06 consists of 2 equilibrated allelic types, H and C, one of which (H is human-specific. Combined contemporary genotyping and database mining have revealed interesting genetic associations between the different genotypes of M003-A06 and the human head sizes. We propose that M003-A06 is likely one of the genes contributing to the uniqueness of the human brain in comparison to other higher primates.

  17. Favorable Response of Metastatic Merkel Cell Carcinoma to Targeted 177Lu-DOTATATE Therapy: Will PRRT Evolve to Become an Important Approach in Receptor-Positive Cases?

    Science.gov (United States)

    Basu, Sandip; Ranade, Rohit

    2016-06-01

    This report illustrates an excellent partial response of Merkel cell carcinoma with multiple bilobar hepatic metastases to a single cycle of peptide receptor radionuclide therapy (PRRT) with (177)Lu-DOTATATE. This response, coupled with minimal side effects, warrants consideration of this therapy early in the disease course (rather than at an advanced stage after failure of other therapies) if the metastatic lesions exhibit adequate tracer avidity on somatostatin receptor-based imaging. Our patient showed progression of systemic disease after having undergone a second surgery and adjuvant radiotherapy to the head and neck, as well as chemotherapy, and hence was considered a candidate for PRRT. In a pretreatment study, the metastatic lesions demonstrated avidity to both somatostatin receptors and (18)F-FDG. Three months after the first cycle of treatment, when the patient was being evaluated for a second cycle, both imaging parameters showed evidence of a partial response that included nearly complete resolution of the two previously seen lesions. In view of the relatively good tolerability, minimal side effects, and targeted nature of the treatment, PRRT may evolve to become the first-line therapy for metastatic Merkel cell carcinoma and should be examined further in a larger number of patients. © 2016 by the Society of Nuclear Medicine and Molecular Imaging, Inc.

  18. The Hot Cell Radioactive Waste Concept of Forschungszentrum Juelich

    International Nuclear Information System (INIS)

    Pott, G.; Halaszovich, St.

    1999-01-01

    During the last 30 years extensive scientific examinations on radioactive metals,ceramics and fuel elements have been carried out, so that a high volume of waste has resulted. Also from the dismantling of irradiated facilities metallics waste has o be handed. Prior for equipment repair the hot cell involved has to be decontaminated and a large amount of lower active waste is produced. The waste is collected for conditioning and storing. There are different categories as: low active liquid waste, low active burnable waste, fuel waste, low and high active metallic waste. For each waste category special transport container are used. For the volume reduction our Waste Department is equipped with special facilities e.g.: furnace for burning, drying, liquids evaporators, hydraulic press for pelletizing, decontamination box for the dismantling ad cleaning of components. After conditioning the waste will be stored on site or transported to final storage in a salt mine (ERAM) . Special documentation has to be done for the acceptance of this waste

  19. A relativity concept in mesenchymal stromal cell manufacturing.

    Science.gov (United States)

    Martin, Ivan; De Boer, Jan; Sensebe, Luc

    2016-05-01

    Mesenchymal stromal cells (MSCs) are being experimentally tested in several biological systems and clinical settings with the aim of verifying possible therapeutic effects for a variety of indications. MSCs are also known to be heterogeneous populations, with phenotypic and functional features that depend heavily on the individual donor, the harvest site, and the culture conditions. In the context of this multidimensional complexity, a recurrent question is whether it is feasible to produce MSC batches as "standard" therapeutics, possibly within scalable manufacturing systems. Here, we provide a short overview of the literature on different culture methods for MSCs, including those employing innovative technologies, and of some typically assessed functional features (e.g., growth, senescence, genomic stability, clonogenicity, etc.). We then offer our perspective of a roadmap on how to identify and refine manufacturing systems for MSCs intended for specific clinical indications. We submit that the vision of producing MSCs according to a unique standard, although commercially attractive, cannot yet be scientifically substantiated. Instead, efforts should be concentrated on standardizing methods for characterization of MSCs generated by different groups, possibly covering a vast gamut of functionalities. Such assessments, combined with hypotheses on the therapeutic mode of action and associated clinical data, should ultimately allow definition of in-process controls and measurable release criteria for MSC manufacturing. These will have to be validated as predictive of potency in suitable pre-clinical models and of therapeutic efficacy in patients. Copyright © 2016 International Society for Cellular Therapy. Published by Elsevier Inc. All rights reserved.

  20. Concepts for the clinical use of stem cells in equine medicine

    DEFF Research Database (Denmark)

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

    2008-01-01

    experimental and empirical commercial use. A better understanding of equine stem cell biology and concepts is needed in order to develop and evaluate rational clinical applications in the horse. Controlled, well-designed studies of the basic biologic characteristics and properties of these cells are needed......Stem cells from various tissues hold great promise for their therapeutic use in horses, but so far efficacy or proof-of-principle has not been established. The basic characteristics and properties of various equine stem cells remain largely unknown, despite their increasingly widespread...

  1. Exploring Middle School Students' Conceptions of the Relationship between Genetic Inheritance and Cell Division

    Science.gov (United States)

    Williams, Michelle; DeBarger, Angela Haydel; Montgomery, Beronda L.; Zhou, Xuechun; Tate, Erika

    2012-01-01

    This study examines students' understanding of the normative connections between key concepts of cell division, including both mitosis and meiosis, and underlying biological principles that are critical for an in-depth understanding of genetic inheritance. Using a structural equation modeling method, we examine middle school students'…

  2. Mentoring: An Evolving Relationship.

    Science.gov (United States)

    Block, Michelle; Florczak, Kristine L

    2017-04-01

    The column concerns itself with mentoring as an evolving relationship between mentor and mentee. The collegiate mentoring model, the transformational transcendence model, and the humanbecoming mentoring model are considered in light of a dialogue with mentors at a Midwest university and conclusions are drawn.

  3. Methods Evolved by Observation

    Science.gov (United States)

    Montessori, Maria

    2016-01-01

    Montessori's idea of the child's nature and the teacher's perceptiveness begins with amazing simplicity, and when she speaks of "methods evolved," she is unveiling a methodological system for observation. She begins with the early childhood explosion into writing, which is a familiar child phenomenon that Montessori has written about…

  4. Cancer Stem Cells in Primary Liver Cancers: Pathological Concepts and Imaging Findings

    Energy Technology Data Exchange (ETDEWEB)

    Joo, Ijin [Department of Radiology, Seoul National University Hospital, Seoul 110-744 (Korea, Republic of); Kim, Haeryoung [Department of Pathology, Seoul National University Bundang Hospital, Seongnam 463-707 (Korea, Republic of); Lee, Jeong Min [Department of Radiology, Seoul National University Hospital, Seoul 110-744 (Korea, Republic of)

    2015-11-01

    There is accumulating evidence that cancer stem cells (CSCs) play an integral role in the initiation of hepatocarcinogenesis and the maintaining of tumor growth. Liver CSCs derived from hepatic stem/progenitor cells have the potential to differentiate into either hepatocytes or cholangiocytes. Primary liver cancers originating from CSCs constitute a heterogeneous histopathologic spectrum, including hepatocellular carcinoma, combined hepatocellular-cholangiocarcinoma, and intrahepatic cholangiocarcinoma with various radiologic manifestations. In this article, we reviewed the recent concepts of CSCs in the development of primary liver cancers, focusing on their pathological and radiological findings. Awareness of the pathological concepts and imaging findings of primary liver cancers with features of CSCs is critical for accurate diagnosis, prediction of outcome, and appropriate treatment options for patients.

  5. Cancer Stem Cells in Primary Liver Cancers: Pathological Concepts and Imaging Findings

    International Nuclear Information System (INIS)

    Joo, Ijin; Kim, Haeryoung; Lee, Jeong Min

    2015-01-01

    There is accumulating evidence that cancer stem cells (CSCs) play an integral role in the initiation of hepatocarcinogenesis and the maintaining of tumor growth. Liver CSCs derived from hepatic stem/progenitor cells have the potential to differentiate into either hepatocytes or cholangiocytes. Primary liver cancers originating from CSCs constitute a heterogeneous histopathologic spectrum, including hepatocellular carcinoma, combined hepatocellular-cholangiocarcinoma, and intrahepatic cholangiocarcinoma with various radiologic manifestations. In this article, we reviewed the recent concepts of CSCs in the development of primary liver cancers, focusing on their pathological and radiological findings. Awareness of the pathological concepts and imaging findings of primary liver cancers with features of CSCs is critical for accurate diagnosis, prediction of outcome, and appropriate treatment options for patients

  6. Concept of multiple-cell cavity for axion dark matter search

    Science.gov (United States)

    Jeong, Junu; Youn, SungWoo; Ahn, Saebyeok; Kim, Jihn E.; Semertzidis, Yannis K.

    2018-02-01

    In cavity-based axion dark matter search experiments exploring high mass regions, multiple-cavity design is under consideration as a method to increase the detection volume within a given magnet bore. We introduce a new idea, referred to as a multiple-cell cavity, which provides various benefits including a larger detection volume, simpler experimental setup, and easier phase-matching mechanism. We present the characteristics of this concept and demonstrate the experimental feasibility with an example of a double-cell cavity.

  7. A generic concept to overcome bandgap limitations for designing highly efficient multi-junction photovoltaic cells.

    Science.gov (United States)

    Guo, Fei; Li, Ning; Fecher, Frank W; Gasparini, Nicola; Ramirez Quiroz, Cesar Omar; Bronnbauer, Carina; Hou, Yi; Radmilović, Vuk V; Radmilović, Velimir R; Spiecker, Erdmann; Forberich, Karen; Brabec, Christoph J

    2015-07-16

    The multi-junction concept is the most relevant approach to overcome the Shockley-Queisser limit for single-junction photovoltaic cells. The record efficiencies of several types of solar technologies are held by series-connected tandem configurations. However, the stringent current-matching criterion presents primarily a material challenge and permanently requires developing and processing novel semiconductors with desired bandgaps and thicknesses. Here we report a generic concept to alleviate this limitation. By integrating series- and parallel-interconnections into a triple-junction configuration, we find significantly relaxed material selection and current-matching constraints. To illustrate the versatile applicability of the proposed triple-junction concept, organic and organic-inorganic hybrid triple-junction solar cells are constructed by printing methods. High fill factors up to 68% without resistive losses are achieved for both organic and hybrid triple-junction devices. Series/parallel triple-junction cells with organic, as well as perovskite-based subcells may become a key technology to further advance the efficiency roadmap of the existing photovoltaic technologies.

  8. The evolutionary reserve cell concept and model of cellular response induced by low doses of radiation

    International Nuclear Information System (INIS)

    Spitkovsky, D.M.; Talyzina, T.A.

    1995-01-01

    The model is based on the concept of programmed initiation of genetic damage in sub-populations of specific evolutionary reserve cells (ERC). The model quantitatively predicts a dose response of genetic lesions at low dose range and furnishes an explanation of the minimum observed in the dose-response curve at doses corresponding to one (on the average) event of energy deposition per ERC. The complex shape of the dose-response curve is demonstrated to result from superposition of processes in different sub-populations within the exposed cell population (at low doses mainly in ERC). Programmed initiation of genetic lesions in ERC requires two hits to cell membrane and probably, at the same time, to the cell nucleus. The equation for dicentric yield in human lymphocytes as a function of dose describes the experimental observations rather well. (Author)

  9. EVOLVE 2014 International Conference

    CERN Document Server

    Tantar, Emilia; Sun, Jian-Qiao; Zhang, Wei; Ding, Qian; Schütze, Oliver; Emmerich, Michael; Legrand, Pierrick; Moral, Pierre; Coello, Carlos

    2014-01-01

    This volume encloses research articles that were presented at the EVOLVE 2014 International Conference in Beijing, China, July 1–4, 2014.The book gathers contributions that emerged from the conference tracks, ranging from probability to set oriented numerics and evolutionary computation; all complemented by the bridging purpose of the conference, e.g. Complex Networks and Landscape Analysis, or by the more application oriented perspective. The novelty of the volume, when considering the EVOLVE series, comes from targeting also the practitioner’s view. This is supported by the Machine Learning Applied to Networks and Practical Aspects of Evolutionary Algorithms tracks, providing surveys on new application areas, as in the networking area and useful insights in the development of evolutionary techniques, from a practitioner’s perspective. Complementary to these directions, the conference tracks supporting the volume, follow on the individual advancements of the subareas constituting the scope of the confe...

  10. Bio Optofluidics Cell Sorter – cell-BOCS Concept and Applications

    DEFF Research Database (Denmark)

    Roth, Tue; Glückstad, Jesper

    2012-01-01

    The cell-BOCS is a novel microfluidics based cell-sorting instrument utilizing next generation optical trapping technology developed at the Technical University of Denmark. It is targeted emerging bio-medical research and diagnostics markets where it for certain applications offers a number...

  11. Evolving Procurement Organizations

    DEFF Research Database (Denmark)

    Bals, Lydia; Laine, Jari; Mugurusi, Godfrey

    Procurement has to find further levers and advance its contribution to corporate goals continuously. This places pressure on its organization in order to facilitate its performance. Therefore, procurement organizations constantly have to evolve in order to match these demands. A conceptual model...... and external contingency factors and having a more detailed look at the structural dimensions chosen, beyond the well-known characteristics of centralization, formalization, participation, specialization, standardization and size. From a theoretical perspective, it opens up insights that can be leveraged...

  12. Symbiotic Composition and Evolvability

    OpenAIRE

    Watson, Richard A.; Pollack, Jordan B.

    2001-01-01

    Several of the Major Transitions in natural evolution, such as the symbiogenic origin of eukaryotes from prokaryotes, share the feature that existing entities became the components of composite entities at a higher level of organisation. This composition of pre-adapted extant entities into a new whole is a fundamentally different source of variation from the gradual accumulation of small random variations, and it has some interesting consequences for issues of evolvability. In this paper we p...

  13. Evolvable Neural Software System

    Science.gov (United States)

    Curtis, Steven A.

    2009-01-01

    The Evolvable Neural Software System (ENSS) is composed of sets of Neural Basis Functions (NBFs), which can be totally autonomously created and removed according to the changing needs and requirements of the software system. The resulting structure is both hierarchical and self-similar in that a given set of NBFs may have a ruler NBF, which in turn communicates with other sets of NBFs. These sets of NBFs may function as nodes to a ruler node, which are also NBF constructs. In this manner, the synthetic neural system can exhibit the complexity, three-dimensional connectivity, and adaptability of biological neural systems. An added advantage of ENSS over a natural neural system is its ability to modify its core genetic code in response to environmental changes as reflected in needs and requirements. The neural system is fully adaptive and evolvable and is trainable before release. It continues to rewire itself while on the job. The NBF is a unique, bilevel intelligence neural system composed of a higher-level heuristic neural system (HNS) and a lower-level, autonomic neural system (ANS). Taken together, the HNS and the ANS give each NBF the complete capabilities of a biological neural system to match sensory inputs to actions. Another feature of the NBF is the Evolvable Neural Interface (ENI), which links the HNS and ANS. The ENI solves the interface problem between these two systems by actively adapting and evolving from a primitive initial state (a Neural Thread) to a complicated, operational ENI and successfully adapting to a training sequence of sensory input. This simulates the adaptation of a biological neural system in a developmental phase. Within the greater multi-NBF and multi-node ENSS, self-similar ENI s provide the basis for inter-NBF and inter-node connectivity.

  14. Evolved H II regions

    International Nuclear Information System (INIS)

    Churchwell, E.

    1975-01-01

    A probable evolutionary sequence of H II regions based on six distinct types of observed objects is suggested. Two examples which may deviate from this idealized sequence, are discussed. Even though a size-mean density relation of H II regions can be used as a rough indication of whether a nebula is very young or evolved, it is argued that such a relation is not likely to be useful for the quantitative assignment of ages to H II regions. Evolved H II regions appear to fit into one of four structural types: rings, core-halos, smooth structures, and irregular or filamentary structures. Examples of each type are given with their derived physical parameters. The energy balance in these nebulae is considered. The mass of ionized gas in evolved H II regions is in general too large to trace the nebula back to single compact H II regions. Finally, the morphological type of the Galaxy is considered from its H II region content. 2 tables, 2 figs., 29 refs

  15. [Merkel cell carcinoma: cutaneous manifestation of a highly malignant pre-/pro-B cell neoplasia? : Novel concept about the cellular origin of Merkel cell carcinoma].

    Science.gov (United States)

    Sauer, C M; Chteinberg, E; Rennspiess, D; Kurz, A K; Zur Hausen, A

    2017-03-01

    Merkel cell carcinoma (MCC) is a relatively rare but highly malignant non-melanoma skin cancer of the elderly and immunosuppressed patients. The discovery of the Merkel cell polyomavirus (MCPyV) in 2008 significantly impacted the understanding of the etiopathogenesis of MCC. MCPyV is clonally integrated into the MCC genome and approximately 80% of MCC are MCPyV-positive. Recent results of clinical trials using blockade of the PD-1 immune modulatory pathway are promising for the future treatment of MCC. Despite this major progress of the past few years, the cellular origin of MCC still remains obscure. Based on histomorphology, gene expression profiling, and molecular analyses, we have recently hypothesized that MCC originates from pre‑/pro-B cells. Here we review putative cells of MCC, including Merkel cells, (epi‑)dermal stem cells, and pro‑/pre-B cells. In the present work, the focus is on the concept of pre‑/pro-B cells as the cellular origin of MCC, which might also impact the understanding of other human small cell malignancies of unknown cellular origin, such as small cell carcinomas of the lung and other anatomical locations. In addition, this concept might pave the way for novel treatment options, especially for advanced MCC.

  16. Evolving Intelligent Systems Methodology and Applications

    CERN Document Server

    Angelov, Plamen; Kasabov, Nik

    2010-01-01

    From theory to techniques, the first all-in-one resource for EIS. There is a clear demand in advanced process industries, defense, and Internet and communication (VoIP) applications for intelligent yet adaptive/evolving systems. Evolving Intelligent Systems is the first self- contained volume that covers this newly established concept in its entirety, from a systematic methodology to case studies to industrial applications. Featuring chapters written by leading world experts, it addresses the progress, trends, and major achievements in this emerging research field, with a strong emphasis on th

  17. Dose concept of oncological hyperthermia: Heat-equation considering the cell destruction

    Directory of Open Access Journals (Sweden)

    Szasz A

    2006-01-01

    Full Text Available We shall assume, of course, that the objective of hyperthermia is to destroy the malignant cells. Destruction definitely needs energy. Description and quality assurance of hyperthermia use the Pennes heat equation to describe the processes. However the energy balance of the Pennes-equation does not contain the hyperthermic cell-destruction energy, which is a mandatory factor of the process. We propose a generalization of the Pennes-equation, inducing the entire energy balance. The new paradigm could be a theoretical basis of the till now empirical dose-construction for oncological hyperthermia. The cell destruction is a non-equilibrium thermodynamical process, described by the equations of chemical reactions. The dynamic behavior (time dependence has to be considered in this approach. We are going to define also a dose concept that can be objectively compared with other oncological methods. We show how such empirical dose as CEM43oC could be based theoretically as well.

  18. The epistemological and historical concept of nostoc from an indiciary lecture of George Canguilhem's "The cell theory"

    Directory of Open Access Journals (Sweden)

    Maurício de Carvalho Ramos

    2016-05-01

    Full Text Available Through an indiciary lecture of Canguilhem's article  "The cell theory", I propose, methodically guided by a epistemological-historical style research, the construction of the concept of nostoc as a metamorphic concept that integrated the concepts of primordial blastema and biblical slime of the French botanist Charles Naudin, set up a scientific culture of broad reach committed to solving the riddle of the morphological unity of organic and vital beings. The concept of Nostoc refers alchemically a gelatinous substance from the stars and endowed with balsamic medical virtues and botanically, a cianoficea algae of Nostoc genus. Examined the ideas of Canguilhem, Naudin, Jung and Paracelsus, this concept is proposed as a nucleoplasmatic oscillation, understood as a specific form of expression of the mythical-scientific theme of tension between continuity and discontinuity, as shown by Canguilhem in his history of cell concept.

  19. Support structure concept for integration of ITER diagnostics in the port cell

    Energy Technology Data Exchange (ETDEWEB)

    Udintsev, V.S., E-mail: victor.udintsev@iter.org [ITER Organization, Route de Vinon sur Verdon, 13115 St. Paul-Lez-Durance (France); Portalès, M.; Giacomin, T.; Darcourt, O.; Direz, M.-F.; Martins, J.P.; Penot, C.; Arumugam, A.P.; Drevon, J.-M.; Friconneau, J.P.; Levesy, B.; Maquet, P.; Patel, K.M.; Pitcher, C.S. [ITER Organization, Route de Vinon sur Verdon, 13115 St. Paul-Lez-Durance (France); Popova, E. [Russian Federation Domestic Agency, Moscow (Russian Federation); Proust, M. [ITER Organization, Route de Vinon sur Verdon, 13115 St. Paul-Lez-Durance (France); Ronden, D.M.S. [DIFFER, Nieuwegein (Netherlands); Walker, C.I.; Walsh, M.J.; Watts, C. [ITER Organization, Route de Vinon sur Verdon, 13115 St. Paul-Lez-Durance (France)

    2013-10-15

    Highlights: ► An interspace support structure to support the diagnostic systems from the back of the upper and equatorial port plugs to the biological shield plug. ► Port cell support structures are foreseen to handle the equipment in the port cell. ► Both ISS and PCSS will be supported by means of RH rail system. ► The structures will be positioned with a certain tolerance. ► The proposed concepts are found to fulfil the needs for support of the diagnostics in ITER. -- Abstract: Development of the diagnostics for ITER tokamak, which is presently under construction by several international partners at Cadarache in France, is a major challenge because of severe environment, strict engineering requirements, and the need for high reliability in the measurements. The diagnostic systems in the upper, equatorial and lower port cells on ITER are designed to be integrated within the interspace and port cell support structures. These structures are interfacing with remote handling rail system for the cask operations, thus facilitating the removal and installation of the diagnostics in the port and hence minimizing time for working close to the tokamak. In this paper, the challenges associated with the integration of the diagnostics in the port interspace and port cell, as well as their solutions will be addressed and presented. The interspace and the port cell support structures, as well as their interfaces with the biological shield, will be discussed.

  20. Performance evaluation of a proof-of-concept 70 W internal reforming methanol fuel cell system

    Science.gov (United States)

    Avgouropoulos, G.; Schlicker, S.; Schelhaas, K.-P.; Papavasiliou, J.; Papadimitriou, K. D.; Theodorakopoulou, E.; Gourdoupi, N.; Machocki, A.; Ioannides, T.; Kallitsis, J. K.; Kolb, G.; Neophytides, S.

    2016-03-01

    A proof-of-concept 70 W Internal Reforming Methanol Fuel Cell (IRMFC) stack including Balance-of-Plant (BoP) was designed, assembled and tested. Advent TPS® high-temperature, polymer electrolyte membrane electrode assemblies were employed for fuel cell operation at 200 °C. In order to avoid phosphoric acid poisoning of the reformer, the anode electrocatalyst of each cell was indirectly adjoined, via a separation plate, to a highly active CuMnAlOx catalyst coated onto copper foam, which served as methanol reforming layer. The reformer was in-situ converting the methanol/steam feed to the required hydrogen (internal reforming concept) at 200 °C, which was readily oxidized at the anode electrodes. The operation of the IRMFC was supported through a number of BoP components consisting of a start-up subsystem (air blower, evaporator and monolithic burner), a combined afterburner/evaporator device, methanol/water supply and data acquisition units (reactants/products analysis, temperature control, flow control, system load/output control). Depending on the composition of the liquid MeOH/H2O feed streams, current densities up to 0.18 A cm-2 and power output up to 70 W could be obtained with remarkable repeatability. Specific targets for improvement of the efficiency were identified.

  1. Evaluation of a Hydrogen Fuel Cell Powered Blended-Wing-Body Aircraft Concept for Reduced Noise and Emissions

    Science.gov (United States)

    Guynn, Mark D.; Freh, Joshua E.; Olson, Erik D.

    2004-01-01

    This report describes the analytical modeling and evaluation of an unconventional commercial transport aircraft concept designed to address aircraft noise and emission issues. A blended-wing-body configuration with advanced technology hydrogen fuel cell electric propulsion is considered. Predicted noise and emission characteristics are compared to a current technology conventional configuration designed for the same mission. The significant technology issues which have to be addressed to make this concept a viable alternative to current aircraft designs are discussed. This concept is one of the "Quiet Green Transport" aircraft concepts studied as part of NASA's Revolutionary Aerospace Systems Concepts (RASC) Program. The RASC Program was initiated to develop revolutionary concepts that address strategic objectives of the NASA Enterprises, such as reducing aircraft noise and emissions, and to identify advanced technology requirements for the concepts.

  2. Molecular biology of mycoplasmas: from the minimum cell concept to the artificial cell.

    Science.gov (United States)

    Cordova, Caio M M; Hoeltgebaum, Daniela L; Machado, Laís D P N; Santos, Larissa Dos

    2016-01-01

    Mycoplasmas are a large group of bacteria, sorted into different genera in the Mollicutes class, whose main characteristic in common, besides the small genome, is the absence of cell wall. They are considered cellular and molecular biology study models. We present an updated review of the molecular biology of these model microorganisms and the development of replicative vectors for the transformation of mycoplasmas. Synthetic biology studies inspired by these pioneering works became possible and won the attention of the mainstream media. For the first time, an artificial genome was synthesized (a minimal genome produced from consensus sequences obtained from mycoplasmas). For the first time, a functional artificial cell has been constructed by introducing a genome completely synthesized within a cell envelope of a mycoplasma obtained by transformation techniques. Therefore, this article offers an updated insight to the state of the art of these peculiar organisms' molecular biology.

  3. Biofabrication : reappraising the definition of an evolving field

    NARCIS (Netherlands)

    Groll, Jürgen; Boland, Thomas; Blunk, Torsten; Burdick, Jason A; Cho, Dong-Woo; Dalton, Paul D; Derby, Brian; Forgacs, Gabor; Li, Qing; Mironov, Vladimir A; Moroni, Lorenzo; Nakamura, Makoto; Shu, Wenmiao; Takeuchi, Shoji; Vozzi, Giovanni; Woodfield, Tim B F; Xu, Tao; Yoo, James J; Malda, Jos|info:eu-repo/dai/nl/412461099

    2016-01-01

    Biofabrication is an evolving research field that has recently received significant attention. In particular, the adoption of Biofabrication concepts within the field of Tissue Engineering and Regenerative Medicine has grown tremendously, and has been accompanied by a growing inconsistency in

  4. Biofabrication : Reappraising the definition of an evolving field

    NARCIS (Netherlands)

    Groll, Jürgen; Boland, Thomas; Blunk, Torsten; Burdick, Jason A.; Cho, Dong Woo; Dalton, Paul D.; Derby, Brian; Forgacs, Gabor; Li, Qing; Mironov, Vladimir A.; Moroni, Lorenzo; Nakamura, Makoto; Shu, Wenmiao; Takeuchi, Shoji; Vozzi, Giovanni; Woodfield, Tim B.F.; Xu, Tao; Yoo, James J.; Malda, Jos

    2016-01-01

    Biofabrication is an evolving research field that has recently received significant attention. In particular, the adoption of Biofabrication concepts within the field of Tissue Engineering and Regenerative Medicine has grown tremendously, and has been accompanied by a growing inconsistency in

  5. Cell design concepts for aqueous lithium-oxygen batteries: A model-based assessment

    Science.gov (United States)

    Grübl, Daniel; Bessler, Wolfgang G.

    2015-11-01

    Seven cell design concepts for aqueous (alkaline) lithium-oxygen batteries are investigated using a multi-physics continuum model for predicting cell behavior and performance in terms of the specific energy and specific power. Two different silver-based cathode designs (a gas diffusion electrode and a flooded cathode) and three different separator designs (a porous separator, a stirred separator chamber, and a redox-flow separator) are compared. Cathode and separator thicknesses are varied over a wide range (50 μm-20 mm) in order to identify optimum configurations. All designs show a considerable capacity-rate effect due to spatiotemporally inhomogeneous precipitation of solid discharge product LiOH·H2O. In addition, a cell design with flooded cathode and redox-flow separator including oxygen uptake within the external tank is suggested. For this design, the model predicts specific power up to 33 W/kg and specific energy up to 570 Wh/kg (gravimetric values of discharged cell including all cell components and catholyte except housing and piping).

  6. Advanced platelet-rich fibrin: a new concept for cell-based tissue engineering by means of inflammatory cells.

    Science.gov (United States)

    Ghanaati, Shahram; Booms, Patrick; Orlowska, Anna; Kubesch, Alica; Lorenz, Jonas; Rutkowski, Jim; Landes, Constantin; Sader, Robert; Kirkpatrick, Cj; Choukroun, Joseph

    2014-12-01

    Choukroun's platelet-rich fibrin (PRF) is obtained from blood without adding anticoagulants. In this study, protocols for standard platelet-rich fibrin (S-PRF) (2700 rpm, 12 minutes) and advanced platelet-rich fibrin (A-PRF) (1500 rpm, 14 minutes) were compared to establish by histological cell detection and histomorphometrical measurement of cell distribution the effects of the centrifugal force (speed and time) on the distribution of cells relevant for wound healing and tissue regeneration. Immunohistochemistry for monocytes, T and B -lymphocytes, neutrophilic granulocytes, CD34-positive stem cells, and platelets was performed on clots produced from four different human donors. Platelets were detected throughout the clot in both groups, although in the A-PRF group, more platelets were found in the distal part, away from the buffy coat (BC). T- and B-lymphocytes, stem cells, and monocytes were detected in the surroundings of the BC in both groups. Decreasing the rpm while increasing the centrifugation time in the A-PRF group gave an enhanced presence of neutrophilic granulocytes in the distal part of the clot. In the S-PRF group, neutrophils were found mostly at the red blood cell (RBC)-BC interface. Neutrophilic granulocytes contribute to monocyte differentiation into macrophages. Accordingly, a higher presence of these cells might be able to influence the differentiation of host macrophages and macrophages within the clot after implantation. Thus, A-PRF might influence bone and soft tissue regeneration, especially through the presence of monocytes/macrophages and their growth factors. The relevance and feasibility of this tissue-engineering concept have to be proven through in vivo studies.

  7. Evolving Procurement Organizations

    DEFF Research Database (Denmark)

    Bals, Lydia; Laiho, Aki; Laine, Jari

    Procurement has to find further levers and advance its contribution to corporate goals continuously. This places pressure on its organization in order to facilitate its performance. Therefore, Procurement organizations constantly have to evolve in order to match these demands. A conceptual model...... is presented and results of a first case study discussed. The findings highlight the importance of taking a contingency perspective on Procurement organization, understanding the internal and internal contingency factors. From a theoretical perspective, it opens up insights that can be furthermore leveraged...... in future studies in the fields of hybrid procurement organizations, global sourcing organizations as well as international procurement offices (IPOs). From a practical standpoint, an assessment of external and internal contingencies provides the opportunity to consciously match organization to its...

  8. Diffusion between evolving interfaces

    International Nuclear Information System (INIS)

    Juntunen, Janne; Merikoski, Juha

    2010-01-01

    Diffusion in an evolving environment is studied by continuous-time Monte Carlo simulations. Diffusion is modeled by continuous-time random walkers on a lattice, in a dynamic environment provided by bubbles between two one-dimensional interfaces driven symmetrically towards each other. For one-dimensional random walkers constrained by the interfaces, the bubble size distribution dominates diffusion. For two-dimensional random walkers, it is also controlled by the topography and dynamics of the interfaces. The results of the one-dimensional case are recovered in the limit where the interfaces are strongly driven. Even with simple hard-core repulsion between the interfaces and the particles, diffusion is found to depend strongly on the details of the dynamical rules of particles close to the interfaces.

  9. The evolving definition of systemic arterial hypertension.

    Science.gov (United States)

    Ram, C Venkata S; Giles, Thomas D

    2010-05-01

    Systemic hypertension is an important risk factor for premature cardiovascular disease. Hypertension also contributes to excessive morbidity and mortality. Whereas excellent therapeutic options are available to treat hypertension, there is an unsettled issue about the very definition of hypertension. At what level of blood pressure should we treat hypertension? Does the definition of hypertension change in the presence of co-morbid conditions? This article covers in detail the evolving concepts in the diagnosis and management of hypertension.

  10. The evolving epidemiology of inflammatory bowel disease.

    LENUS (Irish Health Repository)

    Shanahan, Fergus

    2009-07-01

    Epidemiologic studies in inflammatory bowel disease (IBD) include assessments of disease burden and evolving patterns of disease presentation. Although it is hoped that sound epidemiologic studies provide aetiological clues, traditional risk factor-based epidemiology has provided limited insights into either Crohn\\'s disease or ulcerative colitis etiopathogenesis. In this update, we will summarize how the changing epidemiology of IBD associated with modernization can be reconciled with current concepts of disease mechanisms and will discuss studies of clinically significant comorbidity in IBD.

  11. Modeling, simulation, and concept studies of a fuel cell hybrid electric vehicle powertrain

    Energy Technology Data Exchange (ETDEWEB)

    Oezbek, Markus

    2010-03-29

    This thesis focuses on the development of a fuel cell-based hybrid electric powertrain for smaller (2 kW) hybrid electric vehicles (HEVs). A Hardware-in-the-Loop test rig is designed and built with the possibility to simulate any load profile for HEVs in a realistic environment, whereby the environment is modeled. Detailed simulation models of the test rig are developed and validated to real physical components and control algorithms are designed for the DC/DC-converters and the fuel cell system. A state-feedback controller is developed for the DC/DC-converters where the state-space averaging method is used for the development. For the fuel cells, a gain-scheduling controller based on state feedback is developed and compared to two conventional methods. The design process of an HEV with regard to a given load profile is introduced with comparison between SuperCaps and batteries. The HEV is also evaluated with an introduction to different power management concepts with regard to fuel consumption, dynamics, and fuel cell deterioration rate. The power management methods are implemented in the test rig and compared. (orig.)

  12. Evolving to organizational learning.

    Science.gov (United States)

    Bechtold, B L

    2000-02-01

    To transform in stride with the business changes, organizations need to think of development as "organizational learning" rather than "training." Companies need to manage learning as a strategic competitive advantage for current and future business rather than as a perk for individuals. To position themselves for success in a dynamic business environment, companies need to reframe their concept of learning and development to a mindset of organizational learning.

  13. Why did heterospory evolve?

    Science.gov (United States)

    Petersen, Kurt B; Burd, Martin

    2017-08-01

    The primitive land plant life cycle featured the production of spores of unimodal size, a condition called homospory. The evolution of bimodal size distributions with small male spores and large female spores, known as heterospory, was an innovation that occurred repeatedly in the history of land plants. The importance of desiccation-resistant spores for colonization of the land is well known, but the adaptive value of heterospory has never been well established. It was an addition to a sexual life cycle that already involved male and female gametes. Its role as a precursor to the evolution of seeds has received much attention, but this is an evolutionary consequence of heterospory that cannot explain the transition from homospory to heterospory (and the lack of evolutionary reversal from heterospory to homospory). Enforced outcrossing of gametophytes has often been mentioned in connection to heterospory, but we review the shortcomings of this argument as an explanation of the selective advantage of heterospory. Few alternative arguments concerning the selective forces favouring heterospory have been proposed, a paucity of attention that is surprising given the importance of this innovation in land plant evolution. In this review we highlight two ideas that may lead us to a better understanding of why heterospory evolved. First, models of optimal resource allocation - an approach that has been used for decades in evolutionary ecology to help understand parental investment and other life-history patterns - suggest that an evolutionary increase in spore size could reach a threshold at which small spores yielding small, sperm-producing gametophytes would return greater fitness per unit of resource investment than would large spores and bisexual gametophytes. With the advent of such microspores, megaspores would evolve under frequency-dependent selection. This argument can account for the appearance of heterospory in the Devonian, when increasingly tall and complex

  14. Evolving a photosynthetic organelle

    Directory of Open Access Journals (Sweden)

    Nakayama Takuro

    2012-04-01

    Full Text Available Abstract The evolution of plastids from cyanobacteria is believed to represent a singularity in the history of life. The enigmatic amoeba Paulinella and its 'recently' acquired photosynthetic inclusions provide a fascinating system through which to gain fresh insight into how endosymbionts become organelles. The plastids, or chloroplasts, of algae and plants evolved from cyanobacteria by endosymbiosis. This landmark event conferred on eukaryotes the benefits of photosynthesis - the conversion of solar energy into chemical energy - and in so doing had a huge impact on the course of evolution and the climate of Earth 1. From the present state of plastids, however, it is difficult to trace the evolutionary steps involved in this momentous development, because all modern-day plastids have fully integrated into their hosts. Paulinella chromatophora is a unicellular eukaryote that bears photosynthetic entities called chromatophores that are derived from cyanobacteria and has thus received much attention as a possible example of an organism in the early stages of organellogenesis. Recent studies have unlocked the genomic secrets of its chromatophore 23 and provided concrete evidence that the Paulinella chromatophore is a bona fide photosynthetic organelle 4. The question is how Paulinella can help us to understand the process by which an endosymbiont is converted into an organelle.

  15. Fat: an evolving issue

    Directory of Open Access Journals (Sweden)

    John R. Speakman

    2012-09-01

    Work on obesity is evolving, and obesity is a consequence of our evolutionary history. In the space of 50 years, we have become an obese species. The reasons why can be addressed at a number of different levels. These include separating between whether the primary cause lies on the food intake or energy expenditure side of the energy balance equation, and determining how genetic and environmental effects contribute to weight variation between individuals. Opinion on whether increased food intake or decreased energy expenditure drives the obesity epidemic is still divided, but recent evidence favours the idea that food intake, rather than altered expenditure, is most important. There is more of a consensus that genetics explains most (probably around 65% of weight variation between individuals. Recent advances in genome-wide association studies have identified many polymorphisms that are linked to obesity, yet much of the genetic variance remains unexplained. Finding the causes of this unexplained variation will be an impetus of genetic and epigenetic research on obesity over the next decade. Many environmental factors – including gut microbiota, stress and endocrine disruptors – have been linked to the risk of developing obesity. A better understanding of gene-by-environment interactions will also be key to understanding obesity in the years to come.

  16. Evolving a photosynthetic organelle.

    Science.gov (United States)

    Nakayama, Takuro; Archibald, John M

    2012-04-24

    The evolution of plastids from cyanobacteria is believed to represent a singularity in the history of life. The enigmatic amoeba Paulinella and its 'recently' acquired photosynthetic inclusions provide a fascinating system through which to gain fresh insight into how endosymbionts become organelles.The plastids, or chloroplasts, of algae and plants evolved from cyanobacteria by endosymbiosis. This landmark event conferred on eukaryotes the benefits of photosynthesis--the conversion of solar energy into chemical energy--and in so doing had a huge impact on the course of evolution and the climate of Earth 1. From the present state of plastids, however, it is difficult to trace the evolutionary steps involved in this momentous development, because all modern-day plastids have fully integrated into their hosts. Paulinella chromatophora is a unicellular eukaryote that bears photosynthetic entities called chromatophores that are derived from cyanobacteria and has thus received much attention as a possible example of an organism in the early stages of organellogenesis. Recent studies have unlocked the genomic secrets of its chromatophore 23 and provided concrete evidence that the Paulinella chromatophore is a bona fide photosynthetic organelle 4. The question is how Paulinella can help us to understand the process by which an endosymbiont is converted into an organelle.

  17. UKAEA'S evolving contract philosophy

    International Nuclear Information System (INIS)

    Nicol, R. D.

    2003-01-01

    The United Kingdom Atomic Energy Authority (UKAEA) has gone through fundamental change over the last ten years. At the heart of this change has been UKAEA's relationship with the contracting and supply market. This paper describes the way in which UKAEA actively developed the market to support the decommissioning programme, and how the approach to contracting has evolved as external pressures and demands have changed. UKAEA's pro-active approach to industry has greatly assisted the development of a healthy, competitive market for services supporting decommissioning in the UK. There have been difficult changes and many challenges along the way, and some retrenchment was necessary to meet regulatory requirements. Nevertheless, UKAEA has sustained a high level of competition - now measured in terms of competed spend as a proportion of competable spend - with annual out-turns consistently over 80%. The prime responsibility for market development will pass to the new Nuclear Decommissioning Authority (NDA) in 2005, as the owner, on behalf of the Government, of the UK's civil nuclear liabilities. The preparatory work for the NDA indicates that the principles established by UKAEA will be carried forward. (author)

  18. Evolving PSTN to NGN

    Science.gov (United States)

    Wu, Liang T.

    2004-04-01

    The concept of Next Generation Network (NGN) was conceived around 1998 as an integrated solution to combine the quality and features of the PSTN with the low cost and routing flexibility of the Internet to provide a single infrastructure for the future public network. This carrier grade Internet solution calls for the creation of a consolidated, packet transport and switching infrastructure and the development of a flexible, open, software switch (softswitch) to handle voice telephony as well as multimedia services. Almost all the telecom equipment manufacturers as well as some Internet equipment vendors immediately subscribed to this vision and joined the race to create convergent products for the NGN market.

  19. 'It means everyone should know their status': exploring lay conceptions of sickle cell trait and sickle cell trait screening among African Americans within middle reproductive age.

    Science.gov (United States)

    Mayo-Gamble, Tilicia L; Barnes, Priscilla A; Cunningham Erves, Jennifer; Middlestadt, Susan E; Lin, Hsien-Chang

    2017-02-21

    This study examined the meaning of sickle cell trait and sickle cell trait screening from the lay perspective of African Americans. African Americans (N = 300), ages 18-35 and unaware of their sickle cell trait status, completed two open-ended questions from a larger survey. One question asked for their understanding of sickle cell trait; the other asked for their understanding of sickle cell trait screening. Content analysis occurred in two phases: (1) In vivo and holistic coding; and (2) focused coding. Four categories emerged illustrating lay conceptions of sickle cell trait; (1) Perceived as an illness; (2) Perceived recognition of the inheritance pattern of sickle cell trait; (3) Perceived lack of knowledge of sickle cell trait; and (4) Perceived importance of sickle cell trait. Five categories emerged illustrating lay conceptions for sickle cell trait screening: (1) Perceived recognition that screening means getting tested for sickle cell trait; (2) Perceived lack of knowledge of sickle cell trait screening; (3) Perceived health benefit of sickle cell trait screening; (4) Perceived importance of sickle cell trait screening; and (5) Perceived barriers to sickle cell trait screening. Sickle cell trait and sickle cell trait screening are concepts that are both regarded as important among this high-risk population. However, there is still misunderstanding concerning the hereditary nature and reproductive implications of sickle cell trait. Interventions seeking to improve communication on the need for sickle cell trait screening should begin by identifying what the population at large understands, knows and/or believes to improve their ability to make informed health decisions.

  20. Evolving expectations from international organisations

    International Nuclear Information System (INIS)

    Ruiz Lopez, C.

    2008-01-01

    The author stated that implementation of the geological disposal concept requires a strategy that provides national decision makers with sufficient confidence in the level of long-term safety and protection ultimately achieved. The concept of protection against harm has a broader meaning than radiological protection in terms of risk and dose. It includes the protection of the environment and socio-economic interests of communities. She recognised that a number of countries have established regulatory criteria already, and others are now discussing what constitutes a proper regulatory test and suitable time frame for judging the safety of long-term disposal. Each regulatory programme seeks to define reasonable tests of repository performance, using protection criteria and safety approaches consistent with the culture, values and expectations of the citizens of the country concerned. This means that there are differences in how protection and safety are addressed in national approaches to regulation and in the bases used for that. However, as was recognised in the Cordoba Workshop, it would be important to reach a minimum level of consistency and be able to explain the differences. C. Ruiz-Lopez presented an overview of the development of international guidance from ICRP, IAEA and NEA from the Cordoba workshop up to now, and positions of independent National Advisory Bodies. The evolution of these guidelines over time demonstrates an evolving understanding of long-term implications, with the recognition that dose and risk constraints should not be seen as measures of detriment beyond a few hundred years, the emphasis on sound engineering practices, and the introduction of new concepts and approaches which take into account social and economical aspects (e.g. constrained optimisation, BAT, managerial principles). In its new recommendations, ICRP (draft 2006) recognizes. in particular, that decision making processes may depend on other societal concerns and considers

  1. Molecular Theory of the Living Cell Concepts, Molecular Mechanisms, and Biomedical Applications

    CERN Document Server

    Ji, Sungchul

    2012-01-01

    This book presents a comprehensive molecular theory of the living cell based on over thirty concepts, principles and laws imported from thermodynamics, statistical mechanics, quantum mechanics, chemical kinetics, informatics, computer science, linguistics, semiotics, and philosophy. The author formulates physically, chemically and enzymologically realistic molecular mechanisms to account for the basic living processes such as ligand-receptor interactions, protein folding, single-molecule enzymic catalysis, force-generating mechanisms in molecular motors, signal transduction, regulation of the genome-wide RNA metabolism, morphogenesis, the micro-macro coupling in coordination dynamics, the origin of life, and the mechanisms of biological evolution itself. Possible solutions to basic and practical problems facing contemporary biology and biomedical sciences have been suggested, including pharmacotheragnostics and personalized medicine.

  2. Effects of heat stress on production, somatic cell score and conception rate in Holsteins.

    Science.gov (United States)

    Hagiya, Koichi; Hayasaka, Kiyoshi; Yamazaki, Takeshi; Shirai, Tatsuo; Osawa, Takefumi; Terawaki, Yoshinori; Nagamine, Yoshitaka; Masuda, Yutaka; Suzuki, Mitsuyoshi

    2017-01-01

    We examined the effects of heat stress (HS) on production traits, somatic cell score (SCS) and conception rate at first insemination (CR) in Holsteins in Japan. We used a total of 228 242 records of milk, fat and protein yields, and SCS for the first three lactations, as well as of CR in heifers and in first- and second-lactation cows that had calved for the first time between 2000 and 2012. Records from 47 prefectural weather stations throughout Japan were used to calculate the temperature-humidity index (THI); areas were categorized into three regional groups: no HS (THI cows, CR was affected by the interaction between HS group and insemination month: with summer and early autumn insemination, there was a reduction in CR, and it was much larger in the mild- and moderate-HS groups than in the no-HS group. © 2016 Japanese Society of Animal Science.

  3. CMIP6 Data Citation of Evolving Data

    Directory of Open Access Journals (Sweden)

    Martina Stockhause

    2017-06-01

    Full Text Available Data citations have become widely accepted. Technical infrastructures as well as principles and recommendations for data citation are in place but best practices or guidelines for their implementation are not yet available. On the other hand, the scientific climate community requests early citations on evolving data for credit, e.g. for CMIP6 (Coupled Model Intercomparison Project Phase 6. The data citation concept for CMIP6 is presented. The main challenges lie in limited resources, a strict project timeline and the dependency on changes of the data dissemination infrastructure ESGF (Earth System Grid Federation to meet the data citation requirements. Therefore a pragmatic, flexible and extendible approach for the CMIP6 data citation service was developed, consisting of a citation for the full evolving data superset and a data cart approach for citing the concrete used data subset. This two citation approach can be implemented according to the RDA recommendations for evolving data. Because of resource constraints and missing project policies, the implementation of the second part of the citation concept is postponed to CMIP7.

  4. Tumor biology and cancer therapy – an evolving relationship

    Directory of Open Access Journals (Sweden)

    Lother Ulrike

    2009-08-01

    Full Text Available Abstract The aim of palliative chemotherapy is to increase survival whilst maintaining maximum quality of life for the individual concerned. Although we are still continuing to explore the optimum use of traditional chemotherapy agents, the introduction of targeted therapies has significantly broadened the therapeutic options. Interestingly, the results from current trials put the underlying biological concept often into a new, less favorable perspective. Recent data suggested that altered pathways underlie cancer, and not just altered genes. Thus, an effective therapeutic agent will sometimes have to target downstream parts of a signaling pathway or physiological effects rather than individual genes. In addition, over the past few years increasing evidence has suggested that solid tumors represent a very heterogeneous group of cells with different susceptibility to cancer therapy. Thus, since therapeutic concepts and pathophysiological understanding are continuously evolving a combination of current concepts in tumor therapy and tumor biology is needed. This review aims to present current problems of cancer therapy by highlighting exemplary results from recent clinical trials with colorectal and pancreatic cancer patients and to discuss the current understanding of the underlying reasons.

