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Sample records for prevent irreversible organ

  1. Irreversibility and self-organization in spin glasses. 2. Irreversibility and the problem of configuration averaging

    International Nuclear Information System (INIS)

    Kovrov, V.P.; Kurbatov, A.M.

    1989-05-01

    The generalization of a configuration averaging to a system displaying irreversible effects is suggested. The properties of the ''pathological'' equilibrium state at low temperatures are determined and discussed. (author). 16 refs, 3 figs

  2. Irreversible Total Loss of Brain Function and Organ Donation in Patients with Aneurysmal Subarachnoid Hemorrhage.

    Science.gov (United States)

    Mohme, Malte; Sauvigny, Thomas; Grensemann, Jörn; Söffker, Gerold; Kluge, Stefan; Westphal, Manfred; Czorlich, Patrick

    2017-09-01

    Aneurysmal subarachnoid hemorrhage (aSAH) is a life-threatening disease with an often fatal clinical course leading to irreversible loss of brain function (ILBF) (i.e., brain death). The purpose of this study was to assess the prevalence and characteristics of patients with aSAH who became organ donors after diagnosis of ILBF. Anonymized clinical data sets of 395 patients treated for aSAH at a university medical center from January 2011 to December 2016 were retrospectively analyzed. Prevalence of consent for organ donation and clinical characteristics, including parameters for diagnosis of irreversible loss of brain function, were assessed. After initial admission to the intensive care unit, 18.0% of patients (n = 71) died (Glasgow Outcome Scale score 1). Intracerebral hemorrhage occurred in 42.3% of patients who died, aneurysmal rebleeding occurred in 19.7%, and intraventricular hemorrhage occurred in 87.3%. In 50.7% of patients who died (n = 36), ILBF was diagnosed, and 32.4% (n = 23) of these patients became organ donors. In 55.6%, additional diagnostic electroencephalography was performed. Male patients significantly more often became organ donors than female patients (P = 0.008). ILBF with subsequent organ donation was predominantly seen in patients organs were explanted for donation, including 42 kidneys, 21 livers, 3 pancreas, 11 hearts and 8 lungs. ILBF in the setting of fatal aSAH is a prevalent diagnosis with complex demands for neurointensive care physicians. We demonstrated the clinical characteristics and epidemiologic factors of patients with aSAH converting to organ donors. Copyright © 2017 Elsevier Inc. All rights reserved.

  3. Early diagnosis of the urofacial syndrome is essential to prevent irreversible renal failure

    Directory of Open Access Journals (Sweden)

    Francisco A. Nicanor

    2005-10-01

    Full Text Available INTRODUCTION: The urofacial or Ochoa syndrome is a rare disease characterized by the presence of functional obstructive uropathy associated with peculiar facial features when patients attempt to smile or laugh. Unfortunately, many of these patients remain without proper diagnosis or adequate treatment due to lack of recognition of the disease. This can ultimately result in upper tract deterioration and eventual renal failure. We present our experience with this rare syndrome. MATERIALS AND METHODS: We identified 3 patients who presented initially with acute renal failure, urinary tract infection (UTI and severe dysfunctional elimination. All patients were thoroughly evaluated, including screening for spinal cord anomalies, and were subsequently diagnosed with urofacial syndrome. RESULTS: At the outset, the two older patients (aged 4 and 9 years presented with the typical facial features when attempting to smile or laugh. One patient in the newborn period presented with urinary and fecal retention and septicemia and, to our knowledge, represents the youngest case of urofacial syndrome reported so far. All patients were evaluated with ultrasonography, renal scan, voiding cystourethrogram (VCUG and urodynamics. Findings included hydronephrosis and a thick-walled, trabeculated bladder with poor compliance and detrusor hypereflexia respectively in each patient. All were subsequently treated with clean intermittent catheterization (CIC, antibiotic prophylaxis and anticholinergic therapy. One patient required appendicovesicostomy for CIC due to discomfort secondary to a sensate urethra. CONCLUSIONS: Our series demonstrates that early recognition of this rare syndrome is necessary to adequately treat and prevent upper tract deterioration in these unique individuals. Although the urofacial is difficult to diagnose in infants, cognizance must be maintained in order to prevent severe subsequent sequalae.

  4. Preventing organ damage by genetic testing for hereditary ...

    African Journals Online (AJOL)

    Haemochromatosis can be prevented by regular blood donation or phlebotomy and therefore detection of a genetic predisposition at an early age, before irreversible damage to cardiac, hepatic and endocrine tissue occurs, represents an important clinical goal. South African Family Practice Vol. 47(2) 2005: 44-45 ...

  5. Organizing knowledge for tutoring fire loss prevention

    Science.gov (United States)

    Schmoldt, Daniel L.

    1989-09-01

    The San Bernardino National Forest in southern California has recently developed a systematic approach to wildfire prevention planning. However, a comprehensive document or other mechanism for teaching this process to other prevention personnel does not exist. An intelligent tutorial expert system is being constructed to provide a means for learning the process and to assist in the creation of specific prevention plans. An intelligent tutoring system (ITS) contains two types of knowledge—domain and tutoring. The domain knowledge for wildfire prevention is structured around several foci: (1) individual concepts used in prevention planning; (2) explicitly specified interrelationships between concepts; (3) deductive methods that contain subjective judgment normally unavailable to less-experienced users; (4) analytical models of fire behavior used for identification of hazard areas; (5) how-to guidance needed for performance of planning tasks; and (6) expository information that provides a rationale for planning steps and ideas. Combining analytical, procedure, inferential, conceptual, and expositional knowledge into a tutoring environment provides the student and/or user with a multiple perspective of the subject matter. A concept network provides a unifying framework for structuring and utilizing these diverse forms of prevention planning knowledge. This network structure borrows from and combines semantic networks and frame-based knowledge representations. The flexibility of this organization facilitates an effective synthesis and organization of multiple knowledge forms.

  6. Prevention of organic iodide formation in BWR's

    International Nuclear Information System (INIS)

    Karjunen, T.; Laitinen, T.; Piippo, J.; Sirkiae, P.

    1996-01-01

    During an accident, many different forms of iodine may emerge. Organic iodides, such as methyl iodide and ethyl iodide, are relatively volatile, and thus their appearance leads to increased concentration of gaseous iodine. Since organic iodides are also relatively immune to most accident mitigation measures, such as sprays and filters, they can affect the accident source term significantly even when only a small portion of iodine is in organic form. Formation of organic iodides may not be limited by the amount of organic substances available. Excessive amounts of methane can be produced, for example, during oxidation of boron carbide, which is used in BWR's as a neutron absorber material. Another important source is cable insulation. In a BWR, a large quantity of cables is placed below the pressure vessel. Thus a large quantity of pyrolyse gases will be produced, should the vessel fail. Organic iodides can be formed as a result of many different reactions, but at least in certain conditions the main reaction takes place between an organic radical produced by radiolysis and elemental iodine. A necessary requirement for prevention of organic iodide production is therefore that the pH in the containment water pools is kept high enough to eliminate formation of elemental iodine. In a typical BWR the suppression pool water is usually unbuffered. As a result, the pH may be dominated by chemicals introduced during an accident. If no system for adding basic chemicals is operable, the main factor affecting pool water pH may be hydrochloric acid released during cable degradation. Should this occur, the conditions could be very favorable for production of elemental iodine and, consequently, formation of organic iodides. Although high pH is necessary for iodine retention, it could have also adverse effects. High pH may, for example, accelerate corrosion of containment materials and alter the characteristics of the solid corrosion products. (author) 6 figs., 1 tab., 13 refs

  7. Irreversible processes kinetic theory

    CERN Document Server

    Brush, Stephen G

    2013-01-01

    Kinetic Theory, Volume 2: Irreversible Processes deals with the kinetic theory of gases and the irreversible processes they undergo. It includes the two papers by James Clerk Maxwell and Ludwig Boltzmann in which the basic equations for transport processes in gases are formulated, together with the first derivation of Boltzmann's ""H-theorem"" and a discussion of this theorem, along with the problem of irreversibility.Comprised of 10 chapters, this volume begins with an introduction to the fundamental nature of heat and of gases, along with Boltzmann's work on the kinetic theory of gases and s

  8. NORMOTHERMIC EXTRACORPOREAL PERFUSION IN SITU IN DECEASED ORGAN DONORS WITH IRREVERSIBLE CARDIAC ARREST AND ONE HOUR OF ASYSTOLE. 5-YEAR OUTCOMES OF KIDNEY TRANSPLANTATION

    Directory of Open Access Journals (Sweden)

    A. E. Skvortsov

    2016-01-01

    Full Text Available Aim. The global shortage of deceased organ donors caused increasing interest to the transplant program based on the use of organs from the donors with sudden irreversible cardiac arrest, or asystolic donors (DCD. Ischemia-reperfusion injury as a result of cardiac arrest remains a key problem that limits the use of organs from DCD. Our clinical study was intended to determine the acceptability of renal transplants derived from the DCD using extracorporeal perfusion in situ after 60 minutes of asystole. Materials and methods. In 2009–2014, St. Petersburg Organ Procurement Organization (OPO obtained kidneys from 29 DCD with critically expanded warm ischemic time (WIT. The design of this study was approved by the Scientifi c Board and Ethics Committee of the State Research Institute for Emergency Medicine (Decision 7/0615/09. Initially, no one of died patients was considered as potential organ donors. In case of failed advanced CPR the death of a patient was declared initiating the protocol of subnormothermic extracorporeal abdominal perfusion with ECMO, thrombolytics (strepokinase 1.5 mln U, and LD. The procedures were established by the authorized OPO team which arrived with perfusion equipment in 30–40 minutes after declaration of donors’ death. Mean WIT was 58.1 (19.39 minutes (Mean (SD. Resuscitated grafts were transplanted into 58 recipients. The outcomes of transplantation of resuscitated kidneys were compared to those of 112 KTx from 115 brain death donors (BDDs. Results. Immediate functioning of kidney grafts was observed in 28 (48.3% of 58 recipients. There were 4 cases of primary graft non-function. By the end of the fi rst post-transplant year there was an acute rejection rate of 12.1% (9 episodes of rejection in the DCD group vs. 23.2% (26 episodes of rejection in the BDD group (p < 0.05. The actuarial 5-year graft survival rate was 82.8% (n = 48 in DCD group, and 87.5% (n = 98 in BDD group (p > 0.05. Creatinine levels at the end

  9. Transient Inhibition of FGFR2b-ligands signaling leads to irreversible loss of cellular β-catenin organization and signaling in AER during mouse limb development.

    Directory of Open Access Journals (Sweden)

    Soula Danopoulos

    Full Text Available The vertebrate limbs develop through coordinated series of inductive, growth and patterning events. Fibroblast Growth Factor receptor 2b (FGFR2b signaling controls the induction of the Apical Ectodermal Ridge (AER but its putative roles in limb outgrowth and patterning, as well as in AER morphology and cell behavior have remained unclear. We have investigated these roles through graded and reversible expression of soluble dominant-negative FGFR2b molecules at various times during mouse limb development, using a doxycycline/transactivator/tet(O-responsive system. Transient attenuation (≤ 24 hours of FGFR2b-ligands signaling at E8.5, prior to limb bud induction, leads mostly to the loss or truncation of proximal skeletal elements with less severe impact on distal elements. Attenuation from E9.5 onwards, however, has an irreversible effect on the stability of the AER, resulting in a progressive loss of distal limb skeletal elements. The primary consequences of FGFR2b-ligands attenuation is a transient loss of cell adhesion and down-regulation of P63, β1-integrin and E-cadherin, and a permanent loss of cellular β-catenin organization and WNT signaling within the AER. Combined, these effects lead to the progressive transformation of the AER cells from pluristratified to squamous epithelial-like cells within 24 hours of doxycycline administration. These findings show that FGFR2b-ligands signaling has critical stage-specific roles in maintaining the AER during limb development.

  10. Organizing knowledge for tutoring fire loss prevention

    Science.gov (United States)

    Daniel L. Schmoldt

    1989-01-01

    The San Bernardino National Forest in southern California has recently developed a systematic approach to wildfire prevention planning. However, a comprehensive document or other mechanism for teaching this process to other prevention personnel does not exist. An intelligent tutorial expert system is being constructed to provide a means for learning the process and to...

  11. Stochastic dynamics and irreversibility

    CERN Document Server

    Tomé, Tânia

    2015-01-01

    This textbook presents an exposition of stochastic dynamics and irreversibility. It comprises the principles of probability theory and the stochastic dynamics in continuous spaces, described by Langevin and Fokker-Planck equations, and in discrete spaces, described by Markov chains and master equations. Special concern is given to the study of irreversibility, both in systems that evolve to equilibrium and in nonequilibrium stationary states. Attention is also given to the study of models displaying phase transitions and critical phenomema both in thermodynamic equilibrium and out of equilibrium. These models include the linear Glauber model, the Glauber-Ising model, lattice models with absorbing states such as the contact process and those used in population dynamic and spreading of epidemic, probabilistic cellular automata, reaction-diffusion processes, random sequential adsorption and dynamic percolation. A stochastic approach to chemical reaction is also presented.The textbook is intended for students of ...

  12. Extended Irreversible Thermodynamics

    CERN Document Server

    Jou, David

    2010-01-01

    This is the 4th edition of the highly acclaimed monograph on Extended Irreversible Thermodynamics, a theory that goes beyond the classical theory of irreversible processes. In contrast to the classical approach, the basic variables describing the system are complemented by non-equilibrium quantities. The claims made for extended thermodynamics are confirmed by the kinetic theory of gases and statistical mechanics. The book covers a wide spectrum of applications, and also contains a thorough discussion of the foundations and the scope of the current theories on non-equilibrium thermodynamics. For this new edition, the authors critically revised existing material while taking into account the most recent developments in fast moving fields such as heat transport in micro- and nanosystems or fast solidification fronts in materials sciences. Several fundamental chapters have been revisited emphasizing physics and applications over mathematical derivations. Also, fundamental questions on the definition of non-equil...

  13. Preventing Stress in Organizations How to Develop Positive Managers

    CERN Document Server

    Donaldson-Feilder, Emma; Yarker, Joanna

    2011-01-01

    Preventing Stress in Organizations:How to Develop Positive Managersoffers an innovative, evidence-based approach to help managers prevent and reduce workplace stress in their staff.Provides information on the critical skills managers must develop in order to prevent stress in their staff, and the key ongoing behaviours that promote a healthy work environmentShows practitioners in occupational psychology, HR, Health and Safety and related professions how positive management can be integrated into an organization???s existing practices and processesServes as an essential guide for managers thems

  14. Nonequilibrium and irreversibility

    CERN Document Server

    Gallavotti, Giovanni

    2014-01-01

    This book concentrates on the properties of the stationary states in chaotic systems of particles or fluids, leaving aside the theory of the way they can be reached. The stationary states of particles or of fluids (understood as probability distributions on microscopic configurations or on the fields describing continua) have received important new ideas and data from numerical simulations and reviews are needed. The starting point is to find out which time invariant distributions come into play in physics. A special feature of this book is the historical approach. To identify the problems the author analyzes the papers of the founding fathers Boltzmann, Clausius and Maxwell including translations of the relevant (parts of ) historical documents. He also establishes a close link between treatment of irreversible phenomena in statistical mechanics and the theory of chaotic systems at and beyond the onset of turbulence as developed by Sinai, Ruelle, Bowen (SRB) and others: the author gives arguments intending t...

  15. Organizing your practice for screening and secondary prevention among adults.

    Science.gov (United States)

    Knierim, Kyle E; Fernald, Douglas H; Staton, Elizabeth W; Nease, Donald E

    2014-06-01

    Prevention plays an important role in achieving the triple aim of decreasing per capita health care costs, improving the health of populations, and bettering the patient experience. Primary care is uniquely positioned to provide preventive services. External forces are aligning to support the transition of primary care from traditional models focused on disease-specific, acute episodes of care to new ways of organizing that are more patient centered, team based, and quality driven. By aligning leadership, building change capacity, and selectively choosing relevant processes to change, those practicing primary care can successfully organize their practice environment to deliver preventive services. Copyright © 2014 Elsevier Inc. All rights reserved.

  16. Mapping Collaborative Relations among Canada's Chronic Disease Prevention Organizations

    Science.gov (United States)

    Hanusaik, Nancy; Maximova, Katerina; Paradis, Gilles; O'Loughlin, Jennifer L.

    2016-01-01

    In the field of chronic disease prevention (CDP), collaborations between organizations provide a vital framework for intersectoral engagement and exchanges of knowledge, expertise and resources. However, little is known about how the structures of preventive health systems actually articulate with CDP capacity and outcomes. Drawing upon data from the Public Health Organizational Capacity Study – a repeat census of all public health organizations in Canada – we used social network analysis to map and examine interorganizational collaborative relationships in the Canadian preventive health system. The network of relationships obtained through our study shows that provincial boundaries remain a major factor influencing collaborative patterns. Not only are collaborations scarce on the interprovincial level but they are also mostly limited to links with federal and multi-provincial organizations. Given this finding, federal or multi-provincial organizations that occupy central bridging positions in the Canadian CDP collaborative structure should serve as key players for shaping CDP practices in the country. PMID:27585030

  17. Community Based Organizations in HIV/AIDS Prevention, Patient ...

    African Journals Online (AJOL)

    The main objective of this review is to provide a preliminary evaluation of the suitability of community-based organizations (CBOs) to contribute to HIV/AIDS prevention, care/support and control programs in Ethiopia. In order to put CBOs and programs in the context of HIV transmission and spread, the role of the Multisectoral ...

  18. Involving faith-based organizations in adolescent HIV prevention.

    Science.gov (United States)

    Williams, Terrinieka T; Griffith, Derek M; Pichon, Latrice C; Campbell, Bettina; Allen, Julie Ober; Sanchez, Jennifer C

    2011-01-01

    The rates of sexually transmitted infections (STIs; including HIV/AIDS) among African Americans in Flint, Michigan, are among the highest in the state. In Genesee County, where Flint is located, the incidence of HIV/AIDS cases increased at an average rate of 24% each year from 2003 to 2007 for adolescents between the ages of 13 and 19. YOUR Blessed Health (YBH) is a multilevel, faith-based HIV prevention program designed to increase HIV awareness and knowledge and reduce HIV risk behaviors among African American congregations. This article describes one of the five components of the intervention--training of faith leaders to implement a sexual health curriculum for adolescents in their congregations. Staff from YOUR Center, a community-based HIV service organization, and researchers from the University of Michigan, School of Public Health, partnered with faith-based organizations (FBOs) to address HIV/AIDS in Flint, Michigan. Participating FBOs selected faith leaders to be trained by YOUR Center staff to implement the YBH program in their congregations. Using the HIV Outreach, Prevention and Education (HOPE) curriculum, faith leaders from 20 FBOs provided HIV education to 212 adolescents in Flint, Michigan. Study findings demonstrate that faith leaders who participate in specific and ongoing HIV prevention education training can be useful sexual health resources for youth in faith-based settings. Implications for research and practice highlight the advantages of continued partnerships between FBOs and public health professionals in future HIV prevention efforts for adolescents.

  19. Irreversible Conversion of a Water-Ethanol Solution into an Organized Two-Dimensional Network of Alternating Supramolecular Units in a Hydrophobic Zeolite under Pressure.

    Science.gov (United States)

    Arletti, Rossella; Fois, Ettore; Gigli, Lara; Vezzalini, Giovanna; Quartieri, Simona; Tabacchi, Gloria

    2017-02-13

    Turning disorder into organization is a key issue in science. By making use of X-ray powder diffraction and modeling studies, we show herein that high pressures in combination with the shape and space constraints of the hydrophobic all-silica zeolite ferrierite separate an ethanol-water liquid mixture into ethanol dimer wires and water tetramer squares. The confined supramolecular blocks alternate in a binary two-dimensional (2D) architecture that remains stable upon complete pressure release. These results support the combined use of high pressures and porous networks as a viable strategy for driving the organization of molecules or nano-objects towards complex, pre-defined patterns relevant for the realization of novel functional nanocomposites. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Irreversibility in quantum mechanics

    International Nuclear Information System (INIS)

    Kadomtsev, Boris B

    2003-01-01

    From the Editorial Board. November 9, 2003 would have marked the seventy-fifth birthday of Boris Borisovich Kadomtsev, were he alive. An outstanding theoretical physicist, teacher, and enlightener, a prominent scientist in plasma physics and controlled nuclear fusion, Kadomtsev was also actively involved in science organization activities. In particular, from 1976 until his untimely death on August 19, 1998, Kadomtsev was the Editor-in-Chief of Physics-Uspekhi, and it is owing to his efforts that the journal improved notably during his tenure. Now, the Editorial Board, with gratitude and sorrow, would like to celebrate his birthday and to honor his blessed memory in these pages. There is, however, a rule - indeed an immutable tradition - in the journal that, except for the Personalia section, no anniversary can be marked in any way other than in a scientific publication. This rule was strictly observed under Kadomtsev, and certainly should not be violated now, even when honoring his memory. Fortunately, there is a video which remained of a lecture on modern problems of quantum physics that Kadomtsev delivered on May 12, 1997. Prepared for publication by M B Kadomtsev, the lecture allows the reader to revisit the heritage of B B Kadomtsev, to appreciate his logic in treating this very difficult area of physics, to hear his voice as it were, to recall Boris Borisovich Kadomtsev and to honor his memory. (methodological notes)

  1. Prevention of organic iodide formation in BWR`s

    Energy Technology Data Exchange (ETDEWEB)

    Karjunen, T. [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland); Laitinen, T.; Piippo, J.; Sirkiae, P. [VTT Manufacturing Technology (Finland)

    1996-12-01

    During an accident, many different forms of iodine may emerge. Organic iodides, such as methyl iodide and ethyl iodide, are relatively volatile, and thus their appearance leads to increased concentration of gaseous iodine. Since organic iodides are also relatively immune to most accident mitigation measures, such as sprays and filters, they can affect the accident source term significantly even when only a small portion of iodine is in organic form. Formation of organic iodides may not be limited by the amount of organic substances available. Excessive amounts of methane can be produced, for example, during oxidation of boron carbide, which is used in BWR`s as a neutron absorber material. Another important source is cable insulation. In a BWR, a large quantity of cables is placed below the pressure vessel. Thus a large quantity of pyrolyse gases will be produced, should the vessel fail. Organic iodides can be formed as a result of many different reactions, but at least in certain conditions the main reaction takes place between an organic radical produced by radiolysis and elemental iodine. A necessary requirement for prevention of organic iodide production is therefore that the pH in the containment water pools is kept high enough to eliminate formation of elemental iodine. In a typical BWR the suppression pool water is usually unbuffered. As a result, the pH may be dominated by chemicals introduced during an accident. If no system for adding basic chemicals is operable, the main factor affecting pool water pH may be hydrochloric acid released during cable degradation. Should this occur, the conditions could be very favorable for production of elemental iodine and, consequently, formation of organic iodides. Although high pH is necessary for iodine retention, it could have also adverse effects. High pH may, for example, accelerate corrosion of containment materials and alter the characteristics of the solid corrosion products. (author) 6 figs., 1 tab., 13 refs.

  2. Silica scale prevention technology using organic additive, Geogard SX

    Energy Technology Data Exchange (ETDEWEB)

    Baltazar, Almario; Garcia, Serafin; Solis, Ramonito; Fragata, Jimmy; Ellseworth, Lucero; Llenarizas, Leonardo; Tabuena, Joseph Erwin (PNOC Energy Development Corporation, Makati City (Philippines))

    1998-09-15

    A field trial on the application of an organic additive, phosphino carboxylic acid copolymer, was conducted in a geothermal system to evaluate its effectiveness in preventing silica deposition from brine containing ultra high silica concentration (1000-1300 ppm). Low polymer concentration was applied for about five months, and treatment efficiency based on silica concentrations in various sampling points ranged from 64 to 98%. Treatment efficiency improved as a function of time. Massive silica scaling in the fluid collection and disposal system was minimized.

  3. Global Warming, Irreversibility and Learning.

    OpenAIRE

    Ulph, Alistair; Ulph, David

    1997-01-01

    A number of economists have argued that the literature on the irreversibility effect implies that current abatement of greenhouse gas emissions should be greater when there is the possibility of obtaining better information in the future about the potential damages from global warming than when there is no possibility of obtaining better information. In this paper the authors show that even the simplest model of global warming does not satisfy either of Epstein's (1980) sufficient conditions,...

  4. Extremum principles for irreversible processes

    International Nuclear Information System (INIS)

    Hillert, M.; Agren, J.

    2006-01-01

    Hamilton's extremum principle is a powerful mathematical tool in classical mechanics. Onsager's extremum principle may play a similar role in irreversible thermodynamics and may also become a valuable tool. His principle may formally be regarded as a principle of maximum rate of entropy production but does not have a clear physical interpretation. Prigogine's principle of minimum rate of entropy production has a physical interpretation when it applies, but is not strictly valid except for a very special case

  5. Ecological optimization for generalized irreversible Carnot refrigerators

    Science.gov (United States)

    Chen, Lingen; Xiaoqin, Zhu; Sun, Fengrui; Wu, Chih

    2005-01-01

    The optimal ecological performance of a Newton's law generalized irreversible Carnot refrigerator with the losses of heat resistance, heat leakage and internal irreversibility is derived by taking an ecological optimization criterion as the objective, which consists of maximizing a function representing the best compromise between the exergy output rate and exergy loss rate (entropy production rate) of the refrigerator. Numerical examples are given to show the effects of heat leakage and internal irreversibility on the optimal performance of generalized irreversible refrigerators.

  6. Antibiotic use for irreversible pulpitis.

    Science.gov (United States)

    Agnihotry, Anirudha; Fedorowicz, Zbys; van Zuuren, Esther J; Farman, Allan G; Al-Langawi, Jassim Hasan

    2016-02-17

    Irreversible pulpitis, which is characterised by acute and intense pain, is one of the most frequent reasons that patients attend for emergency dental care. Apart from removal of the tooth, the customary way of relieving the pain of irreversible pulpitis is by drilling into the tooth, removing the inflamed pulp (nerve) and cleaning the root canal. However, a significant number of dentists continue to prescribe antibiotics to stop the pain of irreversible pulpitis.This review updates the previous version published in 2013. To assess the effects of systemic antibiotics for irreversible pulpitis. We searched the Cochrane Oral Health Group's Trials Register (to 27 January 2016); the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library 2015, Issue 12); MEDLINE via Ovid (1946 to 27 January 2016); EMBASE via Ovid (1980 to 27 January 2016), ClinicalTrials.gov (to 27 January 2016) and the WHO International Clinical Trials Registry Platform (to 27 January 2016). There were no language restrictions in the searches of the electronic databases. Randomised controlled trials which compared pain relief with systemic antibiotics and analgesics, against placebo and analgesics in the acute preoperative phase of irreversible pulpitis. Two review authors screened studies and extracted data independently. We assessed the quality of the evidence of included studies using GRADEpro software. Pooling of data was not possible and a descriptive summary is presented. One trial assessed at low risk of bias, involving 40 participants was included in this update of the review. The quality of the body of evidence was rated low for the different outcomes. There was a close parallel distribution of the pain ratings in both the intervention and placebo groups over the seven-day study period. There was insufficient evidence to claim or refute a benefit for penicillin for pain intensity. There was no significant difference in the mean total number of ibuprofen tablets over the

  7. Quality of stroke prevention in general practice: relationship with practice organization

    NARCIS (Netherlands)

    de Koning, Johan S.; Klazinga, Niek; Koudstaal, Peter J.; Prins, A. D.; Borsboom, Gerard J. J. M.; Mackenbach, Johan P.

    2005-01-01

    Objective. To investigate the relationship between elements of practice organization related to stroke prevention in general practice, and suboptimal preventive care preceding the occurrence of stroke. Design. This study was conducted among 69 Dutch general practitioners in the Rotterdam region.

  8. Quality of stroke prevention in general practice: relationship with practice organization

    NARCIS (Netherlands)

    J.S. de Koning (Johan); N.S. Klazinga (Niek); P.J. Koudstaal (Peter Jan); A. Prins (Ad); G.J.J.M. Borsboom (Gerard); J.P. Mackenbach (Johan)

    2005-01-01

    textabstractOBJECTIVE: To investigate the relationship between elements of practice organization related to stroke prevention in general practice, and suboptimal preventive care preceding the occurrence of stroke. DESIGN: This study was conducted among 69 Dutch general practitioners in the

  9. Anomalies, Unitarity and Quantum Irreversibility

    CERN Document Server

    Anselmi, D

    1999-01-01

    The trace anomaly in external gravity is the sum of three terms at criticality: the square of the Weyl tensor, the Euler density and Box R, with coefficients, properly normalized, called c, a and a', the latter being ambiguously defined by an additive constant. Unitarity and positivity properties of the induced actions allow us to show that the total RG flows of a and a' are equal and therefore the a'-ambiguity can be consistently removed through the identification a'=a. The picture that emerges clarifies several long-standing issues. The interplay between unitarity and renormalization implies that the flux of the renormalization group is irreversible. A monotonically decreasing a-function interpolating between the appropriate values is naturally provided by a'. The total a-flow is expressed non-perturbatively as the invariant (i.e. scheme-independent) area of the graph of the beta function between the fixed points. We test this prediction to the fourth loop order in perturbation theory, in QCD with Nf ~< ...

  10. Quantum nonequilibrium equalities with absolute irreversibility

    Science.gov (United States)

    Funo, Ken; Murashita, Yûto; Ueda, Masahito

    2015-07-01

    We derive quantum nonequilibrium equalities in absolutely irreversible processes. Here by absolute irreversibility we mean that in the backward process the density matrix does not return to the subspace spanned by those eigenvectors that have nonzero weight in the initial density matrix. Since the initial state of a memory and the postmeasurement state of the system are usually restricted to a subspace, absolute irreversibility occurs during the measurement and feedback processes. An additional entropy produced in absolutely irreversible processes needs to be taken into account to derive nonequilibrium equalities. We discuss a model of a feedback control on a qubit system to illustrate the obtained equalities. By introducing N heat baths each composed of a qubit and letting them interact with the system, we show how the entropy reduction via feedback control can be converted into work. An explicit form of extractable work in the presence of absolute irreversibility is given.

  11. Implications of the 2015 World Health Organization isoniazid preventive therapy recommendations on tuberculosis prevention efforts in Namibia.

    Science.gov (United States)

    Oloo, Stella Anne

    2016-07-01

    The World Health Organization recently released guidelines recommending 36-month use of isoniazid preventive therapy in adults and adolescents living with HIV in resource-limited settings. Namibia continues to grapple with one of the highest incidences of tuberculosis (TB) worldwide. Implementation of these guidelines requires considerations of TB epidemiology, health infrastructure, programmatic priorities and patient adherence. This article explores the challenges Namibia currently faces in its fight against TB and the implications of the new guidelines on Namibian TB prevention efforts.

  12. Alcohol Abuse Prevention: A Comprehensive Guide for Youth Organizations.

    Science.gov (United States)

    Boys' Clubs of America, New York, NY.

    This guide, the culmination of a three year Project TEAM effort by the Boys' Clubs of America, describes numerous strategies for developing an alcohol abuse prevention program. The core of this guide consists of program models developed by the Boys' Club project at seven pilot sites. The models presented cover the following areas: peer leadership,…

  13. Organizational capacity for chronic disease prevention: a survey of Canadian public health organizations.

    Science.gov (United States)

    Hanusaik, Nancy; O'Loughlin, Jennifer L; Kishchuk, Natalie; Paradis, Gilles; Cameron, Roy

    2010-04-01

    There are no national data on levels of organizational capacity within the Canadian public health system to reduce the burden of chronic disease. Cross-sectional data were collected in a national survey (October 2004 to April 2005) of all 216 national, provincial and regional-level organizations engaged in chronic disease prevention through primary prevention or healthy lifestyle promotion. Levels of organizational capacity (defined as skills and resources to implement chronic disease prevention programmes), potential determinants of organizational capacity and involvement in chronic disease prevention programming were compared in western, central and eastern Canada and across three types of organizations (formal public health organizations, non-governmental organizations and grouped organizations). Forty percent of organizations were located in Central Canada. Approximately 50% were formal public health organizations. Levels of skill and involvement were highest for activities that addressed tobacco control and healthy eating; lowest for stress management, social determinants of health and programme evaluation. The few notable differences in skill levels by provincial grouping favoured Central Canada. Resource adequacy was rated low across the country; but was lowest in eastern Canada and among formal public health organizations. Determinants of organizational capacity (organizational supports and partnerships) were highest in central Canada and among grouped organizations. These data provide an evidence base to identify strengths and gaps in organizational capacity and involvement in chronic disease prevention programming in the organizations that comprise the Canadian public health system.

  14. Successful pulpal anesthesia for symptomatic irreversible pulpitis.

    Science.gov (United States)

    Drum, Melissa; Reader, Al; Nusstein, John; Fowler, Sara

    2017-04-01

    Profound pulpal anesthesia after a successful inferior alveolar nerve block can be difficult to achieve when the clinical condition is a pulpal diagnosis of symptomatic irreversible pulpitis. The authors reviewed the literature as it relates to the anesthesia necessary for endodontic therapy of patients with painful, vital, mandibular teeth diagnosed with symptomatic irreversible pulpitis. Supplemental anesthetic techniques and medications are available that can be used to improve pulpal anesthesia for patients with the clinical condition of symptomatic irreversible pulpitis. The authors identified treatment recommendations for anesthesia in the case of symptomatic irreversible pulpitis based on a review of the available evidence. Copyright © 2017 American Dental Association. Published by Elsevier Inc. All rights reserved.

  15. Unreal perpetual motion machine, Rydberg constant and Carnot non-unitary efficiency as a consequence of the atomic irreversibility

    Science.gov (United States)

    Lucia, Umberto

    2018-02-01

    A perpetual motion machine is a completely ideal engine which cannot be realized. Carnot introduced the concept of the ideal engine which operates on a completely reversible cycle, without any dissipation, but with an upper limit in it. So, even in ideal condition without any dissipation, there is something that prevents the conversion of all the energy absorbed by an ideal reservoir into work. But what is the cause of irreversibility? Here we highlight the atomic nature of this irreversibility, proving that it is no more than the continuous interaction of the atoms with the surrounding field. The macroscopic irreversibility is the consequence of the microscopic irreversibility.

  16. Inter-govermental organizations and preventing conflicts : political practice since the end of the Cold War

    NARCIS (Netherlands)

    Walraven, van K.; Walraven, van K.

    1998-01-01

    This volume is the result of an international symposium on early warning and conflict prevention, held in The Hague in 1996. Two chapters deal with Africa. They investigate the role regional organizations - whether intergovernmental, State or non-State - can play in the prevention of conflicts in

  17. Fundamental optimal relation of a generalized irreversible Carnot ...

    Indian Academy of Sciences (India)

    The generalized irreversible Carnot heat pump model incorporates several internal and external irreversibilities, such as heat resistance, bypass heat leakage, friction, turbulence and other undesirable irreversibility factors. The added irreversibilities besides heat resistance are characterized by a constant parameter and a ...

  18. Enhancing Community-Based Organizations' Capacity for HIV/AIDS Education and Prevention

    Science.gov (United States)

    Mayberry, Robert M.; Daniels, Pamela; Yancey, Elleen M.; Akintobi, Tabia Henry; Berry, Jamillah; Clark, Nicole; Dawaghreh, Ahmad

    2009-01-01

    The catalytic potential of community-based organizations to promote health, prevent disease, and address racial, ethnic, and socio-economic disparities in local communities is well recognized. However, many CBOs, particularly, small- to medium-size organizations, lack the capacity to plan, implement, and evaluate their successes. Moreover, little…

  19. Ultrafast irreversible phototautomerization of o-nitrobenzaldehyde.

    Science.gov (United States)

    Migani, Annapaola; Leyva, Verónica; Feixas, Ferran; Schmierer, Thomas; Gilch, Peter; Corral, Inés; González, Leticia; Blancafort, Lluís

    2011-06-14

    o-Nitrobenzaldehyde is photolabile because of an irreversible phototautomerization, whereas comparable aromatic compounds function as photoprotectors because the tautomerization is reversible. In this experimental and theoretical study we track down the cause of this difference to the electronic changes that occur during the tautomerization. This journal is © The Royal Society of Chemistry 2011

  20. A kinetic equation for irreversible aggregation

    International Nuclear Information System (INIS)

    Zanette, D.H.

    1990-09-01

    We introduce a kinetic equation for describing irreversible aggregation in the ballistic regime, including velocity distributions. The associated evolution for the macroscopic quantities is studied, and the general solution for Maxwell interaction models is obtained in the Fourier representation. (author). 23 refs

  1. Assessing and Mobilizing Faith Organizations to Implement Childhood Obesity Prevention Advocacy Strategies.

    Science.gov (United States)

    Bozlak, Christine T; Kenady, James M; Becker, Adam B

    2018-01-01

    Childhood obesity remains a public health problem requiring mobilization across diverse social and political sectors. The faith-based sector can contribute to obesity prevention advocacy when existing resources are supported and leveraged. This article describes an advocacy resource assessment conducted in six Chicago faith organizations. Key administrators and congregation members were surveyed to identify organizational resources that could be mobilized for childhood obesity prevention advocacy. Survey data were analyzed using SPSS and Excel. Descriptive statistics were calculated for each organization and for all combined. Organizational resources for advocacy were identified, with varying degrees of resources within organizations. Congregation members and faith leaders expressed interest in advocacy training and activities but acknowledged competing organizational priorities. Participating organizations received a stipend to pursue recommended action items based on their assessment. Faith organizations have unique resources and human capital and can be key partners in childhood obesity prevention. Conducting an assessment prior to planning interventions and advocacy approaches can strengthen partnerships, leverage assets among partners, and ensure efforts are relevant and beneficial for faith organizations. It may also be strategic to incorporate funding in grant budgets in order to empower faith organizations to act on findings from the assessment process.

  2. Overcoming the organization-practice barrier in sports injury prevention: A nonhierarchical organizational model.

    Science.gov (United States)

    Dahlström, Ö; Jacobsson, J; Timpka, T

    2015-08-01

    The organization of sports at the national level has seldom been included in scientific discussions of sports injury prevention. The aim of this study was to develop a model for organization of sports that supports prevention of overuse injuries. The quality function deployment technique was applied in seminars over a two-season period to develop a national organizational structure for athletics in Sweden that facilitates prevention of overuse injuries. Three central features of the resulting model for organization of sports at the national level are (a) diminishment of the organizational hierarchy: participatory safety policy design is introduced through annual meetings where actors from different sectors of the sporting community discuss training, injury prevention, and sports safety policy; (b) introduction of a safety surveillance system: a ubiquitous system for routine collection of injury and illness data; and (c) an open forum for discussion of safety issues: maintenance of a safety forum for participants from different sectors of the sport. A nonhierarchical model for organization of sports at the national level - facilitated by modern information technology - adapted for the prevention of overuse injuries has been developed. Further research is warranted to evaluate the new organizational model in prospective effectiveness studies. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  3. PRIMARY PREVENTION IS? A GLOBAL PERSPECTIVE ON HOW ORGANIZATIONS ENGAGING MEN IN PREVENTING GENDER-BASED VIOLENCE CONCEPTUALIZE AND OPERATIONALIZE THEIR WORK

    Science.gov (United States)

    Storer, Heather L.; Casey, Erin A.; Carlson, Juliana; Edleson, Jeffrey L.; Tolman, Richard M.

    2014-01-01

    Engaging men in addressing violence against women (VAW) has become a strategy in the global prevention of gender-based violence. Concurrently, Western public health frameworks have been utilized to guide prevention agendas worldwide. Using qualitative methods, this study describes how global anti-violence organizations that partner with men conceptualize primary prevention in their work. Findings suggest that ‘primary prevention’ is not a fixed term in the context of VAW and that front-line prevention work challenges rigidly delineated distinctions between levels of prevention. Much can be learned from global organizations’ unique and contextualized approaches to the prevention of VAW. PMID:26333283

  4. Irreversible and irretrievable commitments of material resources

    International Nuclear Information System (INIS)

    1976-06-01

    In accordance with 10 CFR Part 51, ''Licensing and Regulatory Policy and Procedures for Environmental Protection,'' applicants are required to discuss any irreversible and irretrievable commitments of resources that would be involved in a proposed action, should it be implemented. The construction and operation of nuclear power stations involve commitments of such resources as water, fuel, and materials. The guide presented identifies a report on material resources that forms a basis acceptable to the NRC staff for required discussions of irreversible and irretrievable commitments of material resources involved in the construction of a 1000 MWe pressurized water reactor. The guide describes numerical estimates useful in all such discussions. It also provides methods of computation that may be referenced

  5. Optima and bounds for irreversible thermodynamic processes

    International Nuclear Information System (INIS)

    Hoffmann, K.H.

    1990-01-01

    In this paper bounds and optima for irreversible thermodynamic processes and their application in different fields are discussed. The tools of finite time thermodynamics are presented and especially optimal control theory is introduced. These methods are applied to heat engines, including models of the Diesel engine and a light-driven engine. Further bounds for irreversible processes are introduced, discussing work deficiency and its relation to thermodynamic length. Moreover the problem of dissipation in systems composed of several subsystems is studied. Finally, the methods of finite time thermodynamics are applied to thermodynamic processes described on a more microscopic level. The process used as an example is simulated annealing. It is shown how optimal control theory is applied to find the optimal cooling schedule for this important stochastic optimization method

  6. Irreversible Investment with Embodied Technological Progress

    OpenAIRE

    Bruno de Oliveira Cruz; Aude Pommeret

    2015-01-01

    In this paper, we propose to explain capital accumulation in a stochastic framework by taking into account the two main motives for investment. Specifically, firms invest to expand capacity and to replace old machines. The model considers irreversible investment under uncertainty and embodied technological progress. It is shown to be consistent with the following empirical observations: Investment is lumpy and infrequent at the firm level; firms can invest even if they have not reached full c...

  7. Mathematical models and equilibrium in irreversible microeconomics

    Directory of Open Access Journals (Sweden)

    Anatoly M. Tsirlin

    2010-07-01

    Full Text Available A set of equilibrium states in a system consisting of economic agents, economic reservoirs, and firms is considered. Methods of irreversible microeconomics are used. We show that direct sale/purchase leads to an equilibrium state which depends upon the coefficients of supply/demand functions. To reach the unique equilibrium state it is necessary to add either monetary exchange or an intermediate firm.

  8. Microscopic Irreversibility and the H Theorem

    Science.gov (United States)

    Magpantay, Jose A.

    2013-02-01

    Time-reversal had always been assumed to be a symmetry of physics at the fundamental level. In this paper we will explore the violations of time-reversal symmetry at the fundamental level and the consequence on thermodynamic systems. First, we will argue from current physics that the universe dynamics is not time-reversal invariant. Second, we will argue that any thermodynamic system cannot be isolated completely from the universe. We then discuss how these two make the dynamics of thermodynamics systems very weakly irreversible at the classical and quantum level. Since time-reversal is no longer a symmetry of realistic systems, the problem of how macroscopic irreversibility arises from microscopic reversibility becomes irrelevant because there is no longer microscopic reversibility. At the classical level of a thermodynamic system, we show that the H theorem of Boltzmann is still valid even without microscopic reversibility. We do this by deriving a modified H theorem, which still shows entropy monotonically increasing. At the quantum level, we explicitly show the effect of CP violation, small irreversible changes on the internal states of the nuclear and atomic energy levels of thermodynamic systems. Thus, we remove Loschmidt's objection to Boltzmann's ideas.

  9. Irreversible properties of YBCO coated conductors

    International Nuclear Information System (INIS)

    Vostner, A.

    2001-02-01

    Over the past few years substantial efforts were made to optimize the fabrication techniques of various high temperature superconductors for commercial applications. In addition to Bi-2223 tapes, Y-123 coated conductors have the potential for large-scale production and are considered as the second generation of superconducting 'wires' for high current applications. This work reports on magnetic and transport current investigations of Y-123 thick films deposited on either single crystalline substrates by liquid phase epitaxy (LPE) or on metallic substrates by pulsed laser deposition (PLD). At the beginning, a short introduction of the general idea of a coated conductor and of the different production techniques is presented, followed by a description of the different experimental set-ups and the evaluation methods. The main part starts with the results obtained from SQUID magnetometry and ac-susceptibility measurements including the transition temperatures T c , the field dependence of the magnetic critical current densities and the irreversibility lines. In addition, some issues concerning the granular structure and the inter- and intragranular current distribution of the superconducting films are discussed. The investigations by transport currents are focused on the behavior of the application relevant irreversible parameters. These are the angular and the field dependence of the critical transport current densities at 77 and 60 K, as well as the temperature dependence of the irreversibility fields up to 6 T. To gain more insight into the defect structure of the films, neutron irradiation studies were performed on some samples. The introduction of these artificial pinning centers causes large enhancements of the magnetic J c in LPE specimens for the field parallel to the c-axis (H//c) at higher temperatures and magnetic fields. The granular structure of the samples does not change up to the highest neutron fluences. However, the enhancements of the transport J c

  10. Surfing the web during pandemic flu: availability of World Health Organization recommendations on prevention

    Directory of Open Access Journals (Sweden)

    Ravà Lucilla

    2010-09-01

    Full Text Available Abstract Background People often search for information on influenza A(H1N1v prevention on the web. The extent to which information found on the Internet is consistent with recommendations issued by the World Health Organization is unknown. Methods We conducted a search for "swine flu" accessing 3 of the most popular search engines through different proxy servers located in 4 English-speaking countries (Australia, Canada, UK, USA. We explored each site resulting from the searches, up to 4 clicks starting from the search engine page, analyzing availability of World Health Organization recommendations for swine flu prevention. Results Information on hand cleaning was reported on 79% of the 147 websites analyzed; staying home when sick was reported on 77.5% of the websites; disposing tissues after sneezing on 75.5% of the websites. Availability of other recommendations was lower. The probability of finding preventative recommendations consistent with World Health Organization varied by country, type of website, and search engine. Conclusions Despite media coverage on H1N1 influenza, relevant information for prevention is not easily found on the web. Strategies to improve information delivery to the general public through this channel should be improved.

  11. Surfing the web during pandemic flu: availability of World Health Organization recommendations on prevention.

    Science.gov (United States)

    Gesualdo, Francesco; Romano, Mariateresa; Pandolfi, Elisabetta; Rizzo, Caterina; Ravà, Lucilla; Lucente, Daniela; Tozzi, Alberto E

    2010-09-20

    People often search for information on influenza A(H1N1)v prevention on the web. The extent to which information found on the Internet is consistent with recommendations issued by the World Health Organization is unknown. We conducted a search for "swine flu" accessing 3 of the most popular search engines through different proxy servers located in 4 English-speaking countries (Australia, Canada, UK, USA). We explored each site resulting from the searches, up to 4 clicks starting from the search engine page, analyzing availability of World Health Organization recommendations for swine flu prevention. Information on hand cleaning was reported on 79% of the 147 websites analyzed; staying home when sick was reported on 77.5% of the websites; disposing tissues after sneezing on 75.5% of the websites. Availability of other recommendations was lower. The probability of finding preventative recommendations consistent with World Health Organization varied by country, type of website, and search engine. Despite media coverage on H1N1 influenza, relevant information for prevention is not easily found on the web. Strategies to improve information delivery to the general public through this channel should be improved.

  12. Is the Use of Dexamethasone Effective in Controlling Pain Associated with Symptomatic Irreversible Pulpitis? A Systematic Review.

    Science.gov (United States)

    Nogueira, Brenna M L; Silva, Ludmylla G; Mesquita, Carla R M; Menezes, Sílvio A F; Menezes, Tatiany O A; Faria, Antônio G M; Porpino, Mariana T M

    2018-03-20

    Endodontic pain is a symptom of pulpal and/or periapical inflammation. One strategy for pain reduction is using medications, such as dexamethasone. A definitive protocol for preventing and controlling pain caused by irreversible pulpitis during endodontic treatment has not yet been established. This is a systematic review to answer the following question: is the use of dexamethasone effective in controlling pain associated with symptomatic irreversible pulpitis? This study was registered in the PROSPERO database (CRD42017058704), and Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement recommendations were followed. MEDLINE, Scopus, ScienceDirect, Web of Science, Latin American Caribbean Health Sciences Literature, Cochrane Library, and Google Scholar databases were used in our research. No restrictions were applied to dates or language of publication. All records identified electronically were organized and evaluated by 2 independent authors, and, in case of doubt, a third author made the decision. The Cochrane Collaboration tool was used. The data were analyzed with RevMan 5 software (The Cochrane Collaboration, Copenhagen, Denmark), and data from eligible studies were dichotomous (with and without pain). A total of 4825 studies were identified. After screening, 523 studies were selected, and, after careful evaluation, only 5 articles remained. All meta-analyses revealed a global effect (P irreversible pulpitis may be alleviated by administering 4 mg dexamethasone either by mouth or through intraligamentary and mainly supraperiosteal injections into the root canal for up to 24 hours. Copyright © 2018 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  13. Entry Inhibitors: A Perspective for Prevention of Hepatitis C Virus Infection in Organ Transplantation.

    Science.gov (United States)

    Colpitts, Che C; Chung, Raymond T; Baumert, Thomas F

    2017-09-08

    Entry inhibitors are emerging as an attractive class of therapeutics for hepatitis C virus (HCV) infection. Entry inhibitors target either virion-associated factors or cellular factors necessary for infection. By blocking entry into cells, entry inhibitors prevent both the establishment of persistent reservoirs and the emergence of resistant variants during viral replication. Furthermore, entry inhibitors protect naïve cells from virus-induced alterations. Combining entry inhibitors with direct-acting antivirals (DAAs) may therefore improve treatment outcomes, particularly in the context of organ transplantation. The role of DAAs in transplantation, while still under clinical investigation, carries the risk of recipient infection and HCV-induced disease, since DAAs act only after infection is established. Thus, entry inhibitors provide a perspective to improve patient outcomes during organ transplantation. Applying this approach for transplant of organs from HCV-positive donors to HCV-negative recipients may also contribute to alleviate the medical burden of organ shortage.

  14. Plasma free reversible and irreversible microfluidic bonding.

    Science.gov (United States)

    Chu, M; Nguyen, T T; Lee, E K; Morival, J L; Khine, M

    2017-01-17

    We demonstrate a facile, plasma free process to fabricate both reversibly and irreversibly sealed microfluidic chips using a PDMS-based adhesive polymer mixture. This is a versatile method that is compatible with current PDMS microfluidics processes. It allows for easier fabrication of multilayer microfluidic devices and is compatible with micropatterning of proteins for cell culturing. When combined with our Shrinky-Dink microfluidic prototyping, complete microfluidic device fabrication can be performed without the need for any capital equipment, making microfluidics accessible to the classroom.

  15. Statistical mechanics out of equilibrium the irreversibility

    International Nuclear Information System (INIS)

    Alvarez Estrada, R. F.

    2001-01-01

    A Round Table about the issue of Irreversibility and related matters has taken place during the last (20th) Statistical Mechanics Conference, held in Paris (July 1998). This article tries to provide a view (necessarily limited, and hence, uncompleted) of some approaches to the subject: the one based upon deterministic chaos (which is currently giving rise to a very active research) and the classical interpretation due to Boltzmann. An attempt has been made to write this article in a self-contained way, and to avoid a technical presentation wherever possible. (Author) 29 refs

  16. Stress Prevention@Work: a study protocol for the evaluation of a multifaceted integral stress prevention strategy to prevent employee stress in a healthcare organization: a cluster controlled trial

    NARCIS (Netherlands)

    Hoek, R.J.A.; Havermans, B.M.; Houtman, I.L.D.; Brouwers, E.P.M.; Heerkens, Y.F.; Zijlstra-Vlasveld, M.C.; Anema, J.R.; Beek, A.J. van der; Boot, C.R.L.

    2017-01-01

    Background. Adequate implementation of work-related stress management interventions can reduce or prevent work-related stress and sick leave in organizations. We developed a multifaceted integral stress-prevention strategy for organizations from several sectors that includes a digital platform and

  17. Stress Prevention@Work : A study protocol for the evaluation of a multifaceted integral stress prevention strategy to prevent employee stress in a healthcare organization: a cluster controlled trial

    NARCIS (Netherlands)

    Hoek, R.J.A.; Havermans, B.M.; Houtman, I.L.D.; Brouwers, E.P.M.; Heerkens, Y.F.; Zijlstra-vlasveld, M.C.; Anema, J.R.; van der Beek, A.J.; Boot, C.R.L.

    2018-01-01

    Adequate implementation of work-related stress management interventions can reduce or prevent work-related stress and sick leave in organizations. We developed a multifaceted integral stress-prevention strategy for organizations from several sectors that includes a digital platform and collaborative

  18. [The organization of the preventive work in educational institutions: problems and solutions].

    Science.gov (United States)

    Kuchma, V R; Sokolova, S B; Rapoport, I K; Makarova, A Yu

    2015-01-01

    Prevention measures are relevant for children and adolescents as among them there is the high prevalence of leading risk factors for chronic diseases. For the improvement of the preventive work it is necessary the introduction of amendments into the legislative documents and orders of the Ministry of Health, governing health care for children and adolescents in educational organizations. The consistent methodology for primary health care must be provided with the appropriate protocols. It is necessary to perform the systematic work on the reduction of the prevalence of risk factors for children's health and a healthy lifestyle. The number of doctors and nurses in the preschool and educational institutions is insufficient, and in organizations of primary and secondary vocational education is disastrous. Medical personnel departments of medical assistance to students due to the excessive load is not capable to fufill all of their functional responsibilities. Due to the low wages there is a constant reduction of health workers in schools and kindergartens. In the paper there are proposed measures aimed at improving the quality of preventive work in educational organizations.