  5. The Causal-Compositional Concept of Information—Part II: Information through Fairness: How Does the Relationship between Information, Fairness and Language Evolve, Stimulate the Development of (New Computing Devices and Help to Move towards the Information Society

    Directory of Open Access Journals (Sweden)

    Gerhard Luhn

    2012-09-01

    Full Text Available We are moving towards the information society, and we need to overcome the discouraging perspective, which is caused by the false belief that our thoughts (and thereby also our acting represent a somehow externally existing world. Indeed, it is already a step forward to proclaim that there exists a somehow common world for all people. But if those internal forms of representation are primarily bound to the subject itself, then, consequently, anybody can argue for his or her view of the world as being the “right” one. Well, what is the exit strategy out of this dilemma? It is information; information as understood in its actual and potential dimension, in its identity of structure and meaning. Such an approach requires a deeper elaborated conceptual approach. The goal of this study is to show that such a concept is glued by the strong relationship between seemingly unrelated disciplines: physics, semantics (semiotics/cognition and computer science, and even poetry. But the terminus of information is nowadays discussed and elaborated in all those disciplines. Hence, there is no shortcut, no way around. The aim of this study is not even to show that those strong relationships exist. We will see within the same horizon that, based on such a concept, new kinds of computing systems are becoming possible. Nowadays energy consumption is becoming a major issue regarding computing systems. We will work towards an approach, which enables new devices consuming a minimum amount of energy and maximizing the performance at the same time. And within the same horizon it becomes possible to release the saved energy towards a new ethical spirit—towards the information society.

  6. Stereotactic radiotherapy for non-small cell lung cancer: From concept to clinical reality. 2011 update

    International Nuclear Information System (INIS)

    Girard, N.; Mornex, F.

    2011-01-01

    Only 60% of patients with early-stage non-small cell lung cancer (NSCLC), a priori bearing a favorable prognosis, undergo radical resection because of the very frequent co-morbidities occurring in smokers, precluding surgery to be safely performed. Stereotactic radiotherapy consists of the use of multiple radiation micro-beams, allowing high doses of radiation to be delivered to the tumour (ranging from 7.5 to 20 Gy per fraction) in a small number of fractions (one to eight on average). Several studies with long-term follow-up are now available, showing the effectiveness of stereotactic radiotherapy to control stage I/II non-small cell lung cancer in medically inoperable patients. Local control rates are consistently reported to be above 95% with a median survival of 34 to 45 months. Because of these excellent results, stereotactic radiation therapy is now being evaluated in operable patients in several randomized trials with a surgical arm. Ultimately, the efficacy of stereotactic radiotherapy in early-stage tumours leads to hypothesize that it may represent an opportunity for locally-advanced tumors. The specific toxicities of stereotactic radiotherapy mostly correspond to radiation-induced chest wall side effects, especially for peripheral tumours. The use of adapted fractionation schemes has made feasible the use of stereotactic radiotherapy to treat proximal tumours. Overall, from a technical concept to the availability of specific treatment devices and the publication of clinical results, stereotactic radiotherapy represents a model of implementation in thoracic oncology. (authors)

  7. Disgust: Evolved function and structure

    NARCIS (Netherlands)

    Tybur, J.M.; Lieberman, D.; Kurzban, R.; DeScioli, P.

    2013-01-01

    Interest in and research on disgust has surged over the past few decades. The field, however, still lacks a coherent theoretical framework for understanding the evolved function or functions of disgust. Here we present such a framework, emphasizing 2 levels of analysis: that of evolved function and

  8. Natural selection promotes antigenic evolvability

    NARCIS (Netherlands)

    Graves, C.J.; Ros, V.I.D.; Stevenson, B.; Sniegowski, P.D.; Brisson, D.

    2013-01-01

    The hypothesis that evolvability - the capacity to evolve by natural selection - is itself the object of natural selection is highly intriguing but remains controversial due in large part to a paucity of direct experimental evidence. The antigenic variation mechanisms of microbial pathogens provide

  9. EVOLVE : International Conference

    CERN Document Server

    Deutz, Andre; Schuetze, Oliver; Bäck, Thomas; Tantar, Emilia; Tantar, Alexandru-Adrian; Moral, Pierre; Legrand, Pierrick; Bouvry, Pascal; Coello, Carlos

    2013-01-01

    Numerical and computational methods are nowadays used in a wide range of contexts in complex systems research, biology, physics, and engineering.  Over the last decades different methodological schools have emerged with emphasis on different aspects of computation, such as nature-inspired algorithms, set oriented numerics, probabilistic systems and Monte Carlo methods. Due to the use of different terminologies and emphasis on different aspects of algorithmic performance there is a strong need for a more integrated view and opportunities for cross-fertilization across particular disciplines. These proceedings feature 20 original publications from distinguished authors in the cross-section of computational sciences, such as machine learning algorithms and probabilistic models, complex networks and fitness landscape analysis, set oriented numerics and cell mapping, evolutionary multiobjective optimization, diversity-oriented search, and the foundations of genetic programming algorithms. By presenting cutting ed...

  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

    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...... mesenchymal stromal cells, unless there is proof that they exhibit the fundamental in vivo characteristics of pluripotency and the ability to self-renew. That said, these cells from various tissues hold great promise for therapeutic use in horses. The 3 components of tissue engineering - cells, biological...... factors, and biomaterials - are increasingly being applied in equine medicine, fuelled by better scaffolds and increased understanding of individual biofactors and cell sources.The effectiveness of stem cell-based therapies and most tissue engineering concepts has not been demonstrated sufficiently...

  11. 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.…

  12. A small molecule (pluripotin as a tool for studying cancer stem cell biology: proof of concept.

    Directory of Open Access Journals (Sweden)

    Susan D Mertins

    Full Text Available BACKGROUND: Cancer stem cells (CSC are thought to be responsible for tumor maintenance and heterogeneity. Bona fide CSC purified from tumor biopsies are limited in supply and this hampers study of CSC biology. Furthermore, purified stem-like CSC subpopulations from existing tumor lines are unstable in culture. Finding a means to overcome these technical challenges would be a useful goal. In a first effort towards this, we examined whether a chemical probe that promotes survival of murine embryonic stem cells without added exogenous factors can alter functional characteristics in extant tumor lines in a fashion consistent with a CSC phenotype. METHODOLOGY/PRINCIPAL FINDINGS: The seven tumor lines of the NCI60 colon subpanel were exposed to SC-1 (pluripotin, a dual kinase and GTPase inhibitor that promotes self-renewal, and then examined for tumorigenicity under limiting dilution conditions and clonogenic activity in soft agar. A statistically significant increase in tumor formation following SC-1 treatment was observed (p<0.04. Cloning efficiencies and expression of putative CSC surface antigens (CD133 and CD44 were also increased. SC-1 treatment led to sphere formation in some colon tumor lines. Finally, SC-1 inhibited in vitro kinase activity of RSK2, and another RSK2 inhibitor increased colony formation implicating a role for this kinase in eliciting a CSC phenotype. CONCLUSIONS/SIGNIFICANCE: These findings validate a proof of concept study exposure of extant tumor lines to a small molecule may provide a tractable in vitro model for understanding CSC biology.

  13. Concept for a solid-state multi-parameter sensor system for cell-culture monitoring

    International Nuclear Information System (INIS)

    Baecker, M.; Beging, S.; Biselli, M.; Poghossian, A.; Wang, J.; Zang, W.; Wagner, P.; Schoening, M.J.

    2009-01-01

    In this study, a concept for a silicon-based modular solid-state sensor system for inline multi-parameter monitoring of cell-culture fermentation processes is presented. The envisaged multi-parameter sensor system consists of two identical sensor modules and is intended for continuous quantification of up to five (bio-)chemical and physical parameters, namely, glucose and glutamine concentration, pH value, electrolyte conductivity and temperature by applying different transducer principles and/or different operation modes. Experimental results for the field-effect electrolyte-insulator-semiconductor (EIS) sterilisable pH sensor and electrolyte conductivity sensor based on interdigitated electrodes are presented. The ongoing autoclaving does not have any significant impact on the pH-sensitive properties of a Ta 2 O 5 -gate EIS sensor. Even after 30 autoclaving cycles, the pH sensors show a clear pH response and nearly linear calibration curve with a slope of 57 ± 1 mV/pH. Additional scanning electron microscopy and ellipsometric investigations do not show any visible surface degradation or changes in the thickness of the pH-sensitive Ta 2 O 5 layer. The preliminary results demonstrate the suitability of the developed EIS sensor for an inline pH measurement during a fermentation process. In addition, interdigitated electrodes of different geometries serving as electrolyte conductivity sensor have been tested for measurements in relatively high ionic-strength solutions.

  14. Autologous Bone Marrow Mononuclear Cell Therapy for Autism: An Open Label Proof of Concept Study

    Directory of Open Access Journals (Sweden)

    Alok Sharma

    2013-01-01

    Full Text Available Cellular therapy is an emerging therapeutic modality with a great potential for the treatment of autism. Recent findings show that the major underlying pathogenetic mechanisms of autism are hypoperfusion and immune alterations in the brain. So conceptually, cellular therapy which facilitates counteractive processes of improving perfusion by angiogenesis and balancing inflammation by immune regulation would exhibit beneficial clinical effects in patients with autism. This is an open label proof of concept study of autologous bone marrow mononuclear cells (BMMNCs intrathecal transplantation in 32 patients with autism followed by multidisciplinary therapies. All patients were followed up for 26 months (mean 12.7. Outcome measures used were ISAA, CGI, and FIM/Wee-FIM scales. Positron Emission Tomography-Computed Tomography (PET-CT scan recorded objective changes. Out of 32 patients, a total of 29 (91% patients improved on total ISAA scores and 20 patients (62% showed decreased severity on CGI-I. The difference between pre- and postscores was statistically significant (P<0.001 on Wilcoxon matched-pairs signed rank test. On CGI-II 96% of patients showed global improvement. The efficacy was measured on CGI-III efficacy index. Few adverse events including seizures in three patients were controlled with medications. The encouraging results of this leading clinical study provide future directions for application of cellular therapy in autism.

  15. Concept - or no concept

    DEFF Research Database (Denmark)

    Thorsteinsson, Uffe

    1999-01-01

    Discussion about concept in industrial companies. A method for mapping of managerial concept in specific area is shown......Discussion about concept in industrial companies. A method for mapping of managerial concept in specific area is shown...

  16. The non-flagellar type III secretion system evolved from the bacterial flagellum and diversified into host-cell adapted systems.

    Directory of Open Access Journals (Sweden)

    Sophie S Abby

    2012-09-01

    Full Text Available Type 3 secretion systems (T3SSs are essential components of two complex bacterial machineries: the flagellum, which drives cell motility, and the non-flagellar T3SS (NF-T3SS, which delivers effectors into eukaryotic cells. Yet the origin, specialization, and diversification of these machineries remained unclear. We developed computational tools to identify homologous components of the two systems and to discriminate between them. Our analysis of >1,000 genomes identified 921 T3SSs, including 222 NF-T3SSs. Phylogenomic and comparative analyses of these systems argue that the NF-T3SS arose from an exaptation of the flagellum, i.e. the recruitment of part of the flagellum structure for the evolution of the new protein delivery function. This reconstructed chronology of the exaptation process proceeded in at least two steps. An intermediate ancestral form of NF-T3SS, whose descendants still exist in Myxococcales, lacked elements that are essential for motility and included a subset of NF-T3SS features. We argue that this ancestral version was involved in protein translocation. A second major step in the evolution of NF-T3SSs occurred via recruitment of secretins to the NF-T3SS, an event that occurred at least three times from different systems. In rhizobiales, a partial homologous gene replacement of the secretin resulted in two genes of complementary function. Acquisition of a secretin was followed by the rapid adaptation of the resulting NF-T3SSs to multiple, distinct eukaryotic cell envelopes where they became key in parasitic and mutualistic associations between prokaryotes and eukaryotes. Our work elucidates major steps of the evolutionary scenario leading to extant NF-T3SSs. It demonstrates how molecular evolution can convert one complex molecular machine into a second, equally complex machine by successive deletions, innovations, and recruitment from other molecular systems.

  17. Light trapping in thin film solar cells using photonic engineering device concepts

    Science.gov (United States)

    Mutitu, James Gichuhi

    In this era of uncertainty concerning future energy solutions, strong reservations have arisen over the continued use and pursuit of fossil fuels and other conventional sources of energy. Moreover, there is currently a strong and global push for the implementation of stringent measures, in order to reduce the amount of green house gases emitted by every nation. As a consequence, there has emerged a sudden and frantic rush for new renewable energy solutions. In this world of renewable energy technologies is where we find photovoltaic (PV) technology today. However, as is, there are still many issues that need to be addressed before solar energy technologies become economically viable and available to all people, in every part of the world. This renewed interest in the development of solar electricity, has led to the advancement of new avenues that address the issues of cost and efficiency associated with PV. To this end, one of the prominent approaches being explored is thin film solar cell (TFSC) technology, which offers prospects of lower material costs and enables larger units of manufacture than conventional wafer based technology. However, TFSC technologies suffer from one major problem; they have lower efficiencies than conventional wafer based solar cell technologies. This lesser efficiency is based on a number of reasons, one of which is that with less material, there is less volume for the absorption of incident photons. This shortcoming leads to the need for optical light trapping; which is concerned with admitting the maximum amount of light into the solar cell and keeping the light within the structure for as long as possible. In this thesis, I present the fundamental scientific ideas, practice and methodology behind the application of photonic engineering device concepts to increase the light trapping capacity of thin film solar cells. In the introductory chapters, I develop the basic ideas behind light trapping in a sequential manner, where the effects

  18. Spacetimes containing slowly evolving horizons

    International Nuclear Information System (INIS)

    Kavanagh, William; Booth, Ivan

    2006-01-01

    Slowly evolving horizons are trapping horizons that are ''almost'' isolated horizons. This paper reviews their definition and discusses several spacetimes containing such structures. These include certain Vaidya and Tolman-Bondi solutions as well as (perturbatively) tidally distorted black holes. Taking into account the mass scales and orders of magnitude that arise in these calculations, we conjecture that slowly evolving horizons are the norm rather than the exception in astrophysical processes that involve stellar-scale black holes

  19. Natural selection promotes antigenic evolvability.

    Science.gov (United States)

    Graves, Christopher J; Ros, Vera I D; Stevenson, Brian; Sniegowski, Paul D; Brisson, Dustin

    2013-01-01

    The hypothesis that evolvability - the capacity to evolve by natural selection - is itself the object of natural selection is highly intriguing but remains controversial due in large part to a paucity of direct experimental evidence. The antigenic variation mechanisms of microbial pathogens provide an experimentally tractable system to test whether natural selection has favored mechanisms that increase evolvability. Many antigenic variation systems consist of paralogous unexpressed 'cassettes' that recombine into an expression site to rapidly alter the expressed protein. Importantly, the magnitude of antigenic change is a function of the genetic diversity among the unexpressed cassettes. Thus, evidence that selection favors among-cassette diversity is direct evidence that natural selection promotes antigenic evolvability. We used the Lyme disease bacterium, Borrelia burgdorferi, as a model to test the prediction that natural selection favors amino acid diversity among unexpressed vls cassettes and thereby promotes evolvability in a primary surface antigen, VlsE. The hypothesis that diversity among vls cassettes is favored by natural selection was supported in each B. burgdorferi strain analyzed using both classical (dN/dS ratios) and Bayesian population genetic analyses of genetic sequence data. This hypothesis was also supported by the conservation of highly mutable tandem-repeat structures across B. burgdorferi strains despite a near complete absence of sequence conservation. Diversification among vls cassettes due to natural selection and mutable repeat structures promotes long-term antigenic evolvability of VlsE. These findings provide a direct demonstration that molecular mechanisms that enhance evolvability of surface antigens are an evolutionary adaptation. The molecular evolutionary processes identified here can serve as a model for the evolution of antigenic evolvability in many pathogens which utilize similar strategies to establish chronic infections.

  20. Natural selection promotes antigenic evolvability.

    Directory of Open Access Journals (Sweden)

    Christopher J Graves

    Full Text Available The hypothesis that evolvability - the capacity to evolve by natural selection - is itself the object of natural selection is highly intriguing but remains controversial due in large part to a paucity of direct experimental evidence. The antigenic variation mechanisms of microbial pathogens provide an experimentally tractable system to test whether natural selection has favored mechanisms that increase evolvability. Many antigenic variation systems consist of paralogous unexpressed 'cassettes' that recombine into an expression site to rapidly alter the expressed protein. Importantly, the magnitude of antigenic change is a function of the genetic diversity among the unexpressed cassettes. Thus, evidence that selection favors among-cassette diversity is direct evidence that natural selection promotes antigenic evolvability. We used the Lyme disease bacterium, Borrelia burgdorferi, as a model to test the prediction that natural selection favors amino acid diversity among unexpressed vls cassettes and thereby promotes evolvability in a primary surface antigen, VlsE. The hypothesis that diversity among vls cassettes is favored by natural selection was supported in each B. burgdorferi strain analyzed using both classical (dN/dS ratios and Bayesian population genetic analyses of genetic sequence data. This hypothesis was also supported by the conservation of highly mutable tandem-repeat structures across B. burgdorferi strains despite a near complete absence of sequence conservation. Diversification among vls cassettes due to natural selection and mutable repeat structures promotes long-term antigenic evolvability of VlsE. These findings provide a direct demonstration that molecular mechanisms that enhance evolvability of surface antigens are an evolutionary adaptation. The molecular evolutionary processes identified here can serve as a model for the evolution of antigenic evolvability in many pathogens which utilize similar strategies to establish

  1. Initiator of carcinogenesis selectively and stably inhibits stem cell differentiation: a concept that initiation of carcinogenesis involves multiple phases

    International Nuclear Information System (INIS)

    Scott, R.E.; Maercklein, P.B.

    1985-01-01

    A concept of carcinogenesis was recently devised in our laboratory that suggests the development of defects in the control of cell differentiation is associated with an early phase of carcinogenesis. To test this proposal directly, the effects of an initiator of carcinogenesis (i.e., UV irradiation) on proadipocyte stem cell differentiation and proliferation was assayed. In this regard, 3T3 T proadipocytes represent a nontransformed mesenchymal stem cell line that possesses the ability to regulate its differentiation at a distinct state in the G 1 phase of the cell cycle as well as the ability to regulate its proliferation at two additional G 1 states. The results establish that a slow dosage of 254 nm UV irradiation selectivity and stably inhibits the differentiation of a high percentage of proadipocyte stem cells without significantly altering their ability to regulate cellular proliferation in growth factor-deficient or nutrient-deficient culture conditions. Differentiation-defect proadipocyte stem cells are demonstrated not to be completely transformed but to show an increased spontaneous transformation rate, as evidenced by the formation of type III foci in high density cell cultures. These data support the role of defects in the control of differentiation in the inhibition of carcinogenesis. These observations support a concept that the initiation of carcinogenesis involves multiple phases

  2. Robustness to Faults Promotes Evolvability: Insights from Evolving Digital Circuits.

    Science.gov (United States)

    Milano, Nicola; Nolfi, Stefano

    2016-01-01

    We demonstrate how the need to cope with operational faults enables evolving circuits to find more fit solutions. The analysis of the results obtained in different experimental conditions indicates that, in absence of faults, evolution tends to select circuits that are small and have low phenotypic variability and evolvability. The need to face operation faults, instead, drives evolution toward the selection of larger circuits that are truly robust with respect to genetic variations and that have a greater level of phenotypic variability and evolvability. Overall our results indicate that the need to cope with operation faults leads to the selection of circuits that have a greater probability to generate better circuits as a result of genetic variation with respect to a control condition in which circuits are not subjected to faults.

  3. Autoradiographic studies on the kinetics of fetal supporting cells and wall cells in rats 19 days after conception

    International Nuclear Information System (INIS)

    Lugani-Mehta, S.

    1980-01-01

    The duration of the S-phase of supporting cells and wall cells of rat fetuses aged 19 days was determined by the ''labelled mitosis'' method. The supporting cells are predecessors of the sertoli cells while the wall cells are predecessors of the boundary tissue and, possibly, of part of the peritubular Leydig cell system. The S-phase of the supporting cells was found to last 10.1 h while the S-phase of the wall cells lasted 9.2 h. The data were not in agreement with the data of other authors. (orig./MG) [de

  4. Parallel optical information, concept, and response evolver: POINCARE

    Science.gov (United States)

    Caulfield, H. John; Caulfield, Kimberly

    1991-08-01

    It is now possible to build a nonlinear adaptive system which will incorporate many of the properties of the human mind, such as true originality in such skills as reasoning by analogy and reasoning by retrodiction, including literally unpredictable thoughts; and development of individual styles, personalities, expertise, etc. Like humans, these optical processors will have a rich `subconscious'' experience. Like humans, they will be clonable, but clones will develop differently as they experience the world differently, make different decisions, develop different habits, etc. In short, powerful optical processors with some of the properties normally associated with human intelligence can be made. This approach can result in a powerful optical processor with those properties. A demonstration chosen for simplicity of implementation is suggested. This could be the first computer of any type which uses quantum indeterminacy in an integral and important way.

  5. Disordered gambling: the evolving concept of behavioral addiction

    Science.gov (United States)

    Clark, Luke

    2014-01-01

    The reclassification of gambling disorder within the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5) addictions category marks an important step for addiction science. The similarities between gambling disorder and the substance use disorders have been well documented. As gambling is unlikely to exert actively damaging effects on the brain, the cognitive sequelae of gambling disorder may provide insights into addictive vulnerabilities; this idea is critically evaluated in light of recent structural imaging data. The second part of the review analyzes a fundamental question of how a behavior can become addictive in the absence of exogenous drug stimulation. The relative potency of drug and nondrug rewards is considered, alongside evidence that cognitive distortions in the processing of chance (for example, the illusion of control and the gambler's fallacy) may constitute an important added ingredient in gambling. Further understanding of these mechanisms at neural and behavioral levels will be critical for the classification of future behavioral addictions, and I consider the current research data for obesity and binge eating, compulsive shopping, and internet gaming disorder. PMID:25336388

  6. Evolving concepts in the treatment of relapsing multiple sclerosis

    DEFF Research Database (Denmark)

    Comi, Giancarlo; Radaelli, Marta; Soelberg Sørensen, Per

    2017-01-01

    In the past 20 years the treatment scenario of multiple sclerosis has radically changed. The increasing availability of effective disease-modifying therapies has shifted the aim of therapeutic interventions from a reduction in relapses and disability accrual, to the absence of any sign of clinical...... or MRI activity. The choice for therapy is increasingly complex and should be driven by an appropriate knowledge of the mechanisms of action of the different drugs and of their risk-benefit profile. Because the relapsing phase of the disease is characterised by inflammation, treatment should be started...... as early as possible and aim to re-establish the normal complex interactions in the immune system. Before starting a treatment, neurologists should carefully consider the state of the disease, its prognostic factors and comorbidities, the patient's response to previous treatments, and whether the patient...

  7. The Chinese Air Force: Evolving Concepts, Roles, and Capabilities

    Science.gov (United States)

    2012-01-01

    improvements were for the most part cosmetic (the lengthening of a fuselage, relocation of components, etc.) and though Chinese writings are...Security Developments Involving the PRC, 62. 10 Chris Pocock with Clarence Fu, The Black Bats: CIA Spy Flights over China from Taiwan (Atglen, PA...development, 276 to avoid R&D investments, 277 RF–100A, 74 RF–84F, 74 RF–86A/F, 74 Rice , Donald, 19 Right Sizing the People’s Liberation Army: Exploring the

  8. Evolving concepts in staging and treatment of colorectal cancer

    NARCIS (Netherlands)

    Sloothaak, D.A.M.

    2015-01-01

    For localized colorectal cancer (CRC), lymph node metastases are the most powerful prognostic factor for disease specific and overall survival. In the first part of the thesis, we explore the prognostic role of lymph nodes in patients with stage I/II colon cancer. In these patients, nodal metastases

  9. Evolving Concepts of Pulmonary Hypertension Secondary to Left Heart Disease.

    Science.gov (United States)

    Ramu, Bhavadharini; Thenappan, Thenappan

    2016-04-01

    Pulmonary hypertension associated with left heart disease is the most common form of pulmonary hypertension. Although its pathophysiology remains incompletely understood, it is now well recognized that the presence of pulmonary hypertension is associated with a worse prognosis. Right ventricular failure has independent and additive prognostic value over pulmonary hypertension for adverse outcomes in left heart disease. Recently, several new terminologies have been introduced to better define and characterize the nature and severity of pulmonary hypertension. Several new treatment options including the use of pulmonary arterial hypertension specific therapies are being considered, but there is lack of evidence. Here, we review the recent advances in this field and summarize the diagnostic and therapeutic modalities of use in the management of pulmonary hypertension associated with left heart disease.

  10. Enrichment of circulating tumor cells from a large blood volume using leukapheresis and elutriation: proof of concept.

    Science.gov (United States)

    Eifler, Robert L; Lind, Judith; Falkenhagen, Dieter; Weber, Viktoria; Fischer, Michael B; Zeillinger, Robert

    2011-03-01

    The aim of this study was to determine the applicability of a sequential process using leukapheresis, elutriation, and fluorescence-activated cell sorting (FACS) to enrich and isolate circulating tumor cells from a large blood volume to allow further molecular analysis. Mononuclear cells were collected from 10 L of blood by leukapheresis, to which carboxyfluorescein succinimidyl ester prelabeled CaOV-3 tumor cells were spiked at a ratio of 26 to 10⁶ leukocytes. Elutriation separated the spiked leukapheresates primarily by cell size into distinct fractions, and leukocytes and tumor cells, characterized as carboxyfluorescein succinimidyl ester positive, EpCAM positive and CD45 negative events, were quantified by flow cytometry. Tumor cells were isolated from the last fraction using FACS or anti-EpCAM coupled immunomagnetic beads, and their recovery and purity determined by fluorescent microscopy and real-time PCR. Leukapheresis collected 13.5 x 10⁹ mononuclear cells with 87% efficiency. In total, 53 to 78% of spiked tumor cells were pre-enriched in the last elutriation fraction among 1.6 x 10⁹ monocytes. Flow cytometry predicted a circulating tumor cell purity of ~90% giving an enrichment of 100,000-fold following leukapheresis, elutriation, and FACS, where CaOV-3 cells were identified as EpCAM positive and CD45 negative events. FACS confirmed this purity. Alternatively, immunomagnetic bead adsorption recovered 10% of tumor cells with a median purity of 3.5%. This proof of concept study demonstrated that elutriation and FACS following leukapheresis are able to enrich and isolate tumor cells from a large blood volume for molecular characterization. Copyright © 2010 International Clinical Cytometry Society.

  11. Machine Learning Optimization of Evolvable Artificial Cells

    DEFF Research Database (Denmark)

    Caschera, F.; Rasmussen, S.; Hanczyc, M.

    2011-01-01

    can be explored. A machine learning approach (Evo-DoE) could be applied to explore this experimental space and define optimal interactions according to a specific fitness function. Herein an implementation of an evolutionary design of experiments to optimize chemical and biochemical systems based...... on a machine learning process is presented. The optimization proceeds over generations of experiments in iterative loop until optimal compositions are discovered. The fitness function is experimentally measured every time the loop is closed. Two examples of complex systems, namely a liposomal drug formulation...

  12. Applicability of the tissue stem cell turnover concept on the validity of cumulative dose based radiation risk evaluation

    International Nuclear Information System (INIS)

    Otsuka, Kensuke; Hamada, Nobuyuki; Iwasaki, Toshiyasu; Yoshida, Kazuo

    2011-01-01

    The radiation protection system adopts the linear no-threshold model to achieve proper radiation protection for considering cancer risks resulting from radiation exposure. This model uses cumulative dose to a tissue for risk evaluation in which cumulative dose is related to the amount of DNA damage and consequential induction of gene mutation. In this concept, gene mutation accumulates in tissue stem cells, the putative target of carcinogenesis, with total dose given to the tissue. Unlike high-dose-rate exposure, epidemiological studies in high radiation background areas, such as Kerala in India, revealed that cancer risks is not elevated by the dose to the inhabitants, suggesting that there exists some mechanisms to eliminate the damage/mutation in the exposed tissue under extremely low-dose-rate exposure situations. In this report, the dynamics of tissue stem cell turnover is evaluated as a possible mechanism under extremely low-dose-rate exposure situations. To this end, we reviewed recent literatures studying tissue stem cell turnover, and found that great advances in stem cell research have made it possible to trace a fate of stem cells in tissues. Furthermore, turnover of tissue stem cells is found to occur after irradiation, due to competition of stem cells within tissues. This raises a possibility that radiation effects may not accumulate in a tissue depending on the dose-rate and duration of exposure period. (author)

  13. Embodied Germ Cell at Work: Building an Expansive Concept of Physical Mobility in Home Care

    Science.gov (United States)

    Engestrom, Yrjo; Nummijoki, Jaana; Sannino, Annalisa

    2012-01-01

    This article presents a process of collective formation of a new concept of mobility between home care workers and their elderly clients, who are at risk of losing physical mobility and functional capacity. A new tool called mobility agreement was introduced to facilitate the inclusion of regular mobility exercises in home care visits and in the…

  14. Concept of Quantum Geometry in Optoelectronic Processes in Solids: Application to Solar Cells.

    Science.gov (United States)

    Nagaosa, Naoto; Morimoto, Takahiro

    2017-07-01

    The concept of topology is becoming more and more relevant to the properties and functions of electronic materials including various transport phenomena and optical responses. A pedagogical introduction is given here to the basic ideas and their applications to optoelectronic processes in solids. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  15. Development of a thin film solar cell interconnect for the PowerSphere concept

    International Nuclear Information System (INIS)

    Simburger, Edward J.; Matsumoto, James H.; Giants, Thomas W.; Garcia, Alexander; Liu, Simon; Rawal, Suraj P.; Perry, Alan R.; Marshall, Craig H.; Lin, John K.; Scarborough, Stephen E.; Curtis, Henry B.; Kerslake, Thomas W.; Peterson, Todd T.

    2005-01-01

    Progressive development of microsatellite technologies has resulted in increased demand for lightweight electrical power subsystems including solar arrays. The use of thin film photovoltaics has been recognized as a key solution to meet the power needs. The lightweight cells can generate sufficient power and still meet critical mass requirements. Commercially available solar cells produced on lightweight substrates are being studied as an option to fulfill the power needs. The commercially available solar cells are relatively inexpensive and have a high payoff potential. Commercially available thin film solar cells are primarily being produced for terrestrial applications. The need to convert the solar cell from a terrestrial to a space compatible application is the primary challenge. Solar cell contacts, grids and interconnects need to be designed to be atomic oxygen resistant and withstand rapid thermal cycling environments. A mechanically robust solar cell interconnect is also required in order to withstand handling during fabrication and survive during launch. The need to produce the solar cell interconnects has been identified as a primary goal of the PowerSphere program and is the topic of this paper. Details of the trade study leading to the final design involving the solar cell wrap around contact, flex blanket, welding process, and frame will be presented at the conference

  16. New Method to Disaggregate and Analyze Single Isolated Helminthes Cells Using Flow Cytometry: Proof of Concept

    Directory of Open Access Journals (Sweden)

    Karen Nava-Castro

    2011-01-01

    Full Text Available In parasitology, particularly in helminthes studies, several methods have been used to look for the expression of specific molecules, such as RT-PCR, western blot, 2D-electrophoresis, and microscopy, among others. However, these methods require homogenization of the whole helminth parasite, preventing evaluation of individual cells or specific cell types in a given parasite tissue or organ. Also, the extremely high interaction between helminthes and host cells (particularly immune cells is an important point to be considered. It is really hard to obtain fresh parasites without host cell contamination. Then, it becomes crucial to determine that the analyzed proteins are exclusively from parasitic origin, and not a consequence of host cell contamination. Flow cytometry is a fluorescence-based technique used to evaluate the expression of extra-and intracellular proteins in different type cells, including protozoan parasites. It also allows the isolation and recovery of single-cell populations. Here, we describe a method to isolate and obtain purified helminthes cells.

  17. Stem cell-based treatments against stroke: observations from human proof-of-concept studies and considerations regarding clinical applicability

    Directory of Open Access Journals (Sweden)

    Thorsten Roland Doeppner

    2014-10-01

    Full Text Available Ischemic stroke remains a heavy burden for industrialized countries. The only causal therapy is the recanalization of occluded vessels via thrombolysis, which due to a narrow time window still can be offered only to a minority of patients. Since the majority of patients continues to exhibit neurological deficits even following successful thrombolysis, restorative therapies are urgently needed that promote brain remodeling and repair once stroke injury has occurred. Due to their unique properties of action, stem cell-based strategies gained increasing interest during recent years. Using various stroke models in both rodents and primates, the transplantation of stem cells, namely of bone marrow derived mesenchymal stem cells (MSCs or neural progenitor cells (NPCs, has been shown to promote neurological recovery most likely via indirect bystander actions. In view of promising observations, clinical proof-of-concept studies are currently under way, in which effects of stem and precursor cells are evaluated in human stroke patients. In this review we summarize already published studies, which due to the broad experience in other medical contexts mostly employed bone marrow-derived MSCs by means of intravenous transplantation. With the overall number of clinical trials limited in number, only a fraction of these studies used non-treated control groups, and only single studies were adequately blinded. Despite these limitations, first promising results justify the need for more elaborate clinical trials in order to make stem cell transplantation a success for stroke treatment in the future.

  18. Evolving phenotypic networks in silico.

    Science.gov (United States)

    François, Paul

    2014-11-01

    Evolved gene networks are constrained by natural selection. Their structures and functions are consequently far from being random, as exemplified by the multiple instances of parallel/convergent evolution. One can thus ask if features of actual gene networks can be recovered from evolutionary first principles. I review a method for in silico evolution of small models of gene networks aiming at performing predefined biological functions. I summarize the current implementation of the algorithm, insisting on the construction of a proper "fitness" function. I illustrate the approach on three examples: biochemical adaptation, ligand discrimination and vertebrate segmentation (somitogenesis). While the structure of the evolved networks is variable, dynamics of our evolved networks are usually constrained and present many similar features to actual gene networks, including properties that were not explicitly selected for. In silico evolution can thus be used to predict biological behaviours without a detailed knowledge of the mapping between genotype and phenotype. Copyright © 2014 The Author. Published by Elsevier Ltd.. All rights reserved.

  19. Ranking in evolving complex networks

    Science.gov (United States)

    Liao, Hao; Mariani, Manuel Sebastian; Medo, Matúš; Zhang, Yi-Cheng; Zhou, Ming-Yang

    2017-05-01

    Complex networks have emerged as a simple yet powerful framework to represent and analyze a wide range of complex systems. The problem of ranking the nodes and the edges in complex networks is critical for a broad range of real-world problems because it affects how we access online information and products, how success and talent are evaluated in human activities, and how scarce resources are allocated by companies and policymakers, among others. This calls for a deep understanding of how existing ranking algorithms perform, and which are their possible biases that may impair their effectiveness. Many popular ranking algorithms (such as Google's PageRank) are static in nature and, as a consequence, they exhibit important shortcomings when applied to real networks that rapidly evolve in time. At the same time, recent advances in the understanding and modeling of evolving networks have enabled the development of a wide and diverse range of ranking algorithms that take the temporal dimension into account. The aim of this review is to survey the existing ranking algorithms, both static and time-aware, and their applications to evolving networks. We emphasize both the impact of network evolution on well-established static algorithms and the benefits from including the temporal dimension for tasks such as prediction of network traffic, prediction of future links, and identification of significant nodes.

  20. Cell organisation in the colonic crypt: a theoretical comparison of the pedigree and niche concepts.

    Directory of Open Access Journals (Sweden)

    Richard C van der Wath

    Full Text Available The intestinal mucosa is a monolayer of rapidly self-renewing epithelial cells which is not only responsible for absorption of water and nutrients into the bloodstream but also acts as a protective barrier against harmful microbes entering the body. New functional epithelial cells are produced from stem cells, and their proliferating progeny. These stem cells are found within millions of crypts (tubular pits spaced along the intestinal tract. The entire intestinal epithelium is replaced every 2-3 days in mice (3-5 days in humans and hence cell production, differentiation, migration and turnover need to be tightly regulated. Malfunctions in this regulation are strongly linked to inflammatory bowel diseases and to the formation of adenomas and ultimately cancerous tumours. Despite a great deal of biological experimentation and observation, precisely how colonic crypts are regulated to produce mature colonocytes remains unclear. To assist in understanding how cell organisation in crypts is achieved, two very different conceptual models of cell behaviour are developed here, referred to as the 'pedigree' and the 'niche' models. The pedigree model proposes that crypt cells are largely preprogrammed and receive minimal prompting from the environment as they move through a routine of cell differentiation and proliferation to become mature colonocytes. The niche model proposes that crypt cells are primarily influenced by the local microenvironments along the crypt, and that predetermined cell behaviour plays a negligible role in their development. In this paper we present a computational model of colonic crypts in the mouse, which enables a comparison of the quality and controllability of mature coloncyte production by crypts operating under these two contrasting conceptual models of crypt regulation.

  1. Quantal concept of T-cell activation: adhesion domains as immunological synapses

    International Nuclear Information System (INIS)

    Sackmann, Erich

    2011-01-01

    Adhesion micro-domains (ADs) formed during encounters of lymphocytes with antigen-presenting cells (APC) mediate the genetic expression of quanta of cytokines interleukin-2 (IL-2). The IL-2-induced activation of IL-2 receptors promotes the stepwise progression of the T-cells through the cell cycle, hence their name, immunological synapses. The ADs form short-lived reaction centres controlling the recruitment of activators of the biochemical pathway (the kinases Lck and ZAP) while preventing the access of inhibitors (phosphatase CD45) through steric repulsion forces. CD45 acts as the generator of adhesion domains and, through its role as a spacer protein, also as the promoter of the reaction. In a second phase of T-cell-APC encounters, long-lived global reaction spaces (called supramolecular activation complexes (SMAC)) form by talin-mediated binding of the T-cell integrin (LFA-1) to the counter-receptor ICAM-1, resulting in the formation of ring-like tight adhesion zones (peripheral SMAC). The ADs move to the centre of the intercellular adhesion zone forming the central SMAC, which serve in the recycling of the AD. We propose that cell stimulation is triggered by integrating the effect evoked by the short-lived adhesion domains. Similar global reaction platforms are formed by killer cells to destruct APC. We present a testable mechanical model showing that global reaction spaces (SMAC or dome-like contacts between cytotoxic cells and APC) form by self-organization through delayed activation of the integrin-binding affinity and stabilization of the adhesion zones by F-actin recruitment. The mechanical stability and the polarization of the adhering T-cells are mediated by microtubule-actin cross-talk.

  2. Microlearning an Evolving Elearning Trend

    Directory of Open Access Journals (Sweden)

    Giurgiu Luminiţa

    2017-06-01

    Full Text Available This article is analyzing the meanings of the micro-learning trend, as they have emerged and developed over the last few years. Exploring how the term micro-learning is used to organize and order a set of pedagogical and technological phenomena and concepts in new and interesting ways, it is brought into focus the most popular and widely used learning management platforms that embrace this concept.

  3. Essentials of single-cell analysis concepts, applications and future prospects

    CERN Document Server

    Santra, Tuhin

    2016-01-01

    This book provides an overview of single-cell isolation, separation, injection, lysis and dynamics analysis as well as a study of their heterogeneity using different miniaturized devices. As an important part of single-cell analysis, different techniques including electroporation, microinjection, optical trapping, optoporation, rapid electrokinetic patterning and optoelectronic tweezers are described in detail. It presents different fluidic systems (e.g. continuous micro/nano-fluidic devices, microfluidic cytometry) and their integration with sensor technology, optical and hydrodynamic stretchers etc., and demonstrates the applications of single-cell analysis in systems biology, proteomics, genomics, epigenomics, cancer transcriptomics, metabolomics, biomedicine and drug delivery systems. It also discusses the future challenges for single-cell analysis, including the advantages and limitations. This book is enjoyable reading material while at the same time providing essential information to scientists in acad...

  4. Concept of rewritable organic ferroelectric random access memory in two lateral transistors-in-one cell architecture

    International Nuclear Information System (INIS)

    Kim, Min-Hoi; Lee, Gyu Jeong; Keum, Chang-Min; Lee, Sin-Doo

    2014-01-01

    We propose a concept of rewritable ferroelectric random access memory (RAM) with two lateral organic transistors-in-one cell architecture. Lateral integration of a paraelectric organic field-effect transistor (OFET), being a selection transistor, and a ferroelectric OFET as a memory transistor is realized using a paraelectric depolarizing layer (PDL) which is patterned on a ferroelectric insulator by transfer-printing. For the selection transistor, the key roles of the PDL are to reduce the dipolar strength and the surface roughness of the gate insulator, leading to the low memory on–off ratio and the high switching on–off current ratio. A new driving scheme preventing the crosstalk between adjacent memory cells is also demonstrated for the rewritable operation of the ferroelectric RAM. (paper)

  5. Cell Concepts of Metal-Sulfur Batteries (Metal = Li, Na, K, Mg): Strategies for Using Sulfur in Energy Storage Applications.

    Science.gov (United States)

    Medenbach, Lukas; Adelhelm, Philipp

    2017-09-29

    There is great interest in using sulfur as active component in rechargeable batteries thanks to its low cost and high specific charge (1672 mAh/g). The electrochemistry of sulfur, however, is complex and cell concepts are required, which differ from conventional designs. This review summarizes different strategies for utilizing sulfur in rechargeable batteries among membrane concepts, polysulfide concepts, all-solid-state concepts as well as high-temperature systems. Among the more popular lithium-sulfur and sodium-sulfur batteries, we also comment on recent results on potassium-sulfur and magnesium-sulfur batteries. Moreover, specific properties related to the type of light metal are discussed.

  6. Supercritical CO2 Foaming of Thermoplastic Materials Derived from Maize: Proof-of-Concept Use in Mammalian Cell Culture Applications

    Science.gov (United States)

    Trujillo-de Santiago, Grissel; Portales-Cabrera, Cynthia Guadalupe; Portillo-Lara, Roberto; Araiz-Hernández, Diana; Del Barone, Maria Cristina; García-López, Erika; Rojas-de Gante, Cecilia; de los Angeles De Santiago-Miramontes, María; Segoviano-Ramírez, Juan Carlos; García-Lara, Silverio; Rodríguez-González, Ciro Ángel; Alvarez, Mario Moisés; Di Maio, Ernesto; Iannace, Salvatore

    2015-01-01

    Background Foams are high porosity and low density materials. In nature, they are a common architecture. Some of their relevant technological applications include heat and sound insulation, lightweight materials, and tissue engineering scaffolds. Foams derived from natural polymers are particularly attractive for tissue culture due to their biodegradability and bio-compatibility. Here, the foaming potential of an extensive list of materials was assayed, including slabs elaborated from whole flour, the starch component only, or the protein fraction only of maize seeds. Methodology/Principal Findings We used supercritical CO2 to produce foams from thermoplasticized maize derived materials. Polyethylene-glycol, sorbitol/glycerol, or urea/formamide were used as plasticizers. We report expansion ratios, porosities, average pore sizes, pore morphologies, and pore size distributions for these materials. High porosity foams were obtained from zein thermoplasticized with polyethylene glycol, and from starch thermoplasticized with urea/formamide. Zein foams had a higher porosity than starch foams (88% and 85%, respectively) and a narrower and more evenly distributed pore size. Starch foams exhibited a wider span of pore sizes and a larger average pore size than zein (208.84 vs. 55.43 μm2, respectively). Proof-of-concept cell culture experiments confirmed that mouse fibroblasts (NIH 3T3) and two different prostate cancer cell lines (22RV1, DU145) attached to and proliferated on zein foams. Conclusions/Significance We conducted screening and proof-of-concept experiments on the fabrication of foams from cereal-based bioplastics. We propose that a key indicator of foamability is the strain at break of the materials to be foamed (as calculated from stress vs. strain rate curves). Zein foams exhibit attractive properties (average pore size, pore size distribution, and porosity) for cell culture applications; we were able to establish and sustain mammalian cell cultures on zein

  7. Supercritical CO2 foaming of thermoplastic materials derived from maize: proof-of-concept use in mammalian cell culture applications.

    Science.gov (United States)

    Trujillo-de Santiago, Grissel; Portales-Cabrera, Cynthia Guadalupe; Portillo-Lara, Roberto; Araiz-Hernández, Diana; Del Barone, Maria Cristina; García-López, Erika; Rojas-de Gante, Cecilia; de Los Angeles De Santiago-Miramontes, María; Segoviano-Ramírez, Juan Carlos; García-Lara, Silverio; Rodríguez-González, Ciro Ángel; Alvarez, Mario Moisés; Di Maio, Ernesto; Iannace, Salvatore

    2015-01-01

    Foams are high porosity and low density materials. In nature, they are a common architecture. Some of their relevant technological applications include heat and sound insulation, lightweight materials, and tissue engineering scaffolds. Foams derived from natural polymers are particularly attractive for tissue culture due to their biodegradability and bio-compatibility. Here, the foaming potential of an extensive list of materials was assayed, including slabs elaborated from whole flour, the starch component only, or the protein fraction only of maize seeds. We used supercritical CO2 to produce foams from thermoplasticized maize derived materials. Polyethylene-glycol, sorbitol/glycerol, or urea/formamide were used as plasticizers. We report expansion ratios, porosities, average pore sizes, pore morphologies, and pore size distributions for these materials. High porosity foams were obtained from zein thermoplasticized with polyethylene glycol, and from starch thermoplasticized with urea/formamide. Zein foams had a higher porosity than starch foams (88% and 85%, respectively) and a narrower and more evenly distributed pore size. Starch foams exhibited a wider span of pore sizes and a larger average pore size than zein (208.84 vs. 55.43 μm2, respectively). Proof-of-concept cell culture experiments confirmed that mouse fibroblasts (NIH 3T3) and two different prostate cancer cell lines (22RV1, DU145) attached to and proliferated on zein foams. We conducted screening and proof-of-concept experiments on the fabrication of foams from cereal-based bioplastics. We propose that a key indicator of foamability is the strain at break of the materials to be foamed (as calculated from stress vs. strain rate curves). Zein foams exhibit attractive properties (average pore size, pore size distribution, and porosity) for cell culture applications; we were able to establish and sustain mammalian cell cultures on zein foams for extended time periods.

  8. Supercritical CO2 foaming of thermoplastic materials derived from maize: proof-of-concept use in mammalian cell culture applications.

    Directory of Open Access Journals (Sweden)

    Grissel Trujillo-de Santiago

    Full Text Available Foams are high porosity and low density materials. In nature, they are a common architecture. Some of their relevant technological applications include heat and sound insulation, lightweight materials, and tissue engineering scaffolds. Foams derived from natural polymers are particularly attractive for tissue culture due to their biodegradability and bio-compatibility. Here, the foaming potential of an extensive list of materials was assayed, including slabs elaborated from whole flour, the starch component only, or the protein fraction only of maize seeds.We used supercritical CO2 to produce foams from thermoplasticized maize derived materials. Polyethylene-glycol, sorbitol/glycerol, or urea/formamide were used as plasticizers. We report expansion ratios, porosities, average pore sizes, pore morphologies, and pore size distributions for these materials. High porosity foams were obtained from zein thermoplasticized with polyethylene glycol, and from starch thermoplasticized with urea/formamide. Zein foams had a higher porosity than starch foams (88% and 85%, respectively and a narrower and more evenly distributed pore size. Starch foams exhibited a wider span of pore sizes and a larger average pore size than zein (208.84 vs. 55.43 μm2, respectively. Proof-of-concept cell culture experiments confirmed that mouse fibroblasts (NIH 3T3 and two different prostate cancer cell lines (22RV1, DU145 attached to and proliferated on zein foams.We conducted screening and proof-of-concept experiments on the fabrication of foams from cereal-based bioplastics. We propose that a key indicator of foamability is the strain at break of the materials to be foamed (as calculated from stress vs. strain rate curves. Zein foams exhibit attractive properties (average pore size, pore size distribution, and porosity for cell culture applications; we were able to establish and sustain mammalian cell cultures on zein foams for extended time periods.

  9. The 'E' factor -- evolving endodontics.

    Science.gov (United States)

    Hunter, M J

    2013-03-01

    Endodontics is a constantly developing field, with new instruments, preparation techniques and sealants competing with trusted and traditional approaches to tooth restoration. Thus general dental practitioners must question and understand the significance of these developments before adopting new practices. In view of this, the aim of this article, and the associated presentation at the 2013 British Dental Conference & Exhibition, is to provide an overview of endodontic methods and constantly evolving best practice. The presentation will review current preparation techniques, comparing rotary versus reciprocation, and question current trends in restoration of the endodontically treated tooth.

  10. Nucleoli cytomorphology in cutaneous melanoma cells - a new prognostic approach to an old concept.

    Science.gov (United States)

    Donizy, Piotr; Biecek, Przemyslaw; Halon, Agnieszka; Maciejczyk, Adam; Matkowski, Rafal

    2017-12-29

    The nucleolus is an organelle that is an ultrastructural element of the cell nucleus observed in H&E staining as a roundish body stained with eosin due to its high protein content. Changes in the nucleoli cytomorphology were one of the first histopathological characteristics of malignant tumors. The aim of this study was to assess the relationship between the cytomorphological characteristics of nucleoli and detailed clinicopathological parameters of melanoma patients. Moreover, we analyzed the correlation between cytomorphological parameters of nucleoli and immunoreactivity of selected proteins responsible for, among others, regulation of epithelial-mesenchymal transition (SPARC, N-cadherin), cell adhesion and motility (ALCAM, ADAM-10), mitotic divisions (PLK1), cellular survival (FOXP1) and the functioning of Golgi apparatus (GOLPH3, GP73). Three characteristics of nucleoli - presence, size and number - of cancer cells were assessed in H&E-stained slides of 96 formalin-fixed paraffin-embedded primary cutaneous melanoma tissue specimens. The results were correlated with classical clinicopathological features and patient survival. Immunohistochemical analysis of the above mentioned proteins was described in details in previous studies. Higher prevalence and size of nucleoli were associated with thicker and mitogenic tumors. All three nucleolar characteristics were related to the presence of ulceration. Moreover, microsatellitosis was strongly correlated with the presence of macronucleoli and polynucleolization (presence of two or more nucleoli). Lack of immunologic response manifested as no TILs in primary tumor was associated with high prevalence of melanoma cells with distinct nucleoli. Interestingly, in nodular melanoma a higher percentage of melanoma cells with prominent nucleoli was observed. In Kaplan-Meier analysis, increased prevalence and amount, but not size of nucleoli, were connected with shorter cancer-specific and disease-free survival. (1) High

  11. CNT Nanobombs for Specific Eradication of Cancer Cells: A New Concept in Cancer Theranosticss

    Directory of Open Access Journals (Sweden)

    Yadollah Omidi

    2011-11-01

    Full Text Available Whole extermination of cancerous cells/tissue seems no longer to be a dream. Exploiting advanced photoactive nanomaterials such as functionalized fullerenes and carbon nanotubes (CNTs can act as CNT nanobombs (CNT-NBs when exposed to the near infrared (NIR radiation. PEGylated CNTs tagged with an antibody/aptamer can target cancer cells. Once attached to cancer cells, the NIR emission (700-1100 nm, in which body tissues are mostly transparent, can be applied to CNT-NBs which can absorb the light and get heated up. The resultant enhanced temperature can abolish the cancer. Once stealth CNT-NBs are tagged with imaging moieties, it would be a matter of computer gaming for physician who can inject it for real time visualization and destruction of cancer by activation of the NIR laser. While, many nanosystems (NSs are still in waiting list for clinical translation, our dreams may come true by applying stealth CNT-NBs against cancer.

  12. Advanced nickel/hydrogen dependent pressure vessel (DPV) cell and battery concepts

    Energy Technology Data Exchange (ETDEWEB)

    Caldwell, D.B. [Technologies Div., Eagle Picher Industries, Inc., Joplin, MO (United States); Fox, C.L. [Technologies Div., Eagle Picher Industries, Inc., Joplin, MO (United States); Miller, L.E. [Technologies Div., Eagle Picher Industries, Inc., Joplin, MO (United States)

    1997-03-01

    The dependent pressure vessel (DPV) nickel/hydrogen (NiH{sub 2}) design is being developed by Eagle-Picher industries, Inc. (EPI) as an advanced battery for military and commercial aerospace and terrestrial applications. The DPV cell design offers high specific energy and energy density as well as reduced cost, while retaining the established individual pressure vessel (IPV) technology, flight heritage and database. This advanced DPV design also offers a more efficient mechanical, electrical and thermal cell and battery configuration and a reduced parts count. The DPV battery design promotes compact, minimum volume packaging and weight efficiency, and delivers cost and weight savings with minimal design risks. (orig.)

  13. Hierarchical imaging: a new concept for targeted imaging of large volumes from cells to tissues.

    Science.gov (United States)

    Wacker, Irene; Spomer, Waldemar; Hofmann, Andreas; Thaler, Marlene; Hillmer, Stefan; Gengenbach, Ulrich; Schröder, Rasmus R

    2016-12-12

    Imaging large volumes such as entire cells or small model organisms at nanoscale resolution seemed an unrealistic, rather tedious task so far. Now, technical advances have lead to several electron microscopy (EM) large volume imaging techniques. One is array tomography, where ribbons of ultrathin serial sections are deposited on solid substrates like silicon wafers or glass coverslips. To ensure reliable retrieval of multiple ribbons from the boat of a diamond knife we introduce a substrate holder with 7 axes of translation or rotation specifically designed for that purpose. With this device we are able to deposit hundreds of sections in an ordered way in an area of 22 × 22 mm, the size of a coverslip. Imaging such arrays in a standard wide field fluorescence microscope produces reconstructions with 200 nm lateral resolution and 100 nm (the section thickness) resolution in z. By hierarchical imaging cascades in the scanning electron microscope (SEM), using a new software platform, we can address volumes from single cells to complete organs. In our first example, a cell population isolated from zebrafish spleen, we characterize different cell types according to their organelle inventory by segmenting 3D reconstructions of complete cells imaged with nanoscale resolution. In addition, by screening large numbers of cells at decreased resolution we can define the percentage at which different cell types are present in our preparation. With the second example, the root tip of cress, we illustrate how combining information from intermediate resolution data with high resolution data from selected regions of interest can drastically reduce the amount of data that has to be recorded. By imaging only the interesting parts of a sample considerably less data need to be stored, handled and eventually analysed. Our custom-designed substrate holder allows reproducible generation of section libraries, which can then be imaged in a hierarchical way. We demonstrate, that EM

  14. Mean inactivation dose: a useful concept for intercomparison of human cell survival curves

    International Nuclear Information System (INIS)

    Fertil, B.; Dertinger, H.; Courdi, A.; Malaise, E.P.

    1984-01-01

    The mean inactivation dose (anti D) is calculated for published in vitro survival curves obtained from cell lines of both normal and neoplastic human tissues. Cells belonging to different histological categories (melanomas, carcinomas, etc.) are shown to be characterized by distinct values of anti D which are related to the clinical radiosensitivity of tumors from these categories. Compared to other ways of representing in vitro radiosensitivity, e.g., by the multitarget parameters D 8 and n, the parameter anti D has several specific advantages

  15. Evolving Systems: An Outcome of Fondest Hopes and Wildest Dreams

    Science.gov (United States)

    Frost, Susan A.; Balas, Mark J.

    2012-01-01

    New theory is presented for evolving systems, which are autonomously controlled subsystems that self-assemble into a new evolved system with a higher purpose. Evolving systems of aerospace structures often require additional control when assembling to maintain stability during the entire evolution process. This is the concept of Adaptive Key Component Control that operates through one specific component to maintain stability during the evolution. In addition, this control must often overcome persistent disturbances that occur while the evolution is in progress. Theoretical results will be presented for Adaptive Key Component control for persistent disturbance rejection. An illustrative example will demonstrate the Adaptive Key Component controller on a system composed of rigid body and flexible body modes.

  16. Targeted siRNA Delivery to Diseased Microvascular Endothelial Cells-Cellular and Molecular Concepts

    NARCIS (Netherlands)

    Kowalski, Piotr S.; Leus, Niek G. J.; Scherphof, Gerrit L.; Ruiters, Marcel H. J.; Kamps, Jan A. A. M.; Molema, Grietje

    Increased insight in the role of endothelial cells in the pathophysiology of cancer, inflammatory and cardiovascular diseases, has drawn great interest in pharmacological interventions aiming at the endothelium in diseased sites. Their location in the body makes them suitable targets for therapeutic

  17. Laboratory: Undergraduate Laboratory Experiment Teaching Fundamental Concepts of Rheology in Context of Sickle Cell Anemia

    Science.gov (United States)

    Vernengo, Jennifer; Purdy, Caitlin; Farrell, Stephanie

    2014-01-01

    This paper describes a biomedical engineering experiment that introduces students to rheology. Healthy and sickle-cell blood analogs are prepared that are composed of chitosan particles suspended in aqueous glycerol solutions, which substitute for RBCs and plasma, respectively. Students study flow properties of the blood analogs with a viscometer…

  18. Oxygen-hydrogen fuel cell with an iodine-iodide cathode - A concept

    Science.gov (United States)

    Javet, P.

    1970-01-01

    Fuel cell uses a porous cathode through which is fed a solution of iodine in aqueous iodide solution, the anode is a hydrogen electrode. No activation polarization appears on the cathode because of the high exchange-current density of the iodine-iodide electrode.

  19. The concept of transcortical cell assemblies: a key to the understanding of cortical lateralization and interhemispheric interaction.

    Science.gov (United States)

    Pulvermüller, F; Mohr, B

    1996-01-01

    According to Hebb, elements of higher cognitive processes, such as concepts, words and mental images, are realized in the brain as cortical cell assemblies, i.e. large and strongly connected neuron populations that form functional units. Neurons belonging to such assemblies may be scattered over wide cortical areas, and some cell assemblies may even comprise neurons of both hemispheres (transcortical assemblies). If full activation (ignition) of an assembly leads to fast circulation of neuronal activity in the assembly, this process should be visible in high-frequency cortical responses. Some evidence will be reviewed that cell assembly ignition indeed leads to changes in high-frequency cortical responses which can be recorded in the EEG and MEG. Within the cell assembly-framework, the question of cortical laterality translates into the question of how neurons of transcortical assemblies are balanced between the hemispheres. This approach allows for different degrees of laterality. Recent evidence is summarized that the degree of laterality indeed differs between language units. For example, the cortical representation of certain words appears to be strongly lateralized to the left hemisphere while those of others are less lateralized. If neurons of both hemispheres are part of one assembly bihemispheric processing should lead to a processing advantage compared to processing in the dominant hemisphere alone. The latter appears to be the case for lexical processing, as revealed by recent behavioral studies. In conclusion, the cell assembly-framework suggests a more fine-grained description of the issue of cortical laterality; it is not appropriate to ask whether "modules" supporting higher cortical functions are located either in the left or right hemisphere. Rather, it appears fruitful to ask how the neurons of transcortical cell assemblies are balanced between the hemispheres.

  20. Peripartum hysterectomy: an evolving picture.

    LENUS (Irish Health Repository)

    Turner, Michael J

    2012-02-01

    Peripartum hysterectomy (PH) is one of the obstetric catastrophes. Evidence is emerging that the role of PH in modern obstetrics is evolving. Improving management of postpartum hemorrhage and newer surgical techniques should decrease PH for uterine atony. Rising levels of repeat elective cesarean deliveries should decrease PH following uterine scar rupture in labor. Increasing cesarean rates, however, have led to an increase in the number of PHs for morbidly adherent placenta. In the case of uterine atony or rupture where PH is required, a subtotal PH is often sufficient. In the case of pathological placental localization involving the cervix, however, a total hysterectomy is required. Furthermore, the involvement of other pelvic structures may prospectively make the diagnosis difficult and the surgery challenging. If resources permit, PH for pathological placental localization merits a multidisciplinary approach. Despite advances in clinical practice, it is likely that peripartum hysterectomy will be more challenging for obstetricians in the future.

  1. Infrared spectroscopy of evolved objects

    International Nuclear Information System (INIS)

    Aitken, D.K.; Roche, P.F.

    1984-01-01

    In this review, the authors are concerned with spectroscopic observations of evolved objects made in the wavelength range 1-300μm. Spectroscopic observations can conveniently be divided into studies of narrow lines, bands and broader continua. The vibrational frequencies of molecular groups fall mainly in this spectral region and appear as vibration-rotation bands from the gas phase, and as less structured, but often broader, features from the solid state. Many ionic lines, including recombination lines of abundant species and fine structure lines of astrophysically important ions also appear in this region. The continuum can arise from a number of mechanisms - photospheric emission, radiation from dust, free-free transitions in ionized gas and non-thermal processes. (Auth.)

  2. Current concepts of chemotherapy and radiotherapy for small cell lung cancer

    International Nuclear Information System (INIS)

    Braun, T.J.; Bunn, P.A. Jr.

    1986-01-01

    Small cell lung cancer (SCLC) was projected to account for 20%-25% of the greater than 140,000 newly diagnosed lung cancers in 1985. If considered a separate disease entity, it would be the fourth leading cause of death by cancer. Previous studies have demonstrated distinct clinical and biologic features of small cell lung cancer, and early therapeutic trial results have demonstrated a high sensitivity to both chemotherapy and radiotherapy. More recent results demonstrated a marked survival improvement with the use of combination chemotherapy, which potentially cured a small minority of patients. Unfortunately, in most patients, drug resistance usually develops, as do chronic, often debilitating toxicities in the few long-term survivors. Although therapeutic advances have plateaued, new and important insights into the basic biology of the disease made the last several years offer the possibility of exciting new treatment approaches within the next decade. This chapter addresses our current understanding of therapy for small cell lung cancer, the current therapy questions under investigation, and potential future directions in clinical research

  3. Computational Genetic Regulatory Networks Evolvable, Self-organizing Systems

    CERN Document Server

    Knabe, Johannes F

    2013-01-01

    Genetic Regulatory Networks (GRNs) in biological organisms are primary engines for cells to enact their engagements with environments, via incessant, continually active coupling. In differentiated multicellular organisms, tremendous complexity has arisen in the course of evolution of life on earth. Engineering and science have so far achieved no working system that can compare with this complexity, depth and scope of organization. Abstracting the dynamics of genetic regulatory control to a computational framework in which artificial GRNs in artificial simulated cells differentiate while connected in a changing topology, it is possible to apply Darwinian evolution in silico to study the capacity of such developmental/differentiated GRNs to evolve. In this volume an evolutionary GRN paradigm is investigated for its evolvability and robustness in models of biological clocks, in simple differentiated multicellularity, and in evolving artificial developing 'organisms' which grow and express an ontogeny starting fr...

  4. Developing the Concept of Metalearning

    Science.gov (United States)

    Jackson, Norman

    2004-01-01

    The idea of metalearning was originally used by John Biggs (1985) to describe the state of 'being aware of and taking control of one's own learning'. This paper explores the concept through collaborative enquiry involving researchers and higher education teachers. An evolved conception is proposed in which metalearning is a subconcept within…

  5. Development and fabrication of a new concept planar-tubular solid oxide fuel cell (PT-SOFC)

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Y.; Chen, F. [CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, 230026 Anhui (China); Department of Mechanical Engineering, University of South Carolina, 300 Main Street, Columbia, SC 29208 (United States); Ding, D. [School of Materials Science and Engineering, Georgia Institute of Technology, Atlanta, GA 30332 (United States); Gao, J. [CAS Key Laboratory of Materials for Energy Conversion, Department of Materials Science and Engineering, University of Science and Technology of China, Hefei, 230026 Anhui (China)

    2011-06-15

    The paper reports a new concept of planar-tubular solid oxide fuel cell (PT-SOFC). Emphasis is on the fabrication of the required complex configuration of Ni-yttria-stabilised zirconia (YSZ) porous anode support by tert-butyl alcohol (TBA) based gelcasting, particularly the effects of solid loading, amounts of monomers and dispersant on the rheological behaviour of suspension, the shrinkage of a wet gelcast green body upon drying, and the properties of final sample after sintering at 1350 C and reduction from NiO-YSZ to Ni-YSZ. The results show that the gelcasting is a powerful method for preparation of the required complex configuration anode support. The anode support resulted from an optimised suspension with the solid loading of 25 vol% has uniform microstructure with 37% porosity, bending strength of 44 MPa and conductivity of 300 S cm{sup -} {sup 1} at 700 C, meeting the requirements for an anode support of SOFC. Based on the as-prepared anode support, PT-SOFC single cell of Ni-YSZ/YSZ/LSCF has been fabricated by slurry coating and co-sintering technique. The cell peak power density reaches 63, 106 and 141 mW cm {sup -} {sup 2} at 700, 750 and 800 C, respectively, using hydrogen as fuel and ambient air as oxidant. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  6. Protecting effects specifically from low doses of ionizing radiation to mammalian cells challenge the concept of linearity

    International Nuclear Information System (INIS)

    Feinendegen, L.E.; Sondhaus, C.A.; Altman, K.I.

    1998-01-01

    This report examines the origin of tissue effects that may follow from different cellular responses to low-dose irradiation, using published data. Two principal categories of cellular responses are considered. One response category relates to the probability of radiation-induced DNA damage. The other category consists of low-dose induced changes in intracellular signaling that induce mechanisms of DNA damage control different from those operating at high levels of exposure. Modeled in this way, tissue is treated as a complex adaptive system. The interaction of the various cellular responses results in a net tissue dose-effect relation that is likely to deviate from linearity in the low-dose region. This suggests that the LNT hypothesis should be reexamined. The aim of this paper is to demonstrate that by use of microdosimetric concepts, the energy deposited in cell mass can be related to the occurrence of cellular responses, both damaging and defensive

  7. Protecting effects specifically from low doses of ionizing radiation to mammalian cells challenge the concept of linearity

    Energy Technology Data Exchange (ETDEWEB)

    Feinendegen, L.E. [Brookhaven National Lab., Upton, NY (United States). Medical Dept.; Bond, V.P. [Washington State Univ., Richland, WA (United States); Sondhaus, C.A. [Univ. of Arizona, Tucson, AZ (United States). Dept. of Radiology and Radiation Control Office; Altman, K.I. [Univ. of Rochester Medical Center, NY (United States). Dept. of Biochemistry and Biophysics

    1998-12-31

    This report examines the origin of tissue effects that may follow from different cellular responses to low-dose irradiation, using published data. Two principal categories of cellular responses are considered. One response category relates to the probability of radiation-induced DNA damage. The other category consists of low-dose induced changes in intracellular signaling that induce mechanisms of DNA damage control different from those operating at high levels of exposure. Modeled in this way, tissue is treated as a complex adaptive system. The interaction of the various cellular responses results in a net tissue dose-effect relation that is likely to deviate from linearity in the low-dose region. This suggests that the LNT hypothesis should be reexamined. The aim of this paper is to demonstrate that by use of microdosimetric concepts, the energy deposited in cell mass can be related to the occurrence of cellular responses, both damaging and defensive.

  8. Clinical utility of circulating tumor cell counting through CellSearch®: the dilemma of a concept suspended in Limbo

    Directory of Open Access Journals (Sweden)

    Raimondi C

    2014-04-01

    Full Text Available Cristina Raimondi,1 Angela Gradilone,1 Giuseppe Naso,2 Enrico Cortesi,2 Paola Gazzaniga1 1Dipartimento Medicina Molecolare, Sapienza Università di Roma, Rome, Italy; 2Dipartimento di Scienze Radiologiche, Oncologiche e Anatomopatologiche, Sapienza Università di Roma, Rome, Italy Abstract: To date, 10 years after the first demonstration of circulating tumor cells (CTCs, prognostic significance in metastatic breast cancer using the US Food and Drug Administration–cleared system CellSearch®, the potential utility of CTCs in early clinical development of drugs, their role as a surrogate marker of response to therapy, and their molecular analysis for patient stratification for targeted therapies are still major unsolved questions. Great expectations are pinned on the ongoing interventional trials aimed to demonstrate that CTCs might be of value for guiding treatment of patients and predicting cancer progression. To fill the gap between theory and practice with regard to the clinical utility of CTCs, a bridge is needed, taking into account innovative design for clinical trials, a revised definition of traditional CTCs, next-generation CTC technology, the potential clinical application of CTC analysis in non-validated settings of disease, and finally, expanding the number of patients enrolled in the studies. In this regard, the results of the first European pooled analysis definitely validated the independent prognostic value of CTC counting in metastatic breast cancer patients. Keywords: CTC, clinical trials, prognosis

  9. Evaluation of total effort and risk of membraneless tubular fuel cell concept

    Energy Technology Data Exchange (ETDEWEB)

    Bambace, Luis Antonio Waack [Instituto Nacional de Pesquisas Espaciais - INPE, Sao Jose dos Campos, SP (Brazil)], e-mail: bambace@dem.inpe.br

    2010-07-01

    Traditionally people estimate project risks and duration by comparing predicted actions with similar ones. This methodology is rather difficult to apply in very innovative projects, as several of their Work Breakdown Structure (WBS) actions are quite new to a particular developer, even if this action is a standard procedure in another field or company. This paper proposes the use of an alternative methodology with fuel cell design example, which is inspired in Suh third axiom, Jelinsky-Moranda Model of software reliability (JMSRM). This model considers human error with JMRSR, relates the number of trials with entropy and search residual risk, feasibility with model uncertainty and acceptable and target risks, and the matching of search field and real solution field with statistical tools. (author)

  10. Diverticular Disease: Traditional and Evolving Paradigms.

    Science.gov (United States)

    Lamanna, Lenore; Moran, Patricia E

    Diverticular disease includes diverticulosis, which are sac protrusions of the intestinal mucosa, and diverticulitis, inflammation of the diverticula. Diverticular disease is listed as one of the top 10 leading physician diagnoses for gastrointestinal disorders in outpatient clinic visits in the United States. There are several classifications of diverticular disease ranging from asymptomatic diverticulosis to diverticulitis with complications. Several theories are linked to the development of diverticula which includes the physiology of the colon itself, collagen cross-linking, and recently challenged, low-fiber intake. The differential diagnoses of lower abdominal pain in addition to diverticular disease have overlapping signs and symptoms, which can make a diagnosis challenging. Identification of the distinct signs and symptoms of each classification will assist the practitioner in making the correct diagnosis and lead to appropriate management. The findings from recent studies have changed the paradigm of diverticular disease. The purpose of this article is to discuss traditional dogma and evolving concepts in the pathophysiology, prevention, and management of diverticular disease. Practitioners must be knowledgeable about diverticular disease for improved outcomes.

  11. The Evolving Classification of Pulmonary Hypertension.

    Science.gov (United States)

    Foshat, Michelle; Boroumand, Nahal

    2017-05-01

    - An explosion of information on pulmonary hypertension has occurred during the past few decades. The perception of this disease has shifted from purely clinical to incorporate new knowledge of the underlying pathology. This transfer has occurred in light of advancements in pathophysiology, histology, and molecular medical diagnostics. - To update readers about the evolving understanding of the etiology and pathogenesis of pulmonary hypertension and to demonstrate how pathology has shaped the current classification. - Information presented at the 5 World Symposia on pulmonary hypertension held since 1973, with the last meeting occurring in 2013, was used in this review. - Pulmonary hypertension represents a heterogeneous group of disorders that are differentiated based on differences in clinical, hemodynamic, and histopathologic features. Early concepts of pulmonary hypertension were largely influenced by pharmacotherapy, hemodynamic function, and clinical presentation of the disease. The initial nomenclature for pulmonary hypertension segregated the clinical classifications from pathologic subtypes. Major restructuring of this disease classification occurred between the first and second symposia, which was the first to unite clinical and pathologic information in the categorization scheme. Additional changes were introduced in subsequent meetings, particularly between the third and fourth World Symposia meetings, when additional pathophysiologic information was gained. Discoveries in molecular diagnostics significantly progressed the understanding of idiopathic pulmonary arterial hypertension. Continued advancements in imaging modalities, mechanistic pathogenicity, and molecular biomarkers will enable physicians to define pulmonary hypertension phenotypes based on the pathobiology and allow for treatment customization.

  12. CERN internal communication is evolving

    CERN Multimedia

    2016-01-01

    CERN news will now be regularly updated on the CERN People page (see here).      Dear readers, All over the world, communication is becoming increasingly instantaneous, with news published in real time on websites and social networks. In order to keep pace with these changes, CERN's internal communication is evolving too. From now on, you will be informed of what’s happening at CERN more often via the “CERN people” page, which will frequently be updated with news. The Bulletin is following this trend too: twice a month, we will compile the most important articles published on the CERN site, with a brand-new layout. You will receive an e-mail every two weeks as soon as this new form of the Bulletin is available. If you have interesting news or stories to share, tell us about them through the form at: https://communications.web.cern.ch/got-story-cern-website​. You can also find out about news from CERN in real time...

  13. Economies Evolve by Energy Dispersal

    Directory of Open Access Journals (Sweden)

    Stanley Salthe

    2009-10-01

    Full Text Available Economic activity can be regarded as an evolutionary process governed by the 2nd law of thermodynamics. The universal law, when formulated locally as an equation of motion, reveals that a growing economy develops functional machinery and organizes hierarchically in such a way as to tend to equalize energy density differences within the economy and in respect to the surroundings it is open to. Diverse economic activities result in flows of energy that will preferentially channel along the most steeply descending paths, leveling a non-Euclidean free energy landscape. This principle of 'maximal energy dispersal‘, equivalent to the maximal rate of entropy production, gives rise to economic laws and regularities. The law of diminishing returns follows from the diminishing free energy while the relation between supply and demand displays a quest for a balance among interdependent energy densities. Economic evolution is dissipative motion where the driving forces and energy flows are inseparable from each other. When there are multiple degrees of freedom, economic growth and decline are inherently impossible to forecast in detail. Namely, trajectories of an evolving economy are non-integrable, i.e. unpredictable in detail because a decision by a player will affect also future decisions of other players. We propose that decision making is ultimately about choosing from various actions those that would reduce most effectively subjectively perceived energy gradients.

  14. Recommendation in evolving online networks

    Science.gov (United States)

    Hu, Xiao; Zeng, An; Shang, Ming-Sheng

    2016-02-01

    Recommender system is an effective tool to find the most relevant information for online users. By analyzing the historical selection records of users, recommender system predicts the most likely future links in the user-item network and accordingly constructs a personalized recommendation list for each user. So far, the recommendation process is mostly investigated in static user-item networks. In this paper, we propose a model which allows us to examine the performance of the state-of-the-art recommendation algorithms in evolving networks. We find that the recommendation accuracy in general decreases with time if the evolution of the online network fully depends on the recommendation. Interestingly, some randomness in users' choice can significantly improve the long-term accuracy of the recommendation algorithm. When a hybrid recommendation algorithm is applied, we find that the optimal parameter gradually shifts towards the diversity-favoring recommendation algorithm, indicating that recommendation diversity is essential to keep a high long-term recommendation accuracy. Finally, we confirm our conclusions by studying the recommendation on networks with the real evolution data.

  15. Evolving Capabilities for Virtual Globes

    Science.gov (United States)

    Glennon, A.

    2006-12-01

    Though thin-client spatial visualization software like Google Earth and NASA World Wind enjoy widespread popularity, a common criticism is their general lack of analytical functionality. This concern, however, is rapidly being addressed; standard and advanced geographic information system (GIS) capabilities are being developed for virtual globes--though not centralized into a single implementation or software package. The innovation is mostly originating from the user community. Three such capabilities relevant to the earth science, education, and emergency management communities are modeling dynamic spatial phenomena, real-time data collection and visualization, and multi-input collaborative databases. Modeling dynamic spatial phenomena has been facilitated through joining virtual globe geometry definitions--like KML--to relational databases. Real-time data collection uses short scripts to transform user-contributed data into a format usable by virtual globe software. Similarly, collaborative data collection for virtual globes has become possible by dynamically referencing online, multi-person spreadsheets. Examples of these functions include mapping flows within a karst watershed, real-time disaster assessment and visualization, and a collaborative geyser eruption spatial decision support system. Virtual globe applications will continue to evolve further analytical capabilities, more temporal data handling, and from nano to intergalactic scales. This progression opens education and research avenues in all scientific disciplines.

  16. Adaptive inferential sensors based on evolving fuzzy models.

    Science.gov (United States)

    Angelov, Plamen; Kordon, Arthur

    2010-04-01

    A new technique to the design and use of inferential sensors in the process industry is proposed in this paper, which is based on the recently introduced concept of evolving fuzzy models (EFMs). They address the challenge that the modern process industry faces today, namely, to develop such adaptive and self-calibrating online inferential sensors that reduce the maintenance costs while keeping the high precision and interpretability/transparency. The proposed new methodology makes possible inferential sensors to recalibrate automatically, which reduces significantly the life-cycle efforts for their maintenance. This is achieved by the adaptive and flexible open-structure EFM used. The novelty of this paper lies in the following: (1) the overall concept of inferential sensors with evolving and self-developing structure from the data streams; (2) the new methodology for online automatic selection of input variables that are most relevant for the prediction; (3) the technique to detect automatically a shift in the data pattern using the age of the clusters (and fuzzy rules); (4) the online standardization technique used by the learning procedure of the evolving model; and (5) the application of this innovative approach to several real-life industrial processes from the chemical industry (evolving inferential sensors, namely, eSensors, were used for predicting the chemical properties of different products in The Dow Chemical Company, Freeport, TX). It should be noted, however, that the methodology and conclusions of this paper are valid for the broader area of chemical and process industries in general. The results demonstrate that well-interpretable and with-simple-structure inferential sensors can automatically be designed from the data stream in real time, which predict various process variables of interest. The proposed approach can be used as a basis for the development of a new generation of adaptive and evolving inferential sensors that can address the

  17. Peripheral blood cell microRNA quantification during the first trimester predicts preeclampsia: Proof of concept.

    Directory of Open Access Journals (Sweden)

    Edward E Winger

    Full Text Available We investigated the capacity of microRNAs isolated from peripheral blood buffy coat collected late during the first trimester to predict preeclampsia.The cohort study comprised 48 pregnant women with the following pregnancy outcomes: 8 preeclampsia and 40 with normal delivery outcomes. Quantitative rtPCR was performed on a panel of 30 microRNAs from buffy coat samples drawn at a mean of 12.7±0.5 weeks gestation. MicroRNA Risk Scores were calculated and AUC-ROC calculations derived.The AUC-ROC for preeclampsia risk was 0.91 (p<0.0001. When women with normal delivery and high-risk background (those with SLE/APS, chronic hypertension and/or Type 2 Diabetes were compared to women who developed preeclampsia but with a normal risk background (without these mentioned risk factors, preeclampsia was still predicted with an AUC-ROC of 0.92 (p<0.0001.MicroRNA quantification of peripheral immune cell microRNA provides sensitive and specific prediction of preeclampsia in the first trimester of pregnant women. With this study, we extend the range during which disorders of the placental bed may be predicted from early to the end of the first trimester. This study confirms that buffy coat may be used as a sample preparation.

  18. New Concepts for Translational Head and Neck Oncology: Lessons from HPV-Related Oropharyngeal Squamous Cell Carcinomas

    International Nuclear Information System (INIS)

    Kostareli, Efterpi; Holzinger, Dana; Hess, Jochen

    2012-01-01

    Human papillomavirus (HPV) infection is well established as an etiological agent responsible for a number of pathologies affecting the stratified epithelia of skin and anogenital sites. More recently, the infection by (mucosal) high-risk HPV types has also been found to be causally associated with squamous cell carcinoma in the head and neck region (HNSCC), especially in the oropharynx. Intriguingly, HPV-related oropharyngeal squamous cell carcinomas (OPSCC) represent a distinct clinical entity compared to HPV-negative tumors with particular regard to treatment–response and survival outcome. The association between HPV infection and OPSCC may therefore have important implications for the prevention and/or treatment of OPSCC. The improved survival of patients with HPV-related tumors also raises the question, as to whether a better understanding of the underlying differences may help to identify new therapeutic concepts that could be used in targeted therapy for HPV-negative and improved therapy for HPV-positive cancers. This review summarizes the most recent advances in our understanding of the molecular principles of HPV-related OPSCC, mainly based on functional genomic approaches, but also emphasizes the significant role played by the tumor microenvironment, especially the immune system, for improved clinical outcome and differential sensitivity of HPV-related tumors to current treatment options.

  19. Cell-Phone Addiction: A Review

    OpenAIRE

    De-Sola Guti?rrez, Jos?; Rodr?guez de Fonseca, Fernando; Rubio, Gabriel

    2016-01-01

    We present a review of the studies that have been published about addiction to cell phones. We analyze the concept of cell-phone addiction as well as its prevalence, study methodologies, psychological features, and associated psychiatric comorbidities. Research in this field has generally evolved from a global view of the cell phone as a device to its analysis via applications and contents. The diversity of criteria and methodological approaches that have been used is notable, as is a certain...

  20. Actin Immobilization on Chitin for Purifying Myosin II: A Laboratory Exercise That Integrates Concepts of Molecular Cell Biology and Protein Chemistry

    Science.gov (United States)

    de Souza, Marcelle Gomes; Grossi, Andre Luiz; Pereira, Elisangela Lima Bastos; da Cruz, Carolina Oliveira; Mendes, Fernanda Machado; Cameron, Luiz Claudio; Paiva, Carmen Lucia Antao

    2008-01-01

    This article presents our experience on teaching biochemical sciences through an innovative approach that integrates concepts of molecular cell biology and protein chemistry. This original laboratory exercise is based on the preparation of an affinity chromatography column containing F-actin molecules immobilized on chitin particles for purifying…

  1. Quantum mechanics in an evolving Hilbert space

    Science.gov (United States)

    Artacho, Emilio; O'Regan, David D.

    2017-03-01

    Many basis sets for electronic structure calculations evolve with varying external parameters, such as moving atoms in dynamic simulations, giving rise to extra derivative terms in the dynamical equations. Here we revisit these derivatives in the context of differential geometry, thereby obtaining a more transparent formalization, and a geometrical perspective for better understanding the resulting equations. The effect of the evolution of the basis set within the spanned Hilbert space separates explicitly from the effect of the turning of the space itself when moving in parameter space, as the tangent space turns when moving in a curved space. New insights are obtained using familiar concepts in that context such as the Riemann curvature. The differential geometry is not strictly that for curved spaces as in general relativity, a more adequate mathematical framework being provided by fiber bundles. The language used here, however, will be restricted to tensors and basic quantum mechanics. The local gauge implied by a smoothly varying basis set readily connects with Berry's formalism for geometric phases. Generalized expressions for the Berry connection and curvature are obtained for a parameter-dependent occupied Hilbert space spanned by nonorthogonal Wannier functions. The formalism is applicable to basis sets made of atomic-like orbitals and also more adaptative moving basis functions (such as in methods using Wannier functions as intermediate or support bases), but should also apply to other situations in which nonorthogonal functions or related projectors should arise. The formalism is applied to the time-dependent quantum evolution of electrons for moving atoms. The geometric insights provided here allow us to propose new finite-difference time integrators, and also better understand those already proposed.

  2. Real-time evolvable pulse shaper for radiation measurements

    Energy Technology Data Exchange (ETDEWEB)

    Lanchares, Juan, E-mail: julandan@dacya.ucm.es [Facultad de Informática, Universidad Complutense de Madrid (UCM), C/Prof. José García Santesmases s/n, 28040 Madrid (Spain); Garnica, Oscar, E-mail: ogarnica@dacya.ucm.es [Facultad de Informática, Universidad Complutense de Madrid (UCM), C/Prof. José García Santesmases s/n, 28040 Madrid (Spain); Risco-Martín, José L., E-mail: jlrisco@dacya.ucm.es [Facultad de Informática, Universidad Complutense de Madrid (UCM), C/Prof. José García Santesmases s/n, 28040 Madrid (Spain); Ignacio Hidalgo, J., E-mail: hidalgo@dacya.ucm.es [Facultad de Informática, Universidad Complutense de Madrid (UCM), C/Prof. José García Santesmases s/n, 28040 Madrid (Spain); Regadío, Alberto, E-mail: alberto.regadio@insa.es [Área de Tecnologías Electrónicas, Instituto Nacional de Técnica Aeroespacial (INTA), 28850 Torrejón de Ardoz, Madrid (Spain)

    2013-11-01

    In the last two decades, recursive algorithms for real-time digital pulse shaping in pulse height measurements have been developed and published in number of articles and textbooks. All these algorithms try to synthesize in real time optimum or near optimum shapes in the presence of noise. Even though some of these shapers can be considered effective designs, some side effects like aging cannot be ignored. We may observe that after sensors degradation, the signal obtained is not valid. In this regard, we present in this paper a novel technique that, based on evolvable hardware concepts, is able to evolve the degenerated shaper into a new design with better performance than the original one under the new sensor features.

  3. Evolving Technologies: A View to Tomorrow

    Science.gov (United States)

    Tamarkin, Molly; Rodrigo, Shelley

    2011-01-01

    Technology leaders must participate in strategy creation as well as operational delivery within higher education institutions. The future of higher education--the view to tomorrow--is irrevocably integrated and intertwined with evolving technologies. This article focuses on two specific evolving technologies: (1) alternative IT sourcing; and (2)…

  4. Evolvability Search: Directly Selecting for Evolvability in order to Study and Produce It

    DEFF Research Database (Denmark)

    Mengistu, Henok; Lehman, Joel Anthony; Clune, Jeff

    2016-01-01

    of evolvable digital phenotypes. Although some types of selection in evolutionary computation indirectly encourage evolvability, one unexplored possibility is to directly select for evolvability. To do so, we estimate an individual's future potential for diversity by calculating the behavioral diversity of its...... immediate offspring, and select organisms with increased offspring variation. While the technique is computationally expensive, we hypothesized that direct selection would better encourage evolvability than indirect methods. Experiments in two evolutionary robotics domains confirm this hypothesis: in both...... domains, such Evolvability Search produces solutions with higher evolvability than those produced with Novelty Search or traditional objective-based search algorithms. Further experiments demonstrate that the higher evolvability produced by Evolvability Search in a training environment also generalizes...

  5. Clinical reasoning: concept analysis.

    Science.gov (United States)

    Simmons, Barbara

    2010-05-01

    This paper is a report of a concept analysis of clinical reasoning in nursing. Clinical reasoning is an ambiguous term that is often used synonymously with decision-making and clinical judgment. Clinical reasoning has not been clearly defined in the literature. Healthcare settings are increasingly filled with uncertainty, risk and complexity due to increased patient acuity, multiple comorbidities, and enhanced use of technology, all of which require clinical reasoning. Data sources. Literature for this concept analysis was retrieved from several databases, including CINAHL, PubMed, PsycINFO, ERIC and OvidMEDLINE, for the years 1980 to 2008. Rodgers's evolutionary method of concept analysis was used because of its applicability to concepts that are still evolving. Multiple terms have been used synonymously to describe the thinking skills that nurses use. Research in the past 20 years has elucidated differences among these terms and identified the cognitive processes that precede judgment and decision-making. Our concept analysis defines one of these terms, 'clinical reasoning,' as a complex process that uses cognition, metacognition, and discipline-specific knowledge to gather and analyse patient information, evaluate its significance, and weigh alternative actions. This concept analysis provides a middle-range descriptive theory of clinical reasoning in nursing that helps clarify meaning and gives direction for future research. Appropriate instruments to operationalize the concept need to be developed. Research is needed to identify additional variables that have an impact on clinical reasoning and what are the consequences of clinical reasoning in specific situations.

  6. Sex determination: ways to evolve a hermaphrodite.

    OpenAIRE

    Braendle , Christian; Félix , Marie-Anne

    2006-01-01

    Most species of the nematode genus Caenorhabditis reproduce through males and females; C. elegans and C. briggsae, however, produce self-fertile hermaphrodites instead of females. These transitions to hermaphroditism evolved convergently through distinct modifications of germline sex determination mechanisms.

  7. WSC-07: Evolving the Web Services Challenge

    NARCIS (Netherlands)

    Blake, M. Brian; Cheung, William K.W.; Jaeger, Michael C.; Wombacher, Andreas

    Service-oriented architecture (SOA) is an evolving architectural paradigm where businesses can expose their capabilities as modular, network-accessible software services. By decomposing capabilities into modular services, organizations can share their offerings at multiple levels of granularity

  8. Marshal: Maintaining Evolving Models, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — SIFT proposes to design and develop the Marshal system, a mixed-initiative tool for maintaining task models over the course of evolving missions. Marshal-enabled...

  9. Satcom access in the Evolved Packet Core

    NARCIS (Netherlands)

    Cano Soveri, M.D.; Norp, A.H.J.; Popova, M.P.

    2011-01-01

    Satellite communications (Satcom) networks are increasingly integrating with terrestrial communications networks, namely Next Generation Networks (NGN). In the area of NGN the Evolved Packet Core (EPC) is a new network architecture that can support multiple access technologies. When Satcom is

  10. Satcom access in the evolved packet core

    NARCIS (Netherlands)

    Cano, M.D.; Norp, A.H.J.; Popova, M.P.

    2012-01-01

    Satellite communications (Satcom) networks are increasingly integrating with terrestrial communications networks, namely Next Generation Networks (NGN). In the area of NGN the Evolved Packet Core (EPC) is a new network architecture that can support multiple access technologies. When Satcom is

  11. Social networks: Evolving graphs with memory dependent edges

    Science.gov (United States)

    Grindrod, Peter; Parsons, Mark

    2011-10-01

    The plethora of digital communication technologies, and their mass take up, has resulted in a wealth of interest in social network data collection and analysis in recent years. Within many such networks the interactions are transient: thus those networks evolve over time. In this paper we introduce a class of models for such networks using evolving graphs with memory dependent edges, which may appear and disappear according to their recent history. We consider time discrete and time continuous variants of the model. We consider the long term asymptotic behaviour as a function of parameters controlling the memory dependence. In particular we show that such networks may continue evolving forever, or else may quench and become static (containing immortal and/or extinct edges). This depends on the existence or otherwise of certain infinite products and series involving age dependent model parameters. We show how to differentiate between the alternatives based on a finite set of observations. To test these ideas we show how model parameters may be calibrated based on limited samples of time dependent data, and we apply these concepts to three real networks: summary data on mobile phone use from a developing region; online social-business network data from China; and disaggregated mobile phone communications data from a reality mining experiment in the US. In each case we show that there is evidence for memory dependent dynamics, such as that embodied within the class of models proposed here.

  12. Evolving effective incremental SAT solvers with GP

    OpenAIRE

    Bader, Mohamed; Poli, R.

    2008-01-01

    Hyper-Heuristics could simply be defined as heuristics to choose other heuristics, and it is a way of combining existing heuristics to generate new ones. In a Hyper-Heuristic framework, the framework is used for evolving effective incremental (Inc*) solvers for SAT. We test the evolved heuristics (IncHH) against other known local search heuristics on a variety of benchmark SAT problems.

  13. Systems biology approach to transplant tolerance: proof of concept experiments using RNA interference (RNAi) to knock down hub genes in Jurkat and HeLa cells in vitro.

    Science.gov (United States)

    Lwin, Wint Wah; Park, Ken; Wauson, Matthew; Gao, Qin; Finn, Patricia W; Perkins, David; Khanna, Ajai

    2012-07-01

    Systems biology is gaining importance in studying complex systems such as the functional interconnections of human genes [1]. To investigate the molecular interactions involved in T cell immune responses, we used databases of physical gene-gene interactions to constructed molecular interaction networks (interconnections) with R language algorithms. This helped to identify highly interconnected "hub" genes AT(1)P5C1, IL6ST, PRKCZ, MYC, FOS, JUN, and MAPK1. We hypothesized that suppression of these hub genes in the gene network would result in significant phenotypic effects on T cells and examined this in vitro. The molecular interaction networks were then analyzed and visualized with Cytoscape. Jurkat and HeLa cells were transfected with siRNA for the selected hub genes. Cell proliferation was measured using ATP luminescence and BrdU labeling, which were measured 36, 72, and 96 h after activation. Following T cell stimulation, we found a significant decrease in ATP production (P cells. However, HeLa cells showed a significant (P cell proliferation when the genes MAPK1, IL6ST, ATP5C1, JUN, and FOS were knocked down. In both Jurkat and HeLa cells, targeted gene knockdown using siRNA showed decreased cell proliferation and ATP production in both Jurkat and HeLa cells. However, Jurkat T cells and HELA cells use different hub genes to regulate activation responses. This experiment provides proof of principle of applying siRNA knockdown of T cell hub genes to evaluate their proliferative capacity and ATP production. This novel concept outlines a systems biology approach to identify hub genes for targeted therapeutics. Published by Elsevier Inc.

  14. Concepts in catalysis

    International Nuclear Information System (INIS)

    Boudart, M.

    1992-01-01

    This paper reports on concept in catalysis which are very important in heterogeneous catalysis, even today, when in spite of surface science, the complexity of events at a real catalytic surface is still evading the understanding necessary for design. In this paper the authors will attempt to give an update on evolving concepts in heterogeneous catalysis. The topics include: counting active centers on metal surfaces; the notion of turnover frequency for a catalytic cycle; the concept of structure (in) sensitive reactions; the ensemble (geometric) vs. The ligand (electronic) effect following Sachtler's school; the idea of a rate determining step and of a most abundant reactive intermediate; the effect of surface non-uniformity on catalytic kinetics; what makes catalytic cycles turnover

  15. Space Mission Concept Development Using Concept Maturity Levels

    Science.gov (United States)

    Wessen, Randii R.; Borden, Chester; Ziemer, John; Kwok, Johnny

    2013-01-01

    Over the past five years, pre-project formulation experts at the Jet Propulsion Laboratory (JPL) has developed and implemented a method for measuring and communicating the maturity of space mission concepts. Mission concept development teams use this method, and associated tools, prior to concepts entering their Formulation Phases (Phase A/B). The organizing structure is Concept Maturity Level (CML), which is a classification system for characterizing the various levels of a concept's maturity. The key strength of CMLs is the ability to evolve mission concepts guided by an incremental set of assessment needs. The CML definitions have been expanded into a matrix form to identify the breadth and depth of analysis needed for a concept to reach a specific level of maturity. This matrix enables improved assessment and communication by addressing the fundamental dimensions (e.g., science objectives, mission design, technical risk, project organization, cost, export compliance, etc.) associated with mission concept evolution. JPL's collaborative engineering, dedicated concept development, and proposal teams all use these and other CML-appropriate design tools to advance their mission concept designs. This paper focuses on mission concept's early Pre-Phase A represented by CMLs 1- 4. The scope was limited due to the fact that CMLs 5 and 6 are already well defined based on the requirements documented in specific Announcement of Opportunities (AO) and Concept Study Report (CSR) guidelines, respectively, for competitive missions; and by NASA's Procedural Requirements NPR 7120.5E document for Projects in their Formulation Phase.

  16. Cell Identification based on Received Signal Strength Fingerprints: Concept and Application towards Energy Saving in Cellular Networks

    Directory of Open Access Journals (Sweden)

    Elke Roth-Mandutz

    2014-09-01

    Full Text Available The increasing deployment of small cells aimed at off-loading data traffic from macrocells in heterogeneous networks has resulted in a drastic increase in energy consumption in cellular networks. Energy consumption can be optimized in a selforganized way by adapting the number of active cells in response to the current traffic demand. In this paper we concentrate on the complex problem of how to identify small cells to be reactivated in situations where multiple cells are concurrently inactive. Solely based on the received signal strength, we present cell-specific patterns for the generation of unique cell fingerprints. The cell fingerprints of the deactivated cells are matched with measurements from a high data rate demanding mobile device to identify the most appropriate candidate. Our scheme results in a matching success rate of up to 100% to identify the best cell depending on the number of cells to be activated.

  17. High somatic cell counts and changes in milk fat and protein contents around insemination are negatively associated with conception in dairy cows.