  19. Prevention

    Science.gov (United States)

    ... Error processing SSI file About Heart Disease & Stroke Prevention Heart disease and stroke are an epidemic in ... secondhand smoke. Barriers to Effective Heart Disease & Stroke Prevention Many people with key risk factors for heart ...

  20. The disaster prevention awareness of foreign residents and disaster management of organizations for foreign employees

    Science.gov (United States)

    Xin, Tan Yen; Sugiki, Nao; Matsuo, Kojiro

    2017-10-01

    Japan is known to have many natural disasters occurrences, especially in recent years, the seismic hazard named "Nankai-trough Disastrous Earthquake" of magnitude 9(M) was predicted and will have caused huge damages. Therefore, disaster management should be well planned and executed to ensure minimal amount of victims and damages from disaster. However, foreign residents are mostly vulnerable and ill-equipped to face such consequences compared to Japanese residents, especially when there is limited information available for foreigners presently. As the influx of foreigner migration has been steadily increasing annually, it is vital for disaster management to be compulsively planned to cope up with the great variety of foreigners' needs from diverse backgrounds accordingly. The purpose of this study is to comprehend foreign residents' disaster prevention awareness, in order to provide a more effective information provision on disaster management, so as to help improve their disaster prevention awareness. Thus, this study is set in Toyohashi city, and the methodology used is by conducting two questionnaires. Firstly, to have an accurate understanding on the awareness of foreign residents towards disasters prevention, the questionnaire is conducted towards foreign university students, on pertinent issues such as on the degree of preparedness and their matters of concern of which is related to natural disasters. Secondly, to comprehend disaster management of organizations, the other focuses on preventive measures adopted by manufacturing industry organizations, such as types of preventive measures as a whole and on the issues and challenges encountered during foreign employee-related enforcement of disaster management. Finally, based both results of the questionnaire, the key factors on effective information provision of disaster management is considered.

  1. Anistropically varying conductivity in irreversible electroporation simulations.

    Science.gov (United States)

    Labarbera, Nicholas; Drapaca, Corina

    2017-11-01

    One recent area of cancer research is irreversible electroporation (IRE). Irreversible electroporation is a minimally invasive procedure where needle electrodes are inserted into the body to ablate tumor cells with electricity. The aim of this paper is to propose a mathematical model that incorporates a tissue's conductivity increasing more in the direction of the electrical field as this has been shown to occur in experiments. It was necessary to mathematically derive a valid form of the conductivity tensor such that it is dependent on the electrical field direction and can be easily implemented into numerical software. The derivation of a conductivity tensor that can take arbitrary functions for the conductivity in the directions tangent and normal to the electrical field is the main contribution of this paper. Numerical simulations were performed for isotropic-varying and anisotropic-varying conductivities to evaluate the importance of including the electrical field's direction in the formulation for conductivity. By starting from previously published experimental results, this paper derived a general formulation for an anistropic-varying tensor for implementation into irreversible electroporation modeling software. The anistropic-varying tensor formulation allows the conductivity to take into consideration both electrical field direction and magnitude, as opposed to previous published works that only took into account electrical field magnitude. The anisotropic formulation predicts roughly a five percent decrease in ablation size for the monopolar simulation and approximately a ten percent decrease in ablation size for the bipolar simulations. This is a positive result as previously reported results found the isotropic formulation to overpredict ablation size for both monopolar and bipolar simulations. Furthermore, it was also reported that the isotropic formulation overpredicts the ablation size more for the bipolar case than the monopolar case. Thus, our

  2. Irreversible and reversible components in the genesis of hypertension by sodium chloride (salt).

    Science.gov (United States)

    Tekol, Yalcin

    2008-01-01

    Despite the abundant studies and overwhelming evidences demonstrating the essential role of salt (sodium chloride) for developing "essential" hypertension (EH), the controversies about salt-hypertension (HT) relations are still continuing. One of important mistakes in this topic is assuming that the HT-producing effect of salt is reversible. The present paper explains the complex nature of salt-HT relations. The deduction was made basing on the studies which investigate the relations between salt and HT. Animal experiments show that HT-producing effect of salt contains irreversible and reversible components. The existence of irreversible component manifests itself in this way: the blood pressure (BP) does not recede to the natural values despite removing of salt exposure. The proportion of BP decreasing after salt exposure termination belongs to the reversible component. Available evidences indicate that the irreversible component is developed in utero, during suckling and, generally, in prepubertal period secondary to salt exposure, however, if the salt exposure extends over more than one period, the HT may be intensified. The consequences of salt exposure during early life of human beings have not been investigated as detailed as in experimental animals, however, there are some clinical trials and epidemiological observations indicating that, similar to experimental animals, irreversible and reversible components are also developed in man during the genesis of HT. By the introduction of irreversible and reversible components notion, some obscured items on salt-HT relations can be clarified. For example, some intervention studies could not find dramatic relations between salt and HT, because these interventions modify only the reversible component, but irreversible component remains unchanged. As a result, salt exposure is detrimental for each period of life. For eradication of HT, it is prerequisite to prevent all individuals (especially pregnant or lactating

  3. ASSESSMENT OF THE ORGANIZATION OF PREVENTION OF DENTAL DISEASES AND DENTAL CARE TO RETIREES

    Directory of Open Access Journals (Sweden)

    Anna Vladimirovna Fomina

    2017-05-01

    Full Text Available Background: To give a characteristic of the preventation of disease and dental care to military retirees organization based on the research of self-reported health status, dental health status and assessment of the dental care level. Materials and methods: The research is based on sociological research of military retirees’ self-reported health status materials (300 profiles and analyses of the sample cards from medical documentation about recourses for dental care, orthopedic care, about recourses in medical institution which gives medical care for this contingent (300 cards. Results: A medico-social characteristics of military retirees opinion about organization of dental care and prevention of dental diseases was made. Among the reasons for going dentist the absolutely biggest one is necessary to make a dental prosthesis because of missing teeth (76%. Only 24,1% of respondents are following dentist’s recommendations. In most cases dentist can make a necessary dental care, but only in 7,2% there is no result which is linked to patient’s missing the second medical reception. Conclusion: A low level of medical literacy knowledge about prevention of dental diseases and their treatment among military retirees was recorder. This research affirms the need of development the events about military retirees rehabilitation complex.

  4. Assessing Capacity to Promote Science-Based Programs: A Key Informant Study of State Teen Pregnancy Prevention Organizations

    Science.gov (United States)

    Saunders, Edward; Sabri, Bushra; Huberman, Barbara; Klaus, T. W.; Davis, Laura

    2011-01-01

    The purpose of this qualitative study was to identify significant external and internal challenges that state organization leaders face in promoting science-based teen pregnancy prevention programs within their states. The state organization administrators were chosen because their organizations were funded by the U.S. Centers for Disease Control…

  5. INTERNATIONAL AND REGIONAL ORGANIZATIONS WITH ATTRIBUTES AND PREOCCUPATIONS IN PREVENTING AND FIGHTING AGAINST CYBERCRIME AND THEIR MAIN ACCOMPLISHMENTS

    OpenAIRE

    Gheorghe-Iulian Ioniţă; Ștefania-Diana Ioniţă-Burda

    2011-01-01

    At global level, there are various organizations which are constantly concerned with the analysis of the latest manifestations and evolution of cybercrime, setting up work groups to develop strategies for the prevention and fight of cybercrimes. Besides these international organizations which act globally, several other organizations focus on certain regions, dealing with issues related to cybercrime.

  6. Entropy, Extropy and the Physical Driver of Irreversibility

    Directory of Open Access Journals (Sweden)

    Attila Grandpierre

    2012-06-01

    Full Text Available We point out that the fundamental irreversibility of Nature requires the introduction of a suitable measure for the distance from equilibrium. We show that entropy, which is widely held to be such a measure, suffers from the problem that it does not have a physical meaning, since it is introduced on the basis of mathematical arguments. As a consequence, the basic physics beyond irreversibility has remained obscure. We present here a simple but transparent physical approach for solving the problem of irreversibility. This approach shows that extropy, the fundamental thermodynamic variable introduced by Katalin Martinás, is the suitable measure for the distance from equilibrium, since it corresponds to the actual driver of irreversible processes. Since extropy explicitly contains in its definition all the general thermodynamic forces that drive irreversible processes, extropy is the suitable physical measure of irreversibility.

  7. Competing irreversible cooperative reactions on polymer chains

    International Nuclear Information System (INIS)

    Evans, J.W.; Hoffman, D.K.; Burgess, D.R.

    1984-01-01

    We analyze model processes involving competition between several irreversible reactions at the sites of a 1D, infinite, uniform polymer chain. These reactions can be cooperative, i.e., the corresponding rates depend on the state of the surrounding sites. An infinite hierarchy of rate equations is readily derived for the probabilities of various subconfigurations. By exploiting a shielding property of suitable blocks of unreacted sites, we show how exact hierarchy truncation and solution is sometimes possible. The behavior of solutions is illustrated in several cases by plotting families of ''reaction trajectories'' for varying ratios of reactant concentrations. As a specific application, we consider competition between coordination of ZnCl 2 to pairs of oxygen atoms and to single oxygen atoms in poly(propylene oxide). The observed glass transition temperature behavior is eludicated

  8. Exergetic sustainability evaluation of irreversible Carnot refrigerator

    Science.gov (United States)

    Açıkkalp, Emin

    2015-10-01

    Purpose of this paper is to assess irreversible refrigeration cycle by using exergetic sustainability index. In literature, there is no application of exergetic sustainability index for the refrigerators and, indeed, this index has not been derived for refrigerators. In this study, exergetic sustainability indicator is presented for the refrigeration cycle and its relationships with other thermodynamics parameters including COP, exergy efficiency, cooling load, exergy destruction, ecological function and work input are investigated. Calculations are conducted for endoreversible and reversible cycles and then results obtained from the ecological function are compared. It is found that exergy efficiency, exergetic sustainable index reduce 47.595% and 59.689% and rising at the COP is 99.888% is obtained for endoreversible cycle. Similarly, exergy efficiency and exergetic sustainability index reduce 90.163% and 93.711% and rising of the COP is equal to 99.362%.

  9. Diffusion of irreversible energy technologies under uncertainty

    Energy Technology Data Exchange (ETDEWEB)

    Cacallo, J.D.; Sutherland, R.J.

    1993-09-01

    This paper presents a model of technology diffusion is consistent with characteristics of participants in most energy markets. Whereas the models used most widely for empirical research are based on the assumption that the extended delays in adoption of cost-saving innovations are the result of either lack of knowledge about the new processes or heterogeneity across potential adopters, the model presented in this paper is based on the strategic behavior by firms. The strategic interdependence of the firms` decisions is rooted in spillover effects associated with an inability to exclude others from the learning-by-doing acquired when a firm implements a new technology. The model makes extensive use of recent developments in investment theory as it relates irreversible investments under uncertainty.

  10. Chemical kinetics, stochastic processes, and irreversible thermodynamics

    CERN Document Server

    Santillán, Moisés

    2014-01-01

    This book brings theories in nonlinear dynamics, stochastic processes, irreversible thermodynamics, physical chemistry, and biochemistry together in an introductory but formal and comprehensive manner.  Coupled with examples, the theories are developed stepwise, starting with the simplest concepts and building upon them into a more general framework.  Furthermore, each new mathematical derivation is immediately applied to one or more biological systems.  The last chapters focus on applying mathematical and physical techniques to study systems such as: gene regulatory networks and ion channels. The target audience of this book are mainly final year undergraduate and graduate students with a solid mathematical background (physicists, mathematicians, and engineers), as well as with basic notions of biochemistry and cellular biology.  This book can also be useful to students with a biological background who are interested in mathematical modeling, and have a working knowledge of calculus, differential equatio...

  11. Principle of maximum entropy and irreversible processes

    International Nuclear Information System (INIS)

    Grandy, W.T. Jr.

    1980-01-01

    More than twenty years have passed since E.T. Jaynes pioneered the information-theoretic approach to the foundations of statistical mechanics. In the intervening period numerous applications have been worked out and new insights developed into traditional problems. Although the natural extension of these ideas to nonequilibrium statistical mechanics and irreversible processes has also been formulated, and both theory and applications have been considerably developed, much of this work has not appeared in the open literature. Yet the basic ideas and consequent theory seem to have an extraordinary unifying and illumination effect on the foundations of the many-body problem, as well as providing a transparent conceptual basis from which to view various groups of problems not previously formulated in a particularly sharp way. The aim of this review is to summarize these developements in the context of the principle of maximum entropy. (orig.)

  12. On the existence of physiological age based on functional hierarchy: a formal definition related to time irreversibility.

    Science.gov (United States)

    Chauvet, Gilbert A

    2006-09-01

    The present approach of aging and time irreversibility is a consequence of the theory of functional organization that I have developed and presented over recent years (see e.g., Ref. 11). It is based on the effect of physically small and numerous perturbations known as fluctuations, of structural units on the dynamics of the biological system during its adult life. Being a highly regulated biological system, a simple realistic hypothesis, the time-optimum regulation between the levels of organization, leads to the existence of an internal age for the biological system, and time-irreversibility associated with aging. Thus, although specific genes are controlling aging, time-irreversibility of the system may be shown to be due to the degradation of physiological functions. In other words, I suggest that for a biological system, the nature of time is specific and is an expression of the highly regulated integration. An internal physiological age reflects the irreversible course of a living organism towards death because of the irreversible course of physiological functions towards dysfunction, due to the irreversible changes in the regulatory processes. Following the works of Prigogine and his colleagues in physics, and more generally in the field of non-integrable dynamical systems (theorem of Poincaré-Misra), I have stated this problem in terms of the relationship between the macroscopic irreversibility of the functional organization and the basic mechanisms of regulation at the lowest "microscopic" level, i.e., the molecular, lowest level of organization. The neuron-neuron elementary functional interaction is proposed as an illustration of the method to define aging in the nervous system.

  13. Gel-free proteomic methodologies to study reversible cysteine oxidation and irreversible protein carbonyl formation.

    Science.gov (United States)

    Boronat, S; García-Santamarina, S; Hidalgo, E

    2015-05-01

    Oxidative modifications in proteins have been traditionally considered as hallmarks of damage by oxidative stress and aging. However, oxidants can generate a huge variety of reversible and irreversible modifications in amino acid side chains as well as in the protein backbones, and these post-translational modifications can contribute to the activation of signal transduction pathways, and also mediate the toxicity of oxidants. Among the reversible modifications, the most relevant ones are those arising from cysteine oxidation. Thus, formation of sulfenic acid or disulfide bonds is known to occur in many enzymes as part of their catalytic cycles, and it also participates in the activation of signaling cascades. Furthermore, these reversible modifications have been usually attributed with a protective role, since they may prevent the formation of irreversible damage by scavenging reactive oxygen species. Among irreversible modifications, protein carbonyl formation has been linked to damage and death, since it cannot be repaired and can lead to protein loss-of-function and to the formation of protein aggregates. This review is aimed at researchers interested on the biological consequences of oxidative stress, both at the level of signaling and toxicity. Here we are providing a concise overview on current mass-spectrometry-based methodologies to detect reversible cysteine oxidation and irreversible protein carbonyl formation in proteomes. We do not pretend to impose any of the different methodologies, but rather to provide an objective catwalk on published gel-free approaches to detect those two types of modifications, from a biologist's point of view.

  14. The Anesthetic Efficacy of the Intraosseous Injection in Irreversible Pulpitis.

    Science.gov (United States)

    1995-01-01

    The purpose of this study was to evaluate the anesthetic efficacy of an intraosseous injection in teeth diagnosed with irreversible pulpitis . Fifty...one healthy human subjects with symptomatic maxillary or mandibular posterior teeth diagnosed with irreversible pulpitis were used in this study. The

  15. Formation of Irreversible H-bonds in Cellulose Materials

    Science.gov (United States)

    Umesh P. Agarwal; Sally A. Ralph; Rick S. Reiner; Nicole M. Stark

    2015-01-01

    Understanding of formation of irreversible Hbonds in cellulose is important in a number of fields. For example, fields as diverse as pulp and paper and enzymatic saccharification of cellulose are affected. In the present investigation, the phenomenon of formation of irreversible H-bonds is studied in a variety of celluloses and under two different drying conditions....

  16. Combustion irreversibilities: Numerical simulation and analysis

    Science.gov (United States)

    Silva, Valter; Rouboa, Abel

    2012-08-01

    An exergy analysis was performed considering the combustion of methane and agro-industrial residues produced in Portugal (forest residues and vines pruning). Regarding that the irreversibilities of a thermodynamic process are path dependent, the combustion process was considering as resulting from different hypothetical paths each one characterized by four main sub-processes: reactant mixing, fuel oxidation, internal thermal energy exchange (heat transfer), and product mixing. The exergetic efficiency was computed using a zero dimensional model developed by using a Visual Basic home code. It was concluded that the exergy losses were mainly due to the internal thermal energy exchange sub-process. The exergy losses from this sub-process are higher when the reactants are preheated up to the ignition temperature without previous fuel oxidation. On the other hand, the global exergy destruction can be minored increasing the pressure, the reactants temperature and the oxygen content on the oxidant stream. This methodology allows the identification of the phenomena and processes that have larger exergy losses, the understanding of why these losses occur and how the exergy changes with the parameters associated to each system which is crucial to implement the syngas combustion from biomass products as a competitive technology.

  17. Structure of Irreversibly Adsorbed Star Polymers

    Science.gov (United States)

    Akgun, Bulent; Aykan, Meryem Seyma; Canavar, Seda; Satija, Sushil K.; Uhrig, David; Hong, Kunlun

    Formation of irreversibly adsorbed polymer chains on solid substrates have a huge impact on the wetting, glass transition, aging and polymer chain mobility in thin films. In recent years there has been many reports on the formation, kinetics and dynamics of these layers formed by linear homopolymers. Recent studies showed that by varying the number of polymer arms and arm molecular weight one can tune the glass transition temperature of thin polymer films. Using polymer architecture as a tool, the behavior of thin films can be tuned between the behavior of linear chains and soft colloids. We have studied the effect of polymer chain architecture on the structure of dead layer using X-ray reflectivity (XR) and atomic force microscopy. Layer thicknesses and densities of flattened and loosely adsorbed chains has been measured for linear, 4-arm, and 8-arm star polymers with identical total molecular weight as a function of substrate surface energy, annealing temperature and annealing time. Star polymers have been synthesized using anionic polymerization. XR measurements showed that 8-arm star PS molecules form the densest and the thickest dead layers among these three molecules.

  18. Irreversible energy flow in forced Vlasov dynamics

    KAUST Repository

    Plunk, Gabriel G.

    2014-10-01

    © EDP Sciences, Società Italiana di Fisica, Springer-Verlag. The recent paper of Plunk [G.G. Plunk, Phys. Plasmas 20, 032304 (2013)] considered the forced linear Vlasov equation as a model for the quasi-steady state of a single stable plasma wavenumber interacting with a bath of turbulent fluctuations. This approach gives some insight into possible energy flows without solving for nonlinear dynamics. The central result of the present work is that the forced linear Vlasov equation exhibits asymptotically zero (irreversible) dissipation to all orders under a detuning of the forcing frequency and the characteristic frequency associated with particle streaming. We first prove this by direct calculation, tracking energy flow in terms of certain exact conservation laws of the linear (collisionless) Vlasov equation. Then we analyze the steady-state solutions in detail using a weakly collisional Hermite-moment formulation, and compare with numerical solution. This leads to a detailed description of the Hermite energy spectrum, and a proof of no dissipation at all orders, complementing the collisionless Vlasov result.

  19. Prevention

    Science.gov (United States)

    ... Contact Aging & Health A to Z Find a Geriatrics Healthcare Professional Medications & Older Adults Making Your Wishes ... Prevention Hearing Loss Heart Attack High Blood Pressure Nutrition Osteoporosis Shingles Skin Cancer Related News Quitting Smoking, ...

  20. Irreversible work in a thermal medium with colored noise

    International Nuclear Information System (INIS)

    Ohkuma, Takahiro

    2009-01-01

    Irreversible work and its fluctuations in a classical system governed by non-Markovian stochastic dynamics are investigated. The production of irreversible work depends not only on the protocol of an operation but also on the details of the non-Markovian memory. We consider a generalized Langevin equation with a memory kernel and derive an expression for the irreversible work in the case of slow operations by carrying out an expansion of this memory kernel in the parameter representing the length of the memory. We apply our formulation to a harmonically trapped system and demonstrate the efficiency of a cycle by evaluating the irreversible work. It is found that a decrease in the irreversible work due to the memory effect can occur for an operation through which the trap is squeezed. The results for this harmonic system are verified exactly in the case that the memory kernel has exponential decay

  1. Irreversible work in a thermal medium with colored noise

    Science.gov (United States)

    Ohkuma, Takahiro

    2009-10-01

    Irreversible work and its fluctuations in a classical system governed by non-Markovian stochastic dynamics are investigated. The production of irreversible work depends not only on the protocol of an operation but also on the details of the non-Markovian memory. We consider a generalized Langevin equation with a memory kernel and derive an expression for the irreversible work in the case of slow operations by carrying out an expansion of this memory kernel in the parameter representing the length of the memory. We apply our formulation to a harmonically trapped system and demonstrate the efficiency of a cycle by evaluating the irreversible work. It is found that a decrease in the irreversible work due to the memory effect can occur for an operation through which the trap is squeezed. The results for this harmonic system are verified exactly in the case that the memory kernel has exponential decay.

  2. Roles of community organizations in improving cancer prevention instruction in schools.

    Science.gov (United States)

    Smith, D W; Zhang, J J; Colwell, B

    1998-02-01

    Health education can be an important factor in the development of appropriate health behaviors in children. Community agencies that have not traditionally supported school health education can be of significant influence in improving school health education. This study examined the relationships between the involvement of the American Cancer Society (ACS) in schools and the degree of implementation of cancer prevention curricula. School health specialists from 41 metropolitan school districts in Texas were surveyed regarding the coverage of topical areas related to cancer prevention, health instructional patterns in districts, and collaborative efforts with the ACS. Tobacco use was widely covered in all levels of schools (elementary, middle, and high school), as was nutrition. Cancer detection and the concepts of cancer as a disease received most extensive coverage in high schools, and there were no significant grade level differences regarding coverage of the risks of sun exposure. School personnel had little training and felt little district support for school health education. Most respondents felt that teachers saw the ACS primarily as a resource for cancer information and resources than as a collaborative partner in health education efforts. Community organizations can play three roles in supporting school health education. First, the organization must certainly provide disease-specific information (in this case, cancer). They must also promote comprehensive school health education in general. Lastly, the study illustrates that community organizations must act as advocates for broader change in schools by supporting the development of organizational capacity within schools and districts to implement quality school health education, enlisting community support for quality school health education, and supporting policy initiatives that strengthen school health education activities.

  3. Irreversible electroporation in a Swine lung model.

    Science.gov (United States)

    Dupuy, Damian E; Aswad, Bassam; Ng, Thomas

    2011-04-01

    This study was designed to evaluate the safety and tissue effects of IRE in a swine lung model. This study was approved by the institutional animal care committee. Nine anesthetized domestic swine underwent 15 percutaneous irreversible electroporation (IRE) lesion creations (6 with bipolar and 3 with 3-4 monopolar electrodes) under fluoroscopic guidance and with pancuronium neuromuscular blockade and EKG gating. IRE electrodes were placed into the central and middle third of the right mid and lower lobes in all animals. Postprocedure PA and lateral chest radiographs were obtained to evaluate for pneumothorax. Three animals were sacrificed at 2 weeks and six at 4 weeks. Animals underwent high-resolution CT scanning and PA and lateral radiographs 1 h before sacrifice. The treated lungs were removed en bloc, perfused with formalin, and sectioned. Gross pathologic and microscopic changes after standard hematoxylin and eosin staining were analyzed within the areas of IRE lesion creation. No significant adverse events were identified. CT showed focal areas of spiculated high density ranging in greatest diameter from 1.1-2.2 cm. On gross inspection of the sectioned lung, focal areas of tan discoloration and increased density were palpated in the areas of IRE. Histological analysis revealed focal areas of diffuse alveolar damage with fibrosis and inflammatory infiltration that respected the boundaries of the interlobular septae. No pathological difference could be discerned between the 2- and 4-week time points. The bronchioles and blood vessels within the areas of IRE were intact and did not show signs of tissue injury. IRE creates focal areas of diffuse alveolar damage without creating damage to the bronchioles or blood vessels. Short-term safety in a swine model appears to be satisfactory.

  4. Prevention

    DEFF Research Database (Denmark)

    Halken, S; Høst, A

    2001-01-01

    , breastfeeding should be encouraged for 4-6 months. In high-risk infants a documented extensively hydrolysed formula is recommended if exclusive breastfeeding is not possible for the first 4 months of life. There is no evidence for preventive dietary intervention neither during pregnancy nor lactation...... populations. These theories remain to be documented in proper, controlled and prospective studies. Breastfeeding and the late introduction of solid foods (>4 months) is associated with a reduced risk of food allergy, atopic dermatitis, and recurrent wheezing and asthma in early childhood. In all infants....... Preventive dietary restrictions after the age of 4-6 months are not scientifically documented....

  5. Pressure ulcer prevention in nursing homes: nurse descriptions of individual and organization level factors.

    Science.gov (United States)

    Dellefield, Mary Ellen; Magnabosco, Jennifer L

    2014-01-01

    Sustaining pressure ulcer prevention (PUP) in nursing homes has been difficult to achieve. Implementation science researchers suggest that identification of individual staff and organizational factors influencing current practices is essential to the development of an effective and customized plan to implement practice changes in a specific setting. A mixed methods approach was used to describe nurses' perceptions of individual and organization-level factors influencing performance of PUP in two Veterans Health Administration (VHA) nursing homes prior to implementation of a national VHA initiative on Hospital Acquired Pressure Ulcers (HAPUs). Individual interviews of 16 nursing staff were conducted. Individual factors influencing practice were a personal sense of responsibility to Veterans and belief in the effectiveness and importance of preventive measures. Organizational factors were existence of cooperative practices between nursing assistants and licensed nurses in assessing risk; teamwork, communication, and a commitment to Veterans' well-being. Integration and reinforcement of such factors in the development and maintenance of customized plans of PUP initiatives is recommended. Published by Mosby, Inc.

  6. Effectiveness of mixtures of vivianite and organic materials in preventing iron chlorosis in strawberry

    Energy Technology Data Exchange (ETDEWEB)

    Santiago, A. de; Carmona, E.; Quintero, J. M.; Delgado, A.

    2013-05-01

    Application of Fe salts with different organic matter sources has been demonstrated to be effective in preventing Fe deficiency chlorosis. The main objective of this work was to study the effectiveness of different Fe sources based on mixtures of humic substances or compost with vivianite in preventing this nutritional disorder in strawberry (Fragaria x ananassa cv Camarosa). To this end, a randomised block experiment involving four replications (3 plants per replication) and one factor (Fe source) was performed in a greenhouse using a calcareous growing medium. Iron sources studied were: (i) control without Fe, (ii) control with an effective Fe source in calcareous media (EDDHA-Fe, 0.1 g kg{sup -}1), (iii) vivianite (1 g kg{sup -}1 medium, which is the recommended rate), (iv) vivianite (1 g kg{sup -}1) + humic substances (HS 0.06 g kg{sup -}1), (v) vivianite (0.5 g kg{sup -}1) + HS (0.06 g kg{sup -}1) and (vi) a mixture of composted cork residue and vivianite at a 6:1 mass ratio (CORVIV) applied at a dose of 6 g kg-1 medium. All Fe sources were effective in increasing SPAD readings when compared with control without Fe. Treatments based on vivianite provided non-significantly different SPAD readings from that obtained with EDDHA-Fe. However, only CORVIV showed non-significantly different dry matter (DM) production, leaf area index, and total Fe content in the aerial part than EDDHA-Fe. Humic substances and vivianite at 1 g kg{sup -}1 increased DM yield in plants when compared with vivianite without HS, results with this last treatment being similar to those obtained with vivianite at 0.5 g kg–1 with HS. It can be concluded that studied sources of organic matter increased the efficiency of vivianite in preventing Fe chlorosis in strawberry, especially vivianite enriched cork compost which was as effective as EDDHA-Fe. (Author) 50 refs.

  7. From Prevention To Advance In Biomedicine: The Transfer Of Organs And Tissues

    Directory of Open Access Journals (Sweden)

    Gemma Flores-Pons

    2013-07-01

    Full Text Available Currently, within Western societies, we can see new practices that are at once reality and fiction as they unfold in the terrain of the possible, the imaginable and the optimum. In the present paper, we focus on the case of organ and tissues transfer to describe how those biomedical actants and practices involved are articulated, configuring it as an anticipatory process, namely as a constant movement attempting to bring mobile futures to the present. Drawing on an ethnographic study exploring the everyday activity of a Spanish transplant coordination team,, we begin by suggesting that donation gets inserted as an imperative in the increasingly individualized management of the citizens’ biological becomings. Secondly, we turn to how the articulation of the brain death diagnosis functions as an entity capable of creating coherence between the different temporalities produced in the organs and tissues transfer. Then, we show the optimization mechanisms that operate within the waiting lists materializing imagined futures. Finally, by way of describing the permanent latency in which the transplant coordination teams work, we give an account of how biomedicine is turning away from generating practices inserted in a logic of prevention to practices that obey a logic of preparation.

  8. Development of hybrid organic-inorganic optical coatings to prevent laser damage

    International Nuclear Information System (INIS)

    Compoint, Francois

    2015-01-01

    The optical devices (lents, mirrors, portholes...) that are set on the chains of the Laser Megajoule (LMJ) may be damaged by the high energy laser beam especially around the UV wavelength of 351 nm. The damages are micronic craters on the rear of the optics that grows exponentially after each laser shots. The study aims at developing some optical thin coatings on the rear of the optical substrates to prevent the growth of the damage by amortizing the laser shock wave, self-healing the craters that has appeared, or repairing the laser hole after the damage occurs. The thin coatings have been prepared by a sol-gel method by using silica precursor and a polydimethylsiloxane (PDMS) elastomer. The two species reacted together to get a hybrid organic-inorganic Ormosil (organically modified silica) material, by creating a silica network linked to the PDMS species with covalent and hydrogen bounds. The thin layers are obtained from the sol-gel solution by using a dip and spin coating method. The coatings have an excellent optical transmission around the UV (351 nm) wavelength. They also have some self-healing properties by using mechanical (viscoelastic) mechanism and chemical reversible hydrogen bounds action in the materials. The silica-PDMS coatings prove to be resistant to the laser beam at 351 nm, despite some optimizations that still need to be done to reach the sought laser damage threshold. (author) [fr

  9. Irreversible electroporation of human primary uveal melanoma in enucleated eyes.

    Directory of Open Access Journals (Sweden)

    Yossi Mandel

    Full Text Available Uveal melanoma (UM is the most common primary intraocular tumor in adults and is characterized by high rates of metastatic disease. Although brachytherapy is the most common globe-sparing treatment option for small- and medium-sized tumors, the treatment is associated with severe adverse reactions and does not lead to increased survival rates as compared to enucleation. The use of irreversible electroporation (IRE for tumor ablation has potential advantages in the treatment of tumors in complex organs such as the eye. Following previous theoretical work, herein we evaluate the use of IRE for uveal tumor ablation in human ex vivo eye model. Enucleated eyes of patients with uveal melanoma were treated with short electric pulses (50-100 µs, 1000-2000 V/cm using a customized electrode design. Tumor bioimpedance was measured before and after treatment and was followed by histopathological evaluation. We found that IRE caused tumor ablation characterized by cell membrane disruption while sparing the non-cellular sclera. Membrane disruption and loss of cellular capacitance were also associated with significant reduction in total tumor impedance and loss of impedance frequency dependence. The effect was more pronounced near the pulsing electrodes and was dependent on time from treatment to fixation. Future studies should further evaluate the potential of IRE as an alternative method of uveal melanoma treatment.

  10. Irreversible electroporation of human primary uveal melanoma in enucleated eyes.

    Science.gov (United States)

    Mandel, Yossi; Laufer, Shlomi; Belkin, Michael; Rubinsky, Boris; Pe'er, Jacob; Frenkel, Shahar

    2013-01-01

    Uveal melanoma (UM) is the most common primary intraocular tumor in adults and is characterized by high rates of metastatic disease. Although brachytherapy is the most common globe-sparing treatment option for small- and medium-sized tumors, the treatment is associated with severe adverse reactions and does not lead to increased survival rates as compared to enucleation. The use of irreversible electroporation (IRE) for tumor ablation has potential advantages in the treatment of tumors in complex organs such as the eye. Following previous theoretical work, herein we evaluate the use of IRE for uveal tumor ablation in human ex vivo eye model. Enucleated eyes of patients with uveal melanoma were treated with short electric pulses (50-100 µs, 1000-2000 V/cm) using a customized electrode design. Tumor bioimpedance was measured before and after treatment and was followed by histopathological evaluation. We found that IRE caused tumor ablation characterized by cell membrane disruption while sparing the non-cellular sclera. Membrane disruption and loss of cellular capacitance were also associated with significant reduction in total tumor impedance and loss of impedance frequency dependence. The effect was more pronounced near the pulsing electrodes and was dependent on time from treatment to fixation. Future studies should further evaluate the potential of IRE as an alternative method of uveal melanoma treatment.

  11. Investment Irreversibility and Precautionary Savings in General Equilibrium

    DEFF Research Database (Denmark)

    Ejarque, João

    Partial equilibrium models suggest that when uncertainty increases, agents increase savings and at the same time reduce investment in irreversible goods. This paper characterizes this problem in general equilibrium with technology shocks, additive output shocks and shocks to the marginal efficiency...... of investment. Uncertainty is associated with the variance of these random variables, and irreversibility is introduced by a non negativity constraint on investment. I find that irreversibility and changes in uncertainty can be responsible for sizeable movements in aggregate consumption and investment only...... if the shocks affect the marginal efficiency of investment. For all types of shocks, when concavity of the utility function is moderate or high, the irreversibility constraint never binds and the increase in variance has a negligible impact. Persistence in the shock process induces precautionary savings rather...

  12. Kinetic theory of nonequilibrium ensembles, irreversible thermodynamics, and generalized hydrodynamics

    CERN Document Server

    Eu, Byung Chan

    2016-01-01

    This book presents the fundamentals of irreversible thermodynamics for nonlinear transport processes in gases and liquids, as well as for generalized hydrodynamics extending the classical hydrodynamics of Navier, Stokes, Fourier, and Fick. Together with its companion volume on relativistic theories, it provides a comprehensive picture of the kinetic theory formulated from the viewpoint of nonequilibrium ensembles in both nonrelativistic and, in Vol. 2, relativistic contexts. Theories of macroscopic irreversible processes must strictly conform to the thermodynamic laws at every step and in all approximations that enter their derivation from the mechanical principles. Upholding this as the inviolable tenet, the author develops theories of irreversible transport processes in fluids (gases or liquids) on the basis of irreversible kinetic equations satisfying the H theorem. They apply regardless of whether the processes are near to or far removed from equilibrium, or whether they are linear or nonlinear with respe...

  13. Thermodynamic Analysis of an Irreversible Maisotsenko Reciprocating Brayton Cycle

    Directory of Open Access Journals (Sweden)

    Fuli Zhu

    2018-03-01

    Full Text Available An irreversible Maisotsenko reciprocating Brayton cycle (MRBC model is established using the finite time thermodynamic (FTT theory and taking the heat transfer loss (HTL, piston friction loss (PFL, and internal irreversible losses (IILs into consideration in this paper. A calculation flowchart of the power output (P and efficiency (η of the cycle is provided, and the effects of the mass flow rate (MFR of the injection of water to the cycle and some other design parameters on the performance of cycle are analyzed by detailed numerical examples. Furthermore, the superiority of irreversible MRBC is verified as the cycle and is compared with the traditional irreversible reciprocating Brayton cycle (RBC. The results can provide certain theoretical guiding significance for the optimal design of practical Maisotsenko reciprocating gas turbine plants.

  14. Maximum power and thermal efficiency of an irreversible power cycle

    Science.gov (United States)

    Ait-Ali, Mohand A.

    1995-10-01

    A simple Carnot-like irreversible power cycle is modeled with two isothermal and two adiabatic, irreversible processes. The generic source of internal irreversibility, deduced from the Clausius inequality, produces entropy at a rate proportional to the external heat conductance and the engine temperature ratio. This cycle is optimized for maximum power and maximum efficiency, and its performances compared to those of the endoreversible cycle, based on typical heat source and heat sink temperatures. Both cycles produce maximum power at the same engine temperature ratio, but the irreversible cycle prediction of maximum efficiency and heat conductance allocation between steam boiler and condenser, appear to be not only more realistic, but also more relevant to actual design considerations of power plants.

  15. Irreversibility and dissipation in finite-state automata

    International Nuclear Information System (INIS)

    Ganesh, Natesh; Anderson, Neal G.

    2013-01-01

    Irreversibility and dissipation in finite-state automata (FSA) are considered from a physical-information-theoretic perspective. A quantitative measure for the computational irreversibility of finite automata is introduced, and a fundamental lower bound on the average energy dissipated per state transition is obtained and expressed in terms of FSA irreversibility. The irreversibility measure and energy bound are germane to any realization of a deterministic automaton that faithfully registers abstract FSA states in distinguishable states of a physical system coupled to a thermal environment, and that evolves via a sequence of interactions with an external system holding a physical instantiation of a random input string. The central result, which is shown to follow from quantum dynamics and entropic inequalities alone, can be regarded as a generalization of Landauer's Principle applicable to FSAs and tailorable to specified automata. Application to a simple FSA is illustrated.

  16. General thermodynamic performance of irreversible absorption heat pump

    International Nuclear Information System (INIS)

    Zhao Xiling; Fu Lin; Zhang Shigang

    2011-01-01

    The absorption heat pump (AHP) was studied with thermodynamics. A four reservoirs model of absorption heat pump was established considering the heat resistance, heat leak and the internal irreversibility. The reasonable working regions, the performance effects of irreversibility, heat leak and the correlation of four components were studied. When studying the effects of internal irreversibility, two internal irreversibility parameters (I he for generator-absorber assembly and I re for evaporator-condenser assembly) were introduced to distinguish the different effects. When studying the heat transfer relations of four components, a universal relationship between the main parameters were deduced. The results which have more realized meaning show that, the reduction of the friction, heat loss, and internal dissipations of the evaporator-condenser assembly are more important than its reduction of generator-absorber assembly, and lessening the heat leak of generator are more important than its reduction of other components to improve the AHP performance.

  17. On vectorial irreversible processes in homogeneous isotropic cosmological models

    International Nuclear Information System (INIS)

    Meier, W.

    1990-01-01

    In a given Friedman metric in the framework of usual thermodynamics of irreversible processes, the general relativistic diffusion equation is derived. To give solutions to the equation for special assumptions, the results in a Schroedinger paper are used. (author)

  18. Irreversible pulpitis and achieving profound anesthesia: Complexities and managements

    Science.gov (United States)

    Modaresi, Jalil; Davoudi, Amin; Badrian, Hamid; Sabzian, Roya

    2016-01-01

    Dental pain management is one of the most critical aspects of modern dentistry. Irreversible pulpitis and further root canal therapy might cause an untolerated pain to the patients. The improvements in anesthetic agents and techniques were one of the advantages of studying nerve biology and stimulation. This article tried to overview of the nerve activities in inflammatory environments or induced pain. Furthermore, the proper advises, and supplementary techniques were reviewed for better pain management of irreversible pulpitis. PMID:26957681

  19. Anisotropic shift of the irreversibility line by neutron irradiation

    International Nuclear Information System (INIS)

    Sauerzopf, F.M.; Wiesinger, H.P.; Weber, H.W.; Crabtree, G.W.; Frischherz, M.C.; Kirk, M.A.

    1991-09-01

    The irreversibility line of high-T c superconductors is shifted considerably by irradiating the material with fast neutrons. The anisotropic and non-monotonous shift is qualitatively explained by a simple model based on an interaction between three pinning mechanisms, the intrinsic pinning by the ab-planes, the weak pinning by the pre-irradiation defect structure, and strong pinning by neutron induced defect cascades. A correlation between the cascade density and the position of the irreversibility line is observed

  20. Towards irreversibility with a finite bath of oscillators

    Energy Technology Data Exchange (ETDEWEB)

    De São José, A.N. [Departamento de Engenharia Elétrica, Centro Federal de Educação Tecnológica de Minas Gerais, 30510-000 Belo Horizonte, MG (Brazil); Dias, P.M. [Programa de Pós-Graduação em Modelagem Matemática e Computacional, Centro Federal de Educação Tecnológica de Minas Gerais, 30510-000 Belo Horizonte, MG (Brazil); Bosco de Magalhães, A.R., E-mail: arthur.magalhaes@pq.cnpq.br [Programa de Pós-Graduação em Modelagem Matemática e Computacional, Centro Federal de Educação Tecnológica de Minas Gerais, 30510-000 Belo Horizonte, MG (Brazil); Departamento de Física e Matemática, Centro Federal de Educação Tecnológica de Minas Gerais, 30510-000 Belo Horizonte, MG (Brazil); and others

    2012-12-03

    We investigate the routes by which a bath composed of a finite number of oscillators at zero temperature approaches the induction of dissipation when it nears the usual limit of dense spectrum spread in an infinite interval. It is shown that, when this limit is taken, different distributions of environment frequencies can lead to the same irreversible evolution. However, when we move away from it, the dynamics departs from irreversibility in qualitatively different manners.

  1. Preventive palliation in the elderly - Organizing health camps for the rural aged

    Directory of Open Access Journals (Sweden)

    Abhijit Dam

    2010-01-01

    Full Text Available Most of the needs of elders for support and assistance in the later stages of life are fulfilled by informal helpers. The position of a large number of older persons has become vulnerable due to which it cannot be taken for granted that their children will be able to look after them when they need care in old age, specially in view of the longer life span implying an extended period of dependency and higher costs to meet health and other needs. The condition of the rural elderly is even more pitiable, contrary to our beliefs, as availability, affordability and accessibility to medicare facilities are poor. We undertook the task of organizing a health camp in a rural set-up with the idea of implementing our concept of "preventive palliation" in which excellent palliative care was coupled with a pinch of prevention, like routine checks of blood pressure, routine physical check-ups, etc, so that any aberration can be detected early and necessary rectification measures can be implemented. These periods of routine check-ups can also be used to assess the psycho-social, cultural and emotional problems, if any. Such an approach, say every monthly, gives the elderly something to look forward to and ensures a high degree of customer satisfaction and greatly reduces the burden on the current health system. The challenges faced and the data obtained from this study were shocking. The elderly living in rural areas of the tribal state of Jharkhand suffer from poor physical and mental health, a factor which was rather unexpected in the Indian cultural system in the rural setting. Simple strategies like implementing routine health check ups with provision of "nutritious meal program" can go a long way in mitigating these problems in a cost-effective and simple manner. To make the government-based programs accessible and available to the end-users, participation of local bodies like NGOs is mandatory. Preventive palliation, a concept introduced by Kosish, is

  2. Stress Prevention@Work: a study protocol for the evaluation of a multifaceted integral stress prevention strategy to prevent employee stress in a healthcare organization: a cluster controlled trial.

    Science.gov (United States)

    Hoek, Rianne J A; Havermans, Bo M; Houtman, Irene L D; Brouwers, Evelien P M; Heerkens, Yvonne F; Zijlstra-Vlasveld, Moniek C; Anema, Johannes R; van der Beek, Allard J; Boot, Cécile R L

    2017-07-17

    Adequate implementation of work-related stress management interventions can reduce or prevent work-related stress and sick leave in organizations. We developed a multifaceted integral stress-prevention strategy for organizations from several sectors that includes a digital platform and collaborative learning network. The digital platform contains a stepwise protocol to implement work-related stress-management interventions. It includes stress screeners, interventions and intervention providers to facilitate access to and the selection of matching work-related stress-management interventions. The collaborative learning network, including stakeholders from various organizations, plans meetings focussing on an exchange of experiences and good practices among organizations for the implementation of stress prevention measures. This paper describes the design of an integral stress-prevention strategy, Stress Prevention@Work, and the protocol for the evaluation of: 1) the effects of the strategy on perceived stress and work-related outcomes, and 2) the barriers and facilitators for implementation of the strategy. The effectiveness of Stress Prevention@Work will be evaluated in a cluster controlled trial, in a large healthcare organization in the Netherlands, at six and 12 months. An independent researcher will match teams on working conditions and size and allocate the teams to the intervention or control group. Teams in the intervention group will be offered Stress Prevention@Work. For each intervention team, one employee is responsible for applying the strategy within his/her team using the digital platform and visiting the collaborative learning network. Using a waiting list design, the control group will be given access to the strategy after 12 months. The primary outcome is the employees' perceived stress measured by the stress subscale of the Depression, Anxiety, and Stress Scale (DASS-21). Secondary outcome measures are job demands, job resources and the number

  3. Stress Prevention@Work: a study protocol for the evaluation of a multifaceted integral stress prevention strategy to prevent employee stress in a healthcare organization: a cluster controlled trial

    Directory of Open Access Journals (Sweden)

    Rianne J. A. Hoek

    2017-07-01

    Full Text Available Abstract Background Adequate implementation of work-related stress management interventions can reduce or prevent work-related stress and sick leave in organizations. We developed a multifaceted integral stress-prevention strategy for organizations from several sectors that includes a digital platform and collaborative learning network. The digital platform contains a stepwise protocol to implement work-related stress-management interventions. It includes stress screeners, interventions and intervention providers to facilitate access to and the selection of matching work-related stress-management interventions. The collaborative learning network, including stakeholders from various organizations, plans meetings focussing on an exchange of experiences and good practices among organizations for the implementation of stress prevention measures. This paper describes the design of an integral stress-prevention strategy, Stress Prevention@Work, and the protocol for the evaluation of: 1 the effects of the strategy on perceived stress and work-related outcomes, and 2 the barriers and facilitators for implementation of the strategy. Methods The effectiveness of Stress Prevention@Work will be evaluated in a cluster controlled trial, in a large healthcare organization in the Netherlands, at six and 12 months. An independent researcher will match teams on working conditions and size and allocate the teams to the intervention or control group. Teams in the intervention group will be offered Stress Prevention@Work. For each intervention team, one employee is responsible for applying the strategy within his/her team using the digital platform and visiting the collaborative learning network. Using a waiting list design, the control group will be given access to the strategy after 12 months. The primary outcome is the employees’ perceived stress measured by the stress subscale of the Depression, Anxiety, and Stress Scale (DASS-21. Secondary outcome measures

  4. [Fourth update of the guidelines on determination of irreversible brain death. Procedural course and amendments].

    Science.gov (United States)

    Tonn, J-C

    2016-02-01

    In 2015 the fourth update of the directive for the determination of definitely irreversible loss of complete function of the cerebrum, cerebellum and brainstem was passed and came into force. This was preceded by several hearings of all professional societies and associations involved as well as a 2-year advisory process of an interdisciplinary working party. The directive is intended to determine irreversible brain death in the field of intensive care medicine and is independent of individual decisions about organ donation. Not only an update based on scientific data but also a clarification of the several procedures and a clear definition of the medical qualifications required were worked out. Furthermore, the technical procedures computed tomography (CT) angiography and duplex sonography were adopted for the diagnosis of cerebral circulatory arrest. The new directive including comprehensive explanatory notes was approved by the German Federal Ministry of Health and published by the German Medical Council (Bundesärztekammer).

  5. The IAEA Establishes Partnerships with International Organizations to Prevent Malnutrition in Children and Older People

    International Nuclear Information System (INIS)

    Yusuf, Omar

    2014-01-01

    The period from conception to 2 years of age — the first thousand days of a child’s life — represents a critical window of opportunity for avoiding health risks later in life. The assessment of growth during this crucial period of early vulnerability has traditionally been largely based on anthropometric measurements such as body weight and length, with less attention to the quality of growth and the relative partitioning of nutrients to fat-free mass or fat mass. However, now, the amount and distribution of body fat and the amount and composition of lean mass are understood to be very important for the long term health prospects of infants and children. Isotope techniques can be used to measure body composition with a high degree of accuracy. This provides governments with key data to enable them to make decisions about national nutrition interventions on the basis of evidence. The IAEA is working in partnership with international organizations around the world to reduce malnutrition, and, consequently, to alleviate the multitude of preventable diseases caused by poor nutrition

  6. Attribution of irreversible loss to anthropogenic climate change

    Science.gov (United States)

    Huggel, Christian; Bresch, David; Hansen, Gerrit; James, Rachel; Mechler, Reinhard; Stone, Dáithí; Wallimann-Helmer, Ivo

    2016-04-01

    The Paris Agreement (2015) under the UNFCCC has anchored loss and damage in a separate article which specifies that understanding and support should be enhanced in areas addressing loss and damage such as early warning, preparedness, insurance and resilience. Irreversible loss is a special category under loss and damage but there is still missing clarity over what irreversible loss actually includes. Many negative impacts of climate change may be handled or mitigated by existing risk management, reduction and absorption approaches. Irreversible loss, however, is thought to be insufficiently addressed by risk management. Therefore, countries potentially or actually affected by irreversible loss are calling for other measures such as compensation, which however is highly contested in international climate policy. In Paris (2015) a decision was adopted that loss and damage as defined in the respective article of the agreement does not involve compensation and liability. Nevertheless, it is likely that some sort of mechanism will eventually need to come into play for irreversible loss due to anthropogenic climate change, which might involve compensation, other forms of non-monetary reparation, or transformation. Furthermore, climate litigation has increasingly been attempted to address negative effects of climate change. In this context, attribution is important to understand the drivers of change, what counts as irreversible loss due to climate change, and, possibly, who or what is responsible. Here we approach this issue by applying a detection and attribution perspective on irreversible loss. We first analyze detected climate change impacts as assessed in the IPCC Fifth Assessment Report. We distinguish between irreversible loss in physical, biological and human systems, and accordingly identify the following candidates of irreversible loss in these systems: loss of glaciers and ice sheets, loss of subsurface ice (permafrost) and related loss of lake systems; loss

  7. The incidence of mechanical allodynia in patients with irreversible pulpitis.

    Science.gov (United States)

    Owatz, Christopher B; Khan, Asma A; Schindler, William G; Schwartz, Scott A; Keiser, Karl; Hargreaves, Kenneth M

    2007-05-01

    The mechanisms of odontogenic pain are complex and incompletely understood. Cases of irreversible pulpitis are thought to represent a localized inflammatory response to bacterial challenge in dental pulp tissue. The presenting symptoms are classically defined by exaggerated painful episodes to thermal stimuli that may linger after cessation of the stimulus. However, the associated incidence of mechanical allodynia, defined as reduced mechanical pain threshold to masticatory forces, has not been characterized. This study evaluated pain intensity ratings and the presence of mechanical allodynia reported by 993 consecutive dental patients presenting for tooth extraction in a community health center. After clinical and radiographic examinations, the pulpal/periradicular diagnostic categories were normal pulp/normal periradicular (n=792 patients), irreversible pulpitis/normal periradicular (n=86), or irreversible pulpitis/acute periradicular periodontitis (n=115). The rank order for the mean values of pain intensity ratings was irreversible pulpitis/acute periradicular periodontitis > irreversible pulpitis/normal periradicular > normal/normal (pirreversible pulpitis was 57.2%, indicating that periradicular mechanical allodynia contributes to early stages of odontogenic pain because of inflammation of vital pulpal tissue.

  8. Irreversible climate change due to carbon dioxide emissions.

    Science.gov (United States)

    Solomon, Susan; Plattner, Gian-Kasper; Knutti, Reto; Friedlingstein, Pierre

    2009-02-10

    The severity of damaging human-induced climate change depends not only on the magnitude of the change but also on the potential for irreversibility. This paper shows that the climate change that takes place due to increases in carbon dioxide concentration is largely irreversible for 1,000 years after emissions stop. Following cessation of emissions, removal of atmospheric carbon dioxide decreases radiative forcing, but is largely compensated by slower loss of heat to the ocean, so that atmospheric temperatures do not drop significantly for at least 1,000 years. Among illustrative irreversible impacts that should be expected if atmospheric carbon dioxide concentrations increase from current levels near 385 parts per million by volume (ppmv) to a peak of 450-600 ppmv over the coming century are irreversible dry-season rainfall reductions in several regions comparable to those of the "dust bowl" era and inexorable sea level rise. Thermal expansion of the warming ocean provides a conservative lower limit to irreversible global average sea level rise of at least 0.4-1.0 m if 21st century CO(2) concentrations exceed 600 ppmv and 0.6-1.9 m for peak CO(2) concentrations exceeding approximately 1,000 ppmv. Additional contributions from glaciers and ice sheet contributions to future sea level rise are uncertain but may equal or exceed several meters over the next millennium or longer.