    Science.gov (United States)

    Albaaj, Ahmad; Foucras, Gilles; Raboisson, Didier

    2017-01-15

    The fertility of dairy cows has decreased dramatically worldwide over the last few decades, and several causes of this trend have been reported. Several studies have associated compromised udder health with deteriorating reproduction performance. Subclinical ketosis (SCK) has also been reported to be a risk factor for decreased conception. The objective of the present study was to describe how SCK might interact with the reported association between udder health and conception in dairy cows. Data from the French Milk Control Program and data on 8,549,667 instances of artificial insemination (AI) and their corresponding preceding and subsequent test-days from 5,979,701 Holstein cows were examined over a 5-year period (2008-2012). The effect of udder health was evaluated through a low (L) or high (H) somatic cell count (SCC) before and after AI using a threshold of 200,000 cells/mL, and transformed into four groups (LL, LH, HL, and HH). Three proxies for defining SCK were proposed based on the milk fat and protein content (or their ratio) before AI. Statistical analysis first included a generalized additive model to help define the optimal threshold values. Next, a logistic regression with a Poisson correction was performed. On average, the risk of conception at first AI was reduced by 14% for LH or HH cows (relative risk [and 95% CI] = 0.86 [0.85-0.87]) when the SCC increased or remained high within 40 days before and after AI, relative to LL group. The reduction of conception success associated with SCK (fat and protein contents changes) varied from 3% to 17% depending on the used SCK proxy. Including the interaction term SCC ∗ SCK clearly showed that the association of increased SCC around AI with conception success was modified by the presence of SCK. A cow that already has SCK and experiences an increase in SCC around or after AI exhibits up to 2 times further decrease in conception success compared with a cow with a high SCC and no SCK. In conclusion

  18. Concepts of formal concept analysis

    Science.gov (United States)

    Žáček, Martin; Homola, Dan; Miarka, Rostislav

    2017-07-01

    The aim of this article is apply of Formal Concept Analysis on concept of world. Formal concept analysis (FCA) as a methodology of data analysis, information management and knowledge representation has potential to be applied to a verity of linguistic problems. FCA is mathematical theory for concepts and concept hierarchies that reflects an understanding of concept. Formal concept analysis explicitly formalizes extension and intension of a concept, their mutual relationships. A distinguishing feature of FCA is an inherent integration of three components of conceptual processing of data and knowledge, namely, the discovery and reasoning with concepts in data, discovery and reasoning with dependencies in data, and visualization of data, concepts, and dependencies with folding/unfolding capabilities.

  19. Analysis of motility in multicellular Chlamydomonas reinhardtii evolved under predation.

    Directory of Open Access Journals (Sweden)

    Margrethe Boyd

    Full Text Available The advent of multicellularity was a watershed event in the history of life, yet the transition from unicellularity to multicellularity is not well understood. Multicellularity opens up opportunities for innovations in intercellular communication, cooperation, and specialization, which can provide selective advantages under certain ecological conditions. The unicellular alga Chlamydomonas reinhardtii has never had a multicellular ancestor yet it is closely related to the volvocine algae, a clade containing taxa that range from simple unicells to large, specialized multicellular colonies. Simple multicellular structures have been observed to evolve in C. reinhardtii in response to predation or to settling rate-based selection. Structures formed in response to predation consist of individual cells confined within a shared transparent extracellular matrix. Evolved isolates form such structures obligately under culture conditions in which their wild type ancestors do not, indicating that newly-evolved multicellularity is heritable. C. reinhardtii is capable of photosynthesis, and possesses an eyespot and two flagella with which it moves towards or away from light in order to optimize input of radiant energy. Motility contributes to C. reinhardtii fitness because it allows cells or colonies to achieve this optimum. Utilizing phototaxis to assay motility, we determined that newly evolved multicellular strains do not exhibit significant directional movement, even though the flagellae of their constituent unicells are present and active. In C. reinhardtii the first steps towards multicellularity in response to predation appear to result in a trade-off between motility and differential survivorship, a trade-off that must be overcome by further genetic change to ensure long-term success of the new multicellular organism.

  20. Optics of the CuGaSe{sub 2} solar cell for highly efficient tandem concepts; Optik der CuGaSe{sub 2}-Solarzelle fuer hocheffiziente Tandemkonzepte

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, Martina

    2010-01-25

    A principle aim of solar cell research lies in optimizing the exploitation of the incident solar light. Yet, for single junction solar cells there exists an efficiency limit as described by Shockley and Queisser. The only concept realized so far to overcome this threshold is - apart from concentration - the multijunction solar cell. However, any kind of multijunction design poses new challenges: The upper wide-gap solar cell (top cell) needs to show efficient light absorption in the short-wavelength region. At the same time sufficient transmission for long-wavelength light is required which then needs to be absorbed effectively by the low-gap bottom cell. In tandem solar cells a proper light management in top and bottom solar cell is of great importance. This work focuses on chalcopyrite-based tandem solar cells. For the wide-bandgap IR-transparent ZnO:Al/i-ZnO/CdS/CuGaSe{sub 2}/SnO{sub 2}:F/glass solar cell an optical model has been established. Starting from modeling each of the individual layers building the stack the optical behavior of the complete thin film system of the top cell could be described. Carefully selected layer combinations and comparison of experimental and calculated data allowed for the attribution of transmission losses to the distinct material properties. Defects in the absorber are of crucial importance but also free carrier absorption in the window and in the transparent back contact contribute significantly to optical losses. The quantification of the losses was achieved by calculating the effects of reduced top cell transmission on the photo current of a simplified bottom cell. An extension of the optical model allowed to calculate the effective absorption in the individual layers and to determine reflection losses at the interfaces. From these results an optimized top cell stack was derived which is characterized by A) simulation of the monolithic integration, B) reduced layer thicknesses wherever possible from the electrical point of

  1. Adipose stem cells for intervertebral disc regeneration: Current status and concepts for the future: Tissue Engineering Review Series

    NARCIS (Netherlands)

    Hoogendoorn, R.J.W.; Lu, Z.F.; Kroeze, R.J.; Bank, R.A.; Wuisman, P.I.; Helder, M.N.

    2008-01-01

    Introduction Degenerative disc disease and emerging biological treatment approaches Stem cell sources Integration of ASC-based regenerative medicine and surgery In vitro studies Animal models Cells in disc regeneration in vivo In vivo studies Perspective Conclusions Abstract New regenerative

  2. Interactively Evolving Compositional Sound Synthesis Networks

    DEFF Research Database (Denmark)

    Jónsson, Björn Þór; Hoover, Amy K.; Risi, Sebastian

    2015-01-01

    the space of potential sounds that can be generated through such compositional sound synthesis networks (CSSNs). To study the effect of evolution on subjective appreciation, participants in a listener study ranked evolved timbres by personal preference, resulting in preferences skewed toward the first......While the success of electronic music often relies on the uniqueness and quality of selected timbres, many musicians struggle with complicated and expensive equipment and techniques to create their desired sounds. Instead, this paper presents a technique for producing novel timbres that are evolved...

  3. Quality of life philosophy VI. The concepts.

    Science.gov (United States)

    Ventegodt, Søren; Andersen, Niels Jørgen; Merrick, Joav

    2003-12-01

    The about a hundred central concepts related to research in the global quality of life can, in a holistic medical frame of interpretation, be organized under ten abstract key concepts: existence, creation of the world, state of being, daily living, talents, relations, sex, health, personal development, and therapy with subthemes as discussed in this paper. The paper shows that the concepts in each group can be seen as related to each other in a quite intuitive and logical way, to give a coherent quality of life philosophy that allows the physician to encourage, inspire, and support his patient. In every consultation, one new concept and idea of existence can be taught to the patient, helping him or her to realize the meaning of life, the source of joy, and the reason for the actual suffering. In this way, we help the patient to mobilize hidden and known resources and to improve quality of life, subjective health, and the ability to function. The concepts were harvested in 2003 at a Nordic seminar on quality of life research, held in Sweden. Life does not only cohere on the inside, but also on the outside. The same power that ties together all the cells in our body, seems to tie us together in relationships and new wholeness. This power evolves into new kinds of relations that unite on more and more complex levels, with the global ecosystem as the highest known level. Our intentions come from this coherent matrix of life. In the beginning of our life, the web of life itself gave birth to our fundamental purpose of life. The abstract purpose determines the frame of interpretation of reality: How we will perceive ourselves throughout life, our inner life, and the world around us. The frame of interpretation is pitched in language and concepts, in fact it creates our perceptions. Based on these perceptions and our purposes of life, our behavior arises. Our consciousness evolves through the witnessing of our behavior and through the response caused by it. Through the

  4. Quality of Life Philosophy VI. The Concepts

    Directory of Open Access Journals (Sweden)

    Soren Ventegodt

    2003-01-01

    Full Text Available The about a hundred central concepts related to research in the global quality of life can, in a holistic medical frame of interpretation, be organized under ten abstract key concepts: existence, creation of the world, state of being, daily living, talents, relations, sex, health, personal development, and therapy with subthemes as discussed in this paper. The paper shows that the concepts in each group can be seen as related to each other in a quite intuitive and logical way, to give a coherent quality of life philosophy that allows the physician to encourage, inspire, and support his patient. In every consultation, one new concept and idea of existence can be taught to the patient, helping him or her to realize the meaning of life, the source of joy, and the reason for the actual suffering. In this way, we help the patient to mobilize hidden and known resources and to improve quality of life, subjective health, and the ability to function. The concepts were harvested in 2003 at a Nordic seminar on quality of life research, held in Sweden. Life does not only cohere on the inside, but also on the outside. The same power that ties together all the cells in our body, seems to tie us together in relationships and new wholeness. This power evolves into new kinds of relations that unite on more and more complex levels, with the global ecosystem as the highest known level.Our intentions come from this coherent matrix of life. In the beginning of our life, the web of life itself gave birth to our fundamental purpose of life. The abstract purpose determines the frame of interpretation of reality: How we will perceive ourselves throughout life, our inner life, and the world around us. The frame of interpretation is pitched in language and concepts, in fact it creates our perceptions. Based on these perceptions and our purposes of life, our behavior arises. Our consciousness evolves through the witnessing of our behavior and through the response caused by

  5. Indian concepts on sexuality.

    Science.gov (United States)

    Chakraborty, Kaustav; Thakurata, Rajarshi Guha

    2013-01-01

    India is a vast country depicting wide social, cultural and sexual variations. Indian concept of sexuality has evolved over time and has been immensely influenced by various rulers and religions. Indian sexuality is manifested in our attire, behavior, recreation, literature, sculptures, scriptures, religion and sports. It has influenced the way we perceive our health, disease and device remedies for the same. In modern era, with rapid globalization the unique Indian sexuality is getting diffused. The time has come to rediscover ourselves in terms of sexuality to attain individual freedom and to reinvest our energy to social issues related to sexuality.

  6. . Modern concepts on carcinogenesis: the value of insufficiency of malignant cell elimination mechanisms in the tumor progression in case of neoplasia at different localizations

    Directory of Open Access Journals (Sweden)

    Chesnokova N.P.

    2016-03-01

    Full Text Available The article presents the review of contemporary concepts of tumor induction mechanisms applicable for neoplastic transformation, promotion and proliferation. The paper also contains an in-depth analysis of results of authors' own observations and study of immunological protection mechanisms of a significant number of patients diagnosed with oncopathologies of mammary and thyroid glands as well as adenocarcinoma of ascending colon. We have established common development patterns of T-cell and B-cell immunodeficiencies that are not influenced by location and proliferation of neoplastic tumors; the progress of such immunodeficincies, however, depends on regional metastasis development. Thus, we can conclude that insufficiency of immunological defense mechanisms leading to disruption of maligned cell elimination process is the primary pathogenic factor for metastatic tumor development.

  7. On the Benefits of Divergent Search for Evolved Representations

    DEFF Research Database (Denmark)

    Lehman, Joel; Risi, Sebastian; Stanley, Kenneth O

    2012-01-01

    Evolved representations in evolutionary computation are often fragile, which can impede representation-dependent mechanisms such as self-adaptation. In contrast, evolved representations in nature are robust, evolvable, and creatively exploit available representational features. This paper provide...

  8. Faith: a concept analysis.

    Science.gov (United States)

    Dyess, Susan Macleod

    2011-12-01

    This paper reports a concept analysis of faith. There are numerous scholars who consider spirituality and religiosity as they relate to health and nursing. Faith is often implied as linked to these concepts but deserves distinct exploration. In addition, as nursing practice conducted within communities of faith continues to emerge, concept clarification of faith is warranted. Qualitative analysis deliberately considered the concept of faith within the lens of Margaret Newman's health as expanding consciousness. Data sources used included a secondary analysis of stories collected within a study conducted in 2008, two specific reconstructed stories, the identification of attributes noted within these various stories and selected philosophical literature from 1950 to 2009.  A definition was identified from the analysis; faith is an evolving pattern of believing, that grounds and guides authentic living and gives meaning in the present moment of inter-relating. Four key attributes of faith were also identified as focusing on beliefs, foundational meaning for life, living authentically in accordance with beliefs, and interrelating with self, others and/or Divine. Although a seemingly universal concept, faith was defined individually. Faith appeared to be broader than spiritual practices and religious ritual and became the very foundation that enabled human beings to make sense of their world and circumstances. More work is needed to understand how faith community nursing can expand the traditional understanding of denominationally defined faith community practices and how nurses can support faith for individuals with whom they encounter within all nursing practice. © 2011 Blackwell Publishing Ltd.

  9. Preface: evolving rotifers, evolving science: Proceedings of the XIV International Rotifer Symposium

    Czech Academy of Sciences Publication Activity Database

    Devetter, Miloslav; Fontaneto, D.; Jersabek, Ch.D.; Welch, D.B.M.; May, L.; Walsh, E.J.

    2017-01-01

    Roč. 796, č. 1 (2017), s. 1-6 ISSN 0018-8158 Institutional support: RVO:60077344 Keywords : evolving rotifers * 14th International Rotifer Symposium * evolving science Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 2.056, year: 2016

  10. Mathematical Creativity, Cohen Forcing, and Evolving Systems: Elements for a Case Study on Paul Cohen

    Science.gov (United States)

    Dickman, Benjamin

    2013-01-01

    The Evolving Systems approach to case studies due initially to Piaget-contemporary Howard Gruber, and complemented by subsequent work on sociocultural factors developed by Mihaly Csikszentmihalyi and others, provides an inroad for examining creative achievements in a variety of domains. This paper provides a proof of concept for how one might…

  11. Views on Evolvability of Embedded Systems

    NARCIS (Netherlands)

    Laar, P. van de; Punter, T.

    2011-01-01

    Evolvability, the ability to respond effectively to change, represents a major challenge to today's high-end embedded systems, such as those developed in the medical domain by Philips Healthcare. These systems are typically developed by multi-disciplinary teams, located around the world, and are in

  12. Views on evolvability of embedded systems

    NARCIS (Netherlands)

    Laar, van de P.J.L.J.; Punter, H.T.

    2011-01-01

    Evolvability, the ability to respond effectively to change, represents a major challenge to today's high-end embedded systems, such as those developed in the medical domain by Philips Healthcare. These systems are typically developed by multi-disciplinary teams, located around the world, and are in

  13. Designing Garments to Evolve Over Time

    DEFF Research Database (Denmark)

    Riisberg, Vibeke; Grose, Lynda

    2017-01-01

    This paper proposes a REDO of the current fashion paradigm by investigating how garments might be designed to evolve over time. The purpose is to discuss ways of expanding the traditional role of the designer to include temporal dimensions of creating, producing and using clothes and to suggest...... to a REDO of design education, to further research and the future fashion and textile industry....

  14. EVOLVING AN EMPIRICAL METHODOLOGY DOR DETERMINING ...

    African Journals Online (AJOL)

    The uniqueness of this approach, is that it can be applied to any forest or dynamic feature on the earth, and can enjoy universal application as well. KEY WORDS: Evolving empirical methodology, innovative mathematical model, appropriate interval, remote sensing, forest environment planning and management. Global Jnl ...

  15. Continual Learning through Evolvable Neural Turing Machines

    DEFF Research Database (Denmark)

    Lüders, Benno; Schläger, Mikkel; Risi, Sebastian

    2016-01-01

    Continual learning, i.e. the ability to sequentially learn tasks without catastrophic forgetting of previously learned ones, is an important open challenge in machine learning. In this paper we take a step in this direction by showing that the recently proposed Evolving Neural Turing Machine (ENTM...

  16. Did Language Evolve Like the Vertebrate Eye?

    Science.gov (United States)

    Botha, Rudolf P.

    2002-01-01

    Offers a critical appraisal of the way in which the idea that human language or some of its features evolved like the vertebrate eye by natural selection is articulated in Pinker and Bloom's (1990) selectionist account of language evolution. Argues that this account is less than insightful because it fails to draw some of the conceptual…

  17. Identification of dual-tropic HIV-1 using evolved neural networks.

    Science.gov (United States)

    Fogel, Gary B; Lamers, Susanna L; Liu, Enoch S; Salemi, Marco; McGrath, Michael S

    2015-11-01

    Blocking the binding of the envelope HIV-1 protein to immune cells is a popular concept for development of anti-HIV therapeutics. R5 HIV-1 binds CCR5, X4 HIV-1 binds CXCR4, and dual-tropic HIV-1 can bind either coreceptor for cellular entry. R5 viruses are associated with early infection and over time can evolve to X4 viruses that are associated with immune failure. Dual-tropic HIV-1 is less studied; however, it represents functional antigenic intermediates during the transition of R5 to X4 viruses. Viral tropism is linked partly to the HIV-1 envelope V3 domain, where the amino acid sequence helps dictate the receptor a particular virus will target; however, using V3 sequence information to identify dual-tropic HIV-1 isolates has remained difficult. Our goal in this study was to elucidate features of dual-tropic HIV-1 isolates that assist in the biological understanding of dual-tropism and develop an approach for their detection. Over 1559 HIV-1 subtype B sequences with known tropisms were analyzed. Each sequence was represented by 73 structural, biochemical and regional features. These features were provided to an evolved neural network classifier and evaluated using balanced and unbalanced data sets. The study resolved R5X4 viruses from R5 with an accuracy of 81.8% and from X4 with an accuracy of 78.8%. The approach also identified a set of V3 features (hydrophobicity, structural and polarity) that are associated with tropism transitions. The ability to distinguish R5X4 isolates will improve computational tropism decisions for R5 vs. X4 and assist in HIV-1 research and drug development efforts. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  18. Stereotactic radiotherapy for non-small cell lung cancer: From concept to clinical reality. 2011 update; Radiotherapie stereotaxique des cancers broncho-pulmonaires non a petites cellules: d'un concept a une realite clinique. Actualites en 2011

    Energy Technology Data Exchange (ETDEWEB)

    Girard, N. [Service de pneumologie, hopital Louis-Pradel, hospices civils de Lyon, 28, avenue du Doyen-Jean-Lepine, 69500 Bron (France); UMR 754, universite Claude-Bernard Lyon 1, 43, boulevard du 11-Novembre-1918, 69622 Villeurbanne cedex (France); Mornex, F. [Departement de radiotherapie oncologie, centre hospitalier Lyon-Sud, 165, chemin du Grand-Revoyet, 69495 Pierre-Benite cedex (France); EA 37-38, universite Claude-Bernard Lyon 1, 43, boulevard du 11-Novembre-1918, 69622 Villeurbanne cedex (France)

    2011-10-15

    Only 60% of patients with early-stage non-small cell lung cancer (NSCLC), a priori bearing a favorable prognosis, undergo radical resection because of the very frequent co-morbidities occurring in smokers, precluding surgery to be safely performed. Stereotactic radiotherapy consists of the use of multiple radiation micro-beams, allowing high doses of radiation to be delivered to the tumour (ranging from 7.5 to 20 Gy per fraction) in a small number of fractions (one to eight on average). Several studies with long-term follow-up are now available, showing the effectiveness of stereotactic radiotherapy to control stage I/II non-small cell lung cancer in medically inoperable patients. Local control rates are consistently reported to be above 95% with a median survival of 34 to 45 months. Because of these excellent results, stereotactic radiation therapy is now being evaluated in operable patients in several randomized trials with a surgical arm. Ultimately, the efficacy of stereotactic radiotherapy in early-stage tumours leads to hypothesize that it may represent an opportunity for locally-advanced tumors. The specific toxicities of stereotactic radiotherapy mostly correspond to radiation-induced chest wall side effects, especially for peripheral tumours. The use of adapted fractionation schemes has made feasible the use of stereotactic radiotherapy to treat proximal tumours. Overall, from a technical concept to the availability of specific treatment devices and the publication of clinical results, stereotactic radiotherapy represents a model of implementation in thoracic oncology. (authors)

  19. Wild Origins: The Evolving Nature of Animal Behavior

    Science.gov (United States)

    Flores, Ifigenia

    For billions of years, evolution has been the driving force behind the incredible range of biodiversity on our planet. Wild Origins is a concept plan for an exhibition at the National Zoo that uses case studies of animal behavior to explain the theory of evolution. Behaviors evolve, just as physical forms do. Understanding natural selection can help us interpret animal behavior and vice-versa. A living collection, digital media, interactives, fossils, and photographs will relay stories of social behavior, sex, navigation and migration, foraging, domestication, and relationships between different species. The informal learning opportunities visitors are offered at the zoo will create a connection with the exhibition's teaching points. Visitors will leave with an understanding and sense of wonder at the evolutionary view of life.

  20. The evolving block universe and the meshing together of times.

    Science.gov (United States)

    Ellis, George F R

    2014-10-01

    It has been proposed that spacetime should be regarded as an evolving block universe, bounded to the future by the present time, which continually extends to the future. This future boundary is defined at each time by measuring proper time along Ricci eigenlines from the start of the universe. A key point, then, is that physical reality can be represented at many different scales: hence, the passage of time may be seen as different at different scales, with quantum gravity determining the evolution of spacetime itself at the Planck scale, but quantum field theory and classical physics determining the evolution of events within spacetime at larger scales. The fundamental issue then arises as to how the effective times at different scales mesh together, leading to the concepts of global and local times. © 2014 New York Academy of Sciences.

  1. Experiences from Refurbishment of Metallography Hot Cells and Application of a New Preparation Concept for Materialography Samples

    International Nuclear Information System (INIS)

    Oberlander, B. C.; Espeland, M.; Solum, N. O.

    2001-01-01

    After more than 30 years of operation the lead shielded metallography hot cells needed a basic renewal and modernisation not least of the specimen preparation equipment. Preparation in hot cells of radioactive samples for metallography and ceramography is challenging and time consuming. It demands a special design and quality of all in-cell equipment and skill and patience from the operator. Essentials in the preparation process are: simplicity and reliability of the machines, and a good quality, reproducibility and efficiency in performance. Desirable is process automation, flexibility and an alara amounto of radioactive waste produced per sample prepared. State of the art preparation equipment for materialography seems to meet most of the demands, however, it cannot be used in hot cells without modifications. Therefore. IFE and Struers in Copenhagen modified a standard model of a Strues precision cutting machine and a microprocessor controlled grinding and polishing machine for Hot Cell application. Hot cell utilisation of the microcomputer controlled grinding and polishing machine and the existing automatic dosing equipment made the task of preparing radioactive samples more attractive. The new grinding and polishing system for hot cells provides good sample preparation quality and reproductibility at reduced preparation time and reduced amount of contaminated waste produced per sample prepared. the sample materials examined were irradiated cladding materials and fuels

  2. Investigation of a novel concept for hydrogen production by PEM water electrolysis integrated with multi-junction solar cells

    International Nuclear Information System (INIS)

    Ferrero, Domenico; Santarelli, Massimo

    2017-01-01

    Highlights: • A 2D model of a PEM water electrolyzer is developed and validated. • A novel system integrating PEM and multi-junction solar cells is proposed. • The model is applied to the simulation of the novel system. • The integration of PEM and MJ cells enhances the hydrogen production efficiency. - Abstract: A 2D finite element model of a high-pressure PEM water electrolyzer is developed and validated over experimental data obtained from a demonstration prototype. The model includes the electrochemical, fluidic and thermal description of the repeating unit of a PEM electrolyzer stack. The model is applied to the simulation of a novel system composed by a high-temperature, high-pressure PEM electrochemical cell coupled with a photovoltaic multi-junction solar cell installed in a solar concentrator. The thermo-electrochemical characterization of the solar-driven PEM electrolysis system is presented and the advantages of the high-temperature operation and of the direct coupling of electrolyzer and solar cell are assessed. The results show that the integration of the multi-junction cell enhances the performance of the electrolyzer and allows to achieve higher system efficiency compared to separated photovoltaic generation and hydrogen production by electrolysis.

  3. Development and the evolvability of human limbs

    OpenAIRE

    Young, Nathan M.; Wagner, Günter P.; Hallgrímsson, Benedikt

    2010-01-01

    The long legs and short arms of humans are distinctive for a primate, the result of selection acting in opposite directions on each limb at different points in our evolutionary history. This mosaic pattern challenges our understanding of the relationship of development and evolvability because limbs are serially homologous and genetic correlations should act as a significant constraint on their independent evolution. Here we test a developmental model of limb covariation in anthropoid primate...

  4. Quantum games on evolving random networks

    OpenAIRE

    Pawela, Łukasz

    2015-01-01

    We study the advantages of quantum strategies in evolutionary social dilemmas on evolving random networks. We focus our study on the two-player games: prisoner's dilemma, snowdrift and stag-hunt games. The obtained result show the benefits of quantum strategies for the prisoner's dilemma game. For the other two games, we obtain regions of parameters where the quantum strategies dominate, as well as regions where the classical strategies coexist.

  5. The Evolving Leadership Path of Visual Analytics

    Energy Technology Data Exchange (ETDEWEB)

    Kluse, Michael; Peurrung, Anthony J.; Gracio, Deborah K.

    2012-01-02

    This is a requested book chapter for an internationally authored book on visual analytics and related fields, coordianted by a UK university and to be published by Springer in 2012. This chapter is an overview of the leadship strategies that PNNL's Jim Thomas and other stakeholders used to establish visual analytics as a field, and how those strategies may evolve in the future.

  6. Evolving artificial metalloenzymes via random mutagenesis

    Science.gov (United States)

    Yang, Hao; Swartz, Alan M.; Park, Hyun June; Srivastava, Poonam; Ellis-Guardiola, Ken; Upp, David M.; Lee, Gihoon; Belsare, Ketaki; Gu, Yifan; Zhang, Chen; Moellering, Raymond E.; Lewis, Jared C.

    2018-03-01

    Random mutagenesis has the potential to optimize the efficiency and selectivity of protein catalysts without requiring detailed knowledge of protein structure; however, introducing synthetic metal cofactors complicates the expression and screening of enzyme libraries, and activity arising from free cofactor must be eliminated. Here we report an efficient platform to create and screen libraries of artificial metalloenzymes (ArMs) via random mutagenesis, which we use to evolve highly selective dirhodium cyclopropanases. Error-prone PCR and combinatorial codon mutagenesis enabled multiplexed analysis of random mutations, including at sites distal to the putative ArM active site that are difficult to identify using targeted mutagenesis approaches. Variants that exhibited significantly improved selectivity for each of the cyclopropane product enantiomers were identified, and higher activity than previously reported ArM cyclopropanases obtained via targeted mutagenesis was also observed. This improved selectivity carried over to other dirhodium-catalysed transformations, including N-H, S-H and Si-H insertion, demonstrating that ArMs evolved for one reaction can serve as starting points to evolve catalysts for others.

  7. Generalized concept of the LET-RBE relationship of radiation-induced chromosome aberration and cell death

    International Nuclear Information System (INIS)

    Takatsuji, Toshihiro; Yoshikawa, Isao; Sasaki, Masao S.

    1999-01-01

    The frequency of chromosome aberrations per traversal of a nucleus by a charged particle at the low dose limit increases proportionally to the square of the linear energy transfer (LET), peaks at about 100 keV/μm and then decreases with further increase of LET. This has long been interpreted as an excessive energy deposition over the necessary energy required to produce a biologically effective event. Here, we present an alternative interpretation. Cell traversed by a charged particle has certain probability to receive lethal damage leading to direct death. Such events may increase with an increase of LET and the number of charged particles traversing the cell. Assuming that the lethal damage is distributed according to a Poisson distribution, the probability that a cell has no such damage is expressed by e -cLx , where c is a constant, L is LET, and x is the number of charged particles traversing the cell. From these assumptions, the frequency of chromosome aberration in surviving cells can be described by Y=αSD+βS 2 D 2 with the empirical relation Y=αD+βD 2 in the low LET region, where S=e -cL , α is a value proportional to LET, β is a constant, and D is the absorbed dose. This model readily explains the empirically established relationship between LET and relative biological effectiveness (RBE). The model can also be applied to clonogenic survival. If cells can survive and they have neither unstable chromosome aberrations nor other lethal damage, the LET-RBE relationship for clonogenic survival forms a humped curve. The relationship between LET and inactivation cross-section becomes proportional to the square of LET in the low LET region when the frequency of a directly lethal events is sufficiently smaller than unity, and the inactivation cross-section saturates to the cell nucleus cross-sectional area with an increase in LET in the high LET region. (author)

  8. COMET concept

    International Nuclear Information System (INIS)

    Alsmeyer, H.; Tromm, W.

    1995-01-01

    Studies of the COMET core catcher concept developed for a future PWR have been continued. The concept is based on the spreading of a core melt on a sacrificial layer and its erosion, until a subsequent addition of water from below causes a fragmentation of the melt. A porous solidification of the melt would then admit a complete flooding within a short period. (orig.)

  9. Concept Mapping

    Science.gov (United States)

    Technology & Learning, 2005

    2005-01-01

    Concept maps are graphical ways of working with ideas and presenting information. They reveal patterns and relationships and help students to clarify their thinking, and to process, organize and prioritize. Displaying information visually--in concept maps, word webs, or diagrams--stimulates creativity. Being able to think logically teaches…

  10. Lateral Concepts

    DEFF Research Database (Denmark)

    Gad, Christopher; Bruun Jensen, casper

    2016-01-01

    This essay discusses the complex relation between the knowledges and practices of the researcher and his/her informants in terms of lateral concepts. The starting point is that it is not the prerogative of the (STS) scholar to conceptualize the world; all our “informants” do it too. This creates...... the possibility of enriching our own conceptual repertoires by letting them be inflected by the concepts of those we study. In a broad sense, the lateral means that there is a many-to-many relation between domains of knowledge and practice. However, each specific case of the lateral is necessarily immanent...... to a particular empirical setting and form of inquiry. In this sense lateral concepts are radically empirical since it locates concepts within the field. To clarify the meaning and stakes of lateral concepts, we first make a contrast between lateral anthropology and Latour’s notion of infra-reflexivity. We end...

  11. Concept theory

    DEFF Research Database (Denmark)

    Hjørland, Birger

    2009-01-01

      Concept theory is an extremely broad, interdisciplinary and complex field of research related to many deep fields with very long historical traditions without much consensus. However, information science and knowledge organization cannot avoid relating to theories of concepts. Knowledge...... organizing systems (e.g. classification systems, thesauri and ontologies) should be understood as systems basically organizing concepts and their semantic relations. The same is the case with information retrieval systems. Different theories of concepts have different implications for how to construe......, evaluate and use such systems. Based on "a post-Kuhnian view" of paradigms this paper put forward arguments that the best understanding and classification of theories of concepts is to view and classify them in accordance with epistemological theories (empiricism, rationalism, historicism and pragmatism...

  12. Evolving insights on metabolism, autophagy and epigenetics in liver myofibroblasts

    Directory of Open Access Journals (Sweden)

    Zeribe Chike Nwosu

    2016-06-01

    Full Text Available Liver myofibroblasts (MFB are crucial mediators of extracellular matrix (ECM deposition in liver fibrosis. They arise mainly from hepatic stellate cells (HSCs upon a process termed activation. To a lesser extent, and depending on the cause of liver damage, portal fibroblasts, mesothelial cells and fibrocytes may also contribute to the MFB population. Targeting MFB to reduce liver fibrosis is currently an area of intense research. Unfortunately, a clog in the wheel of antifibrotic therapies is the fact that although MFB are known to mediate scar formation, and participate in liver inflammatory response, many of their molecular portraits are currently unknown. In this review, we discuss recent understanding of MFB in health and diseases, focusing specifically on three evolving research fields: metabolism, autophagy and epigenetics. We have emphasized on therapeutic prospects where applicable and mentioned techniques for use in MFB studies. Subsequently, we highlighted uncharted territories in MFB research to help direct future efforts aimed at bridging gaps in current knowledge.

  13. Proof of concept of an epitaxy-free layer-transfer process for silicon solar cells based on the reorganisation of macropores upon annealing

    International Nuclear Information System (INIS)

    Depauw, V.; Gordon, I.; Beaucarne, G.; Poortmans, J.; Mertens, R.; Celis, J.-P.

    2009-01-01

    To answer the challenge of less expensive renewable electricity, the photovoltaics community is focusing on producing thinner silicon solar cells. A few years ago, in the field of silicon-on-nothing structures, micron-thick monocrystalline layers suspended over their parent wafer were produced by high-temperature annealing of specific arrays of macropores. Those macropores reorganise into one single void and leave a thin overlayer on top. Since this method may be an inexpensive way of fabricating high-quality silicon films, this paper investigates its potential for photovoltaic applications. In particular, we investigated if large surfaces can be produced and transferred to foreign substrates with this method. We fabricated basic solar cells, without rear-surface passivation, on 5 cm x 5 cm-large and 1-μm-thick films transferred to glass, that showed energy-conversion efficiencies up to 2.6%. These cells demonstrate the feasibility of the presented concept as a layer-transfer process for solar-cell application. After formation by annealing, the film is only barely attached to its parent wafer, but can still safely be handled provided that any abrupt gas flow or pumping to vacuum is avoided. After transfer and permanent bonding, the sample can be handled as any bulk wafer.

  14. Autologous transplantation of genetically modified iris pigment epithelial cells: A promising concept for the treatment of age-related macular degeneration and other disorders of the eye

    Science.gov (United States)

    Semkova, Irina; Kreppel, Florian; Welsandt, Gerhard; Luther, Thomas; Kozlowski, Jolanta; Janicki, Hanna; Kochanek, Stefan; Schraermeyer, Ulrich

    2002-10-01

    Age-related macular degeneration (ARMD) is the leading cause for visual impairment and blindness in the elder population. Laser photocoagulation, photodynamic therapy and excision of neovascular membranes have met with limited success. Submacular transplantation of autologous iris pigment epithelial (IPE) cells has been proposed to replace the damaged retinal pigment epithelium following surgical removal of the membranes. We tested our hypothesis that the subretinal transplantation of genetically modified autologous IPE cells expressing biological therapeutics might be a promising strategy for the treatment of ARMD and other retinal disorders. Pigment epithelium-derived factor (PEDF) has strong antiangiogenic and neuroprotective activities in the eye. Subretinal transplantation of PEDF expressing IPE cells inhibited pathological choroidal neovascularization in rat models of laser-induced rupture of Bruch's membrane and of oxygen induced ischemic retinopathy. PEDF expressing IPE transplants also increased the survival and preserved rhodopsin expression of photoreceptor cells in the RCS rat, a model of retinal degeneration. These findings suggest a promising concept for the treatment of ARMD and other retinal disorders.

  15. A Cell Internalizing Antibody Targeting Capsid Protein (p24 Inhibits the Replication of HIV-1 in T Cells Lines and PBMCs: A Proof of Concept Study.

    Directory of Open Access Journals (Sweden)

    Syed A Ali

    Full Text Available There remains a need for newer therapeutic approaches to combat HIV/AIDS. Viral capsid protein p24 plays important roles in HIV pathogenesis. Peptides and small molecule inhibitors targeting p24 have shown to inhibit virus replication in treated cell. High specificity and biological stability of monoclonal antibodies (mAbs make them an attractive contender for in vivo treatments. However, mAbs do not enter into cells, thus are restricted to target surface molecules. This also makes targeting intracellular HIV-1 p24 a challenge. A mAb specific to p24 that can internalize into the HIV-infected cells is hypothesized to inhibit the virus replication. We selected a mAb that has previously shown to inhibit p24 polymerization in an in vitro assay and chemically conjugated it with cell penetrating peptides (CPP to generate cell internalizing anti-p24 mAbs. Out of 8 CPPs tested, κFGF-MTS -conjugated mAbs internalized T cells most efficiently. At nontoxic concentration, the κFGF-MTS-anti-p24-mAbs reduced the HIV-1 replication up to 73 and 49% in T-lymphocyte and PBMCs respectively. Marked inhibition of HIV-1 replication in relevant cells by κFGF-MTS-anti-p24-mAbs represents a viable strategy to target HIV proteins present inside the cells.

  16. Haematopoietic stem cell transplantation as first-line treatment in myeloma: a global perspective of current concepts and future possibilities

    Directory of Open Access Journals (Sweden)

    Catriona Elizabeth Mactier

    2012-10-01

    Full Text Available Stem cell transplantation forms an integral part of the treatment for multiple myeloma. This paper reviews the current role of transplantation and the progress that has been made in order to optimize the success of this therapy. Effective induction chemotherapy is important and a combination regimen incorporating the novel agent bortezomib is now favorable. Adequate induction is a crucial adjunct to stem cell transplantation and in some cases may potentially postpone the need for transplant. Different conditioning agents prior to transplantation have been explored: high-dose melphalan is most commonly used and bortezomib is a promising additional agent. There is no well-defined superior transplantation protocol but single or tandem autologous stem cell transplantations are those most commonly used, with allogeneic transplantation only used in clinical trials. The appropriate timing of transplantation in the treatment plan is a matter of debate. Consolidation and maintenance chemotherapies, particularly thalidomide and bortezomib, aim to improve and prolong disease response to transplantation and delay recurrence. Prognostic factors for the outcome of stem cell transplant in myeloma have been highlighted. Despite good responses to chemotherapy and transplantation, the problem of disease recurrence persists. Thus, there is still much room for improvement. Treatments which harness the graft-versus-myeloma effect may offer a potential cure for this disease. Trials of novel agents are underway, including targeted therapies for specific antigens such as vaccines and monoclonal antibodies.

  17. Revealing evolved massive stars with Spitzer

    Science.gov (United States)

    Gvaramadze, V. V.; Kniazev, A. Y.; Fabrika, S.

    2010-06-01

    Massive evolved stars lose a large fraction of their mass via copious stellar wind or instant outbursts. During certain evolutionary phases, they can be identified by the presence of their circumstellar nebulae. In this paper, we present the results of a search for compact nebulae (reminiscent of circumstellar nebulae around evolved massive stars) using archival 24-μm data obtained with the Multiband Imaging Photometer for Spitzer. We have discovered 115 nebulae, most of which bear a striking resemblance to the circumstellar nebulae associated with luminous blue variables (LBVs) and late WN-type (WNL) Wolf-Rayet (WR) stars in the Milky Way and the Large Magellanic Cloud (LMC). We interpret this similarity as an indication that the central stars of detected nebulae are either LBVs or related evolved massive stars. Our interpretation is supported by follow-up spectroscopy of two dozen of these central stars, most of which turn out to be either candidate LBVs (cLBVs), blue supergiants or WNL stars. We expect that the forthcoming spectroscopy of the remaining objects from our list, accompanied by the spectrophotometric monitoring of the already discovered cLBVs, will further increase the known population of Galactic LBVs. This, in turn, will have profound consequences for better understanding the LBV phenomenon and its role in the transition between hydrogen-burning O stars and helium-burning WR stars. We also report on the detection of an arc-like structure attached to the cLBV HD 326823 and an arc associated with the LBV R99 (HD 269445) in the LMC. Partially based on observations collected at the German-Spanish Astronomical Centre, Calar Alto, jointly operated by the Max-Planck-Institut für Astronomie Heidelberg and the Instituto de Astrofísica de Andalucía (CSIC). E-mail: vgvaram@mx.iki.rssi.ru (VVG); akniazev@saao.ac.za (AYK); fabrika@sao.ru (SF)

  18. Evolving Random Forest for Preference Learning

    DEFF Research Database (Denmark)

    Abou-Zleikha, Mohamed; Shaker, Noor

    2015-01-01

    This paper introduces a novel approach for pairwise preference learning through a combination of an evolutionary method and random forest. Grammatical evolution is used to describe the structure of the trees in the Random Forest (RF) and to handle the process of evolution. Evolved random forests ...... obtained for predicting pairwise self-reports of users for the three emotional states engagement, frustration and challenge show very promising results that are comparable and in some cases superior to those obtained from state-of-the-art methods....

  19. An evolving network model with community structure

    International Nuclear Information System (INIS)

    Li Chunguang; Maini, Philip K

    2005-01-01

    Many social and biological networks consist of communities-groups of nodes within which connections are dense, but between which connections are sparser. Recently, there has been considerable interest in designing algorithms for detecting community structures in real-world complex networks. In this paper, we propose an evolving network model which exhibits community structure. The network model is based on the inner-community preferential attachment and inter-community preferential attachment mechanisms. The degree distributions of this network model are analysed based on a mean-field method. Theoretical results and numerical simulations indicate that this network model has community structure and scale-free properties

  20. Radio Imaging of Envelopes of Evolved Stars

    Science.gov (United States)

    Cotton, Bill

    2018-04-01

    This talk will cover imaging of stellar envelopes using radio VLBI techniques; special attention will be paid to the technical differences between radio and optical/IR interferomery. Radio heterodyne receivers allow a straightforward way to derive spectral cubes and full polarization observations. Milliarcsecond resolution of very bright, i.e. non thermal, emission of molecular masers in the envelopes of evolved stars can be achieved using VLBI techniques with baselines of thousands of km. Emission from SiO, H2O and OH masers are commonly seen at increasing distance from the photosphere. The very narrow maser lines allow accurate measurements of the velocity field within the emitting region.

  1. Mobile computing acceptance grows as applications evolve.

    Science.gov (United States)

    Porn, Louis M; Patrick, Kelly

    2002-01-01

    Handheld devices are becoming more cost-effective to own, and their use in healthcare environments is increasing. Handheld devices currently are being used for e-prescribing, charge capture, and accessing daily schedules and reference tools. Future applications may include education on medications, dictation, order entry, and test-results reporting. Selecting the right handheld device requires careful analysis of current and future applications, as well as vendor expertise. It is important to recognize the technology will continue to evolve over the next three years.

  2. Evolved Minimal Frustration in Multifunctional Biomolecules.

    Science.gov (United States)

    Röder, Konstantin; Wales, David J

    2018-05-25

    Protein folding is often viewed in terms of a funnelled potential or free energy landscape. A variety of experiments now indicate the existence of multifunnel landscapes, associated with multifunctional biomolecules. Here, we present evidence that these systems have evolved to exhibit the minimal number of funnels required to fulfil their cellular functions, suggesting an extension to the principle of minimum frustration. We find that minimal disruptive mutations result in additional funnels, and the associated structural ensembles become more diverse. The same trends are observed in an atomic cluster. These observations suggest guidelines for rational design of engineered multifunctional biomolecules.

  3. SALT Spectroscopy of Evolved Massive Stars

    Science.gov (United States)

    Kniazev, A. Y.; Gvaramadze, V. V.; Berdnikov, L. N.

    2017-06-01

    Long-slit spectroscopy with the Southern African Large Telescope (SALT) of central stars of mid-infrared nebulae detected with the Spitzer Space Telescope and Wide-Field Infrared Survey Explorer (WISE) led to the discovery of numerous candidate luminous blue variables (cLBVs) and other rare evolved massive stars. With the recent advent of the SALT fiber-fed high-resolution echelle spectrograph (HRS), a new perspective for the study of these interesting objects is appeared. Using the HRS we obtained spectra of a dozen newly identified massive stars. Some results on the recently identified cLBV Hen 3-729 are presented.

  4. Travelling Concepts

    DEFF Research Database (Denmark)

    Simonsen, Karen-Margrethe

    2013-01-01

    Review of "Travelling Concepts, Metaphors, and Narratives: Literary and Cultural Studies in an Age of Interdisciplinary Research" ed. by Sibylle Baumgarten, Beatrice Michaelis and Ansagar Nünning, Trier; Wissenschaftlicher Verlag Trier, 2012......Review of "Travelling Concepts, Metaphors, and Narratives: Literary and Cultural Studies in an Age of Interdisciplinary Research" ed. by Sibylle Baumgarten, Beatrice Michaelis and Ansagar Nünning, Trier; Wissenschaftlicher Verlag Trier, 2012...

  5. Novel concepts in electrochemical solar cells. Second quarterly progress report, August 15, 1979-October 15, 1979. [Molten salt electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    DuBow, J.; Job, R.; Krishnan, R.; Gale, B.

    1979-01-01

    It is considered that the short term stability of n-GaAs PEC's in a ferrocene-based, ambient temperature molten salt electrolyte is reasonably good. However, longer term evaluation is required to determine the extent and significance of corrosion, stability, etc. Extremely few fundamental studies have been made of the semiconductor/molten salt interphase and experiments in this area would be most useful. Indeed, even the design parameters for PECs of any kind have not been quantitatively delineated and present consideration will be given to models for PEC solar cells and limitations caused by ion transport in the electrolyte. The MoSe/sub 2/ and MoS/sub 2/ electrodes appear to have substrate reproducibility and transport limitations that make them unsuitable candidates for efficient PEC's at this time. Similarly, the lack of availability of high quality CuInSe/sub 2/ and CuInS/sub 2/ substrates limits the quantitative experimental evaluation of their utility for PEC applications. We are presently focusing attention on CdSe/CdTe mixtures and CdS as electrodes as well as Si and GaAs in molten salt and polyelectrolyte solutions. The system for solar cell evaluation and network analysis of substrates and cells was mode operational. Preliminary work on economic and theoretical modelling was begun. Progress is reported. (WHK)

  6. Folic acid induces cell type-specific changes in the transcriptome of breast cancer cell lines: a proof-of-concept study.

    Science.gov (United States)

    Price, R Jordan; Lillycrop, Karen A; Burdge, Graham C

    2016-01-01

    The effect of folic acid (FA) on breast cancer (BC) risk is uncertain. We hypothesised that this uncertainty may be due, in part, to differential effects of FA between BC cells with different phenotypes. To test this we investigated the effect of treatment with FA concentrations within the range of unmetabolised FA reported in humans on the expression of the transcriptome of non-transformed (MCF10A) and cancerous (MCF7 and Hs578T) BC cells. The total number of transcripts altered was: MCF10A, seventy-five (seventy up-regulated); MCF7, twenty-four (fourteen up-regulated); and Hs578T, 328 (156 up-regulated). Only the cancer-associated gene TAGLN was altered by FA in all three cell lines. In MCF10A and Hs578T cells, FA treatment decreased pathways associated with apoptosis, cell death and senescence, but increased those associated with cell proliferation. The folate transporters SLC19A1, SLC46A1 and FOLR1 were differentially expressed between cell lines tested. However, the level of expression was not altered by FA treatment. These findings suggest that physiological concentrations of FA can induce cell type-specific changes in gene regulation in a manner that is consistent with proliferative phenotype. This has implications for understanding the role of FA in BC risk. In addition, these findings support the suggestion that differences in gene expression induced by FA may involve differential activities of folate transporters. Together these findings indicate the need for further studies of the effect of FA on BC.

  7. BOOK REVIEW: OPENING SCIENCE, THE EVOLVING GUIDE ...

    Science.gov (United States)

    The way we get our funding, collaborate, do our research, and get the word out has evolved over hundreds of years but we can imagine a more open science world, largely facilitated by the internet. The movement towards this more open way of doing and presenting science is coming, and it is not taking hundreds of years. If you are interested in these trends, and would like to find out more about where this is all headed and what it means to you, consider downloding Opening Science, edited by Sönke Bartling and Sascha Friesike, subtitled The Evolving Guide on How the Internet is Changing Research, Collaboration, and Scholarly Publishing. In 26 chapters by various authors from a range of disciplines the book explores the developing world of open science, starting from the first scientific revolution and bringing us to the next scientific revolution, sometimes referred to as “Science 2.0”. Some of the articles deal with the impact of the changing landscape of how science is done, looking at the impact of open science on Academia, or journal publishing, or medical research. Many of the articles look at the uses, pitfalls, and impact of specific tools, like microblogging (think Twitter), social networking, and reference management. There is lots of discussion and definition of terms you might use or misuse like “altmetrics” and “impact factor”. Science will probably never be completely open, and Twitter will probably never replace the journal article,

  8. Evolving NASA's Earth Science Data Systems

    Science.gov (United States)

    Walter, J.; Behnke, J.; Murphy, K. J.; Lowe, D. R.

    2013-12-01

    NASA's Earth Science Data and Information System Project (ESDIS) is charged with managing, maintaining, and evolving NASA's Earth Observing System Data and Information System (EOSDIS) and is responsible for processing, archiving, and distributing NASA Earth science data. The system supports a multitude of missions and serves diverse science research and other user communities. Keeping up with ever-changing information technology and figuring out how to leverage those changes across such a large system in order to continuously improve and meet the needs of a diverse user community is a significant challenge. Maintaining and evolving the system architecture and infrastructure is a continuous and multi-layered effort. It requires a balance between a "top down" management paradigm that provides a coherent system view and maintaining the managerial, technological, and functional independence of the individual system elements. This presentation will describe some of the key elements of the current system architecture, some of the strategies and processes we employ to meet these challenges, current and future challenges, and some ideas for meeting those challenges.

  9. The Comet Cometh: Evolving Developmental Systems.

    Science.gov (United States)

    Jaeger, Johannes; Laubichler, Manfred; Callebaut, Werner

    In a recent opinion piece, Denis Duboule has claimed that the increasing shift towards systems biology is driving evolutionary and developmental biology apart, and that a true reunification of these two disciplines within the framework of evolutionary developmental biology (EvoDevo) may easily take another 100 years. He identifies methodological, epistemological, and social differences as causes for this supposed separation. Our article provides a contrasting view. We argue that Duboule's prediction is based on a one-sided understanding of systems biology as a science that is only interested in functional, not evolutionary, aspects of biological processes. Instead, we propose a research program for an evolutionary systems biology, which is based on local exploration of the configuration space in evolving developmental systems. We call this approach-which is based on reverse engineering, simulation, and mathematical analysis-the natural history of configuration space. We discuss a number of illustrative examples that demonstrate the past success of local exploration, as opposed to global mapping, in different biological contexts. We argue that this pragmatic mode of inquiry can be extended and applied to the mathematical analysis of the developmental repertoire and evolutionary potential of evolving developmental mechanisms and that evolutionary systems biology so conceived provides a pragmatic epistemological framework for the EvoDevo synthesis.

  10. Novel Concept of CD4-Mediated Activation of Regulatory T Cells for the Treatment of Graft-Versus-Host Disease

    Directory of Open Access Journals (Sweden)

    Janine Schlöder

    2017-11-01

    Full Text Available Allogeneic hematopoietic stem cell transplantation is the only curative treatment option for several hematological malignancies and immune deficiency syndromes. Nevertheless, the development of a graft-versus-host disease (GvHD after transplantation is a high risk and a severe complication with high morbidity and mortality causing therapeutic challenges. Current pharmacological therapies of GvHD lead to generalized immunosuppression followed by severe adverse side effects including infections and relapse of leukemia. Several novel cell-based immunomodulatory strategies for treatment or prevention of GvHD have been developed. Herein, thymus-derived regulatory T cells (tTreg, essential for the maintenance of peripheral immunologic tolerance, are in the focus of investigation. However, due to the limited number of tTreg in the peripheral blood, a complex, time- and cost-intensive in vitro expansion protocol is necessary for the production of an efficient cellular therapeutic. We demonstrated that activation of tTreg using the CD4-binding human immunodeficiency virus-1 protein gp120 leads to a substantially increased suppressor activity of tTreg without the need for additional expansion. Gp120-activated tTreg prevent GvHD development in a preclinical humanized mouse model. In addition, gp120 is not only effective in prevention but also in therapy of GvHD by suppressing all clinical symptoms and improving survival of treated mice. These data indicate that tTreg activation by gp120 is a feasible and potent strategy for significant functional improvement of tTreg as cellular therapeutic for GvHD treatment without the need of complicated, time-intensive, and expensive in vitro expansion of isolated tTreg.

  11. Concepts and challenges in the use of mesenchymal stem cells as a treatment for cartilage damage in the horse.

    Science.gov (United States)

    Zayed, Mohammed; Adair, Steve; Ursini, Tena; Schumacher, James; Misk, Nabil; Dhar, Madhu

    2018-03-20

    Osteoarthritis (OA), the most common form of joint disease affecting humans and horses, is characterized by the advance and decline of cartilage and loss of function of the affected joint. The progression of OA is steadily accompanied with biochemical events, which interfere with the cytokines and proteolytic enzymes responsible for progress of the disease. Recently, regenerative therapies have been used with an assumption that mesenchymal stem cells (MSCs) possess the potential to prevent the advancement of cartilage damage and potentially regenerate the injured tissue with an ultimate goal of preventing OA. We believe that despite various challenges, the use of allogenic versus autologous MSCs in cartilage regeneration, is a major issue which can directly or indirectly affect the other factors including, the timing of implantation, dose or cell numbers for implantation, and the source of MSCs. Current knowledge reporting some of these challenges that the clinicians might face in the treatment of cartilage damage in horses are presented. In this regard we conducted two independent studies. In the first study we compared donor matched bone marrow and synovial fluid - derived equine MSCs in vitro, and showed that the SFMSCs were similar to the BMMSCs in their proliferation, expression of CD29, CD44 and CD90, but, exhibited a significantly different chondrogenesis. Additionally, 3.2-21% of all SFMSCs were positive for MHC II, whereas, BMMSCs were negative. In the second study we observed that injection of both the autologous and allogenic SFMSCs into the tarsocrural joint resulted in elevated levels of total protein and total nucleated cell counts. Further experiments to evaluate the in vivo acute or chronic response to allogenic or autologous MSCs are imperative. Copyright © 2018 Elsevier Ltd. All rights reserved.

  12. Discarded cell phone lithium ion batteries state of health quick method analysis by galvanostatic intermittent titration technique (GITT concept

    Directory of Open Access Journals (Sweden)

    Paulo Rogério Catarini

    2009-03-01

    Full Text Available The state of health (SOH is a important evaluation parameter to rechargeable batteries, because determine its cycle life and help on electric devices supplied by batteries maintenance. In this work the lithium ion discards cell phones batteries state of health and apparent diffusion coefficient (Dap were measured and correlated which purpose is diminish the batteries analyze time. The apparent diffusion coefficient is a ionic diffusion coefficient modification from GITT technique. The SOH and Dap correlation is well behaved, disclosing a cubic dependency. The time analyze was reduced by more than 1 h.

  13. Proof of the concept to use a malignant B cell line drug screen strategy for identification and weight of melphalan resistance genes in multiple myeloma.

    Directory of Open Access Journals (Sweden)

    Martin Bøgsted

    Full Text Available In a conceptual study of drug resistance we have used a preclinical model of malignant B-cell lines by combining drug induced growth inhibition and gene expression profiling. In the current report a melphalan resistance profile of 19 genes were weighted by microarray data from the MRC Myeloma IX trial and time to progression following high dose melphalan, to generate an individual melphalan resistance index. The resistance index was subsequently validated in the HOVON65/GMMG-HD4 trial data set to prove the concept. Biologically, the assigned resistance indices were differentially distributed among translocations and cyclin D expression classes. Clinically, the 25% most melphalan resistant, the intermediate 50% and the 25% most sensitive patients had a median progression free survival of 18, 32 and 28 months, respectively (log-rank P-value  = 0.05. Furthermore, the median overall survival was 45 months for the resistant group and not reached for the intermediate and sensitive groups (log-rank P-value  = 0.003 following 38 months median observation. In a multivariate analysis, correcting for age, sex and ISS-staging, we found a high resistance index to be an independent variable associated with inferior progression free survival and overall survival. This study provides clinical proof of concept to use in vitro drug screen for identification of melphalan resistance gene signatures for future functional analysis.

  14. Cell therapy in the treatment of bipolar mania in an animal model: a proof of concept study

    Directory of Open Access Journals (Sweden)

    Bruna M. Ascoli

    2017-05-01

    Full Text Available Abstract Introduction The rationale of mesenchymal stem cells (MSCs as a novel therapeutic approach in certain neurodegenerative diseases is based on their ability to promote neurogenesis. Hippocampal atrophy has been related to bipolar disorder (BD in preclinical, imaging and postmortem studies. Therefore, the development of new strategies to stimulate the neurogenesis process in BD is crucial. Objectives To investigate the behavioral and neurochemical changes induced by transplantation of MSCs in a model of mania-like behavior induced by lisdexamfetamine dimesylate (LDX. Methods Wistar rats (n=65 received one oral daily dose of LDX (10 mg/kg or saline for 14 days. On the 8th day of treatment, the animals additionally received intrahippocampal saline or MSC (1 µL containing 25,000 cells or lithium (47.5 mg/kg as an internal experimental control. Two hours after the last administration, behavioral and neurochemical analyses were performed. Results LDX-treated rats had increased locomotor activity compared to saline-saline rats (p=0.004, and lithium reversed LDX-related hyperactive behavior (p0.05 in the hippocampus of rats. Conclusion Even though these results suggest that a single intrahippocampal injection of MSCs was not helpful to treat hyperactivity induced by LDX and neither influenced BDNF secretion, we cannot rule out the possible therapeutic effects of MSCs. Further research is required to determine direct effects of LDX on brain structures as well as in other pathophysiological targets related to BD.

  15. Role of intermediate metallic sub-layers in improving the efficiency of kesterite solar cells: concept and optimization

    Science.gov (United States)

    Ferhati, H.; Djeffal, F.

    2018-03-01

    In this work, versatile CdS/Cu 2 ZnSnS 4 (CZTS) solar cell designs based on intermediate metallic sub-layers (Au, Ti, and Ag) engineering are proposed for enhancing light-scattering behavior and reducing recombination losses. The idea behind this work is to generate optical confinement regions in the CZTS absorber layer to achieve an improved absorption and appropriate antireflection effects. Moreover, the ultra-thin metal at the CZTS/Mo interface can be helpful for reducing the series resistance, where it behaves like a blocking layer for the Sulfur diffusion. We further combine the proposed designs with Particle Swarm Optimization (PSO)-based approach to achieve broadband absorption and boost the conversion efficiency. It is found that the optimized design with Ti sub-layer improves the CZTS solar cell properties, where it yields 31% improvement in short-circuit current and 60% in the power efficiency over the conventional one. Therefore, the optimized designs provide the opportunity for bridging the gap between improving the optical behavior and reducing the recombination losses.

  16. Adaptation to acrolein through upregulating the protection by glutathione in human bronchial epithelial cells: the materialization of the hormesis concept.

    Science.gov (United States)

    Sthijns, Mireille M J P E; Randall, Matthew J; Bast, Aalt; Haenen, Guido R M M

    2014-04-18

    Acrolein is a thiol reactive compound present in cigarette smoke and plays a pivotal role in the deleterious effects of smoking. Acrolein causes toxicity in human bronchial epithelial cells in a dose dependent manner. GSH forms the first line of defense against acrolein-induced toxicity. At high doses of acrolein (⩾10 μM) the capacity of the cellular protection by GSH is overwhelmed and GSH is not able to quench all the acrolein, resulting in cytotoxicity. At a relatively low dose of acrolein (3 μM), no cytotoxicity is observed due to protection by GSH. Moreover we found that exposure to a low dose of acrolein protects cells against the toxic effect of a second higher dose of acrolein. The adaptation to acrolein is induced via Nrf2 mediated gene expression of γ-glutamylcysteine synthetase leading to elevated GSH levels. This upregulation of the protection by GSH demonstrates a hormetic response to acrolein. Hormesis is an adaptive or compensatory response induced by a relatively subtle challenge of homeostasis by a toxic compound. Insight into the mechanism of hormesis is mandatory for a more accurate societal regulation of toxic compounds. Copyright © 2014 Elsevier Inc. All rights reserved.

  17. Conceptional design of a novel next-generation cryogenic stopping cell for the Low-Energy Branch of the Super-FRS

    Energy Technology Data Exchange (ETDEWEB)

    Dickel, T., E-mail: t.dickel@gsi.de [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt (Germany); Plaß, W.R.; Geissel, H. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt (Germany); Heiße, F. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt (Germany); Institut für Kern- und Teilchenphysik, Technische Universität Dresden, Dresden (Germany); Miskun, I. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); Purushothman, S. [GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt (Germany); Reiter, M.P.; Rink, A.-K. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); Scheidenberger, C. [II. Physikalisches Institut, Justus-Liebig-Universität Gießen, Gießen (Germany); GSI Helmholtzzentrum für Schwerionenforschung GmbH, Darmstadt (Germany)

    2016-06-01

    The conceptual design of a next-generation cryogenic stopping cell (CSC) for the Low-Energy Branch (LEB) of the Super-FRS has been developed. It builds on advanced techniques implemented in the prototype version of the CSC, which has recently been commissioned as part of the FRS Ion Catcher with {sup 238}U projectile and fission fragments produced at 1000 MeV/u. These techniques include cryogenic operation to ensure a high purity of the stopping gas and high-density operation enabled using an RF carpet with a small electrode structure size. The next generation CSC implements several novel concepts (e.g. perpendicular extraction) which lead to enhanced performance compared to the prototype CSC: (i) extremely short extraction times, (ii) higher rate capability, (iii) increased areal density without deteriorating extraction times, efficiencies or rate capability, (iv) minimized RF power, (v) precise range measurement of the ions and (vii) improved cleanliness of the CSC.

  18. GRI: focusing on the evolving violent universe

    DEFF Research Database (Denmark)

    Knodlseder, J.; von Ballmoos, P.; Frontera, F.

    2009-01-01

    The gamma-ray imager (GRI) is a novel mission concept that will provide an unprecedented sensitivity leap in the soft gamma-ray domain by using for the first time a focusing lens built of Laue diffracting crystals. The lens will cover an energy band from 200-1,300 keV with an effective area reach...... processes in the universe....

  19. Sepiolite as a New Nanocarrier for DNA Transfer into Mammalian Cells: Proof of Concept, Issues and Perspectives.

    Science.gov (United States)

    Piétrement, Olivier; Castro-Smirnov, Fidel Antonio; Le Cam, Eric; Aranda, Pilar; Ruiz-Hitzky, Eduardo; Lopez, Bernard S

    2017-12-29

    Sepiolite is a nanofibrous natural silicate that can be used as a nanocarrier for DNA transfer thanks to its strong interaction with DNA molecules and its ability to be naturally internalized into mammalian cells through both non-endocytic and endocytic pathways. Sepiolite, due to its ability to bind various biomolecules, could be a good candidate for use as a nanocarrier for the simultaneous vectorization of diverse biological molecules. In this paper, we review our recent work, issued from a starting collaboration with Prof. Ruiz-Hitzky, that includes diverse aspects on the characterization and main features of sepiolite/DNA nanohybrids, and we present an outlook for the further development of sepiolite for DNA transfer. © 2017 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Selfish cells in altruistic cell society - a theoretical oncology.

    Science.gov (United States)

    Chigira, M

    1993-09-01

    In multicellular organisms, internal evolution of individual cells is strictly forbidden and 'evolutional' DNA replication should be performed only by the sexual reproduction system. Wholistic negative control system called 'homeostasis' serves all service to germ line cells. All somatic cells are altruistic to the germ line cells. However, in malignant tumors, it seems that individual cells replicate and behave 'selfishly' and evolve against the internal microenvironment. Tumor cells only express the occult selfishness which is programmed in normal cells a priori. This phenomenon is based on the failure of identical DNA replication, and results in 'autonomy' and 'anomie' of cellular society as shown in tumor cells. Genetic programs of normal cells connote this cellular autonomy and anomie introduced by the deletion of regulators on structure genes. It is rather paradoxical that the somatic cells get their freedom from wholistic negative regulation programmed internally. However, this is not a true paradox, since multicellular organisms have clearly been evolved from 'monads' in which cells proliferate without wholistic regulation. Somatic cells revolt against germ cell DNA, called 'selfish replicator' by Dawkins. It is an inevitable destiny that the 'selfishness' coded in genome should be revenged by itself. Selfish replicator in germ cell line should be revolted by its selfishness in the expansion of somatic cells, since they have an orthogenesis to get more selfishness in order to increase their genome. Tumor heterogeneity and progression can be fully explained by this self-contradictory process which produces heterogeneous gene copies different from the original clone in the tumor, although 'selfish' gene replication is the final target of being. Furthermore, we have to discard the concept of clonality of tumor cells since genetic instability is a fundamental feature of tumors. Finally, tumor cells and proto-oncogenes can be considered as the ultimate parasite

  1. Evolving colon injury management: a review.

    Science.gov (United States)

    Greer, Lauren T; Gillern, Suzanne M; Vertrees, Amy E

    2013-02-01

    The colon is the second most commonly injured intra-abdominal organ in penetrating trauma. Management of traumatic colon injuries has evolved significantly over the past 200 years. Traumatic colon injuries can have a wide spectrum of severity, presentation, and management options. There is strong evidence that most non-destructive colon injuries can be successfully managed with primary repair or primary anastomosis. The management of destructive colon injuries remains controversial with most favoring resection with primary anastomosis and others favor colonic diversion in specific circumstances. The historical management of traumatic colon injuries, common mechanisms of injury, demographics, presentation, assessment, diagnosis, management, and complications of traumatic colon injuries both in civilian and military practice are reviewed. The damage control revolution has added another layer of complexity to management with continued controversy.

  2. Pulmonary Sporotrichosis: An Evolving Clinical Paradigm.

    Science.gov (United States)

    Aung, Ar K; Spelman, Denis W; Thompson, Philip J

    2015-10-01

    In recent decades, sporotrichosis, caused by thermally dimorphic fungi Sporothrix schenckii complex, has become an emerging infection in many parts of the world. Pulmonary infection with S. schenckii still remains relatively uncommon, possibly due to underrecognition. Pulmonary sporotrichosis presents with distinct clinical and radiological patterns in both immunocompetent and immunocompromised hosts and can often result in significant morbidity and mortality despite treatment. Current understanding regarding S. schenckii biology, epidemiology, immunopathology, clinical diagnostics, and treatment options has been evolving in the recent years with increased availability of molecular sequencing techniques. However, this changing knowledge has not yet been fully translated into a better understanding of the clinical aspects of pulmonary sporotrichosis, as such current management guidelines remain unsupported by high-level clinical evidence. This article examines recent advances in the knowledge of sporotrichosis and its application to the difficult challenges of managing pulmonary sporotrichosis. Thieme Medical Publishers 333 Seventh Avenue, New York, NY 10001, USA.

  3. Resiliently evolving supply-demand networks

    Science.gov (United States)

    Rubido, Nicolás; Grebogi, Celso; Baptista, Murilo S.

    2014-01-01

    The ability to design a transport network such that commodities are brought from suppliers to consumers in a steady, optimal, and stable way is of great importance for distribution systems nowadays. In this work, by using the circuit laws of Kirchhoff and Ohm, we provide the exact capacities of the edges that an optimal supply-demand network should have to operate stably under perturbations, i.e., without overloading. The perturbations we consider are the evolution of the connecting topology, the decentralization of hub sources or sinks, and the intermittence of supplier and consumer characteristics. We analyze these conditions and the impact of our results, both on the current United Kingdom power-grid structure and on numerically generated evolving archetypal network topologies.

  4. Development and the evolvability of human limbs.

    Science.gov (United States)

    Young, Nathan M; Wagner, Günter P; Hallgrímsson, Benedikt

    2010-02-23

    The long legs and short arms of humans are distinctive for a primate, the result of selection acting in opposite directions on each limb at different points in our evolutionary history. This mosaic pattern challenges our understanding of the relationship of development and evolvability because limbs are serially homologous and genetic correlations should act as a significant constraint on their independent evolution. Here we test a developmental model of limb covariation in anthropoid primates and demonstrate that both humans and apes exhibit significantly reduced integration between limbs when compared to quadrupedal monkeys. This result indicates that fossil hominins likely escaped constraints on independent limb variation via reductions to genetic pleiotropy in an ape-like last common ancestor (LCA). This critical change in integration among hominoids, which is reflected in macroevolutionary differences in the disparity between limb lengths, facilitated selection for modern human limb proportions and demonstrates how development helps shape evolutionary change.

  5. Evolving spiking networks with variable resistive memories.

    Science.gov (United States)

    Howard, Gerard; Bull, Larry; de Lacy Costello, Ben; Gale, Ella; Adamatzky, Andrew

    2014-01-01

    Neuromorphic computing is a brainlike information processing paradigm that requires adaptive learning mechanisms. A spiking neuro-evolutionary system is used for this purpose; plastic resistive memories are implemented as synapses in spiking neural networks. The evolutionary design process exploits parameter self-adaptation and allows the topology and synaptic weights to be evolved for each network in an autonomous manner. Variable resistive memories are the focus of this research; each synapse has its own conductance profile which modifies the plastic behaviour of the device and may be altered during evolution. These variable resistive networks are evaluated on a noisy robotic dynamic-reward scenario against two static resistive memories and a system containing standard connections only. The results indicate that the extra behavioural degrees of freedom available to the networks incorporating variable resistive memories enable them to outperform the comparative synapse types.

  6. Argentina and Brazil: an evolving nuclear relationship

    International Nuclear Information System (INIS)

    Redick, J.R.

    1990-01-01

    Argentina and Brazil have Latin America's most advanced nuclear research and power programs. Both nations reject the Non-Proliferation Treaty (NPT), and have not formally embraced the Tlatelolco Treaty creating a regional nuclear-weapon-free zone. Disturbing ambiguities persist regarding certain indigenous nuclear facilities and growing nuclear submarine and missile capabilities. For these, and other reasons, the two nations are widely considered potential nuclear weapon states. However both nations have been active supporters of the International Atomic Energy Agency (IAEA) and have, in recent years, assumed a generally responsible position in regard to their own nuclear export activities (requiring IAEA safeguards). Most important, however, has been the advent of bilateral nuclear cooperation. This paper considers the evolving nuclear relationship in the context of recent and dramatic political change in Argentina and Brazil. It discusses current political and nuclear developments and the prospects for maintaining and expanding present bilateral cooperation into an effective non-proliferation arrangement. (author)

  7. Evolving the use of peptides as biomaterials components

    Science.gov (United States)

    Collier, Joel H.; Segura, Tatiana

    2012-01-01

    This manuscript is part of a debate on the statement that “the use of short synthetic adhesion peptides, like RGD, is the best approach in the design of biomaterials that guide cell behavior for regenerative medicine and tissue engineering”. We take the position that although there are some acknowledged disadvantages of using short peptide ligands within biomaterials, it is not necessary to discard the notion of using peptides within biomaterials entirely, but rather to reinvent and evolve their use. Peptides possess advantageous chemical definition, access to non-native chemistries, amenability to de novo design, and applicability within parallel approaches. Biomaterials development programs that require such aspects may benefit from a peptide-based strategy. PMID:21515167

  8. The genotype-phenotype map of an evolving digital organism

    OpenAIRE

    Fortuna, Miguel A.; Zaman, Luis; Ofria, Charles; Wagner, Andreas

    2017-01-01

    To understand how evolving systems bring forth novel and useful phenotypes, it is essential to understand the relationship between genotypic and phenotypic change. Artificial evolving systems can help us understand whether the genotype-phenotype maps of natural evolving systems are highly unusual, and it may help create evolvable artificial systems. Here we characterize the genotype-phenotype map of digital organisms in Avida, a platform for digital evolution. We consider digital organisms fr...

  9. The Evolving Science of Patient and Family Engagement: An Interview With Dr Karen Drenkard.

    Science.gov (United States)

    Reid-Ponte, Patricia

    2018-02-01

    Patient- and family-centered care is a central tenet of nursing practice. This concept has evolved to include patient partnerships, patient engagement, and patient activation. This column differentiates these concepts and describes the core principles embedded in the overriding intention of ensuring that patients (and their families or significant others) are orchestrators of their health and their care plans. In this interview, Karen Drenkard, PhD, RN, FAAN, NEA-BC, CNO, of the GetWellNetwork, discusses work by the O'Neil Center as a leader in this area.

  10. Contemporary conceptions of etiology, pathogenesis, management and treatment of primary diffuse large b-cell central nervous system lymphoma

    Directory of Open Access Journals (Sweden)

    S. V. Voloshin

    2013-01-01

    Full Text Available In this article we present the most up-to-date information about etiology, pathogenesis, diagnostic and treatment principles of primary central nervous system diffuse large B-cell lymphoma. We propose algorithm of diagnosis and treatment based on literature review and own experience. The main methods for diagnosis verification are magneto-resonance tomography and stereotactic biopsy of mass with subsequent histological examination including immune staining. The common first-line therapy regimen is high-dose methotrexate therapy. However long-term prognosis still remains poor. Adverse prognostic factors for therapy response are age > 60 years, multifocal lesions, neurologic symptoms,previous treated disease. Considerable part of patient have contraindications or high-risk of adverse events for high-dose chemotherapy treatment. Anti-CD20 monoclonal antibody has no neurological toxicity with intravenous and intrathecal administrations. Combination therapy with reduced dose methotrexate and monoclonal antibody can be a reasonable treatment alternative for old and disable persons. The further survival improvement would be achieved by patient stratification and using of risk-adapted treatment algorithm. 

  11. Contemporary conceptions of etiology, pathogenesis, management and treatment of primary diffuse large b-cell central nervous system lymphoma

    Directory of Open Access Journals (Sweden)

    S. V. Voloshin

    2014-07-01

    Full Text Available In this article we present the most up-to-date information about etiology, pathogenesis, diagnostic and treatment principles of primary central nervous system diffuse large B-cell lymphoma. We propose algorithm of diagnosis and treatment based on literature review and own experience. The main methods for diagnosis verification are magneto-resonance tomography and stereotactic biopsy of mass with subsequent histological examination including immune staining. The common first-line therapy regimen is high-dose methotrexate therapy. However long-term prognosis still remains poor. Adverse prognostic factors for therapy response are age > 60 years, multifocal lesions, neurologic symptoms,previous treated disease. Considerable part of patient have contraindications or high-risk of adverse events for high-dose chemotherapy treatment. Anti-CD20 monoclonal antibody has no neurological toxicity with intravenous and intrathecal administrations. Combination therapy with reduced dose methotrexate and monoclonal antibody can be a reasonable treatment alternative for old and disable persons. The further survival improvement would be achieved by patient stratification and using of risk-adapted treatment algorithm. 

  12. Models for mature T-cell lymphomas--a critical appraisal of experimental systems and their contribution to current T-cell tumorigenic concepts.

    Science.gov (United States)

    Warner, Kathrin; Crispatzu, Giuliano; Al-Ghaili, Nabil; Weit, Nicole; Florou, Vaia; You, M James; Newrzela, Sebastian; Herling, Marco

    2013-12-01

    Mature T-cell lymphomas/leukemias (MTCL) have been understudied lymphoid neoplasms that currently receive growing attention. Our historically rudimentary molecular understanding and dissatisfactory interventional success in this complex and for the most part poor-prognostic group of tumors is only slightly improving. A major limiting aspect in further progress in these rare neoplasms is the lack of suitable model systems that would substantially facilitate pathogenic studies and pre-clinical drug evaluations. Such representations of MTCL have thus far not been systematically appraised. We therefore provide an overview on existing models and point out their particular advantages and limitations in the context of the specific scientific questions. After addressing issues of species-specific differences and classifications, we summarize data on MTCL cell lines of human as well as murine origin, on murine strain predispositions to MTCL, on available models of genetically engineered mice, and on transplant systems. From an in-silico meta-analysis of available primary data of gene expression profiles on human MTCL we cross-reference genes reported to transform T-cells in mice and reflect on their general vs entity-restricted relevance and on target-promoter influences. Overall, we identify the urgent need for new models of higher fidelity to human MTCL with respect to their increasingly recognized diversity and to predictions of drug response. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  13. Basic concepts

    International Nuclear Information System (INIS)

    Dorner, B.

    1999-01-01

    The basic concepts of neutron scattering as a tool for studying the structure and the dynamics of condensed matter. Theoretical aspects are outlined, the two different cases of coherent and incoherent scattering are presented. The issue of resolution, coherence volume and the role of monochromators are also discussed. (K.A.)

  14. Simple Concepts

    Czech Academy of Sciences Publication Activity Database

    Materna, Pavel

    2013-01-01

    Roč. 28, č. 3 (2013), s. 295-319 ISSN 0353-5150 R&D Projects: GA ČR(CZ) GAP401/10/0792 Institutional support: RVO:67985955 Keywords : concept * constructions * set-theoretical paradigm Subject RIV: AA - Philosophy ; Religion

  15. Macroscopic Theory for Evolving Biological Systems Akin to Thermodynamics.

    Science.gov (United States)

    Kaneko, Kunihiko; Furusawa, Chikara

    2018-05-20

    We present a macroscopic theory to characterize the plasticity, robustness, and evolvability of biological responses and their fluctuations. First, linear approximation in intracellular reaction dynamics is used to demonstrate proportional changes in the expression of all cellular components in response to a given environmental stress, with the proportion coefficient determined by the change in growth rate as a consequence of the steady growth of cells. We further demonstrate that this relationship is supported through adaptation experiments of bacteria, perhaps too well as this proportionality is held even across cultures of different types of conditions. On the basis of simulations of cell models, we further show that this global proportionality is a consequence of evolution in which expression changes in response to environmental or genetic perturbations are constrained along a unique one-dimensional curve, which is a result of evolutionary robustness. It then follows that the expression changes induced by environmental changes are proportionally reduced across different components of a cell by evolution, which is akin to the Le Chatelier thermodynamics principle. Finally, with the aid of a fluctuation-response relationship, this proportionality is shown to hold between fluctuations caused by genetic changes and those caused by noise. Overall, these results and support from the theoretical and experimental literature suggest a formulation of cellular systems akin to thermodynamics, in which a macroscopic potential is given by the growth rate (or fitness) represented as a function of environmental and evolutionary changes.

  16. Whole-cell bioreporters and risk assessment of environmental pollution: A proof-of-concept study using lead.

    Science.gov (United States)

    Zhang, Xiaokai; Qin, Boqiang; Deng, Jianming; Wells, Mona

    2017-10-01

    As the world burden of environmental contamination increases, it is of the utmost importance to develop streamlined approaches to environmental risk assessment in order to prioritize mitigation measures. Whole-cell biosensors or bioreporters and speciation modeling have both become of increasing interest to determine the bioavailability of pollutants, as bioavailability is increasingly in use as an indicator of risk. Herein, we examine whether bioreporter results are able to reflect expectations based on chemical reactivity and speciation modeling, with the hope to extend the research into a wider framework of risk assessment. We study a specific test case concerning the bioavailability of lead (Pb) in aqueous environments containing Pb-complexing ligands. Ligands studied include ethylene diamine tetra-acetic acid (EDTA), meso-2,3 dimercaptosuccinic acid (DMSA), leucine, methionine, cysteine, glutathione, and humic acid (HA), and we also performed experiments using natural water samples from Lake Tai (Taihu), the third largest lake in China. We find that EDTA, DMSA, cysteine, glutathione, and HA amendment significantly reduced Pb bioavailability with increasing ligand concentration according to a log-sigmoid trend. Increasing dissolved organic carbon in Taihu water also had the same effect, whereas leucine and methionine had no notable effect on bioavailability at the concentrations tested. We find that bioreporter results are in accord with the reduction of aqueous Pb 2+ that we expect from the relative complexation affinities of the different ligands tested. For EDTA and HA, for which reasonably accurate ionization and complexation constants are known, speciation modeling is in agreement with bioreporter response to within the level of uncertainty recognised as reasonable by the United States Environmental Protection Agency for speciation-based risk assessment applications. These findings represent a first step toward using bioreporter technology to streamline

  17. Whole-cell bioreporters and risk assessment of environmental pollution: A proof-of-concept study using lead

    International Nuclear Information System (INIS)

    Zhang, Xiaokai; Qin, Boqiang; Deng, Jianming; Wells, Mona

    2017-01-01

    As the world burden of environmental contamination increases, it is of the utmost importance to develop streamlined approaches to environmental risk assessment in order to prioritize mitigation measures. Whole-cell biosensors or bioreporters and speciation modeling have both become of increasing interest to determine the bioavailability of pollutants, as bioavailability is increasingly in use as an indicator of risk. Herein, we examine whether bioreporter results are able to reflect expectations based on chemical reactivity and speciation modeling, with the hope to extend the research into a wider framework of risk assessment. We study a specific test case concerning the bioavailability of lead (Pb) in aqueous environments containing Pb-complexing ligands. Ligands studied include ethylene diamine tetra-acetic acid (EDTA), meso-2,3 dimercaptosuccinic acid (DMSA), leucine, methionine, cysteine, glutathione, and humic acid (HA), and we also performed experiments using natural water samples from Lake Tai (Taihu), the third largest lake in China. We find that EDTA, DMSA, cysteine, glutathione, and HA amendment significantly reduced Pb bioavailability with increasing ligand concentration according to a log-sigmoid trend. Increasing dissolved organic carbon in Taihu water also had the same effect, whereas leucine and methionine had no notable effect on bioavailability at the concentrations tested. We find that bioreporter results are in accord with the reduction of aqueous Pb 2+ that we expect from the relative complexation affinities of the different ligands tested. For EDTA and HA, for which reasonably accurate ionization and complexation constants are known, speciation modeling is in agreement with bioreporter response to within the level of uncertainty recognised as reasonable by the United States Environmental Protection Agency for speciation-based risk assessment applications. These findings represent a first step toward using bioreporter technology to streamline

  18. The evolving energy budget of accretionary wedges

    Science.gov (United States)

    McBeck, Jessica; Cooke, Michele; Maillot, Bertrand; Souloumiac, Pauline

    2017-04-01

    The energy budget of evolving accretionary systems reveals how deformational processes partition energy as faults slip, topography uplifts, and layer-parallel shortening produces distributed off-fault deformation. The energy budget provides a quantitative framework for evaluating the energetic contribution or consumption of diverse deformation mechanisms. We investigate energy partitioning in evolving accretionary prisms by synthesizing data from physical sand accretion experiments and numerical accretion simulations. We incorporate incremental strain fields and cumulative force measurements from two suites of experiments to design numerical simulations that represent accretionary wedges with stronger and weaker detachment faults. One suite of the physical experiments includes a basal glass bead layer and the other does not. Two physical experiments within each suite implement different boundary conditions (stable base versus moving base configuration). Synthesizing observations from the differing base configurations reduces the influence of sidewall friction because the force vector produced by sidewall friction points in opposite directions depending on whether the base is fixed or moving. With the numerical simulations, we calculate the energy budget at two stages of accretion: at the maximum force preceding the development of the first thrust pair, and at the minimum force following the development of the pair. To identify the appropriate combination of material and fault properties to apply in the simulations, we systematically vary the Young's modulus and the fault static and dynamic friction coefficients in numerical accretion simulations, and identify the set of parameters that minimizes the misfit between the normal force measured on the physical backwall and the numerically simulated force. Following this derivation of the appropriate material and fault properties, we calculate the components of the work budget in the numerical simulations and in the

  19. Key concepts in glioblastoma therapy

    DEFF Research Database (Denmark)

    Bartek, Jiri; Ng, Kimberly; Bartek, Jiri

    2012-01-01

    principles that drive the formulation of therapeutic strategies in glioblastoma. Specifically, the concepts of tumour heterogeneity, oncogene addiction, non-oncogene addiction, tumour initiating cells, tumour microenvironment, non-coding sequences and DNA damage response will be reviewed....

  20. Intrinsic immunogenicity of rapidly-degradable polymers evolves during degradation.

    Science.gov (United States)

    Andorko, James I; Hess, Krystina L; Pineault, Kevin G; Jewell, Christopher M

    2016-03-01

    Recent studies reveal many biomaterial vaccine carriers are able to activate immunostimulatory pathways, even in the absence of other immune signals. How the changing properties of polymers during biodegradation impact this intrinsic immunogenicity is not well studied, yet this information could contribute to rational design of degradable vaccine carriers that help direct immune response. We use degradable poly(beta-amino esters) (PBAEs) to explore intrinsic immunogenicity as a function of the degree of polymer degradation and polymer form (e.g., soluble, particles). PBAE particles condensed by electrostatic interaction to mimic a common vaccine approach strongly activate dendritic cells, drive antigen presentation, and enhance T cell proliferation in the presence of antigen. Polymer molecular weight strongly influences these effects, with maximum stimulation at short degradation times--corresponding to high molecular weight--and waning levels as degradation continues. In contrast, free polymer is immunologically inert. In mice, PBAE particles increase the numbers and activation state of cells in lymph nodes. Mechanistic studies reveal that this evolving immunogenicity occurs as the physicochemical properties and concentration of particles change during polymer degradation. This work confirms the immunological profile of degradable, synthetic polymers can evolve over time and creates an opportunity to leverage this feature in new vaccines. Degradable polymers are increasingly important in vaccination, but how the inherent immunogenicity of polymers changes during degradation is poorly understood. Using common rapidly-degradable vaccine carriers, we show that the activation of immune cells--even in the absence of other adjuvants--depends on polymer form (e.g., free, particulate) and the extent of degradation. These changing characteristics alter the physicochemical properties (e.g., charge, size, molecular weight) of polymer particles, driving changes in

  1. The prehistory of the cytoskeleton concept.

    Science.gov (United States)

    Zampieri, Fabio; Coen, Matteo; Gabbiani, Giulio

    2014-08-01

    Here we discuss how the concept and the name of cytoskeleton were generated and started to evolve over the last two centuries into what is presently a basic topic of modern biology. We also attempt to describe some facets of the emergence of cytoskeleton component characterization in which our laboratory was in part involved. © 2014 Wiley Periodicals, Inc.

  2. Origins of Allostery and Evolvability in Proteins: A Case Study.

    Science.gov (United States)

    Raman, Arjun S; White, K Ian; Ranganathan, Rama

    2016-07-14

    Proteins display the capacity for adaptation to new functions, a property critical for evolvability. But what structural principles underlie the capacity for adaptation? Here, we show that adaptation to a physiologically distinct class of ligand specificity in a PSD95, DLG1, ZO-1 (PDZ) domain preferentially occurs through class-bridging intermediate mutations located distant from the ligand-binding site. These mutations provide a functional link between ligand classes and demonstrate the principle of "conditional neutrality" in mediating evolutionary adaptation. Structures show that class-bridging mutations work allosterically to open up conformational plasticity at the active site, permitting novel functions while retaining existing function. More generally, the class-bridging phenotype arises from mutations in an evolutionarily conserved network of coevolving amino acids in the PDZ family (the sector) that connects the active site to distant surface sites. These findings introduce the concept that allostery in proteins could have its origins not in protein function but in the capacity to adapt. Copyright © 2016 Elsevier Inc. All rights reserved.

  3. Astrophysical Concepts

    CERN Document Server

    Harwit, Martin

    2006-01-01

    This classic text, aimed at senior undergraduates and beginning graduate students in physics and astronomy, presents a wide range of astrophysical concepts in sufficient depth to give the reader a quantitative understanding of the subject. Emphasizing physical concepts, the book outlines cosmic events but does not portray them in detail: it provides a series of astrophysical sketches. For this fourth edition, nearly every part of the text has been reconsidered and rewritten, new sections have been added to cover recent developments, and others have been extensively revised and brought up to date. The book begins with an outline of the scope of modern astrophysics and enumerates some of the outstanding problems faced in the field today. The basic physics needed to tackle these questions are developed in the next few chapters using specific astronomical processes as examples. The second half of the book enlarges on these topics and shows how we can obtain quantitative insight into the structure and evolution of...

  4. On the Critical Role of Divergent Selection in Evolvability

    Directory of Open Access Journals (Sweden)

    Joel Lehman

    2016-08-01

    Full Text Available An ambitious goal in evolutionary robotics is to evolve increasingly complex robotic behaviors with minimal human design effort. Reaching this goal requires evolutionary algorithms that can unlock from genetic encodings their latent potential for evolvability. One issue clouding this goal is conceptual confusion about evolvability, which often obscures the aspects of evolvability that are important or desirable. The danger from such confusion is that it may establish unrealistic goals for evolvability that prove unproductive in practice. An important issue separate from conceptual confusion is the common misalignment between selection and evolvability in evolutionary robotics. While more expressive encodings can represent higher-level adaptations (e.g. sexual reproduction or developmental systems that increase long-term evolutionary potential (i.e. evolvability, realizing such potential requires gradients of fitness and evolvability to align. In other words, selection is often a critical factor limiting increasing evolvability. Thus, drawing from a series of recent papers, this article seeks to both (1 clarify and focus the ways in which the term evolvability is used within artificial evolution, and (2 argue for the importance of one type of selection, i.e. divergent selection, for enabling evolvability. The main argument is that there is a fundamental connection between divergent selection and evolvability (on both the individual and population level that does not hold for typical goal-oriented selection. The conclusion is that selection pressure plays a critical role in realizing the potential for evolvability, and that divergent selection in particular provides a principled mechanism for encouraging evolvability in artificial evolution.

  5. Approximating centrality in evolving graphs: toward sublinearity

    Science.gov (United States)

    Priest, Benjamin W.; Cybenko, George

    2017-05-01

    The identification of important nodes is a ubiquitous problem in the analysis of social networks. Centrality indices (such as degree centrality, closeness centrality, betweenness centrality, PageRank, and others) are used across many domains to accomplish this task. However, the computation of such indices is expensive on large graphs. Moreover, evolving graphs are becoming increasingly important in many applications. It is therefore desirable to develop on-line algorithms that can approximate centrality measures using memory sublinear in the size of the graph. We discuss the challenges facing the semi-streaming computation of many centrality indices. In particular, we apply recent advances in the streaming and sketching literature to provide a preliminary streaming approximation algorithm for degree centrality utilizing CountSketch and a multi-pass semi-streaming approximation algorithm for closeness centrality leveraging a spanner obtained through iteratively sketching the vertex-edge adjacency matrix. We also discuss possible ways forward for approximating betweenness centrality, as well as spectral measures of centrality. We provide a preliminary result using sketched low-rank approximations to approximate the output of the HITS algorithm.

  6. Functional Topology of Evolving Urban Drainage Networks

    Science.gov (United States)

    Yang, Soohyun; Paik, Kyungrock; McGrath, Gavan S.; Urich, Christian; Krueger, Elisabeth; Kumar, Praveen; Rao, P. Suresh C.

    2017-11-01

    We investigated the scaling and topology of engineered urban drainage networks (UDNs) in two cities, and further examined UDN evolution over decades. UDN scaling was analyzed using two power law scaling characteristics widely employed for river networks: (1) Hack's law of length (L)-area (A) [L∝Ah] and (2) exceedance probability distribution of upstream contributing area (δ) [P>(A≥δ>)˜aδ-ɛ]. For the smallest UDNs ((A≥δ>) plots for river networks are abruptly truncated, those for UDNs display exponential tempering [P>(A≥δ>)=aδ-ɛexp⁡>(-cδ>)]. The tempering parameter c decreases as the UDNs grow, implying that the distribution evolves in time to resemble those for river networks. However, the power law exponent ɛ for large UDNs tends to be greater than the range reported for river networks. Differences in generative processes and engineering design constraints contribute to observed differences in the evolution of UDNs and river networks, including subnet heterogeneity and nonrandom branching.

  7. An Evolving Worldview: Making Open Source Easy

    Science.gov (United States)

    Rice, Z.

    2017-12-01

    NASA Worldview is an interactive interface for browsing full-resolution, global satellite imagery. Worldview supports an open data policy so that academia, private industries and the general public can use NASA's satellite data to address Earth science related issues. Worldview was open sourced in 2014. By shifting to an open source approach, the Worldview application has evolved to better serve end-users. Project developers are able to have discussions with end-users and community developers to understand issues and develop new features. Community developers are able to track upcoming features, collaborate on them and make their own contributions. Developers who discover issues are able to address those issues and submit a fix. This reduces the time it takes for a project developer to reproduce an issue or develop a new feature. Getting new developers to contribute to the project has been one of the most important and difficult aspects of open sourcing Worldview. After witnessing potential outside contributors struggle, a focus has been made on making the installation of Worldview simple to reduce the initial learning curve and make contributing code easy. One way we have addressed this is through a simplified setup process. Our setup documentation includes a set of prerequisites and a set of straightforward commands to clone, configure, install and run. This presentation will emphasize our focus to simplify and standardize Worldview's open source code so that more people are able to contribute. The more people who contribute, the better the application will become over time.

  8. Extreme insular dwarfism evolved in a mammoth.

    Science.gov (United States)

    Herridge, Victoria L; Lister, Adrian M

    2012-08-22

    The insular dwarfism seen in Pleistocene elephants has come to epitomize the island rule; yet our understanding of this phenomenon is hampered by poor taxonomy. For Mediterranean dwarf elephants, where the most extreme cases of insular dwarfism are observed, a key systematic question remains unresolved: are all taxa phyletic dwarfs of a single mainland species Palaeoloxodon antiquus (straight-tusked elephant), or are some referable to Mammuthus (mammoths)? Ancient DNA and geochronological evidence have been used to support a Mammuthus origin for the Cretan 'Palaeoloxodon' creticus, but these studies have been shown to be flawed. On the basis of existing collections and recent field discoveries, we present new, morphological evidence for the taxonomic status of 'P'. creticus, and show that it is indeed a mammoth, most probably derived from Early Pleistocene Mammuthus meridionalis or possibly Late Pliocene Mammuthus rumanus. We also show that Mammuthus creticus is smaller than other known insular dwarf mammoths, and is similar in size to the smallest dwarf Palaeoloxodon species from Sicily and Malta, making it the smallest mammoth species known to have existed. These findings indicate that extreme insular dwarfism has evolved to a similar degree independently in two elephant lineages.

  9. How does cognition evolve? Phylogenetic comparative psychology.

    Science.gov (United States)

    MacLean, Evan L; Matthews, Luke J; Hare, Brian A; Nunn, Charles L; Anderson, Rindy C; Aureli, Filippo; Brannon, Elizabeth M; Call, Josep; Drea, Christine M; Emery, Nathan J; Haun, Daniel B M; Herrmann, Esther; Jacobs, Lucia F; Platt, Michael L; Rosati, Alexandra G; Sandel, Aaron A; Schroepfer, Kara K; Seed, Amanda M; Tan, Jingzhi; van Schaik, Carel P; Wobber, Victoria

    2012-03-01

    Now more than ever animal studies have the potential to test hypotheses regarding how cognition evolves. Comparative psychologists have developed new techniques to probe the cognitive mechanisms underlying animal behavior, and they have become increasingly skillful at adapting methodologies to test multiple species. Meanwhile, evolutionary biologists have generated quantitative approaches to investigate the phylogenetic distribution and function of phenotypic traits, including cognition. In particular, phylogenetic methods can quantitatively (1) test whether specific cognitive abilities are correlated with life history (e.g., lifespan), morphology (e.g., brain size), or socio-ecological variables (e.g., social system), (2) measure how strongly phylogenetic relatedness predicts the distribution of cognitive skills across species, and (3) estimate the ancestral state of a given cognitive trait using measures of cognitive performance from extant species. Phylogenetic methods can also be used to guide the selection of species comparisons that offer the strongest tests of a priori predictions of cognitive evolutionary hypotheses (i.e., phylogenetic targeting). Here, we explain how an integration of comparative psychology and evolutionary biology will answer a host of questions regarding the phylogenetic distribution and history of cognitive traits, as well as the evolutionary processes that drove their evolution.