  9. How externalities impact an evaluation of strategies to prevent antimicrobial resistance in health care organizations

    Directory of Open Access Journals (Sweden)

    Jenine R. Leal

    2017-06-01

    Full Text Available Abstract Background The rates of antimicrobial-resistant organisms (ARO continue to increase for both hospitalized and community patients. Few resources have been allocated to reduce the spread of resistance on global, national and local levels, in part because the broader economic impact of antimicrobial resistance (i.e. the externality is not fully considered when determining how much to invest to prevent AROs, including strategies to contain antimicrobial resistance, such as antimicrobial stewardship programs. To determine how best to measure and incorporate the impact of externalities associated with the antimicrobial resistance when making resource allocation decisions aimed to reduce antimicrobial resistance within healthcare facilities, we reviewed the literature to identify publications which 1 described the externalities of antimicrobial resistance, 2 described approaches to quantifying the externalities associated with antimicrobial resistance or 3 described macro-level policy options to consider the impact of externalities. Medline was reviewed to identify published studies up to September 2016. Main body An externality is a cost or a benefit associated with one person’s activity that impacts others who did not choose to incur that cost or benefit. We did not identify a well-accepted method of accurately quantifying the externality associated with antimicrobial resistance. We did identify three main methods that have gained popularity to try to take into account the externalities of antimicrobial resistance, including regulation, charges or taxes on the use of antimicrobials, and the right to trade permits or licenses for antimicrobial use. To our knowledge, regulating use of antimicrobials is the only strategy currently being used by health care systems to reduce antimicrobial use, and thereby reduce AROs. To justify expenditures on programs that reduce AROs (i.e. to formally incorporate the impact of the negative externality of

  10. Irreversible collective migration of cyanobacteria in eutrophic conditions.

    Directory of Open Access Journals (Sweden)

    Julien Dervaux

    Full Text Available In response to natural or anthropocentric pollutions coupled to global climate changes, microorganisms from aquatic environments can suddenly accumulate on water surface. These dense suspensions, known as blooms, are harmful to ecosystems and significantly degrade the quality of water resources. In order to determine the physico-chemical parameters involved in their formation and quantitatively predict their appearance, we successfully reproduced irreversible cyanobacterial blooms in vitro. By combining chemical, biochemical and hydrodynamic evidences, we identify a mechanism, unrelated to the presence of internal gas vesicles, allowing the sudden collective upward migration in test tubes of several cyanobacterial strains (Microcystis aeruginosa PCC 7005, Microcystis aeruginosa PCC 7806 and Synechocystis sp. PCC 6803. The final state consists in a foamy layer of biomass at the air-liquid interface, in which micro-organisms remain alive for weeks, the medium lying below being almost completely depleted of cyanobacteria. These "laboratory blooms" start with the aggregation of cells at high ionic force in cyanobacterial strains that produce anionic extracellular polymeric substances (EPS. Under appropriate conditions of nutrients and light intensity, the high photosynthetic activity within cell clusters leads the dissolved oxygen (DO to supersaturate and to nucleate into bubbles. Trapped within the EPS, these bubbles grow until their buoyancy pulls the biomass towards the free surface. By investigating a wide range of spatially homogeneous environmental conditions (illumination, salinity, cell and nutrient concentration we identify species-dependent thresholds and timescales for bloom formation. We conclude on the relevance of such results for cyanobacterial bloom formation in the environment and we propose an efficient method for biomass harvesting in bioreactors.

  11. Dual chamber stent prevents organ malperfusion in a model of donation after cardiac death.

    Science.gov (United States)

    Tillman, Bryan W; Chun, Youngjae; Cho, Sung Kwon; Chen, Yanfei; Liang, Nathan; Maul, Timothy; Demetris, Anthony; Gu, Xinzhu; Wagner, William R; Tevar, Amit D

    2016-10-01

    The paradigm for donation after cardiac death subjects donor organs to ischemic injury. A dual-chamber organ perfusion stent would maintain organ perfusion without affecting natural cardiac death. A center lumen allows uninterrupted cardiac blood flow, while an external chamber delivers oxygenated blood to the visceral vessels. A prototype organ perfusion stent was constructed from commercial stents. In a porcine model, the organ perfusion stent was deployed, followed by a simulated agonal period. Oxygenated blood perfused the external stent chamber. Organ perfusion was compared between controls (n = 3) and organ perfusion stent (n = 6). Finally, a custom, nitinol, dual chamber organ perfusion stent was fabricated using a retrievable "petal and stem" design. Endovascular organ perfusion stent deployment achieved visceral isolation without adverse impact on cardiac parameters. Visceral oxygen delivery was 4.8-fold greater compared with controls. During the agonal period, organs in organ perfusion stent-treated animals appeared well perfused in contrast with the malperfused controls. A custom nitinol and polyurethane organ perfusion stent was recaptured easily with simple sheath advancement. An organ perfusion stent maintained organ perfusion during the agonal phase in a porcine model of donation after cardiac death organ donation without adversely affecting cardiac function. Ultimately, the custom retrievable design of this study may help resolve the critical shortage of donor organs for transplant. Copyright © 2016 Elsevier Inc. All rights reserved.

  12. Irreversibility analysis in the process of solar distillation

    Science.gov (United States)

    Chávez, S.; Terres, H.; Lizardi, A.; López, R.; Lara, A.

    2017-01-01

    In this work an irreversibility analysis for the thermal process of solar distillation of three different substances is presented, for which it employs a solar still of a slope where three experimental tests with 5.5 L of brine, river water and MgCl2 were performed. Temperature data principally in the glass cover, absorber plate, fluid, environment and the incident solar radiation on the device were obtained. With measurements of temperature, solar radiation and exergetic balance, irreversibilities are found on the device. The results show that the highest values of irreversibilities are concentrated in the absorber plate with an average of 321 W, 342 W and 276 W, followed by the cover glass with an average of 75.8 W, 80.4 W and 86.7 W and finally the fluid with 15.3 W, 15.9 W and 16 W, for 5.5 L of brine, river water and MgCl2.

  13. Reversible and Irreversible Binding of Nanoparticles to Polymeric Surfaces

    Directory of Open Access Journals (Sweden)

    Wolfgang H. Binder

    2009-01-01

    Full Text Available Reversible and irreversible binding of CdSe-nanoparticles and nanorods to polymeric surfaces via a strong, multiple hydrogen bond (= Hamilton-receptor/barbituric acid is described. Based on ROMP-copolymers, the supramolecular interaction on a thin polymer film is controlled by living polymerization methods, attaching the Hamilton-receptor in various architectures, and concentrations. Strong binding is observed with CdSe-nanoparticles and CdSe-nanorods, whose surfaces are equipped with matching barbituric acid-moieties. Addition of polar solvents, able to break the hydrogen bonds leads to the detachment of the nanoparticles from the polymeric film. Irreversible binding is observed if an azide/alkine-“click”-reaction is conducted after supramolecular recognition of the nanoparticles on the polymeric surface. Thus reversible or irreversible attachment of the nanosized objects can be achieved.

  14. Hydraulically irreversible fouling on ceramic MF/UF membranes: comparison of fouling indices, foulant composition and irreversible pore narrowing

    KAUST Repository

    Shang, Ran

    2015-05-06

    The application of ceramic membranes in water treatment is becoming increasing attractive because of their long life time and excellent chemical, mechanical and thermal stability. However, fouling of ceramic membranes, especially hydraulically irreversible fouling, is still a critical aspect affecting the operational cost and energy consumption in water treatment plants. In this study, four ceramic membranes with pore sizes or molecular weight cut-off (MWCO) of 0.20 μm, 0.14 μm, 300 kDa and 50 kDa were compared during natural surface water filtration with respect to hydraulically irreversible fouling index (HIFI), foulant composition and narrowing of pore size due to the irreversible fouling. Our results showed that the hydraulically irreversible fouling index (HIFI) was proportional to the membrane pore size (r2=0.89) when the same feed water was filtrated. The UF membranes showed lower HIFI values than the MF membranes. Pore narrowing (internal fouling) was found to be a main fouling pattern of the hydraulically irreversible fouling. The internal fouling was caused by monolayer adsorption of foulants with different sizes that is dependent on the size of the membrane pore.

  15. The thermomechanics of nonlinear irreversible behaviors an introduction

    CERN Document Server

    Maugin, Gérard A

    1999-01-01

    In this invaluable book, macroscopic irreversible thermodynamics is presented in its realm and its splendor by appealing to the notion of internal variables of state. This applies to both fluids and solids with or without microstructures of mechanical or electromagnetic origin. This unmatched richness of essentially nonlinear behaviors is the result of the use of modern mathematical techniques such as convex analysis in a clear-cut framework which allows one to put under the umbrella of "irreversible thermodynamics" behaviors which until now have been commonly considered either not easily cove

  16. A new approach to irreversibility in deep inelastic collisions

    International Nuclear Information System (INIS)

    Nemes, M.C.

    1982-01-01

    We use concepts of statistical mechanics to discuss the irreversible character of the experimental data in deep inelastic collisions. A definition of irreversibility proposed by Ruch permits a unified overview on current theories which describe these reactions. An information theoretical analysis of the data leads to a Fokker-Planck equation for the collective variables (excitation energy, charge and mass). The concept of mixing distance can serve as a quantitative measure to characterize the 'approach to equilibrium'. We apply it to the brownian motion as an illustration and also to the phenomenological analysis of deep inelastic scattering data with interesting results. (orig.)

  17. How is selective prevention of cardiometabolic diseases organized in the EU member states?

    NARCIS (Netherlands)

    Waard, A.K. de; Korevaar, J.; Hollander, M.; Wit, N. de; Lionis, C.; Thilsing, T.; Carlsson, A.; Seifert, B.; Schellevis, F.

    2016-01-01

    Background and Aim: There is an urgent need for strategies to identify citizens at high risk of cardiometabolic disease (CMD) (cardiovascular disease, diabetes mellitus and chronic renal failure) and to develop and implement interventions to prevent or delay the onset of CMD. Prevention in a defined

  18. How to engage small retail businesses in workplace violence prevention: Perspectives from small businesses and influential organizations.

    Science.gov (United States)

    Bruening, Rebecca A; Strazza, Karen; Nocera, Maryalice; Peek-Asa, Corinne; Casteel, Carri

    2015-06-01

    Small retail businesses experience high robbery and violent crime rates leading to injury and death. Workplace violence prevention programs (WVPP) based on Crime Prevention Through Environmental Design reduce this risk, but low small business participation limits their effectiveness. Recent dissemination models of occupational safety and health information recommend collaborating with an intermediary organization to engage small businesses. Qualitative interviews with 70 small business operators and 32 representatives of organizations with small business influence were conducted to identify factors and recommendations for improving dissemination of a WVPP. Both study groups recommended promoting WVPPs through personal contacts but differed on other promotion methods and the type of influential groups to target. Small business operators indicated few connections to formal business networks. Dissemination of WVPPs to small businesses may require models inclusive of influential individuals (e.g., respected business owners) as intermediaries to reach small businesses with few formal connections. © 2015 Wiley Periodicals, Inc.

  19. International organizations and NGOs: an example of international collaboration to improve women's health by preventing unsafe abortion.

    Science.gov (United States)

    Zaidi, Shahida; Hassan, Ezzeldin Osman; Hodorogea, Stelian; Leke, Robert J I; Távara, Luis; de Gil, Marina Padilla

    2010-07-01

    International collaboration with organizations and agencies is a basic requirement for the success of the FIGO Initiative for the Prevention of Unsafe Abortion and its Consequences. Many activities being carried out by the organizations form a part of the plans of action of all countries participating in the Initiative. It was, therefore, not difficult to obtain their collaboration in implementing the plans of action. The many ways in which they have collaborated and continue to do so are described in this article. This collaboration has saved time, avoided duplication of effort, and has also satisfied the Accra Agenda of Action by reducing fragmentation of funding. It has already contributed toward preventing unsafe abortion and reducing abortion-related maternal deaths and morbidities, and is expected to contribute even more significantly in the coming months and years. (c) 2010 International Federation of Gynecology and Obstetrics. Published by Elsevier Ireland Ltd. All rights reserved.

  20. A PILOT STUDY OF HYDROXYUREA TO PREVENT CHRONIC ORGAN DAMAGE IN YOUNG CHILDREN WITH SICKLE CELL ANEMIA

    Science.gov (United States)

    Thornburg, Courtney D.; Dixon, Natalia; Burgett, Shelly; Mortier, Nicole A.; Schultz, William H.; Zimmerman, Sherri A.; Bonner, Melanie; Hardy, Kristina K.; Calatroni, Agustin; Ware, Russell E.

    2016-01-01

    Background Hydroxyurea improves laboratory parameters and prevents acute clinical complications of sickle cell anemia (SCA) in children and adults, but its effects on organ function remain incompletely defined. Methods To assess the safety and efficacy of hydroxyurea in young children with SCA and to prospectively assess kidney and brain function, 14 young children (mean age 35 months) received hydroxyurea at a mean maximum tolerated dose (MTD) of 28 mg/kg/day. Results After a mean of 25 months, expected laboratory effects included significant increases in hemoglobin, MCV and %HbF along with significant decreases in reticulocytes, absolute neutrophil count, and bilirubin. There was no significant increase in glomerular filtration rate by DTPA clearance or Schwartz estimate. Mean transcranial Doppler (TCD) velocity changes were −25.6 cm/sec (phydroxyurea at MTD is well-tolerated by both children and families, and may prevent chronic organ damage in young children with SCA. PMID:19061213

  1. [Evaluation of the organization of health services as a strategy for the prevention and control of visceral leishmaniasis].

    Science.gov (United States)

    Barbosa, Miriam Nogueira; Guimarães, Eliete Albano de Azevedo; Luz, Zélia Maria Profeta da

    2016-01-01

    to evaluate the organization of health services as a strategy for the prevention and control of visceral leishmaniasis (VL) in Ribeirão das Neves, Minas Gerais, Brazil, from 2010 to 2012. this was a case study evaluation of the degree of implementation of a strategy for the integration of health care services, control of zoonosis and epidemiological surveillance; it consisted of observing the work process, interviewing health professionals and analysing secondary data from information systems. implementation was partially adequate (84%); in terms of structure, the human resources component had the worst evaluation (64%) whilst in terms of work process, evaluation was 80% for reorganization of care and 77% for surveillance; in the period 2010-2012 there was a 20% increase in reported cases of VL and a 20% reduction in the time interval between reporting a case and starting treatment. the strategy contributed to the improvement of the organization of VL prevention and control actions.

  2. What Nigerian ophthalmologists do for their irreversibly blind patients

    African Journals Online (AJOL)

    The diagnosis of irreversible blindness (IB) is a traumatic one for both the ophthalmologist and the patient, because of the finality of the patient's loss of sight. There are supportive measures that an ophthalmologist could provide to ensure a dignified and productive life for the blind patient. This communication examines the ...

  3. Parametric optimum analysis of an irreversible Ericsson cryogenic ...

    Indian Academy of Sciences (India)

    An irreversible model of an Ericsson cryogenic refrigeration cycle working with an ideal Fermi gas is established, which is composed of two isothermal and two ... University, Xiamen 361005, People's Republic of China; Department of Physics, Quanzhou Normal University, Quanzhou 362000, People's Republic of China ...

  4. Minimum energy dissipation required for a logically irreversible operation

    Science.gov (United States)

    Takeuchi, Naoki; Yoshikawa, Nobuyuki

    2018-01-01

    According to Landauer's principle, the minimum heat emission required for computing is linked to logical entropy, or logical reversibility. The validity of Landauer's principle has been investigated for several decades and was finally demonstrated in recent experiments by showing that the minimum heat emission is associated with the reduction in logical entropy during a logically irreversible operation. Although the relationship between minimum heat emission and logical reversibility is being revealed, it is not clear how much free energy is required to be dissipated for a logically irreversible operation. In the present study, in order to reveal the connection between logical reversibility and free energy dissipation, we numerically demonstrated logically irreversible protocols using adiabatic superconductor logic. The calculation results of work during the protocol showed that, while the minimum heat emission conforms to Landauer's principle, the free energy dissipation can be arbitrarily reduced by performing the protocol quasistatically. The above results show that logical reversibility is not associated with thermodynamic reversibility, and that heat is not only emitted from logic devices but also absorbed by logic devices. We also formulated the heat emission from adiabatic superconductor logic during a logically irreversible operation at a finite operation speed.

  5. Exergetic efficiency optimization for an irreversible heat pump ...

    Indian Academy of Sciences (India)

    The irreversibilities considered in the system include heat resistance losses in the hot- and cold-side heat exchangers and non-isentropic losses in the compression and expansion processes. The analytical formulas of the heating load, coefficient of performance (COP) and exergetic efficiency for the heat pumps are derived ...

  6. Exergetic efficiency optimization for an irreversible heat pump ...

    Indian Academy of Sciences (India)

    This paper deals with the performance analysis and optimization for irreversible heat pumps working on reversed Brayton cycle with constant-temperature heat reservoirs by taking exergetic efficiency as the optimization objective combining exergy concept with finite-time thermodynamics (FTT). Exergetic efficiency is ...

  7. Profit rate performance optimization for a generalized irreversible ...

    Indian Academy of Sciences (India)

    The operation of the generalized irreversible combined refrigeration cycle is viewed as a production process with exergy as its output. The performance optimization of the cycle is performed by taking profit as the objective. The optimal profit rate, optimal COP (coefficient of performance), as well as the relation between the ...

  8. Profit rate performance optimization for a generalized irreversible ...

    Indian Academy of Sciences (India)

    engineering economic optimization to evaluate and optimize the design and performance of energy systems is ... paper is to study the finite time exergoeconomic performance of the generalized irreversible combined refrigeration cycle. ..... qualitative differences are as following: when 0 ≤ ψ2/ψ1 ≤ 0·033, the curves of π − ε.

  9. Parametric optimum analysis of an irreversible Ericsson cryogenic ...

    Indian Academy of Sciences (India)

    on the heat-transfer law and the heat conductances. It is often assumed that heat. 780. Pramana – J. ... an irreversible Fermi–. Ericsson refrigeration cycle. transfer obeys Newton's law [25], i.e., ...... [20] P K Pathria, Statistical mechanics 2nd edition (Elsevier Pvt Ltd, Singapore, 1996). [21] K Huang, Statistical mechanics 2nd ...

  10. Sector of West Antarctic Ice Sheet in "Irreversible Retreat"

    Science.gov (United States)

    Showstack, Randy

    2014-05-01

    A large sector of the West Antarctic Ice Sheet "has gone into a state of irreversible retreat," according to glaciologist Eric Rignot, lead author of the paper "Widespread rapid grounding line retreat of Pine Island, Thwaites, Smith, and Kohler Glaciers in West Antarctica from 1992 to 2011," which has been accepted for publication in Geophysical Research Letters (GRL).

  11. The degree of irreversibility in deterministic finite automata

    DEFF Research Database (Denmark)

    Axelsen, Holger Bock; Holzer, Markus; Kutrib, Martin

    2016-01-01

    for nondeterministic finite state automata (NFA) is PSPACE-complete. The recent DFA method essentially works by minimizing the DFA and inspecting it for a forbidden pattern. We here study the degree of irreversibility for a regular language, the minimal number of such forbidden patterns necessary in any DFA accepting...

  12. A criterion to maximize the irreversible efficiency in heat engines

    CERN Document Server

    Aragon-Gonzalez, G; Leon-Galicia, A; Musharrafie-Martinez, M

    2003-01-01

    The purpose of this work is to obtain a more precise calculation of the effective limits to the efficiency, of several cyclic heat engines. This calculation is based, first, on the equations describing the irreversible efficiency, and second, on a method which results from a general criterion to maximize this efficiency, applicable to several heat engines. With this method, we apply the criterion to maximize efficiencies; establish lower and upper bounds, corresponding to the efficiencies of Curzon-Ahlborn-like and Carnot-like heat engines; and, finally, find analytical or numerical expressions for the efficiencies eta sub m sub e and eta sub m sub a sub x. eta sub m sub a sub x is the maximum irreversible efficiency; eta sub m sub e is the efficiency in which the irreversible efficiency achieves its maximum, in a similar way to the Curzon-Ahlborn efficiency (maximum work or power). The method was applied to a Brayton cycle, presenting internal dissipations of the working fluid and irreversibilities due to th...

  13. Reversible and irreversible reaction fronts in two competing reactions system

    International Nuclear Information System (INIS)

    Sinder, M.; Taitelbaum, H.; Pelleg, J.

    2002-01-01

    A modeling of the non-equilibrium diffusion phenomena of the impurities in the semiconductors is based on the reaction-diffusion equations for local concentrations of the components. Through this approach a new feature, a reaction front, may be caused by reaction in diffusion profiles of the components. The asymptotic long-time properties of the reaction fronts in the system with initially separated components and two competing reactions: reversible A 1 +B↔C 1 and irreversible A 2 +B→C 2 are studied in this work. It is assumed that the backward constant of the reaction A 1 +B↔C 1 is small. The dynamics of the system is described as a cross-over between the 'irreversible' regime for small times and the 'reversible' regime for large times. It is shown that the 'irreversible' regime is characterized by single reaction zone, in which both reactions occur. The two reaction fronts, reversible A 1 +B↔C 1 and irreversible A 2 +C 1 →A 1 +C 2 appear in the 'reversible' regime. Numerical computing of the mean-field kinetics equations confirms these asymptotic results. The experimental tests of the theoretical predictions relating to the diffusion phenomena in semiconductors are discussed

  14. Report on the International Workshop on Drug Prevention and Treatment in Rural Settings Organized by United Nation Office on Drugs and Crime (UNODC) and World Health Organization (WHO).

    Science.gov (United States)

    Milano, Giulia; Saenz, Elizabeth; Clark, Nicolas; Busse, Anja; Gale, John; Campello, Giovanna; Mattfeld, Elizabeth; Maalouf, Wadih; Heikkila, Hanna; Martelli, Antonietta; Morales, Brian; Gerra, Gilberto

    2017-11-10

    Very little evidence has been reported in literature regarding the misuse of substances in rural areas. Despite the common perception of rural communities as a protective and risk-mitigating environment, the scientific literature demonstrated the existence of many risk factors in rural communities. The Drug Prevention and Health Branch (DHB) of the United Nations Office on Drugs and Crime (UNODC), and the World Health Organization (WHO), in June 2016, organized a meeting of experts in treatment and prevention of SUDs in rural settings. The content presented during the meeting and the related discussion have provided materials for the preparation of an outline document, which is the basis to create a technical tool on SUDs prevention and treatment in rural settings. The UNODC framework for interventions in rural settings is a technical tool aimed to assist policy makers and managers at the national level. This paper is a report on UNODC/WHO efforts to improve the clinical conditions of people affected by SUDs and living in rural areas. The purpose of this article is to draw attention on a severe clinical and social problem in a reality forgotten by everyone.

  15. Modern "don-quixotism" or an emerging norm of international relations? Prevention of armed conflicts in the European Union and the organization for security and cooperation in Europe

    OpenAIRE

    Zupančič, Rok

    2015-01-01

    The prevention of armed conflicts is stated as the priority policy of various international organizations, among which the EU and the OSCE. Based on the semi-structured interviews with high bureaucrats and civilian experts, who areengaged in conflict prevention policies within the two international organizations, the article compares the development and implementation of EU and OSCE strategies to prevent armed conflicts. With the support of the secondmethod, the analysis of primary and second...

  16. A Dual Chamber Stent Prevents Organ Malperfusion in a Model of Donation after Cardiac Death

    Science.gov (United States)

    Tillman, Bryan W.; Chun, Youngjae; Cho, Sung Kwon; Chen, Yanfei; Liang, Nathan; Maul, Timothy; Demetris, Anthony; Gu, Xinzhu; Wagner, William R.; Tevar, Amit D.

    2016-01-01

    Background The paradigm for Donation after Cardiac Death (DCD) subjects donor organs to significant ischemic injury. A dual-chamber Organ Perfusion Stent (OPS) would maintain organ perfusion without impacting natural cardiac death. A center lumen allows uninterrupted cardiac blood flow, while an external chamber delivers oxygenated blood to the visceral vessels. Methods A prototype OPS was constructed from commercial stents. In a porcine model, the OPS was deployed, followed by a simulated agonal period. Oxygenated blood perfused the external stent chamber. Organ perfusion was compared between controls (n=3) and OPS (n=6). Finally, a custom nitinol dual chamber OPS was fabricated using a retrievable “petal and stem” design. Results Endovascular OPS deployment achieved visceral isolation without adverse impact on cardiac parameters. Visceral oxygen delivery was 4.8 fold higher as compared to controls. During the agonal period, organs in OPS treated animals appeared well perfused, contrasting to malperfused controls. A custom nitinol and polyurethane OPS was easily recaptured with simple sheath advancement. Conclusions An OPS maintained organ perfusion during the agonal phase in a model of DCD organ donation without adversely impacting cardiac function. Ultimately, the custom retrievable design of this study may help resolve the critical shortage of donor organs for transplant. PMID:27524434

  17. Effects of Outreach on the Prevention of Aquatic Invasive Species Spread among Organism-in-Trade Hobbyists

    Science.gov (United States)

    Seekamp, Erin; Mayer, Jessica E.; Charlebois, Patrice; Hitzroth, Greg

    2016-11-01

    Releases of aquatic organisms-in-trade by aquarists, water gardeners, and outdoor pond owners have been identified as aquatic invasive species vectors within the Laurentian Great Lakes region. The trademarked U.S. Fish and Wildlife Service Habitattitude campaign was developed in 2004 to encourage self-regulation by these groups, but little is known about its effects. We surveyed organisms-in-trade hobbyists in the eight Great Lakes states (Illinois, Indiana, Michigan, Minnesota, New York, Ohio, Pennsylvania, and Wisconsin, USA) to assess their recognition of the Habitattitude campaign and their compliance with the campaign's recommended behaviors for organism purchase and disposal. Awareness of the Habitattitude campaign was low, but hobbyists that identified as both water gardeners and aquarium hobbyists were more aware of the campaign than individuals who participated in one of those hobbies. Engaged hobbyists (high aquatic invasive species awareness, concern, and knowledge) were significantly more likely than passive hobbyists (low aquatic invasive species awareness, concern, and knowledge) to make decisions about disposal of live organisms with the intention of preventing aquatic invasive species spread, were more likely to contact other hobbyists for disposal and handling advice, and were less likely to contact professionals, such as retailers. On the basis of our results, we suggest that compliance with recommended behaviors may be increased by fostering hobbyist networks; creating materials that both explain tangible, negative environmental impacts and list specific prevention behaviors; and disseminating these materials through trusted information sources and venues.

  18. Re-thinking Innovation in Organizations in the Industry 4.0 Scenario: New Challenges in a Primary Prevention Perspective

    Directory of Open Access Journals (Sweden)

    Letizia Palazzeschi

    2018-01-01

    Full Text Available In organizations, innovation is considered a relevant aspect of success and long-term survival. Organizations recognize that innovation contributes to creating competitive advantages in a more competitive, challenging and changing labor market. The present contribution addresses innovation in organizations in the scenario of Industry 4.0, including technological innovation and psychological innovation. Innovation is a core concept in this framework to face the challenge of globalized and fluid labor market in the 21st century. Reviewing the definition of innovation, the article focuses on innovative work behaviors and the relative measures. This perspective article also suggests new directions in a primary prevention perspective for future research and intervention relative to innovation and innovative work behaviors in the organizational context.

  19. Re-thinking Innovation in Organizations in the Industry 4.0 Scenario: New Challenges in a Primary Prevention Perspective.

    Science.gov (United States)

    Palazzeschi, Letizia; Bucci, Ornella; Di Fabio, Annamaria

    2018-01-01

    In organizations, innovation is considered a relevant aspect of success and long-term survival. Organizations recognize that innovation contributes to creating competitive advantages in a more competitive, challenging and changing labor market. The present contribution addresses innovation in organizations in the scenario of Industry 4.0, including technological innovation and psychological innovation. Innovation is a core concept in this framework to face the challenge of globalized and fluid labor market in the 21st century. Reviewing the definition of innovation, the article focuses on innovative work behaviors and the relative measures. This perspective article also suggests new directions in a primary prevention perspective for future research and intervention relative to innovation and innovative work behaviors in the organizational context.

  20. Choice of an Infusion Agent for the Prevention of Multiple Organ Dysfunction in Acute Massive Blood Loss (Experimental Study

    Directory of Open Access Journals (Sweden)

    A. Yu. Yakovlev

    2010-01-01

    Full Text Available Objective: to perform an experimental study of the effect of sterofundin isotonic on the biochemical parameters characterizing the degree of organ injury after acute massive blood loss (AMBL. Material and methods. Experiments were carried out on 36 male Wistar rats weighing 230—250 g. Hemorrhagic stroke was simulated via AMBL in a volume of 2.5 ml/100 g at a rate of 2 ml/min. An hour after AMBL, there was hypovolemia compensation within 60 minutes in a volume of 200% of the blood loss: by Ringer’s solution in a control group and by sterofundin isotonic in an experimental group. Then blood reinfu-sion was made in a volume of 70% of blood loss. The biochemical parameters of multiple organ dysfunction (glucose, lactate, urea, creatinine, bilirubin, total protein, albumin, enzymemia (aspartate aminotransferase, alanine aminotransferase, creatine phosphokinase, lactate dehydrogenase, amylase, endotoxemia (low- and medium-molecular-weight substances in the plasma and erythrocytes, acid-base condition, electrolytes of venous blood, and animal survival were determined on days 1 and 3 following AMBL. Results. There was a reduction in the time and degree of posthemorrhagic metabolic, biochemical, and electrolyte disorders, enzymemia, and endotoxemia in the experimental animals. Conclusion. The experimental studies suggest that Ringer’s solution is inadequately effective in preventing multiple organ dysfunction due to AMBL. The malate-containing blood substitute sterofundin isotonic that is used during early therapy for AMBL exerts a marked preventive effect on the development of visceral organ injuries when multiple organ dysfunction occurs in the early and late posthemorrhagic period. The experimental findings make it possible to recommend that sterofundin isotonic should be used in intensive care of hypovolemic shock arising from AMBL. Key words: acute massive blood loss, malate, sterofun dinisotonic, lactate, endotoxemia, multiple organ

  1. BNNT-mediated irreversible electroporatio: its potential on cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Vittoria Raffa, Cristina Riggio, Michael W. Smith, Kevin C. Jordan, Wei Cao, Alfred Cuschieri

    2012-10-01

    Tissue ablation, i.e., the destruction of undesirable tissues, has become an important minimally invasive technique alternative to resection surgery for the treatment of tumours. Several methods for tissue ablation are based on thermal techniques using cold, e.g. cryosurgery [1] or heat, e.g. radiofrequency [2] or high-intensity focused ultrasound [3] or nanoparticle-mediated irradiation [4]. Alternatively, irreversible electroporation (IRE) has been proposed as non thermal technique for minimally invasive tissue ablation based on the use of electrical pulses. When the electric field is applied to a cell, a change in transmembrane potential is induced, which can cause biochemical and physiological changes of the cell. When the threshold value of the transmembrane potential is exceeded, the cell membrane becomes permeable, thus allowing entrance of molecules that otherwise cannot cross the membrane [5]. A further increase in the electric field intensity may cause irreversible membrane permeabilization and cell death. These pulses create irreversible defects (pores) in the cell membrane lipid bilayer, causing cell death through loss of cell homeostasis [6]. This is desirable in tumour ablation in order to produce large cell death, without the use of cytostatic drugs. A study of Davalos, Mir and Rubinsky showed that IRE can ablate substantial volumes of tissue without inducing a thermal effect and therefore serve as an independent and new tissue ablation modality; this opened the way to the use of IRE in surgery [7]. Their finding was subsequently confirmed in studies on cells [8], small animal models [9] and in large animal models in the liver [10] and the heart [11]. The most important finding in these papers is that irreversible electroporation produces precisely delineated ablation zones with cell scale resolution between ablated and non-ablated areas, without zones in which the extent of damage changes gradually as during thermal ablation. Furthermore, it is

  2. Prevention of Organ Injury in Exertional Heat Stroke: Preclinical Evaluation of a New Class of NSAIDs

    Science.gov (United States)

    2017-10-01

    Nimmo MA. The anti-inflammatory effects of exercise: mechanisms and implica- tions for the prevention and treatment of disease . Nat Rev Immunol 11...Muscle Michelle King et al., FASEB J, 2015 Exposure to Oxidized Tyrosine Products Induced Glycometabolism Disorder Involving Thyroid Hormones Resistance

  3. Organic materials for the nuclear industry. Guide book for prevention and safe use

    International Nuclear Information System (INIS)

    1988-01-01

    For a safe use of organic materials (plastics, resins, rubbers) in the nuclear industry, this book reviews selection of evaluation of materials by studying their behaviour concerning ionizing radiations, fire resistance and aging [fr

  4. ROLE OF THE INTERNATIONAL ORGANIZATIONS IN PREVENTING THE COUNTERFEIT MEDICINES ENTRY INTO THE WORLD MARKETS.

    Science.gov (United States)

    Stukina, Valeryia; Dohnal, Jiri; Saloun, Jan

    2016-09-01

    30 years have passed since Conference of Experts on the Rational Use of Drugs was held in Nairobi, Kenya, from 25 to 29 November 1985, where the problem of counterfeit medicines was mentioned as the international for the first time. The problem of counterfeit medicines is not only a major threat to public health and national and private economy, but also it is of great interest for key decision-making actors at the international level. The authors analyzed what has been done since that time by international organizations. Combating the counterfeiting of medicines cannot be successfully achieved by the health sector alone - World Health Organization (WHO), - so the efforts of the other United Nations (UN) organizations relevant to counterfeiting were in need and were studied in the article: World Intellectual Property Organization (WIPO), World Trade Organization (WTO), World Customs Organization (WCO), United Nations Office on Drugs and Crime (UNODC), etc. Today WHO is unable to coordinate all their activities, so the few existing proposals for establishing a new mechanism of international cooperation have been examined. Will the MEDICRIME Convention that will enter into force on January 1, 2016 be the start of the new era in the combating with the counterfeit medicines? - the authors offered their vision on the international developments.

  5. Oral cancer prevention and control--the approach of the World Health Organization.

    Science.gov (United States)

    Petersen, Poul Erik

    2009-01-01

    Cancer is one of the most common causes of morbidity and mortality today. It is estimated that around 43% of cancer deaths are due to tobacco use, unhealthy diets, alcohol consumption, inactive lifestyles and infection. Low-income and disadvantaged groups are generally more exposed to avoidable risk factors such as environmental carcinogens, alcohol, infectious agents, and tobacco use. These groups also have less access to the health services and health education that would empower them to make decisions to protect and improve their own health. Oro-pharyngeal cancer is significant component of the global burden of cancer. Tobacco and alcohol are regarded as the major risk factors for oral cancer. The population-attributable risks of smoking and alcohol consumption have been estimated to 80% for males, 61% for females, and 74% overall. The evidence that smokeless tobacco causes oral cancer was confirmed recently by the International Agency for Research on Cancer. Studies have shown that heavy intake of alcoholic beverages is associated with nutrient deficiency, which appears to contribute independently to oral carcinogenesis. Oral cancer is preventable through risk factors intervention. Prevention of HIV infection will also reduce the incidence of HIV/AIDS-related cancers such as Kaposi sarcoma and lymphoma. The WHO Global Oral Health Programme is committed to work for country capacity building in oral cancer prevention, inter-country exchange of information and experiences from integrated approaches in prevention and health promotion, and the development of global surveillance systems for oral cancer and risk factors. The WHO Global Oral Health Programme has established a global surveillance system of oral cavity cancer in order to assess risk factors and to help the planning of effective national intervention programmes. Epidemiological data on oral cancer (ICD-10: C00-C08) incidence and mortality are stored in the Global Oral Health Data Bank. In 2007, the World

  6. Ecological optimization for an irreversible magnetic Ericsson refrigeration cycle

    Science.gov (United States)

    Wang, Hao; Wu, Guo-Xing

    2013-08-01

    An irreversible Ericsson refrigeration cycle model is established, in which multi-irreversibilities such as finite-rate heat transfer, regenerative loss, heat leakage, and the efficiency of the regenerator are taken into account. Expressions for several important performance parameters, such as the cooling rate, coefficient of performance (COP), power input, exergy output rate, entropy generation rate, and ecological function are derived. The influences of the heat leakage and the time of the regenerative processes on the ecological performance of the refrigerator are analyzed. The optimal regions of the ecological function, cooling rate, and COP are determined and evaluated. Furthermore, some important parameter relations of the refrigerator are revealed and discussed in detail. The results obtained here have general significance and will be helpful in gaining a deep understanding of the magnetic Ericsson refrigeration cycle.

  7. Irreversible adsorption of phenolic compounds by activated carbons

    Energy Technology Data Exchange (ETDEWEB)

    Grant, T.M.; King, C.J.

    1988-12-01

    Studies were undertaken to determine the reasons why phenolic sorbates can be difficult to remove and recover from activated carbons. The chemical properties of the sorbate and the adsorbent surface, and the influences of changes in the adsorption and desorption conditions were investigated. Comparison of isotherms established after different contact times or at different temperatures indicated that phenolic compounds react on carbon surfaces. The reaction rate is a strong function of temperature. Regeneration of carbons by leaching with acetone recovered at least as much phenol as did regeneration with other solvents or with displacers. The physiochemical properties of adsorbents influences irreversible uptakes. Sorbates differed markedly in their tendencies to undergo irreversible adsorption. 64 refs., 47 figs., 32 tabs.

  8. Prostaglandin E2 to diagnose between reversible and irreversible pulpitis.

    Science.gov (United States)

    Petrini, M; Ferrante, M; Ciavarelli, L; Brunetti, L; Vacca, M; Spoto, G

    2012-01-01

    The aim of this work is to verify a correlation between the grade of inflammation and the concentration of PGE2 in human dental pulp. A total of 25 human dental pulps were examined by histological analysis and radioimmunologic dosage of PGE2. The pulps used in this experiment were from healthy and symptomatic teeth; the first ones were collected from teeth destined to be extracted for orthodontic reasons. An increase was observed of PGE2 in reversible pulpitis compared with healthy pulps and with the irreversible pulpitis and the clear decrease of these when NSAIDs are taken. This study demonstrates that PGE2 level is correlated to histological analysis thus allowing to distinguish symptomatic teeth in reversible and irreversible pulpitis.

  9. Microscopic theory for the time irreversibility and the entropy production

    Science.gov (United States)

    Chun, Hyun-Myung; Noh, Jae Dong

    2018-02-01

    In stochastic thermodynamics, the entropy production of a thermodynamic system is defined by the irreversibility measured by the logarithm of the ratio of the path probabilities in the forward and reverse processes. We derive the relation between the irreversibility and the entropy production starting from the deterministic equations of motion of the whole system consisting of a physical system and a surrounding thermal environment. The derivation assumes the Markov approximation that the environmental degrees of freedom equilibrate instantaneously. Our approach provides a guideline for the choice of the proper reverse process to a given forward process, especially when there exists a velocity-dependent force. We demonstrate our idea with an example of a charged particle in the presence of a time-varying magnetic field.

  10. Thermodynamic Analysis of the Irreversibilities in Solar Absorption Refrigerators

    Directory of Open Access Journals (Sweden)

    Emma Berrich Betouche

    2016-03-01

    Full Text Available A thermodynamic analysis of the irreversibility on solar absorption refrigerators is presented. Under the hierarchical decomposition and the hypothesis of an endoreversible model, many functional and practical domains are defined. The effect of external heat source temperature on the entropy rate and on the inverse specific cooling load (ISCL multiplied by the total area of the refrigerator A/Qe are studied. This may help a constructor to well dimension the solar machine under an optimal technico-economical criterion A/Qe and with reasonable irreversibility on the refrigerator. The solar concentrator temperature effect on the total exchanged area, on the technico-economical ratio A/Qe, and on the internal entropy rate are illustrated and discussed. The originality of these results is that they allow a conceptual study of a solar absorption refrigeration cycle.

  11. Irreversible adsorption of phenolic compounds by activated carbons

    International Nuclear Information System (INIS)

    Grant, T.M.; King, C.J.

    1988-12-01

    Studies were undertaken to determine the reasons why phenolic sorbates can be difficult to remove and recover from activated carbons. The chemical properties of the sorbate and the adsorbent surface, and the influences of changes in the adsorption and desorption conditions were investigated. Comparison of isotherms established after different contact times or at different temperatures indicated that phenolic compounds react on carbon surfaces. The reaction rate is a strong function of temperature. Regeneration of carbons by leaching with acetone recovered at least as much phenol as did regeneration with other solvents or with displacers. The physiochemical properties of adsorbents influences irreversible uptakes. Sorbates differed markedly in their tendencies to undergo irreversible adsorption. 64 refs., 47 figs., 32 tabs

  12. Chinese Anti-Cancer Association as a non-governmental organization undertakes systematic cancer prevention work in China

    Science.gov (United States)

    2015-01-01

    Cancer has become the first leading cause of death in the world, particularly in low- and middle-income countries. Facing the increasing trend of cancer incidence and mortality, China issued and implemented “three-early (early prevention, early diagnosis and early treatment)” national cancer prevention plan. As the main body and dependence of social governance, non-governmental organizations (NGOs) take over the role of government in the field of cancer prevention and treatment. American Cancer Society (ACS) made a research on cancer NGOs and civil society in cancer control and found that cancer NGOs in developing countries mobilize civil society to work together and advocate governments in their countries to develop policies to address the growing cancer burden. Union for International Cancer Control (UICC), Cancer Council Australia (CCA), and Malaysian cancer NGOs are the representatives of cancer NGOs in promoting cancer control. Selecting Chinese Anti-Cancer Association (CACA) as an example in China, this article is to investigate how NGOs undertake systematic cancer prevention work in China. By conducting real case study, we found that, as a NGO, CACA plays a significant role in intensifying the leading role of government in cancer control, optimizing cancer outcomes, decreasing cancer incidence and mortality rates and improving public health. PMID:26361412

  13. Vested interests in addiction research and policy. Alcohol industry use of social aspect public relations organizations against preventative health measures.

    Science.gov (United States)

    Miller, Peter G; de Groot, Florentine; McKenzie, Stephen; Droste, Nicolas

    2011-09-01

    It has been proposed that alcohol industry 'social aspects/public relations' organizations (SAPROs) serve the agenda of lending credibility to industry claims of corporate responsibility while promoting ineffective industry-friendly interventions (such as school-based education or TV advertising campaigns) and creating doubt about interventions which have a strong evidence base (such as higher taxes on alcoholic beverages). This paper investigated whether submissions to Australia's National Preventative Health Taskforce (NPHT) from alcohol industry bodies regarding the Australian SAPRO, Drinkwise, have used this organization to demonstrate corporate responsibility while promoting industry-friendly interventions. Submissions to the Australian National Preventative Health Taskforce (NPHT) discussion paper Australia, the healthiest country by 2020 (n = 375) were examined to identify those with primary alcohol content. A thematic analysis of the resulting 33 submissions was conducted to determine which organization, institution or individual discussed Drinkwise. Australia. Nine of the 33 submissions discussed Drinkwise; all were submitted by the alcohol industry or its affiliates. Every industry submission referred to Drinkwise either as providing evidence of social responsibility or by suggesting the industry-friendly actions of Drinkwise as alternatives to those recommended by the NPHT report. Drinkwise has been used by the alcohol industry to create an impression of social responsibility while promoting interventions that maintain profits and campaigning against effective interventions such as higher taxes on alcohol. © 2011 The Authors, Addiction © 2011 Society for the Study of Addiction.

  14. Reversing the irreversible: From limit cycles to emergent time symmetry

    Science.gov (United States)

    Cortês, Marina; Smolin, Lee

    2018-01-01

    In 1979 Penrose hypothesized that the arrows of time are explained by the hypothesis that the fundamental laws are time irreversible [R. Penrose, in General Relativity: An Einstein Centenary Survey (1979)]. That is, our reversible laws, such as the standard model and general relativity are effective, and emerge from an underlying fundamental theory which is time irreversible. In [M. Cortês and L. Smolin, Phys. Rev. D 90, 084007 (2014), 10.1103/PhysRevD.90.084007; 90, 044035 (2014), 10.1103/PhysRevD.90.044035; 93, 084039 (2016), 10.1103/PhysRevD.93.084039] we put forward a research program aiming at realizing just this. The aim is to find a fundamental description of physics above the Planck scale, based on irreversible laws, from which will emerge the apparently reversible dynamics we observe on intermediate scales. Here we continue that program and note that a class of discrete dynamical systems are known to exhibit this very property: they have an underlying discrete irreversible evolution, but in the long term exhibit the properties of a time reversible system, in the form of limit cycles. We connect this to our original model proposal in [M. Cortês and L. Smolin, Phys. Rev. D 90, 084007 (2014), 10.1103/PhysRevD.90.084007], and show that the behaviors obtained there can be explained in terms of the same phenomenon: the attraction of the system to a basin of limit cycles, where the dynamics appears to be time reversible. Further than that, we show that our original models exhibit the very same feature: the emergence of quasiparticle excitations obtained in the earlier work in the space-time description is an expression of the system's convergence to limit cycles when seen in the causal set description.

  15. Irreversible pulpitis and achieving profound anesthesia: Complexities and managements

    OpenAIRE

    Modaresi, Jalil; Davoudi, Amin; Badrian, Hamid; Sabzian, Roya

    2016-01-01

    Dental pain management is one of the most critical aspects of modern dentistry. Irreversible pulpitis and further root canal therapy might cause an untolerated pain to the patients. The improvements in anesthetic agents and techniques were one of the advantages of studying nerve biology and stimulation. This article tried to overview of the nerve activities in inflammatory environments or induced pain. Furthermore, the proper advises, and supplementary techniques were reviewed for better pain...

  16. Irreversibility and chaos: role of lubrication interactions in sheared suspensions.

    Science.gov (United States)

    Metzger, Bloen; Pham, Phong; Butler, Jason E

    2013-05-01

    We investigate non-Brownian particles suspended in a periodic shear-flow using simulations. Following Metzger and Butler [Phys. Rev. E 82, 051406 (2010)], we show that the chaotic dynamics arising from lubrication interactions are too weak to generate an observable particle dispersion. The irreversibility observed in periodic flow is dominated by contact interactions. Nonetheless, we show that lubrication interactions must be included in the calculation to obtain results that agree with experiments.

  17. Sacrificial salts: Compensating the initial charge irreversibility in lithium batteries

    Energy Technology Data Exchange (ETDEWEB)

    Shanmukaraj, Devaraj; Grugeon, Sylvie; Laruelle, Stephane; Douglade, Gregory; Tarascon, Jean-Marie; Armand, Michel [Laboratoire de Reactivite et de Chimie des Solides, UMR CNRS 6007, Universite de Picardie Jules Verne, Amiens (France)

    2010-10-15

    Lithium salts enlisting azide, oxocarbons, dicarboxylates and hydrazides have been identified as a practical mean to compensate the irreversible capacity loss of LIBs negative electrodes. During the first charge, the anion loses electrons and converts to gaseous N{sub 2}, CO or CO{sub 2}, within an acceptable potential range (3 to 4.5 V). We report an electrochemical study on these easily accessible 'sacrificial salts'. (author)

  18. Oral cancer prevention and control--the approach of the World Health Organization

    DEFF Research Database (Denmark)

    Petersen, Poul Erik

    2009-01-01

    national intervention programmes. Epidemiological data on oral cancer (ICD-10: C00-C08) incidence and mortality are stored in the Global Oral Health Data Bank. In 2007, the World Health Assembly (WHA) passed a resolution on oral health for the first time in 25 years, which also considers oral cancer...... risk factors such as environmental carcinogens, alcohol, infectious agents, and tobacco use. These groups also have less access to the health services and health education that would empower them to make decisions to protect and improve their own health. Oro-pharyngeal cancer is significant component....... Prevention of HIV infection will also reduce the incidence of HIV/AIDS-related cancers such as Kaposi sarcoma and lymphoma. The WHO Global Oral Health Programme is committed to work for country capacity building in oral cancer prevention, inter-country exchange of information and experiences from integrated...

  19. [The organization of the comprehensive prevention of urolithiasis among ferrous metallurgy workers].

    Science.gov (United States)

    Egorova, A M

    2009-01-01

    The purpose of study is to evaluate the effectiveness of the set of preventive measures as applied to 321 workers of basic ferrous metallurgy specialties (steel makers, mill men, hot metal shearers). During the clinical examination all the workers were divided on three groups: the workers without any pathology (11.83%, the first group), the workers with metabolic disorders only without urolitiasis (64.81%, the second group) and the workers with urolitiasis diagnosis approved by ultrasonography (23.36%, the third group). The effectiveness of rehabilitation measures was evaluated during half a year (diet therapy, drinking regimen, medicinal plants treatment). After the course of preventive measures was applied the overall health condition of most workers ameliorated and the number of workers with urolitiasis development risk factors reliably decreased up to 6-12%.

  20. VIEWS REGARDING THE ORGANIZATION OF THE ACTIVITIES RELATEDTO THE PREVENTION AND COMBAT AGAINST MONEY LAUNDERING

    OpenAIRE

    DUMITRESCU Serju; AVRAM Marioara

    2012-01-01

    The present paper tries to render different aspects of money laundering in Romania according to the present legislation. We have tried to identify several aspects related to this issue such as: the sequences of the money laundering process, the entities having reporting obligations, the duties of the persons in charge with the prevention & combat against money laundering, report deadlines, different types of reporting which have to be done to the Money Laundering Department , the contraventio...

  1. Irreversibility and complex network behavior of stream flow fluctuations

    Science.gov (United States)

    Serinaldi, Francesco; Kilsby, Chris G.

    2016-05-01

    Exploiting the duality between time series and networks, directed horizontal visibility graphs (DHVGs) are used to perform an unprecedented analysis of the dynamics of stream flow fluctuations with focus on time irreversibility and long range dependence. The analysis relies on a large quality-controlled data set consisting of 699 daily time series recorded in the continental United States (CONUS) that are not affected by human activity and primarily reflects meteorological conditions. DHVGs allow a clear visualization and quantification of time irreversibility of flow dynamics, which can be interpreted as a signature of nonlinearity, and long range dependence resulting from the interaction of atmospheric, surface and underground processes acting at multiple spatio-temporal scales. Irreversibility is explored by mapping the time series into ingoing, outgoing, and undirected graphs and comparing the corresponding degree distributions. Using surrogate data preserving up to the second order linear temporal dependence properties of the observed series, DHVGs highlight the additional complexity introduced by nonlinearity into flow fluctuation dynamics. We show that the degree distributions do not decay exponentially as expected, but tend to follow a subexponential behavior, even though sampling uncertainty does not allow a clear distinction between apparent or true power law decay. These results confirm that the complexity of stream flow dynamics goes beyond a linear representation involving for instance the combination of linear processes with short and long range dependence, and requires modeling strategies accounting for temporal asymmetry and nonlinearity.

  2. Irreversible Local Markov Chains with Rapid Convergence towards Equilibrium

    Science.gov (United States)

    Kapfer, Sebastian C.; Krauth, Werner

    2017-12-01

    We study the continuous one-dimensional hard-sphere model and present irreversible local Markov chains that mix on faster time scales than the reversible heat bath or Metropolis algorithms. The mixing time scales appear to fall into two distinct universality classes, both faster than for reversible local Markov chains. The event-chain algorithm, the infinitesimal limit of one of these Markov chains, belongs to the class presenting the fastest decay. For the lattice-gas limit of the hard-sphere model, reversible local Markov chains correspond to the symmetric simple exclusion process (SEP) with periodic boundary conditions. The two universality classes for irreversible Markov chains are realized by the totally asymmetric SEP (TASEP), and by a faster variant (lifted TASEP) that we propose here. We discuss how our irreversible hard-sphere Markov chains generalize to arbitrary repulsive pair interactions and carry over to higher dimensions through the concept of lifted Markov chains and the recently introduced factorized Metropolis acceptance rule.

  3. Irreversible performance of a quantum harmonic heat engine

    Science.gov (United States)

    Rezek, Yair; Kosloff, Ronnie

    2006-05-01

    The unavoidable irreversible loss of power in a heat engine is found to be of quantum origin. Following thermodynamic tradition, a model quantum heat engine operating in an Otto cycle is analysed, where the working medium is composed of an ensemble of harmonic oscillators and changes in volume correspond to changes in the curvature of the potential well. Equations of motion for quantum observables are derived for the complete cycle of operation. These observables are sufficient to determine the state of the system and with it all thermodynamical variables. Once the external controls are set, the engine settles to a limit cycle. Conditions for optimal work, power and entropy production are derived. At high temperatures and quasistatic operating conditions, the efficiency at maximum power coincides with the endoreversible result \\eta_q=1-\\sqrt{{T_c}/{T_h}} . The optimal compression ratio varies from {\\cal C} =\\sqrt{T_h/T_c} in the quasistatic limit where the irreversibility is dominated by heat conductance to {\\cal C} =(T_h/T_c)^{1/4} in the sudden limit when the irreversibility is dominated by friction. When the engine deviates from adiabatic conditions, the performance is subject to friction. The origin of this friction can be traced to the noncommutability of the kinetic and potential energy of the working medium.