  10. An evolving network model with modular growth

    International Nuclear Information System (INIS)

    Zou Zhi-Yun; Liu Peng; Lei Li; Gao Jian-Zhi

    2012-01-01

    In this paper, we propose an evolving network model growing fast in units of module, according to the analysis of the evolution characteristics in real complex networks. Each module is a small-world network containing several interconnected nodes and the nodes between the modules are linked by preferential attachment on degree of nodes. We study the modularity measure of the proposed model, which can be adjusted by changing the ratio of the number of inner-module edges and the number of inter-module edges. In view of the mean-field theory, we develop an analytical function of the degree distribution, which is verified by a numerical example and indicates that the degree distribution shows characteristics of the small-world network and the scale-free network distinctly at different segments. The clustering coefficient and the average path length of the network are simulated numerically, indicating that the network shows the small-world property and is affected little by the randomness of the new module. (interdisciplinary physics and related areas of science and technology)

  11. How does cognition evolve? Phylogenetic comparative psychology

    Science.gov (United States)

    Matthews, Luke J.; Hare, Brian A.; Nunn, Charles L.; Anderson, Rindy C.; Aureli, Filippo; Brannon, Elizabeth M.; Call, Josep; Drea, Christine M.; Emery, Nathan J.; Haun, Daniel B. M.; Herrmann, Esther; Jacobs, Lucia F.; Platt, Michael L.; Rosati, Alexandra G.; Sandel, Aaron A.; Schroepfer, Kara K.; Seed, Amanda M.; Tan, Jingzhi; van Schaik, Carel P.; Wobber, Victoria

    2014-01-01

    Now more than ever animal studies have the potential to test hypotheses regarding how cognition evolves. Comparative psychologists have developed new techniques to probe the cognitive mechanisms underlying animal behavior, and they have become increasingly skillful at adapting methodologies to test multiple species. Meanwhile, evolutionary biologists have generated quantitative approaches to investigate the phylogenetic distribution and function of phenotypic traits, including cognition. In particular, phylogenetic methods can quantitatively (1) test whether specific cognitive abilities are correlated with life history (e.g., lifespan), morphology (e.g., brain size), or socio-ecological variables (e.g., social system), (2) measure how strongly phylogenetic relatedness predicts the distribution of cognitive skills across species, and (3) estimate the ancestral state of a given cognitive trait using measures of cognitive performance from extant species. Phylogenetic methods can also be used to guide the selection of species comparisons that offer the strongest tests of a priori predictions of cognitive evolutionary hypotheses (i.e., phylogenetic targeting). Here, we explain how an integration of comparative psychology and evolutionary biology will answer a host of questions regarding the phylogenetic distribution and history of cognitive traits, as well as the evolutionary processes that drove their evolution. PMID:21927850

  12. A local-world evolving hypernetwork model

    International Nuclear Information System (INIS)

    Yang Guang-Yong; Liu Jian-Guo

    2014-01-01

    Complex hypernetworks are ubiquitous in the real system. It is very important to investigate the evolution mechanisms. In this paper, we present a local-world evolving hypernetwork model by taking into account the hyperedge growth and local-world hyperedge preferential attachment mechanisms. At each time step, a newly added hyperedge encircles a new coming node and a number of nodes from a randomly selected local world. The number of the selected nodes from the local world obeys the uniform distribution and its mean value is m. The analytical and simulation results show that the hyperdegree approximately obeys the power-law form and the exponent of hyperdegree distribution is γ = 2 + 1/m. Furthermore, we numerically investigate the node degree, hyperedge degree, clustering coefficient, as well as the average distance, and find that the hypernetwork model shares the scale-free and small-world properties, which shed some light for deeply understanding the evolution mechanism of the real systems. (interdisciplinary physics and related areas of science and technology)

  13. Evolving autonomous learning in cognitive networks.

    Science.gov (United States)

    Sheneman, Leigh; Hintze, Arend

    2017-12-01

    There are two common approaches for optimizing the performance of a machine: genetic algorithms and machine learning. A genetic algorithm is applied over many generations whereas machine learning works by applying feedback until the system meets a performance threshold. These methods have been previously combined, particularly in artificial neural networks using an external objective feedback mechanism. We adapt this approach to Markov Brains, which are evolvable networks of probabilistic and deterministic logic gates. Prior to this work MB could only adapt from one generation to the other, so we introduce feedback gates which augment their ability to learn during their lifetime. We show that Markov Brains can incorporate these feedback gates in such a way that they do not rely on an external objective feedback signal, but instead can generate internal feedback that is then used to learn. This results in a more biologically accurate model of the evolution of learning, which will enable us to study the interplay between evolution and learning and could be another step towards autonomously learning machines.

  14. Orbital Decay in Binaries with Evolved Stars

    Science.gov (United States)

    Sun, Meng; Arras, Phil; Weinberg, Nevin N.; Troup, Nicholas; Majewski, Steven R.

    2018-01-01

    Two mechanisms are often invoked to explain tidal friction in binary systems. The ``dynamical tide” is the resonant excitation of internal gravity waves by the tide, and their subsequent damping by nonlinear fluid processes or thermal diffusion. The ``equilibrium tide” refers to non-resonant excitation of fluid motion in the star’s convection zone, with damping by interaction with the turbulent eddies. There have been numerous studies of these processes in main sequence stars, but less so on the subgiant and red giant branches. Motivated by the newly discovered close binary systems in the Apache Point Observatory Galactic Evolution Experiment (APOGEE-1), we have performed calculations of both the dynamical and equilibrium tide processes for stars over a range of mass as the star’s cease core hydrogen burning and evolve to shell burning. Even for stars which had a radiative core on the main sequence, the dynamical tide may have very large amplitude in the newly radiative core in post-main sequence, giving rise to wave breaking. The resulting large dynamical tide dissipation rate is compared to the equilibrium tide, and the range of secondary masses and orbital periods over which rapid orbital decay may occur will be discussed, as well as applications to close APOGEE binaries.

  15. Minority games, evolving capitals and replicator dynamics

    International Nuclear Information System (INIS)

    Galla, Tobias; Zhang, Yi-Cheng

    2009-01-01

    We discuss a simple version of the minority game (MG) in which agents hold only one strategy each, but in which their capitals evolve dynamically according to their success and in which the total trading volume varies in time accordingly. This feature is known to be crucial for MGs to reproduce stylized facts of real market data. The stationary states and phase diagram of the model can be computed, and we show that the ergodicity breaking phase transition common for MGs, and marked by a divergence of the integrated response, is present also in this simplified model. An analogous majority game turns out to be relatively void of interesting features, and the total capital is found to diverge in time. Introducing a restraining force leads to a model akin to the replicator dynamics of evolutionary game theory, and we demonstrate that here a different type of phase transition is observed. Finally we briefly discuss the relation of this model with one strategy per player to more sophisticated minority games with dynamical capitals and several trading strategies per agent

  16. An evolving model of online bipartite networks

    Science.gov (United States)

    Zhang, Chu-Xu; Zhang, Zi-Ke; Liu, Chuang

    2013-12-01

    Understanding the structure and evolution of online bipartite networks is a significant task since they play a crucial role in various e-commerce services nowadays. Recently, various attempts have been tried to propose different models, resulting in either power-law or exponential degree distributions. However, many empirical results show that the user degree distribution actually follows a shifted power-law distribution, the so-called Mandelbrot’s law, which cannot be fully described by previous models. In this paper, we propose an evolving model, considering two different user behaviors: random and preferential attachment. Extensive empirical results on two real bipartite networks, Delicious and CiteULike, show that the theoretical model can well characterize the structure of real networks for both user and object degree distributions. In addition, we introduce a structural parameter p, to demonstrate that the hybrid user behavior leads to the shifted power-law degree distribution, and the region of power-law tail will increase with the increment of p. The proposed model might shed some lights in understanding the underlying laws governing the structure of real online bipartite networks.

  17. Evolving application of biomimetic nanostructured hydroxyapatite

    Directory of Open Access Journals (Sweden)

    Norberto Roveri

    2010-11-01

    Full Text Available Norberto Roveri, Michele IafiscoLaboratory of Environmental and Biological Structural Chemistry (LEBSC, Dipartimento di Chimica ‘G. Ciamician’, Alma Mater Studiorum, Università di Bologna, Bologna, ItalyAbstract: By mimicking Nature, we can design and synthesize inorganic smart materials that are reactive to biological tissues. These smart materials can be utilized to design innovative third-generation biomaterials, which are able to not only optimize their interaction with biological tissues and environment, but also mimic biogenic materials in their functionalities. The biomedical applications involve increasing the biomimetic levels from chemical composition, structural organization, morphology, mechanical behavior, nanostructure, and bulk and surface chemical–physical properties until the surface becomes bioreactive and stimulates cellular materials. The chemical–physical characteristics of biogenic hydroxyapatites from bone and tooth have been described, in order to point out the elective sides, which are important to reproduce the design of a new biomimetic synthetic hydroxyapatite. This review outlines the evolving applications of biomimetic synthetic calcium phosphates, details the main characteristics of bone and tooth, where the calcium phosphates are present, and discusses the chemical–physical characteristics of biomimetic calcium phosphates, methods of synthesizing them, and some of their biomedical applications.Keywords: hydroxyapatite, nanocrystals, biomimetism, biomaterials, drug delivery, remineralization

  18. Introductory concepts

    International Nuclear Information System (INIS)

    Barnes, W.E.

    1983-01-01

    Physical theories are commonly classified as being either ''classical'' or ''modern''. The reasons for this distinction are both historical and substantive. Limited in the sophistication of their measuring instruments, early scientists proposed theories appropriate for the description of the simplest and most accessible physical phenomena, e.g., the trajectories of the planets. Because of the class of phenomena observed, certain beliefs came to underlie all classical theories with regard to the nature of time, space, matter, etc. For example, the idea was undisputed that an object has at all times both a definite position and velocity. Not until the interior of the atom and the nature of electromagnetic radiation were explored was it discovered that the concepts of classical physics are inadequate to deal with many phenomena. A reassessment of fundamental postulates led to the formulation of modern physics which, it is believed, successfully treats the behavior of all physical systems. To gain an understanding of the rudiments of modern physics, one proceeds as the early scientists did by first mastering the classical concepts that emerge from their intuitive picture of the world. Modifications of these concepts are subsequently introduced which allow a more accurate treatment of physical phenomena, particularly atomic and nuclear systems

  19. Modeling and Understanding Time-Evolving Scenarios

    Directory of Open Access Journals (Sweden)

    Riccardo Melen

    2015-08-01

    Full Text Available In this paper, we consider the problem of modeling application scenarios characterized by variability over time and involving heterogeneous kinds of knowledge. The evolution of distributed technologies creates new and challenging possibilities of integrating different kinds of problem solving methods, obtaining many benefits from the user point of view. In particular, we propose here a multilayer modeling system and adopt the Knowledge Artifact concept to tie together statistical and Artificial Intelligence rule-based methods to tackle problems in ubiquitous and distributed scenarios.

  20. Stem Cell Therapy in Wound Healing and Tissue Regeneration

    Directory of Open Access Journals (Sweden)

    Anna Meiliana

    2016-08-01

    a novel approach to many diseases. SUMMARY: Wound healing therapies continue to rapidly evolve, with advances in basic science and engineering research heralding the development of new therapies, as well as ways to modify existing treatments. Stem cell-based therapy is one of the most promising therapeutic concepts for wound healing. Advances in stem cell biology have enabled researchers and clinicians alike with access to cells capable of actively modulating the healing response.  KEYWORDS: wound healing, tissue regeneration, stem cells therapy

  1. Comparison of in vitro test systems using bacterial and mammalian cells for genotoxicity assessment within the "health-related indication value (HRIV) concept.

    Science.gov (United States)

    Prantl, Eva-Maria; Kramer, Meike; Schmidt, Carsten K; Knauer, Martina; Gartiser, Stefan; Shuliakevich, Aliaksandra; Milas, Julia; Glatt, Hansruedi; Meinl, Walter; Hollert, Henner

    2018-02-01

    In numerous cases, the German health-related indication value (HRIV) concept has proved its practicability for the assessment of drinking water relevant trace substances (Umweltbundesamt 2003). The HRIV is based on the toxicological profile of a substance. An open point of the HRIV concept has been the assignment of standardized test procedures to be used for the assessment. The level of the HRIV is at its lowest as soon as the genotoxicity of the substance is detected. As a single test on its own, it is not sufficient enough to assess the human toxicological relevance of a genotoxic effect or exclude it in the case of a negative result; a reasonable test battery was required, technically oriented towards the already harmonized international, hierarchical evaluation for toxicological assessment of chemicals. Therefore, an important aim of this project was to define a strategy for the genotoxicological assessment of anthropogenic trace substances. The basic test battery for genotoxicity of micropollutants in drinking water needs to fulfill several requirements. Although quick test results are needed for the determination of HRIV, a high degree of transferability to human genotoxicity should be ensured. Therefore, an in vitro genotoxicity test battery consisting of the Ames fluctuation test with two tester strains (ISO 11350), the umu test and the micronucleus test, or from the Ames test with five tester strains (OECD 471) and the micronucleus test is proposed. On the basis of selected test substances, it could be shown that the test battery leads to positive, indifferent, and negative results. Given indifferent results, the health authority and the water supplier must assume that it is a genotoxic substance. Genetically modified tester strains are being sensitive to different chemical classes by expression of selected mammalian key enzymes for example nitroreductase, acetyltransferase, and glutathione-S-transferase. These strains may provide valuable additional

  2. The Co-evolution of Concepts and Motivation.

    Science.gov (United States)

    Delton, Andrew W; Sell, Aaron

    2014-04-01

    Does the human mind contain evolved concepts? Many psychologists have doubted this or have investigated only a narrow set (e.g., object, number, cause). Does the human mind contain evolved motivational systems? Many more assent to this claim, holding that there are evolved motivational systems for, among other tasks, social affiliation, aggressive competition, and finding food. An emerging research program, however, reveals that these are not separate questions. Any evolved motivational system needs a wealth of conceptual structure that tethers the motivations to real world entities. For instance, what use is a fear of predators without knowing what predators are and how to respond to them effectively? As we illustrate with case studies of cooperation and conflict, there is no motivation without representation: To generate adaptive behavior, motivational systems must be interwoven with the concepts required to support them, and cannot be understood without explicit reference to those concepts.

  3. Evolving water science in the Anthropocene

    Science.gov (United States)

    Savenije, H. H. G.; Hoekstra, A. Y.; van der Zaag, P.

    2013-06-01

    This paper reviews the changing relation between man and water since the industrial revolution, the period that has been called the Anthropocene because of the unprecedented scale at which humans have altered the planet. We show how the rapidly changing reality urges us to continuously improve our understanding of the complex interactions between man and the water system. The paper starts with demonstrating that hydrology and the science of water resources management have played key roles in human and economic development throughout history; yet these roles have often been marginalised or obscured. Knowledge on hydrology and water resources engineering and management helped to transform the landscape, and thus also the very hydrology within catchments itself. It is only fairly recent that water experts have become self-conscious of such mechanisms, exemplified by several concepts that try to internalise them (integrated water resources management, eco-hydrology, socio-hydrology). We have reached a stage where a more systemic understanding of scale interdependencies can inform the sustainable governance of water systems, using new concepts like precipitationsheds, virtual water transfers, water footprint and water value flow.

  4. Public participation at Fernald: FERMCO's evolving role

    International Nuclear Information System (INIS)

    Williams, J.B.; Fellman, R.W.; Brettschneider, D.J.

    1995-01-01

    In an effort to improve public involvement in the site restoration decision making process, the DOE has established site specific advisory boards, of which the Fernald Citizens Task Force is one. The Fernald Task Force is focused on making recommendations in four areas: (1) What should be the future use of the site? (2) Determinations of cleanup levels (how clean is clean?) (3) Where should the wastes be disposed of? (4) What should be the cleanup priorities? Because these questions are being asked very early in the decision-making process, the answers are necessarily qualified, and are based on a combination of preliminary data, assumptions, and professional judgment. The requirement to make progress in the absence of accurate data has necessitated FERMCO and the Task Force to employ an approach similar to sensitivity analysis, in which a range of possible data values are evaluated and the relative importance of the various factors is assessed. Because of its charter to provide recommendations of future site use, the Task Force has developed a sitewide perspective, compared to the more common operable unit specific focus of public participation under CERCLA. The relationship between FERMCO and the Task Force is evolving toward one of partnership with DOE in managing the obstacles and hidden opportunities for success. The Task Force likely will continue to participate in the Fernald project long after its initial recommendations have been made. DOE already has made the commitment that the process of public participation will extend into the Remedial Design phase. There is substantial reason for optimism that continuing the Task Force process through the design phase will assist in developing the appropriate balance of cost and engineered protectiveness

  5. Patient-Derived Xenografts of Non Small Cell Lung Cancer: Resurgence of an Old Model for Investigation of Modern Concepts of Tailored Therapy and Cancer Stem Cells

    Directory of Open Access Journals (Sweden)

    Massimo Moro

    2012-01-01

    Full Text Available Current chemotherapy regimens have unsatisfactory results in most advanced solid tumors. It is therefore imperative to devise novel therapeutic strategies and to optimize selection of patients, identifying early those who could benefit from available treatments. Mouse models are the most valuable tool for preclinical evaluation of novel therapeutic strategies in cancer and, among them, patient-derived xenografts models (PDX have made a recent comeback in popularity. These models, obtained by direct implants of tissue fragments in immunocompromised mice, have great potential in drug development studies because they faithfully reproduce the patient’s original tumor for both immunohistochemical markers and genetic alterations as well as in terms of response to common therapeutics They also maintain the original tumor heterogeneity, allowing studies of specific cellular subpopulations, including their modulation after drug treatment. Moreover PDXs maintain at least some aspects of the human microenvironment for weeks with the complete substitution with murine stroma occurring only after 2-3 passages in mouse and represent therefore a promising model for studies of tumor-microenvironment interaction. This review summarizes our present knowledge on mouse preclinical cancer models, with a particular attention on patient-derived xenografts of non small cell lung cancer and their relevance for preclinical and biological studies.

  6. Complement and the control of HIV infection: an evolving story.

    Science.gov (United States)

    Frank, Michael M; Hester, Christopher; Jiang, Haixiang

    2014-05-01

    Thirty years ago, investigators isolated and later determined the structure of HIV-1 and its envelope proteins. Using techniques that were effective with other viruses, they prepared vaccines designed to generate antibody or T-cell responses, but they were ineffective in clinical trials. In this article, we consider the role of complement in host defense against enveloped viruses, the role it might play in the antibody response and why complement has not controlled HIV-1 infection. Complement consists of a large group of cell-bound and plasma proteins that are an integral part of the innate immune system. They provide a first line of defense against microbes and also play a role in the immune response. Here we review the studies of complement-mediated HIV destruction and the role of complement in the HIV antibody response. HIV-1 has evolved a complex defense to prevent complement-mediated killing reviewed here. As part of these studies, we have discovered that HIV-1 envelope, on administration into animals, is rapidly broken down into small peptides that may prove to be very inefficient at provident the type of antigenic stimulation that leads to an effective immune response. Improving complement binding and stabilizing envelope may improve the vaccine response.

  7. "Give us this day our daily bread"--evolving concepts in celiac sprue.

    Science.gov (United States)

    Upton, Melissa P

    2008-10-01

    Celiac sprue affects genetically susceptible individuals, who develop small intestinal injury and malabsorption following dietary exposure to gluten. The histologic features are nonspecific but characteristic. To outline the histologic features of celiac sprue and the necessary clinical context to permit a diagnosis of celiac sprue, to assist the pathologist to identify artifactual biopsy changes that may mimic sprue, to define the differential diagnosis for conditions with a similar histology, and to review historic investigations of this disease. Sources include the historic experiments and clinical work of members of the Gastroenterology Division of the Department of Medicine and experiences with gastrointestinal pathology consultation material at the University of Washington, Seattle, with reference to selected peer-reviewed articles. Confirmation of a diagnosis of celiac sprue is 2-fold: first, biopsy evidence of a characteristic, but nonspecific, pattern of injury including villous blunting or flattening, surface enterocyte damage, and increased intraepithelial lymphocytes; and second, dramatic clinical response to a gluten-free diet. Complete gluten removal from the diet is effective treatment for patients with symptoms of malabsorption; however, lifelong adherence to the diet is expensive, socially limiting, and nearly impossible on a contemporary diet with manufactured foodstuffs. Therefore, pathologists should avoid overdiagnosis of celiac disease based on minimal, nonspecific histologic changes.

  8. Evolving Concepts of Reflux: The Ups and Downs of the LES

    Directory of Open Access Journals (Sweden)

    Tom R DeMeester

    2002-01-01

    Full Text Available The common denominator for virtually all episodes of gastroesophageal reflux in health and disease is the loss of the barrier that confines the gastric environment to the stomach. Factors important in the function of the barrier are its pressure, length and position. In early reflux disease, overeating, gastric distention, delayed emptying and aerophagia lead to transient losses of the barrier. A permanent loss results from inflammatory injury to the muscle of the barrier with free flow of gastric juice into the esophageal body and its subsequent injury. Corrective therapy requires augmentation or restoration of barrier function.

  9. Adrenocortical neoplasia: Evolving concepts in tumorigenesis with an emphasis on adrenal cortical carcinoma variants

    NARCIS (Netherlands)

    R.R. de Krijger (Ronald); T.G. Papathomas (Thomas)

    2012-01-01

    textabstractAdrenocortical carcinoma (ACC) is a rare, heterogeneous malignancy with a poor prognosis. According to WHO classification 2004, ACC variants include oncocytic ACCs, myxoid ACCs and ACCs with sarcomatous areas. Herein, we provide a comprehensive review of these rare subtypes of

  10. Developing Culturally Responsive Mathematics Teachers: Secondary Teachers' Evolving Conceptions of Knowing Students

    Science.gov (United States)

    Parker, Frieda; Bartell, Tonya Gau; Novak, Jodie D.

    2017-01-01

    Research advances in teaching, learning, curriculum, and assessment have not changed the continued underperformance of marginalized students in mathematics education. Culturally responsive teaching is a means of addressing the needs of these students. It is sometimes challenging, however, to convince secondary mathematics teachers about the…

  11. Breast cancer and breast health awareness as an evolving health promotion concept

    International Nuclear Information System (INIS)

    Plesnicar, A.; Kralj, B.; Kovac, V.

    2004-01-01

    Background. Breast cancer is the most frequent malignant disease in the majority of developed countries. In the last few years the introduction of mammography screening programmes has resulted in an improved survival of breast cancer patients. However, the incidence of the disease in these countries is still on the increase. Present focus on secondary breast cancer prevention activities, consisting of early detection and treatment, cannot ensure a decrease of breast cancer incidence. Improved breast health awareness could therefore represent a part of specific health promotion activities aimed at decreasing the incidence of breast cancer. Conclusions. In developed countries breast cancer is a significant health care issue. Secondary breast cancer prevention activities should therefore be complemented by specific health promotion activities in order to reduce its incidence in the future. Primary breast cancer prevention would include health promotion activities aimed at enhancement of the individual as well as collective breast health awareness. Properly enlightened members of the influential population groups could attain appropriate changes in the fields of legislation, taxation, customs and commercial regulations that would enable women to control their own breast health. (author)

  12. Extended regimen combined oral contraception: A review of evolving concepts and acceptance by women and clinicians.

    Science.gov (United States)

    Nappi, Rossella E; Kaunitz, Andrew M; Bitzer, Johannes

    2016-01-01

    The clinical utility of extended regimen combined oral contraceptives (COCs) is increasingly being recognised. Our objective was to understand the attitudes of women and clinicians about the use of these regimens. We present the rationale for extended regimen COCs from a historical perspective, and trace their evolution and growing popularity in light of their clinical benefits. We conclude by offering potential strategies for counselling women about extended regimen COC options. We conducted a MEDLINE search to identify and summarise studies of extended regimen COCs, focusing on attitudes of women and clinicians regarding efficacy, safety/tolerability and fewer scheduled bleeding episodes and other potential benefits. The body of contemporary literature on extended regimen COCs suggests that their contraceptive efficacy is comparable to that of conventional 28-day (i.e., 21/7) regimens. For women seeking contraception that allows infrequent scheduled bleeding episodes, particularly those who suffer from hormone withdrawal symptoms and cyclical symptoms (e.g., headache, mood changes, dysmenorrhoea, heavy menstrual bleeding), extended regimen COCs are an effective and safe option. Although satisfaction with extended regimen COCs in clinical trials is high, misperceptions about continuous hormone use may still limit the widespread acceptance of this approach. Despite the widespread acceptance among clinicians of extended regimen COCs as an effective and safe contraceptive option, these regimens are underused, likely due to a lack of awareness about their availability and utility among women. Improved patient education and counselling regarding the safety and benefits of extended regimen COCs may help women make more informed contraceptive choices.

  13. An Evolving Joint Space Campaign Concept and the Army’s Role

    Science.gov (United States)

    1992-05-29

    drive to conceptually extend the air environment out to include space by assuming "aerospace" as an encompassing, seamiass enviion- ment. Nonetheless...adaptions or additions will be presented. I believe that more than enough of Corbett’s framwork wLl reMain intact so that his theory retains its utility., War

  14. Refractory angina pectoris in end-stage coronary artery disease : Evolving therapeutic concepts

    NARCIS (Netherlands)

    Schoebel, FC; Frazier, OH; Jessurun, GAJ; DeJongste, MJL; Kadipasaoglu, KA; Jax, TW; Heintzen, MP; Cooley, DA; Strauer, BE; Leschke, M

    1997-01-01

    Refractory angina pectoris in coronary artery disease is defined as the persistence of severe anginal symptoms despite maximal conventional antianginal combination therapy. Further, the option to use an invasive revascularization procedure such as percutaneous coronary balloon angioplasty or

  15. Anti-EGFR-Targeted Therapy for Esophageal and Gastric Cancers: An Evolving Concept

    Directory of Open Access Journals (Sweden)

    Tomislav Dragovich

    2009-01-01

    Full Text Available Cancers of the esophagus and stomach present a major health burden worldwide. In the past 30 years we have witnessed some interesting shifts in terms of epidemiology of esophago gastric cancers. Regardless of a world region, the majority of patients diagnosed with esophageal or gastric cancers die from progression or recurrence of their disease. While there are many active cytotoxic agents for esophageal and stomach cancers, their impact on the disease course has been modest at best. Median survival for patients with advanced gastroesophageal cancer is still less than a year. Therefore, novel strategies, based on our understanding of biology and genetics, are desperately needed. Epidermal growth factor receptor (EGFR pathway has been implicated in pathophysiology of many epithelial malignancies, including esophageal and stomach cancers. EGFR inhibitors, small molecule tyrosine kinase inhibitors and monoclonal antibodies, have been explored in patients with esophageal and gastric cancers. It appears that tumors of the distal esophagus and gastroesophageal junction (GEJ may be more sensitive to EGFR blockade than distal gastric adenocarcinomas. Investigations looking into potential molecular predictors of sensitivity to EGFR inhibitors for patients with esophageal and GEJ cancers are ongoing. While we are still searching for those predictors, it is clear that they will be different from ones identified in lung and colorectal cancers. Further development of EGFR inhibitors for esophageal and GEJ cancers should be driven by better understanding of EGFR pathway disregulation that drives cancer progression in a sensitive patient population.

  16. Deep remission: a new concept?

    Science.gov (United States)

    Colombel, Jean-Frédéric; Louis, Edouard; Peyrin-Biroulet, Laurent; Sandborn, William J; Panaccione, Remo

    2012-01-01

    Crohn's disease (CD) is a chronic inflammatory disorder characterized by periods of clinical remission alternating with periods of relapse defined by recurrent clinical symptoms. Persistent inflammation is believed to lead to progressive bowel damage over time, which manifests with the development of strictures, fistulae and abscesses. These disease complications frequently lead to a need for surgical resection, which in turn leads to disability. So CD can be characterized as a chronic, progressive, destructive and disabling disease. In rheumatoid arthritis, treatment paradigms have evolved beyond partial symptom control alone toward the induction and maintenance of sustained biological remission, also known as a 'treat to target' strategy, with the goal of improving long-term disease outcomes. In CD, there is currently no accepted, well-defined, comprehensive treatment goal that entails the treatment of both clinical symptoms and biologic inflammation. It is important that such a treatment concept begins to evolve for CD. A treatment strategy that delays or halts the progression of CD to increasing damage and disability is a priority. As a starting point, a working definition of sustained deep remission (that includes long-term biological remission and symptom control) with defined patient outcomes (including no disease progression) has been proposed. The concept of sustained deep remission represents a goal for CD management that may still evolve. It is not clear if the concept also applies to ulcerative colitis. Clinical trials are needed to evaluate whether treatment algorithms that tailor therapy to achieve deep remission in patients with CD can prevent disease progression and disability. Copyright © 2012 S. Karger AG, Basel.

  17. Diabetes benefit management: evolving strategies for payers.

    Science.gov (United States)

    Tzeel, Albert L

    2011-11-01

    Over the next quarter century, the burden of type 2 diabetes mellitus (T2DM) is expected to at least double. Currently, 1 in every 10 healthcare dollars is spent on diabetes management; by 2050, it has been projected that the annual costs of managing T2DM will rise to $336 billion. Without substantial, systemic changes, T2DM management costs will lead to a potentially untenable strain on the healthcare system. However, the appropriate management of diabetes can reduce associated mortality and delay comorbidities. In addition, adequate glycemic control can improve patient outcomes and significantly reduce diabetes-related complications. This article provides an overview of key concepts associated with a value-based insurance design (VBID) approach to T2DM coverage. By promoting the use of services or treatments that provide high benefits relative to cost, and by alternatively discouraging patients from utilizing services whose benefits do not justify their cost, VBID improves the quality of healthcare while simultaneously reining in spending. VBID initiatives tend to focus on chronic disease management and generally target prescription drug use. However, some programs have expanded their scope by incorporating services traditionally offered by wellness and disease management programs. The concept of VBID is growing, and it is increasingly being implemented by a diverse and growing number of public and private entities, including pharmacy benefit managers, health plans, and employers. This article provides key background on VBID strategies, with a focus on T2DM management. It also provides a road map for health plans seeking to implement VBID as part of their programs.

  18. SCWR Concept in Canada

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2014-08-15

    AECL is designing the Canadian SCWR concept, which has evolved from the well-established pressuretube type CANDU® reactor. The Canadian SCWR is designed to produce electrical energy as the main product, plus process heat, hydrogen, industrial isotopes, and drinking water (through the desalination process) as supplementary products, all within a more compact reactor building. Another potential application of the available co-generated process heat is the extraction and refining of oil sands, which is presently achieved using co-generation with natural gas turbines and process heat. The extraction and upgrading process requires: thermal power to lower the viscosity and extract the oil; electric power for separation and refining equipment; and hydrogen gas for upgrading the oil product prior to transport. A National Program has been established in Canada to support R&D studies for the Canadian SCWR design. It covers key areas of interest (such as thermal hydraulics, safety, materials, and chemistry) to participants in the Generation-IV International Forum (GIF) SCWR designs. Results generated from the program are contributed to the GIF SCWR project management boards (PMBs). For example, heat transfer correlations have been derived using experimental data primarily obtained from fossil-plant related studies (which were started as early as 1930s. Materials and chemistry studies have evolved from operating experience of fossil-fired power plants to a) develop, and perform targeted testing of, materials for key components, in particular in-core reactor components that will be exposed to conditions not encountered in a fossil-fired boiler (such as irradiation and water radiolysis), and b) develop a suitable water chemistry to minimize corrosion and corrosion product transport.

  19. Evolving R Coronae Borealis Stars with MESA

    Science.gov (United States)

    Clayton, Geoffrey C.; Lauer, Amber; Chatzopoulos, Emmanouil; Frank, Juhan

    2018-01-01

    being a WD. Solving the mystery of how the RCB stars evolve will lead to a better understanding of other important types of stellar merger events such as Type Ia SNe.

  20. The evolving integrated vascular surgery residency curriculum.

    Science.gov (United States)

    Smith, Brigitte K; Greenberg, Jacob A; Mitchell, Erica L

    2014-10-01

    PDs voiced concern over the lack of standardization among the differing programs and most of the PDs agree that some degree of programmatic standardization is critical for the continued success of the 0 + 5 training paradigm. Qualitative evaluation of PD experiences with the development of 0 + 5 vascular surgery residency programs reveals the key factors that commonly influence program design. Programs continue to evolve in both structure and content as PDs respond to these influences. Learning from the collective experience of PDs and some standardization of the curricula may help current and future programs avoid common pitfalls in curricular development. Copyright © 2014 Elsevier Inc. All rights reserved.

  1. Mechanics of evolving thin film structures

    Science.gov (United States)

    Liang, Jim

    In the Stranski-Krastanov system, the lattice mismatch between the film and the substrate causes the film to break into islands. During annealing, both the surface energy and the elastic energy drive the islands to coarsen. Motivated by several related studies, we suggest that stable islands should form when a stiff ceiling is placed at a small gap above the film. We show that the role of elasticity is reversed: with the ceiling, the total elastic energy stored in the system increases as the islands coarsen laterally. Consequently, the islands select an equilibrium size to minimize the combined elastic energy and surface energy. In lithographically-induced self-assembly, when a two-phase fluid confined between parallel substrates is subjected to an electric field, one phase can self-assemble into a triangular lattice of islands in another phase. We describe a theory of the stability of the island lattice. The islands select the equilibrium diameter to minimize the combined interface energy and electrostatic energy. Furthermore, we study compressed SiGe thin film islands fabricated on a glass layer, which itself lies on a silicon wafer. Upon annealing, the glass flows, and the islands relax. A small island relaxes by in-plane expansion. A large island, however, wrinkles at the center before the in-plane relaxation arrives. The wrinkles may cause significant tensile stress in the island, leading to fracture. We model the island by the von Karman plate theory and the glass layer by the Reynolds lubrication theory. Numerical simulations evolve the in-plane expansion and the wrinkles simultaneously. We determine the critical island size, below which in-plane expansion prevails over wrinkling. Finally, in devices that integrate dissimilar materials in small dimensions, crack extension in one material often accompanies inelastic deformation in another. We analyze a channel crack advancing in an elastic film under tension, while an underlayer creeps. We use a two

  2. An Evolved System of Radiological Protection

    International Nuclear Information System (INIS)

    Kaneko, M.

    2004-01-01

    The current system of radiological protection based on the Linear No-Threshold (LNT) hypothesis has greatly contributed to the minimization of doses received by workers and members of the public. However, it has brought about r adiophobia a mong people and waste of resources due to over-regulation, because the LNT implies that radiation is harmful no matter how small the dose is. The author reviewed the results of research on health effects of radiation including major epidemiological studies on radiation workers and found no clear evidence of deleterious health effects from radiation exposures below the current maximum dose limits (50 mSv/y for workers and 5 mSv/y for members of the public), which have been adopted worldwide in the second half of the 20th century. Now that the existence of bio-defensive mechanisms such as DNA repair, apoptosis and adaptive response are well recognized, the linearity assumption cannot be said to be s cientific . Evidences increasingly imply that there are threshold effects in risk of radiation. A concept of practical thresholds or virtually safe doses will have to be introduced into the new system of radiological protection in order to resolve the low dose issues. Practical thresholds may be defined as dose levels below which induction of detectable radiogenic cancers or hereditary effects are not expected. If any workers and members of the public do not gain benefits from being exposed, excepting intentional irradiation for medical purposes, their radiation exposures should be kept below practical thresholds. On the assumption that the current dose limits are below practical thresholds and with no radiation detriments, there is no need of justification and optimization (ALARA) principles for occupational and public exposures. Then the ethical issue of justification to allow benefit to society to offset radiation detriments to individuals can be resolved. And also the ethical issue of optimization to exchange health or safety for

  3. Evolving Our Evaluation of Lighting Environments Project

    Science.gov (United States)

    Terrier, Douglas; Clayton, Ronald; Clark, Toni Anne

    2016-01-01

    Imagine you are an astronaut on their 100th day of your three year exploration mission. During your daily routine to the small hygiene compartment of the spacecraft, you realize that no matter what you do, your body blocks the light from the lamp. You can clearly see your hands or your toes but not both! What were those design engineers thinking! It would have been nice if they could have made the walls glow instead! The reason the designers were not more innovative is that their interpretation of the system lighting requirements didn't allow them to be so! Currently, our interior spacecraft lighting standards and requirements are written around the concept of a quantity of light illuminating a spacecraft surface. The natural interpretation for the engineer is that a lamp that throws light to the surface is required. Because of certification costs, only one lamp is designed and small rooms can wind up with lamps that may be inappropriate for the room architecture. The advances in solid state light emitting technologies and optics for lighting and visual communication necessitates the evaluation of how NASA envisions spacecraft lighting architectures and how NASA uses industry standards for the design and evaluation of lighting system. Current NASA lighting standards and requirements for existing architectures focus on the separate ability of a lighting system to throw light against a surface or the ability of a display system to provide the appropriate visual contrast. Realization that these systems can be integrated is not realized. The result is that the systems are developed independent from one another and potential efficiencies that could be realized from borrowing from the concept of one technology and applying it for the purpose of the other does not occur. This project investigated the possibility of incorporating large luminous surface lamps as an alternative or supplement to overhead lighting. We identified existing industry standards for architectural

  4. Study of the input-side subsurface reorganization vs. the outside current density in hydrogen permeation under constant cell voltage through iron membrane according to RHC concept

    International Nuclear Information System (INIS)

    DePetris-Wery, M.; Wery, S.; Catonne, J.C.

    2010-01-01

    In this work, hydrogen permeation tests were performed on pure iron membrane in 1 M sodium hydroxide at 298 K, subjected to hydrogen charging under 'quasi-potentiostatic' polarization conditions, i.e. constant cell voltage applied between the cathode (membrane entry side) and the anode (counter electrode), which is a typical situation during metal electrodeposition or cathodic degreasing on steel in metal finishing industry. Two consecutive charging-discharging runs were carried out. Prolonged hydrogen charging under quasi-potentiostatic polarization was investigated and the change of cathodic current density (i in ) chg and electrode potential (E in ) chg as well as permeation current density (i out ) chg were analysed. Three singularities were underlined for each experiment: (i) the curve (i in ) chg = f((E in ) chg ), illustrating the inverse of hydrogen charge resistance R HC -1 evolution which was negative, equal to zero and then became positive; (ii) quasi-periodic instabilities during the R HC -1 zero period, probably induced by atomic reorganizing due to subsurface hydrogen insertion in the input-side; (iii) the same ratio (i out ) chg /(i in ) chg = -6 x 10 -5 . During discharge runs, both sides of the membrane were polarized at the same potential (E in ) dischg = (E out ) dischg = -0.285 V/Hg/HgO/NaOH 1 M and the current densities, (i in ) dischg and (i out ) dischg which corresponded to the desorption rates of hydrogen, were measured. The following correlation (i out ) dischg vs.(i in ) dischg = -6 x 10 -5 was confirmed leading us to introduce the R HC -1 mirror concept to observe the input-side subsurface reorganization by the survey of its potential vs. outside current density during the hydrogen charge. Thus, this R HC -1 mirror concept showed: (i) a non-stop and irreversible progress in the subsurface reorganization during the two permeations; (ii) a probable structural evolution to a stable subsurface structure, the only condition of a real steady

  5. The Evolving Definition of the Term "Gene".

    Science.gov (United States)

    Portin, Petter; Wilkins, Adam

    2017-04-01

    This paper presents a history of the changing meanings of the term "gene," over more than a century, and a discussion of why this word, so crucial to genetics, needs redefinition today. In this account, the first two phases of 20th century genetics are designated the "classical" and the "neoclassical" periods, and the current molecular-genetic era the "modern period." While the first two stages generated increasing clarity about the nature of the gene, the present period features complexity and confusion. Initially, the term "gene" was coined to denote an abstract "unit of inheritance," to which no specific material attributes were assigned. As the classical and neoclassical periods unfolded, the term became more concrete, first as a dimensionless point on a chromosome, then as a linear segment within a chromosome, and finally as a linear segment in the DNA molecule that encodes a polypeptide chain. This last definition, from the early 1960s, remains the one employed today, but developments since the 1970s have undermined its generality. Indeed, they raise questions about both the utility of the concept of a basic "unit of inheritance" and the long implicit belief that genes are autonomous agents. Here, we review findings that have made the classic molecular definition obsolete and propose a new one based on contemporary knowledge. Copyright © 2017 by the Genetics Society of America.

  6. Star formation in evolving molecular clouds

    Science.gov (United States)

    Völschow, M.; Banerjee, R.; Körtgen, B.

    2017-09-01

    Molecular clouds are the principle stellar nurseries of our universe; they thus remain a focus of both observational and theoretical studies. From observations, some of the key properties of molecular clouds are well known but many questions regarding their evolution and star formation activity remain open. While numerical simulations feature a large number and complexity of involved physical processes, this plethora of effects may hide the fundamentals that determine the evolution of molecular clouds and enable the formation of stars. Purely analytical models, on the other hand, tend to suffer from rough approximations or a lack of completeness, limiting their predictive power. In this paper, we present a model that incorporates central concepts of astrophysics as well as reliable results from recent simulations of molecular clouds and their evolutionary paths. Based on that, we construct a self-consistent semi-analytical framework that describes the formation, evolution, and star formation activity of molecular clouds, including a number of feedback effects to account for the complex processes inside those objects. The final equation system is solved numerically but at much lower computational expense than, for example, hydrodynamical descriptions of comparable systems. The model presented in this paper agrees well with a broad range of observational results, showing that molecular cloud evolution can be understood as an interplay between accretion, global collapse, star formation, and stellar feedback.

  7. Evolution of design concepts for remotely maintainable equipment racks

    International Nuclear Information System (INIS)

    Peishel, F.L.; Mouring, R.W.; Schrock, S.L.

    1986-01-01

    Equipment racks have been used to support process equipment in radioactive facilities for many years. Improvements in the design of these racks have evolved relatively slowly primarily as a result of limitations in the capabilities of maintenance equipment; that is, tasks could only be approached from above using bridge cranes with viewing primarily through periscopes. In recent years, however, technological advances have been made by the Consolidated Fuel Reprocessing Program (CFRP) at Oak Ridge National Laboratory (ORNL) in bridge-mounted servomanipulators with onboard auxiliary hoists and television viewing systems. These advances permit full cell coverage by the manipulator arms which, in turn, allow maintenance tasks to be approached horizontally as well as from above. Maintainable equipment items can be stacked vertically on a rack because total overhead access is less important and maintenance tasks that would not have been attempted in the past can now be performed. These advances permit greater flexibility in the design and cell layout of the racks and lead to concepts that could significantly increase the availability of a facility. The evolution of rack design and a description of the alternative concepts based on present maintenance systems capabilities are presented in this paper. 13 refs., 11 figs

  8. Nonalcoholic fatty liver disease: Evolving paradigms

    Science.gov (United States)

    Lonardo, Amedeo; Nascimbeni, Fabio; Maurantonio, Mauro; Marrazzo, Alessandra; Rinaldi, Luca; Adinolfi, Luigi Elio

    2017-01-01

    In the last years new evidence has accumulated on nonalcoholic fatty liver disease (NAFLD) challenging the paradigms that had been holding the scene over the previous 30 years. NAFLD has such an epidemic prevalence as to make it impossible to screen general population looking for NAFLD cases. Conversely, focusing on those cohorts of individuals exposed to the highest risk of NAFLD could be a more rational approach. NAFLD, which can be diagnosed with either non-invasive strategies or through liver biopsy, is a pathogenically complex and clinically heterogeneous disease. The existence of metabolic as opposed to genetic-associated disease, notably including ”lean NAFLD” has recently been recognized. Moreover, NAFLD is a systemic condition, featuring metabolic, cardiovascular and (hepatic/extra-hepatic) cancer risk. Among the clinico-laboratory features of NAFLD we discuss hyperuricemia, insulin resistance, atherosclerosis, gallstones, psoriasis and selected endocrine derangements. NAFLD is a precursor of type 2 diabetes (T2D) and metabolic syndrome and progressive liver disease develops in T2D patients in whom the course of disease is worsened by NAFLD. Finally, lifestyle changes and drug treatment options to be implemented in the individual patient are also critically discussed. In conclusion, this review emphasizes the new concepts on clinical and pathogenic heterogeneity of NAFLD, a systemic disorder with a multifactorial pathogenesis and protean clinical manifestations. It is highly prevalent in certain cohorts of individuals who are thus potentially amenable to selective screening strategies, intensive follow-up schedules for early identification of liver-related and extrahepatic complications and in whom earlier and more aggressive treatment schedules should be carried out whenever possible. PMID:29085206

  9. GRI: focusing on the evolving violent universe

    Science.gov (United States)

    Knödlseder, Jürgen; von Ballmoos, Peter; Frontera, Filippo; Bazzano, Angela; Christensen, Finn; Hernanz, Margarida; Wunderer, Cornelia

    2009-03-01

    The gamma-ray imager (GRI) is a novel mission concept that will provide an unprecedented sensitivity leap in the soft gamma-ray domain by using for the first time a focusing lens built of Laue diffracting crystals. The lens will cover an energy band from 200-1,300 keV with an effective area reaching 600 cm2. It will be complemented by a single reflection multilayer coated mirror, extending the GRI energy band into the hard X-ray regime, down to ˜10 keV. The concentrated photons will be collected by a position sensitive pixelised CZT stack detector. We estimate continuum sensitivities of better than 10 - 7 ph cm - 2s - 1keV - 1 for a 100 ks exposure; the narrow line sensitivity will be better than 3 × 10 - 6 ph cm - 2s - 1 for the same integration time. As focusing instrument, GRI will have an angular resolution of better than 30 arcsec within a field of view of roughly 5 arcmin—an unprecedented achievement in the gamma-ray domain. Owing to the large focal length of 100 m of the lens and the mirror, the optics and detector will be placed on two separate spacecrafts flying in formation in a high elliptical orbit. R&D work to enable the lens focusing technology and to develop the required focal plane detector is currently underway, financed by ASI, CNES, ESA, and the Spanish Ministery of Education and Science. The GRI mission has been proposed as class M mission for ESAs Cosmic Vision 2015-2025 program. GRI will allow studies of particle acceleration processes and explosion physics in unprecedented detail, providing essential clues on the innermost nature of the most violent and most energetic processes in the universe.

  10. The genotype-phenotype map of an evolving digital organism.

    Directory of Open Access Journals (Sweden)

    Miguel A Fortuna

    2017-02-01

    Full Text Available To understand how evolving systems bring forth novel and useful phenotypes, it is essential to understand the relationship between genotypic and phenotypic change. Artificial evolving systems can help us understand whether the genotype-phenotype maps of natural evolving systems are highly unusual, and it may help create evolvable artificial systems. Here we characterize the genotype-phenotype map of digital organisms in Avida, a platform for digital evolution. We consider digital organisms from a vast space of 10141 genotypes (instruction sequences, which can form 512 different phenotypes. These phenotypes are distinguished by different Boolean logic functions they can compute, as well as by the complexity of these functions. We observe several properties with parallels in natural systems, such as connected genotype networks and asymmetric phenotypic transitions. The likely common cause is robustness to genotypic change. We describe an intriguing tension between phenotypic complexity and evolvability that may have implications for biological evolution. On the one hand, genotypic change is more likely to yield novel phenotypes in more complex organisms. On the other hand, the total number of novel phenotypes reachable through genotypic change is highest for organisms with simple phenotypes. Artificial evolving systems can help us study aspects of biological evolvability that are not accessible in vastly more complex natural systems. They can also help identify properties, such as robustness, that are required for both human-designed artificial systems and synthetic biological systems to be evolvable.

  11. The genotype-phenotype map of an evolving digital organism.

    Science.gov (United States)

    Fortuna, Miguel A; Zaman, Luis; Ofria, Charles; Wagner, Andreas

    2017-02-01

    To understand how evolving systems bring forth novel and useful phenotypes, it is essential to understand the relationship between genotypic and phenotypic change. Artificial evolving systems can help us understand whether the genotype-phenotype maps of natural evolving systems are highly unusual, and it may help create evolvable artificial systems. Here we characterize the genotype-phenotype map of digital organisms in Avida, a platform for digital evolution. We consider digital organisms from a vast space of 10141 genotypes (instruction sequences), which can form 512 different phenotypes. These phenotypes are distinguished by different Boolean logic functions they can compute, as well as by the complexity of these functions. We observe several properties with parallels in natural systems, such as connected genotype networks and asymmetric phenotypic transitions. The likely common cause is robustness to genotypic change. We describe an intriguing tension between phenotypic complexity and evolvability that may have implications for biological evolution. On the one hand, genotypic change is more likely to yield novel phenotypes in more complex organisms. On the other hand, the total number of novel phenotypes reachable through genotypic change is highest for organisms with simple phenotypes. Artificial evolving systems can help us study aspects of biological evolvability that are not accessible in vastly more complex natural systems. They can also help identify properties, such as robustness, that are required for both human-designed artificial systems and synthetic biological systems to be evolvable.