  4. Anesthetic Efficacy in Irreversible Pulpitis: A Randomized Clinical Trial.

    Science.gov (United States)

    Allegretti, Carlos E; Sampaio, Roberta M; Horliana, Anna C R T; Armonia, Paschoal L; Rocha, Rodney G; Tortamano, Isabel Peixoto

    2016-01-01

    Inferior alveolar nerve block has a high failure rate in the treatment of mandibular posterior teeth with irreversible pulpitis. The aim of this study was to compare the anesthetic efficacy of 4% articaine, 2% lidocaine and 2% mepivacaine, all in combination with 1:100,000 epinephrine, in patients with irreversible pulpitis of permanent mandibular molars during a pulpectomy procedure. Sixty-six volunteers from the Emergency Center of the School of Dentistry, University of São Paulo, randomly received 3.6 mL of local anesthetic as a conventional inferior alveolar nerve block (IANB). The subjective signal of lip numbness, pulpal anesthesia and absence of pain during the pulpectomy procedure were evaluated respectively, by questioning the patient, stimulation using an electric pulp tester and a verbal analogue scale. All patients reported the subjective signal of lip numbness. Regarding pulpal anesthesia success as measured with the pulp tester, the success rate was respectively 68.2% for mepivacaine, 63.6% for articaine and 63.6% for lidocaine. Regarding patients who reported no pain or mild pain during the pulpectomy, the success rate was, respectively 72.7% for mepivacaine, 63.6% for articaine and 54.5% for lidocaine. These differences were not statistically significant. Neither of the solutions resulted in 100% anesthetic success in patients with irreversible pulpitis of mandibular molars.

  5. Irreversibility analysis in the process of solar distillation

    International Nuclear Information System (INIS)

    Chávez, S; Terres, H; Lizardi, A; López, R; Lara, A

    2017-01-01

    In this work an irreversibility analysis for the thermal process of solar distillation of three different substances is presented, for which it employs a solar still of a slope where three experimental tests with 5.5 L of brine, river water and MgCl 2 were performed. Temperature data principally in the glass cover, absorber plate, fluid, environment and the incident solar radiation on the device were obtained. With measurements of temperature, solar radiation and exergetic balance, irreversibilities are found on the device. The results show that the highest values of irreversibilities are concentrated in the absorber plate with an average of 321 W, 342 W and 276 W, followed by the cover glass with an average of 75.8 W, 80.4 W and 86.7 W and finally the fluid with 15.3 W, 15.9 W and 16 W, for 5.5 L of brine, river water and MgCl 2 . (paper)

  6. Irreversible dynamics, Onsager-Casimir symmetry, and an application to turbulence.

    Science.gov (United States)

    Ottinger, Hans Christian

    2014-10-01

    Irreversible contributions to the dynamics of nonequilibrium systems can be formulated in terms of dissipative, or irreversible, brackets. We discuss the structure of such irreversible brackets in view of a degeneracy implied by energy conservation, where we consider different types of symmetries of the bracket corresponding to the Onsager and Casimir symmetries of linear irreversible thermodynamics. Slip and turbulence provide important examples of antisymmetric irreversible brackets and offer guidance for the more general modeling of irreversible dynamics without entropy production. Conversely, turbulence modeling could benefit from elucidating thermodynamic structure. The examples suggest constructing antisymmetric irreversible brackets in terms of completely antisymmetric functions of three indices. Irreversible brackets without well-defined symmetry properties can arise for rare events, causing big configurational changes.

  7. Next-generation calcineurin inhibitors in development for the prevention of organ rejection

    Directory of Open Access Journals (Sweden)

    Gheith O

    2014-03-01

    Full Text Available Osama Gheith, Torki Al-Otaibi, Hany MansourDepartment of Nephrology, Hamed Al-Essa Organ Transplant Center, Ibn Sina Hospital, Shuwaikh, KuwaitAbstract: Calcineurin inhibitors (CNIs remain the cornerstone of immunosuppression after renal transplantation despite their adverse effects. Some CNIs have well known negative impacts on the cardiovascular system, including hypertension, hyperlipidemia, new onset diabetes after transplantation (NODAT, neurotoxicity, hypertrichosis, and nephrotoxicity. Many clinical trials dealing with CNI avoidance or elimination were associated with higher risk of rejection of the transplanted organ. New generation CNIs are concerned with modifying CNI molecules so that they become more potent and are suitable for patients with suboptimal adherence with less adverse effects. In this review, we address these issues.Keywords: calcineurin inhibitors, organ transplant, rejection

  8. Organ-Specific Exposure and Response to Sulforaphane, a Key Chemopreventive Ingredient in Broccoli: Implications for Cancer Prevention

    Science.gov (United States)

    Veeranki, Omkara L.; Bhattacharya, Arup; Marshall, James R.; Zhang, Yuesheng

    2012-01-01

    Naturally occurring sulforaphane (SF) has been extensively studied for cancer prevention. However, little is known as to which organs may be most affected by this agent, which impedes its further development. In the present study, SF was administered to rats orally either in a single dose or once daily for 7 days. Tissue distribution of SF was measured by a high-performance liquid chromatography-based method. Glutathione S-transferase (GST) and NAD(P)H:quinone oxidoreductase 1 (NQO1), two well-known cytoprotective Phase 2 enzymes, were measured using biochemical assays to assess tissue response to SF. SF was delivered to different organs in vastly different concentrations. Tissue uptake of SF was the greatest in the stomach, declining rapidly in the descending gastrointestinal tract. SF was rapidly eliminated through urinary excretion, and urinary concentrations of SF equivalents were 2–4 orders of magnitude higher than those of plasma. Indeed, tissue uptake level of SF in the bladder was second only to that in the stomach. Tissue levels of SF in colon, prostate and several other organs were very low, compared to those in the bladder and stomach. Moreover, induction levels of GST and NQO1 varied by 3 to 6 fold among the organs of SF-treated rats, though not strictly correlated with tissue exposure to SF. Thus, there is profound organ specificity in tissue exposure and response to dietary SF, suggesting that the potential chemopreventive benefit of dietary SF may differ significantly among organs. These findings may provide a basis for prioritizing organs for further chemopreventive study of SF. PMID:22464629

  9. The anti-inflammatory effects of matrix metalloproteinase-3 on irreversible pulpitis of mature erupted teeth.

    Science.gov (United States)

    Eba, Hisanori; Murasawa, Yusuke; Iohara, Koichiro; Isogai, Zenzo; Nakamura, Hiroshi; Nakamura, Hiroyuki; Nakashima, Misako

    2012-01-01

    Matrix metalloproteinases (MMPs) are involved in extracellular matrix degradation and the modulation of cell behavior. These proteinases have also been implicated in tissue repair and regeneration. Our previous studies have demonstrated that MMP-3 elicits stimulatory effects on the proliferation and the migration of endothelial cells as well as anti-apoptotic effects on these cells in vitro. In addition, we found that MMP-3 enhanced the regeneration of lost pulp tissue in a rat incisor pulp injury model. However, continuously erupting rodent incisors exhibit significantly different pulp organization compared with mature erupted teeth. Therefore, we have further extended these studies using a canine irreversible pulpitis model to investigate the effects of MMP-3. In this study, the crowns of the canine mature premolars were removed and the pulp tissues were amputated. The amputated pulp tissues remained exposed for 24 or 72 hours to induce mild or severe irreversible pulpitis, respectively, followed by sealing of the cavities. In both models, the whole pulp tissues became necrotic by day 14. In this mild pulpitis model, the regeneration of pulp tissue with vasculature and nerves was observed until 14 days after sealing with MMP-3, followed by extracellular matrix formation in the regenerated pulp tissues until day 28. The treatment with MMP-3 resulted in a decrease in the number of macrophage and antigen-presenting cells and a significant inhibition of IL-6 expression on day 3. The inhibition of MMP-3 activity abolished these anti-inflammatory effects. Immunofluorescence staining demonstrated that MMP-3 was involved in the modification of serum-derived hyaluronan-associated proteins and hyaluronan (SHAP-HA) complexes possibly through the degradation of versican. These results demonstrate that MMP-3 can act as an anti-inflammatory agent and suggest that MMP-3 might represent a useful therapy for the treatment of mild irreversible pulpitis.

  10. The anti-inflammatory effects of matrix metalloproteinase-3 on irreversible pulpitis of mature erupted teeth.

    Directory of Open Access Journals (Sweden)

    Hisanori Eba

    Full Text Available Matrix metalloproteinases (MMPs are involved in extracellular matrix degradation and the modulation of cell behavior. These proteinases have also been implicated in tissue repair and regeneration. Our previous studies have demonstrated that MMP-3 elicits stimulatory effects on the proliferation and the migration of endothelial cells as well as anti-apoptotic effects on these cells in vitro. In addition, we found that MMP-3 enhanced the regeneration of lost pulp tissue in a rat incisor pulp injury model. However, continuously erupting rodent incisors exhibit significantly different pulp organization compared with mature erupted teeth. Therefore, we have further extended these studies using a canine irreversible pulpitis model to investigate the effects of MMP-3. In this study, the crowns of the canine mature premolars were removed and the pulp tissues were amputated. The amputated pulp tissues remained exposed for 24 or 72 hours to induce mild or severe irreversible pulpitis, respectively, followed by sealing of the cavities. In both models, the whole pulp tissues became necrotic by day 14. In this mild pulpitis model, the regeneration of pulp tissue with vasculature and nerves was observed until 14 days after sealing with MMP-3, followed by extracellular matrix formation in the regenerated pulp tissues until day 28. The treatment with MMP-3 resulted in a decrease in the number of macrophage and antigen-presenting cells and a significant inhibition of IL-6 expression on day 3. The inhibition of MMP-3 activity abolished these anti-inflammatory effects. Immunofluorescence staining demonstrated that MMP-3 was involved in the modification of serum-derived hyaluronan-associated proteins and hyaluronan (SHAP-HA complexes possibly through the degradation of versican. These results demonstrate that MMP-3 can act as an anti-inflammatory agent and suggest that MMP-3 might represent a useful therapy for the treatment of mild irreversible pulpitis.

  11. Exploration of Islamic medicine plant extracts as powerful antifungals for the prevention of mycotoxigenic Aspergilli growth in organic silage

    DEFF Research Database (Denmark)

    Tayel, Ahmed A.; Salem, Mohammed F.; El-Tras, Wael F.

    2011-01-01

    Feed contamination with mycotoxins is a major risk factor for animals and humans as several toxins can exist as residues in meat and milk products, giving rise to carry-over to consumers via ingestion of foods of animal origin. The starting point for prevention, in this chain, is to eliminate...... the growth of mycotoxigenic fungi in the animal forage. Ten plant extracts, recommended in Islamic medicine, were evaluated as antifungal agents against mycotoxigenic Aspergilli, i.e. Aspergillus flavus and A. ochraceus, growth in organic maize silage....

  12. Summary of the British Transplantation Society Guidelines for the Prevention and Management of CMV Disease After Solid Organ Transplantation.

    Science.gov (United States)

    Andrews, Peter A; Emery, Vincent C; Newstead, Chas

    2011-12-15

    The third edition of the British Transplantation Society Guidelines for the Prevention and Management of CMV Disease after Solid Organ Transplantation was published in March 2011. This article summarizes the important changes and advances in management in this rapidly evolving field. The pros and cons of universal, or targeted anti-cytomegalovirus (CMV) prophylaxis, and pre-emptive anti-CMV therapy are discussed, especially with respect to advances in CMV polymerase chain reaction monitoring. The evidence for oral anti-CMV prophylaxis using valganciclovir is presented, together with a summary of the treatment of CMV disease and emerging fields such as CMV vaccination, CMV genotyping, and drug resistance.

  13. Identification of measures for prevention of black spots in organically produced stored carrots

    NARCIS (Netherlands)

    Köhl, J.; Kastelein, P.; Elderson, J.; Blok, W.J.

    2005-01-01

    In the Netherlands winter carrot for the fresh market is a cash crop for many organic growers of field vegetables. In the last few years blackish spots have been observed during storage of carrot roots. An inventory was carried out in 2001/2002 and 2002/2003 including in total 42 carrot lots from 22

  14. World Allergy Organization-McMaster University Guidelines for Allergic Disease Prevention (GLAD-P): Vitamin D.

    Science.gov (United States)

    Yepes-Nuñez, Juan José; Fiocchi, Alessandro; Pawankar, Ruby; Cuello-Garcia, Carlos A; Zhang, Yuan; Morgano, Gian Paolo; Ahn, Kangmo; Al-Hammadi, Suleiman; Agarwal, Arnav; Gandhi, Shreyas; Beyer, Kirsten; Burks, Wesley; Canonica, Giorgio W; Ebisawa, Motohiro; Kamenwa, Rose; Lee, Bee Wah; Li, Haiqi; Prescott, Susan; Riva, John J; Rosenwasser, Lanny; Sampson, Hugh; Spigler, Michael; Terracciano, Luigi; Vereda, Andrea; Waserman, Susan; Schünemann, Holger J; Brożek, Jan L

    2016-01-01

    The prevalence of allergic diseases is approximately 10 % in infants whose parents and siblings do not have allergic diseases and 20-30 % in those with an allergic first-degree relative. Vitamin D is involved in the regulation of the immune system and it may play a role in the development, severity and course of asthma and other allergic diseases. The World Allergy Organization (WAO) convened a guideline panel to develop evidence-based recommendations addressing the use of vitamin D in primary prevention of allergic diseases. Our WAO guideline panel identified the most relevant clinical questions and performed a systematic review of randomized controlled trials and non-randomized studies (NRS), specifically cohort and case-control studies, of vitamin D supplementation for the prevention of allergic diseases. We also reviewed the evidence about values and preferences, and resource requirements (up to January 2015, with an update on January 30, 2016). We followed the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach to develop recommendations. Having reviewed the currently available evidence, the WAO guideline panel found no support for the hypothesis that vitamin D supplementation reduces the risk of developing allergic diseases in children. The WAO guideline panel suggest not using vitamin D in pregnant women, breastfeeding mothers, or healthy term infants as a means of preventing the development of allergic diseases. This recommendation does not apply to those mothers and infants who have other indications for prophylactic or therapeutic use of vitamin D. The panel's recommendations are conditional and supported by very low certainty evidence. WAO recommendations about vitamin D supplementation for the prevention of allergic diseases support parents, clinicians and other health care professionals in their decisions whether or not to use vitamin D in preventing allergic diseases in healthy, term infants.

  15. The organization and financing of cervical cancer prevention carried out by midwives in primary health care.

    Science.gov (United States)

    Sobczyk, Karolina; Woźniak-Holecka, Joanna; Holecki, Tomasz; Szałabska, Dorota

    2016-01-01

    The main objective of the project was the evaluation of the organizational and financial aspects of midwives in primary health care (PHC), functioning under The Population Program for the Early Detection of Cervical Cancer two years after the implementation of new law regulations, which enable this occupational group to collect cytological material for screening. Under this project, the data of the Program's Coordinating Centre, affecting midwives' postgraduate education in the field of pap smear tests, was taken into analysis. Furthermore, The National Health Fund (NFZ) reports on contracts entered in the field of the discussed topics, taking into consideration the value of health services performed within the Program in respect of ambulatory care and primary care units. NFZ concluded contracts for the provision of PHC service with 6124 service providers in 2016, including the contracts in the field of providing health services under the cervical cancer prevention program by PHC midwifes, which were entered into by 358 institutions (5.85%). The value of the basic services under the Program, carried out under NFZ contracts in 2014, amounted to approx. PLN 12.3 million, while the value of services performed by PHC midwives represented only 0.38% of this sum. The introduction of legislative changes, allowing PHC midwives to collect cytological material for screening, did not cause, in the period of the observation on a national scale, the expected growth of availability of basic stage services within the cervical cancer prevention program.

  16. IMPROVING FINANCIAL ANALYSIS OF ORGANIZATIONS IN ORDER TO PREVENT THEIR INSOLVENCY

    Directory of Open Access Journals (Sweden)

    V. N. Alferov

    2012-01-01

    Full Text Available The current regulatory analysis of the financial condition of insolvent organizations have some disadvantages also does not account the features of the analysis based on the consolidated financial statements under IFRS and GAAP. In this work on the basis of the comparative analysis of financial condition of a number of large Russian companies, calculated on their accounting statements prepared under Russian accounting standards, IFRS and GAAP, proposals are developed to improve the analysis of financial condition of insolvent institutions.

  17. IMPROVING FINANCIAL ANALYSIS OF ORGANIZATIONS IN ORDER TO PREVENT THEIR INSOLVENCY

    Directory of Open Access Journals (Sweden)

    V. N. Alferov

    2013-01-01

    Full Text Available The current regulatory analysis of the financial condition of insolvent organizations have some disadvantages also does not account the features of the analysis based on the consolidated financial statements under IFRS and GAAP. In this work on the basis of the comparative analysis of financial condition of a number of large Russian companies, calculated on their accounting statements prepared under Russian accounting standards, IFRS and GAAP, proposals are developed to improve the analysis of financial condition of insolvent institutions.

  18. The efficacy of active drainage for preventing postoperative organ/space surgical site infections in patients with Crohn's disease.

    Science.gov (United States)

    Ikeshima, Ryo; Mizushima, Tsunekazu; Takahashi, Hidekazu; Haraguchi, Naotsugu; Nishimura, Junichi; Hata, Taishi; Matsuda, Chu; Ikenaga, Masakazu; Nakajima, Kiyokazu; Yamamoto, Hirofumi; Murata, Kohei; Doki, Yuichiro; Mori, Masaki

    2018-01-01

    Patients with Crohn's disease (CD) show a higher incidence of surgical site infections (SSIs) after bowel resection in comparison to other patient populations because CD patients commonly suffer from anemia, malnutrition, and immunosuppression. In comparison to conventional passive drainage, active drainage using a closed-suction drain reportedly reduces postoperative wound-related complications in several diseases. In the present study, we aimed to investigate the incidence of SSI and to identify the risk factors for SSI in patients with CD. We retrospectively analyzed the patient characteristics and perioperative data of 106 CD patients who underwent bowel resection at our institution between January 2000 and June 2016. We statistically analyzed the incidence of different types of SSI (overall, incisional, and organ/space) in relation to patient-related and surgery-related risk factors. Overall postoperative SSIs were diagnosed in 19 patients (17.9%), including incisional SSI (n = 16; 15.1%), organ/space SSI (n = 7; 6.6%), and both (n = 4; 3.8%). A long operative time (p = 0.036) and colonic involvement (p = 0.011) were significantly associated with the overall risk of developing an SSI. Active drainage significantly reduced the incidence of organ/space SSI (p = 0.037). Intraabdominal active drainage was more useful than passive drainage for preventing organ/space SSI development.

  19. Resource mobilization for health advocacy: Afro-Brazilian religious organizations and HIV prevention and control.

    Science.gov (United States)

    Garcia, Jonathan; Parker, Richard G

    2011-06-01

    Brazil's national response to AIDS has been tied to the ability to mobilize resources from the World Bank, the World Health Organization, and a variety of donor agencies. The combination of favorable political economic opportunities and the bottom-up demands from civil society make Brazil a particularly interesting case. Despite the stabilization of the AIDS epidemic within the general Brazilian population, it continues to grow in pockets of poverty, especially among women and blacks. We use resource mobilization theories to examine the role of Afro-Brazilian religious organizations in reaching these marginalized populations. From December 2006 through November 2008, we conducted ethnographic research, including participant observation and oral histories with religious leaders (N = 18), officials from the National AIDS Program (N = 12), public health workers from Rio de Janeiro (N = 5), and non-governmental organization (NGO) activists who have worked with Afro-Brazilian religions (N = 5). The mobilization of resources from international donors, political opportunities (i.e., decentralization of the National AIDS Program), and cultural framings enabled local Afro-Brazilian religious groups to forge a national network. On the micro-level, in Rio de Janeiro, we observed how macro-level structures led to the proliferation of capacity-building and peer educator projects among these religious groups. We found that beyond funding assistance, the interrelation of religious ideologies, leadership, and networks linked to HIV can affect mobilization. Copyright © 2010 Elsevier Ltd. All rights reserved.

  20. The New World Health Organization Recommendations on Perioperative Administration of Oxygen to Prevent Surgical Site Infections: A Dangerous Reductionist Approach?

    Science.gov (United States)

    Wenk, Manuel; Van Aken, Hugo; Zarbock, Alexander

    2017-08-01

    In October 2016, the World Health Organization (WHO) published recommendations for preventing surgical site infections (SSIs). Among those measures is a recommendation to administer oxygen at an inspired fraction of 80% intra- and postoperatively for up to 6 hours. SSIs have been identified as a global health problem, and the WHO should be commended for their efforts. However, this recommendation focuses only on the patient's "wound," ignores other organ systems potentially affected by hyperoxia, and may ultimately worsen patient outcomes.The WHO advances a "strong recommendation" for the use of a high inspired oxygen fraction even though the quality of evidence is only moderate. However, achieving this goal by disregarding other potentially lethal complications seems inappropriate, particularly in light of the weak evidence underpinning the use of high fractions of oxygen to prevent SSI. Use of such a strategy thus should be intensely discussed by anesthesiologists and perioperative physicians.Normovolemia, normotension, normoglycemia, normothermia, and normoventilation can clearly be safely applied to most patients in most clinical scenarios. But the liberal application of hyperoxemia intraoperatively and up to 6 hours postoperatively, as suggested by the WHO, is questionable from the viewpoint of anesthesia and perioperative medicine, and its effects will be discussed in this article.

  1. Positive Relational Management for healthy organizations: psychometric properties of a new scale for prevention for workers

    Directory of Open Access Journals (Sweden)

    Annamaria Di Fabio

    2016-10-01

    Full Text Available This contribution aims at evaluating the psychometric properties of the Positive Relational Management Scale (PRMS in a sample of two hundred and fifty-one Italian workers. The dimensionality, reliability, and concurrent validity of the scale were investigated. Confirmatory factor analysis supported a correlated three-dimensional version of the scale, comprising Respect, Caring, and Connectedness. Latent correlations among the dimensions were moderate-to-strong (.44 - .57, but suggestive of the multidimensionality of the scores. In addition, good internal consistency was confirmed. The concurrent validity is good as the Pearson’s correlations between PRMS and measure for social support, life satisfaction, life meaningfulness, and flourishing range from .39 to .52. The results indicate that the PRMS is a valid instrument for measuring positive relational management at work in the Italian context within a positive preventive perspective.

  2. Positive Relational Management for Healthy Organizations: Psychometric Properties of a New Scale for Prevention for Workers.

    Science.gov (United States)

    Di Fabio, Annamaria

    2016-01-01

    This contribution aims at evaluating the psychometric properties of the Positive Relational Management Scale (PRMS) in a sample of 251 Italian workers. The dimensionality, reliability, and concurrent validity of the scale were investigated. Confirmatory factor analysis supported a correlated three-dimensional version of the scale, comprising Respect, Caring, and Connectedness. Latent correlations among the dimensions were moderate-to-strong (0.44-0.57), but suggestive of the multidimensionality of the scores. In addition, good internal consistency was confirmed. The concurrent validity is good as the Pearson's correlations between PRMS and measure for social support, life satisfaction, life meaningfulness, and flourishing range from 0.39 to 0.52. The results indicate that the PRMS is a valid instrument for measuring positive relational management at work in the Italian context within a positive preventive perspective.

  3. The World Health Organization (WHO) dataset for guiding suicide prevention policies: A 3-decade French national survey.

    Science.gov (United States)

    Fond, Guillaume; Zendjidjian, Xavier; Boucekine, Mohamed; Brunel, Lore; Llorca, Pierre-Michel; Boyer, Laurent

    2015-12-01

    Public health policies aim to prevent suicide in the general population. Assessing their effectiveness is required to further guide public health policies. The present article focuses on the French paradox. The French health care system was classified as the best in the world according the World Health Organization (WHO). However, suicide rates in France remain high compared to other European countries. The aim of the present article was to analyze (i) the evolution of suicide Age-Standardized Death (ASDRs) in France during the last three decades and the associations with socio-economic parameters and (ii) to understand which populations may specifically benefit from further targeted suicide prevention policies. The database of the World Health Organization (WHO), freely available, was explored in April 2015. ASDRs were calculated each year by ratio between the number of deaths by suicide and the total population (per 100,000 inhabitants). Number of deaths by gender and age were also analyzed. Overall, ASDR suicide has decreased since 1987 in France (-32.8% between 1987 and 2010). However, France kept the same rank (10/26) when compared to other European countries between 1987 and 2010. The relative burden of suicide in all-causes mortality increased during the same period (+28.2%) while the total number of deaths by suicide increased only slightly (+3.9%). More specifically, the number of deaths by suicide increased substantially in [35-54] years old (+40%) and 75+ years old (+27%) males, and in [35-54] (+41%) years old females. Between 2000 and 2010, suicide rates significantly decreased when yearly mean income increased, and when general and psychiatric care beds decreased. Although ASDR suicide has decreased in France since 1987, this decline is quite modest when considering its universal access to care, the prevention of depression and suicide public policies. Suicide prevention public policies should focus on evaluation and improvement of prevention and care

  4. Modern forms of organization of medical and preventive support of premature infants in Russian Federation

    Directory of Open Access Journals (Sweden)

    E. S. Keshishyan

    2017-01-01

    Full Text Available The high frequency of injuries to immature internal organs and body systems of premature infants in the postnatal period contributes to the formation of chronic pathology and the violation of neurocognitive development, making a significant contribution to the global problem of the growth of non-infectious diseases and programming the future health of the population. The main goal of health care system modern reform in the Russian Federation and around the world is to find the most effective and economical way of providing medical care, to increase significance of outpatient service and to give attention to prophylaxis. The most functional and cost-effective structure of medical care for premature infants is specialized center with a three-level support system. It consists of ambulatory counselling, the oneday hospital for medical abilitation, and full-day hospital for treatment and complex diagnostic procedures, on the system of telemedicine. The organization of the center requires a clear definition of the structure, standards of staffing and methodology of approach to the organization of support for premature infants after discharge from the neonatal hospital, taking into account the specifics of the planned and regulatory and financial indicators of medical care and the complexity of setting a clinical diagnosis in the modern conditions in the Russian Federation. In accordance to stable tendency of increasing in the survial rate of premature infants, the uniform register would be created – in base of major medical scientific and practical centre as a logistic regression model, that will make possibilities for randomize clinical studies of evidence-based nature.

  5. Irreversible Aspects of Continuum Mechanics and Transfer of Physical Characteristics in Moving Fluids : Symposia

    CERN Document Server

    Sedov, L

    1968-01-01

    At its meeting on April 23, 1965 in Paris the Bureau of IUTAM decided to have a Symposium on the Irreversible Aspects of Continaum Mechanics held in June 1966 in Vienna. In addition, a Symposium on the Transfer of Physical Characteristics in Moving Fluids which, orig­ inally, had been scheduled to take place in Stockholm was rescheduled to be held in Vienna immediately following the Symposium on the Irre­ versible Aspects of Continuum Mechanics. It was felt that the subjects of the two symposia were so closely related that participants should be given an opportunity to attend both. Both decisions were unanimously approved by the members of the General Assembly of IUTAM. Prof. H. PARKUS, Vienna, was appointed Chairman of the Symposium on the Irreversible Aspects, and Prof. L. I. SEDOV, Moscow, was appointed Chairman of the Symposium on the Transfer of Physical Characteristics, with Prof. P ARKUS being re­ sponsible for the local organization of both symposia. In accordance with the policy set forth by IUTAM...

  6. Pollution prevention opportunity assessment for building 878, manufacturing science and technology, organization 14100.

    Energy Technology Data Exchange (ETDEWEB)

    Klossner, Kristin Ann

    2004-05-01

    This report describes the methodology, analysis and conclusions of a preliminary assessment carried out for activities and operations at Sandia National Laboratories Building 878, Manufacturing Science and Technology, Organization 14100. The goal of this assessment is to evaluate processes being carried out within the building to determine ways to reduce waste generation and resource use. The ultimate purpose of this assessment is to analyze and prioritize processes within Building 878 for more in-depth assessments and to identify projects that can be implemented immediately.

  7. Dimensional Stability of Color-Changing Irreversible Hydrocolloids after Disinfection

    Directory of Open Access Journals (Sweden)

    Khaledi AAR

    2015-03-01

    Full Text Available Statement of Problem: Disinfection of dental impressions is a weak point in the dental hygiene chain. In addition, dental office personnel and dental technicians are endangered by cross-contamination. Objectives: This study aimed to investigate the dimensional stability of two color-changing irreversible hydrocolloid materials (IH after disinfection with glutaraldehyde. Materials and Methods: In this in vitro study, impressions were made of a master maxillary arch containing three reference inserts on the occlucal surface of the left and right maxillary second molars and in the incisal surface of the maxillary central incisors. Two types of color-changing irreversible hydrocolloid (tetrachrom, cavex were used. Glutaraldehyde 2% was used in two methods of spraying and immersion to disinfect the impressions. The control group was not disinfected. Casts were made of type IV gypsum. The linear dimensional change of the stone casts was measured with a profile projector. For statistical analysis, Kruskall-Wallis and Mann-Witney tests were used (α=0.05. Results: By immersion method, the casts fabricated from tetrachrom were 0.36% larger in the anteroposterior (AP and 0.05% smaller in cross arch (CA dimensions; however, the casts prepared after spraying of tetrachrom were 0.44% larger in the AP and 0.10% smaller in CA dimensions. The casts made from Cavex were 0.05% smaller in the AP and 0.02% smaller in CA dimensions after spraying and 0.01% smaller in the AP and 0.003% smaller in CA dimensions after immersion. Generally there were not significant differences in AP and CA dimensions of the experimental groups compared to the control (p > 0.05. Conclusions: Disinfection of the tested color-changing irreversible hydrocolloids by glutaraldahyde 2% did not compromise the accuracy of the obtained casts.

  8. Determining the complex modulus of alginate irreversible hydrocolloid dental material.

    Science.gov (United States)

    King, Shalinie; See, Howard; Thomas, Graham; Swain, Michael

    2008-11-01

    The aim of the study is to investigate the visco-elastic response of an alginate irreversible hydrocolloid dental impression material during setting. A novel squeeze film Micro-Fourier Rheometer (MFR, GBC Scientific Equipment, Australia) was used to determine the complex modulus of an alginate irreversible hydrocolloid dental impression material (Algident, ISO 1563 Class A Type 1, Dentalfarm Australia Pty. Ltd.) during setting after mixing. Data was collected every 30s for 10 min in one study and every 10 min for a total of 60 min in another study. A high level of repeatability was observed. The results indicate that the MFR is capable of recording the complex shear modulus of alginate irreversible hydrocolloid for 60 min from the start of mixing and to simultaneously report the changing visco-elastic parameters at all frequencies between 1 Hz and 100 Hz. The storage modulus shows a dramatic increase to 370% of its starting value after 6 min and then reduces to 55% after 60 min. The loss modulus increases to a maximum of 175% of its starting value after 10 min and then reduces to 94% after 60 min. The MFR enables the changes in the complex modulus through the complete setting process to be followed. It is anticipated this approach may provide a better method to compare the visco-elastic properties of impression materials and assist with identification of optimum types for different clinical requirements. The high stiffness of the instrument and the use of band-limited pseudo-random noise as the input signal are the main advantages of this technique over conventional rheometers for determining the changes in alginate visco-elasticity.

  9. Extended irreversible thermodynamics and non-equilibrium temperature

    Directory of Open Access Journals (Sweden)

    Casas-Vazquez, Jose'

    2008-02-01

    Full Text Available We briefly review the concept of non-equilibrium temperature from the perspectives of extended irreversible thermodynamics, fluctuation theory, and statistical mechanics. The relations between different proposals are explicitly examined in two especially simple systems: an ideal gas in steady shear flow and a forced harmonic oscillator in a thermal bath. We examine with special detail temperatures related to the average molecular kinetic energy along different spatial directions, to the average configurational energy, to the derivative of the entropy with respect to internal energy, to fluctuation-dissipation relation and discuss their measurement.

  10. Prevention of organ rejection in renal and liver transplantation with extended release tacrolimus

    Directory of Open Access Journals (Sweden)

    Reschen ME

    2014-09-01

    Full Text Available Michael E Reschen, Christopher A O’Callaghan Henry Wellcome Building, Nuffield Department of Medicine, University of Oxford, Oxford, United Kingdom Abstract: Tacrolimus is the key immunosuppressant used to prevent allograft rejection in kidney and liver transplant recipients. Despite the efficacy of tacrolimus and adjunctive immunosuppressants, a substantial number of patients experience episodes of acute rejection and late graft loss. Nonadherence is an etiological factor in both acute rejection and graft loss. In 2007, a prolonged release version of tacrolimus became available that allows once daily administration, thus halving the pill burden compared to the standard twice-daily tacrolimus. An increasing number of studies in de novo transplantation and in treatment conversion have evaluated the pharmacokinetic profile, efficacy, and safety of prolonged-release tacrolimus. We have reviewed the literature on the use of prolonged-release tacrolimus and hope that this will be of value in the design of protocols for transplant immunosuppression.Keywords: immunosuppression, kidney, hepatic, allograft, adherence

  11. Experimental and epidemiological evidence on non-organ specific cancer preventive effect of Korean ginseng and identification of active compounds

    Energy Technology Data Exchange (ETDEWEB)

    Yun, T.-K

    2003-03-01

    Panax ginseng C.A. Meyer has been the most highly recognized medicinal herb in the Orient. The prolonged administration of red ginseng extract significantly inhibits the incidence of hepatoma and also proliferation of pulmonary tumors induced by aflatoxin B{sub 1} and urethane. Statistically significant anticarcinogenic effects were in aged or heat treated extracts of ginseng and red ginseng made by steaming in a 9 weeks medium-term anticarcinogenicity test using benzo[a]pyrene. In case-control studies, odds ratios (OR) of the cancer of lip, oral cavity and pharynx, larynx, lung, esophagus, stomach, liver, pancreas, ovary, and colorectum were significantly reduced. As to the type of ginseng, the ORs for cancer were reduced in user of fresh ginseng extract intakers, white ginseng extract, white ginseng powder, and red ginseng. In a cohort study with 5 years follow-up conducted in a ginseng cultivation area, ginseng users had a decreased relative risk (RR) compared with non-users. The relative risks (RRs) of ginseng users were decreased in gastric cancer and lung cancer. These findings strongly suggest that Panax ginseng C.A. Meyer cultivated in Korea has non-organ specific cancer preventive effects against various cancers. To investigate the active components for cancer prevention, several fractions of fresh and red ginseng and four semi-synthetic ginsenoside Rh{sub 1}, Rh{sub 2}, Rg{sub 3} and Rg{sub 5}, the major saponin components in red ginseng, were prepared among the ginsenosides. By using Yun's model, Rg{sub 3} and Rg{sub 5} showed statistically significant reduction of lung tumor incidence and Rh{sub 2} had a tendency to decrease the incidence. In conclusion, these results strongly suggested that Panax ginseng C.A. Meyer cultivated in Korea is a non-organ specific cancer preventive against human cancers and also indicated that the anticarcinogenicity or human cancer preventive effect of Panax ginseng is due to ginsenoside Rg{sub 3}, Rg{sub 5} and Rh

  12. [Slowing down the rate of irreversible age-related atrophy of the thymus gland by atopic autotransplantation of its tissue, subjected to long-term cryoconservation].

    Science.gov (United States)

    Kulikov, A V; Arkhipova, L V; Smirnova, G N; Novoselova, E G; Shpurova, N A; Shishova, N V; Sukhikh, G T

    2010-01-01

    An experimental procedure has been developed enabling to slow down the rate of irreversible atrophy of the thymus gland. The atopic autotransplantation of its tissue subjected to prolonged cryoconservation enables one to inhibit the aging of the organism with respect to several biochemical and immunological indicators.

  13. Kynurenine-3-monooxygenase inhibition prevents multiple organ failure in rodent models of acute pancreatitis.

    Science.gov (United States)

    Mole, Damian J; Webster, Scott P; Uings, Iain; Zheng, Xiaozhong; Binnie, Margaret; Wilson, Kris; Hutchinson, Jonathan P; Mirguet, Olivier; Walker, Ann; Beaufils, Benjamin; Ancellin, Nicolas; Trottet, Lionel; Bénéton, Véronique; Mowat, Christopher G; Wilkinson, Martin; Rowland, Paul; Haslam, Carl; McBride, Andrew; Homer, Natalie Z M; Baily, James E; Sharp, Matthew G F; Garden, O James; Hughes, Jeremy; Howie, Sarah E M; Holmes, Duncan S; Liddle, John; Iredale, John P

    2016-02-01

    Acute pancreatitis (AP) is a common and devastating inflammatory condition of the pancreas that is considered to be a paradigm of sterile inflammation leading to systemic multiple organ dysfunction syndrome (MODS) and death. Acute mortality from AP-MODS exceeds 20% (ref. 3), and the lifespans of those who survive the initial episode are typically shorter than those of the general population. There are no specific therapies available to protect individuals from AP-MODS. Here we show that kynurenine-3-monooxygenase (KMO), a key enzyme of tryptophan metabolism, is central to the pathogenesis of AP-MODS. We created a mouse strain that is deficient for Kmo (encoding KMO) and that has a robust biochemical phenotype that protects against extrapancreatic tissue injury to the lung, kidney and liver in experimental AP-MODS. A medicinal chemistry strategy based on modifications of the kynurenine substrate led to the discovery of the oxazolidinone GSK180 as a potent and specific inhibitor of KMO. The binding mode of the inhibitor in the active site was confirmed by X-ray co-crystallography at 3.2 Å resolution. Treatment with GSK180 resulted in rapid changes in the levels of kynurenine pathway metabolites in vivo, and it afforded therapeutic protection against MODS in a rat model of AP. Our findings establish KMO inhibition as a novel therapeutic strategy in the treatment of AP-MODS, and they open up a new area for drug discovery in critical illness.

  14. Becoming a first-class noticer. How to spot and prevent ethical failures in your organization.

    Science.gov (United States)

    Bazerman, Max H

    2014-01-01

    We'd like to think that no smart, upstanding manager would ever overlook or turn a blind eye to threats or wrongdoing that ultimately imperil his or her business. Yet it happens all the time. We fall prey to obstacles that obscure or drown out important signals that things are amiss. Becoming a "first-class noticer," says Max H. Bazerman, a professor at Harvard Business School, requires conscious effort to fight ambiguity, motivated blindness, conflicts of interest, the slippery slope, and efforts of others to mislead us. As a manager, you can develop your noticing skills by acknowledging responsibility when things go wrong rather than blaming external forces beyond your control. Bazerman also advises taking an outsider's view to challenge the status quo. Given the string of ethical failures of corporations around the world in recent years--from BP to GM to JP Morgan Chase--it's clear that leaders not only need to act more responsibly themselves but also must develop keen noticing skills in their employees and across their organizations.

  15. IRREVERSIBILITY GENERATION IN SUGAR, ALCOHOL AND BIOGAS INTEGRATED PRODUCTIONS

    Directory of Open Access Journals (Sweden)

    Meilyn González Cortés

    2017-01-01

    Full Text Available In this work, the stages of losses and lower exergetic efficiency are determined when the sugar production process is integrated with others for the production of products such as biogas, torula yeast and electricity. The study is carried out in three scenarios of integrated processes for obtaining the indicated products. A sugar factory in which sugar and electricity are produced is considered as the base scenario and from this; a second scenario is inferred in which alcohol is produced from the molasses of the sugar process and biogas from the vinasse of the alcohol distillation process. Finally, a third scenario is exergetically evaluated in which sugar, electricity, biogas and alcohol are produced, but this last one from juices and molasses of the sugar process. For the exergetic analysis the integrated scheme was divided into 8 subsystems. From the analysis of results, the major subsystems that generate irreversibilities are: cogeneration (64.36-65.98%, juice extraction (8.85-9.85%, crystallization and cooking, (8.48 -9.02%, fermentation (4.12-4.94% and distillation (2.74-3.2%. Improvements are proposed to minimize irreversibilities, including the thermal integration of processes, technological modifications in the fermentation process and the introduction of more efficient equipment for the generation of electricity. The exergetic efficiency is between 78.95-81.10%, obtaining greater exergetic efficiency in the scheme of joint operation to produce sugar, alcohol and biogas.

  16. Irreversible entropy model for damage diagnosis in resistors

    International Nuclear Information System (INIS)

    Cuadras, Angel; Crisóstomo, Javier; Ovejas, Victoria J.; Quilez, Marcos

    2015-01-01

    We propose a method to characterize electrical resistor damage based on entropy measurements. Irreversible entropy and the rate at which it is generated are more convenient parameters than resistance for describing damage because they are essentially positive in virtue of the second law of thermodynamics, whereas resistance may increase or decrease depending on the degradation mechanism. Commercial resistors were tested in order to characterize the damage induced by power surges. Resistors were biased with constant and pulsed voltage signals, leading to power dissipation in the range of 4–8 W, which is well above the 0.25 W nominal power to initiate failure. Entropy was inferred from the added power and temperature evolution. A model is proposed to understand the relationship among resistance, entropy, and damage. The power surge dissipates into heat (Joule effect) and damages the resistor. The results show a correlation between entropy generation rate and resistor failure. We conclude that damage can be conveniently assessed from irreversible entropy generation. Our results for resistors can be easily extrapolated to other systems or machines that can be modeled based on their resistance

  17. Voter model with arbitrary degree dependence: clout, confidence and irreversibility

    Science.gov (United States)

    Fotouhi, Babak; Rabbat, Michael G.

    2014-03-01

    The voter model is widely used to model opinion dynamics in society. In this paper, we propose three modifications to incorporate heterogeneity into the model. We address the corresponding oversimplifications of the conventional voter model which are unrealistic. We first consider the voter model with popularity bias. The influence of each node on its neighbors depends on its degree. We find the consensus probabilities and expected consensus times for each of the states. We also find the fixation probability, which is the probability that a single node whose state differs from every other node imposes its state on the entire system. In addition, we find the expected fixation time. Then two other extensions to the model are proposed and the motivations behind them are discussed. The first one is confidence, where in addition to the states of neighbors, nodes take their own state into account at each update. We repeat the calculations for the augmented model and investigate the effects of adding confidence to the model. The second proposed extension is irreversibility, where one of the states is given the property that once nodes adopt it, they cannot switch back. This is motivated by applications where, agents take an irreversible action such as seeing a movie, purchasing a music album online, or buying a new product. The dynamics of densities, fixation times and consensus times are obtained.

  18. Influence of delayed pouring on irreversible hydrocolloid properties

    Directory of Open Access Journals (Sweden)

    Stéfani Becker Rodrigues

    2012-10-01

    Full Text Available The aim of this study was to evaluate the physical properties of irreversible hydrocolloid materials poured immediately and after different storage periods. Four alginates were tested: Color Change (Cavex; Hydrogum (Zhermack; Hydrogum 5 (Zhermack; and Hydro Print Premium (Coltene. Their physical properties, including the recovery from deformation (n = 3, compressive strength (n = 3, and detail reproduction and gypsum compatibility (n = 3, were analyzed according to ANSI/ADA specification no. 18. Specimens were stored at 23ºC and humidity and were then poured with gypsum immediately and after 1, 2, 3, 4, and 5 days. The data were analyzed by two-way analysis of variance (ANOVA and Tukey's test at p < 0.05. All of the alginate impression materials tested exhibited detail reproduction and gypsum compatibility at all times. Hydro Print Premium and Hydrogum 5 showed recovery from deformation, as established by ANSI/ADA specification no. 18, after 5 days of storage. As the storage time increased, the compressive strength values also increased. Considering the properties of compounds' recovery from deformation, compressive strength, and detail reproduction and gypsum compatibility, irreversible hydrocolloids should be poured immediately.

  19. Advanced Caries Microbiota in Teeth with Irreversible Pulpitis.

    Science.gov (United States)

    Rôças, Isabela N; Lima, Kenio C; Assunção, Isauremi V; Gomes, Patrícia N; Bracks, Igor V; Siqueira, José F

    2015-09-01

    Bacterial taxa in the forefront of caries biofilms are candidate pathogens for irreversible pulpitis and are possibly the first ones to invade the pulp and initiate endodontic infection. This study examined the microbiota of the most advanced layers of dentinal caries in teeth with irreversible pulpitis. DNA extracted from samples taken from deep dentinal caries associated with pulp exposures was analyzed for the presence and relative levels of 33 oral bacterial taxa by using reverse-capture checkerboard hybridization assay. Quantification of total bacteria, streptococci, and lactobacilli was also performed by using real-time quantitative polymerase chain reaction. Associations between the target bacterial taxa and clinical signs/symptoms were also evaluated. The most frequently detected taxa in the checkerboard assay were Atopobium genomospecies C1 (53%), Pseudoramibacter alactolyticus (37%), Streptococcus species (33%), Streptococcus mutans (33%), Parvimonas micra (13%), Fusobacterium nucleatum (13%), and Veillonella species (13%). Streptococcus species, Dialister invisus, and P. micra were significantly associated with throbbing pain, S. mutans with pain to percussion, and Lactobacillus with continuous pain (P pulpitis is suspected. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  20. Identification and Characterization of an Irreversible Inhibitor of CDK2.

    Science.gov (United States)

    Anscombe, Elizabeth; Meschini, Elisa; Mora-Vidal, Regina; Martin, Mathew P; Staunton, David; Geitmann, Matthis; Danielson, U Helena; Stanley, Will A; Wang, Lan Z; Reuillon, Tristan; Golding, Bernard T; Cano, Celine; Newell, David R; Noble, Martin E M; Wedge, Stephen R; Endicott, Jane A; Griffin, Roger J

    2015-09-17

    Irreversible inhibitors that modify cysteine or lysine residues within a protein kinase ATP binding site offer, through their distinctive mode of action, an alternative to ATP-competitive agents. 4-((6-(Cyclohexylmethoxy)-9H-purin-2-yl)amino)benzenesulfonamide (NU6102) is a potent and selective ATP-competitive inhibitor of CDK2 in which the sulfonamide moiety is positioned close to a pair of lysine residues. Guided by the CDK2/NU6102 structure, we designed 6-(cyclohexylmethoxy)-N-(4-(vinylsulfonyl)phenyl)-9H-purin-2-amine (NU6300), which binds covalently to CDK2 as shown by a co-complex crystal structure. Acute incubation with NU6300 produced a durable inhibition of Rb phosphorylation in SKUT-1B cells, consistent with it acting as an irreversible CDK2 inhibitor. NU6300 is the first covalent CDK2 inhibitor to be described, and illustrates the potential of vinyl sulfones for the design of more potent and selective compounds. Copyright © 2015 The Authors. Published by Elsevier Ltd.. All rights reserved.

  1. Complications of Transvaginal Mesh for Pelvic Organ Prolapse and Stress Urinary Incontinence: Tips for Prevention, Recognition, and Management.

    Science.gov (United States)

    MacDonald, Susan; Terlecki, Ryan; Costantini, Elisabetta; Badlani, Gopal

    2016-08-01

    Mesh-related complications following transvaginal management of pelvic organ prolapse (POP) and/or stress urinary incontinence (SUI) have received significant attention in the last decade. We sought to identify patient, product, and technical factors associated with an increased risk of complications after mesh-based transvaginal repair of anterior POP and SUI. In this review we clarify the different pattern of complications after POP and SUI repairs. Our aim is to provide a practical evidence-based guide for physicians to prevent and, if necessary, manage product-associated complications in a stepwise manner. We conducted a comprehensive PubMed search of all English-language articles published from 2010 to June 2016, using these search terms: mesh, pelvic organ prolapse, and stress urinary incontinence. Expert opinion is also provided. Mesh-related complications are much lower after repair of SUI compared with POP, despite its more frequent use. Vaginal exposure is the most common mesh-specific complication. Patients may present with vaginal discharge, dyspareunia, pain, recurrent urinary tract infection, and/or hematuria. Conversely, patients may be asymptomatic. Small asymptomatic mesh exposures (urinary tract must be fully excised. Following excision, pain may persist in up to 50% of patients. Vaginal extrusion, persistent pain, and urethral and/or bladder erosion are the three most common product-specific complications following mesh-based repair for SUI or POP. Conservative therapies may be attempted, but most patients ultimately require partial or complete mesh excision. We reviewed the recent literature on mesh-related complications after repair of pelvic organ prolapse (POP) and stress urinary incontinence (SUI). Vaginal exposure, persistent pain, and erosion into the urinary tract are the most common. These often require surgical management, best suited to a urologist with training and experience in this area. Evidence supports mesh use for correction of

  2. Advertising and Irreversible Opinion Spreading in Complex Social Networks

    Science.gov (United States)

    Candia, Julián

    Irreversible opinion spreading phenomena are studied on small-world and scale-free networks by means of the magnetic Eden model, a nonequilibrium kinetic model for the growth of binary mixtures in contact with a thermal bath. In this model, the opinion of an individual is affected by those of their acquaintances, but opinion changes (analogous to spin flips in an Ising-like model) are not allowed. We focus on the influence of advertising, which is represented by external magnetic fields. The interplay and competition between temperature and fields lead to order-disorder transitions, which are found to also depend on the link density and the topology of the complex network substrate. The effects of advertising campaigns with variable duration, as well as the best cost-effective strategies to achieve consensus within different scenarios, are also discussed.

  3. Irreversibility of world-sheet renormalization group flow

    International Nuclear Information System (INIS)

    Oliynyk, T.; Suneeta, V.; Woolgar, E.

    2005-01-01

    We demonstrate the irreversibility of a wide class of world-sheet renormalization group (RG) flows to first order in α ' in string theory. Our techniques draw on the mathematics of Ricci flows, adapted to asymptotically flat target manifolds. In the case of somewhere-negative scalar curvature (of the target space), we give a proof by constructing an entropy that increases monotonically along the flow, based on Perelman's Ricci flow entropy. One consequence is the absence of periodic solutions, and we are able to give a second, direct proof of this. If the scalar curvature is everywhere positive, we instead construct a regularized volume to provide an entropy for the flow. Our results are, in a sense, the analogue of Zamolodchikov's c-theorem for world-sheet RG flows on noncompact spacetimes (though our entropy is not the Zamolodchikov C-function)

  4. Irreversible work and inner friction in quantum thermodynamic processes.

    Science.gov (United States)

    Plastina, F; Alecce, A; Apollaro, T J G; Falcone, G; Francica, G; Galve, F; Lo Gullo, N; Zambrini, R

    2014-12-31

    We discuss the thermodynamics of closed quantum systems driven out of equilibrium by a change in a control parameter and undergoing a unitary process. We compare the work actually done on the system with the one that would be performed along ideal adiabatic and isothermal transformations. The comparison with the latter leads to the introduction of irreversible work, while that with the former leads to the introduction of inner friction. We show that these two quantities can be treated on an equal footing, as both can be linked with the heat exchanged in thermalization processes and both can be expressed as relative entropies. Furthermore, we show that a specific fluctuation relation for the entropy production associated with the inner friction exists, which allows the inner friction to be written in terms of its cumulants.

  5. Structural transition models for a class or irreversible aggregates

    International Nuclear Information System (INIS)

    Canessa, E.

    1995-02-01

    A progress report on two recent theoretical approaches proposed to understand the physics of irreversible fractal aggregates showing up a structural transition from a rather dense to a more multibranched growth is presented. In the first approach the transition is understood by solving the Poisson equation on a squared lattice. The second approach is based on the discretization of the Biharmonic equation. Within these models the transition appears when the growth velocity at the fractal surface presents a minimum. The effects of the surrounding medium and geometrical constraints for the seed particles are considered. By using the optical diffraction method, the structural transition is further characterized by a decrease in the fractal dimension for this peculiar class of aggregates. (author). 17 refs, 4 figs

  6. Thermodynamic Optimality criteria for biological systems in linear irreversible thermodynamics

    International Nuclear Information System (INIS)

    Chimal, J C; Sánchez, N; Ramírez, PR

    2017-01-01

    In this paper the methodology of the so-called Linear Irreversible Thermodynamics (LIT) is applied; although traditionally used locally to study general systems in non-equilibrium states in which it is consider both internal and external contributions to the entropy increments in order to analyze the efficiency of two coupled processes with generalized fluxes J 1 , J 2 and their corresponding forces X 1 , X 2 . We extend the former analysis to takes into account two different operating regimes namely: Omega Function and Efficient Power criterion, respectively. Results show analogies in the optimal performance between and we can say that there exist a criteria of optimization which can be used specially for biological systems where a good design of the biological parameters made by nature at maximum efficient power conditions lead to more efficient engines than those at the maximum power conditions or ecological conditions. (paper)

  7. The Social Cost of Stochastic and Irreversible Climate Change

    Science.gov (United States)

    Cai, Y.; Judd, K. L.; Lontzek, T.

    2013-12-01

    Many scientists are worried about climate change triggering abrupt and irreversible events leading to significant and long-lasting damages. For example, a rapid release of methane from permafrost may lead to amplified global warming, and global warming may increase the frequency and severity of heavy rainfall or typhoon, destroying large cities and killing numerous people. Some elements of the climate system which might exhibit such a triggering effect are called tipping elements. There is great uncertainty about the impact of anthropogenic carbon and tipping elements on future economic wellbeing. Any rational policy choice must consider the great uncertainty about the magnitude and timing of global warming's impact on economic productivity. While the likelihood of tipping points may be a function of contemporaneous temperature, their effects are long lasting and might be independent of future temperatures. It is assumed that some of these tipping points might occur even in this century, but also that their duration and post-tipping impact are uncertain. A faithful representation of the possibility of tipping points for the calculation of social cost of carbon would require a fully stochastic formulation of irreversibility, and accounting for the deep layer of uncertainties regarding the duration of the tipping process and also its economic impact. We use DSICE, a DSGE extension of the DICE2007 model of William Nordhaus, which incorporates beliefs about the uncertain economic impact of possible climate tipping events and uses empirically plausible parameterizations of Epstein-Zin preferences to represent attitudes towards risk. We find that the uncertainty associated with anthropogenic climate change imply carbon taxes much higher than implied by deterministic models. This analysis indicates that the absence of uncertainty in DICE2007 and similar IAM models may result in substantial understatement of the potential benefits of policies to reduce GHG emissions.