  12. An Evolving Asymmetric Game for Modeling Interdictor-Smuggler Problems

    Science.gov (United States)

    2016-06-01

    ASYMMETRIC GAME FOR MODELING INTERDICTOR-SMUGGLER PROBLEMS by Richard J. Allain June 2016 Thesis Advisor: David L. Alderson Second Reader: W...DATES COVERED Master’s thesis 4. TITLE AND SUBTITLE AN EVOLVING ASYMMETRIC GAME FOR MODELING INTERDICTOR- SMUGGLER PROBLEMS 5. FUNDING NUMBERS 6...NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS Approved for public release; distribution is unlimited AN EVOLVING

  13. Adaptation of Escherichia coli to glucose promotes evolvability in lactose.

    Science.gov (United States)

    Phillips, Kelly N; Castillo, Gerardo; Wünsche, Andrea; Cooper, Tim F

    2016-02-01

    The selective history of a population can influence its subsequent evolution, an effect known as historical contingency. We previously observed that five of six replicate populations that were evolved in a glucose-limited environment for 2000 generations, then switched to lactose for 1000 generations, had higher fitness increases in lactose than populations started directly from the ancestor. To test if selection in glucose systematically increased lactose evolvability, we started 12 replay populations--six from a population subsample and six from a single randomly selected clone--from each of the six glucose-evolved founder populations. These replay populations and 18 ancestral populations were evolved for 1000 generations in a lactose-limited environment. We found that replay populations were initially slightly less fit in lactose than the ancestor, but were more evolvable, in that they increased in fitness at a faster rate and to higher levels. This result indicates that evolution in the glucose environment resulted in genetic changes that increased the potential of genotypes to adapt to lactose. Genome sequencing identified four genes--iclR, nadR, spoT, and rbs--that were mutated in most glucose-evolved clones and are candidates for mediating increased evolvability. Our results demonstrate that short-term selective costs during selection in one environment can lead to changes in evolvability that confer longer term benefits. © 2016 The Author(s). Evolution © 2016 The Society for the Study of Evolution.

  14. PCBA demand forecasting using an evolving Takagi-Sugeno system

    NARCIS (Netherlands)

    van Rooijen, M.; Almeida, R.J.; Kaymak, U.

    2016-01-01

    This paper investigates the use of using an evolving fuzzy system for printed circuit board (PCBA) demand forecasting. The algorithm is based on the evolving Takagi-Sugeno (eTS) fuzzy system, which has the ability to incorporate new patterns by changing its internal structure in an on-line fashion.

  15. Investigation of a methanol reformer concept considering the particular impact of dynamics and long-term stability for use in a fuel-cell-powered passenger car

    Science.gov (United States)

    Peters, R.; Düsterwald, H. G.; Höhlein, B.

    A methanol reformer concept including a reformer, a catalytic burner, a gas cleaning unit, a PEMFC and an electric motor for use in fuel-cell-powered passenger cars was investigated. Special emphasis was placed on the dynamics and the long-term stability of the reformer. Experiments on a laboratory scale were performed in a methanol steam reformer consisting of four different reactor tubes, which were separately balanced. Due to the endothermy of the steam reforming reaction of methanol, a sharp drop in the reaction temperature of about 50 K occurs at the beginning of the catalyst bed. This agrees well with the high catalytic activity at the entrance of the catalyst bed. Forty-five percent of the methanol was converted within the first 10 cm of the catalyst bed where 12.6 g of the CuO/ZnO catalyst was located. Furthermore, CO formation during methanol steam reforming strongly depends on methanol conversion. Long-term measurements for more than 700 h show that the active reaction zone moved through the catalyst bed. Calculations, on the basis of these experiments, revealed that 63 g of reforming catalyst was necessary for mobile PEMFC applications, in this case for 400 W el at a system efficiency of 42% and a theoretical specific hydrogen production of 5.2 m 3n/(h kg Cat). This amount of catalyst was assumed to maintain a hydrogen production of at least 80% of the original amount over an operating range of 3864 h. Cycled start-up and shut-down processes of the methanol steam reformer under nitrogen and hydrogen atmospheres did not harm the catalytic activity. The simulation of the breakdown of the heating system, in which a liquid water/methanol mixture was in close contact with the catalyst, did not reveal any deactivation of the catalytic activity.

  16. Intracellular metabolite profiling of Saccharomyces cerevisiae evolved under furfural.

    Science.gov (United States)

    Jung, Young Hoon; Kim, Sooah; Yang, Jungwoo; Seo, Jin-Ho; Kim, Kyoung Heon

    2017-03-01

    Furfural, one of the most common inhibitors in pre-treatment hydrolysates, reduces the cell growth and ethanol production of yeast. Evolutionary engineering has been used as a selection scheme to obtain yeast strains that exhibit furfural tolerance. However, the response of Saccharomyces cerevisiae to furfural at the metabolite level during evolution remains unknown. In this study, evolutionary engineering and metabolomic analyses were applied to determine the effects of furfural on yeasts and their metabolic response to continuous exposure to furfural. After 50 serial transfers of cultures in the presence of furfural, the evolved strains acquired the ability to stably manage its physiological status under the furfural stress. A total of 98 metabolites were identified, and their abundance profiles implied that yeast metabolism was globally regulated. Under the furfural stress, stress-protective molecules and cofactor-related mechanisms were mainly induced in the parental strain. However, during evolution under the furfural stress, S. cerevisiae underwent global metabolic allocations to quickly overcome the stress, particularly by maintaining higher levels of metabolites related to energy generation, cofactor regeneration and recovery from cellular damage. Mapping the mechanisms of furfural tolerance conferred by evolutionary engineering in the present study will be led to rational design of metabolically engineered yeasts. © 2016 The Authors. Microbial Biotechnology published by John Wiley & Sons Ltd and Society for Applied Microbiology.

  17. Concept and cost of a pipeline system to supply hydrogen to fuel cell cars in Germany; Konzept und Kosten eines Pipelinesystems zur Versorgung des deutschen Strassenverkehrs mit Wasserstoff

    Energy Technology Data Exchange (ETDEWEB)

    Krieg, Dennis

    2012-11-01

    Fuel cells and hydrogen have the potential to be essential contributors for meeting the challenges of the future traffic sector. The key challenges include: - reducing global and local emissions - reducing import dependencies - preserving Germany's competitiveness - ensuring sufficient availability of the energy carrier Hydrogen is assumed to be the most appropriate energy carrier, since it can be produced via any primary energy and in terms of security is comparable to natural gas. In the long run, renewable energy, e.g. via wind power electrolysis, will make emission-free driving feasible. In order to use hydrogen to fuel cars, a comprehensive distribution infrastructure is required. This is completely different than the case of conventional fuels such as gasoline or diesel. Large amounts of hydrogen can be transported in a gaseous state in pipelines, as is common practice for natural gas. This option has not been examined to date. In particular, at the moment no suitable material has been identified for transporting hydrogen, which degrades the stability of the pipe. The aim of this thesis was to design a technical concept for a pipeline system that would make it possible to supply hydrogen to fuel cell cars. Using the assumptions of the study GermanHy, crucial technical questions were investigated. These questions comprise aspects such as general material requirements, feed-in, transportation and feed-out of the hydrogen. With respect to the material challenges, different potential possibilities are provided in order to ensure that no embrittlement will occur. Taking Germany as an example, the design and length of the pipeline system were investigated as well as the related economic and ecological aspects. A Monte Carlo simulation was conducted in order to calculate the probability density of both the investment and the specific cost. These results were placed in the overall context by calculating the economic impact of production, storage and fuelling stations

  18. Concept and cost of a pipeline system to supply hydrogen to fuel cell cars in Germany; Konzept und Kosten eines Pipelinesystems zur Versorgung des deutschen Strassenverkehrs mit Wasserstoff

    Energy Technology Data Exchange (ETDEWEB)

    Krieg, Dennis

    2012-11-01

    Fuel cells and hydrogen have the potential to be essential contributors for meeting the challenges of the future traffic sector. The key challenges include: - reducing global and local emissions - reducing import dependencies - preserving Germany's competitiveness - ensuring sufficient availability of the energy carrier Hydrogen is assumed to be the most appropriate energy carrier, since it can be produced via any primary energy and in terms of security is comparable to natural gas. In the long run, renewable energy, e.g. via wind power electrolysis, will make emission-free driving feasible. In order to use hydrogen to fuel cars, a comprehensive distribution infrastructure is required. This is completely different than the case of conventional fuels such as gasoline or diesel. Large amounts of hydrogen can be transported in a gaseous state in pipelines, as is common practice for natural gas. This option has not been examined to date. In particular, at the moment no suitable material has been identified for transporting hydrogen, which degrades the stability of the pipe. The aim of this thesis was to design a technical concept for a pipeline system that would make it possible to supply hydrogen to fuel cell cars. Using the assumptions of the study GermanHy, crucial technical questions were investigated. These questions comprise aspects such as general material requirements, feed-in, transportation and feed-out of the hydrogen. With respect to the material challenges, different potential possibilities are provided in order to ensure that no embrittlement will occur. Taking Germany as an example, the design and length of the pipeline system were investigated as well as the related economic and ecological aspects. A Monte Carlo simulation was conducted in order to calculate the probability density of both the investment and the specific cost. These results were placed in the overall context by calculating the economic impact of production, storage and fuelling

  19. Laplacian Estrada and normalized Laplacian Estrada indices of evolving graphs.

    Directory of Open Access Journals (Sweden)

    Yilun Shang

    Full Text Available Large-scale time-evolving networks have been generated by many natural and technological applications, posing challenges for computation and modeling. Thus, it is of theoretical and practical significance to probe mathematical tools tailored for evolving networks. In this paper, on top of the dynamic Estrada index, we study the dynamic Laplacian Estrada index and the dynamic normalized Laplacian Estrada index of evolving graphs. Using linear algebra techniques, we established general upper and lower bounds for these graph-spectrum-based invariants through a couple of intuitive graph-theoretic measures, including the number of vertices or edges. Synthetic random evolving small-world networks are employed to show the relevance of the proposed dynamic Estrada indices. It is found that neither the static snapshot graphs nor the aggregated graph can approximate the evolving graph itself, indicating the fundamental difference between the static and dynamic Estrada indices.

  20. Laplacian Estrada and normalized Laplacian Estrada indices of evolving graphs.

    Science.gov (United States)

    Shang, Yilun

    2015-01-01

    Large-scale time-evolving networks have been generated by many natural and technological applications, posing challenges for computation and modeling. Thus, it is of theoretical and practical significance to probe mathematical tools tailored for evolving networks. In this paper, on top of the dynamic Estrada index, we study the dynamic Laplacian Estrada index and the dynamic normalized Laplacian Estrada index of evolving graphs. Using linear algebra techniques, we established general upper and lower bounds for these graph-spectrum-based invariants through a couple of intuitive graph-theoretic measures, including the number of vertices or edges. Synthetic random evolving small-world networks are employed to show the relevance of the proposed dynamic Estrada indices. It is found that neither the static snapshot graphs nor the aggregated graph can approximate the evolving graph itself, indicating the fundamental difference between the static and dynamic Estrada indices.

  1. Mathematical concepts

    CERN Document Server

    Jost, Jürgen

    2015-01-01

    The main intention of this book is to describe and develop the conceptual, structural and abstract thinking of mathematics. Specific mathematical structures are used to illustrate the conceptual approach; providing a deeper insight into mutual relationships and abstract common features. These ideas are carefully motivated, explained and illustrated by examples so that many of the more technical proofs can be omitted. The book can therefore be used: ·         simply as an overview of the panorama of mathematical structures and the relations between them, to be supplemented by more detailed texts whenever you want to acquire a working knowledge of some structure ·         by itself as a first introduction to abstract mathematics ·         together with existing textbooks, to put their results into a more general perspective ·         to gain a new and hopefully deeper perspective after having studied such textbooks Mathematical Concepts has a broader scope and is less detaile...

  2. Evolving Marine Biomimetics for Regenerative Dentistry

    Science.gov (United States)

    Green, David W.; Lai, Wing-Fu; Jung, Han-Sung

    2014-01-01

    New products that help make human tissue and organ regeneration more effective are in high demand and include materials, structures and substrates that drive cell-to-tissue transformations, orchestrate anatomical assembly and tissue integration with biology. Marine organisms are exemplary bioresources that have extensive possibilities in supporting and facilitating development of human tissue substitutes. Such organisms represent a deep and diverse reserve of materials, substrates and structures that can facilitate tissue reconstruction within lab-based cultures. The reason is that they possess sophisticated structures, architectures and biomaterial designs that are still difficult to replicate using synthetic processes, so far. These products offer tantalizing pre-made options that are versatile, adaptable and have many functions for current tissue engineers seeking fresh solutions to the deficiencies in existing dental biomaterials, which lack the intrinsic elements of biofunctioning, structural and mechanical design to regenerate anatomically correct dental tissues both in the culture dish and in vivo. PMID:24828293

  3. Evolving Marine Biomimetics for Regenerative Dentistry

    Directory of Open Access Journals (Sweden)

    David W. Green

    2014-05-01

    Full Text Available New products that help make human tissue and organ regeneration more effective are in high demand and include materials, structures and substrates that drive cell-to-tissue transformations, orchestrate anatomical assembly and tissue integration with biology. Marine organisms are exemplary bioresources that have extensive possibilities in supporting and facilitating development of human tissue substitutes. Such organisms represent a deep and diverse reserve of materials, substrates and structures that can facilitate tissue reconstruction within lab-based cultures. The reason is that they possess sophisticated structures, architectures and biomaterial designs that are still difficult to replicate using synthetic processes, so far. These products offer tantalizing pre-made options that are versatile, adaptable and have many functions for current tissue engineers seeking fresh solutions to the deficiencies in existing dental biomaterials, which lack the intrinsic elements of biofunctioning, structural and mechanical design to regenerate anatomically correct dental tissues both in the culture dish and in vivo.

  4. Revisiting Robustness and Evolvability: Evolution in Weighted Genotype Spaces

    Science.gov (United States)

    Partha, Raghavendran; Raman, Karthik

    2014-01-01

    Robustness and evolvability are highly intertwined properties of biological systems. The relationship between these properties determines how biological systems are able to withstand mutations and show variation in response to them. Computational studies have explored the relationship between these two properties using neutral networks of RNA sequences (genotype) and their secondary structures (phenotype) as a model system. However, these studies have assumed every mutation to a sequence to be equally likely; the differences in the likelihood of the occurrence of various mutations, and the consequence of probabilistic nature of the mutations in such a system have previously been ignored. Associating probabilities to mutations essentially results in the weighting of genotype space. We here perform a comparative analysis of weighted and unweighted neutral networks of RNA sequences, and subsequently explore the relationship between robustness and evolvability. We show that assuming an equal likelihood for all mutations (as in an unweighted network), underestimates robustness and overestimates evolvability of a system. In spite of discarding this assumption, we observe that a negative correlation between sequence (genotype) robustness and sequence evolvability persists, and also that structure (phenotype) robustness promotes structure evolvability, as observed in earlier studies using unweighted networks. We also study the effects of base composition bias on robustness and evolvability. Particularly, we explore the association between robustness and evolvability in a sequence space that is AU-rich – sequences with an AU content of 80% or higher, compared to a normal (unbiased) sequence space. We find that evolvability of both sequences and structures in an AU-rich space is lesser compared to the normal space, and robustness higher. We also observe that AU-rich populations evolving on neutral networks of phenotypes, can access less phenotypic variation compared to

  5. Brain mesenchymal stem cells: physiology and pathological implications.

    Science.gov (United States)

    Pombero, Ana; Garcia-Lopez, Raquel; Martinez, Salvador

    2016-06-01

    Mesenchymal stem cells (MSCs) are defined as progenitor cells that give rise to a number of unique, differentiated mesenchymal cell types. This concept has progressively evolved towards an all-encompassing concept including multipotent perivascular cells of almost any tissue. In central nervous system, pericytes are involved in blood-brain barrier, and angiogenesis and vascular tone regulation. They form the neurovascular unit (NVU) together with endothelial cells, astrocytes and neurons. This functional structure provides an optimal microenvironment for neural proliferation in the adult brain. Neurovascular niche include both diffusible signals and direct contact with endothelial and pericytes, which are a source of diffusible neurotrophic signals that affect neural precursors. Therefore, MSCs/pericyte properties such as differentiation capability, as well as immunoregulatory and paracrine effects make them a potential resource in regenerative medicine. © 2016 Japanese Society of Developmental Biologists.

  6. Homophyly/Kinship Model: Naturally Evolving Networks

    Science.gov (United States)

    Li, Angsheng; Li, Jiankou; Pan, Yicheng; Yin, Xianchen; Yong, Xi

    2015-10-01

    It has been a challenge to understand the formation and roles of social groups or natural communities in the evolution of species, societies and real world networks. Here, we propose the hypothesis that homophyly/kinship is the intrinsic mechanism of natural communities, introduce the notion of the affinity exponent and propose the homophyly/kinship model of networks. We demonstrate that the networks of our model satisfy a number of topological, probabilistic and combinatorial properties and, in particular, that the robustness and stability of natural communities increase as the affinity exponent increases and that the reciprocity of the networks in our model decreases as the affinity exponent increases. We show that both homophyly/kinship and reciprocity are essential to the emergence of cooperation in evolutionary games and that the homophyly/kinship and reciprocity determined by the appropriate affinity exponent guarantee the emergence of cooperation in evolutionary games, verifying Darwin’s proposal that kinship and reciprocity are the means of individual fitness. We propose the new principle of structure entropy minimisation for detecting natural communities of networks and verify the functional module property and characteristic properties by a healthy tissue cell network, a citation network, some metabolic networks and a protein interaction network.

  7. Evolvable Mars Campaign Long Duration Habitation Strategies: Architectural Approaches to Enable Human Exploration Missions

    Science.gov (United States)

    Simon, Matthew A.; Toups, Larry; Howe, A. Scott; Wald, Samuel I.

    2015-01-01

    The Evolvable Mars Campaign (EMC) is the current NASA Mars mission planning effort which seeks to establish sustainable, realistic strategies to enable crewed Mars missions in the mid-2030s timeframe. The primary outcome of the Evolvable Mars Campaign is not to produce "The Plan" for sending humans to Mars, but instead its intent is to inform the Human Exploration and Operations Mission Directorate near-term key decisions and investment priorities to prepare for those types of missions. The FY'15 EMC effort focused upon analysis of integrated mission architectures to identify technically appealing transportation strategies, logistics build-up strategies, and vehicle designs for reaching and exploring Mars moons and Mars surface. As part of the development of this campaign, long duration habitats are required which are capable of supporting crew with limited resupply and crew abort during the Mars transit, Mars moons, and Mars surface segments of EMC missions. In particular, the EMC design team sought to design a single, affordable habitation system whose manufactured units could be outfitted uniquely for each of these missions and reused for multiple crewed missions. This habitat system must provide all of the functionality to safely support 4 crew for long durations while meeting mass and volume constraints for each of the mission segments set by the chosen transportation architecture and propulsion technologies. This paper describes several proposed long-duration habitation strategies to enable the Evolvable Mars Campaign through improvements in mass, cost, and reusability, and presents results of analysis to compare the options and identify promising solutions. The concepts investigated include several monolithic concepts: monolithic clean sheet designs, and concepts which leverage the co-manifested payload capability of NASA's Space Launch System (SLS) to deliver habitable elements within the Universal Payload Adaptor between the SLS upper stage and the Orion

  8. High somatic cell counts and changes in milk fat and protein contents around insemination are negatively associated with conception in dairy cows

    OpenAIRE

    Albaaj, Ahmad; Foucras, Gilles; Raboisson, Didier

    2017-01-01

    The fertility of dairy cows has decreased dramatically worldwide over the last few decades, and several causes of this trend have been reported. Several studies have associated compromised udder health with deteriorating reproduction performance. Subclinical ketosis (SCK) has also been reported to be a risk factor for decreased conception. The objective of the present study was to describe how SCK might interact with the reported association between udder health and conception in dairy cows. ...

  9. Fourth Generation Reactor Concepts

    International Nuclear Information System (INIS)

    Furtek, A.

    2008-01-01

    Concerns over energy resources availability, climate changes and energy supply security suggest an important role for nuclear energy in future energy supplies. So far nuclear energy evolved through three generations and is still evolving into new generation that is now being extensively studied. Nuclear Power Plants are producing 16% of the world's electricity. Today the world is moving towards hydrogen economy. Nuclear technologies can provide energy to dissociate water into oxygen and hydrogen and to production of synthetic fuel from coal gasification. The introduction of breeder reactors would turn nuclear energy from depletable energy supply into an unlimited supply. From the early beginnings of nuclear energy in the 1940s to the present, three generations of nuclear power reactors have been developed: First generation reactors: introduced during the period 1950-1970. Second generation: includes commercial power reactors built during 1970-1990 (PWR, BWR, Candu, Russian RBMK and VVER). Third generation: started being deployed in the 1990s and is composed of Advanced LWR (ALWR), Advanced BWR (ABWR) and Passive AP600 to be deployed in 2010-2030. Future advances of the nuclear technology designs can broaden opportunities for use of nuclear energy. The fourth generation reactors are expected to be deployed by 2030 in time to replace ageing reactors built in the 1970s and 1980s. The new reactors are to be designed with a view of the following objectives: economic competitiveness, enhanced safety, minimal radioactive waste production, proliferation resistance. The Generation IV International Forum (GIF) was established in January 2000 to investigate innovative nuclear energy system concepts. GIF members include Argentina, Brazil, Canada, Euratom, France Japan, South Africa, South Korea, Switzerland, United Kingdom and United States with the IAEA and OECD's NEA as permanent observers. China and Russia are expected to join the GIF initiative. The following six systems

  10. Digital Competence--An Emergent Boundary Concept for Policy and Educational Research

    Science.gov (United States)

    Ilomäki, Liisa; Paavola, Sami; Lakkala, Minna; Kantosalo, Anna

    2016-01-01

    Digital competence is an evolving concept related to the development of digital technology and the political aims and expectations of citizenship in a knowledge society. It is regarded as a core competence in policy papers; in educational research it is not yet a standardized concept. We suggest that it is a useful boundary concept, which can be…

  11. Concepts and introduction to RNA bioinformatics

    DEFF Research Database (Denmark)

    Gorodkin, Jan; Hofacker, Ivo L.; Ruzzo, Walter L.

    2014-01-01

    RNA bioinformatics and computational RNA biology have emerged from implementing methods for predicting the secondary structure of single sequences. The field has evolved to exploit multiple sequences to take evolutionary information into account, such as compensating (and structure preserving) base...... for interactions between RNA and proteins.Here, we introduce the basic concepts of predicting RNA secondary structure relevant to the further analyses of RNA sequences. We also provide pointers to methods addressing various aspects of RNA bioinformatics and computational RNA biology....

  12. Current concepts in blood glucose monitoring

    OpenAIRE

    Khadilkar, Kranti Shreesh; Bandgar, Tushar; Shivane, Vyankatesh; Lila, Anurag; Shah, Nalini

    2013-01-01

    Blood glucose monitoring has evolved over the last century. The concept of adequate glycemic control and minimum glycemic variability requires an ideal, accurate and reliable glucose monitoring system. The search for an ideal blood glucose monitoring system still continues. This review explains the various blood glucose monitoring systems with special focus on the monitoring systems like self- monitored blood glucose (SMBG) and continuous glucose monitoring system (CGMS). It also focuses on t...

  13. Project Seahorse evolves into major marine protector | IDRC ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    2012-10-29

    Oct 29, 2012 ... Project Seahorse evolves into major marine protector ... local people, have greatly improved the prospects of survival for threatened species. ... “We tackle issues on any political level or geographical scale, according to what ...

  14. Incremental Frequent Subgraph Mining on Large Evolving Graphs

    KAUST Repository

    Abdelhamid, Ehab; Canim, Mustafa; Sadoghi, Mohammad; Bhatta, Bishwaranjan; Chang, Yuan-Chi; Kalnis, Panos

    2017-01-01

    , such as social networks, utilize large evolving graphs. Mining these graphs using existing techniques is infeasible, due to the high computational cost. In this paper, we propose IncGM+, a fast incremental approach for continuous frequent subgraph mining problem

  15. Genetic Algorithms Evolve Optimized Transforms for Signal Processing Applications

    National Research Council Canada - National Science Library

    Moore, Frank; Babb, Brendan; Becke, Steven; Koyuk, Heather; Lamson, Earl, III; Wedge, Christopher

    2005-01-01

    .... The primary goal of the research described in this final report was to establish a methodology for using genetic algorithms to evolve coefficient sets describing inverse transforms and matched...

  16. Orthogonally Evolved AI to Improve Difficulty Adjustment in Video Games

    DEFF Research Database (Denmark)

    Hintze, Arend; Olson, Randal; Lehman, Joel Anthony

    2016-01-01

    Computer games are most engaging when their difficulty is well matched to the player's ability, thereby providing an experience in which the player is neither overwhelmed nor bored. In games where the player interacts with computer-controlled opponents, the difficulty of the game can be adjusted...... not only by changing the distribution of opponents or game resources, but also through modifying the skill of the opponents. Applying evolutionary algorithms to evolve the artificial intelligence that controls opponent agents is one established method for adjusting opponent difficulty. Less-evolved agents...... (i.e. agents subject to fewer generations of evolution) make for easier opponents, while highly-evolved agents are more challenging to overcome. In this publication we test a new approach for difficulty adjustment in games: orthogonally evolved AI, where the player receives support from collaborating...

  17. Evolving the Evolving: Territory, Place and Rewilding in the California Delta

    Directory of Open Access Journals (Sweden)

    Brett Milligan

    2017-10-01

    Full Text Available Current planning and legislation in California’s Sacramento-San Joaquin Delta call for the large-scale ecological restoration of aquatic and terrestrial habitats. These ecological mandates have emerged in response to the region’s infrastructural transformation and the Delta’s predominant use as the central logistical hub in the state’s vast water conveyance network. Restoration is an attempt to recover what was externalized by the logic and abstractions of this logistical infrastructure. However, based on findings from our research, which examined how people are using restored and naturalized landscapes in the Delta and how these landscapes are currently planned for, we argue that as mitigatory response, restoration planning continues some of the same spatial abstractions and inequities by failing to account for the Delta as an urbanized, cultural and unique place. In interpreting how these conditions have come to be, we give attention to a pluralistic landscape approach and a coevolutionary reading of planning, policy, science and landscapes to discuss the conservation challenges presented by “Delta as an Evolving Place”. We suggest that for rewilding efforts to be successful in the Delta, a range of proactive, opportunistic, grounded and participatory tactics will be required to shift towards a more socio-ecological approach.

  18. Surrogate-assisted identification of influences of network construction on evolving weighted functional networks

    Science.gov (United States)

    Stahn, Kirsten; Lehnertz, Klaus

    2017-12-01

    We aim at identifying factors that may affect the characteristics of evolving weighted networks derived from empirical observations. To this end, we employ various chains of analysis that are often used in field studies for a data-driven derivation and characterization of such networks. As an example, we consider fully connected, weighted functional brain networks before, during, and after epileptic seizures that we derive from multichannel electroencephalographic data recorded from epilepsy patients. For these evolving networks, we estimate clustering coefficient and average shortest path length in a time-resolved manner. Lastly, we make use of surrogate concepts that we apply at various levels of the chain of analysis to assess to what extent network characteristics are dominated by properties of the electroencephalographic recordings and/or the evolving weighted networks, which may be accessible more easily. We observe that characteristics are differently affected by the unavoidable referencing of the electroencephalographic recording, by the time-series-analysis technique used to derive the properties of network links, and whether or not networks were normalized. Importantly, for the majority of analysis settings, we observe temporal evolutions of network characteristics to merely reflect the temporal evolutions of mean interaction strengths. Such a property of the data may be accessible more easily, which would render the weighted network approach—as used here—as an overly complicated description of simple aspects of the data.

  19. Current concepts in blood glucose monitoring.

    Science.gov (United States)

    Khadilkar, Kranti Shreesh; Bandgar, Tushar; Shivane, Vyankatesh; Lila, Anurag; Shah, Nalini

    2013-12-01

    Blood glucose monitoring has evolved over the last century. The concept of adequate glycemic control and minimum glycemic variability requires an ideal, accurate and reliable glucose monitoring system. The search for an ideal blood glucose monitoring system still continues. This review explains the various blood glucose monitoring systems with special focus on the monitoring systems like self- monitored blood glucose (SMBG) and continuous glucose monitoring system (CGMS). It also focuses on the newer concepts of blood glucose monitoring and their incorporation in routine clinical management of diabetes mellitus.

  20. Current concepts in blood glucose monitoring

    Science.gov (United States)

    Khadilkar, Kranti Shreesh; Bandgar, Tushar; Shivane, Vyankatesh; Lila, Anurag; Shah, Nalini

    2013-01-01

    Blood glucose monitoring has evolved over the last century. The concept of adequate glycemic control and minimum glycemic variability requires an ideal, accurate and reliable glucose monitoring system. The search for an ideal blood glucose monitoring system still continues. This review explains the various blood glucose monitoring systems with special focus on the monitoring systems like self- monitored blood glucose (SMBG) and continuous glucose monitoring system (CGMS). It also focuses on the newer concepts of blood glucose monitoring and their incorporation in routine clinical management of diabetes mellitus. PMID:24910827

  1. Current concepts in blood glucose monitoring

    Directory of Open Access Journals (Sweden)

    Kranti Shreesh Khadilkar

    2013-01-01

    Full Text Available Blood glucose monitoring has evolved over the last century. The concept of adequate glycemic control and minimum glycemic variability requires an ideal, accurate and reliable glucose monitoring system. The search for an ideal blood glucose monitoring system still continues. This review explains the various blood glucose monitoring systems with special focus on the monitoring systems like self- monitored blood glucose (SMBG and continuous glucose monitoring system (CGMS. It also focuses on the newer concepts of blood glucose monitoring and their incorporation in routine clinical management of diabetes mellitus.

  2. (N+1)-dimensional Lorentzian evolving wormholes supported by polytropic matter

    Energy Technology Data Exchange (ETDEWEB)

    Cataldo, Mauricio [Universidad del Bio-Bio, Departamento de Fisica, Facultad de Ciencias, Concepcion (Chile); Arostica, Fernanda; Bahamonde, Sebastian [Universidad de Concepcion, Departamento de Fisica, Concepcion (Chile)

    2013-08-15

    In this paper we study (N+1)-dimensional evolving wormholes supported by energy satisfying a polytropic equation of state. The considered evolving wormhole models are described by a constant redshift function and generalizes the standard flat Friedmann-Robertson-Walker spacetime. The polytropic equation of state allows us to consider in (3+1)-dimensions generalizations of the phantom energy and the generalized Chaplygin gas sources. (orig.)

  3. From Perceptual Categories to Concepts: What Develops?

    Science.gov (United States)

    Sloutsky, Vladimir M.

    2010-01-01

    People are remarkably smart: they use language, possess complex motor skills, make non-trivial inferences, develop and use scientific theories, make laws, and adapt to complex dynamic environments. Much of this knowledge requires concepts and this paper focuses on how people acquire concepts. It is argued that conceptual development progresses from simple perceptual grouping to highly abstract scientific concepts. This proposal of conceptual development has four parts. First, it is argued that categories in the world have different structure. Second, there might be different learning systems (sub-served by different brain mechanisms) that evolved to learn categories of differing structures. Third, these systems exhibit differential maturational course, which affects how categories of different structures are learned in the course of development. And finally, an interaction of these components may result in the developmental transition from perceptual groupings to more abstract concepts. This paper reviews a large body of empirical evidence supporting this proposal. PMID:21116483

  4. Modular Orbital Demonstration of an Evolvable Space Telescope (MODEST)

    Science.gov (United States)

    Baldauf, Brian; Conti, Alberto

    2016-01-01

    The "Search for Life" via imaging of exoplanets is a mission that requires extremely stable telescopes with apertures in the 10 m to 20 m range. The High Definition Space Telescope (HDST) envisioned for this mission would have an aperture >10 m, which is a larger payload than what can be delivered to space using a single launch vehicle. Building and assembling the mirror segments enabling large telescopes will likely require multiple launches and assembly in space. Space-based telescopes with large apertures will require major changes to system architectures.The Optical Telescope Assembly (OTA) for HDST is a primary mission cost driver. Enabling and affordable solutions for this next generation of large aperture space-based telescope are needed.This paper reports on the concept for the Modular Orbital Demonstration of an Evolvable Space Telescope (MODEST), which demonstrates on-orbit robotic and/or astronaut assembly of a precision optical telescope in space. It will also facilitate demonstration of active correction of phase and mirror shape. MODEST is proposed to be delivered to the ISS using standard Express Logistics Carriers (ELCs) and can mounted to one of a variety of ISS pallets. Post-assembly value includes space, ground, and environmental studies, and a testbed for new instruments. This demonstration program for next generation mirror technology provides significant risk reduction and demonstrates the technology in a six-mirror phased telescope. Other key features of the demonstration include the use of an active primary optical surface with wavefront feedback control that allows on-orbit optimization and demonstration of precise surface control to meet optical system wavefront and stability requirements.MODEST will also be used to evaluate advances in lightweight mirror and metering structure materials such as SiC or Carbon Fiber Reinforced Polymer that have excellent mechanical and thermal properties, e.g. high stiffness, high modulus, high thermal

  5. A new evolutionary system for evolving artificial neural networks.

    Science.gov (United States)

    Yao, X; Liu, Y

    1997-01-01

    This paper presents a new evolutionary system, i.e., EPNet, for evolving artificial neural networks (ANNs). The evolutionary algorithm used in EPNet is based on Fogel's evolutionary programming (EP). Unlike most previous studies on evolving ANN's, this paper puts its emphasis on evolving ANN's behaviors. Five mutation operators proposed in EPNet reflect such an emphasis on evolving behaviors. Close behavioral links between parents and their offspring are maintained by various mutations, such as partial training and node splitting. EPNet evolves ANN's architectures and connection weights (including biases) simultaneously in order to reduce the noise in fitness evaluation. The parsimony of evolved ANN's is encouraged by preferring node/connection deletion to addition. EPNet has been tested on a number of benchmark problems in machine learning and ANNs, such as the parity problem, the medical diagnosis problems, the Australian credit card assessment problem, and the Mackey-Glass time series prediction problem. The experimental results show that EPNet can produce very compact ANNs with good generalization ability in comparison with other algorithms.

  6. canEvolve: a web portal for integrative oncogenomics.

    Directory of Open Access Journals (Sweden)

    Mehmet Kemal Samur

    Full Text Available BACKGROUND & OBJECTIVE: Genome-wide profiles of tumors obtained using functional genomics platforms are being deposited to the public repositories at an astronomical scale, as a result of focused efforts by individual laboratories and large projects such as the Cancer Genome Atlas (TCGA and the International Cancer Genome Consortium. Consequently, there is an urgent need for reliable tools that integrate and interpret these data in light of current knowledge and disseminate results to biomedical researchers in a user-friendly manner. We have built the canEvolve web portal to meet this need. RESULTS: canEvolve query functionalities are designed to fulfill most frequent analysis needs of cancer researchers with a view to generate novel hypotheses. canEvolve stores gene, microRNA (miRNA and protein expression profiles, copy number alterations for multiple cancer types, and protein-protein interaction information. canEvolve allows querying of results of primary analysis, integrative analysis and network analysis of oncogenomics data. The querying for primary analysis includes differential gene and miRNA expression as well as changes in gene copy number measured with SNP microarrays. canEvolve provides results of integrative analysis of gene expression profiles with copy number alterations and with miRNA profiles as well as generalized integrative analysis using gene set enrichment analysis. The network analysis capability includes storage and visualization of gene co-expression, inferred gene regulatory networks and protein-protein interaction information. Finally, canEvolve provides correlations between gene expression and clinical outcomes in terms of univariate survival analysis. CONCLUSION: At present canEvolve provides different types of information extracted from 90 cancer genomics studies comprising of more than 10,000 patients. The presence of multiple data types, novel integrative analysis for identifying regulators of oncogenesis, network

  7. Is plate tectonics needed to evolve technological species on exoplanets?

    Directory of Open Access Journals (Sweden)

    Robert J. Stern

    2016-07-01

    Full Text Available As we continue searching for exoplanets, we wonder if life and technological species capable of communicating with us exists on any of them. As geoscientists, we can also wonder how important is the presence or absence of plate tectonics for the evolution of technological species. This essay considers this question, focusing on tectonically active rocky (silicate planets, like Earth, Venus, and Mars. The development of technological species on Earth provides key insights for understanding evolution on exoplanets, including the likely role that plate tectonics may play. An Earth-sized silicate planet is likely to experience several tectonic styles over its lifetime, as it cools and its lithosphere thickens, strengthens, and becomes denser. These include magma ocean, various styles of stagnant lid, and perhaps plate tectonics. Abundant liquid water favors both life and plate tectonics. Ocean is required for early evolution of diverse single-celled organisms, then colonies of cells which specialized further to form guts, appendages, and sensory organisms up to the complexity of fish (central nervous system, appendages, eyes. Large expanses of dry land also begin in the ocean, today produced above subduction zones in juvenile arcs and by their coalescence to form continents, although it is not clear that plate tectonics was required to create continental crust on Earth. Dry land of continents is required for further evolution of technological species, where modification of appendages for grasping and manipulating, and improvement of eyes and central nervous system could be perfected. These bioassets allowed intelligent creatures to examine the night sky and wonder, the beginning of abstract thinking, including religion and science. Technology arises from the exigencies of daily living such as tool-making, agriculture, clothing, and weapons, but the pace of innovation accelerates once it is allied with science. Finally, the importance of plate

  8. Status and promise of fuel cell technology

    Energy Technology Data Exchange (ETDEWEB)

    Williams, M.C. [National Energy Technology Lab., Pittsburgh, PA (United States). Dept. of Energy

    2001-09-01

    The niche or early entry market penetration by ONSI and its phosphoric acid fuel cell technology has proven that fuel cells are reliable and suitable for premium power and other opportunity fuel niche market applications. Now, new fuel cell technologies - solid oxide fuel cells, molten carbonate fuel cells, and polymer electrolyte fuel cells - are being developed for near-term distributed generation shortly after 2003. Some of the evolving fuel cell systems are incorporating gas turbines in hybrid configurations. The combination of the gas turbine with the fuel cell promises to lower system costs and increase efficiency to enhance market penetration. Market estimates indicate that significant early entry markets exist to sustain the initially high cost of some distributed generation technologies. However, distributed generation technologies must have low introductory first cost, low installation cost, and high system reliability to be viable options in competitive commercial and industrial markets. In the long-term, solid state fuel cell technology with stack costs under $100/kilowatt (kW) promises deeper and wider market penetration in a range of applications including a residential, auxillary power, and the mature distributed generation markets. The solid state energy conversion alliance (SECA) with its vision for fuel cells in 2010 was recently formed to commercialize solid state fuel cells and realize the full potential of the fuel cell technology. Ultimately, the SECA concept could lead to megawatt-size fuel-cell systems for commercial and industrial applications and Vision 21 fuel cell turbine hybrid energy plants in 2015. (orig.)

  9. Innate B cells: oxymoron or validated concept? [v1; ref status: indexed, http://f1000r.es/T4CAVP

    Directory of Open Access Journals (Sweden)

    Carl F Ware

    2012-08-01

    Full Text Available B lymphocytes promote the initial innate interferon response to viral pathogens without the need for antigen receptor activation. B cell dependent IFN production requires the cytokine, lymphotoxin-β. The LTβ pathway is well known to regulate lymphoid organogenesis and homeostasis by differentiating stromal cells and macrophages. However, in response to viral pathogens these same B cell-regulated populations rapidly produce type 1 interferons. Thus, B cells act as innate effector cells via LTβ homeostatic pathways, which serve as innate host barriers to viral pathogens.

  10. Alternative cask maintenance facility concepts

    International Nuclear Information System (INIS)

    Attaway, C.R.; Pope, R.B.; Wiliamson, A.C.; Medley, L.G.; Shappert, L.B.

    1992-01-01

    In this paper, the results of three trade-off studies of alternative concepts for performing cask maintenance for Civilian Radioactive Waste Management System casks are presented. An earlier study resulted in a recommendation that a submerged pool concept for cask internal component removal be used in the design of a Cask Maintenance Facility. The first trade-off study resulted in confirming the previous recommendation that a submerged pool concept be used rather than an isolation cell; the basis for this continued recommendation is discussed. The second study provides an evaluation of the previously proposed facility for the capability of handling an increased quantity of OCRWM casks. The third study provides a preliminary concept for adding the capability to repaint the exterior cylindrical portions of casks

  11. Modeling and clustering users with evolving profiles in usage streams

    KAUST Repository

    Zhang, Chongsheng

    2012-09-01

    Today, there is an increasing need of data stream mining technology to discover important patterns on the fly. Existing data stream models and algorithms commonly assume that users\\' records or profiles in data streams will not be updated or revised once they arrive. Nevertheless, in various applications such asWeb usage, the records/profiles of the users can evolve along time. This kind of streaming data evolves in two forms, the streaming of tuples or transactions as in the case of traditional data streams, and more importantly, the evolving of user records/profiles inside the streams. Such data streams bring difficulties on modeling and clustering for exploring users\\' behaviors. In this paper, we propose three models to summarize this kind of data streams, which are the batch model, the Evolving Objects (EO) model and the Dynamic Data Stream (DDS) model. Through creating, updating and deleting user profiles, these models summarize the behaviors of each user as a profile object. Based upon these models, clustering algorithms are employed to discover interesting user groups from the profile objects. We have evaluated all the proposed models on a large real-world data set, showing that the DDS model summarizes the data streams with evolving tuples more efficiently and effectively, and provides better basis for clustering users than the other two models. © 2012 IEEE.

  12. Modeling and clustering users with evolving profiles in usage streams

    KAUST Repository

    Zhang, Chongsheng; Masseglia, Florent; Zhang, Xiangliang

    2012-01-01

    Today, there is an increasing need of data stream mining technology to discover important patterns on the fly. Existing data stream models and algorithms commonly assume that users' records or profiles in data streams will not be updated or revised once they arrive. Nevertheless, in various applications such asWeb usage, the records/profiles of the users can evolve along time. This kind of streaming data evolves in two forms, the streaming of tuples or transactions as in the case of traditional data streams, and more importantly, the evolving of user records/profiles inside the streams. Such data streams bring difficulties on modeling and clustering for exploring users' behaviors. In this paper, we propose three models to summarize this kind of data streams, which are the batch model, the Evolving Objects (EO) model and the Dynamic Data Stream (DDS) model. Through creating, updating and deleting user profiles, these models summarize the behaviors of each user as a profile object. Based upon these models, clustering algorithms are employed to discover interesting user groups from the profile objects. We have evaluated all the proposed models on a large real-world data set, showing that the DDS model summarizes the data streams with evolving tuples more efficiently and effectively, and provides better basis for clustering users than the other two models. © 2012 IEEE.

  13. Endometrial regeneration using autologous adult stem cells followed by conception by in vitro fertilization in a patient of severe Asherman′s syndrome

    Directory of Open Access Journals (Sweden)

    Chaitanya B Nagori

    2011-01-01

    Full Text Available In a woman with severe Asherman′s syndrome, curettage followed by placement of intrauterine contraceptive device (IUCD (IUCD with cyclical hormonal therapy was tried for 6 months, for development of the endometrium. When this failed, autologous stem cells were tried as an alternative therapy. From adult autologous stem cells isolated from patient′s own bone marrow, endometrial angiogenic stem cells were separated using immunomagnetic isolation. These cells were placed in the endometrial cavity under ultrasound guidance after curettage. Patient was then given cyclical hormonal therapy. Endometrium was assessed intermittently on ultrasound. On development of endometrium with a thickness of 8 mm and good vascularity, in vitro fertilization and embryo transfer was done. This resulted in positive biochemical pregnancy followed by confirmation of gestational sac, yolk sac, and embryonic pole with cardiac activity on ultrasound. Endometrial angiogenic stem cells isolated from autologous adult stem cells could regenerate injured endometrium not responding to conventional treatment for Asherman′s syndrome.

  14. Toward a Concept of Stretch Coupling in Smooth Muscle: A Thesis by Lars Thuneberg on Contractile Activity in Neonatal Interstitial Cells of Cajal

    DEFF Research Database (Denmark)

    Huizinga, Jan D; Lammers, Wim J E P; Mikkelsen, Hanne B

    2010-01-01

    The hypothesis was put forward by Thuneberg that rhythmically contracting interstitial cells of Cajal (ICC) were sensing stretch of the musculature and that this information was transmitted to smooth muscle cells via peg and socket contacts. The present study provides the evidence for the contrac......The hypothesis was put forward by Thuneberg that rhythmically contracting interstitial cells of Cajal (ICC) were sensing stretch of the musculature and that this information was transmitted to smooth muscle cells via peg and socket contacts. The present study provides the evidence...

  15. LOCAL IMMUNITY BY TISSUE-RESIDENT CD8+ MEMORY T CELLS

    Directory of Open Access Journals (Sweden)

    Thomas eGebhardt

    2012-11-01

    Full Text Available Microbial infection primes a CD8+ cytotoxic T cell response that gives rise to a long-lived population of circulating memory cells able to provide protection against systemic reinfection. Despite this, effective CD8+ T cell surveillance of barrier tissues such as skin and mucosa typically wanes with time, resulting in limited T cell-mediated protection in these peripheral tissues. However, recent evidence suggests that a specialized subset of CD103+ memory T cells can permanently lodge and persist in peripheral tissues, and that these cells can compensate for the loss of peripheral immune surveillance by circulating memory T cells. Here, we review evolving concepts regarding the generation and long-term persistence of these tissue-resident memory T cells (TRM in epithelial and neuronal tissues. We further discuss the role of TRM cells in local infection control and their contribution to localized immune phenomena, in both mice and humans.

  16. FY1995 evolvable hardware chip; 1995 nendo shinkasuru hardware chip

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-03-01

    This project aims at the development of 'Evolvable Hardware' (EHW) which can adapt its hardware structure to the environment to attain better hardware performance, under the control of genetic algorithms. EHW is a key technology to explore the new application area requiring real-time performance and on-line adaptation. 1. Development of EHW-LSI for function level hardware evolution, which includes 15 DSPs in one chip. 2. Application of the EHW to the practical industrial applications such as data compression, ATM control, digital mobile communication. 3. Two patents : (1) the architecture and the processing method for programmable EHW-LSI. (2) The method of data compression for loss-less data, using EHW. 4. The first international conference for evolvable hardware was held by authors: Intl. Conf. on Evolvable Systems (ICES96). It was determined at ICES96 that ICES will be held every two years between Japan and Europe. So the new society has been established by us. (NEDO)

  17. Qualitative Functional Decomposition Analysis of Evolved Neuromorphic Flight Controllers

    Directory of Open Access Journals (Sweden)

    Sanjay K. Boddhu

    2012-01-01

    Full Text Available In the previous work, it was demonstrated that one can effectively employ CTRNN-EH (a neuromorphic variant of EH method methodology to evolve neuromorphic flight controllers for a flapping wing robot. This paper describes a novel frequency grouping-based analysis technique, developed to qualitatively decompose the evolved controllers into explainable functional control blocks. A summary of the previous work related to evolving flight controllers for two categories of the controller types, called autonomous and nonautonomous controllers, is provided, and the applicability of the newly developed decomposition analysis for both controller categories is demonstrated. Further, the paper concludes with appropriate discussion of ongoing work and implications for possible future work related to employing the CTRNN-EH methodology and the decomposition analysis techniques presented in this paper.

  18. Cosmic Biology How Life Could Evolve on Other Worlds

    CERN Document Server

    Irwin, Louis Neil

    2011-01-01

    It is very unlikely that little green humanoids are living on Mars. But what are the possible life forms that might exist in our Solar System and how might they have evolved? This uniquely authoritative and imaginative book on the possibilties for alien life addresses the intrinsic interest that we have about life on other worlds - reinforcing some of our assumptions and reshaping others. It introduces new possibilties that will enlarge our understanding of the issue overall, in particular the enormous range of environments and planetary conditions within which life might evolve. Cosmic Biology -discusses a broad range of possible environments where alien life might have evolved; -explains why carbon-based, water-borne life is more likely that its alternatives, but is not the only possiblity; -applies the principles of planetary science and modern biology to evolutionary scenarios on other worlds; -looks at the future fates of living systems, including those on Earth.

  19. Conceptions of Parents, Conceptions of Self, and Conceptions of God.

    Science.gov (United States)

    Buri, John R.; Mueller, Rebecca A.