  8. Constructal theory through thermodynamics of irreversible processes framework

    International Nuclear Information System (INIS)

    Tescari, S.; Mazet, N.; Neveu, P.

    2011-01-01

    Highlights: → Point to area flow problem is solved through Thermodynamics of irreversible processes. → A new optimisation criterion is defined: the exergy or entropy impedance. → Optimisation is performed following two different routes, constructal or global. → Global optimisation is more efficient than constructal optimisation. → Global optimisation enhances the domain of construct benefits. - Abstract: Point to volume flow problem is revisited on a thermodynamics of irreversible processes (TIP) basis. The first step consists in evaluating the local entropy production of the system, and deducing from this expression the phenomenological laws. Then, the total entropy production can be simply evaluated. It is demonstrated that total entropy production can be written in a remarkable form: the product of the so-called entropy impedance with the square of the heat flux. As the heat flux is given, optimisation consists in minimising the entropy impedance. It is also shown that minimising entropy impedance minimises the maximum temperature difference. Applied to the elemental volume, this optimisation process leads to a shape factor close to the one already published. For the first construction, the equivalent system is defined as stated by Prigogine: when subjected to the same constraints, two systems are thermodynamically equivalent if their entropy production is equal. Two optimisation routes are then investigated: a global optimisation where all scales are taken into account and the constructal optimisation where the system is optimised scale by scale. In this second case, results are close to Ghodossi's work. When global optimisation is performed, it is demonstrated that conductive paths have to be spread uniformly in the active material (i.e. the number of elemental volumes must go to infinite). Comparing the two routes, global optimisation leads to better performance than constructal optimisation. Moreover, global optimisation enlarges the domain of

  9. Health Technology Assessment of CEM Pulpotomy in Permanent Molars with Irreversible Pulpitis

    OpenAIRE

    Yazdani, Shahram; Jadidfard, Mohammad-Pooyan; Tahani, Bahareh; Kazemian, Ali; Dianat, Omid; Alim Marvasti, Laleh

    2013-01-01

    Introduction: Teeth with irreversible pulpitis usually undergo root canal therapy (RCT). This treatment modality is often considered disadvantageous as it removes vital pulp tissue and weakens the tooth structure. A relatively new concept has risen which suggests vital pulp therapy (VPT) for irreversible pulpitis. VPT with calcium enriched mixture (VPT/CEM) has demonstrated favorable treatment outcomes when treating permanent molars with irreversible pulpitis. This study aims to compare patie...

  10. Antifouling coatings: recent developments in the design of surfaces that prevent fouling by proteins, bacteria, and marine organisms.

    Science.gov (United States)

    Banerjee, Indrani; Pangule, Ravindra C; Kane, Ravi S

    2011-02-08

    The major strategies for designing surfaces that prevent fouling due to proteins, bacteria, and marine organisms are reviewed. Biofouling is of great concern in numerous applications ranging from biosensors to biomedical implants and devices, and from food packaging to industrial and marine equipment. The two major approaches to combat surface fouling are based on either preventing biofoulants from attaching or degrading them. One of the key strategies for imparting adhesion resistance involves the functionalization of surfaces with poly(ethylene glycol) (PEG) or oligo(ethylene glycol). Several alternatives to PEG-based coatings have also been designed over the past decade. While protein-resistant coatings may also resist bacterial attachment and subsequent biofilm formation, in order to overcome the fouling-mediated risk of bacterial infection it is highly desirable to design coatings that are bactericidal. Traditional techniques involve the design of coatings that release biocidal agents, including antibiotics, quaternary ammonium salts (QAS), and silver, into the surrounding aqueous environment. However, the emergence of antibiotic- and silver-resistant pathogenic strains has necessitated the development of alternative strategies. Therefore, other techniques based on the use of polycations, enzymes, nanomaterials, and photoactive agents are being investigated. With regard to marine antifouling coatings, restrictions on the use of biocide-releasing coatings have made the generation of nontoxic antifouling surfaces more important. While considerable progress has been made in the design of antifouling coatings, ongoing research in this area should result in the development of even better antifouling materials in the future. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Irreversible electroporation of locally advanced solid pseudopapillary carcinoma of the pancreas: A case report

    Directory of Open Access Journals (Sweden)

    Luciano Tarantino

    2018-04-01

    Full Text Available Introduction: Solid pseudopapillary Carcinoma (SPC is a rare pancreatic Tumor with variable, usually low, malignancy potential. Howewer, several SPC are associated with aggressive behavior, local vascular infiltration, organ invasion, distant metastasis, and can be unresectable. Irreversible Electroporation (IRE is an emerging non-thermal ablation technique for the treatment of locally advanced pancreatic carcinoma. We report the results of four year disease-free follow-up in a case of locally advanced unresectable SPC treated with IRE. Presentation of case: A 24-year female patient with SPC of the pancreas underwent IRE during laparotomy under general anesthesia with intubation. Computed Tomography (CT showed complete tumor thrombosis of splenic vein, encasement of celiac artery and mesenteric vein. Six insertions of 3–4 electrodes per insertion were performed. One month-CT-control showed shrinkage of the tumor. 6 months-post-treatment imaging showed complete regression of the mass, patent Splenic/mesenteric veins, absence of local recurrence or distant metastasis. Post treatment CTs at 12-18-24-30-36-42-48 months follow-up confirmed absence of local or distant recurrence. Discussion: Surgery is the first choice curative treatment of SPC. Howewer aggressive surgery (duodeno-pancreasectomy in unresectable cases, may have a high risk of recurrences, morbidities and death, and bring concerns about endocrine and exocrine insufficiency in a young patient. In these cases, IRE could be a safe and effective alternative treatment and could realize, in selected cases, the condition for a radical surgery, and a bridge to R-0 resection. Conclusions: IRE could represent an effective alternative therapy to surgery in local advanced, unresectable SPC. Keywords: Pancreatic neoplasm, Solid papillary carcinoma, Intraoperative ultrasound, Irreversible electroporation, Case report

  12. Near-neutral surface charge and hydrophilicity prevent mineral encrustation of Fe-oxidizing micro-organisms.

    Science.gov (United States)

    Saini, G; Chan, C S

    2013-03-01

    Microbial survival in mineralizing environments depends on the ability to evade surface encrustation by minerals, which could obstruct nutrient uptake and waste output. Some organisms localize mineral precipitation away from the cell; however, cell surface properties - charge and hydrophobicity - must also play a role in preventing surface mineralization. This is especially relevant for iron-oxidizing bacteria (FeOB), which face an encrustation threat from both biotic and abiotic mineralization. We used electron microscopy and surface characterization techniques to study the surfaces of two stalk-forming neutrophilic FeOB: the marine Zetaproteobacterium Mariprofundus ferrooxydans PV-1 and the recently isolated freshwater Betaproteobacterium Gallionellales strain R-1. Both organisms lack detectable iron on cell surfaces. Live and azide-inhibited M. ferrooxydans PV-1 cells had small negative zeta potentials (-0.34 to -2.73 mV), over the pH range 4.2-9.4; Gallionellales strain R-1 cells exhibited an even smaller zeta potential (-0.10 to -0.19 mV) over pH 4.2-8.8. Cells have hydrophilic surfaces, according to water contact angle measurements and microbial adhesion to hydrocarbons tests. Thermodynamic and extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) calculations showed that as low charge causes low electrostatic attraction, hydrophilic repulsion dominates cell-mineral interactions. Therefore, we conclude that surface properties help enable these FeOB to survive in highly mineralizing environments. Given both mineral-repelling surface properties and the ability to sequester Fe(III) biominerals in an organomineral stalk, these two FeOB have a well-coordinated system to localize both biotic and abiotic mineral distribution. © 2012 Blackwell Publishing Ltd.

  13. Organics.

    Science.gov (United States)

    Chian, Edward S. K.; DeWalle, Foppe B.

    1978-01-01

    Presents water analysis literature for 1978. This review is concerned with organics, and it covers: (1) detergents and surfactants; (2) aliphatic and aromatic hydrocarbons; (3) pesticides and chlorinated hydrocarbons; and (4) naturally occurring organics. A list of 208 references is also presented. (HM)

  14. Organizers.

    Science.gov (United States)

    Callison, Daniel

    2000-01-01

    Focuses on "organizers," tools or techniques that provide identification and classification along with possible relationships or connections among ideas, concepts, and issues. Discusses David Ausubel's research and ideas concerning advance organizers; the implications of Ausubel's theory to curriculum and teaching; "webbing," a…

  15. ESTIMATION OF IRREVERSIBLE DAMAGEABILITY AT FATIGUE OF CARBON STEEL

    Directory of Open Access Journals (Sweden)

    I. O. Vakulenko

    2014-04-01

    Full Text Available Purpose. Damageability estimation of carbon steel in the conditions of cyclic loading. Methodology. The steel fragments of railway wheel rim and rail head served as material for research with chemical composition 0.65 % С, 0.67 % Mn, 0.3 % Si, 0.027 % P, 0.028 % S и 0.7 % C, 0.82 % Mn, 0.56 % Si, 0.025 % P, 0.029 % S accordingly. The microstructure of tested steels corresponded to the state of metal after a hot plastic deformation. The fatigue research was conducted in the conditions of symmetric bend using the proof-of-concept machine of type «Saturn-10». Full Wohler diagrams and the lines corresponding to forming of sub-and micro cracks were constructed. The distribution analysis of internal stresses in the metal under cyclic loading was carried out using the microhardness tester of PMT-3 type.Findings. On the basis of fatigue curves for high-carbon steels analysis the positions of borders dividing the areas of convertible and irreversible damages were determined. The article shows that with the growth of carbon concentration in the steel at invariability of the structural state an increase of fatigue limit is observed. At the same time the acceleration of processes, which determine transition terms from the stage of forming of submicrocracks to the microcracks occurs. The research of microhardness distribution in the metal after destruction confirmed the nature of carbon amount influence on the carbon steel characteristics. Originality. Regardless on the stages of breakdown site forming the carbon steels behavior at a fatigue is determined by the ration between the processes of strengthening and softening. At a cyclic loading the heterogeneity of internal stresses distribution decreases with the increase of distance from the destruction surface. Analysis of metal internal restructuring processes at fatigue loading made it possible to determine that at the stages prior to incubation period in the metal microvolumes the cells are already

  16. Irreversible block of cardiac mutant Na+ channels by batrachotoxin.

    Science.gov (United States)

    Wang, Sho-Ya; Tikhonov, Denis B; Mitchell, Jane; Zhorov, Boris S; Wang, Ging Kuo

    2007-01-01

    Batrachotoxin (BTX) not only keeps the voltage-gated Na(+) channel open persistently but also reduces its single-channel conductance. Although a BTX receptor has been delimited within the inner cavity of Na(+) channels, how Na(+) ions flow through the BTX-bound permeation pathway remains unclear. In this report we tested a hypothesis that Na(+) ions traverse a narrow gap between bound BTX and residue N927 at D2S6 of cardiac hNa(v)1.5 Na(+) channels. We found that BTX at 5 microM indeed elicited a strong block of hNa(v)1.5-N927K currents (approximately 70%) after 1000 repetitive pulses (+50 mV/20 ms at 2 Hz) without any effects on Na(+) channel gating. Once occurred, this unique use-dependent block of hNa(v)1.5-N927K Na(+) channels recovered little at holding potential (-140 mV), demonstrating that BTX block is irreversible under our experimental conditions. Such an irreversible effect likewise developed in fast inactivation-deficient hNa(v)1.5-N927K Na(+) channels albeit with a faster on-rate; approximately 90% of peak Na(+) currents were abolished by BTX after 200 repetitive pulses (+50 mV/20 ms). This use-dependent block of fast inactivation-deficient hNa(v)1.5-N927K Na(+) channels by BTX was duration dependent. The longer the pulse duration the larger the block developed. Among N927K/W/R/H/D/S/Q/G/E substitutions in fast inactivation-deficient hNa(v)1.5 Na(+) channels, only N927K/R Na(+) currents were highly sensitive to BTX block. We conclude that (a) BTX binds within the inner cavity and partly occludes the permeation pathway and (b) residue hNa(v)1.5-N927 is critical for ion permeation between bound BTX and D2S6, probably because the side-chain of N927 helps coordinate permeating Na(+) ions.

  17. Multiscale Analysis of Time Irreversibility Based on Phase-Space Reconstruction and Horizontal Visibility Graph Approach

    Science.gov (United States)

    Zhang, Yongping; Shang, Pengjian; Xiong, Hui; Xia, Jianan

    Time irreversibility is an important property of nonequilibrium dynamic systems. A visibility graph approach was recently proposed, and this approach is generally effective to measure time irreversibility of time series. However, its result may be unreliable when dealing with high-dimensional systems. In this work, we consider the joint concept of time irreversibility and adopt the phase-space reconstruction technique to improve this visibility graph approach. Compared with the previous approach, the improved approach gives a more accurate estimate for the irreversibility of time series, and is more effective to distinguish irreversible and reversible stochastic processes. We also use this approach to extract the multiscale irreversibility to account for the multiple inherent dynamics of time series. Finally, we apply the approach to detect the multiscale irreversibility of financial time series, and succeed to distinguish the time of financial crisis and the plateau. In addition, Asian stock indexes away from other indexes are clearly visible in higher time scales. Simulations and real data support the effectiveness of the improved approach when detecting time irreversibility.

  18. Fundamental economic irreversibilities influence policies for enhancing international forest phytosanitary security

    Science.gov (United States)

    Thomas P. Holmes; Will Allen; Robert G. Haight; E. Carina H. Keskitalo; Mariella Marzano; Maria Pettersson; Christopher P. Quine; E. R. Langer

    2017-01-01

    National and international efforts to manage forest biosecurity create tension between opposing sources of ecological and economic irreversibility. Phytosanitary policies designed to protect national borders from biological invasions incur sunk costs deriving from economic and political irreversibilities that incentivizes wait-and-see decision-making. However, the...

  19. Phase control of light amplification with dynamically irreversible pathways of population transfer in a Λ system

    International Nuclear Information System (INIS)

    Yuan Shi; Wu Jinhui; Gao Jinyue; Pan Chunliu

    2002-01-01

    We use the relative phase of two coherent fields for the control of light amplification with dynamically irreversible pathways of population transfer in a Λ system. The population inversion and gain with dynamically irreversible pathways of population transfer are shown as the relative phase is varied. We support our results by numerical calculation and analytical explanation

  20. A minimal dissipation type-based classification in irreversible thermodynamics and microeconomics

    Science.gov (United States)

    Tsirlin, A. M.; Kazakov, V.; Kolinko, N. A.

    2003-10-01

    We formulate the problem of finding classes of kinetic dependencies in irreversible thermodynamic and microeconomic systems for which minimal dissipation processes belong to the same type. We show that this problem is an inverse optimal control problem and solve it. The commonality of this problem in irreversible thermodynamics and microeconomics is emphasized.

  1. Factors Influencing the Implementation of Organized Physical Activity and Fruit and Vegetable Snacks in the HOP'N After-School Obesity Prevention Program

    Science.gov (United States)

    Hastmann, Tanis J.; Bopp, Melissa; Fallon, Elizabeth A.; Rosenkranz, Richard R.; Dzewaltowski, David A.

    2013-01-01

    Objective: To identify barriers and facilitators for improving the after-school organized physical activity (PA) and snack quality. Methods: After-school staff (Year 1, n = 20; Year 2, n = 17) participated in qualitative, semistructured interviews about the implementation of an after-school obesity prevention intervention. Interviews were…

  2. Organizations

    DEFF Research Database (Denmark)

    Hatch, Mary Jo

    Most of us recognize that organizations are everywhere. You meet them on every street corner in the form of families and shops, study in them, work for them, buy from them, pay taxes to them. But have you given much thought to where they came from, what they are today, and what they might become...... and considers many more. Mary Jo Hatch introduces the concept of organizations by presenting definitions and ideas drawn from the a variety of subject areas including the physical sciences, economics, sociology, psychology, anthropology, literature, and the visual and performing arts. Drawing on examples from...... prehistory and everyday life, from the animal kingdom as well as from business, government, and other formal organizations, Hatch provides a lively and thought provoking introduction to the process of organization....

  3. Organizations

    DEFF Research Database (Denmark)

    Hatch, Mary Jo

    and considers many more. Mary Jo Hatch introduces the concept of organizations by presenting definitions and ideas drawn from the a variety of subject areas including the physical sciences, economics, sociology, psychology, anthropology, literature, and the visual and performing arts. Drawing on examples from......Most of us recognize that organizations are everywhere. You meet them on every street corner in the form of families and shops, study in them, work for them, buy from them, pay taxes to them. But have you given much thought to where they came from, what they are today, and what they might become...... prehistory and everyday life, from the animal kingdom as well as from business, government, and other formal organizations, Hatch provides a lively and thought provoking introduction to the process of organization....

  4. Fuel starvation. Irreversible degradation mechanisms in PEM fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Rangel, Carmen M.; Silva, R.A.; Travassos, M.A.; Paiva, T.I.; Fernandes, V.R. [LNEG, National Laboratory for Energy and Geology, Lisboa (Portugal). UPCH Fuel Cells and Hydrogen Unit

    2010-07-01

    PEM fuel cell operates under very aggressive conditions in both anode and cathode. Failure modes and mechanism in PEM fuel cells include those related to thermal, chemical or mechanical issues that may constrain stability, power and lifetime. In this work, the case of fuel starvation is examined. The anode potential may rise to levels compatible with the oxidization of water. If water is not available, oxidation of the carbon support will accelerate catalyst sintering. Diagnostics methods used for in-situ and ex-situ analysis of PEM fuel cells are selected in order to better categorize irreversible changes of the cell. Electrochemical Impedance Spectroscopy (EIS) is found instrumental in the identification of fuel cell flooding conditions and membrane dehydration associated to mass transport limitations / reactant starvation and protonic conductivity decrease, respectively. Furthermore, it indicates that water electrolysis might happen at the anode. Cross sections of the membrane catalyst and gas diffusion layers examined by scanning electron microscopy indicate electrode thickness reduction as a result of reactions taking place during hydrogen starvation. Catalyst particles are found to migrate outwards and located on carbon backings. Membrane degradation in fuel cell environment is analyzed in terms of the mechanism for fluoride release which is considered an early predictor of membrane degradation. (orig.)

  5. Reversibility and irreversibility from an initial value formulation

    Science.gov (United States)

    Muriel, A.

    2013-07-01

    From a time evolution equation for the single particle distribution function derived from the N-particle distribution function (A. Muriel, M. Dresden, Physica D 101 (1997) 297), an exact solution for the 3D Navier-Stokes equation - an old problem - has been found (A. Muriel, Results Phys. 1 (2011) 2). In this Letter, a second exact conclusion from the above-mentioned work is presented. We analyze the time symmetry properties of a formal, exact solution for the single-particle distribution function contracted from the many-body Liouville equation. This analysis must be done because group theoretic results on time reversal symmetry of the full Liouville equation (E.C.G. Sudarshan, N. Mukunda, Classical Mechanics: A Modern Perspective, Wiley, 1974). no longer applies automatically to the single particle distribution function contracted from the formal solution of the N-body Liouville equation. We find the following result: if the initial momentum distribution is even in the momentum, the single particle distribution is reversible. If there is any asymmetry in the initial momentum distribution, no matter how small, the system is irreversible.

  6. Chemotherapy-induced irreversible alopecia in early breast cancer patients.

    Science.gov (United States)

    Kim, Gun Min; Kim, Sanghwa; Park, Hyung Seok; Kim, Jee Ye; Nam, Sanggen; Park, Seho; Kim, Seung Il; Kim, DoYoung; Sohn, Joohyuk

    2017-06-01

    The purpose of this work is to determine the prevalence of chemotherapy-induced irreversible alopecia (CIIA), which is defined as an alopecia that exists at least 6 months after completion of chemotherapy and factors affecting CIIA in early breast cancer patients. We performed a cross-sectional study. We retrospectively identified breast cancer patients who had received AC (Adriamycin, Cyclophosphamide) or AC-T (AC followed by Taxane) as neoadjuvant or adjuvant chemotherapy. We conducted questionnaire survey regarding alopecia and measured hair density using phototrichogram. From February 2015 to May 2015, among 265 patients who responded properly to the questionnaire, the women who answered they had severe alopecia (alopecia > 50% of scalp) were 19 patients (7.2%). AC-only and AC-T treated patients reported severe alopecia in 2.7% and 10.5%, respectively, which were significantly different (p < 0.001). Mean hair density was 75 hair/cm 2 (range 42-112) and 75.2/cm 2 (range 48.3-102) on occipital area and vertex area, respectively. Hair loss was the most frequent in parietal area (42.6%). Half of total patients (46%) and 73% of CIIA patients regarded that their hair became thinner after chemotherapy CONCLUSIONS: We found that significant proportion of early breast cancer patients were suffering from severe CIIA, especially when they had been treated with AC followed by taxane regimen.

  7. Reversibility and irreversibility from an initial value formulation

    International Nuclear Information System (INIS)

    Muriel, A.

    2013-01-01

    From a time evolution equation for the single particle distribution function derived from the N-particle distribution function (A. Muriel, M. Dresden, Physica D 101 (1997) 297), an exact solution for the 3D Navier–Stokes equation – an old problem – has been found (A. Muriel, Results Phys. 1 (2011) 2). In this Letter, a second exact conclusion from the above-mentioned work is presented. We analyze the time symmetry properties of a formal, exact solution for the single-particle distribution function contracted from the many-body Liouville equation. This analysis must be done because group theoretic results on time reversal symmetry of the full Liouville equation (E.C.G. Sudarshan, N. Mukunda, Classical Mechanics: A Modern Perspective, Wiley, 1974). no longer applies automatically to the single particle distribution function contracted from the formal solution of the N-body Liouville equation. We find the following result: if the initial momentum distribution is even in the momentum, the single particle distribution is reversible. If there is any asymmetry in the initial momentum distribution, no matter how small, the system is irreversible.

  8. Road deicing salt irreversibly disrupts osmoregulation of salamander egg clutches

    International Nuclear Information System (INIS)

    Karraker, Nancy E.; Gibbs, James P.

    2011-01-01

    It has been postulated that road deicing salts are sufficiently diluted by spring rains to ameliorate any physiological impacts to amphibians breeding in wetlands near roads. We tested this conjecture by exposing clutches of the spotted salamander (Ambystoma maculatum) to three chloride concentrations (1 mg/L, 145 mg/L, 945 mg/L) for nine days, then transferred clutches to control water for nine days, and measured change in mass at three-day intervals. We measured mass change because water uptake by clutches reduces risks to embryos associated with freezing, predation, and disease. Clutches in controls sequestered water asymptotically. Those in the moderate concentrations lost 18% mass initially and regained 14% after transfer to control water. Clutches in high concentration lost 33% mass and then lost an additional 8% after transfer. Our results suggest that spring rains do not ameliorate the effects of deicing salts in wetlands with extremely high chloride concentrations. - Road deicing salts irreversibly disrupts osmoregulation of salamander egg clutches.

  9. Scaling Law for Irreversible Entropy Production in Critical Systems.

    Science.gov (United States)

    Hoang, Danh-Tai; Prasanna Venkatesh, B; Han, Seungju; Jo, Junghyo; Watanabe, Gentaro; Choi, Mahn-Soo

    2016-06-09

    We examine the Jarzynski equality for a quenching process across the critical point of second-order phase transitions, where absolute irreversibility and the effect of finite-sampling of the initial equilibrium distribution arise in a single setup with equal significance. We consider the Ising model as a prototypical example for spontaneous symmetry breaking and take into account the finite sampling issue by introducing a tolerance parameter. The initially ordered spins become disordered by quenching the ferromagnetic coupling constant. For a sudden quench, the deviation from the Jarzynski equality evaluated from the ideal ensemble average could, in principle, depend on the reduced coupling constant ε0 of the initial state and the system size L. We find that, instead of depending on ε0 and L separately, this deviation exhibits a scaling behavior through a universal combination of ε0 and L for a given tolerance parameter, inherited from the critical scaling laws of second-order phase transitions. A similar scaling law can be obtained for the finite-speed quench as well within the Kibble-Zurek mechanism.

  10. Irreversibility and higher-spin conformal field theory

    CERN Document Server

    Anselmi, D

    2000-01-01

    I discuss the idea that quantum irreversibility is a general principle of nature and a related "conformal hypothesis", stating that all fundamental quantum field theories should be renormalization-group (RG) interpolations between ultraviolet and infrared conformal fixed points. In particular, the Newton constant should be viewed as a low-energy effect of the RG scale. This approach leads naturally to consider higher-spin conformal field theories, which are here classified, as candidate high-energy theories. Bosonic conformal tensors have a positive-definite action, equal to the square of a field strength, and a higher-derivative gauge invariance. The central charges c and a are well defined and positive. I calculate their values and study the operator-product structure. Fermionic theories have no gauge invariance and can be coupled to Abelian and non-Abelian gauge fields in a renormalizable way. At the quantum level, they contribute to the one-loop beta function with the same sign as ordinary matter, admit a...

  11. The effects of irreversible electroporation (IRE on nerves.

    Directory of Open Access Journals (Sweden)

    Wei Li

    Full Text Available BACKGROUND: If a critical nerve is circumferentially involved with tumor, radical surgery intended to cure the cancer must sacrifice the nerve. Loss of critical nerves may lead to serious consequences. In spite of the impressive technical advancements in nerve reconstruction, complete recovery and normalization of nerve function is difficult to achieve. Though irreversible electroporation (IRE might be a promising choice to treat tumors near or involved critical nerve, the pathophysiology of the nerve after IRE treatment has not be clearly defined. METHODS: We applied IRE directly to a rat sciatic nerve to study the long term effects of IRE on the nerve. A sequence of 10 square pulses of 3800 V/cm, each 100 µs long was applied directly to rat sciatic nerves. In each animal of group I (IRE the procedure was applied to produce a treated length of about 10 mm. In each animal of group II (Control the electrodes were only applied directly on the sciatic nerve for the same time. Electrophysiological, histological, and functional studies were performed on immediately after and 3 days, 1 week, 3, 5, 7 and 10 weeks following surgery. FINDINGS: Electrophysiological, histological, and functional results show the nerve treated with IRE can attain full recovery after 7 weeks. CONCLUSION: This finding is indicative of the preservation of nerve involving malignant tumors with respect to the application of IRE pulses to ablate tumors completely. In summary, IRE may be a promising treatment tool for any tumor involving nerves.

  12. Irreversible chemical steps control intersubunit dynamics during translation

    Science.gov (United States)

    Marshall, R. Andrew; Dorywalska, Magdalena; Puglisi, Joseph D.

    2008-01-01

    The ribosome, a two-subunit macromolecular machine, deciphers the genetic code and catalyzes peptide bond formation. Dynamic rotational movement between ribosomal subunits is likely required for efficient and accurate protein synthesis, but direct observation of intersubunit dynamics has been obscured by the repetitive, multistep nature of translation. Here, we report a collection of single-molecule fluorescence resonance energy transfer assays that reveal a ribosomal intersubunit conformational cycle in real time during initiation and the first round of elongation. After subunit joining and delivery of correct aminoacyl-tRNA to the ribosome, peptide bond formation results in a rapid conformational change, consistent with the counterclockwise rotation of the 30S subunit with respect to the 50S subunit implied by prior structural and biochemical studies. Subsequent binding of elongation factor G and GTP hydrolysis results in a clockwise rotation of the 30S subunit relative to the 50S subunit, preparing the ribosome for the next round of tRNA selection and peptide bond formation. The ribosome thus harnesses the free energy of irreversible peptidyl transfer and GTP hydrolysis to surmount activation barriers to large-scale conformational changes during translation. Intersubunit rotation is likely a requirement for the concerted movement of tRNA and mRNA substrates during translocation. PMID:18824686

  13. General performance characteristics of an irreversible ferromagnetic Stirling refrigeration cycle

    International Nuclear Information System (INIS)

    Lin, G.; Tegus, O.; Zhang, L.; Brueck, E.

    2004-01-01

    A new magnetic-refrigeration-cycle model using ferromagnetic materials as a cyclic working substance is set up, in which finite-rate heat transfer, heat leak and regeneration time are taken into account. On the basis of the thermodynamic properties of a ferromagnetic material, the general performance characteristics of the ferromagnetic Stirling refrigeration cycle are investigated and the effects of some key irreversibilities on the performance of the cycle are revealed. By using the optimal-control theory, the optimal relation between the coefficient of performance and the cooling rate is derived and some important performance bounds, e.g., the maximum cooling rate, the maximum coefficient of performance, are determined. Moreover, the optimal operating regions for cooling rate, coefficient of performance and the optimal operating temperatures of a cyclic working substance in the two heat-transfer processes are obtained. Furthermore, the influences of magnetization and magnetic field on the performance characteristics of the cycle are discussed. The results obtained here have general significance and can be deduced to the related ones of the Stirling refrigeration cycle using paramagnetic salt as a cyclic working substance

  14. Ecological optimization and parametric study of irreversible Stirling and Ericsson heat pumps

    International Nuclear Information System (INIS)

    Tyagi, S.K.; Kaushik, S.C.; Salohtra, R.

    2002-01-01

    This communication presents the ecological optimization and parametric study of irreversible Stirling and Ericsson heat pump cycles, in which the external irreversibility is due to finite temperature difference between working fluid and external reservoirs while the internal irreversibilities are due to regenerative heat loss and other entropy generations within the cycle. The ecological function is defined as the heating load minus the irreversibility (power loss) which is ambient temperature times the entropy generation. The ecological function is optimized with respect to working fluid temperatures, and the expressions for various parameters at the optimal operating condition are obtained. The effects of different operating parameters on the performance of these cycles have been studied. It is found that the effect of internal irreversibility parameter is more pronounced than the other parameters on the performance of these cycles. (author)

  15. Macroscopic irreversibility and microscopic paradox: A Constructal law analysis of atoms as open systems

    Science.gov (United States)

    Lucia, Umberto

    2016-10-01

    The relation between macroscopic irreversibility and microscopic reversibility is a present unsolved problem. Constructal law is introduced to develop analytically the Einstein’s, Schrödinger’s, and Gibbs’ considerations on the interaction between particles and thermal radiation (photons). The result leads to consider the atoms and molecules as open systems in continuous interaction with flows of photons from their surroundings. The consequent result is that, in any atomic transition, the energy related to the microscopic irreversibility is negligible, while when a great number of atoms (of the order of Avogadro’s number) is considered, this energy related to irreversibility becomes so large that its order of magnitude must be taken into account. Consequently, macroscopic irreversibility results related to microscopic irreversibility by flows of photons and amount of atoms involved in the processes.

  16. Cell cycle checkpoints: reversible when possible, irreversible when needed

    NARCIS (Netherlands)

    Krenning, L.

    2015-01-01

    Cell cycle checkpoints are reversible in nature, and can prevent progression into the next cell cycle phase if needed. In the case of DNA damage, cells can prevent progression from G1 into S phase, and from G2 into mitosis in the presence of DNA double strand breaks. Following DNA repair, these

  17. A model of irreversible jam formation in dense traffic

    Science.gov (United States)

    Brankov, J. G.; Bunzarova, N. Zh.; Pesheva, N. C.; Priezzhev, V. B.

    2018-03-01

    We study an one-dimensional stochastic model of vehicular traffic on open segments of a single-lane road of finite size L. The vehicles obey a stochastic discrete-time dynamics which is a limiting case of the generalized Totally Asymmetric Simple Exclusion Process. This dynamics has been previously used by Bunzarova and Pesheva (2017) for an one-dimensional model of irreversible aggregation. The model was shown to have three stationary phases: a many-particle one, MP, a phase with completely filled configuration, CF, and a boundary perturbed MP+CF phase, depending on the values of the particle injection (α), ejection (β) and hopping (p) probabilities. Here we extend the results for the stationary properties of the MP+CF phase, by deriving exact expressions for the local density at the first site of the chain and the probability P(1) of a completely jammed configuration. The unusual phase transition, characterized by jumps in both the bulk density and the current (in the thermodynamic limit), as α crosses the boundary α = p from the MP to the CF phase, is explained by the finite-size behavior of P(1). By using a random walk theory, we find that, when α approaches from below the boundary α = p, three different regimes appear, as the size L → ∞: (i) the lifetime of the gap between the rightmost clusters is of the order O(L) in the MP phase; (ii) small jams, separated by gaps with lifetime O(1) , exist in the MP+CF phase close to the left chain boundary; and (iii) when β = p, the jams are divided by gaps with lifetime of the order O(L 1 / 2) . These results are supported by extensive Monte Carlo calculations.

  18. Programmes, resources, and needs of HIV-prevention nongovernmental organizations (NGOs) in Africa, Central/Eastern Europe and Central Asia, Latin America and the Caribbean.

    Science.gov (United States)

    Kelly, J A; Somlai, A M; Benotsch, E G; Amirkhanian, Y A; Fernandez, M I; Stevenson, L Y; Sitzler, C A; McAuliffe, T L; Brown, K D; Opgenorth, K M

    2006-01-01

    This study assessed the programmes, resources, and needs of HIV-prevention nongovernmental organizations (NGOs) in 75 countries in Africa, Central/Eastern Europe and Central Asia, Latin America and the Caribbean. Multiple databases and expert recommendations were used to identify one major HIV-prevention NGO in the capital or a large city in each country, and in-depth interviews were conducted with each NGO Director. Most NGOs are carrying out their programmes with minimal funding and few regularly employed personnel. Most are highly dependent on international donors, but reliance on small grants with short funding periods limits programme development capacity. HIV-prevention activities varied by region, with African NGOs most likely to use peer education and community awareness events; Eastern European NGOs most likely to offer needle exchange; Latin American NGOs to have resource centres and offer risk reduction programmes; and Caribbean organizations to use mass education approaches. Across regions, NGOs most often targeted the general public and youth, although specialized at-risk groups were the additional focus of attention in some regions. Limited funding, governmental indifference or opposition, AIDS stigma, and social discomfort discussing sex were often cited as barriers to new HIV-prevention programmes. NGOs are critical service providers. However, their funding, programmes, and resource capacities must be strengthened if NGOs are to realize their full potential in HIV prevention.

  19. Ictal time-irreversible intracranial EEG signals as markers of the epileptogenic zone.

    Science.gov (United States)

    Schindler, Kaspar; Rummel, Christian; Andrzejak, Ralph G; Goodfellow, Marc; Zubler, Frédéric; Abela, Eugenio; Wiest, Roland; Pollo, Claudio; Steimer, Andreas; Gast, Heidemarie

    2016-09-01

    To show that time-irreversible EEG signals recorded with intracranial electrodes during seizures can serve as markers of the epileptogenic zone. We use the recently developed method of mapping time series into directed horizontal graphs (dHVG). Each node of the dHVG represents a time point in the original intracranial EEG (iEEG) signal. Statistically significant differences between the distributions of the nodes' number of input and output connections are used to detect time-irreversible iEEG signals. In 31 of 32 seizure recordings we found time-irreversible iEEG signals. The maximally time-irreversible signals always occurred during seizures, with highest probability in the middle of the first seizure half. These signals spanned a large range of frequencies and amplitudes but were all characterized by saw-tooth like shaped components. Brain regions removed from patients who became post-surgically seizure-free generated significantly larger time-irreversibilities than regions removed from patients who still had seizures after surgery. Our results corroborate that ictal time-irreversible iEEG signals can indeed serve as markers of the epileptogenic zone and can be efficiently detected and quantified in a time-resolved manner by dHVG based methods. Ictal time-irreversible EEG signals can help to improve pre-surgical evaluation in patients suffering from pharmaco-resistant epilepsies. Copyright © 2016 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.

  20. Act No. 87-565 of 22 July 1987 on the organization of public safety measures, forestry protection against fires and the prevention of major risks

    International Nuclear Information System (INIS)

    1987-01-01

    As defined by this Act, the objective of the public safety measures is to prevent all types of major risks and to protect persons, property and the environment, including forests, against accidents, disasters and catastrophes. It deals with the conditions for preparing preventive measures and for implementing necessary measures in case of major risks or accidents. The preparation and organization of assistance are determined within the framework of ORSEC (ORganisation des SECours) plans and emergency plans; the first assess the possibilities for facing up to disasters while the latter provide for measures and means to overcome a particular risk [fr

  1. Pelvic floor muscle training for secondary prevention of pelvic organ prolapse (PREVPROL): a multicentre randomised controlled trial.

    Science.gov (United States)

    Hagen, Suzanne; Glazener, Cathryn; McClurg, Doreen; Macarthur, Christine; Elders, Andrew; Herbison, Peter; Wilson, Don; Toozs-Hobson, Philip; Hemming, Christine; Hay-Smith, Jean; Collins, Marissa; Dickson, Sylvia; Logan, Janet

    2017-01-28

    Pelvic floor muscle training can reduce prolapse severity and symptoms in women seeking treatment. We aimed to assess whether this intervention could also be effective in secondary prevention of prolapse and the need for future treatment. We did this multicentre, parallel-group, randomised controlled trial at three centres in New Zealand and the UK. Women from a longitudinal study of pelvic floor function after childbirth were potentially eligible for inclusion. Women of any age who had stage 1-3 prolapse, but had not sought treatment, were randomly assigned (1:1), via remote computer allocation, to receive either one-to-one pelvic floor muscle training (five physiotherapy appointments over 16 weeks, and annual review) plus Pilates-based pelvic floor muscle training classes and a DVD for home use (intervention group), or a prolapse lifestyle advice leaflet (control group). Randomisation was minimised by centre, parity (three or less vs more than three deliveries), prolapse stage (above the hymen vs at or beyond the hymen), and delivery method (any vaginal vs all caesarean sections). Women and intervention physiotherapists could not be masked to group allocation, but allocation was masked from data entry researchers and from the trial statistician until after database lock. The primary outcome was self-reported prolapse symptoms (Pelvic Organ Prolapse Symptom Score [POP-SS]) at 2 years. Analysis was by intention to treat. This trial is registered with ClinicalTrials.gov, number NCT01171846. Between Dec 21, 2008, and Feb 24, 2010, in New Zealand, and Oct 27, 2010, and Sept 5, 2011, in the UK, we randomly assigned 414 women to the intervention group (n=207) or the control group (n=207). One participant in each group was excluded after randomisation, leaving 412 women for analysis. At baseline, 399 (97%) women had prolapse above or at the level of the hymen. The mean POP-SS score at 2 years was 3·2 (SD 3·4) in the intervention group versus 4·2 (SD 4·4) in the

  2. Performance of an irreversible quantum Ericsson cooler at low temperature limit

    International Nuclear Information System (INIS)

    Wu Feng; Chen Lingen; Wu Shuang; Sun Fengrui

    2006-01-01

    The purpose of this paper is to investigate the effect of quantum properties of the working medium on the performance of an irreversible quantum Ericsson cooler with spin-1/2. The cooler is studied with the losses of heat resistance, heat leakage and internal irreversibility. The optimal relationship between the dimensionless cooling load R * versus the coefficient of performance ε for the irreversible quantum Ericsson cooler is derived. In particular, the performance characteristics of the cooler at the low temperature limit are discussed

  3. A Fingerprint Encryption Scheme Based on Irreversible Function and Secure Authentication

    Directory of Open Access Journals (Sweden)

    Yijun Yang

    2015-01-01

    Full Text Available A fingerprint encryption scheme based on irreversible function has been designed in this paper. Since the fingerprint template includes almost the entire information of users’ fingerprints, the personal authentication can be determined only by the fingerprint features. This paper proposes an irreversible transforming function (using the improved SHA1 algorithm to transform the original minutiae which are extracted from the thinned fingerprint image. Then, Chinese remainder theorem is used to obtain the biokey from the integration of the transformed minutiae and the private key. The result shows that the scheme has better performance on security and efficiency comparing with other irreversible function schemes.

  4. Optimization of the performance characteristics in an irreversible magnetic Brayton refrigeration cycle

    International Nuclear Information System (INIS)

    Wang Hao; Liu Sanqiu

    2008-01-01

    An irreversible cycle model of magnetic Brayton refrigerators is established, in which the thermal resistance and irreversibility in the two adiabatic processes are taken into account. Expressions for several important performance parameters, such as the coefficient of performance, cooling rate and power input are derived. Moreover, the optimal performance parameters are obtained at the maximum coefficient of performance. The optimization region (or criteria) for an irreversible magnetic Brayton refrigerator is obtained. The results obtained here have general significance and will be helpful to understand deeply the performance of a magnetic Brayton refrigeration cycle

  5. A fingerprint encryption scheme based on irreversible function and secure authentication.

    Science.gov (United States)

    Yang, Yijun; Yu, Jianping; Zhang, Peng; Wang, Shulan

    2015-01-01

    A fingerprint encryption scheme based on irreversible function has been designed in this paper. Since the fingerprint template includes almost the entire information of users' fingerprints, the personal authentication can be determined only by the fingerprint features. This paper proposes an irreversible transforming function (using the improved SHA1 algorithm) to transform the original minutiae which are extracted from the thinned fingerprint image. Then, Chinese remainder theorem is used to obtain the biokey from the integration of the transformed minutiae and the private key. The result shows that the scheme has better performance on security and efficiency comparing with other irreversible function schemes.

  6. Irreversible membrane fouling abatement through pre-deposited layer of hierarchical porous carbons

    KAUST Repository

    Hamad, Juma

    2014-11-01

    In this work, dual-templated hierarchical porous carbons (HPCs), produced from a coupled ice-hard templating approach, are shown to be a highly effective solution to the commonly occurring problem of irreversible fouling of low-pressure membranes used for pre-treatment in wastewater reuse. For the first time, dual-templated HPCs, along with their respective counterparts - single-templated meso-porous carbon (MPCs) (without macropores) - are tested in terms of their fouling reduction capacity and ability to remove different effluent organic matter fractions present in wastewater and compared with a commercially available powdered activated carbon (PAC). The synthesized HPCs provided exceptional fouling abatement, a 4-fold higher fouling reduction as compared to the previously reported best performing commercial PAC and ~2.5-fold better fouling reduction than their respective mesoporous counterpart. Thus, it is shown that not only mesoporosity, but macroporosity is also necessary to achieve high fouling reduction, thus emphasizing the need for dual templating. In the case of HPCs, the pre-deposition technique is also found to outperform the traditional sorbent-feed mixing approach, mainly in terms of removal of fouling components. Based on their superior performance, a high permeability (ultra-low-pressure) membrane consisting of the synthesized HPC pre-deposited on a large pore size membrane support (0.45μm membrane), is shown to give excellent pre-treatment performance for wastewater reuse application. © 2014 Elsevier Ltd.

  7. Enzymatic treatment for controlling irreversible membrane fouling in cross-flow humic acid-fed ultrafiltration

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Chien-Hwa [Department of Civil and Environment Engineering, Nanya Institute of Technology, Taoyuan, Taiwan (China); Fang, Lung-Chen; Lateef, Shaik Khaja [Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Taiwan (China); Wu, Chung-Hsin, E-mail: chunghsinwu@yahoo.com.tw [Department of Chemical and Materials Engineering, National Kaohsiung University of Applied Sciences, 415 Chien Kung Road, Kaohsiung 807, Taiwan (China); Lin, Cheng-Fang [Graduate Institute of Environmental Engineering, National Taiwan University, Taipei, Taiwan (China)

    2010-05-15

    Exploring reasonable ways to remove foulant is of great importance in order to allow sustainable operation of ultrafiltration (UF) membranes in water/wastewater treatment technology. Compounds of organic and inorganic origin largely contribute to irreversible fouling. This study attempted to remove problem of UF membrane fouling by using four different enzymes including {alpha}-amylase, lipase, cellulase and protease. This investigation showed that none of the above mentioned enzymes was found to be effective for the removal of foulant when used alone. However, when these enzymes were used in combination with NaOH and citric acid, about 90% cleaning was achieved. The addition of non-ionic surfactant to the enzymatic solution appears to increase the efficiency of flux recovery by reducing the adhesion of foulant species to the membrane surface through the decrease of contact angle. Field emission gun scanning electron microscopy, Fourier transform infrared spectroscopy and atomic force microscopy (AFM) techniques were employed to qualitatively illustrate the foulant characteristics. The surface roughness through AFM was used to explain the potential mechanism for the enzymatic cleaning.

  8. Irreversible catalyst activation enables hyperpolarization and water solubility for NMR signal amplification by reversible exchange.

    Science.gov (United States)

    Truong, Milton L; Shi, Fan; He, Ping; Yuan, Bingxin; Plunkett, Kyle N; Coffey, Aaron M; Shchepin, Roman V; Barskiy, Danila A; Kovtunov, Kirill V; Koptyug, Igor V; Waddell, Kevin W; Goodson, Boyd M; Chekmenev, Eduard Y

    2014-12-04

    Activation of a catalyst [IrCl(COD)(IMes)] (IMes = 1,3-bis(2,4,6-trimethylphenyl)imidazol-2-ylidene; COD = cyclooctadiene)] for signal amplification by reversible exchange (SABRE) was monitored by in situ hyperpolarized proton NMR at 9.4 T. During the catalyst-activation process, the COD moiety undergoes hydrogenation that leads to its complete removal from the Ir complex. A transient hydride intermediate of the catalyst is observed via its hyperpolarized signatures, which could not be detected using conventional nonhyperpolarized solution NMR. SABRE enhancement of the pyridine substrate can be fully rendered only after removal of the COD moiety; failure to properly activate the catalyst in the presence of sufficient substrate can lead to irreversible deactivation consistent with oligomerization of the catalyst molecules. Following catalyst activation, results from selective RF-saturation studies support the hypothesis that substrate polarization at high field arises from nuclear cross-relaxation with hyperpolarized (1)H spins of the hydride/orthohydrogen spin bath. Importantly, the chemical changes that accompanied the catalyst's full activation were also found to endow the catalyst with water solubility, here used to demonstrate SABRE hyperpolarization of nicotinamide in water without the need for any organic cosolvent--paving the way to various biomedical applications of SABRE hyperpolarization methods.

  9. The effect of small intestine heterogeneity on irreversible electroporation treatment planning.

    Science.gov (United States)

    Phillips, Mary

    2014-09-01

    Nonthermal irreversible electroporation (NTIRE) is an ablation modality that utilizes microsecond electric fields to produce nanoscale defects in the cell membrane. This results in selective cell death while preserving all other molecules, including the extracellular matrix. Here, finite element analysis and experimental results are utilized to examine the effect of NTIRE on the small intestine due to concern over collateral damage to this organ during NTIRE treatment of abdominal cancers. During previous studies, the electrical treatment parameters were chosen based on a simplified homogeneous tissue model. The small intestine, however, has very distinct layers, and a more realistic model is needed to further develop this technology for precise clinical applications. This study uses a two-dimensional finite element solution of the Laplace and heat conduction equations to investigate how small intestine heterogeneities affect the electric field and temperature distribution. Experimental results obtained by applying NTIRE to the rat small intestine in vivo support the heterogeneous effect of NTIRE on the tissue. The numerical modeling indicates that the electroporation parameters chosen for this study avoid thermal damage to the tissue. This is supported by histology obtained from the in vivo study, which showed preservation of extracellular structures. The finite element model also indicates that the heterogeneous structure of the small intestine has a significant effect on the electric field and volume of cell ablation during electroporation and could have a large impact on the extent of treatment. The heterogeneous nature of the tissue should be accounted for in clinical treatment planning.

  10. Preventive and social cost implications of Ebola Virus Disease (EVD) outbreak on selected organizations in Lagos state, Nigeria.

    Science.gov (United States)

    Olugasa, Babasola Oluseyi; Oshinowo, Oluwafunmilola Yemisi; Odigie, Eugene Amienwanlen

    2015-01-01

    As Ebola virus disease (EVD) continues to pose public health challenge in West Africa, with attending fears and socio-economic implications in the current epidemic challenges. It is compelling to estimate the social and preventive costs of EVD containment in a Nigerian city. Hence, this study was to determine the social and preventive cost implications of EVD among selected public institutions in Lagos, Nigeria, from July to December, 2014. Questionnaires and key-informants interview were administered to respondents and administrators of selected hospitals, hotels and schools in Eti-Osa Local Government Area of Lagos State. Knowledge of disease transmission, mortality and protocols for prevention, including cost of specific preventive measures adopted against EVD were elicited from respondents. Descriptive statistics and categorical analysis were used to summarize and estimate social and preventive costs incurred by respective institutions. An estimated five million, nineteen thousand, three hundred and seventy-nine Naira and eighty kobo (N5,019,379.80) only was observed as direct and social cost implication of EVD prevention. This amount translated into a conservative estimate of one billion, twenty-seven million, ninety-four thousand, seven hundred and fifty-six Naira (N1,027,094,756.10) for a total of four thousand schools, two hundred and fifty-three hospitals and one thousand, four hundred and fifty one hotels in Lagos during the period (July 20-November 20, 2014). The high cost of prevention of EVD within the short time-frame indicated high importance attached to a preventive policy against highly pathogenic zoonotic disease in Nigeria.

  11. Model for integrated management of quality, labor risks prevention, environment and ethical aspects, applied to R&D&I and production processes in an organization

    Science.gov (United States)

    González, M. R.; Torres, F.; Yoldi, V.; Arcega, F.; Plaza, I.

    2012-04-01

    It is proposed an integrated management model for an organization. This model is based on the continuous improvement Plan-Do-Check-Act cycle and it intends to integrate the environmental, risk prevention and ethical aspects as well as research, development and innovation projects management in the general quality management structure proposed by ISO 9001:2008. It aims to fulfill the standards ISO 9001, ISO 14001, OSHAS 18001, SGE 21 y 166002.

  12. Ecological optimization of an irreversible quantum Carnot heat engine with spin-1/2 systems

    International Nuclear Information System (INIS)

    Liu Xiaowei; Chen Lingen; Wu Feng; Sun Fengrui

    2010-01-01

    A model of a quantum heat engine with heat resistance, internal irreversibility and heat leakage and many non-interacting spin-1/2 systems is established in this paper. The quantum heat engine cycle is composed of two isothermal processes and two irreversible adiabatic processes and is referred to as a spin quantum Carnot heat engine. Based on the quantum master equation and the semi-group approach, equations of some important performance parameters, such as power output, efficiency, entropy generation rate and ecological function (a criterion representing the optimal compromise between exergy output rate and exergy loss rate), for the irreversible spin quantum Carnot heat engine are derived. The optimal ecological performance of the heat engine in the classical limit is analyzed with numerical examples. The effects of internal irreversibility and heat leakage on ecological performance are discussed in detail.

  13. Evaluation of properties of irreversible hydrocolloid impression materials mixed with disinfectant liquids

    Directory of Open Access Journals (Sweden)

    Arul Amalan

    2013-01-01

    Conclusion: Chlorhexidine solution can be used to mix irreversible hydrocolloid impression materials in regular dental practice as it did not significantly alter the properties. This may ensure effective disinfection of impressions.

  14. Treatise on irreversible and statistical thermodynamics an introduction to nonclassical thermodynamics

    CERN Document Server

    Yourgrau, Wolfgang; Raw, Gough

    2002-01-01

    Extensively revised edition of a much-respected work examines thermodynamics of irreversible processes, general principles of statistical thermodynamics, assemblies of noninteracting structureless particles, and statistical theory. 1966 edition.

  15. [Complex method of treating chronic, irreversible peripheral facial palsy particularly considering rehabilitation postoperatively].

    Science.gov (United States)

    Kukwa, A; Ignaczak, A; Pietniczka-Załeska, M; Matusiak, S

    1992-01-01

    Authors described the scheme of the functional reconstruction of the face in patients with protracted, irreversible, peripheral facial palsy and the subsequent rehabilitation. A new, own method of treatment has been introduced considering anatomical and functional relations.

  16. Sample size effect on the determination of the irreversibility line of high-Tc superconductors

    International Nuclear Information System (INIS)

    Li, Q.; Suenaga, M.; Li, Q.; Freltoft, T.

    1994-01-01

    The irreversibility lines of a high-J c superconducting Bi 2 Sr 2 Ca 2 Cu 3 O x /Ag tape were systematically measured upon a sequence of subdivisions of the sample. The irreversibility field H r (T) (parallel to the c axis) was found to change approximately as L 0.13 , where L is the effective dimension of the superconducting tape. Furthermore, it was found that the irreversibility line for a grain-aligned Bi 2 Sr 2 Ca 2 Cu 3 O x specimen can be approximately reproduced by the extrapolation of this relation down to a grain size of a few tens of micrometers. The observed size effect could significantly obscure the real physical meaning of the irreversibility lines. In addition, this finding surprisingly indicated that the Bi 2 Sr 2 Ca 2 Cu 2 O x /Ag tape and grain-aligned specimen may have similar flux line pinning strength

  17. Irreversibility analysis for gravity driven non-Newtonian liquid film along an inclined isothermal plate

    International Nuclear Information System (INIS)

    Makinde, O.D.

    2005-10-01

    In this paper, the first and second law of thermodynamics are employed in order to study the inherent irreversibility for a gravity driven non-Newtonian Ostwald-de Waele power law liquid film along an inclined isothermal plate. Based on some simplified assumptions, the governing equations are obtained and solved analytically. Expressions for fluid velocity, temperature, volumetric entropy generation numbers, irreversibility distribution ratio and the Bejan number are also determined. (author)

  18. Performance Optimization of Generalized Irreversible Refrigerator Based on a New Ecological Criterion

    OpenAIRE

    Xu, Jie; Pang, Liping; Wang, Jun

    2013-01-01

    On the basis of the exergy analysis, a performance optimization is carried out for a generalized irreversible refrigerator model, which takes into account the heat resistance, heat leakage and internal irreversibility losses. A new ecological criterion, named coefficient of performance of exergy (COPE), defined as the dimensionless ratio of the exergy output rate to the exergy loss rate, is proposed as an objective function in this paper. The optimal performance factors which maximize the eco...

  19. Irreversible Electroporation of a Hepatocellular Carcinoma Lesion Adjacent to a Transjugular Intrahepatic Portosystemic Shunt Stent Graft

    Energy Technology Data Exchange (ETDEWEB)

    Niessen, Christoph; Jung, Ernst Michael; Wohlgemuth, Walter A. [Department of Radiology, University Medical Center Regensburg, Regensburg D-93053 (Germany); Trabold, Benedikt [Department of Anaesthesia, University Medical Center Regensburg, Regensburg D-93053 (Germany); Haimerl, Michael; Schreyer, Andreas; Stroszczynski, Christian; Wiggermann, Philipp [Department of Radiology, University Medical Center Regensburg, Regensburg D-93053 (Germany)

    2013-07-01

    We report in a 65-year-old man hepatocellular carcinoma adjacent to a transjugular intrahepatic portosystemic shunt stent-graft which was successfully treated with irreversible electroporation (IRE). IRE is a new non-thermal tissue ablation technique which uses electrical pulses to induce cell necrosis by irreversible membrane poration. IRE proved to be more advantageous in the ablation of perivascular tumor with little injury to the surrounding structures.

  20. Process boundaries of irreversible scCO2 -assisted phase separation in biphasic whole-cell biocatalysis.

    Science.gov (United States)

    Brandenbusch, Christoph; Glonke, Sebastian; Collins, Jonathan; Hoffrogge, Raimund; Grunwald, Klaudia; Bühler, Bruno; Schmid, Andreas; Sadowski, Gabriele

    2015-11-01

    The formation of stable emulsions in biphasic biotransformations catalyzed by microbial cells turned out to be a major hurdle for industrial implementation. Recently, a cost-effective and efficient downstream processing approach, using supercritical carbon dioxide (scCO2 ) for both irreversible emulsion destabilization (enabling complete phase separation within minutes of emulsion treatment) and product purification via extraction has been proposed by Brandenbusch et al. (2010). One of the key factors for a further development and scale-up of the approach is the understanding of the mechanism underlying scCO2 -assisted phase separation. A systematic approach was applied within this work to investigate the various factors influencing phase separation during scCO2 treatment (that is pressure, exposure of the cells to CO2 , and changes of cell surface properties). It was shown that cell toxification and cell disrupture are not responsible for emulsion destabilization. Proteins from the aqueous phase partially adsorb to cells present at the aqueous-organic interface, causing hydrophobic cell surface characteristics, and thus contribute to emulsion stabilization. By investigating the change in cell-surface hydrophobicity of these cells during CO2 treatment, it was found that a combination of catastrophic phase inversion and desorption of proteins from the cell surface is responsible for irreversible scCO2 mediated phase separation. These findings are essential for the definition of process windows for scCO2 -assisted phase separation in biphasic whole-cell biocatalysis. © 2015 Wiley Periodicals, Inc.

  1. Study of the irreversible trapping of dihydrogen with the use of a MnO2/Ag2O mixture

    International Nuclear Information System (INIS)

    Galliez, K.

    2012-01-01

    The hydrogen risk generated by radiolysis of organic compounds during a nuclear waste transport is a major issue. The use of irreversible getters is considered to limit this risk. The aim of this work is to study one of these getters, MnO 2 /Ag 2 O, in order to better understand the trapping phenomenon and to ensure its reliability. Initially several parameters affecting the trapping kinetics were studied. It has been shown that among all MnO 2 allotropic phases, the nsutite has the best trapping kinetics. Moreover, specific surface area and defect amount in MnO 2 can enhance trapping performances. Ag 2 O weight percentage (acting as promotor) has been determined at 13% to have the best trapping kinetics. Chemisorption of H 2 , which is required for its application, has been shown by using several characterization techniques such as magnetometry, infrared spectroscopy and electronic energy loss spectroscopy. The trapping irreversibility and the regeneration of the getter have been demonstrated respectively under nitrogen or air at 150 C. Finally, proton insertion mechanism in MnO 2 has been elucidated by pairs distribution function analysis through the development of a model to simulate the complex structure of MnO 2 . It has been shown that Ag 2 O is turned into Ag 2 CO 3 during the preparation of the getter under water, which has never been demonstrated. (author) [fr

  2. Core indicators evaluation of effectiveness of HIV-AIDS preventive-control programmes carried out by nongovernmental organizations. A mixed method study

    Directory of Open Access Journals (Sweden)

    Mansilla Rosa

    2011-07-01

    Full Text Available Abstract Background The number of nongovernmental organizations working on AIDS has grown. There is great diversity in the type of activities and population groups that have been targeted. The purposes of this study are: to describe and analyze the objectives and HIV-AIDS preventive activities that are carried out by the AIDS-NGOs that work with AIDS in Catalonia and that receive subsidies from the Department of Health; and to develop a comprehensive proposal for measurable and agreed upon core quality evaluation indicators to monitor and assess those objectives and activities that can have an impact on the fight against inequalities and stigmatization, and incorporate the perspectives of the service providers and users. Methods A mixed method study has been carried out with professionals from the 36 NGOs that work with HIV/AIDS in Catalonia, as well as their users. This study achieved the completeness model using the following phases: 1. A systematic review of AIDS-NGOs annual reports and preparation of a catalogue of activities grouped by objectives, level of prevention and AIDS-NGOs target population; 2. A transversal study through an ad-hoc questionnaire administered to the AIDS-NGOs representatives; 3. A qualitative study with a phenomenological approach through focus groups, individual interviews and observations; 4. Consensus meetings between AIDS-NGOs professionals and the research team using Haddon matrices in order to establish a proposal of evaluation indicators. Results The information was classified according to level of prevention and level of intervention. A total of 248 objectives and 258 prevention activities were identified. 1564 evaluation indicators, addressed to 7 target population groups, were produced. Thirty core activities were selected. The evaluation indicators proposed for these activities were: 76 indicators for 15 primary prevention activities, 43 for 5 secondary prevention activities and 68 for 10 tertiary

  3. Characterization of irreversible physio-mechanical processes in stretched fetal membranes.

    Science.gov (United States)

    Marom, Yulia; Goldman, Shlomit; Shalev, Eliezer; Shilo, Doron

    2016-01-01

    We perform bulge tests on live fetal membrane (FM) tissues that simulate the mechanical conditions prior to contractions. Experimental results reveal an irreversible mechanical behavior that appears during loading and is significantly different than the mechanical behavior that appears during unloading or in subsequent loading cycles. The irreversible behavior results in a residual strain that does not recover upon unloading and remains the same for at least 1h after the FM is unloaded. Surprisingly, the irreversible behavior demonstrates a linear stress-strain relation. We introduce a new model for the mechanical response of collagen tissues, which accounts for the irreversible deformation and provides predictions in agreement with our experimental results. The basic assumption of the model is that the constitutive stress-strain relationship of individual elements that compose the collagen fibers has a plateau segment during which an irreversible transformation/deformation occurs. Fittings of calculated and measured stress-strain curves reveal a well-defined single-value property of collagenous tissues, which is related to the threshold strain εth for irreversible transformation. Further discussion of several physio-mechanical processes that can induce irreversible behavior indicate that the most probable process, which is in agreement with our results for εth, is a phase transformation of collagen molecules from an α-helix to a β-sheet structure. A phase transformation is a manifestation of a significant change in the molecular structure of the collagen tissues that can alter connections with surrounding molecules and may lead to critical biological changes, e.g., an initiation of labor. This study is driven by the hypothesis that pre-contraction mechanical stretch of the fetal membrane (FM) can lead to a change in the microstructure of the FM, which in turn induces a critical biological (hormonal) change that leads to the initiation of labor. We present

  4. Synthesis, structural characterization, docking, lipophilicity and cytotoxicity of 1-[(1R)-1-(6-fluoro-1,3-benzothiazol-2-yl)ethyl]-3-alkyl carbamates, novel acetylcholinesterase and butyrylcholinesterase pseudo-irreversible inhibitors

    Czech Academy of Sciences Publication Activity Database

    Pejchal, V.; Štěpánková, Š.; Pejchalová, M.; Královec, K.; Havelek, R.; Růžičková, Z.; Ajani, Haresh; Lo, Rabindranath; Lepšík, Martin

    2016-01-01

    Roč. 24, č. 7 (2016), s. 1560-1572 ISSN 0968-0896 R&D Projects: GA ČR GBP208/12/G016 Institutional support: RVO:61388963 Keywords : halogenated benzothiazole * carbamates * acetylcholinesterase * butyrylcholinesterase inhibition * pseudo-irreversible mechanism * covalent docking Subject RIV: CC - Organic Chemistry Impact factor: 2.930, year: 2016

  5. Short- and Mid-term Effects of Irreversible Electroporation on Normal Renal Tissue: An Animal Model

    Energy Technology Data Exchange (ETDEWEB)

    Wendler, J. J., E-mail: johann.wendler@med.ovgu.de; Porsch, M.; Huehne, S.; Baumunk, D. [University of Magdeburg, Department of Urology (Germany); Buhtz, P. [Institute of Pathology, University of Magdeburg (Germany); Fischbach, F.; Pech, M. [University of Magdeburg, Department of Radiology (Germany); Mahnkopf, D. [Institute of Medical Technology and Research (Germany); Kropf, S. [Institute of Biometry, University of Magdeburg (Germany); Roessner, A. [Institute of Pathology, University of Magdeburg (Germany); Ricke, J. [University of Magdeburg, Department of Radiology (Germany); Schostak, M.; Liehr, U.-B. [University of Magdeburg, Department of Urology (Germany)

    2013-04-15

    Irreversible electroporation (IRE) is a novel nonthermal tissue ablation technique by high current application leading to apoptosis without affecting extracellular matrix. Previous results of renal IRE shall be supplemented by functional MRI and differentiated histological analysis of renal parenchyma in a chronic treatment setting. Three swine were treated with two to three multifocal percutaneous IRE of the right kidney. MRI was performed before, 30 min (immediate-term), 7 days (short-term), and 28 days (mid-term) after IRE. A statistical analysis of the lesion surrounded renal parenchyma intensities was made to analyze functional differences depending on renal part, side and posttreatment time. Histological follow-up of cortex and medulla was performed after 28 days. A total of eight ablations were created. MRI showed no collateral damage of surrounded tissue. The highest visual contrast between lesions and normal parenchyma was obtained by T2-HR-SPIR-TSE-w sequence of DCE-MRI. Ablation zones showed inhomogeneous necroses with small perifocal edema in the short-term and sharp delimitable scars in the mid-term. MRI showed no significant differences between adjoined renal parenchyma around ablations and parenchyma of untreated kidney. Histological analysis demonstrated complete destruction of cortical glomeruli and tubules, while collecting ducts, renal calyxes, and pelvis of medulla were preserved. Adjoined kidney parenchyma around IRE lesions showed no qualitative differences to normal parenchyma of untreated kidney. This porcine IRE study reveals a multifocal renal ablation, while protecting surrounded renal parenchyma and collecting system over a mid-term period. That offers prevention of renal function ablating centrally located or multifocal renal masses.

  6. The origin of bore-core remanences: mechanical-shock-imposed irreversible magnetizations

    Science.gov (United States)

    Shi, H.; Tarling, D. H.

    1999-06-01

    Repeated laboratory-induced weak mechanical shocking (c. 0.57 kg m s^- ^1 ) of marine sandstone samples showing drilling-induced remanence, from commercial bore cores from the North Sea and Prudhoe Bay, causes increases in their low-field susceptibility (chi) and their ability to acquire an isothermal remanent magnetization (IRM). These enhancements are reduced by some 20 per cent by AF demagnetization in 100 mT. Doubling the intensity of the shock doubles the susceptibilities and IRMs acquired. The susceptibility increase ceases after 300 to 400 shocks for the North Sea samples and 20 to 30 shocks for those from Prudhoe Bay, while the IRM saturates after 800-1000 and 30-50 shocks respectively. Continental, haematite-bearing sandstones from commercial bore cores with no drilling-induced remanence subjected to the same shocks do not show these effects. Differences in the magnetic mineralogy of shocked and unshocked marine samples suggest that the magnetic enhancement is predominantly due to the creation of pyrrhotite by shock-induced irreversible crystallographic changes in iron-bearing sulphides. When shocked during commercial drilling, these new ferromagnetic minerals acquire strong chemical (crystalline) remanences, associated with a wide spectrum of grain sizes, in the magnetic field of the drill string, and these are resistant to both thermal and AF demagnetization. Similar processes are likely in any situation involving the shock of physically metastable iron-bearing minerals, particularly anoxic sediments. A 5 cm non-magnetic collar between the drill stem and crown should drastically reduce the magnetic intensity of this effect under commercial conditions, but would not prevent its occurrence.

  7. Short- and Mid-term Effects of Irreversible Electroporation on Normal Renal Tissue: An Animal Model

    International Nuclear Information System (INIS)

    Wendler, J. J.; Porsch, M.; Hühne, S.; Baumunk, D.; Buhtz, P.; Fischbach, F.; Pech, M.; Mahnkopf, D.; Kropf, S.; Roessner, A.; Ricke, J.; Schostak, M.; Liehr, U.-B.

    2013-01-01

    Irreversible electroporation (IRE) is a novel nonthermal tissue ablation technique by high current application leading to apoptosis without affecting extracellular matrix. Previous results of renal IRE shall be supplemented by functional MRI and differentiated histological analysis of renal parenchyma in a chronic treatment setting. Three swine were treated with two to three multifocal percutaneous IRE of the right kidney. MRI was performed before, 30 min (immediate-term), 7 days (short-term), and 28 days (mid-term) after IRE. A statistical analysis of the lesion surrounded renal parenchyma intensities was made to analyze functional differences depending on renal part, side and posttreatment time. Histological follow-up of cortex and medulla was performed after 28 days. A total of eight ablations were created. MRI showed no collateral damage of surrounded tissue. The highest visual contrast between lesions and normal parenchyma was obtained by T2-HR-SPIR-TSE-w sequence of DCE-MRI. Ablation zones showed inhomogeneous necroses with small perifocal edema in the short-term and sharp delimitable scars in the mid-term. MRI showed no significant differences between adjoined renal parenchyma around ablations and parenchyma of untreated kidney. Histological analysis demonstrated complete destruction of cortical glomeruli and tubules, while collecting ducts, renal calyxes, and pelvis of medulla were preserved. Adjoined kidney parenchyma around IRE lesions showed no qualitative differences to normal parenchyma of untreated kidney. This porcine IRE study reveals a multifocal renal ablation, while protecting surrounded renal parenchyma and collecting system over a mid-term period. That offers prevention of renal function ablating centrally located or multifocal renal masses.

  8. Palmitoylation of caveolin-1 in endothelial cells is post-translational but irreversible

    Science.gov (United States)

    Parat, M. O.; Fox, P. L.

    2001-01-01

    Caveolin-1 is a palmitoylated protein involved in assembly of signaling molecules in plasma membrane subdomains termed caveolae and in intracellular cholesterol transport. Three cysteine residues in the C terminus of caveolin-1 are subject to palmitoylation, which is not necessary for caveolar targeting of caveolin-1. Protein palmitoylation is a post-translational and reversible modification that may be regulated and that in turn may regulate conformation, membrane association, protein-protein interactions, and intracellular localization of the target protein. We have undertaken a detailed analysis of [(3)H]palmitate incorporation into caveolin-1 in aortic endothelial cells. The linkage of palmitate to caveolin-1 was hydroxylamine-sensitive and thus presumably a thioester bond. However, contrary to expectations, palmitate incorporation was blocked completely by the protein synthesis inhibitors cycloheximide and puromycin. In parallel experiments to show specificity, palmitoylation of aortic endothelial cell-specific nitric-oxide synthase was unaffected by these reagents. Inhibitors of protein trafficking, brefeldin A and monensin, blocked caveolin-1 palmitoylation, indicating that the modification was not cotranslational but rather required caveolin-1 transport from the endoplasmic reticulum and Golgi to the plasma membrane. In addition, immunophilin chaperones that form complexes with caveolin-1, i.e. FK506-binding protein 52, cyclophilin A, and cyclophilin 40, were not necessary for caveolin-1 palmitoylation because agents that bind immunophilins did not inhibit palmitoylation. Pulse-chase experiments showed that caveolin-1 palmitoylation is essentially irreversible because the release of [(3)H]palmitate was not significant even after 24 h. These results show that [(3)H]palmitate incorporation is limited to newly synthesized caveolin-1, not because incorporation only occurs during synthesis but because the continuous presence of palmitate on caveolin-1 prevents

  9. Involving immigrant religious organizations in HIV/AIDS prevention: The role of bonding and bridging social capital.

    Science.gov (United States)

    Leung, ManChui R; Chin, John J; Petrescu-Prahova, Miruna

    2016-08-01

    Immigrant religious organizations in the United States are uniquely positioned to address critical issues beyond religion because of their moral, social and cultural prominence in community life. Increasingly, religious organizations have taken on a leadership role around health issues such as decreasing HIV/AIDS stigma and misinformation. However, there are barriers for some religious leaders and organizations in adopting new health programs, especially if the issue is seen as controversial. Our study examines how social network structures among religious members influence organizational acceptance of new information or controversial ideas, like HIV/AIDS. Using social network analysis methods on data from 2841 contacts in 20 immigrant Chinese Buddhist temples and Christian churches in New York City, we tested whether an immigrant religious organization's likelihood of being involved in HIV/AIDS activities was associated with the presence of bonding or bridging social capital. These two forms of social capital have been found to mediate the levels of exposure and openness to new ideas. We found HIV/AIDS-involved religious organizations were more likely to have lower levels of bonding social capital as indicated by members having fewer ties and fewer demographic attributes in common. We also found HIV/AIDS-involved religious organizations were more likely to have higher levels of bridging social capital as indicated by members having significantly more ties to people outside of their organization. Our study highlights the importance of looking beyond religion type and leadership attributes to social network structures among members in order to better explain organization-level receptiveness to HIV/AIDS involvement. Copyright © 2016 Elsevier Ltd. All rights reserved.

  10. Non-input analysis for incomplete trapping irreversible tracer with PET.

    Science.gov (United States)

    Ohya, Tomoyuki; Kikuchi, Tatsuya; Fukumura, Toshimitsu; Zhang, Ming-Rong; Irie, Toshiaki

    2013-07-01

    When using metabolic trapping type tracers, the tracers are not always trapped in the target tissue; i.e., some are completely trapped in the target, but others can be eliminated from the target tissue at a measurable rate. The tracers that can be eliminated are termed 'incomplete trapping irreversible tracers'. These incomplete trapping irreversible tracers may be clinically useful when the tracer β-value, the ratio of the tracer (metabolite) elimination rate to the tracer efflux rate, is under approximately 0.1. In this study, we propose a non-input analysis for incomplete trapping irreversible tracers based on the shape analysis (Shape), a non-input analysis used for irreversible tracers. A Monte Carlo simulation study based on experimental monkey data with two actual PET tracers (a complete trapping irreversible tracer [(11)C]MP4A and an incomplete trapping irreversible tracer [(18)F]FEP-4MA) was performed to examine the effects of the environmental error and the tracer elimination rate on the estimation of the k3-parameter (corresponds to metabolic rate) using Shape (original) and modified Shape (M-Shape) analysis. The simulation results were also compared with the experimental results obtained with the two PET tracers. When the tracer β-value was over 0.03, the M-Shape method was superior to the Shape method for the estimation of the k3-parameter. The simulation results were also in reasonable agreement with the experimental ones. M-Shape can be used as the non-input analysis of incomplete trapping irreversible tracers for PET study. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. Fluctuation theorems in feedback-controlled open quantum systems: Quantum coherence and absolute irreversibility

    Science.gov (United States)

    Murashita, Yûto; Gong, Zongping; Ashida, Yuto; Ueda, Masahito

    2017-10-01

    The thermodynamics of quantum coherence has attracted growing attention recently, where the thermodynamic advantage of quantum superposition is characterized in terms of quantum thermodynamics. We investigate the thermodynamic effects of quantum coherent driving in the context of the fluctuation theorem. We adopt a quantum-trajectory approach to investigate open quantum systems under feedback control. In these systems, the measurement backaction in the forward process plays a key role, and therefore the corresponding time-reversed quantum measurement and postselection must be considered in the backward process, in sharp contrast to the classical case. The state reduction associated with quantum measurement, in general, creates a zero-probability region in the space of quantum trajectories of the forward process, which causes singularly strong irreversibility with divergent entropy production (i.e., absolute irreversibility) and hence makes the ordinary fluctuation theorem break down. In the classical case, the error-free measurement ordinarily leads to absolute irreversibility, because the measurement restricts classical paths to the region compatible with the measurement outcome. In contrast, in open quantum systems, absolute irreversibility is suppressed even in the presence of the projective measurement due to those quantum rare events that go through the classically forbidden region with the aid of quantum coherent driving. This suppression of absolute irreversibility exemplifies the thermodynamic advantage of quantum coherent driving. Absolute irreversibility is shown to emerge in the absence of coherent driving after the measurement, especially in systems under time-delayed feedback control. We show that absolute irreversibility is mitigated by increasing the duration of quantum coherent driving or decreasing the delay time of feedback control.

  12. The use of TiO2 nanoparticles to reduce refrigerator ir-reversibility

    International Nuclear Information System (INIS)

    Padmanabhan, Venkataramana Murthy V.; Palanisamy, Senthilkumar

    2012-01-01

    Highlights: ► COP of hydrocarbons mixture VCRSs increases less when compared to R134a. ► Compressor ir-reversibility of VCRSs decreases by 33% (R134a), 14% (R436A and R436B). ► Total ir-reversibility of selected VCRSs decreases. ► Exergy efficiency of R134a is exceptionally low at lower reference temperature. ► Exergy efficiency of selected VCRSs increases. - Abstract: The ir-reversibility at the process of a vapour-compression refrigeration system (VCRS) with nanoparticles in the working fluid was investigated experimentally. Mineral oil (MO) with 0.1 g L −1 TiO 2 nanoparticles mixture were used as the lubricant instead of Polyol-ester (POE) oil in the R134a, R436A (R290/R600a-56/44-wt.%) and R436B (R290/R600a-52/48-wt.%)VCRSs. The VCRS ir-reversibility at the process with the nanoparticles was investigated using second law of thermodynamics. The results indicate that R134a, R436A and R436B and MO with TiO 2 nanoparticles work normally and safely in the VCRS. The VCRSs total ir-reversibility (529, 588 and 570 W) at different process was better than the R134a, R436A and R436B and POE oil system (777, 697 and 683 W). The same tests with Al 2 O 3 nanoparticles showed that the different nanoparticles properties have little effect on the VCRS ir-reversibility. Thus, TiO 2 nanoparticles can be used in VCRS with reciprocating compressor to considerably reduce ir-reversibility at the process.

  13. Patient-, organization-, and system-level barriers and facilitators to preventive oral health care: a convergent mixed-methods study in primary dental care.

    Science.gov (United States)

    Templeton, Anna Rose; Young, Linda; Bish, Alison; Gnich, Wendy; Cassie, Heather; Treweek, Shaun; Bonetti, Debbie; Stirling, Douglas; Macpherson, Lorna; McCann, Sharon; Clarkson, Jan; Ramsay, Craig

    2016-01-12

    Dental caries is the most common chronic disease of adult and childhood, a largely preventable yet widespread, costly public health problem. This study identified patient-, organization-, and system-level factors influencing routine delivery of recommended care for prevention and management of caries in primary dental care. A convergent mixed-methods design assessed six guidance-recommended behaviours to prevent and manage caries (recording risk, risk-based recall intervals, applying fluoride varnish, placing preventive fissure sealants, demonstrating oral health maintenance, taking dental x-rays). A diagnostic questionnaire assessing current practice, beliefs, and practice characteristics was sent to a random sample of 651 dentists in National Health Service (NHS) Scotland. Eight in-depth case studies comprising observation of routine dental visits and dental team member interviews were conducted. Patient feedback was collected from adult patients with recent checkups at case study practices. Key informant interviews were conducted with decision makers in policy, funding, education, and regulation. The Theoretical Domains Framework within the Behaviour Change Wheel was used to identify and describe patient-, organization-, and system-level barriers and facilitators to care. Findings were merged into a matrix describing theoretical domains salient to each behaviour. The matrix and Behaviour Change Wheel were used to prioritize behaviours for change and plan relevant intervention strategies. Theoretical domains associated with best practice were identified from the questionnaire (N-196), case studies (N = 8 practices, 29 interviews), and patient feedback (N = 19). Using the study matrix, key stakeholders identified priority behaviours (use of preventive fissure sealants among 6-12-year-olds) and strategies (audit and feedback, patient informational campaign) to improve guidance implementation. Proposed strategies were assessed as appropriate for immediate

  14. Comparing ELISA test-positive prevalence, risk factors and management recommendations for Johne's disease prevention between organic and conventional dairy farms in Ontario, Canada.

    Science.gov (United States)

    Pieper, Laura; Sorge, Ulrike S; DeVries, Trevor; Godkin, Ann; Lissemore, Kerry; Kelton, David

    2015-11-01

    Johne's disease (JD) is a chronic, infectious disease in cattle. Between 2010 and 2013, a voluntary JD control program was successfully launched in Ontario, Canada, including a Risk Assessment and Management Plan (RAMP) and JD ELISA testing of the entire milking herd. Over the last decade, the organic dairy sector has been growing. However, organic farming regulations and philosophies may influence the risk for JD transmission on Ontario organic dairy farms. The aim of this cross-sectional study was to investigate differences in JD ELISA test positive prevalence, risk factors for JD and recommendations for JD prevention between organic and conventional dairy herds in Ontario. RAMP results (i.e. RAMP scores and recommendations) and ELISA results were available for 2103 dairy herds, including 42 organic herds. If available, additional data on milk production, milk quality, and herd characteristics were gathered. Organic and conventional herds had a similar herd-level JD ELISA test-positive prevalence (26.2% and 27.2%, respectively). Organic herds (4.2%) had a higher within-herd JD ELISA test-positive prevalence compared to conventional herds (2.3%) if they had at least one JD test-positive animal on the farm. Organic farms had lower risk scores for biosecurity (9 points lower), and higher scores in the calving (7 points higher) and the calf-rearing management areas (4 points higher). After accounting for RAMP score, organic farms received fewer recommendations for the calving management area (Odds Ratio=0.41) and more recommendations in the adult cow management area (Odds Ratio=2.70). A zero-inflated negative binomial model was built with purchase of animals and the herd size included in the logistic portion of the model. Herd type (organic or conventional), colostrum and milk feeding practices, average bulk tank somatic cell count, and presence of non-Holstein breeds were included in the negative binomial portion of the model. Organic farms had a higher number of

  15. Critical appraisal on the use of everolimus in renal transplantation as an immunosuppressant to prevent organ transplant rejection

    Directory of Open Access Journals (Sweden)

    Fernando Giron

    2010-01-01

    Full Text Available Fernando Giron, Yenny BaezKidney Transplant Service, Colombiana de Trasplantes, Bogota, ColombiaAbstract: Everolimus is a proliferation inhibitor designed to target chronic allograft nephropathy including prevention of acute rejection. Acute renal allograft rejection incidence varies with the therapy used for immunosuppression. Registry data show that 15% to 35% of kidney recipients will undergo treatment for at least one episode of acute rejection within the first post-transplant year. Everolimus has been used as therapy with full- or reduced-dose cyclosporine A without evidence of increasing the acute rejection incidence. This review will summarize the available clinical trial data on the use of everolimus and its role in preventing acute rejection incidence in renal transplantation.Keywords: calcineurin inhibitors, cyclosporine, everolimus, biopsy-proven acute rejection, renal transplantation, acute rejection

  16. Health Technology Assessment of CEM Pulpotomy in Permanent Molars with Irreversible Pulpitis.

    Science.gov (United States)

    Yazdani, Shahram; Jadidfard, Mohammad-Pooyan; Tahani, Bahareh; Kazemian, Ali; Dianat, Omid; Alim Marvasti, Laleh

    2014-01-01

    Teeth with irreversible pulpitis usually undergo root canal therapy (RCT). This treatment modality is often considered disadvantageous as it removes vital pulp tissue and weakens the tooth structure. A relatively new concept has risen which suggests vital pulp therapy (VPT) for irreversible pulpitis. VPT with calcium enriched mixture (VPT/CEM) has demonstrated favorable treatment outcomes when treating permanent molars with irreversible pulpitis. This study aims to compare patient related factors, safety and organizational consideration as parts of health technology assessment (HTA) of the new VPT/CEM biotechnology when compared with RCT. Patient related factors were assessed by looking at short- and long-term clinical success; safety related factors were evaluated by a specialist committee and discussion board involved in formulating healthcare policies. Organizational evaluation was performed and the social implications were assessed by estimating the costs, availability, accessibility and acceptability. The impact of VPT/CEM biotechnology was assessed by investigating the incidence of irreversible pulpitis and the effect of this treatment on reducing the burden of disease. VPT/CEM biotechnology was deemed feasible and acceptable like RCT; however, it was more successful, accessible, affordable, available and also safer than RCT. When considering socioeconomic implications on oral health status and oral health-related quality of life of VPT/CEM, the novel biotechnology can be more effective and more efficient than RCT in mature permanent molars with irreversible pulpitis.

  17. Health Technology Assessment of CEM Pulpotomy in Permanent Molars with Irreversible Pulpitis

    Science.gov (United States)

    Yazdani, Shahram; Jadidfard, Mohammad-Pooyan; Tahani, Bahareh; Kazemian, Ali; Dianat, Omid; Alim Marvasti, Laleh

    2014-01-01

    Introduction: Teeth with irreversible pulpitis usually undergo root canal therapy (RCT). This treatment modality is often considered disadvantageous as it removes vital pulp tissue and weakens the tooth structure. A relatively new concept has risen which suggests vital pulp therapy (VPT) for irreversible pulpitis. VPT with calcium enriched mixture (VPT/CEM) has demonstrated favorable treatment outcomes when treating permanent molars with irreversible pulpitis. This study aims to compare patient related factors, safety and organizational consideration as parts of health technology assessment (HTA) of the new VPT/CEM biotechnology when compared with RCT. Materials and Methods: Patient related factors were assessed by looking at short- and long-term clinical success; safety related factors were evaluated by a specialist committee and discussion board involved in formulating healthcare policies. Organizational evaluation was performed and the social implications were assessed by estimating the costs, availability, accessibility and acceptability. The impact of VPT/CEM biotechnology was assessed by investigating the incidence of irreversible pulpitis and the effect of this treatment on reducing the burden of disease. Results: VPT/CEM biotechnology was deemed feasible and acceptable like RCT; however, it was more successful, accessible, affordable, available and also safer than RCT. Conclusion: When considering socioeconomic implications on oral health status and oral health-related quality of life of VPT/CEM, the novel biotechnology can be more effective and more efficient than RCT in mature permanent molars with irreversible pulpitis. PMID:24396372

  18. Substance P and CGRP expression in dental pulps with irreversible pulpitis.

    Science.gov (United States)

    Sattari, Mandana; Mozayeni, Mohammad Ali; Matloob, Arash; Mozayeni, Maryam; Javaheri, Homan H

    2010-08-01

    The purpose of this study was to compare substance P (SP) and calcitonin gene-related peptide (CGRP) expression in pulp tissue with clinically diagnosed symptomatic and asymptomatic irreversible pulpitis. Healthy pulps acted as controls. Five normal pulps and 40 with irreversible pulpitis (20 symptomatic and 20 asymptomatic) were obtained from 45 different patients. SP and CGRP expression was determined by competition binding assays using enzyme immunoassay. anova and Mann-Whitney tests were used to ascertain if there were statistically significant differences between the groups. The results showed that neuropeptides were found in all pulp samples. The highest and the lowest expressions for SP and CGRP were found in symptomatic irreversible pulpitis and healthy pulps groups, respectively. The differences between healthy pulps and the groups of pulps having irreversible pulpitis were significant (P pulpitis groups (P pulpitis groups were not significant. This study demonstrated that the expression of CGRP and SP is significantly higher in pulps with irreversible pulpitis compared with healthy pulps.

  19. Organizing and conducting career guidance and crime prevention among young people by means of physical culture and sports specialized university departments Internal Affairs of Ukraine.

    Directory of Open Access Journals (Sweden)

    Zakorko I.P

    2011-06-01

    Full Text Available At the present stage of social development takes on special urgency the problem of finding new means and methods of crime prevention among youth in the context of strengthening the nation's health. In our opinion, employees of the Ukrainian Interior Ministry must take a decisive role in solving these problems. One of the most effective ways to solve them is to organize youth sports schools and clubs to professionally-applied sports at the bases of relevant departments of higher educational institutions of Ministry of Internal Affairs of Ukraine, the involvement of the best specialists and trainers.

  20. Intragenomic conflict in populations infected by Parthenogenesis Inducing Wolbachia ends with irreversible loss of sexual reproduction.

    Science.gov (United States)

    Stouthamer, Richard; Russell, James E; Vavre, Fabrice; Nunney, Leonard

    2010-07-28

    The maternally inherited, bacterial symbiont, parthenogenesis inducing (PI) Wolbachia, causes females in some haplodiploid insects to produce daughters from both fertilized and unfertilized eggs. The symbionts, with their maternal inheritance, benefit from inducing the production of exclusively daughters, however the optimal sex ratio for the nuclear genome is more male-biased. Here we examine through models how an infection with PI-Wolbachia in a previously uninfected population leads to a genomic conflict between PI-Wolbachia and the nuclear genome. In most natural populations infected with PI-Wolbachia the infection has gone to fixation and sexual reproduction is impossible, specifically because the females have lost their ability to fertilize eggs, even when mated with functional males. The PI Wolbachia infection by itself does not interfere with the fertilization process in infected eggs, fertilized infected eggs develop into biparental infected females. Because of the increasingly female-biased sex ratio in the population during a spreading PI-Wolbachia infection, sex allocation alleles in the host that cause the production of more sons are rapidly selected. In haplodiploid species a reduced fertilization rate leads to the production of more sons. Selection for the reduced fertilization rate leads to a spread of these alleles through both the infected and uninfected population, eventually resulting in the population becoming fixed for both the PI-Wolbachia infection and the reduced fertilization rate. Fertilization rate alleles that completely interfere with fertilization ("virginity alleles") will be selected over alleles that still allow for some fertilization. This drives the final resolution of the conflict: the irreversible loss of sexual reproduction and the complete dependence of the host on its symbiont. This study shows that dependence among organisms can evolve rapidly due to the resolution of the conflicts between cytoplasmic and nuclear genes, and

  1. Intragenomic conflict in populations infected by Parthenogenesis Inducing Wolbachia ends with irreversible loss of sexual reproduction

    Science.gov (United States)

    2010-01-01

    Background The maternally inherited, bacterial symbiont, parthenogenesis inducing (PI) Wolbachia, causes females in some haplodiploid insects to produce daughters from both fertilized and unfertilized eggs. The symbionts, with their maternal inheritance, benefit from inducing the production of exclusively daughters, however the optimal sex ratio for the nuclear genome is more male-biased. Here we examine through models how an infection with PI-Wolbachia in a previously uninfected population leads to a genomic conflict between PI-Wolbachia and the nuclear genome. In most natural populations infected with PI-Wolbachia the infection has gone to fixation and sexual reproduction is impossible, specifically because the females have lost their ability to fertilize eggs, even when mated with functional males. Results The PI Wolbachia infection by itself does not interfere with the fertilization process in infected eggs, fertilized infected eggs develop into biparental infected females. Because of the increasingly female-biased sex ratio in the population during a spreading PI-Wolbachia infection, sex allocation alleles in the host that cause the production of more sons are rapidly selected. In haplodiploid species a reduced fertilization rate leads to the production of more sons. Selection for the reduced fertilization rate leads to a spread of these alleles through both the infected and uninfected population, eventually resulting in the population becoming fixed for both the PI-Wolbachia infection and the reduced fertilization rate. Fertilization rate alleles that completely interfere with fertilization ("virginity alleles") will be selected over alleles that still allow for some fertilization. This drives the final resolution of the conflict: the irreversible loss of sexual reproduction and the complete dependence of the host on its symbiont. Conclusions This study shows that dependence among organisms can evolve rapidly due to the resolution of the conflicts between

  2. An experimental and numerical investigation of phase change electrodes for therapeutic irreversible electroporation.

    Science.gov (United States)

    Arena, Christopher B; Mahajan, Roop L; Nichole Rylander, Marissa; Davalos, Rafael V

    2013-11-01

    Irreversible electroporation (IRE) is a new technology for ablating aberrant tissue that utilizes pulsed electric fields (PEFs) to kill cells by destabilizing their plasma membrane. When treatments are planned correctly, the pulse parameters and location of the electrodes for delivering the pulses are selected to permit destruction of the target tissue without causing thermal damage to the surrounding structures. This allows for the treatment of surgically inoperable masses that are located near major blood vessels and nerves. In select cases of high-dose IRE, where a large ablation volume is desired without increasing the number of electrode insertions, it can become challenging to design a pulse protocol that is inherently nonthermal. To solve this problem we have developed a new electrosurgical device that requires no external equipment or protocol modifications. The design incorporates a phase change material (PCM) into the electrode core that melts during treatment and absorbs heat out of the surrounding tissue. Here, this idea is reduced to practice by testing hollow electrodes filled with gallium on tissue phantoms and monitoring temperature in real time. Additionally, the experimental data generated are used to validate a numerical model of the heat transfer problem, which is then applied to investigate the cooling performance of other classes of PCMs. The results indicate that metallic PCMs, such as gallium, are better suited than organics or salt hydrates for thermal management, because their comparatively higher thermal conductivity aids in heat dissipation. However, the melting point of the metallic PCM must be properly adjusted to ensure that the phase transition is not completed before the end of treatment. When translated clinically, phase change electrodes have the potential to continue to allow IRE to be performed safely near critical structures, even in high-dose cases.

  3. Spatial and Functional Organization of Pig Trade in Different European Production Systems: Implications for Disease Prevention and Control.

    Science.gov (United States)

    Relun, Anne; Grosbois, Vladimir; Sánchez-Vizcaíno, José Manuel; Alexandrov, Tsviatko; Feliziani, Francesco; Waret-Szkuta, Agnès; Molia, Sophie; Etter, Eric Marcel Charles; Martínez-López, Beatriz

    2016-01-01

    Understanding the complexity of live pig trade organization is a key factor to predict and control major infectious diseases, such as classical swine fever (CSF) or African swine fever (ASF). Whereas the organization of pig trade has been described in several European countries with indoor commercial production systems, little information is available on this organization in other systems, such as outdoor or small-scale systems. The objective of this study was to describe and compare the spatial and functional organization of live pig trade in different European countries and different production systems. Data on premise characteristics and pig movements between premises were collected during 2011 from Bulgaria, France, Italy, and Spain, which swine industry is representative of most of the production systems in Europe (i.e., commercial vs. small-scale and outdoor vs. indoor). Trade communities were identified in each country using the Walktrap algorithm. Several descriptive and network metrics were generated at country and community levels. Pig trade organization showed heterogeneous spatial and functional organization. Trade communities mostly composed of indoor commercial premises were identified in western France, northern Italy, northern Spain, and north-western Bulgaria. They covered large distances, overlapped in space, demonstrated both scale-free and small-world properties, with a role of trade operators and multipliers as key premises. Trade communities involving outdoor commercial premises were identified in western Spain, south-western and central France. They were more spatially clustered, demonstrated scale-free properties, with multipliers as key premises. Small-scale communities involved the majority of premises in Bulgaria and in central and Southern Italy. They were spatially clustered and had scale-free properties, with key premises usually being commercial production premises. These results indicate that a disease might spread very differently

  4. Performance Optimization of Generalized Irreversible Refrigerator Based on a New Ecological Criterion

    Directory of Open Access Journals (Sweden)

    Jie Xu

    2013-11-01

    Full Text Available On the basis of the exergy analysis, a performance optimization is carried out for a generalized irreversible refrigerator model, which takes into account the heat resistance, heat leakage and internal irreversibility losses. A new ecological criterion, named coefficient of performance of exergy (COPE, defined as the dimensionless ratio of the exergy output rate to the exergy loss rate, is proposed as an objective function in this paper. The optimal performance factors which maximize the ecological objective function have been discussed. Numerical examples are given to explain the influences of heat leakage and internal irreversibility on the generalized and optimal performances. This new ecological criterion may be beneficial for determining the reasonable design of refrigerators.

  5. Effect of regeneration on the thermo-ecological performance analysis and optimization of irreversible air refrigerators

    Science.gov (United States)

    Ust, Yasin

    2010-04-01

    A thermo-ecological performance analysis of an irreversible regenerative air refrigerator cycle exchanging heat with thermal reservoirs is presented. In the analysis, the external irreversibility effects due to heat transfer across finite temperature differences and the heat leak loss between the external heat reservoirs while the internal irreversibilities are due to the non-isentropic compression and expansion processes and the regenerative loss are taken into account. The effects of regeneration and heat sources temperature ratio are given special emphasis and investigated in detail. A comparative performance analysis considering the objective functions of an ecological coefficient of performance, exergetic efficiency and coefficient of performance is also carried out. The maximum of the objective functions and the corresponding optimal conditions have been derived analytically. The obtained results may provide a general theoretical tool for the thermo-ecological design of regenerative air refrigerators.

  6. Statistical Irreversible Thermodynamics in the Framework of Zubarev's Nonequilibrium Statistical Operator Method

    Science.gov (United States)

    Luzzi, R.; Vasconcellos, A. R.; Ramos, J. G.; Rodrigues, C. G.

    2018-01-01

    We describe the formalism of statistical irreversible thermodynamics constructed based on Zubarev's nonequilibrium statistical operator (NSO) method, which is a powerful and universal tool for investigating the most varied physical phenomena. We present brief overviews of the statistical ensemble formalism and statistical irreversible thermodynamics. The first can be constructed either based on a heuristic approach or in the framework of information theory in the Jeffreys-Jaynes scheme of scientific inference; Zubarev and his school used both approaches in formulating the NSO method. We describe the main characteristics of statistical irreversible thermodynamics and discuss some particular considerations of several authors. We briefly describe how Rosenfeld, Bohr, and Prigogine proposed to derive a thermodynamic uncertainty principle.

  7. Long buccal nerve block injection pain in patients with irreversible pulpitis.

    Science.gov (United States)

    Drum, Melissa; Reader, Al; Beck, Mike

    2011-07-01

    The purpose of this study was to determine the pain associated with needle insertion (with or without topical anesthetic) and solution deposition for the long buccal nerve block injection in patients with irreversible pulpitis. Initial pain and any differences by age and gender were also studied. One hundred twelve emergency patients with irreversible pulpitis received long buccal nerve block injections using 2% lidocaine with 1:100,000 epinephrine. The patients recorded pain of needle insertion and solution deposition on a Heft-Parker visual analog scale (VAS). Moderate-to-severe pain occurred from 41% to 46% of the time with the long buccal nerve block. The use of topical anesthetic did not statistically decrease the pain of needle insertion. In conclusion, 41% to 46% of patients presenting with irreversible pulpitis have the potential for moderate-to-severe pain with the long buccal nerve block. Copyright © 2011 Mosby, Inc. All rights reserved.

  8. FINITE TIME THERMODYNAMIC MODELING AND ANALYSIS FOR AN IRREVERSIBLE ATKINSON CYCLE

    Directory of Open Access Journals (Sweden)

    Yanlin Ge

    2010-01-01

    Full Text Available Performance of an air-standard Atkinson cycle is analyzed by using finite-time thermodynamics. The irreversible cycle model which is more close to practice is founded. In this model, the non-linear relation between the specific heats of working fluid and its temperature, the friction loss computed according to the mean velocity of the piston, the internal irreversibility described by using the compression and expansion efficiencies, and heat transfer loss are considered. The relations between the power output and the compression ratio, between the thermal efficiency and the compression ratio, as well as the optimal relation between power output and the efficiency of the cycle are derived by detailed numerical examples. Moreover, the effects of internal irreversibility, heat transfer loss and friction loss on the cycle performance are analyzed. The results obtained in this paper may provide guidelines for the design of practical internal combustion engines.

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

    Directory of Open Access Journals (Sweden)

    Kazuyuki Takata

    2017-10-01

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

  10. [The survival and development conditions of community-based organizations for HIV/AIDS prevention and control among men who have sex with men in three Chinese cities].

    Science.gov (United States)

    Fu, Xiaojing; Shan, Duo; Qi, Jinlei; Ouyang, Lin; Wang, Hui; Fu, Jie; Sun, Jiangping

    2015-06-01

    To investigate the survival and development conditions of community-based organizations (CBOs) for HIV/AIDS prevention and control among men who have sex with men (MSM) in Chinese cities including Shanghai, Hangzhou, Chongqing. This study employed both qualitative (focus groups) and quantitative (questionnaire survey) methods to obtain information from 15 MSM CBOs in three Chinese cities. The mean work time of the 15 CBOs for HIV/AIDS prevention and control among MSM was 6.7 years (2.1-11.3 years), and the majority of their funds was from international cooperation projects (80 447 000 RMB, 73.0%) from 2006 to 2013. The survival cost of MSM CBOs apart from expenditure of activities was 2 240-435 360 RMB per year. As it was shown in the graph, the survival and development of MSM CBOs was closely related to the development of international cooperation projects. There was a few small size MSM CBOs taking part in the prevention and control of HIV/AIDS and their work content was limited before 2006. From 2006 to 2008, some international cooperation projects were launched in China, such as the China Global Fund AIDS project and the China-Gates Foundation HIV Prevention Cooperation program. As a result, the number of MSM CBOs was increased sharply, and both the scale and 2012, the performance of these programs further promote the establishment of new MSM CBOs and the development of all MSM CBOs with regard to the work places, full-time staffs, work contents, work patterns and the specific targeted population. After 2012, most international cooperation programs were completed and the local department of disease prevention and control continued to cooperate with MSM CBOs. However, the degree of support funds from the local department was different among different regions. Where the funds were below the half of program funds, the development of MSM CBOs ceased and work slowed down. Besides, there were still some constraints for the survival and development of MSM CBOs, such

  11. Reducing Cancer Health Disparities through Community Engagement: Working with Faith-Based Organizations (Project CHURCH) | Division of Cancer Prevention

    Science.gov (United States)

    Speaker | "Reducing Cancer Health Disparities through Community Engagement: Working with Faith-Based Organizations (Project CHURCH)" will be presented by Lorna H. McNeill, PhD, MPH, Chair of the Department of Health Disparities at the University of Texas MD Anderson Cancer Center in Houston, TX. Date: 2/20/2018; Time: 11:00am - 12:00pm; Location: NCI Shady Grove Campus, Conference Room Seminar 110 Terrace Level East.

  12. Canonical formalism, fundamental equation, and generalized thermomechanics for irreversible fluids with heat transfer

    International Nuclear Information System (INIS)

    Sieniutycz, S.; Berry, R.S.

    1993-01-01

    A Lagrangian with dissipative (e.g., Onsager's) potentials is constructed for the field description of irreversible heat-conducting fluids, off local equilibrium. Extremum conditions of action yield Clebsch representations of temperature, chemical potential, velocities, and generalized momenta, including a thermal momentum introduced recently [R. L. Selinger and F. R. S. Whitham, Proc. R. Soc. London, Ser. A 302, 1 (1968); S. Sieniutycz and R. S. Berry, Phys. Rev. A 40, 348 (1989)]. The basic question asked is ''To what extent may irreversibility, represented by a given form of the entropy source, influence the analytical form of the conservation laws for the energy and momentum?'' Noether's energy for a fluid with heat flow is obtained, which leads to a fundamental equation and extended Hamiltonian dynamics obeying the second law of thermodynamics. While in the case of the Onsager potentials this energy coincides numerically with the classical energy E, it contains an extra term (vanishing along the path) still contributing to an irreversible evolution. Components of the energy-momentum tensor preserve all terms regarded standardly as ''irreversible'' (heat, tangential stresses, etc.) generalized to the case when thermodynamics includes the state gradients and the so-called thermal phase, which we introduce here. This variable, the Lagrange multiplier of the entropy generation balance, is crucial for consistent treatment of irreversible processes via an action formalism. We conclude with the hypothesis that embedding the first and second laws in the context of the extremal behavior of action under irreversible conditions may imply accretion of an additional term to the classical energy

  13. Inequalities for trace anomalies, length of the RG flow, distance between the fixed points and irreversibility

    International Nuclear Information System (INIS)

    Anselmi, Damiano

    2004-01-01

    I discuss several issues about the irreversibility of the RG flow and the trace anomalies c, a and a'. First I argue that in quantum field theory: (i) the scheme-invariant area Δ a' of the graph of the effective beta function between the fixed points defines the length of the RG flow; (ii) the minimum of Δ a' in the space of flows connecting the same UV and IR fixed points defines the (oriented) distance between the fixed points and (iii) in even dimensions, the distance between the fixed points is equal to Δ a = a UV - a IR . In even dimensions, these statements imply the inequalities 0 ≤ Δ a ≤ Δ a' and therefore the irreversibility of the RG flow. Another consequence is the inequality a ≤ c for free scalars and fermions (but not vectors), which can be checked explicitly. Secondly, I elaborate a more general axiomatic set-up where irreversibility is defined as the statement that there exist no pairs of non-trivial flows connecting interchanged UV and IR fixed points. The axioms, based on the notions of length of the flow, oriented distance between the fixed points and certain 'oriented-triangle inequalities', imply the irreversibility of the RG flow without a global a function. I conjecture that the RG flow is also irreversible in odd dimensions (without a global a function). In support of this, I check the axioms of irreversibility in a class of d = 3 theories where the RG flow is integrable at each order of the large N expansion

  14. Antibacterial efficacy and effect of chlorhexidine mixed with irreversible hydrocolloid for dental impressions: a randomized controlled trial.

    Science.gov (United States)

    Cubas, Glória; Valentini, Fernanda; Camacho, Guilherme Brião; Leite, Fábio; Cenci, Maximiliano Sérgio; Pereira-Cenci, Tatiana

    2014-01-01

    This study aimed to evaluate whether chlorhexidine mixed with irreversible hydrocolloid powder decreases microbial contamination during impression taking without affecting the resulting casts. Twenty volunteers were randomly divided into two groups (n = 10) according to the liquid used for impression taking in conjunction with irreversible hydrocolloid: 0.12% chlorhexidine or water. Surface roughness and dimensional stability of the casts were evaluated. Chlorhexidine mixed with irreversible hydrocolloid decreased the percentage of microorganisms when compared with water (P impression quality.

  15. A Research Strategy Case Study of Alcohol and Drug Prevention by Non-Governmental Organizations in Sweden 2003-2009

    Directory of Open Access Journals (Sweden)

    Larsson Madelene

    2011-04-01

    Full Text Available Abstract Background Alcohol and drug prevention is high on the public health agenda in many countries. An increasing trend is the call for evidence-based practice. In Sweden in 2002 an innovative project portfolio including an integrated research and competence-building strategy for non-governmental organisations (NGOs was designed by the National Board of Health and Welfare (NBHW. This research strategy case study is based on this initiative. Methods The embedded case study includes 135 projects in 69 organisations and 14 in-depth process or effect studies. The data in the case study has been compiled using multiple methods - administrative data; interviews and questionnaires to project leaders; focus group discussions and seminars; direct and participatory observations, interviews, and documentation of implementation; consultations with the NBHW and the NGOs; and a literature review. Annual reports have been submitted each year and three bi-national conferences Reflections on preventions have been held. Results A broad range of organisations have been included in the NBHW project portfolio. A minority of the project were run by Alcohol or drug organisations, while a majority has children or adolescents as target groups. In order to develop a trustful partnership between practitioners, national agencies and researchers a series of measures were developed and implemented: meeting with project leaders, project dialogues and consultations, competence strengthening, support to documentation, in-depth studies and national conferences. A common element was that the projects were program-driven and not research-driven interventions. The role of researchers-as-technical advisors was suitable for the fostering of a trustful partnership for research and development. The independence of the NGOs was regarded as important for the momentum in the project implementation. The research strategy also includes elements of participatory research. Conclusions This

  16. A Research Strategy Case Study of Alcohol and Drug Prevention by Non-Governmental Organizations in Sweden 2003-2009

    Science.gov (United States)

    2011-01-01

    Background Alcohol and drug prevention is high on the public health agenda in many countries. An increasing trend is the call for evidence-based practice. In Sweden in 2002 an innovative project portfolio including an integrated research and competence-building strategy for non-governmental organisations (NGOs) was designed by the National Board of Health and Welfare (NBHW). This research strategy case study is based on this initiative. Methods The embedded case study includes 135 projects in 69 organisations and 14 in-depth process or effect studies. The data in the case study has been compiled using multiple methods - administrative data; interviews and questionnaires to project leaders; focus group discussions and seminars; direct and participatory observations, interviews, and documentation of implementation; consultations with the NBHW and the NGOs; and a literature review. Annual reports have been submitted each year and three bi-national conferences Reflections on preventions have been held. Results A broad range of organisations have been included in the NBHW project portfolio. A minority of the project were run by Alcohol or drug organisations, while a majority has children or adolescents as target groups. In order to develop a trustful partnership between practitioners, national agencies and researchers a series of measures were developed and implemented: meeting with project leaders, project dialogues and consultations, competence strengthening, support to documentation, in-depth studies and national conferences. A common element was that the projects were program-driven and not research-driven interventions. The role of researchers-as-technical advisors was suitable for the fostering of a trustful partnership for research and development. The independence of the NGOs was regarded as important for the momentum in the project implementation. The research strategy also includes elements of participatory research. Conclusions This research strategy case

  17. The universal power and efficiency characteristics for irreversible reciprocating heat engine cycles

    CERN Document Server

    Qin Xiao Yong; Sun Feng Rui; Wu Chih

    2003-01-01

    The performance of irreversible reciprocating heat engine cycles with heat transfer loss and friction-like term loss is analysed using finite-time thermodynamics. The universal relations between the power output and the compression ratio, between the thermal efficiency and the compression ratio, and the optimal relation between power output and the efficiency of the cycles are derived. Moreover, analysis and optimization of the model were carried out in order to investigate the effect of cycle processes on the performance of the cycle using numerical examples. The results obtained herein include the performance characteristics of irreversible reciprocating Diesel, Otto, Atkinson and Brayton cycles.