    Different theorists have suggested that an individual's view of God may be related to one's view of one's father, one's mother, or one's self. A study was conducted to examine the relationship of college students' conceptions of the wrathfulness-kindliness of God to their conceptions of their father's and mother's permissiveness, authoritarianism,…

  20. A decade of molecular cell biology: achievements and challenges.

    Science.gov (United States)

    Akhtar, Asifa; Fuchs, Elaine; Mitchison, Tim; Shaw, Reuben J; St Johnston, Daniel; Strasser, Andreas; Taylor, Susan; Walczak, Claire; Zerial, Marino

    2011-09-23

    Nature Reviews Molecular Cell Biology celebrated its 10-year anniversary during this past year with a series of specially commissioned articles. To complement this, here we have asked researchers from across the field for their insights into how molecular cell biology research has evolved during this past decade, the key concepts that have emerged and the most promising interfaces that have developed. Their comments highlight the broad impact that particular advances have had, some of the basic understanding that we still require, and the collaborative approaches that will be essential for driving the field forward.

  1. Design of an hybrid source with fuel cell and super-capacitors; Conception d'une source hybride utilisant une pile a combustible et des supercondensateurs

    Energy Technology Data Exchange (ETDEWEB)

    Thounthong, Ph

    2005-12-15

    The design and testing of a purely super-capacitor energy storage device as auxiliary power source in electrical vehicle applications having a PEM fuel cell as main source are presented. The two control strategies are explained. The control algorithms are that fuel cell is simply operating in almost steady state conditions in order to lessen the mechanical stresses of fuel cell and to ensure a good synchronization between fuel flow and fuel cell current. Super-capacitors are functioning during absence of energy from fuel cell, transient energy delivery or transient energy recovery. The system utilizes two modules of SAFT super-capacitive storage device. This device is connected to a 42 V DC bus by a 2-quadrant dc/dc converter, and fuel cell is connected to the dc bus by a boost converter. The system structure is realized by analogical current loops and digital control (dSPACE) for voltage loops and estimation algorithms. Experimental results with a 500 W PEM fuel cell point out the slow dynamics naturally of fuel cell because of thermodynamic and mechanical operation, and also substantiate that the super-capacitors can improve dynamics and power conditioning for automotive electrical system. (author)

  2. Design of an hybrid source with fuel cell and super-capacitors; Conception d'une source hybride utilisant une pile a combustible et des supercondensateurs

    Energy Technology Data Exchange (ETDEWEB)

    Thounthong, Ph.

    2005-12-15

    The design and testing of a purely super-capacitor energy storage device as auxiliary power source in electrical vehicle applications having a PEM fuel cell as main source are presented. The two control strategies are explained. The control algorithms are that fuel cell is simply operating in almost steady state conditions in order to lessen the mechanical stresses of fuel cell and to ensure a good synchronization between fuel flow and fuel cell current. Super-capacitors are functioning during absence of energy from fuel cell, transient energy delivery or transient energy recovery. The system utilizes two modules of SAFT super-capacitive storage device. This device is connected to a 42 V DC bus by a 2-quadrant dc/dc converter, and fuel cell is connected to the dc bus by a boost converter. The system structure is realized by analogical current loops and digital control (dSPACE) for voltage loops and estimation algorithms. Experimental results with a 500 W PEM fuel cell point out the slow dynamics naturally of fuel cell because of thermodynamic and mechanical operation, and also substantiate that the super-capacitors can improve dynamics and power conditioning for automotive electrical system. (author)

  3. Concepts, problems and the role of modifying agents in the relationship between recovery of cells' survival ability and mechanisms of repair of radiation lesions

    International Nuclear Information System (INIS)

    Orr, J.S.

    1984-01-01

    The two strands of the problem are the shapes and changes with time of cell survival curves on the one hand and the responses of cell constituents to radiation on the other. Evidence of correlations between results of studies of these two types of phenomena under the influence of a wide range of modifying agents is required to establish mechanisms. Recovery may be defined as referring to the whole cell, while repair should be regarded as a process carried out by one substance on another. The degrees of usefulness and possible deficiencies of a multi-hit/target model and a repair model for explaining cell survival curves and cell recovery are compared in a range of circumstances. A fully satisfactory model is not yet available. (author)

  4. A method of evolving novel feature extraction algorithms for detecting buried objects in FLIR imagery using genetic programming

    Science.gov (United States)

    Paino, A.; Keller, J.; Popescu, M.; Stone, K.

    2014-06-01

    In this paper we present an approach that uses Genetic Programming (GP) to evolve novel feature extraction algorithms for greyscale images. Our motivation is to create an automated method of building new feature extraction algorithms for images that are competitive with commonly used human-engineered features, such as Local Binary Pattern (LBP) and Histogram of Oriented Gradients (HOG). The evolved feature extraction algorithms are functions defined over the image space, and each produces a real-valued feature vector of variable length. Each evolved feature extractor breaks up the given image into a set of cells centered on every pixel, performs evolved operations on each cell, and then combines the results of those operations for every cell using an evolved operator. Using this method, the algorithm is flexible enough to reproduce both LBP and HOG features. The dataset we use to train and test our approach consists of a large number of pre-segmented image "chips" taken from a Forward Looking Infrared Imagery (FLIR) camera mounted on the hood of a moving vehicle. The goal is to classify each image chip as either containing or not containing a buried object. To this end, we define the fitness of a candidate solution as the cross-fold validation accuracy of the features generated by said candidate solution when used in conjunction with a Support Vector Machine (SVM) classifier. In order to validate our approach, we compare the classification accuracy of an SVM trained using our evolved features with the accuracy of an SVM trained using mainstream feature extraction algorithms, including LBP and HOG.

  5. Controversies and Evolving New Mechanisms in Subarachnoid Hemorrhage

    Science.gov (United States)

    Chen, Sheng; Feng, Hua; Sherchan, Prativa; Klebe, Damon; Zhao, Gang; Sun, Xiaochuan; Zhang, Jianmin; Tang, Jiping; Zhang, John H.

    2013-01-01

    Despite decades of study, subarachnoid hemorrhage (SAH) continues to be a serious and significant health problem in the United States and worldwide. The mechanisms contributing to brain injury after SAH remain unclear. Traditionally, most in vivo research has heavily emphasized the basic mechanisms of SAH over the pathophysiological or morphological changes of delayed cerebral vasospasm after SAH. Unfortunately, the results of clinical trials based on this premise have mostly been disappointing, implicating some other pathophysiological factors, independent of vasospasm, as contributors to poor clinical outcomes. Delayed cerebral vasospasm is no longer the only culprit. In this review, we summarize recent data from both experimental and clinical studies of SAH and discuss the vast array of physiological dysfunctions following SAH that ultimately lead to cell death. Based on the progress in neurobiological understanding of SAH, the terms “early brain injury” and “delayed brain injury” are used according to the temporal progression of SAH-induced brain injury. Additionally, a new concept of the vasculo-neuronal-glia triad model for SAH study is highlighted and presents the challenges and opportunities of this model for future SAH applications. PMID:24076160

  6. The Pan-European Reference Grid Developed in the ELECTRA Project for Deriving Innovative Observability Concepts in the Web-of-Cells Framework

    DEFF Research Database (Denmark)

    Marinelli, Mattia; Pertl, Michael; Rezkalla, Michel M.N.

    2016-01-01

    In the ELECTRA EU project, an innovative approach for frequency and voltage control is investigated, with reference to future power system scenarios characterized by massive amounts of distributed energy resources. A control architecture based on dividing the power system into a web of subsystems...... at system-wide scale. The methodology proposed in the task analyzes the system performance by investigating typical phenomena peculiar to each stability type and by developing observables necessary for the novel Web-of-Cells based control methods to operate properly at cell- and inter-cell level. Crucial...

  7. Recognizing lexical and semantic change patterns in evolving life science ontologies to inform mapping adaptation.

    Science.gov (United States)

    Dos Reis, Julio Cesar; Dinh, Duy; Da Silveira, Marcos; Pruski, Cédric; Reynaud-Delaître, Chantal

    2015-03-01

    Mappings established between life science ontologies require significant efforts to maintain them up to date due to the size and frequent evolution of these ontologies. In consequence, automatic methods for applying modifications on mappings are highly demanded. The accuracy of such methods relies on the available description about the evolution of ontologies, especially regarding concepts involved in mappings. However, from one ontology version to another, a further understanding of ontology changes relevant for supporting mapping adaptation is typically lacking. This research work defines a set of change patterns at the level of concept attributes, and proposes original methods to automatically recognize instances of these patterns based on the similarity between attributes denoting the evolving concepts. This investigation evaluates the benefits of the proposed methods and the influence of the recognized change patterns to select the strategies for mapping adaptation. The summary of the findings is as follows: (1) the Precision (>60%) and Recall (>35%) achieved by comparing manually identified change patterns with the automatic ones; (2) a set of potential impact of recognized change patterns on the way mappings is adapted. We found that the detected correlations cover ∼66% of the mapping adaptation actions with a positive impact; and (3) the influence of the similarity coefficient calculated between concept attributes on the performance of the recognition algorithms. The experimental evaluations conducted with real life science ontologies showed the effectiveness of our approach to accurately characterize ontology evolution at the level of concept attributes. This investigation confirmed the relevance of the proposed change patterns to support decisions on mapping adaptation. Copyright © 2014 Elsevier B.V. All rights reserved.

  8. Species concept and speciation

    Directory of Open Access Journals (Sweden)

    Amal Y. Aldhebiani

    2018-03-01

    Full Text Available Defining and recognizing a species has been a controversial issue for a long time. To determine the variation and the limitation between species, many concepts have been proposed. When a taxonomist study a particular taxa, he/she must adopted a species concept and provide a species limitation to define this taxa. In this paper some of species concepts are discussed starting from the typological species concepts to the phylogenetic concept. Positive and negative aspects of these concepts are represented in addition to their application. Keywords: Species concept, Species limitation, Species, Taxonomy, Classification

  9. Behaviour of and mass transfer at gas-evolving electrodes

    NARCIS (Netherlands)

    Janssen, L.J.J.

    1989-01-01

    A completes set of models for the mass transfer of indicator ions to gas-evolving electrodes with different behaviour of bubbles is described theoretically. Sliding bubbles, rising detached single bubbles, jumping detached coalescence bubbles and ensembles of these types of bubbles are taken into

  10. Analysis of Lamarckian Evolution in Morphologically Evolving Robots

    NARCIS (Netherlands)

    Jelisavcic, Milan; Kiesel, Rafael; Glette, Kyrre; Haasdijk, Evert; Eiben, A.E.

    Evolving robot morphologies implies the need for lifetime learning so that newborn robots can learn to manipulate their bodies. An individual’s morphology will obviously combine traits of all its parents; it must adapt its own controller to suit its morphology, and cannot rely on the controller of

  11. Evolving fuzzy rules for relaxed-criteria negotiation.

    Science.gov (United States)

    Sim, Kwang Mong

    2008-12-01

    In the literature on automated negotiation, very few negotiation agents are designed with the flexibility to slightly relax their negotiation criteria to reach a consensus more rapidly and with more certainty. Furthermore, these relaxed-criteria negotiation agents were not equipped with the ability to enhance their performance by learning and evolving their relaxed-criteria negotiation rules. The impetus of this work is designing market-driven negotiation agents (MDAs) that not only have the flexibility of relaxing bargaining criteria using fuzzy rules, but can also evolve their structures by learning new relaxed-criteria fuzzy rules to improve their negotiation outcomes as they participate in negotiations in more e-markets. To this end, an evolutionary algorithm for adapting and evolving relaxed-criteria fuzzy rules was developed. Implementing the idea in a testbed, two kinds of experiments for evaluating and comparing EvEMDAs (MDAs with relaxed-criteria rules that are evolved using the evolutionary algorithm) and EMDAs (MDAs with relaxed-criteria rules that are manually constructed) were carried out through stochastic simulations. Empirical results show that: 1) EvEMDAs generally outperformed EMDAs in different types of e-markets and 2) the negotiation outcomes of EvEMDAs generally improved as they negotiated in more e-markets.

  12. Friends Drinking Together: Young Adults' Evolving Support Practices

    Science.gov (United States)

    Dresler, Emma; Anderson, Margaret

    2018-01-01

    Purpose: Young adult's drinking is about pleasure, a communal practice of socialising together in a friendship group. The purpose of this paper is to investigate the evolving support practices of drinking groups for better targeting of health communications messages. Design/methodology/approach: This qualitative descriptive study examined the…

  13. Heritage – A Conceptually Evolving and Dissonant Phenomenon ...

    African Journals Online (AJOL)

    I therefore, drawing from literature and experiences gained during field observations and focus group interviews, came up with the idea of working with three viewpoints of heritage. Drawing on real life cases I argue that current heritage management and education practices' failure to recognise and respect the evolving, ...

  14. A Conceptual Framework for Evolving, Recommender Online Learning Systems

    Science.gov (United States)

    Peiris, K. Dharini Amitha; Gallupe, R. Brent

    2012-01-01

    A comprehensive conceptual framework is developed and described for evolving recommender-driven online learning systems (ROLS). This framework describes how such systems can support students, course authors, course instructors, systems administrators, and policy makers in developing and using these ROLS. The design science information systems…

  15. Evolving intelligent vehicle control using multi-objective NEAT

    NARCIS (Netherlands)

    Willigen, W.H. van; Haasdijk, E.; Kester, L.J.H.M.

    2013-01-01

    The research in this paper is inspired by a vision of intelligent vehicles that autonomously move along motorways: they join and leave trains of vehicles (platoons), overtake other vehicles, etc. We propose a multi-objective algorithm based on NEAT and SPEA2 that evolves controllers for such

  16. Hormonal evaluation of the infertile male: has it evolved?

    Science.gov (United States)

    Sussman, Ernest M; Chudnovsky, Aleksander; Niederberger, Craig S

    2008-05-01

    An endocrinologic evaluation of patients who have male-factor infertility has clearly evolved and leads to specific diagnoses and treatment strategies in a large population of infertile men. A well-considered endocrine evaluation is especially essential with the ever-growing popularity of assisted reproductive techniques and continued refinements with intracytoplasmic sperm injection.

  17. Regional and Inter-Regional Effects in Evolving Climate Networks

    Czech Academy of Sciences Publication Activity Database

    Hlinka, Jaroslav; Hartman, David; Jajcay, Nikola; Vejmelka, Martin; Donner, R.; Marwan, N.; Kurths, J.; Paluš, Milan

    2014-01-01

    Roč. 21, č. 2 (2014), s. 451-462 ISSN 1023-5809 R&D Projects: GA ČR GCP103/11/J068 Institutional support: RVO:67985807 Keywords : climate networks * evolving networks * principal component analysis * network connectivity * El Nino Subject RIV: BB - Applied Statistics, Operational Research Impact factor: 0.987, year: 2014

  18. Multivariate Epi-splines and Evolving Function Identification Problems

    Science.gov (United States)

    2015-04-15

    such extrinsic information as well as observed function and subgradient values often evolve in applications, we establish conditions under which the...previous study [30] dealt with compact intervals of IR. Splines are intimately tied to optimization problems through their variational theory pioneered...approxima- tion. Motivated by applications in curve fitting, regression, probability density estimation, variogram computation, financial curve construction

  19. Adapting Morphology to Multiple Tasks in Evolved Virtual Creatures

    DEFF Research Database (Denmark)

    Lessin, Dan; Fussell, Don; Miikkulainen, Risto

    2014-01-01

    The ESP method for evolving virtual creatures (Lessin et al., 2013) consisted of an encapsulation mechanism to preserve learned skills, a human-designed syllabus to build higherlevel skills by combining lower-level skills systematically, and a pandemonium mechanism to resolve conflicts between...

  20. Exploring the Evolving Professional Identity of Novice School Counselors

    Science.gov (United States)

    Bamgbose, Olamojiba Omolara

    2017-01-01

    The study employed a grounded theory approach to explore the evolving professional identity of novice school counselors. Participants, who are currently employed as school counselors at the elementary, middle, or high school level with 1-4 years' experience, were career changers from other helping professions and graduates from an intensive school…

  1. Evaluation and testing methodology for evolving entertainment systems

    NARCIS (Netherlands)

    Jurgelionis, A.; Bellotti, F.; IJsselsteijn, W.A.; Kort, de Y.A.W.; Bernhaupt, R.; Tscheligi, M.

    2007-01-01

    This paper presents a testing and evaluation methodology for evolving pervasive gaming and multimedia systems. We introduce the Games@Large system, a complex gaming and multimedia architecture comprised of a multitude of elements: heterogeneous end user devices, wireless and wired network

  2. Degree distribution of a new model for evolving networks

    Indian Academy of Sciences (India)

    on intuitive but realistic consideration that nodes are added to the network with both preferential and random attachments. The degree distribution of the model is between a power-law and an exponential decay. Motivated by the features of network evolution, we introduce a new model of evolving networks, incorporating the ...

  3. Evolving Nature of Sexual Orientation and Gender Identity

    Science.gov (United States)

    Jourian, T. J.

    2015-01-01

    This chapter discusses the historical and evolving terminology, constructs, and ideologies that inform the language used by those who are lesbian, gay, bisexual, and same-gender loving, who may identify as queer, as well as those who are members of trans* communities from multiple and intersectional perspectives.

  4. The Evolving Military Learner Population: A Review of the Literature

    Science.gov (United States)

    Ford, Kate; Vignare, Karen

    2015-01-01

    This literature review examines the evolving online military learner population with emphasis on current generation military learners, who are most frequently Post-9/11 veterans. The review synthesizes recent scholarly and grey literature on military learner demographics and attributes, college experiences, and academic outcomes against a backdrop…

  5. The evolving role of governments in the nuclear energy field

    International Nuclear Information System (INIS)

    Anon.

    2004-01-01

    The NEA Nuclear Development Committee (NDC) recently completed a study that looks into the evolving role of governments in nuclear energy matters. Many decisions on government intervention in recent decades have been based on the earlier experience of what works best. The report suggests some considerations that all governments could take into account when establishing their respective roles. (author)

  6. Evolving information systems: meeting the ever-changing environment

    NARCIS (Netherlands)

    Oei, J.L.H.; Proper, H.A.; Falkenberg, E.D.

    1994-01-01

    To meet the demands of organizations and their ever-changing environment, information systems are required which are able to evolve to the same extent as organizations do. Such a system has to support changes in all time-and application-dependent aspects. In this paper, requirements and a conceptual

  7. You 3.0: The Most Important Evolving Technology

    Science.gov (United States)

    Tamarkin, Molly; Bantz, David A.; Childs, Melody; diFilipo, Stephen; Landry, Stephen G.; LoPresti, Frances; McDonald, Robert H.; McGuthry, John W.; Meier, Tina; Rodrigo, Rochelle; Sparrow, Jennifer; Diggs, D. Teddy; Yang, Catherine W.

    2010-01-01

    That technology evolves is a given. Not as well understood is the impact of technological evolution on each individual--on oneself, one's skill development, one's career, and one's relationship with the work community. The authors believe that everyone in higher education will become an IT worker and that IT workers will be managing a growing…

  8. Sextant: Visualizing time-evolving linked geospatial data

    NARCIS (Netherlands)

    C. Nikolaou (Charalampos); K. Dogani (Kallirroi); K. Bereta (Konstantina); G. Garbis (George); M. Karpathiotakis (Manos); K. Kyzirakos (Konstantinos); M. Koubarakis (Manolis)

    2015-01-01

    textabstractThe linked open data cloud is constantly evolving as datasets get continuously updated with newer versions. As a result, representing, querying, and visualizing the temporal dimension of linked data is crucial. This is especially important for geospatial datasets that form the backbone

  9. Adaptive Framework for Classification and Novel Class Detection over Evolving Data Streams with Limited Labeled Data.

    Energy Technology Data Exchange (ETDEWEB)

    Haque, Ahsanul [Univ. of Texas, Dallas, TX (United States); Khan, Latifur [Univ. of Texas, Dallas, TX (United States); Baron, Michael [Univ. of Texas, Dallas, TX (United States); Ingram, Joey Burton [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    Most approaches to classifying evolving data streams either divide the stream of data into fixed-size chunks or use gradual forgetting to address the problems of infinite length and concept drift. Finding the fixed size of the chunks or choosing a forgetting rate without prior knowledge about time-scale of change is not a trivial task. As a result, these approaches suffer from a trade-off between performance and sensitivity. To address this problem, we present a framework which uses change detection techniques on the classifier performance to determine chunk boundaries dynamically. Though this framework exhibits good performance, it is heavily dependent on the availability of true labels of data instances. However, labeled data instances are scarce in realistic settings and not readily available. Therefore, we present a second framework which is unsupervised in nature, and exploits change detection on classifier confidence values to determine chunk boundaries dynamically. In this way, it avoids the use of labeled data while still addressing the problems of infinite length and concept drift. Moreover, both of our proposed frameworks address the concept evolution problem by detecting outliers having similar values for the attributes. We provide theoretical proof that our change detection method works better than other state-of-the-art approaches in this particular scenario. Results from experiments on various benchmark and synthetic data sets also show the efficiency of our proposed frameworks.

  10. Evolvable mathematical models: A new artificial Intelligence paradigm

    Science.gov (United States)

    Grouchy, Paul

    We develop a novel Artificial Intelligence paradigm to generate autonomously artificial agents as mathematical models of behaviour. Agent/environment inputs are mapped to agent outputs via equation trees which are evolved in a manner similar to Symbolic Regression in Genetic Programming. Equations are comprised of only the four basic mathematical operators, addition, subtraction, multiplication and division, as well as input and output variables and constants. From these operations, equations can be constructed that approximate any analytic function. These Evolvable Mathematical Models (EMMs) are tested and compared to their Artificial Neural Network (ANN) counterparts on two benchmarking tasks: the double-pole balancing without velocity information benchmark and the challenging discrete Double-T Maze experiments with homing. The results from these experiments show that EMMs are capable of solving tasks typically solved by ANNs, and that they have the ability to produce agents that demonstrate learning behaviours. To further explore the capabilities of EMMs, as well as to investigate the evolutionary origins of communication, we develop NoiseWorld, an Artificial Life simulation in which interagent communication emerges and evolves from initially noncommunicating EMM-based agents. Agents develop the capability to transmit their x and y position information over a one-dimensional channel via a complex, dialogue-based communication scheme. These evolved communication schemes are analyzed and their evolutionary trajectories examined, yielding significant insight into the emergence and subsequent evolution of cooperative communication. Evolved agents from NoiseWorld are successfully transferred onto physical robots, demonstrating the transferability of EMM-based AIs from simulation into physical reality.

  11. CELL PHONE ADDICTION: A REVIEW

    Directory of Open Access Journals (Sweden)

    JOSE DE SOLA

    2016-10-01

    Full Text Available We present a review of the studies that have been published about addiction to cell phones. We analyse the concept of cell phone addiction as well as its prevalence, study methodologies, psychological features and associated psychiatric comorbidities. Research in this field has generally evolved from a global view of the cell phone as a device to its analysis via applications and contents. The diversity of criteria and methodological approaches that have been used is notable, as is a certain lack of conceptual delimitation that has resulted in a broad spread of prevalent data. There is a consensus about the existence of cell phone addiction, but the delimitation and criteria used by various researchers vary. Cell phone addiction shows a distinct user profile that differentiates it from Internet addiction. Without evidence pointing to the influence of cultural level and socioeconomic status, the pattern of abuse is greatest among young people, primarily females. Intercultural and geographical differences have not been sufficiently studied. The problematic use of cell phones has been associated with personality variables such as extraversion, neuroticism, self-esteem, impulsivity, self-identity and self-image. Similarly, sleep disturbance, anxiety, stress, and, to a lesser extent, depression, which are also associated with Internet abuse, have been associated with problematic cell phone use. In addition, the present review reveals the coexistence relationship between problematic cell phone use and substance use such as tobacco and alcohol.

  12. The actual current density of gas-evolving electrodes—Notes on the bubble coverage

    International Nuclear Information System (INIS)

    Vogt, H.

    2012-01-01

    All investigations of electrochemical reactors with gas-evolving electrodes must take account of the fact that the actual current density controlling cell operation commonly differs substantially from the nominal current density used for practical purposes. Both quantities are interrelated by the fractional bubble coverage. This parameter is shown to be affected by a large number of operational quantities. However, available relationships of the bubble coverage take account only of the nominal current density. A further essential insufficiency is their inconsistency with reality for very large values of the bubble coverage being of relevance for operation conditions leading to anode effects. An improved relationship applicable to the total range is proposed.

  13. Development of Hematopoietic Stem Cell Based Gene Therapy for HIV-1 Infection: Considerations for Proof of Concept Studies and Translation to Standard Medical Practice

    Directory of Open Access Journals (Sweden)

    David L. DiGiusto

    2013-11-01

    Full Text Available Over the past 15 years we have been investigating an alternative approach to treating HIV-1/AIDS, based on the creation of a disease-resistant immune system through transplantation of autologous, gene-modified (HIV-1-resistant hematopoietic stem and progenitor cells (GM-HSPC. We propose that the expression of selected RNA-based HIV-1 inhibitors in the CD4+ cells derived from GM-HSPC will protect them from HIV-1 infection and results in a sufficient immune repertoire to control HIV-1 viremia resulting in a functional cure for HIV-1/AIDS. Additionally, it is possible that the subset of protected T cells will also be able to facilitate the immune-based elimination of latently infected cells if they can be activated to express viral antigens. Thus, a single dose of disease resistant GM-HSPC could provide an effective treatment for HIV-1+ patients who require (or desire an alternative to lifelong antiretroviral chemotherapy. We describe herein the results from several pilot clinical studies in HIV-1 patients and our strategies to develop second generation vectors and clinical strategies for HIV-1+ patients with malignancy who require ablative chemotherapy as part of treatment and others without malignancy. The important issues related to stem cell source, patient selection, conditioning regimen and post-infusion correlative studies become increasingly complex and are discussed herein.

  14. The transpiration cooled first wall and blanket concept

    International Nuclear Information System (INIS)

    Barleon, Leopold; Wong, Clement

    2002-01-01

    To achieve high thermal performance at high power density the EVOLVE concept was investigated under the APEX program. The EVOLVE W-alloy first wall and blanket concept proposes to use transpiration cooling of the first wall and boiling or vaporizing lithium (Li) in the blanket zone. Critical issues of this concept are: the Magnetohydrodynamic (MHD) pressure losses of the Li circuit, the evaporation through a capillary structure and the needed superheating of the Li at the first wall and blanket zones. Application of the transpiration concept to the blanket region results in the integrated transpiration cooling concept (ITCC) with either toroidal or poloidal first wall channels. For both orientations the routing of the liquid Li and the Li vapor has been modeled and the corresponding pressure losses have been calculated by varying the width of the supplying slot and the capillary diameter. The concept works when the sum of the active and passive pumping head is higher than the total system pressure losses and when the temperature at the inner side of the first wall does not override the superheating limit of the coolant. This cooling concept has been extended to the divertor design, and the removal of a surface heat flux of up to 10 MW/m 2 appears to be possible, but this paper will focus on the transpiration cooled first wall and blanket concept assessment

  15. Subtype assignment of CLL based on B-cell subset associated gene signatures from normal bone marrow – A proof of concept study

    DEFF Research Database (Denmark)

    Nørgaard, Caroline Holm; Jakobsen, Lasse Hjort; Gentles, Andrew J.

    2018-01-01

    . Our hypothesis is that by segregating CLL according to BAGS, we can identify subtypes with prognostic implications in support of pathogenetic value of BAGS. Microarray-based gene-expression samples from eight independent CLL cohorts (1,024 untreated patients) were BAGS-stratified into pre-BI, pre...... subtype resistance towards rituximab and cyclophosphamide varied for rituximab, whereas all subtypes were sensitive to cyclophosphamide. This study supports our hypothesis that BAGS-subtyping may be of tangible prognostic and pathogenetic value for CLL patients.......Diagnostic and prognostic evaluation of chronic lymphocytic leukemia (CLL) involves blood cell counts, immunophenotyping, IgVH mutation status, and cytogenetic analyses. We generated B-cell associated gene-signatures (BAGS) based on six naturally occurring B-cell subsets within normal bone marrow...

  16. Frequency-Domain Tomography for Single-shot, Ultrafast Imaging of Evolving Laser-Plasma Accelerators

    Science.gov (United States)

    Li, Zhengyan; Zgadzaj, Rafal; Wang, Xiaoming; Downer, Michael

    2011-10-01

    Intense laser pulses propagating through plasma create plasma wakefields that often evolve significantly, e.g. by expanding and contracting. However, such dynamics are known in detail only through intensive simulations. Laboratory visualization of evolving plasma wakes in the ``bubble'' regime is important for optimizing and scaling laser-plasma accelerators. Recently snap-shots of quasi-static wakes were recorded using frequency-domain holography (FDH). To visualize the wake's evolution, we have generalized FDH to frequency-domain tomography (FDT), which uses multiple probes propagating at different angles with respect to the pump pulse. Each probe records a phase streak, imprinting a partial record of the evolution of pump-created structures. We then topographically reconstruct the full evolution from all phase streaks. To prove the concept, a prototype experiment visualizing nonlinear index evolution in glass is demonstrated. Four probes propagating at 0, 0.6, 2, 14 degrees to the index ``bubble'' are angularly and temporally multiplexed to a single spectrometer to achieve cost-effective FDT. From these four phase streaks, an FDT algorithm analogous to conventional CT yields a single-shot movie of the pump's self-focusing dynamics.

  17. The evolving universe and the origin of life the search for our cosmic roots

    CERN Document Server

    Teerikorpi, Pekka; Lehto, Harry; Chernin, Arthur; Byrd, Gene; Lehto, K

    2008-01-01

    Sir Isaac Newton famously said, regarding his discoveries, "If I have seen further it is by standing upon the shoulders of giants." The Evolving Universe and the Origin of Life describes, complete with fascinating biographical details of the thinkers involved, the ascent to the metaphorical shoulders accomplished by the greatest minds in history. For the first time, a single book can take the reader on a journey through the history of the universe as interpreted by the expanding body of knowledge of humankind. From subatomic particles to the protein chains that form life, and expanding in scale to the entire universe, this book covers the science that explains how we came to be. The Evolving Universe and the Origin of Life contains a great breadth of knowledge, from astronomy to physics, from chemistry to biology. It includes over 350 figures that enhance the comprehension of concepts both basic and advanced, and is a non-technical, easy-to-read text at an introductory college level that is ideal for anyone i...

  18. Evolving Role of the Power Sector Regulator: A Clean Energy Regulators Initiative Report

    Energy Technology Data Exchange (ETDEWEB)

    Zinaman, O.; Miller, M.; Bazilian, M.

    2014-04-01

    This paper seeks to briefly characterize the evolving role of power sector regulation. Given current global dynamics, regulation of the power sector is undergoing dramatic changes. This transformation is being driven by various factors including technological advances and cost reductions in renewable energy, energy efficiency, and demand management; increasing air pollution and climate change concerns; and persistent pressure for ensuring sustainable economic development and increased access to energy services by the poor. These issues add to the already complex task of power sector regulation, of which the fundamental remit remains to objectively and transparently ensure least-cost service delivery at high quality. While no single regulatory task is trivial to undertake, it is the prioritization and harmonization of a multitude of objectives that exemplifies the essential challenge of power sector regulation. Evolving regulatory roles can be understood through the concept of existing objectives and an additional layer of emerging objectives. Following this categorization, we describe seven existing objectives of power sector regulators and nine emerging objectives, highlighting key challenges and outlining interdependencies. This essay serves as a preliminary installment in the Clean Energy Regulatory Initiative (CERI) series, and aims to lay the groundwork for subsequent reports and case studies that will explore these topics in more depth.

  19. Benefits of Mars ISRU Regolith Water Processing: A Case Study for the NASA Evolvable Mars Campaign

    Science.gov (United States)

    Kleinhenz, Julie; Paz, Aaron; Mueller, Robert

    2016-01-01

    ISRU of Mars resources was baselined in 2009 Design Reference Architecture (DRA) 5.0, but only for Oxygen production using atmospheric CO2. The Methane (LCH4) needed for ascent propulsion of the Mars Ascent Vehicle (MAV) would need to be brought from Earth. However: Extracting water from the Martian Regolith enables the production of both Oxygen and Methane from Mars resources: Water resources could also be used for other applications including: Life support, radiation shielding, plant growth, etc. Water extraction was not baselined in DRA5.0 due to perceived difficulties and complexity in processing regolith. The NASA Evolvable Mars Campaign (EMC) requested studies to look at the quantitative benefits and trades of using Mars water ISRUPhase 1: Examined architecture scenarios for regolith water retrieval. Completed October 2015. Phase 2: Deep dive of one architecture concept to look at end-to-end system size, mass, power of a LCH4/LO2 ISRU production system

  20. Evolving software products, the design of a water-related modeling software ecosystem

    DEFF Research Database (Denmark)

    Manikas, Konstantinos

    2017-01-01

    more than 50 years ago. However, a radical change of software products to evolve both in the software engineering as much as the organizational and business aspects in a disruptive manner are rather rare. In this paper, we report on the transformation of one of the market leader product series in water......-related calculation and modeling from a traditional business-as-usual series of products to an evolutionary software ecosystem. We do so by relying on existing concepts on software ecosystem analysis to analyze the future ecosystem. We report and elaborate on the main focus points necessary for this transition. We...... argue for the generalization of our focus points to the transition from traditional business-as-usual software products to software ecosystems....

  1. Evolving Systems of Care with Total Clinical Outcomes Management

    Science.gov (United States)

    Lyons, John S.; Epstein, Richard A.; Jordan, Neil

    2010-01-01

    The current article proposes that further specification of the system of care concept is required. Based on the assertions that the system of care concept (a) refers to an ideal as opposed to an observable phenomenon, and (b) is engaged in offering transformational experiences, the authors propose that the system of care definition must be…

  2. The Extended Enterprise concept

    DEFF Research Database (Denmark)

    Larsen, Lars Bjørn; Vesterager, Johan; Gobbi, Chiara

    1999-01-01

    This paper provides an overview of the work that has been done regarding the Extended Enterprise concept in the Common Concept team of Globeman 21 including references to results deliverables concerning the development of the Extended Enterprise concept. The first section presents the basic concept...... picture from Globeman21, which illustrates the Globeman21 way of realising the Extended Enterprise concept. The second section presents the Globeman21 EE concept in a life cycle perspective, which to a large extent is based on the thoughts and ideas behind GERAM (ISO/DIS 15704)....

  3. Human Pluripotent Stem Cell-derived Cortical Neurons for High Throughput Medication Screening in Autism: A Proof of Concept Study in SHANK3 Haploinsufficiency Syndrome

    Directory of Open Access Journals (Sweden)

    Hélène Darville

    2016-07-01

    Full Text Available Autism spectrum disorders affect millions of individuals worldwide, but their heterogeneity complicates therapeutic intervention that is essentially symptomatic. A versatile yet relevant model to rationally screen among hundreds of therapeutic options would help improving clinical practice. Here we investigated whether neurons differentiated from pluripotent stem cells can provide such a tool using SHANK3 haploinsufficiency as a proof of principle. A library of compounds was screened for potential to increase SHANK3 mRNA content in neurons differentiated from control human embryonic stem cells. Using induced pluripotent stem cell technology, active compounds were then evaluated for efficacy in correcting dysfunctional networks of neurons differentiated from individuals with deleterious point mutations of SHANK3. Among 202 compounds tested, lithium and valproic acid showed the best efficacy at corrected SHANK3 haploinsufficiency associated phenotypes in cellulo. Lithium pharmacotherapy was subsequently provided to one patient and, after one year, an encouraging decrease in autism severity was observed. This demonstrated that pluripotent stem cell-derived neurons provide a novel cellular paradigm exploitable in the search for specific disease-modifying treatments.

  4. From Bunsen Burners to Fuel Cells: Invoking Energy Transducers to Exemplify "Paths" and Unify the Energy-Related Concepts of Thermochemistry and Thermodynamics

    Science.gov (United States)

    Hladky, Paul W.

    2009-01-01

    The conversion of chemical energy entirely into thermal energy by Bunsen burners and into thermal energy and electrical energy by fuel cells of varying efficiencies illustrates different paths by which a chemical reaction can occur. Using the efficiency of producing electrical energy as a path label allows all of the energy-related quantities to…

  5. Clustering impact regime with shocks in freely evolving granular gas

    Science.gov (United States)

    Isobe, Masaharu

    2017-06-01

    A freely cooling granular gas without any external force evolves from the initial homogeneous state to the inhomogeneous clustering state, at which the energy decay deviates from the Haff's law. The asymptotic behavior of energy in the inelastic hard sphere model have been predicted by several theories, which are based on the mode coupling theory or extension of inelastic hard rods gas. In this study, we revisited the clustering regime of freely evolving granular gas via large-scale molecular dynamics simulation with up to 16.7 million inelastic hard disks. We found novel regime regarding on collisions between "clusters" spontaneously appearing after clustering regime, which can only be identified more than a few million particles system. The volumetric dilatation pattern of semicircular shape originated from density shock propagation are well characterized on the appearing of "cluster impact" during the aggregation process of clusters.

  6. Finding evolved stars in the inner Galactic disk with Gaia

    Science.gov (United States)

    Quiroga-Nuñez, L. H.; van Langevelde, H. J.; Pihlström, Y. M.; Sjouwerman, L. O.; Brown, A. G. A.

    2018-04-01

    The Bulge Asymmetries and Dynamical Evolution (BAaDE) survey will provide positions and line-of-sight velocities of ~20, 000 evolved, maser bearing stars in the Galactic plane. Although this Galactic region is affected by optical extinction, BAaDE targets may have Gaia cross-matches, eventually providing additional stellar information. In an initial attempt to cross-match BAaDE targets with Gaia, we have found more than 5,000 candidates. Of these, we may expect half to show SiO emission, which will allow us to obtain velocity information. The cross-match is being refined to avoid false positives using different criteria based on distance analysis, flux variability, and color assessment in the mid- and near-IR. Once the cross-matches can be confirmed, we will have a unique sample to characterize the stellar population of evolved stars in the Galactic bulge, which can be considered fossils of the Milky Way formation.

  7. Self-regulating and self-evolving particle swarm optimizer

    Science.gov (United States)

    Wang, Hui-Min; Qiao, Zhao-Wei; Xia, Chang-Liang; Li, Liang-Yu

    2015-01-01

    In this article, a novel self-regulating and self-evolving particle swarm optimizer (SSPSO) is proposed. Learning from the idea of direction reversal, self-regulating behaviour is a modified position update rule for particles, according to which the algorithm improves the best position to accelerate convergence in situations where the traditional update rule does not work. Borrowing the idea of mutation from evolutionary computation, self-evolving behaviour acts on the current best particle in the swarm to prevent the algorithm from prematurely converging. The performance of SSPSO and four other improved particle swarm optimizers is numerically evaluated by unimodal, multimodal and rotated multimodal benchmark functions. The effectiveness of SSPSO in solving real-world problems is shown by the magnetic optimization of a Halbach-based permanent magnet machine. The results show that SSPSO has good convergence performance and high reliability, and is well matched to actual problems.

  8. AUTOMOTIVE APPLICATIONS OF EVOLVING TAKAGI-SUGENO-KANG FUZZY MODELS

    Directory of Open Access Journals (Sweden)

    Radu-Emil Precup

    2017-08-01

    Full Text Available This paper presents theoretical and application results concerning the development of evolving Takagi-Sugeno-Kang fuzzy models for two dynamic systems, which will be viewed as controlled processes, in the field of automotive applications. The two dynamic systems models are nonlinear dynamics of the longitudinal slip in the Anti-lock Braking Systems (ABS and the vehicle speed in vehicles with the Continuously Variable Transmission (CVT systems. The evolving Takagi-Sugeno-Kang fuzzy models are obtained as discrete-time fuzzy models by incremental online identification algorithms. The fuzzy models are validated against experimental results in the case of the ABS and the first principles simulation results in the case of the vehicle with the CVT.

  9. Design of the tool for periodic not evolvent profiles

    Directory of Open Access Journals (Sweden)

    Anisimov Roman

    2017-01-01

    Full Text Available The new approach to profiling of the tool for processing of parts with periodic not evolvent profiles are considered in the article The discriminatory analysis of periodic profiles including repetition of profile both in the plane of perpendicular axis of part, and in the plane of passing along part of axis is offered. In the basis of the offered profiling method the idea of space shaping by rated surface of product of tool surface lies. The big advantage of the offered approach in profiling is its combination with the analysis of parameters of process of engineering work. It allows to predict the accuracy and surface quality of product with not evolvent periodic profile. While using the offered approach the pinion cutter for processing of wheels with internal triangular teeths and mill for processing of the screw of the counter of consumption of liquid, complex profile of which consists of several formings, have been received

  10. Evolvability of thermophilic proteins from archaea and bacteria.

    Science.gov (United States)

    Takano, Kazufumi; Aoi, Atsushi; Koga, Yuichi; Kanaya, Shigenori

    2013-07-16

    Proteins from thermophiles possess high thermostability. The stabilization mechanisms differ between archaeal and bacterial proteins, whereby archaeal proteins are mainly stabilized via hydrophobic interactions and bacterial proteins by ion pairs. High stability is an important factor in promoting protein evolution, but the precise means by which different stabilization mechanisms affect the evolution process remain unclear. In this study, we investigated a random mutational drift of esterases from thermophilic archaea and bacteria at high temperatures. Our results indicate that mutations in archaeal proteins lead to improved function with no loss of stability, while mutant bacterial proteins are largely destabilized with decreased activity at high temperatures. On the basis of these findings, we suggest that archaeal proteins possess higher "evolvability" than bacterial proteins under temperature selection and are additionally able to evolve into eukaryotic proteins.

  11. Programming adaptive control to evolve increased metabolite production.

    Science.gov (United States)

    Chou, Howard H; Keasling, Jay D

    2013-01-01

    The complexity inherent in biological systems challenges efforts to rationally engineer novel phenotypes, especially those not amenable to high-throughput screens and selections. In nature, increased mutation rates generate diversity in a population that can lead to the evolution of new phenotypes. Here we construct an adaptive control system that increases the mutation rate in order to generate diversity in the population, and decreases the mutation rate as the concentration of a target metabolite increases. This system is called feedback-regulated evolution of phenotype (FREP), and is implemented with a sensor to gauge the concentration of a metabolite and an actuator to alter the mutation rate. To evolve certain novel traits that have no known natural sensors, we develop a framework to assemble synthetic transcription factors using metabolic enzymes and construct four different sensors that recognize isopentenyl diphosphate in bacteria and yeast. We verify FREP by evolving increased tyrosine and isoprenoid production.

  12. Evolving approaches to the ethical management of genomic data.

    Science.gov (United States)

    McEwen, Jean E; Boyer, Joy T; Sun, Kathie Y

    2013-06-01

    The ethical landscape in the field of genomics is rapidly shifting. Plummeting sequencing costs, along with ongoing advances in bioinformatics, now make it possible to generate an enormous volume of genomic data about vast numbers of people. The informational richness, complexity, and frequently uncertain meaning of these data, coupled with evolving norms surrounding the sharing of data and samples and persistent privacy concerns, have generated a range of approaches to the ethical management of genomic information. As calls increase for the expanded use of broad or even open consent, and as controversy grows about how best to handle incidental genomic findings, these approaches, informed by normative analysis and empirical data, will continue to evolve alongside the science. Published by Elsevier Ltd.

  13. Evolving Robot Controllers for Structured Environments Through Environment Decomposition

    DEFF Research Database (Denmark)

    Moreno, Rodrigo; Faiña, Andres; Støy, Kasper

    2015-01-01

    In this paper we aim to develop a controller that allows a robot to traverse an structured environment. The approach we use is to decompose the environment into simple sub-environments that we use as basis for evolving the controller. Specifically, we decompose a narrow corridor environment...... environments and that the order in which the decomposed sub-environments are presented in sequence impacts the performance of the evolutionary algorithm....

  14. The Evolving Importance of Banks and Securities Markets

    OpenAIRE

    Demirguc-Kunt, Asli; Feyen, Erik; Levine, Ross

    2011-01-01

    The roles of banks and securities markets evolve during the process of economic development. As countries develop economically, (1) the size of both banks and securities markets increases relative to the size of the economy, (2) the association between an increase in economic output and an increase in bank development becomes smaller, and (3) the association between an increase in economic output and an increase in securities market development becomes larger. These findings are consistent wi...

  15. A novel evolving scale-free model with tunable attractiveness

    International Nuclear Information System (INIS)

    Xuan, Liu; Tian-Qi, Liu; Xing-Yuan, Li; Hao, Wang

    2010-01-01

    In this paper, a new evolving model with tunable attractiveness is presented. Based on the Barabasi–Albert (BA) model, we introduce the attractiveness of node which can change with node degree. Using the mean-field theory, we obtain the analytical expression of power-law degree distribution with the exponent γ in (3, ∞). The new model is more homogeneous and has a lower clustering coefficient and bigger average path length than the BA model. (general)

  16. india's northward drift and collision with asia: evolving faunal response

    Indian Academy of Sciences (India)

    INDIA'S NORTHWARD DRIFT AND COLLISION WITH ASIA: EVOLVING FAUNAL RESPONSE · Slide 2 · Slide 3 · Slide 4 · Slide 5 · Slide 6 · Slide 7 · Slide 8 · Slide 9 · Slide 10 · Slide 11 · Slide 12 · Slide 13 · Slide 14 · Slide 15 · Slide 16 · Slide 17 · Slide 18 · Slide 19 · Slide 20 · Slide 21 · Slide 22 · Slide 23 · Slide 24.

  17. Reconstructing the Morphology of an Evolving Coronal Mass Ejection

    Science.gov (United States)

    2009-01-01

    694, 707 Wood, B. E., Howard, R. A ., Thernisien, A ., Plunkett, S. P., & Socker, D. G. 2009b, Sol. Phys., 259, 163 Wood, B. E., Karovska , M., Chen, J...Reconstructing the Morphology of an Evolving Coronal Mass Ejection B. E. Wood, R. A . Howard, D. G. Socker Naval Research Laboratory, Space Science...mission, we empirically reconstruct the time-dependent three-dimensional morphology of a coronal mass ejection (CME) from 2008 June 1, which exhibits

  18. The evolving role of information technology in internal auditing

    OpenAIRE

    2015-01-01

    M.Com. (Computer Auditing) Modern organizations are increasingly dependent on information technology (IT) for various reasons: to enhance their operational efficiency, reduce costs or even attain a competitive advantage. The role of information technology in the organization continues to evolve and this has an impact for the internal audit functions that serve these organizations. The study investigated whether the King III report, ISACA standards and IIA standards assist the internal audi...

  19. The evolving role of paramedics - a NICE problem to have?

    Science.gov (United States)

    Eaton, Georgette; Mahtani, Kamal; Catterall, Matt

    2018-07-01

    This short essay supports the growing role of paramedics in the clinical and academic workforce. We present a commentary of recent draft consultations by the National Institute for Health and Care Excellence in England that set out how the role of paramedics may be evolving to assist with the changing demands on the clinical workforce. Using these consultations as a basis, we extend their recommendations and suggest that the profession should also lead the academically driven evaluation of these new roles.

  20. A search for radio emission from exoplanets around evolved stars

    Science.gov (United States)

    O'Gorman, E.; Coughlan, C. P.; Vlemmings, W.; Varenius, E.; Sirothia, S.; Ray, T. P.; Olofsson, H.

    2018-04-01

    The majority of searches for radio emission from exoplanets have to date focused on short period planets, i.e., the so-called hot Jupiter type planets. However, these planets are likely to be tidally locked to their host stars and may not generate sufficiently strong magnetic fields to emit electron cyclotron maser emission at the low frequencies used in observations (typically ≥150 MHz). In comparison, the large mass-loss rates of evolved stars could enable exoplanets at larger orbital distances to emit detectable radio emission. Here, we first show that the large ionized mass-loss rates of certain evolved stars relative to the solar value could make them detectable with the LOw Frequency ARray (LOFAR) at 150 MHz (λ = 2 m), provided they have surface magnetic field strengths >50 G. We then report radio observations of three long period (>1 au) planets that orbit the evolved stars β Gem, ι Dra, and β UMi using LOFAR at 150 MHz. We do not detect radio emission from any system but place tight 3σ upper limits of 0.98, 0.87, and 0.57 mJy on the flux density at 150 MHz for β Gem, ι Dra, and β UMi, respectively. Despite our non-detections these stringent upper limits highlight the potential of LOFAR as a tool to search for exoplanetary radio emission at meter wavelengths.