  18. Effects of irreversibility and economics on the performance of a heat engine

    International Nuclear Information System (INIS)

    Ibrahim, O.M.; Klein, S.A.; Mitchell, J.W.

    1992-01-01

    In this paper, optimization of the power output of an internally irreversible heat engine is considered for finite capacitance rates of the external fluid streams. The method of Lagrange multipliers is used to solve for working fluid temperatures which yield maximum power. Analytical expressions for the maximum power and the cycle efficiency at miximum power are obtained. The effects of irreversibility and economics on the performance of a heat engine are investigated. A relationship between the maximum power point and economically optimum design is identified. It is demonstrated that, with certain reasonable economic assumptions, the maximum power point of a heat engine corresponds to a point of minimum life-cycle costs

  19. Irreversible Change of the Pore Structure of ZIF-8 in Carbon Dioxide Capture with Water Coexistence

    DEFF Research Database (Denmark)

    Liu, Huang; Guo, Ping; Regueira Muñiz, Teresa

    2016-01-01

    showed an irreversible change of its framework, which occurs during the CO2 capture process. It was found that there is an irreversible chemical reaction among ZIF-8, water, and CO2, which creates both zinc carbonate (or zinc carbonate hydroxides) and single 2-methylimidazole crystals, and therefore...... the pore structure of ZIF-8 collapses. It is suggested therefore that care must be taken when using ZIF-8 or products containing ZIF-8 for gas capture, gas separation, or other applications where both water and acid gases coexist....

  20. Irreversible magnetization process and switching mechanism in L10 FePt thin films

    Directory of Open Access Journals (Sweden)

    A. Lisfi

    2017-05-01

    Full Text Available The irreversible characteristics of the magnetization and the switching mechanism have been investigated in granular FePt films with L10 phase prepared by sputtering on a polymer substrate. The films display an extremely large magnetic anisotropy with a random distribution of the magnetization easy axis. The magnetic instabilities and the irreversible magnetization are found to be controlled by domain wall, which is responsible for the magnetization reversal. Through remanence curves and ΔM plot, the nature of magnetic interactions was revealed to be positive exchange coupling.

  1. Antibacterial efficacy and effect of Morinda citrifolia L. mixed with irreversible hydrocolloid for dental impressions: A randomized controlled trial.

    Science.gov (United States)

    Ahmed, A Shafath; Charles, P David; Cholan, R; Russia, M; Surya, R; Jailance, L

    2015-08-01

    This study aimed to evaluate whether the extract of Morinda citrifolia L. mixed with irreversible hydrocolloid powder decreases microbial contamination during impression making without affecting the resulting casts. Twenty volunteers were randomly divided into two groups (n = 10). Group A 30 ml extract of M. citrifolia L diluted in 30 ml of water was mixed to make the impression with irreversible hydrocolloid material. Group B 30 ml deionized water was mixed with irreversible hydrocolloid material to make the impressions following which the surface roughness and dimensional stability of casts were evaluated. Extract of M. citrifolia L. mixed with irreversible hydrocolloid decreased the percentage of microorganisms when compared with water (P impression quality.

  2. Spatial and functional organization of pig trade in different european production systems: implications for disease prevention and control

    Directory of Open Access Journals (Sweden)

    Anne eRelun

    2016-02-01

    Full Text Available Understanding the complexity of live pig trade organization is a key factor to predict and control major infectious diseases such as Classical or African swine fever. Whereas the organization of pig trade has been described in several European countries with indoor commercial production systems, little information is available on this organisation in other systems like outdoor or small-scale systems. The objective of this study was to describe and compare the spatial and functional organisation of live pig trade in different European countries and different production systems. Data on premise characteristics and pig movements between premises were collected during 2011 from Bulgaria, France, Italy and Spain, which swine industry is representative of most of the production systems in Europe (i.e. commercial vs small-scale; outdoor vs indoor. Trade communities were identified in each country using the Walktrap algorithm. Several descriptive and network metrics were generated at country and community level. Pig trade organization showed heterogeneous spatial and functional organization. Trade communities mostly composed of indoor commercial premises were identified in Western France, Northern Italy, Northern Spain and North-Western Bulgaria. They covered large distances, overlapped in space, demonstrated both scale-free and small-world properties, with a role of trade operators and multipliers as key premises. Trade communities involving outdoor commercial premises were identified in Western Spain, South-Western and Central France. They were more spatially clustered, demonstrated scale-free properties, with multipliers as key premises. Small-scale communities involved the majority of premises in Bulgaria and in central and Southern Italy. They were spatially clustered and had scale-free properties, with key premises usually being commercial production premises. These results indicate that a disease might spread very differently according to the

  3. Macromolecular Design Strategies for Preventing Active-Material Crossover in Non-Aqueous All-Organic Redox-Flow Batteries.

    Science.gov (United States)

    Doris, Sean E; Ward, Ashleigh L; Baskin, Artem; Frischmann, Peter D; Gavvalapalli, Nagarjuna; Chénard, Etienne; Sevov, Christo S; Prendergast, David; Moore, Jeffrey S; Helms, Brett A

    2017-02-01

    Intermittent energy sources, including solar and wind, require scalable, low-cost, multi-hour energy storage solutions in order to be effectively incorporated into the grid. All-Organic non-aqueous redox-flow batteries offer a solution, but suffer from rapid capacity fade and low Coulombic efficiency due to the high permeability of redox-active species across the battery's membrane. Here we show that active-species crossover is arrested by scaling the membrane's pore size to molecular dimensions and in turn increasing the size of the active material above the membrane's pore-size exclusion limit. When oligomeric redox-active organics (RAOs) were paired with microporous polymer membranes, the rate of active-material crossover was reduced more than 9000-fold compared to traditional separators at minimal cost to ionic conductivity. This corresponds to an absolute rate of RAO crossover of less than 3 μmol cm -2  day -1 (for a 1.0 m concentration gradient), which exceeds performance targets recently set forth by the battery industry. This strategy was generalizable to both high and low-potential RAOs in a variety of non-aqueous electrolytes, highlighting the versatility of macromolecular design in implementing next-generation redox-flow batteries. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Tolerogenic interactions between CD8+ dendritic cells and NKT cells prevent rejection of bone marrow and organ grafts.

    Science.gov (United States)

    Hongo, David; Tang, Xiaobin; Zhang, Xiangyue; Engleman, Edgar G; Strober, Samuel

    2017-03-23

    The combination of total lymphoid irradiation and anti-T-cell antibodies safely induces immune tolerance to combined hematopoietic cell and organ allografts in humans. Our mouse model required host natural killer T (NKT) cells to induce tolerance. Because NKT cells normally depend on signals from CD8 + dendritic cells (DCs) for their activation, we used the mouse model to test the hypothesis that, after lymphoid irradiation, host CD8 + DCs play a requisite role in tolerance induction through interactions with NKT cells. Selective deficiency of either CD8 + DCs or NKT cells abrogated chimerism and organ graft acceptance. After radiation, the CD8 + DCs increased expression of surface molecules required for NKT and apoptotic cell interactions and developed suppressive immune functions, including production of indoleamine 2,3-deoxygenase. Injection of naive mice with apoptotic spleen cells generated by irradiation led to DC changes similar to those induced by lymphoid radiation, suggesting that apoptotic body ingestion by CD8 + DCs initiates tolerance induction. Tolerogenic CD8 + DCs induced the development of tolerogenic NKT cells with a marked T helper 2 cell bias that, in turn, regulated the differentiation of the DCs and suppressed rejection of the transplants. Thus, reciprocal interactions between CD8 + DCs and invariant NKT cells are required for tolerance induction in this system that was translated into a successful clinical protocol. © 2017 by The American Society of Hematology.

  5. Irreversible impacts of heat on the emissions of monoterpenes, sesquiterpenes, phenolic BVOC and green leaf volatiles from several tree species

    Directory of Open Access Journals (Sweden)

    E. Kleist

    2012-12-01

    Full Text Available Climate change will induce extended heat waves to parts of the vegetation more frequently. High temperatures may act as stress (thermal stress on plants changing emissions of biogenic volatile organic compounds (BVOCs. As BVOCs impact the atmospheric oxidation cycle and aerosol formation, it is important to explore possible alterations of BVOC emissions under high temperature conditions. Applying heat to European beech, Palestine oak, Scots pine, and Norway spruce in a laboratory setup either caused the well-known exponential increases of BVOC emissions or induced irreversible changes of BVOC emissions. Considering only irreversible changes of BVOC emissions as stress impacts, we found that high temperatures decreased the de novo emissions of monoterpenes, sesquiterpenes and phenolic BVOC. This behaviour was independent of the tree species and whether the de novo emissions were constitutive or induced by biotic stress.

    In contrast, application of thermal stress to conifers amplified the release of monoterpenes stored in resin ducts of conifers and induced emissions of green leaf volatiles. In particular during insect attack on conifers, the plants showed de novo emissions of sesquiterpenes and phenolic BVOCs, which exceeded constitutive monoterpene emissions from pools. The heat-induced decrease of de novo emissions was larger than the increased monoterpene release caused by damage of resin ducts. For insect-infested conifers the net effect of thermal stress on BVOC emissions could be an overall decrease.

    Global change-induced heat waves may put hard thermal stress on plants. If so, we project that BVOC emissions increase is more than predicted by models only in areas predominantly covered with conifers that do not emit high amounts of sesquiterpenes and phenolic BVOCs. Otherwise overall effects of high temperature stress will be lower increases of BVOC emissions than predicted by algorithms that do

  6. Performance characteristics and parametric optimization of an irreversible magnetic Ericsson heat-pump

    International Nuclear Information System (INIS)

    Wei Fang; Lin Guoxing; Chen Jincan; Brueck, Ekkes

    2011-01-01

    Taking into account the finite-rate heat transfer in the heat-transfer processes, heat leak between the two external heat reservoirs, regenerative loss, regeneration time, and internal irreversibility due to dissipation of the cycle working substance, an irreversible magnetic Ericsson heat-pump cycle is presented. On the basis of the thermodynamic properties of magnetic materials, the performance characteristics of the irreversible magnetic Ericsson heat-pump are investigated and the relationship between the optimal heating load and the coefficient of performance (COP) is derived. Moreover, the maximum heating load and the corresponding COP as well as the maximum COP and the corresponding heating load are obtained. Furthermore, the other optimal performance characteristics are discussed in detail. The results obtained here may provide some new information for the optimal parameter design and the development of real magnetic Ericsson heat-pumps. -- Research Highlights: →The effects of multi-irreversibilities on the performance of a magnetic heat-pump are revealed. →Mathematical expressions of the heating load and the COP are derived and the optimal performance and operating parameters are analyzed and discussed. →Several important performance bounds are determined.

  7. Ecological optimization and performance study of irreversible Stirling and Ericsson heat engines

    Science.gov (United States)

    Tyagi, S. K.; Kaushik, S. C.; Salhotra, R.

    2002-10-01

    The concept of finite time thermodynamics is used to determine the ecological function of irreversible Stirling and Ericsson heat engine cycles. The ecological function is defined as the power output minus power loss (irreversibility), which is the ambient temperature times, the entropy generation rate. The ecological function is maximized with respect to cycle temperature ratio and the expressions for the corresponding power output and thermal efficiency are derived at the optimal operating conditions. The effect of different operating parameters, the effectiveness on the hot, cold and the regenerative side heat exchangers, the cycle temperature ratio, heat capacitance ratio and the internal irreversibility parameter on the maximum ecological function are studied. It is found that the effect of regenerator effectiveness is more than the hot and cold side heat exchangers and the effect of the effectiveness on cold side heat exchanger is more than the effectiveness on the hot side heat exchanger on the maximum ecological function. It is also found that the effect of internal irreversibility parameter is more than the other parameters not only on the maximum ecological function but also on the corresponding power output and the thermal efficiency.

  8. Ecological optimization and performance study of irreversible Stirling and Ericsson heat engines

    International Nuclear Information System (INIS)

    Tyagi, S K; Kaushik, S C; Salhotra, R

    2002-01-01

    The concept of finite time thermodynamics is used to determine the ecological function of irreversible Stirling and Ericsson heat engine cycles. The ecological function is defined as the power output minus power loss (irreversibility), which is the ambient temperature times, the entropy generation rate. The ecological function is maximized with respect to cycle temperature ratio and the expressions for the corresponding power output and thermal efficiency are derived at the optimal operating conditions. The effect of different operating parameters, the effectiveness on the hot, cold and the regenerative side heat exchangers, the cycle temperature ratio, heat capacitance ratio and the internal irreversibility parameter on the maximum ecological function are studied. It is found that the effect of regenerator effectiveness is more than the hot and cold side heat exchangers and the effect of the effectiveness on cold side heat exchanger is more than the effectiveness on the hot side heat exchanger on the maximum ecological function. It is also found that the effect of internal irreversibility parameter is more than the other parameters not only on the maximum ecological function but also on the corresponding power output and the thermal efficiency

  9. How to account for irreversibility in integrated assessment of climate change?

    International Nuclear Information System (INIS)

    Ha Duong, M.

    1998-04-01

    How to account for irreversibility in integrated assessment of climate change? This Ph. D. thesis in Economics balances discounting, technical progress and the inertia of existing capital stock against uncertainty and the inertia of socio-economic systems to examine the issue of near term limitations of greenhouse gases emissions. After a general overview in chapter 2, and a more historical presentation of the debates in chapter 3, chapter 4 proceeds to review a large number of integrated assessment models. Chapter 5 introduces a Model on the Dynamics of Inertia and Adaptability of energy systems: DIAM, used to discuss how much previous studies might have overestimated the long term costs of CO 2 limitations and underestimated adjustment costs. It shows that, given a target date for atmospheric CO 2 concentration stabilisation, a higher inertia implies a lower optimal concentration trajectory. In a sequential decision framework, chapter 6 shows that current uncertainties about which CO 2 concentration ceiling would not present dangerous interference with the climate system justifies precautionary action. Finally, chapter 7 uses the irreversibility effect theory to define formally situations of decision under controversy and compare the irreversibility of CO 2 accumulation with the irreversibility of investments needed to moderate it. An option value for greenhouse gases emissions limitations is computed. (author)

  10. Irreversible thermodynamics of dark energy on the entropy-corrected apparent horizon

    Energy Technology Data Exchange (ETDEWEB)

    Karami, K; Sahraei, N [Department of Physics, University of Kurdistan, Pasdaran Street, Sanandaj (Iran, Islamic Republic of); Jamil, M, E-mail: KKarami@uok.ac.i, E-mail: mjamil@camp.nust.edu.p [Center for Advanced Mathematics and Physics (CAMP), National University of Sciences and Technology (NUST), Islamabad (Pakistan)

    2010-10-15

    We study the irreversible (non-equilibrium) thermodynamics of the Friedmann-Robertson-Walker (FRW) universe containing only dark energy. Using the modified entropy-area relation that is motivated by loop quantum gravity, we calculate the entropy-corrected form of the apparent horizon of the FRW universe.

  11. Pulpitis irreversible como forma de presentación de un odontoma

    OpenAIRE

    Berástegui, Esther; Buenechea Imaz, Ramón

    1997-01-01

    Se presenta un caso de odontoma compuesto que provocó pulpitis irreversible en el incisivo central superior derecho (1,1) en una joven de 20 años. El tratamiento fue la biopulpectomía total y extirpación quirúrgica del tumor.

  12. Unifying principles of irreversibility minimization for efficiency maximization in steady-flow chemically-reactive engines

    International Nuclear Information System (INIS)

    Ramakrishnan, Sankaran; Edwards, Christopher F.

    2014-01-01

    Systems research has led to the conception and development of various steady-flow, chemically-reactive, engine cycles for stationary power generation and propulsion. However, the question that remains unanswered is: What is the maximum-efficiency steady-flow chemically-reactive engine architecture permitted by physics? On the one hand the search for higher-efficiency cycles continues, often involving newer processes and devices (fuel cells, carbon separation, etc.); on the other hand the design parameters for existing cycles are continually optimized in response to improvements in device engineering. In this paper we establish that any variation in engine architecture—parametric change or process-sequence change—contributes to an efficiency increase via one of only two possible ways to minimize total irreversibility. These two principles help us unify our understanding from a large number of parametric analyses and cycle-optimization studies for any steady-flow chemically-reactive engine, and set a framework to systematically identify maximum-efficiency engine architectures. - Highlights: • A unified thermodynamic model to study chemically-reactive engine architectures is developed. • All parametric analyses of efficiency are unified by two irreversibility-minimization principles. • Variations in internal energy transfers yield a net work increase that is greater than engine irreversibility reduced. • Variations in external energy transfers yield a net work increase that is lesser than engine irreversibility reduced

  13. Irreversibility and multiplicity: two criteria for the disposal of nuclear wastes

    International Nuclear Information System (INIS)

    Rochlin, G.

    1976-01-01

    Two criteria are suggested for comparing waste management methods: technical irreversibility and site multiplicity. These criteria can be used to reduce future risk in the face of inherent uncertainty and to provide for safe disposal without requiring guaranteed future ability to recognize, detect or repair areas of failure

  14. Herbivore regulation and irreversible vegetation change in semi-arid grazing systems

    NARCIS (Netherlands)

    Van de Koppel, J.; Rietkerk, M.

    2000-01-01

    Models made to explain sudden and irreversible vegetation shifts in semi-arid grasslands typically assume that herbivore density is independent of the state of the vegetation, e.g., under the control of humans. We relax this assumption and investigate the mathematical implications of

  15. A comparison of the anesthetic efficacy of articaine and lidocaine in patients with irreversible pulpitis.

    Science.gov (United States)

    Tortamano, Isabel Peixoto; Siviero, Marcelo; Costa, Carina Gisele; Buscariolo, Inês Aparecida; Armonia, Paschoal Laércio

    2009-02-01

    The purpose of the present study was to compare the anesthetic efficacy of 4% articaine with 1:100,000 epinephrine with that of 2% lidocaine with 1:100,000 epinephrine during pulpectomy in patients with irreversible pulpitis in mandibular posterior teeth. Forty volunteers, patients with irreversible pulpitis admitted to the Emergency Center of the School of Dentistry at the University of São Paulo, randomly received a conventional inferior alveolar nerve block containing 3.6 mL of either 4% articaine with 1:100,000 epinephrine or 2% lidocaine with 1:100,000 epinephrine. During the subsequent pulpectomy, we recorded the patients' subjective assessments of lip anesthesia, the absence/presence of pulpal anesthesia through electric pulp stimulation, and the absence/presence of pain through a verbal analogue scale. All tested patients reported lip anesthesia after the application of either inferior alveolar nerve block. Regarding pulpal anesthesia success as measured with the pulp tester, the lidocaine solution had a higher success rate (70%) than the articaine solution (65%). For patients reporting none or mild pain during pulpectomy, the success rate of the articaine solution (65%) was higher than that of the lidocaine solution (45%). Yet, none of the observed differences between articaine and lidocaine were statistically significant. Apparently, therefore, both local anesthetic solutions had similar effects on the patients with irreversible pulpitis in mandibular posterior teeth. Neither of the solutions, however, resulted in an effective pain control during irreversible pulpitis treatments.

  16. Modelling plastic deformation of metals over a wide range of strain rates using irreversible thermodynamics

    NARCIS (Netherlands)

    Huang, M.; Rivera-Diaz-del-Castillo, P.E.J.; Bouaziz, O.; Van der Zwaag, S.

    2009-01-01

    Based on the theory of irreversible thermodynamics, the present work proposes a dislocation-based model to describe the plastic deformation of FCC metals over wide ranges of strain rates. The stress-strain behaviour and the evolution of the average dislocation density are derived. It is found that

  17. Revisiting the Glansdorff–Prigogine criterion for stability within irreversible thermodynamics

    Czech Academy of Sciences Publication Activity Database

    Maes, C.; Netočný, Karel

    2015-01-01

    Roč. 159, č. 6 (2015), s. 1286-1299 ISSN 0022-4715 R&D Projects: GA ČR GAP204/12/0897 Institutional support: RVO:68378271 Keywords : irreversible processes * thermodynamic stability * excess entropy production * nonequilibrium free energy * Clausius heat theorem Subject RIV: BE - Theoretical Physics Impact factor: 1.537, year: 2015

  18. Thermodynamics of Irreversible Processes. Physical Processes in Terrestrial and Aquatic Ecosystems, Transport Processes.

    Science.gov (United States)

    Levin, Michael; Gallucci, V. F.

    These materials were designed to be used by life science students for instruction in the application of physical theory to ecosystem operation. Most modules contain computer programs which are built around a particular application of a physical process. This module describes the application of irreversible thermodynamics to biology. It begins with…

  19. Wall heat flux influence on the thermodynamic optimisation of irreversibilities of a circulating fluidised bed combustor

    CSIR Research Space (South Africa)

    Baloyi, J

    2016-07-01

    Full Text Available In the study the comparison of irreversibilities was done when the wall condition of the combustor was changed from adiabatic to negative heat flux, for incoming air temperature of 400 K. The reactant mixture of solid pitch pine wood fuel and air...

  20. Site-specific properties and irreversible vegetation changes in semi-arid grazing systems

    NARCIS (Netherlands)

    Rietkerk, M; vandenBosch, F; vandeKoppel, J

    1997-01-01

    There is an urgent need to develop a mechanistic understanding of how site-specific properties can lead to irreversible vegetation changes. We show, by means of a bifurcation analysis of two mathematical models, how site-specific properties determine the resilience of vegetation changes in semi-arid

  1. Site-specific properties and irreversible vegetation changes in semi-arid grazing systems

    NARCIS (Netherlands)

    Rietkerk, M.G.; Bosch, F. van den; Koppel, J. van de

    1997-01-01

    There is an urgent need to develop a mechanistic understanding of how site-specific properties can lead to irreversible vegetation changes. We show, by means of a bifurcation analysis of two mathematica1 models, how site-specific properties determine the resilience of vegetation changes in

  2. Thermal Energy during Irreversible Electroporation and the Influence of Different Ablation Parameters

    NARCIS (Netherlands)

    van den Bos, Willemien; Scheffer, Hester J.; Vogel, Jantien A.; Wagstaff, Peter G. K.; de Bruin, Daniel M.; de Jong, Marcus C.; van Gemert, Martin J. C.; de La Rosette, Jean J. M. C. H.; Meijerink, Martijn R.; Klaessens, John H.; Verdaasdonk, Rudolf M.

    2016-01-01

    Irreversible electroporation (IRE) uses high-voltage electric fields to achieve cell death. Although the mechanism of IRE is mainly designated as nonthermal, development of secondary Joule heating is inevitable. The study purpose was to gain understanding of temperature development and distribution

  3. Quantum thermodynamics: Microscopic foundations of entropy and of entropy generation by irreversibility

    Directory of Open Access Journals (Sweden)

    Beretta, Gian Paolo

    2008-02-01

    Full Text Available What is the physical significance of entropy? What is the physical origin of irreversibility? Do entropy and irreversibility exist only for complex and macroscopic systems? Most physicists still accept and teach that the rationalization of these fundamental questions is given by Statistical Mechanics. Indeed, for everyday laboratory physics, the mathematical formalism of Statistical Mechanics (canonical and grand-canonical, Boltzmann, Bose-Einstein and Fermi-Dirac distributions allows a successful description of the thermodynamic equilibrium properties of matter, including entropy values. However, as already recognized by Schrodinger in 1936, Statistical Mechanics is impaired by conceptual ambiguities and logical inconsistencies, both in its explanation of the meaning of entropy and in its implications on the concept of state of a system. An alternative theory has been developed by Gyftopoulos, Hatsopoulos and the present author to eliminate these stumbling conceptual blocks while maintaining the mathematical formalism so successful in applications. To resolve both the problem of the meaning of entropy and that of the origin of irreversibility we have built entropy and irreversibility into the laws of microscopic physics. The result is a theory, that we call Quantum Thermodynamics, that has all the necessary features to combine Mechanics and Thermodynamics uniting all the successful results of both theories, eliminating the logical inconsistencies of Statistical Mechanics and the paradoxes on irreversibility, and providing an entirely new perspective on the microscopic origin of irreversibility, nonlinearity (therefore including chaotic behavior and maximal-entropy-generation nonequilibrium dynamics. In this paper we discuss the background and formalism of Quantum Thermodynamics including its nonlinear equation of motion and the main general results. Our objective is to show in a not-too-technical manner that this theory provides indeed a

  4. Pinning and irreversibility in superconducting bulk MgB{sub 2} with added nanodiamonds

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, Anurag [Superconductivity and Cryogenics Division, National Physical Laboratory (CSIR), New Delhi-110012 (India); Narlikar, A V, E-mail: anurag@mail.nplindia.ernet.i [UGC-DAE Consortium for Scientific Research, University Campus, Khandwa Road, Indore-452017, MP (India)

    2009-12-15

    Resistance, R(T), and magnetization, M(B), studies on superconducting bulk MgB{sub 2} samples containing nanodiamonds (ND) as additives (wt% of ND: x = 0%, 1%, 3%, 5%, 7% and 10%) were recently published in two articles (Vajpayee et al 2007 Supercond. Sci. Technol. 20 S155, Vajpayee et al 2008 J. Appl. Phys. 103 07C708). The main observations reported were significant improvements in the critical current density J{sub c}(B), irreversibility line B{sub irr}(T) and upper critical field B{sub c2}(T) with ND addition. However, a closer look shows that as regards the potential of this technologically important material at higher magnetic fields and temperatures, there is still a lot of room for improvement. With that in mind we revisit the R(T) and M(B) data and analyze them, in the present work. We show that, despite ND addition, J{sub c} depends strongly on B in the high field region and tends to vanish at irreversibility lines that lie deep, i.e. at around 0.3 B{sub c2}(T), in the B-T phase diagram. The irreversibility lines, determined by R(T){yields}0 in the presence of B, are found to lie at around 0.5 B{sub c2}(T) in the phase diagram. These results for pinning and irreversibility lines are discussed in the light of various models such as those of surface sheath superconductivity, magnetically introduced percolation in polycrystalline MgB{sub 2}, thermally assisted flux motion (TAFM) and a modified flux line shear mechanism. Our analysis hints at TAFM and weak pinning channels with distributed superconducting properties percolating in our samples determining the irreversibility and pinning properties.

  5. Multi-objective optimization of an irreversible Stirling cryogenic refrigerator cycle

    International Nuclear Information System (INIS)

    Ahmadi, Mohammad H.; Ahmadi, Mohammad Ali; Mohammadi, Amir H.; Feidt, Michel; Pourkiaei, Seyed Mohsen

    2014-01-01

    Highlights: • A parametric investigation of irreversible Stirling cryogenic refrigerator cycles is presented. • Both internal and external irreversibilities are included in this study, moreover, heat capacities of external reservoirs are involved. • Multi-objective evolutionary algorithm based on NSGA-II approach is utilized. • Three robust decision making approaches are utilized to determine final optimum solution. - Abstract: The main aim of this research article is a parametric demonstration of irreversible Stirling cryogenic refrigerator cycles that includes irreversibilities such as external and internal irreversibilities. In addition, through this study, finite heat capacities of external reservoirs are considered accordingly. To reach the addressed goal of this research, three objective functions that include the input power of the Stirling refrigerator, the coefficient of performance (COP) and cooling load (R L ) have been involved in optimization process simultaneously. The first aforementioned objective function has to minimize; the rest objective functions, on the other hand, have to maximize in parallel optimization process. Developed multi objective evolutionary approaches (MOEAs) based on NSGA-II algorithm is implemented throughout this work. Moreover, cold-side’s effectiveness of the heat exchanger, hot-side’s effectiveness of the heat exchanger, heat source’s heat capacitance rate, heat sink’s capacitance rate, temperature ratio ((T h )/(T c ) ), temperature of cold side are assigned as decision variables for decision making procedure. To gain a robust decision, different decision making approaches that include TOPSIS, LINMAP and fuzzy Bellman–Zadeh are used. Pareto optimal frontier was determined precisely and then three final outputs have been gained by means of the mentioned decision making approaches

  6. The analysis of irreversibility, uncertainty and dynamic technical inefficiency on the investment decision in the Spanish olive sector

    NARCIS (Netherlands)

    Lambarraa, Fatima; Stefanou, Spiro; Gil, José M.

    2016-01-01

    This study addresses irreversible investment decision-making in the context of uncertainty when allowing for inefficiency to be transmitted over time. Both irreversibility and persistence in technical inefficiency can lead to sluggish adjustment of quasi-fixed factors of production. The context

  7. A Community Organizing Case Study: An Analysis of Cap-It's Strategy to Prevent the Location of a Toxic Waste Incinerator in Their Community.

    Science.gov (United States)

    Jacobs, J

    1992-01-01

    With the great proliferation of chemical manufacturing in the past half-century, the dilemma of dealing with the waste produced has become an increasing problem facing communities. One method that is gaining increased acceptance by both government and industry is incineration. Many citizens have formed groups to protest these facilities because of their concerns about health risks, especially exposure to carcinogens. This case study profiles one such group, CAP-IT, a collection of middle-class residents living in a small working-class town and their successful battle to prevent the siting of a hazardous waste incinerator. CAP-IT's strategy will be critiqued using methods advanced by Lee Staples, Nicholas Freudenburg and Kurt Lewin to demonstrate the power of community organizing activities.

  8. Using forum play to prevent abuse in health care organizations: A qualitative study exploring potentials and limitations for learning.

    Science.gov (United States)

    Brüggemann, A Jelmer; Persson, Alma

    2016-01-01

    Abuse in health care organizations is a pressing issue for caregivers. Forum play, a participatory theater model, has been used among health care staff to learn about and work against abuse. This small-scale qualitative study aims to explore how forum play participants experience the potentials and limitations of forum play as an educational model for continued professional learning at a hospital clinic. Fifteen of 41 members of staff of a Swedish nephrology clinic, primarily nurses, voluntarily participated in either one or two forum play workshops, where they shared experiences and together practiced working against abuse in everyday health care situations. Interviews were conducted after the workshops with 14 of the participants, where they were asked to reflect on their own and others' participation or nonparticipation, and changes in their individual and collective understanding of abuse in health care. Before the workshops, the informants were either hesitant or very enthusiastic toward the drama-oriented form of learning. Afterward, they all agreed that forum play was a very effective way of individual as well as collective learning about abuse in health care. However, they saw little effect on their work at the clinic, primarily understood as a consequence of the fact that many of their colleagues did not take part in the workshops. This study, based on the analysis of forum play efforts at a single hospital clinic, suggests that forum play can be an innovative educational model that creates a space for reflection and learning in health care practices. It might be especially fruitful when a sensitive topic, such as abuse in health care, is the target of change. However, for the effects to reach beyond individual insights and a shared understanding among a small group of participants, strategies to include all members of staff need to be explored.

  9. Reversible and irreversible impacts of greenhouse gas emissions in multi-century projections with the NCAR global coupled carbon cycle-climate model

    Energy Technology Data Exchange (ETDEWEB)

    Froelicher, Thomas L.; Joos, Fortunat [University of Bern, Climate and Environmental Physics, Physics Institute, Bern (Switzerland); University of Bern, Oeschger Centre for Climate Change Research, Bern (Switzerland)

    2010-12-15

    The legacy of historical and the long-term impacts of 21st century greenhouse gas emissions on climate, ocean acidification, and carbon-climate feedbacks are investigated with a coupled carbon cycle-climate model. Emission commitment scenarios with zero emissions after year 2100 and 21st century emissions of 1,800, 900, and 0 gigatons of carbon are run up to year 2500. The reversibility and irreversibility of impacts is quantified by comparing anthropogenically-forced regional changes with internal, unforced climate variability. We show that the influence of historical emissions and of non-CO{sub 2} agents is largely reversible on the regional scale. Forced changes in surface temperature and precipitation become smaller than internal variability for most land and ocean grid cells in the absence of future carbon emissions. In contrast, continued carbon emissions over the 21st century cause irreversible climate change on centennial to millennial timescales in most regions and impacts related to ocean acidification and sea level rise continue to aggravate for centuries even if emissions are stopped in year 2100. Undersaturation of the Arctic surface ocean with respect to aragonite, a mineral form of calcium carbonate secreted by marine organisms, is imminent and remains widespread. The volume of supersaturated water providing habitat to calcifying organisms is reduced from preindustrial 40 to 25% in 2100 and to 10% in 2300 for the high emission case. We conclude that emission trading schemes, related to the Kyoto Process, should not permit trading between emissions of relatively short-lived agents and CO{sub 2} given the irreversible impacts of anthropogenic carbon emissions. (orig.)

  10. Resistance patterns and outcomes in intensive care unit (ICU)-acquired pneumonia. Validation of European Centre for Disease Prevention and Control (ECDC) and the Centers for Disease Control and Prevention (CDC) classification of multidrug resistant organisms.

    Science.gov (United States)

    Martin-Loeches, Ignacio; Torres, Antonio; Rinaudo, Mariano; Terraneo, Silvia; de Rosa, Francesca; Ramirez, Paula; Diaz, Emili; Fernández-Barat, Laia; Li Bassi, Gian Luigi; Ferrer, Miquel

    2015-03-01

    Bacterial resistance has become a major public health problem. To validate the definition of multidrug-resistant organisms (MDRO) based on the European Centre for Disease Prevention and Control (ECDC) and the Centers for Disease Control and Prevention (CDC) classification. Prospective, observational study in six medical and surgical Intensive-Care-Units (ICU) of a University hospital. Three-hundred-and-forty-three patients with ICU-acquired pneumonia (ICUAP) were prospectively enrolled, 140 patients had no microbiological confirmation (41%), 82 patients (24%) developed ICUAP for non-MDRO, whereas 121 (35%) were MDROs. Non-MDRO, MDRO and no microbiological confirmation patients did not present either a significant different previous antibiotic use (p 0.18) or previous hospital admission (p 0.17). Appropriate antibiotic therapy was associated with better ICU survival (105 [92.9%] vs. 74 [82.2%]; p = 0.03). An adjusted multivariate regression logistic analysis identified that only MDRO had a higher ICU-mortality than non-MDRO and no microbiological confirmation patients (OR 2.89; p < 0.05; 95% CI for Exp [β]. 1.02-8.21); Patients with MDRO ICUAP remained in ICU for a longer period than MDRO and no microbiological confirmation respectively (p < 0.01) however no microbiological confirmation patients had more often antibiotic consumption than culture positive ones. Patients who developed ICUAP due to MDRO showed a higher ICU-mortality than non-MDRO ones and use of ICU resources. No microbiological confirmation patients had more often antibiotic consumption than culture positive patients. Risk factors for MDRO may be important for the selection of initial antimicrobial therapy, in addition to local epidemiology. Copyright © 2014 The British Infection Association. Published by Elsevier Ltd. All rights reserved.

  11. Factors influencing the implementation of organized physical activity and fruit and vegetable snacks in the HOP'N after-school obesity prevention program.

    Science.gov (United States)

    Hastmann, Tanis J; Bopp, Melissa; Fallon, Elizabeth A; Rosenkranz, Richard R; Dzewaltowski, David A

    2013-01-01

    To identify barriers and facilitators for improving the after-school organized physical activity (PA) and snack quality. After-school staff (Year 1, n = 20; Year 2, n = 17) participated in qualitative, semistructured interviews about the implementation of an after-school obesity prevention intervention. Interviews were recorded, transcribed, coded for common themes, and analyzed using NVivo software. Several factors influencing implementation of PA and fruit and vegetable (FV) consumption were revealed. Facilitators for PA included: staff training, equipment/gym space, and scheduling organized PA. Physical activity barriers included prioritizing PA and lack of school administration support. Fruit and vegetable facilitators included requesting healthier snacks. Fruit and vegetable barriers included cost and low priority of snack. The success of improving after-school PA and FV snack quality is dependent on many factors, including several organizational system and staff variables. Future research should focus on systemic changes in the after-school environment to increase the priority of daily PA and a healthy snack. Copyright © 2013 Society for Nutrition Education and Behavior. Published by Elsevier Inc. All rights reserved.

  12. Labile phytochrome and photoperiodic flower induction in Pharbitis nil Chois. The irreversible phytochrome hypothesis

    Directory of Open Access Journals (Sweden)

    Mariusz Cymerski

    2014-01-01

    Full Text Available Seedlings of Pharbitis nil cultivated under non-inductive conditions of white light were subjected to generative induction applying one 16-hour-long period of inductive night. During the eighth hour the night was interrupted with 1 min of red light pulse which completely inhibited the flowering. Treating the plants with KCN blocked the inhibiting effect of red light. Because KCN lowers considerably the rate of destruction of labile Pfd in some plant systems, it seems probable that red light night-break irradiation (without KCN, which blocked the flowering, leads also to the accumulation of unknown Pfd destruction products (irreversible phytochrome. It also suggests that it is not the labile PfrI itself but the products of its irreversible transformation that could be active in the photoperiodic control of flowering.

  13. Capital dissipation minimization for a class of complex irreversible resource exchange processes

    Science.gov (United States)

    Xia, Shaojun; Chen, Lingen

    2017-05-01

    A model of a class of irreversible resource exchange processes (REPes) between a firm and a producer with commodity flow leakage from the producer to a competitive market is established in this paper. The REPes are assumed to obey the linear commodity transfer law (LCTL). Optimal price paths for capital dissipation minimization (CDM) (it can measure economic process irreversibility) are obtained. The averaged optimal control theory is used. The optimal REP strategy is also compared with other strategies, such as constant-firm-price operation and constant-commodity-flow operation, and effects of the amount of commodity transferred and the commodity flow leakage on the optimal REP strategy are also analyzed. The commodity prices of both the producer and the firm for the CDM of the REPes with commodity flow leakage change with the time exponentially.

  14. Irreversible binding of o,p'-DDD in interrenal cells of Atlantic cod (Gadus morhua).

    Science.gov (United States)

    Lindhe, Orjan; Brandt, Ingvar; Christiansen, Jørgen Schou; Ingebrigtsen, Kristian

    2003-03-01

    Precision-cut tissue slices of the anterior kidney from Atlantic cod (Gadus morhua) were prepared with a Krumdieck tissue slicer and exposed to 2-(2-chlorophenyl)-2-(4-chloro-(14C)phenyl)-1,1-dichlorethane (o,p(')-[14C]DDD) in vitro. Microautoradiography revealed irreversible o,p(')-DDD-derived binding confined to the glucocorticoid producing interrenal cells (adrenocortical analogues). This cell-selective binding was confirmed by means of autoradiography at different levels of resolution on Atlantic cod administered o,p(')-[14C]DDD intragastrically. The results provide evidence for a site-specific metabolic activation and irreversible binding of o,p(')-DDD in the interrenal cells, which, in turn, may modify glucocorticoid homeostasis.

  15. Irreversible and irretrievable commitments of material resources (Revision 1) - June 1976

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    In accordance with 10 CFR Part 51, Licensing and Regulatory Policy and Procedures for Environmental Protection, applicants are required to discuss any irreversible and irretrievable commitments of resources that would be involved in a proposed action, should it be implemented. The construction and operation of nuclear power stations involve commitments of such resources as water, fuel and materials. The guide presented identifies a report on material resources that forms a basis acceptable to the NRC staff for required discussions of irreversible and irretrievable commitments of material resources involved in the construction of a 1000 MWe pressurized water reactor. The guide describes numerical estimates useful in all such discussions. It also provides methods of computation that may be referenced

  16. Linear irreversible thermodynamics and Onsager reciprocity for information-driven engines

    Science.gov (United States)

    Yamamoto, Shumpei; Ito, Sosuke; Shiraishi, Naoto; Sagawa, Takahiro

    2016-11-01

    In the recent progress in nonequilibrium thermodynamics, information has been recognized as a kind of thermodynamic resource that can drive thermodynamic current without any direct energy injection. In this paper, we establish the framework of linear irreversible thermodynamics for a broad class of autonomous information processing. In particular, we prove that the Onsager reciprocity holds true with information: The linear response matrix is well-defined and is shown symmetric with both of the information affinity and the conventional thermodynamic affinity. As an application, we derive a universal bound for the efficiency at maximum power for information-driven engines in the linear regime. Our result reveals the fundamental role of information flow in linear irreversible thermodynamics.

  17. Long Memory and Structural Breaks in Realized Volatility: An Irreversible Markov Switching Approach

    DEFF Research Database (Denmark)

    Nonejad, Nima

    This paper proposes a model that simultaneously captures long memory and structural breaks. We model structural breaks through irreversible Markov switching or so-called change-point dynamics. The parameters subject to structural breaks and the unobserved states which determine the position...... to daily S&P 500 data, one finds strong evidence of three structural breaks. The evidence of these breaks is robust to different specifications including a GARCH specification for the conditional variance of volatility....

  18. Microbiome of Deep Dentinal Caries Lesions in Teeth with Symptomatic Irreversible Pulpitis.

    Science.gov (United States)

    Rôças, Isabela N; Alves, Flávio R F; Rachid, Caio T C C; Lima, Kenio C; Assunção, Isauremi V; Gomes, Patrícia N; Siqueira, José F

    2016-01-01

    This study used a next-generation sequencing approach to identify the bacterial taxa occurring in the advanced front of caries biofilms associated with pulp exposure and irreversible pulpitis. Samples were taken from the deepest layer of dentinal caries lesions associated with pulp exposure in 10 teeth diagnosed with symptomatic irreversible pulpitis. DNA was extracted and the microbiome was characterized on the basis of the V4 hypervariable region of the 16S rRNA gene by using paired-end sequencing on Illumina MiSeq device. Bacterial taxa were mapped to 14 phyla and 101 genera composed by 706 different OTUs. Three phyla accounted for approximately 98% of the sequences: Firmicutes, Actinobacteria and Proteobacteria. These phyla were also the ones with most representatives at the species level. Firmicutes was the most abundant phylum in 9/10 samples. As for genera, Lactobacillus accounted for 42.3% of the sequences, followed by Olsenella (13.7%), Pseudoramibacter (10.7%) and Streptococcus (5.5%). Half of the samples were heavily dominated by Lactobacillus, while in the other half lactobacilli were in very low abundance and the most dominant genera were Pseudoramibacter, Olsenella, Streptococcus, and Stenotrophomonas. High bacterial diversity occurred in deep dentinal caries lesions associated with symptomatic irreversible pulpitis. The microbiome could be classified according to the relative abundance of Lactobacillus. Except for Lactobacillus species, most of the highly prevalent and abundant bacterial taxa identified in this study have been commonly detected in infected root canals. The detected taxa can be regarded as candidate pathogens for irreversible pulpitis and possibly the pioneers in pulp invasion to initiate endodontic infection.

  19. Microbiome of Deep Dentinal Caries Lesions in Teeth with Symptomatic Irreversible Pulpitis.

    Directory of Open Access Journals (Sweden)

    Isabela N Rôças

    Full Text Available This study used a next-generation sequencing approach to identify the bacterial taxa occurring in the advanced front of caries biofilms associated with pulp exposure and irreversible pulpitis. Samples were taken from the deepest layer of dentinal caries lesions associated with pulp exposure in 10 teeth diagnosed with symptomatic irreversible pulpitis. DNA was extracted and the microbiome was characterized on the basis of the V4 hypervariable region of the 16S rRNA gene by using paired-end sequencing on Illumina MiSeq device. Bacterial taxa were mapped to 14 phyla and 101 genera composed by 706 different OTUs. Three phyla accounted for approximately 98% of the sequences: Firmicutes, Actinobacteria and Proteobacteria. These phyla were also the ones with most representatives at the species level. Firmicutes was the most abundant phylum in 9/10 samples. As for genera, Lactobacillus accounted for 42.3% of the sequences, followed by Olsenella (13.7%, Pseudoramibacter (10.7% and Streptococcus (5.5%. Half of the samples were heavily dominated by Lactobacillus, while in the other half lactobacilli were in very low abundance and the most dominant genera were Pseudoramibacter, Olsenella, Streptococcus, and Stenotrophomonas. High bacterial diversity occurred in deep dentinal caries lesions associated with symptomatic irreversible pulpitis. The microbiome could be classified according to the relative abundance of Lactobacillus. Except for Lactobacillus species, most of the highly prevalent and abundant bacterial taxa identified in this study have been commonly detected in infected root canals. The detected taxa can be regarded as candidate pathogens for irreversible pulpitis and possibly the pioneers in pulp invasion to initiate endodontic infection.

  20. Macroscopic irreversibility and microscopic paradox: A Constructal law analysis of atoms as open systems

    OpenAIRE

    Umberto Lucia

    2016-01-01

    The relation between macroscopic irreversibility and microscopic reversibility is a present unsolved problem. Constructal law is introduced to develop analytically the Einstein?s, Schr?dinger?s, and Gibbs? considerations on the interaction between particles and thermal radiation (photons). The result leads to consider the atoms and molecules as open systems in continuous interaction with flows of photons from their surroundings. The consequent result is that, in any atomic transition, the ene...

  1. Conducts of disinfection, pouring and storage of irreversible hydrocolloid impressions by undergraduate students

    Directory of Open Access Journals (Sweden)

    Thalisson Saymo de Oliveira SILVA

    Full Text Available Abstract Introduction Obtaining dental models that accurately represent the molded oral tissue requires professional attention, especially when using irreversible hydrocolloid as a molding material. Objective To evaluate the conducts of undergraduate dental students at different internships for the disinfecting procedures, pouring, and storage of irreversible hydrocolloid impressions. Material and method This is an observational, cross-sectional and descriptive study with a census sample of 89 students enrolled in the supervised internships I, II, III and IV. Data collection was performed using a structured questionnaire containing eight questions. Data were analyzed at the 5% significance level. Result Most of the students (88.8% performed the disinfection procedure, for which the most widely used method (64.6% was the application of sodium hypochlorite 1% spray stored in a sealed container. The most common disinfection time was 10 minutes (86.1%. Students in the early internships performed better in regard to the proportion of water/plaster to be used compared with students in the final internships. At all internships, pouring and storage of the ensemble of mold and model were neglected during the setting reaction. There was a statistically significant association between the stage and the disinfection method, the ratio of water/powder and pouring of the model (p<0.05. Conclusion Students exhibited appropriate conduct of disinfection; however, they should be encouraged to use evidence-based clinical practices in order to improve the procedures of pouring and storage of irreversible hydrocolloid molds.

  2. Calcium-Enriched Mixture Pulpotomy of Primary Molar Teeth with Irreversible Pulpitis. A Clinical Study.

    Science.gov (United States)

    Memarpour, Mahtab; Fijan, Soleiman; Asgary, Saeed; Keikhaee, Marzieh

    2016-01-01

    To evaluate the outcome of vital pulp therapy in primary teeth with irreversible pulpitis by using calcium-enriched mixture (CEM) cement according to clinical and radiographic assessment. Fifty primary molar teeth with irreversible pulpitis in 50 children aged 6-8 years underwent pulpotomy using CEM cement as the dressing material. Following pulpotomy, pain intensity was evaluated by use of a visual analog scale at 1 and 7 days from the treatment and in clinical appointments at 3, 6 and 12 months after baseline. Radiographic evaluation was performed at 6 and 12 months. Data were analyzed using the McNemar test. A total of 42 children (mean age 7.26 ± 0.82 year) completed the study. After one day treatment 56 % of children reported complete relief of pain and after 7 days 62% reported the same. However, two children complained of increased pain 1 day after treatment. None of the children reported pain in the subsequent appointments. One child complained of tenderness in percussion after 6 months. Pulp canal obliteration was the most common change in the radiographic assessment. There was no significant difference between clinical (92.8%) and radiographic (90.4%) success (p=0.990). Pulpotomy using CEM cement could present a successful treatment in primary molar teeth with irreversible pulpitis.

  3. Calcium-Enriched Mixture Pulpotomy of Primary Molar Teeth with Irreversible Pulpitis. A Clinical Study

    Science.gov (United States)

    Memarpour, Mahtab; Fijan, Soleiman; Asgary, Saeed; Keikhaee, Marzieh

    2016-01-01

    Objectives: To evaluate the outcome of vital pulp therapy in primary teeth with irreversible pulpitis by using calcium-enriched mixture (CEM) cement according to clinical and radiographic assessment. Participants and Methods: Fifty primary molar teeth with irreversible pulpitis in 50 children aged 6-8 years underwent pulpotomy using CEM cement as the dressing material. Following pulpotomy, pain intensity was evaluated by use of a visual analog scale at 1 and 7 days from the treatment and in clinical appointments at 3, 6 and 12 months after baseline. Radiographic evaluation was performed at 6 and 12 months. Data were analyzed using the McNemar test. Results: A total of 42 children (mean age 7.26 ± 0.82 year) completed the study. After one day treatment 56 % of children reported complete relief of pain and after 7 days 62% reported the same. However, two children complained of increased pain 1 day after treatment. None of the children reported pain in the subsequent appointments. One child complained of tenderness in percussion after 6 months. Pulp canal obliteration was the most common change in the radiographic assessment. There was no significant difference between clinical (92.8%) and radiographic (90.4%) success (p=0.990). Conclusion: Pulpotomy using CEM cement could present a successful treatment in primary molar teeth with irreversible pulpitis. PMID:27326265

  4. Coupled Reversible and Irreversible Bistable Switches Underlying TGFβ-induced Epithelial to Mesenchymal Transition

    Science.gov (United States)

    Tian, Xiao-Jun; Zhang, Hang; Xing, Jianhua

    2013-01-01

    Epithelial to mesenchymal transition (EMT) plays an important role in embryonic development, tissue regeneration, and cancer metastasis. Whereas several feedback loops have been shown to regulate EMT, it remains elusive how they coordinately modulate EMT response to TGF-β treatment. We construct a mathematical model for the core regulatory network controlling TGF-β-induced EMT. Through deterministic analyses and stochastic simulations, we show that EMT is a sequential two-step program in which an epithelial cell first is converted to partial EMT then to the mesenchymal state, depending on the strength and duration of TGF-β stimulation. Mechanistically the system is governed by coupled reversible and irreversible bistable switches. The SNAIL1/miR-34 double-negative feedback loop is responsible for the reversible switch and regulates the initiation of EMT, whereas the ZEB/miR-200 feedback loop is accountable for the irreversible switch and controls the establishment of the mesenchymal state. Furthermore, an autocrine TGF-β/miR-200 feedback loop makes the second switch irreversible, modulating the maintenance of EMT. Such coupled bistable switches are robust to parameter variation and molecular noise. We provide a mechanistic explanation on multiple experimental observations. The model makes several explicit predictions on hysteretic dynamic behaviors, system response to pulsed stimulation, and various perturbations, which can be straightforwardly tested. PMID:23972859

  5. How Effective Is Supplemental Intraseptal Anesthesia in Patients with Symptomatic Irreversible Pulpitis?

    Science.gov (United States)

    Webster, Stephen; Drum, Melissa; Reader, Al; Fowler, Sara; Nusstein, John; Beck, Mike

    2016-10-01

    Previous studies have reported high levels of success with intraseptal injection for various dental procedures but provide limited information on the use of the injection during endodontic treatment. Therefore, the purpose of this prospective study was to determine the anesthetic efficacy of the supplemental intraseptal technique in mandibular posterior teeth diagnosed with symptomatic irreversible pulpitis when the conventional inferior alveolar nerve (IAN) block failed. One hundred patients with a diagnosis of symptomatic irreversible pulpitis in a mandibular posterior tooth were recruited. Following profound lip numbness after the administration of the conventional IAN block, endodontic treatment was initiated. Patients still experiencing moderate to severe pain during treatment were administered mesial and distal supplemental intraseptal injections using 0.7 mL 4% articaine with 1:000,000 epinephrine administered with a computer-controlled local anesthetic delivery unit. Success was defined as the ability to perform endodontic access and instrumentation with mild to no pain. Success with the IAN block was achieved in 25% of patients. Supplemental intraseptal injections provided success in 29% of patients. Supplemental intraseptal injections achieved profound pulpal anesthesia in 29% of patients when the IAN block failed. This low level of success would not provide predictable levels of anesthesia for patients requiring emergency endodontic treatment for symptomatic irreversible pulpitis in mandibular posterior teeth. Copyright © 2016 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  6. Endothelial dysfunction and atherosclerosis in children with irreversible pulmonary hypertension due to congenital heart disease

    International Nuclear Information System (INIS)

    Çiftel, Murat; Şimşek, Ayse; Turan, Özlem; Kardelen, Firat; Akçurin, Gayaz; Ertuğ, Halil

    2012-01-01

    To assess endothelial dysfunction and the risk for coronary atherosclerosis in children with irreversible pulmonary hypertension due to congenital heart disease (CHD). The study included 18 cyanotic patients (the mean age was 12.28 ± 3.26 years) who developed irreversible pulmonary hypertension due to cyanotic and acyanotic CHDs, and 18 control patients (the mean age was 11.78 ± 3.00 years). Study groups were compared for flow-mediated dilatation (FMD), carotid intima media thickness (CIMT) and atherosclerotic risk factors. Compared to the control group, the mean FMD was significantly reduced in the cyanotic group (5.26 ± 2.42% and 9.48 ± 2.60%, respectively; P-value < 0.001). No significant difference was observed between the groups in CIMT (0.41 ± 0.08 mm and 0.39 ± 0.06 mm, respectively; P-value = 0.299). The levels of total cholesterol, low-density lipoprotein–cholesterol and very low-density lipoprotein–cholesterol were statistically significantly lower compared tothe control group (P-value = 0.001, 0.006 and 0.014, respectively), whereas no statistically significant difference was found in the levels of high-density lipoprotein–cholesterol and triglycerides (P-value = 0.113 and 0.975, respectively). Systemic endothelial dysfunction in children with irreversible pulmonary hypertension due to CHD was noted but there was no increased risk for atherosclerosis

  7. Parametric optimization of an irreversible magnetic Ericsson refrigerator with finite heat reservoirs

    International Nuclear Information System (INIS)

    Ye, X.M.; Lin, G.X.; Chen, J.C.; Brueck, E.

    2007-01-01

    An irreversible cycle model of magnetic Ericsson refrigerators is established, in which the finite heat capacities of external heat reservoirs, heat-transfer irreversibility, inherent regenerative losses, additional regenerative losses due to thermal resistances and irreversibility inside the magnetic working substances are taken into account. On the basis of the thermodynamic equations of paramagnetic materials, the performance characteristics of the magnetic Ericsson refrigeration cycle are investigated. By using the method of the optimal control theory, the optimal equations between the cooling load and the coefficient of performance and between the cooling load and the power input are derived. Furthermore, the maximum cooling load and the corresponding coefficient of performance, the minimum power input and the optimally operating temperatures of the cyclic working substance are obtained. The optimal operating region of the magnetic Ericsson refrigerator is determined. The results obtained here are closer to the performance characteristics of practical magnetic refrigerators with finite heat reservoirs than those in literature and are helpful to the optimal design and performance improvement of magnetic Ericsson refrigerators

  8. Origin of the irreversibility line in thin YBa2Cu3O7-δ films with and without columnar defects

    International Nuclear Information System (INIS)

    Prozorov, R.; Konczykowski, M.; Schmidt, B.; Yeshurun, Y.; Shaulov, A.; Villard, C.; Koren, G.

    1996-01-01

    We report on measurements of the angular dependence of the irreversibility temperature T irr (θ) in YBa 2 Cu 3 O 7-δ thin films, defined by the onset of a third-harmonic signal and measured by a miniature Hall probe. From the functional form of T irr (θ) we conclude that the origin of the irreversibility line in unirradiated films is a dynamic crossover from an unpinned to a pinned vortex liquid. In irradiated films the irreversibility temperature is determined by the trapping angle. copyright 1996 The American Physical Society

  9. Concerning the study of the irreversible magnetic behaviour of superconductivity; Contribution a l'etude du comportement magnetique irreversible des supraconducteurs

    Energy Technology Data Exchange (ETDEWEB)

    Kuhn, G. [Commissariat a l' Energie Atomique, Grenoble (France). Centre d' Etudes Nucleaires

    1965-03-01

    The influence of the presence of extended lattice defects on the magnetic behaviour has been studied for the case of type I superconductors, such as Re and Ta, and in a more quantitative manner for the type II superconductor niobium. In this case, measurements of the thermal conductivity have given an estimate of the relative concentration of lattice defects in each specimen. These measurements show that the larger the number of lattice defects, the more irreversible becomes the magnetization curve, and the larger becomes the values of the critical current, which is related by a simple model to the magnetization values. Finally, a study by transmission electron microscopy has confirmed on the one hand the diversity of the extended lattice defects and on the other hand has allowed the formulation of several hypothesis on their respective influence. [French] L'influence de la presence de defauts etendus sur le comportement magnetique a ete etudie pour des supraconducteurs de premiere espece, tels que le rhenium et le tantale, et plus quantitativement pour un supraconducteur de deuxieme espece, le niobium. Dans ce cas, des mesures de conductibilite thermique ont permis d'estimer la concentration relative des defauts du reseau dans chaque echantillon. Ces mesures montrent que plus les defauts du reseau sont nombreux, plus la courbe d'aimantation est irreversible, et plus les valeurs du courant critique, reliees par un modele simple aux valeurs de l'aimantation, sont elevees. Enfin une etude par microscopie electronique en transmission - a permis d'une part de constater la diversite des defauts etendus et d'autre part de formuler quelques hypotheses sur leurs influences respectives.

  10. Meta-analysis of endophthalmitis after intravitreal injection of anti-vascular endothelial growth factor agents: causative organisms and possible prevention strategies.

    Science.gov (United States)

    McCannel, Colin A

    2011-04-01

    To report the rates of endophthalmitis and the spectrum of causative organisms after intravitreal injection of anti-vascular endothelial growth factor agents and possible prevention strategies. Meta-analysis of the U.S. literature from 2005 to 2009 reporting endophthalmitis bacterial isolates after intravitreal injection of anti-vascular endothelial growth factor agents and comparison with reports of endophthalmitis bacterial isolates after intraocular surgery in the United States. Endophthalmitis after intravitreal injection occurred in 52 of 105,536 injections (0.049%) (95% confidence interval [CI], 0.038-0.065%). Among 50 cases of endophthalmitis with bacterial culture isolates, 24 (48.0% [95% CI, 34.8-61.5%]) were culture negative and 26 (52% [95% CI, 38.5-65.2%]) were culture positive. Among the 26 culture-positive isolates, causative organisms were coagulase-negative Staphylococcus in 17 cases (65.4% [95% CI, 46.0-80.6%]), Streptococcus species in 8 cases (30.8% [95% CI, 16.5-50.2%]), and Bacillus cereus in 1 case (3.8% [95% CI, 0.9-19.0%]). Streptococcus species were significantly more frequent after intravitreal injection than after intraocular surgery in the Endophthalmitis Vitrectomy Study (29 of 226 isolates, 9.0% [95% CI, 6.3-12.6%], P = 0.005), a report on clear corneal cataract surgery endophthalmitis (6 of 73 isolates, 8.2% [95% CI, 3.9-16.8%], P = 0.022), and a report on postvitrectomy endophthalmitis with no cases of Streptococcus species. Streptococcal isolates are approximately three times more frequent after intravitreal anti-vascular endothelial growth factor injection than after intraocular surgery. Strategies to consider minimizing oropharyngeal droplet transmission may include avoiding talking, coughing, and sneezing or wearing surgical masks.

  11. An analysis of the implementation of PEPFAR's anti-prostitution pledge and its implications for successful HIV prevention among organizations working with sex workers

    Science.gov (United States)

    Ditmore, Melissa Hope; Allman, Dan

    2013-01-01

    Introduction Since 2003, US government funding to address the HIV and AIDS pandemic has been subject to an anti-prostitution clause. Simultaneously, the efficacy of some HIV prevention efforts for sex work in areas receiving US government funding has diminished. This article seeks to explain why. Methods This analysis utilizes a case story approach to build a narrative of defining features of organizations in receipt of funding from the President's Emergency Plan for AIDS Relief (PEPFAR) and other US funding sources. For this analysis, multiple cases were compiled within a single narrative. This helps show restrictions imposed by the anti-prostitution clause, any lack of clarity of guidelines for implementation and ways some agencies, decision-making personnel, and staff on the ground contend with these restrictions. Results Responses to PEPFAR's anti-prostitution clause vary widely and have varied over time. Organizational responses have included ending services for sex workers, gradual phase-out of services, cessation of seeking US government HIV funds and increasing isolation of sex workers. Guidance issued in 2010 did not clarify what was permitted. Implementation and enforcement has been dependent in part on the interpretations of this policy by individuals, including US government representatives and organizational staff. Conclusions Different interpretations of the anti-prostitution clause have led to variations in programming, affecting the effectiveness of work with sex workers. The case story approach proved ideal for working with information like this that is highly sensitive and vulnerable to breach of anonymity because the method limits the potential to betray confidences and sources, and limits the potential to jeopardize funding and thereby jeopardize programming. This method enabled us to use specific examples without jeopardizing the organizations and individuals involved while demonstrating unintended consequences of PEPFAR's anti

  12. Tissue heterogeneity in structure and conductivity contribute to cell survival during irreversible electroporation ablation by "electric field sinks".

    Science.gov (United States)

    Golberg, Alexander; Bruinsma, Bote G; Uygun, Basak E; Yarmush, Martin L

    2015-02-16

    Irreversible electroporation (IRE) is an emerging, minimally invasive technique for solid tumors ablation, under clinical investigation for cancer therapy. IRE affects only the cell membrane, killing cells while preserving the extracellular matrix structure. Current reports indicate tumors recurrence rate after IRE averaging 31% of the cases, of which 10% are local recurrences. The mechanisms for these recurrences are not known and new explanations for incomplete cell death are needed. Using finite elements method for electric field distribution, we show that presence of vascular structures with blood leads to the redistribution of electric fields leading to the areas with more than 60% reduced electric field strength in proximity to large blood vessels and clustered vessel structures. In an in vivo rat model of liver IRE ablation, we show that cells located in the proximity of larger vessel structures and in proximity of clustered vessel structures appear less affected by IRE ablation than cells in the tissue parenchyma or in the proximity of small, more isolated vessels. These findings suggest a role for "electric field sinks" in local tumors recurrences after IRE and emphasize the importance of the precise mapping of the targeted organ structure and conductivity for planning of electroporation procedures.

  13. Tissue heterogeneity in structure and conductivity contribute to cell survival during irreversible electroporation ablation by “electric field sinks”

    Science.gov (United States)

    Golberg, Alexander; Bruinsma, Bote G.; Uygun, Basak E.; Yarmush, Martin L.

    2015-01-01

    Irreversible electroporation (IRE) is an emerging, minimally invasive technique for solid tumors ablation, under clinical investigation for cancer therapy. IRE affects only the cell membrane, killing cells while preserving the extracellular matrix structure. Current reports indicate tumors recurrence rate after IRE averaging 31% of the cases, of which 10% are local recurrences. The mechanisms for these recurrences are not known and new explanations for incomplete cell death are needed. Using finite elements method for electric field distribution, we show that presence of vascular structures with blood leads to the redistribution of electric fields leading to the areas with more than 60% reduced electric field strength in proximity to large blood vessels and clustered vessel structures. In an in vivo rat model of liver IRE ablation, we show that cells located in the proximity of larger vessel structures and in proximity of clustered vessel structures appear less affected by IRE ablation than cells in the tissue parenchyma or in the proximity of small, more isolated vessels. These findings suggest a role for “electric field sinks” in local tumors recurrences after IRE and emphasize the importance of the precise mapping of the targeted organ structure and conductivity for planning of electroporation procedures. PMID:25684630

  14. The Thermodynamic Continuum of Jet Engine Performance: The Principle of Lost Work due to Irreversibility in Aerospace Systems

    OpenAIRE

    Riggins, David

    2003-01-01

    The performance continuum for air-breathing engines is formally developed and illustrated in terms of fundamental thermodynamic quantities including heat and work interactions and the irreversibility occurring in the flow-path of the engine. The thermodynamically consistent base-line from which performance losses due to irreversibility must be measured is clearly defined based on this analysis. Issues and problems with conventional flow availability (flow exergy) in terms of the assessment (d...

  15. Interferon-gamma improves impaired dentinogenic and immunosuppressive functions of irreversible pulpitis-derived human dental pulp stem cells

    OpenAIRE

    Soichiro Sonoda; Haruyoshi Yamaza; Lan Ma; Yosuke Tanaka; Erika Tomoda; Reona Aijima; Kazuaki Nonaka; Toshio Kukita; Songtao Shi; Fusanori Nishimura; Takayoshi Yamaza

    2016-01-01

    Clinically, irreversible pulpitis is treated by the complete removal of pulp tissue followed by replacement with artificial materials. There is considered to be a high potential for autologous transplantation of human dental pulp stem cells (DPSCs) in endodontic treatment. The usefulness of DPSCs isolated from healthy teeth is limited. However, DPSCs isolated from diseased teeth with irreversible pulpitis (IP-DPSCs) are considered to be suitable for dentin/pulp regeneration. In this study, we...

  16. Shrinkage of thyroid volume in sunitinib-treated patients with renal-cell carcinoma: a potential marker of irreversible thyroid dysfunction?

    Science.gov (United States)

    Rogiers, Aljosja; Wolter, Pascal; Op de Beeck, Katya; Thijs, Marleen; Decallonne, Brigitte; Schöffski, Patrick

    2010-03-01

    The multitargeted tyrosine kinase inhibitor sunitinib is known to induce thyroid dysfunction in a substantial proportion of patients treated for advanced renal-cell carcinoma or gastrointestinal stromal tumors. Although sunitinib-induced hypothyroidism seems to be reversible in the majority of patients, some patients develop irreversible thyroid damage resulting in long-lasting thyroid hormone replacement therapy. We report on two cancer patients with a preexisting nodular thyroid gland, who developed thyroid dysfunction and showed marked shrinkage of the thyroid during treatment with the tyrosine kinase inhibitor, necessitating permanent thyroid hormone replacement therapy even after discontinuation of the anticancer agent. Sunitinib treatment in patients with a nodular thyroid can induce a significant decrease in the volume of the enlarged endocrine gland, associated with abnormal thyroid function tests leading to clinical hypothyroidism. The exact pathophysiology remains unknown but we discuss several possible mechanisms of sunitinib-induced thyroid shrinkage. Morphological changes of the thyroid gland can be associated with the well-described adverse biochemical effects of treatment with sunitinib and can be a potential marker of the irreversible organ damage.

  17. Optimal allocation of thermodynamic irreversibility for the integrated design of propulsion and thermal management systems

    Science.gov (United States)

    Maser, Adam Charles

    work losses over the time history of the mission. The characterization of the thermodynamic irreversibility distribution helps give the propulsion systems designer an absolute and consistent view of the tradeoffs associated with the design of the entire integrated system. Consequently, this leads directly to the question of the proper allocation of irreversibility across each of the components. The process of searching for the most favorable allocation of this irreversibility is the central theme of the research and must take into account production cost and vehicle mission performance. The production cost element is accomplished by including an engine component weight and cost prediction capability within the system model. The vehicle mission performance is obtained by directly linking the propulsion and thermal management model to a vehicle performance model and flying it through a mission profile. A canonical propulsion and thermal management systems architecture is then presented to experimentally test each element of the methodology separately: first the integrated modeling and simulation, then the irreversibility, cost, and mission performance considerations, and then finally the proper technique to perform the optimal allocation. A goal of this research is the description of the optimal allocation of system irreversibility to enable an engine cycle design with improved performance and cost at the vehicle-level. To do this, a numerical optimization was first used to minimize system-level production and operating costs by fixing the performance requirements and identifying the best settings for all of the design variables. There are two major drawbacks to this approach: It does not allow the designer to directly trade off the performance requirements and it does not allow the individual component losses to directly factor into the optimization. An irreversibility allocation approach based on the economic concept of resource allocation is then compared to the

  18. Reversible and irreversible magnetization of the Chevrel-phase superconductor PbMo6S8

    International Nuclear Information System (INIS)

    Zheng, D.N.; Ramsbottom, H.D.; Hampshire, D.P.

    1995-01-01

    Magnetic measurements have been carried out on the hot-isostatically-pressed Chevrel-phase superconductor PbMo 6 S 8 at temperatures from 4.2 K to T c and for magnetic fields up to 12 T. The results show that for the PbMo 6 S 8 compound there is a wide magnetically reversible region, between the irreversibility field B irr and the upper critical field B c2 , on the isothermal magnetic hysteresis curves. The B irr (T) line, i.e., the irreversibility line, was found to obey a power-law expression: B irr =B * (1-T/T c ) α with α∼1.5. Magnetic relaxation measurements revealed that the flux-creep effect in the material studied is substantial and is greater than those observed in conventional metallic alloys, but smaller than in high-temperature superconductors. The existence of the irreversibility line and pronounced flux-creep effect in PbMo 6 S 8 is attributed to the short coherence length of the material. From the reversible magnetization data, the values of the penetration depth, the coherence length, and the critical fields are obtained together with the Ginzburg-Landau parameter κ. At 4.2 K, the critical current density J c is 10 9 A m -2 at zero field, and decreases to 2x10 8 A m -2 at 10 T. Pinning force curves measured at different temperatures obey a Kramer-scaling law of the form: F p (=J c xB)∝b 1/2 (1-b) 2 , which indicates that the J c is limited by one predominant flux-pinning mechanism

  19. Outcome of full pulpotomy using Biodentine in adult patients with symptoms indicative of irreversible pulpitis.

    Science.gov (United States)

    Taha, N A; Abdelkhader, S Z

    2018-02-03

    To assess the outcome of full pulpotomy using Biodentine in permanent teeth with carious exposures and symptoms indicative of irreversible pulpitis. Sixty-four permanent molar teeth with symptomatic vital pulps in 52 patients aged 19-69 years were included. Preoperative pulpal and periapical diagnosis was established. After informed consent, the tooth was anaesthetized, isolated using rubber dam and disinfected with 5% NaOCl before caries excavation; subsequently, the pulp was amputated to the level of the canal orifices. Haemostasis was achieved, and a 3-mm layer of Biodentine (Septodont, Saint-Maur-des-Fosses, France) was placed as the pulpotomy agent. Resin-modified glass-ionomer liner was placed and the tooth restored with either resin composite or amalgam, and a postoperative periapical radiograph exposed. Clinical and radiographic evaluation was completed at 6 months and 1 year postoperatively. Pain levels were scored preoperatively and 2 days post-treatment. Clinical signs and symptoms indicative of irreversible pulpitis were established in all teeth, and periapical rarefaction was present in nine teeth. After 2 days, 93.8% reported complete relief of pain. At 6 months, 63 of 64 attended recall with 98.4% clinical and radiographic success. At 1 year, 59 of 63 attended recall, with 100% clinical and 98.4 radiographic success. Seven of eight cases with periapical rarefaction who attended recall had improvement in the periapical index (PAI) score. A hard tissue barrier was detected radiographically in four cases. Full pulpotomy using Biodentine was a successful treatment option for cariously exposed pulps in mature permanent molar teeth with clinical signs and symptoms indicative of irreversible pulpitis, up to 1 year. © 2018 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  20. Anaesthetic efficacy of lidocaine/clonidine for inferior alveolar nerve block in patients with irreversible pulpitis.

    Science.gov (United States)

    Shadmehr, E; Aminozarbian, M G; Akhavan, A; Mahdavian, P; Davoudi, A

    2017-06-01

    This prospective, randomized, double-blind study aimed to compare the efficacy of lidocaine with epinephrine versus lidocaine with clonidine for inferior alveolar nerve block (IANB) and hemodynamic stability (heart rate, systolic blood pressure, diastolic blood pressure and mean arterial pressure) in patients with irreversible pulpitis. One hundred patients with irreversible pulpitis in mandibular molar teeth randomly received 1.8 mL of 2% lidocaine with clonidine (15 μg mL -1 ) or 1.8 mL of 2% lidocaine with epinephrine (12.5 μg mL -1 ), using a conventional IANB technique. Endodontic access cavities were prepared 15 min after solution deposition, and all patients were required to have profound lip numbness. Success was defined as no or mild pain (visual analog scale recording) upon endodontic access cavity preparation or initial canal instrumentation. The hemodynamic parameters were measured before, during and 5, 10 and 30 min after administration. Finally, the collected data were subjected to independent t-test, chi-square and Fisher's exact test using spss software ver.20 at a significant level of 0.05. The success rates for IANB using lidocaine with epinephrine and lidocaine with clonidine solutions were 29% and 59%, respectively. The clonidine group exhibited a significantly higher success rate (P irreversible pulpitis, addition of clonidine to lidocaine improved the success rate of IANB compared to a standard lidocaine/epinephrine solution. © 2016 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  1. Histologic Findings of a Human Immature Revascularized/Regenerated Tooth with Symptomatic Irreversible Pulpitis.

    Science.gov (United States)

    Peng, Chufang; Zhao, Yuming; Wang, Wenjun; Yang, Yuan; Qin, Man; Ge, Lihong

    2017-06-01

    Pulp revascularization/regeneration in immature permanent teeth with necrotic pulp and/or apical periodontitis is an effective approach for inducing root maturation. Previous histologic studies showed cementoid/osteoid tissue and/or periodontal ligament-like tissue formed within the root canals. This case report describes the histologic findings of a human symptomatic irreversible pulpitis immature permanent tooth with most of the pulp removed after a revascularization/regeneration procedure. A human immature permanent mandibular premolar (tooth #29) was diagnosed as symptomatic irreversible pulpitis with symptomatic apical periodontitis at the emergency department. Most of the pulp was removed. The tooth was treated with revascularization/regeneration. At the 12-month recall, the radiographic examination revealed thickening of the root canal wall, narrowing of the root apex, and lengthening of the root. The tooth was extracted at 12 months for orthodontic treatment. The specimens were processed for histologic examination. Histologically, the apical third of the root canal was filled with newly formed dentinlike and pulplike tissue. There was a layer of flattened odontoblastlike cells lining the dentinal wall. In the midportion of the root canal, the newly formed dentinlike tissue gradually changed to cementumlike tissue. In the upper third of the root canal, there was a presence of cementocytelike cells housed in the lacunae of cementumlike tissue around the loose connective tissue. In the present case, regeneration of the pulplike tissue and the periodontium existed after a revascularization/regeneration procedure in an immature permanent tooth clinically diagnosed as symptomatic irreversible pulpitis. Copyright © 2017 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  2. Factors affecting the selection of a reversible or an irreversible contraceptive method in a developing country.

    Science.gov (United States)

    Ozalp, S; Yalcin, O T; Hassa, H; Erbay, B; Dalan, N

    2000-06-01

    To evaluate the factors that may affect the selection of a reversible or an irreversible contraceptive method. In an urban area of a developing country, demographic characteristics, educational and income levels, and previously used contraceptive methods were retrospectively reviewed for 3 years from the files of women who had chosen reversible or irreversible contraceptive methods. Student's t test and the chi2 test were used to analyze the data obtained from the two groups of women. Out of a total of 8078 women, 595 (7.4%) selected surgical sterilization, while 7483 (92.6%) preferred reversible methods such as intrauterine devices (38.1%), combined oral contraceptives (13.9%), condoms (40%) and Norplant (0.6%). Compared to those who preferred reversible methods, the women with surgical sterilization had a higher mean age (33.9 +/- 4.2 years versus 29.6 +/- 3.9 years), mean gravidity (3.8 +/- 0.9 versus 2.3 +/- 1.2) and mean number of living children (2.6 +/- 0.8 versus 2.1 +/- 1.1) (p < 0.01). These women had also higher rates of high-school education (37.3% versus 30.1%) and previous modern contraceptive use (78.1% versus 71.2%) (p < 0.01). None of the women with surgical sterilization, but 1770 (33.0%) of those who chose reversible methods, had fewer than two living children. These data suggest that irreversible contraceptive methods tend to be chosen by older women with higher educational levels, who have decided that their family is complete and who have at least two children.

  3. A Derivation of a Microscopic Entropy and Time Irreversibility From the Discreteness of Time

    Directory of Open Access Journals (Sweden)

    Roland Riek

    2014-06-01

    Full Text Available The basic microsopic physical laws are time reversible. In contrast, the second law of thermodynamics, which is a macroscopic physical representation of the world, is able to describe irreversible processes in an isolated system through the change of entropy ΔS > 0. It is the attempt of the present manuscript to bridge the microscopic physical world with its macrosocpic one with an alternative approach than the statistical mechanics theory of Gibbs and Boltzmann. It is proposed that time is discrete with constant step size. Its consequence is the presence of time irreversibility at the microscopic level if the present force is of complex nature (F(r ≠ const. In order to compare this discrete time irreversible mechamics (for simplicity a “classical”, single particle in a one dimensional space is selected with its classical Newton analog, time reversibility is reintroduced by scaling the time steps for any given time step n by the variable sn leading to the Nosé-Hoover Lagrangian. The corresponding Nos´e-Hoover Hamiltonian comprises a term Ndf kB T ln sn (kB the Boltzmann constant, T the temperature, and Ndf the number of degrees of freedom which is defined as the microscopic entropy Sn at time point n multiplied by T. Upon ensemble averaging this microscopic entropy Sn in equilibrium for a system which does not have fast changing forces approximates its macroscopic counterpart known from thermodynamics. The presented derivation with the resulting analogy between the ensemble averaged microscopic entropy and its thermodynamic analog suggests that the original description of the entropy by Boltzmann and Gibbs is just an ensemble averaging of the time scaling variable sn which is in equilibrium close to 1, but that the entropy

  4. Irreversible transformation of the porphyrin supramolecular structures under a water vapor environment

    International Nuclear Information System (INIS)

    Ye Ming; Zhang Yi

    2011-01-01

    Supramolecular structures formed by H 4 TPPS 4 2- have been widely used for different applications. In this paper, the stability of H 4 TPPS 4 2- nanorods on mica substrate is investigated by atom force microscopy (AFM) observation.An irreversible transformation of H 4 TPPS 4 2- from nanorods (3.8±0.4 nm in height) to a lower film structure (1.9±0.4 nm in height) was found with the samples incubated at various relative humidities (RH). The transformation rate depends strongly on the RH and environment temperature. (authors)

  5. Irreversible thermochromic behavior in gold and silver nanorod/polymeric ionic liquid nanocomposite films.

    Science.gov (United States)

    Tollan, Christopher M; Marcilla, Rebeca; Pomposo, Jose A; Rodriguez, Javier; Aizpurua, Javier; Molina, Jon; Mecerreyes, David

    2009-02-01

    The novel application of gold and silver nanorods as irreversible thermochromic dyes in polymeric ionic liquid (PIL) nanocomposites is proposed here. These materials have been synthesized by anion exchange of an imidazolium-based PIL in a solution that also contained gold nanorods. This resulted in the entrapment of the nanoobjects within a solid polymer precipitate. In this article, the effect of the temperature was studied in relation to the change of shape and, consequently, color of the gold or silver nanorods within the films. For the nanocomposites studied here, a maximum of two visual thermochromic transitions was observed for gold nanorods and up to three transitions were observed for silver nanorods.

  6. Thermodynamic restrictions on linear reversible and irreversible thermo-electro-magneto-mechanical processes

    Directory of Open Access Journals (Sweden)

    Sushma Santapuri

    2016-10-01

    In the first part of this paper, linear Thermo-Electro-Magneto-Mechanical (TEMM quasistatic processes are characterized. Thermodynamic stability conditions are further imposed on the linear constitutive model and restrictions on the corresponding material constants are derived. The framework is then extended to irreversible transport phenomena including thermoelectric, thermomagnetic and the state-of-the-art spintronic and spin caloritronic effects. Using Onsager's reciprocity relationships and the dissipation inequality, restrictions on the kinetic coefficients corresponding to charge, heat and spin transport processes are derived. All the constitutive models are accompanied by multiphysics interaction diagrams that highlight the various processes that can be characterized using this framework.

  7. Performance analysis of air-standard Diesel cycle using an alternative irreversible heat transfer approach

    International Nuclear Information System (INIS)

    Al-Hinti, I.; Akash, B.; Abu-Nada, E.; Al-Sarkhi, A.

    2008-01-01

    This study presents the investigation of air-standard Diesel cycle under irreversible heat transfer conditions. The effects of various engine parameters are presented. An alternative approach is used to evaluate net power output and cycle thermal efficiency from more realistic parameters such as air-fuel ratio, fuel mass flow rate, intake temperature, engine design parameters, etc. It is shown that for a given fuel flow rate, thermal efficiency and maximum power output increase with decreasing air-fuel ratio. Also, for a given air-fuel ratio, the maximum power output increases with increasing fuel rate. However, the effect of the thermal efficiency is limited

  8. Irreversible Thermodynamic Bound for the Efficiency of Light-Emitting Diodes

    Science.gov (United States)

    Xue, Jin; Li, Zheng; Ram, Rajeev J.

    2017-07-01

    A thermodynamic model for light-emitting diodes (LEDs) is developed by considering energy and entropy flows in the system. Thermodynamic constraints have previously been considered separately for the reversible process of electroluminescence in LEDs and for light extraction and collimation in other optical systems. By considering both processes in the LED model, an irreversible upper bound for the conversion of electrical energy to optical energy is derived and shown to be higher than unity, but tighter and more realistic than the reversible case. We also model a LED as an endoreversible heat engine where the carrier-transport processes can be directly connected to the elements of a thermodynamic cycle.

  9. ECONOMIC EFFICIENCY OF THE IMPLEMENTATION OF THE PROGRAM OF CARDIOVASCULAR DISEASES MULTIFACTORIAL PREVENTION IN THE ORGANIZED COLLECTIVE OF TECHNICAL RESEARCH INSTITUTE

    Directory of Open Access Journals (Sweden)

    A. V. Kontsevaya

    2010-01-01

    Full Text Available Aim. To estimate economic efficiency of a complex of resource-saving activities for cardiovascular diseases prevention at a workplace.Material and methods. The complex of activities including preventive examination and preventive intervention with their efficacy monitoring was performed in 523 people of a technical research institute staff. Preventive examination included evaluation procedures for cardiovascular diseases and their risk factors (89,5% of respondents. Preventive intervention based on risk factors modification was performed in intervention group. Control group included staff not participating in preventive consultation. Costs associated with cardiovascular diseases and risk factors (medical care consumption and temporary disability and cost- efficiency analysis was performed.Results. High prevalence of arterial hypertension, metabolic and psychoemotional risk factors at workplace was found in preventive examination. Significant reduction in blood pressure (BP and total cholesterol (TC plasma level as well as a tendency to cardiovascular risk (CVR decrease was reached due to preventive intervention. Costs associated with cardiovascular diseases and their risk factors in intervention group were lower than these in control group (168 584 and 489 500 rbl per 100 people yearly, respectively. Cost- efficiency analysis shown that costs of BP, TC plasma level and CVR reduction were moderate in intervention group. Costs were not efficient in control group.Conclusion. Implementation of cardiovascular diseases prevention at workplace is economically efficient both for society and for employer.

  10. Exergy analysis on the irreversibility of rotary air preheater in thermal power plant

    Energy Technology Data Exchange (ETDEWEB)

    Wang Hongyue [Division of Energy Systems, Graduate School, Ajou University, Suwon 443749 (Korea, Republic of)], E-mail: seuwhy100@ajou.ac.kr; Zhao Lingling; Zhou Qiangtai; Xu Zhigao [College of Energy and Environment, Southeast University, Nanjing 210096 (China); Kim, Hyung Taek [Division of Energy Systems, Graduate School, Ajou University, Suwon 443749 (Korea, Republic of)], E-mail: htkim@ajou.ac.kr

    2008-04-15

    Energy recovery devices can have a substantial impact on process efficiency and their relevance to the problem of conservation of energy resources is generally recognized to be beyond dispute. One type of such a device, which is commonly used in thermal power plants and air conditioning systems, is the rotary air preheater. A major disadvantage of the rotary air preheater is that there is an unavoidable leakage due to carry over and pressure difference. There are gas streams involved in the heat transfer and mixing processes. There are also irreversibilities, or exergy destruction, due to mixing, pressure losses and temperature gradients. Therefore, the purpose of this research paper is based from the second law of thermodynamics, which is to build up the relationship between the efficiency of the thermal power plant and the total process of irreversibility in the rotary air preheater using exergy analysis. For this, the effects of the variation of the principal design parameters on the rotary air preheater efficiency, the exergy efficiency, and the efficiency of the thermal power plant are examined by changing a number of parameters of rotary air preheater. Furthermore, some conclusions are reached and recommendations are made so as to give insight on designing some optimal parameters.

  11. Exergy analysis on the irreversibility of rotary air preheater in thermal power plant

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hong Yue; Kim, Hyung Taek [Division of Energy Systems, Graduate School, Ajou University, Suwon 443749 (Korea); Zhao, Ling Ling; Zhou, Qiang Tai; Xu, Zhi Gao [College of Energy and Environment, Southeast University, Nanjing 210096 (China)

    2008-04-15

    Energy recovery devices can have a substantial impact on process efficiency and their relevance to the problem of conservation of energy resources is generally recognized to be beyond dispute. One type of such a device, which is commonly used in thermal power plants and air conditioning systems, is the rotary air preheater. A major disadvantage of the rotary air preheater is that there is an unavoidable leakage due to carry over and pressure difference. There are gas streams involved in the heat transfer and mixing processes. There are also irreversibilities, or exergy destruction, due to mixing, pressure losses and temperature gradients. Therefore, the purpose of this research paper is based from the second law of thermodynamics, which is to build up the relationship between the efficiency of the thermal power plant and the total process of irreversibility in the rotary air preheater using exergy analysis. For this, the effects of the variation of the principal design parameters on the rotary air preheater efficiency, the exergy efficiency, and the efficiency of the thermal power plant are examined by changing a number of parameters of rotary air preheater. Furthermore, some conclusions are reached and recommendations are made so as to give insight on designing some optimal parameters. (author)

  12. Optimal thermoeconomic performance of an irreversible regenerative ferromagnetic Ericsson refrigeration cycle

    International Nuclear Information System (INIS)

    Xu, Zhichao; Guo, Juncheng; Lin, Guoxing; Chen, Jincan

    2016-01-01

    On the basis of the Langevin theory of classical statistical mechanics, the magnetization, entropy, and iso-field heat capacity of ferromagnetic materials are analyzed and their mathematical expressions are derived. An irreversible regenerative Ericsson refrigeration cycle by using a ferromagnetic material as the working substance is established, in which finite heat capacity rates of low and high temperature reservoirs, non-perfect regenerative heat of the refrigeration cycle, additional regenerative heat loss, etc. are taken into account. Based on the regenerative refrigeration cycle model, a thermoeconomic function is introduced as one objective function and optimized with respect to the temperatures of the working substance in the two iso-thermal processes. By means of numerical calculation, the effects of the effective factor of the heat exchangers in high/low temperature reservoir sides, efficiency of the regenerator, heat capacity rate of the low temperature reservoir, and applied magnetic field on the optimal thermoeconomic function as well as the corresponding cooling rate and coefficient of performance are revealed. The results obtained in this paper can provide some theoretical guidance for the optimal design of actual regenerative magnetic refrigerator cycle. - Highlights: • Thermodynamic performance of ferromagnetic material is analyzed. • An irreversible regenerative ferromagnetic Ericsson refrigeration cycle is set up. • The thermoeconomic objective function is introduced and optimized. • Impacts of the thermoeconomic and other parameters are discussed.

  13. Irreversibility and the Point of No Return in the Evolution of Eruptive Active Regions

    Science.gov (United States)

    Georgoulis, Manolis K.

    We combine multiple methods and findings to demonstrate that those eruptive solar active regions that form intense photospheric magnetic polarity inversion lines (PILs) enter a domain of irreversible evolution that will unavoidably force them to erupt at least once, giving rise to a major flare and an associated fast CME. Electric currents, Lorentz forces, free magnetic energy storage, and magnetic helicity, all play major roles in bringing the magnetic configuration on the verge of instability. The inferred irreversibility stems from the conservative properties of magnetic helicity in high magnetic Reynolds-number plasmas. In addition, the long-standing and fiercely debated classification of eruptive magnetic structures into sheared arcades and flux ropes is found to be of relatively little meaning: by means of the evolution above, the simplest possible sheared-arcade structure may gradually evolve into a flux rope susceptible to the helical-kink and the torus instabilities, among other destabilization mechanisms. Research partially supported by the EU Seventh Framework Programme under grant agreement No. PIRG07-GA-2010-268245 and by the European Union Social Fund (ESF) and Greek national funds through the Operational Program "Education and Lifelong Learning" of the National Strategic Reference Framework (NSRF) - Research Funding Program: Thales. Investing in knowledge society through the European Social Fund.

  14. Performance evaluation and optimization of fluidized bed boiler in ethanol plant using irreversibility analysis

    Directory of Open Access Journals (Sweden)

    Nugroho Agung Pambudi

    2017-09-01

    Full Text Available This research aims to evaluate the performance of a fluidized bed boiler in an ethanol production plant through exergy and irreversibility analysis. The study also includes the optimization of the pre-heater and the deaerator in order to improve the system efficiency. Operational data from the ethanol production plant was collected between 2015 and early 2016. The total exergy derived from the fuel was determined to be 7783 kJ/s, while the exergy efficiency of the system was found to be 26.19%, with 2214 kJ/s used in steam production, while 71.55% was lost to component irreversibility and waste heat from the pre-heater. The exergy efficiencies of individual components of the system such as the boiler, deaerator, and pre-heater were found to be 25.82%, 40.13%, and 2.617%, respectively, with the pre-heater having the lowest efficiency. Thus, the pre-heater has the highest potential to significantly improve the efficiency of the boiler system. The optimization of the pre-heater shows that a rise in temperature in the outlet of the pre-heater positively affects the exergy efficiency of the deaerator.

  15. Features of alpha-synuclein that could explain the progression and irreversibility of Parkinson's disease

    Directory of Open Access Journals (Sweden)

    Scarlet eGallegos

    2015-03-01

    Full Text Available Alpha-synuclein is a presynaptic protein expressed throughout the central nervous system, and it is the main component of Lewy bodies, one of the histopathological features of Parkinson’s disease (PD which is a progressive and irreversible neurodegenerative disorder. The conformational flexibility of α-synuclein allows it to adopt different conformations, i.e. bound to membranes or form aggregates, the oligomers are believed to be the more toxic species. In this review, we will focus on two major features of α-synuclein, transmission and toxicity that could help to understand the pathological characteristics of PD. One important feature of α-synuclein is its ability to be transmitted from neuron to neuron using mechanisms such as endocytosis, plasma membrane penetration or through exosomes, thus propagating the Lewy body pathology to different brain regions thereby contributing to the progressiveness of PD. The second feature of α-synuclein is that it confers cytotoxicity to recipient cells, principally when it is in an oligomeric state. This form causes mitochondrial dysfunction, endoplasmic reticulum stress, oxidative stress, proteasome impairment, disruption of plasma membrane and pore formation, and lead to apoptosis pathway activation and consequent cell death. The complexity of α-synuclein oligomerization and formation of toxic species could be a major factor for the irreversibility of PD and could also explain the lack of successful therapies to halt the disease.

  16. Sarcolemmal blebs and osmotic fragility as correlates of irreversible ischemic injury in preconditioned isolated rabbit cardiomyocytes.

    Science.gov (United States)

    Armstrong, S C; Shivell, L C; Ganote, C E

    2001-01-01

    The hypothesis that irreversible ischemic injury is related to sub-sarcolemmal blebbing and an inherent osmotic fragility of the blebs was tested by subjecting isolated control and ischemically preconditioned (IPC) or calyculin A (CalA)-pretreated (protected) rabbit cardiomyocytes to ischemic pelleting followed by resuspension in 340, 170 or 85 mosmol medium containing trypan blue. At time points from 0-240 min, osmotic fragility was assessed by the percentage of trypan blue permeable cells. Membrane blebs were visualized with India ink preparations. Bleb formation, following acute hypo-osmotic swelling, developed by 75 min and increased with longer periods of ischemia. Osmotic fragility developed only after 75 min. Cells resuspended in 340 mosmol media did not form blebs and largely retained the ability to exclude trypan blue, even after 240 min ischemia. Although the latent tendency for osmotic blebbing preceded the development of osmotic fragility, most osmotically fragile cells became permeable without evident sarcolemmal bleb formation. The onset of osmotic fragility was delayed in protected cells, but protection did not reduce the bleb formation. It is concluded that blebbing and osmotic fragility are independent manifestations of ischemic injury. The principal locus of irreversible ischemic injury and the protection provided by IPC may lie within the sarcolemma rather than at sarcolemmal attachments to underlying adherens junctions.

  17. Is the Supraspinatus Muscle Atrophy Truly Irreversible after Surgical Repair of Rotator Cuff Tears?

    Science.gov (United States)

    Chung, Seok Won; Kim, Sae Hoon; Tae, Suk-Kee; Yoon, Jong Pil; Choi, Jung-Ah

    2013-01-01

    Background Atrophy of rotator cuff muscles has been considered an irreversible phenomenon. The purpose of this study is to evaluate whether atrophy is truly irreversible after rotator cuff repair. Methods We measured supraspinatus muscle atrophy of 191 patients with full-thickness rotator cuff tears on preoperative magnetic resonance imaging and postoperative multidetector computed tomography images, taken at least 1 year after operation. The occupation ratio was calculated using Photoshop CS3 software. We compared the change between pre- and postoperative occupation ratios after modifying the preoperative occupation ratio. In addition, possible relationship between various clinical factors and the change of atrophy, and between the change of atrophy and cuff integrity after surgical repair were evaluated. Results The mean occupation ratio was significantly increased postoperatively from 0.44 ± 0.17 to 0.52 ± 0.17 (p < 0.001). Among 191 patients, 81 (42.4%) showed improvement of atrophy (more than a 10% increase in occupation ratio) and 33 (17.3%) worsening (more than a 10% decrease). Various clinical factors such as age tear size, or initial degree of atrophy did not affect the change of atrophy. However, the change of atrophy was related to repair integrity: cuff healing failure rate of 48.5% (16 of 33) in worsened atrophy; and 22.2% (18 of 81) in improved atrophy (p = 0.007). Conclusions The supraspinatus muscle atrophy as measured by occupation ratio could be improved postoperatively in case of successful cuff repair. PMID:23467404

  18. Time-resolved single-shot terahertz time-domain spectroscopy for ultrafast irreversible processes

    Science.gov (United States)

    Zhai, Zhao-Hui; Zhong, Sen-Cheng; Li, Jun; Zhu, Li-Guo; Meng, Kun; Li, Jiang; Liu, Qiao; Peng, Qi-Xian; Li, Ze-Ren; Zhao, Jian-Heng

    2016-09-01

    Pulsed terahertz spectroscopy is suitable for spectroscopic diagnostics of ultrafast events. However, the study of irreversible or single shot ultrafast events requires ability to record transient properties at multiple time delays, i.e., time resolved at single shot level, which is not available currently. Here by angular multiplexing use of femtosecond laser pulses, we developed and demonstrated a time resolved, transient terahertz time domain spectroscopy technique, where burst mode THz pulses were generated and then detected in a single shot measurement manner. The burst mode THz pulses contain 2 sub-THz pulses, and the time gap between them is adjustable up to 1 ns with picosecond accuracy, thus it can be used to probe the single shot event at two different time delays. The system can detect the sub-THz pulses at 0.1 THz-2.5 THz range with signal to noise ratio (SNR) of ˜400 and spectrum resolution of 0.05 THz. System design was described here, and optimizations of single shot measurement of THz pulses were discussed in detail. Methods to improve SNR were also discussed in detail. A system application was demonstrated where pulsed THz signals at different time delays of the ultrafast process were successfully acquired within single shot measurement. This time resolved transient terahertz time domain spectroscopy technique provides a new diagnostic tool for irreversible or single shot ultrafast events where dynamic information can be extracted at terahertz range within one-shot experiment.

  19. Histologic observation of a human immature permanent tooth with irreversible pulpitis after revascularization/regeneration procedure.

    Science.gov (United States)

    Shimizu, Emi; Jong, George; Partridge, Nicola; Rosenberg, Paul A; Lin, Louis M

    2012-09-01

    Histological studies of immature human permanent necrotic teeth with or without apical periodontitis after revascularization have not been reported. This case report describes the histological findings of tissue formed in the canal space of an immature permanent tooth #9 with irreversible pulpitis without apical periodontitis after revascularization. An immature human permanent tooth #9 was fractured 3.5 weeks after revascularization and could not be retained. The tooth was extracted and prepared for routine histological and immunohistochemical evaluation in order to examine the nature of tissue formed in the root canal following the revascularization procedure. At 3.5 weeks after revascularization, more than one half of the canal was filled with loose connective tissue similar to the pulp tissue. A layer of flattened odontoblast-like cells lined along the predentin. Layers of epithelial-like cells, similar to the Hertwig's epithelial root sheath, surrounded the root apex. No hard tissue was formed in the canal. Based on the histological findings in the present case, regeneration of pulp-like tissue is possible after revascularization. In this case, both the apical papilla and the Hertwig's epithelial root sheath survived in an immature permanent tooth despite irreversible pulpitis but without apical periodontitis. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  20. Irreversibility of Asymptotic Entanglement Manipulation Under Quantum Operations Completely Preserving Positivity of Partial Transpose

    Science.gov (United States)

    Wang, Xin; Duan, Runyao

    2017-11-01

    We demonstrate the irreversibility of asymptotic entanglement manipulation under quantum operations that completely preserve the positivity of partial transpose (PPT), resolving a major open problem in quantum information theory. Our key tool is a new efficiently computable additive lower bound for the asymptotic relative entropy of entanglement with respect to PPT states, which can be used to evaluate the entanglement cost under local operations and classical communication (LOCC). We find that for any rank-two mixed state supporting on the 3 ⊗3 antisymmetric subspace, the amount of distillable entanglement by PPT operations is strictly smaller than one entanglement bit (ebit) while its entanglement cost under PPT operations is exactly one ebit. As a by-product, we find that for this class of states, both the Rains's bound and its regularization are strictly less than the asymptotic relative entropy of entanglement. So, in general, there is no unique entanglement measure for the manipulation of entanglement by PPT operations. We further show a computable sufficient condition for the irreversibility of entanglement distillation by LOCC (or PPT) operations.

  1. Study of the anesthetic efficacy of inferior alveolar nerve block using articaine in irreversible pulpitis.

    Science.gov (United States)

    Ahmad, Zeeshan H; Ravikumar, H; Karale, Rupali; Preethanath, R S; Sukumaran, Anil

    2014-01-01

    The purpose of this study was to determine the anesthetic efficacy of inferior alveolar nerve block (IANB) using 4% articaine and 2% lidocaine supplemented with buccal infiltration. Forty five patients, diagnosed with irreversible pulpitis of a mandibular posterior tooth were included in the study. The first group of 15 patients received 2% lidocaine with 1:200000 epinephrine, the second group 2% lidocaine with 1: 80,000 epinephrine and the third group of 15 subjects received 4% articaine with 1:100000 epinephrine. During the access cavity preparation those patients who complained of pain received an additional buccal infiltration. The percentage of subjects who got profound anesthesia and failure to achieve anesthesia were calculated and tabulated using a visual analog scale. The results revealed that 87% of subjects who received 4% Articaine with 1:100,000 epinephrine got satisfactory anesthesia with inferior alveolar nerve block alone. Only 2 (13%) subjects received an additional buccal infiltration and none of the patients failed to obtain complete anesthesia with articaine. In comparison only 40% of subjects got complete anesthesia with 2% lidocaine with 1:200000 and 60% with 2% lidocaine with 1:80,000. It can be concluded that 4% articaine can be used effectively for obtaining profound anesthesia for endodontic procedures in patients with irreversible pulpitis.

  2. Putative Stem Cells in Human Dental Pulp with Irreversible Pulpitis-An Exploratory Study

    Science.gov (United States)

    Wang, Z.; Pan, J.; Wright, JT; Bencharit, S.; Zhang, S.; Everett, ET; Teixeira, FB; Preisser, JS

    2010-01-01

    Introduction Although human dental pulp stem cells isolated from healthy teeth have been extensively characterized, it is unknown whether stem cells also exist in clinically compromised teeth with irreversible pulpitis. Here we explored whether cells retrieved from clinically compromised dental pulp have stem cell-like properties. Methods Pulp cells were isolated from healthy teeth (control group) and from teeth with clinically diagnosed irreversible pulpitis (diseased group). Cell proliferation, stem cell marker STRO-1 expression and cell odonto-osteo-genic differentiation competence were compared. Results Cells from the diseased group demonstrated decreased colony formation capacity and a slightly decreased cell proliferation rate but had similar STRO-1 expression, and exhibited a similar percentage of positive ex vivo osteogenic induction and dentin sialophosphoprotein expression from STRO-1-enriched pulp cells. Conclusion Our study provides preliminary evidence that clinically compromised dental pulp may contain putative cells with certain stem cell properties. Further characterization of these cells will provide insight regarding whether they could serve as a source of endogenous multipotent cells in tissue regeneration based dental pulp therapy. PMID:20416426

  3. Thermally Reversible and Irreversible Phase Transition Behaviors in Poly(ethylene oxide)/Ionic Liquid Mixtures.

    Science.gov (United States)

    Chen, Yunlei; Niu, Yanhua; Gong, Pengjian; Xiao, Zhilin; Li, Guangxian

    2017-12-01

    The irreversible and reversible phase transition behaviors during phase separation-recovery (heating-cooling) cycles for poly(ethylene oxide)/1-ethyl-3-methylimidazolium tetrafluoroborate ionic liquid (PEO/[EMIM][BF 4 ]) mixtures with a lower critical solution temperature phase diagram are reported for the first time. The evident differential scanning calorimetry endothermic and exothermic peaks are observed during the heating-cooling scan cycles near the phase boundary, in which the large heat loss for samples below the critical composition (60 wt% PEO) and obvious downward shift of phase transition temperature for all the compositions between the first and second cycles are particularly attractive. After the first recovery process, a reversible behavior during the next cycles is expected. These interesting phenomena are further confirmed by optical microscopy and Fourier-transform infrared measurements. It is demonstrated that the disruption and partial recovery of the hydrogen bonds, combined with the conformational change of PEO chains, can contribute to this irreversible behavior as well as a conversion to reversible phase transition behavior. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Exergy analysis on the irreversibility of rotary air preheater in thermal power plant

    International Nuclear Information System (INIS)

    Wang Hongyue; Zhao Lingling; Zhou Qiangtai; Xu Zhigao; Kim, Hyung Taek

    2008-01-01

    Energy recovery devices can have a substantial impact on process efficiency and their relevance to the problem of conservation of energy resources is generally recognized to be beyond dispute. One type of such a device, which is commonly used in thermal power plants and air conditioning systems, is the rotary air preheater. A major disadvantage of the rotary air preheater is that there is an unavoidable leakage due to carry over and pressure difference. There are gas streams involved in the heat transfer and mixing processes. There are also irreversibilities, or exergy destruction, due to mixing, pressure losses and temperature gradients. Therefore, the purpose of this research paper is based from the second law of thermodynamics, which is to build up the relationship between the efficiency of the thermal power plant and the total process of irreversibility in the rotary air preheater using exergy analysis. For this, the effects of the variation of the principal design parameters on the rotary air preheater efficiency, the exergy efficiency, and the efficiency of the thermal power plant are examined by changing a number of parameters of rotary air preheater. Furthermore, some conclusions are reached and recommendations are made so as to give insight on designing some optimal parameters

  5. Irreversible subacute sclerotic combined degeneration of the spinal cord in a vegan subject.

    Science.gov (United States)

    Brocadello, Filippo; Levedianos, Giorgio; Piccione, Francesco; Manara, Renzo; Pesenti, Francesco Francini

    2007-01-01

    We describe a case of irreversible subacute sclerotic combined degeneration of the spinal cord in a Western vegan subject. A 57-y-old man, member of a vegan cult for 13 y, developed weakness, paraplegia, hyper-reflexia, distal symmetric muscular hypotrophy, impairment of superficial sensation in the hands and feet, loss of deep sensation in the lower limbs, and neurogenic bladder and bowel. Magnetic resonance imaging of the cervical and dorsal spine disclosed abnormally increased signal intensity on T(2)-weighted sections in the posterior and lateral columns. Subacute sclerotic combined degeneration of the spinal cord was diagnosed and treatment with cobalamin was started. Despite rehabilitative treatment, the patient developed spastic hypertonia with mild improvement of paresthesias. Six months later, vitamin B12 plasma levels and hematological analysis were normal. One year later, spastic paraplegia was still present and the patient was unable to walk despite improvement on magnetic resonance imaging. Irreversible subacute sclerotic combined degeneration of the spinal cord is a rare but possible effect of a strict vegetarian diet.

  6. Changes in gastric mucosa, submucosa, and muscularis IC pH may herald irreversible tissue injury.

    Science.gov (United States)

    Fisher, Elaine M; Chiu, Sheau Huey; LaManna, Joseph C

    2013-01-01

    Previously we noted an abrupt rise in gastric intracellular pH (IC pH) and bicarbonate buffering between 15 and 30 min of cardiac arrest which we termed agonal alkalinization, failure of pH regulation. Agonal alkalinization may represent the transition point between reversible and irreversible injury. We asked the question, what is the sequence of change in IC pH within the gastric layers, mucosa, submucosa, and muscularis, and which layer is most sensitive? This research explored changes in IC pH within the stomach layers, mucosa, submucosa, and muscularis, at 0, 5, 15, 30, and 40 min, under three conditions, normoxia (control), ischemia (cardiac arrest), and eucapnic hypoxia (12 % oxygen). The mucosa was the most alkalotic gastric layer at baseline. Ischemia and hypoxia at 40″ produced different layer responses with the mucosa and submucosa the most sensitive layers during ischemia and the muscularis during hypoxia. Further study to examine the mechanism of changes between gastric layers using spatial-temporal techniques may assist in understanding the transition to irreversible injury.

  7. Formulation and Evaluation of CTRW Governing Equations for Irreversible, Bimolecular Reactions During Transport

    Science.gov (United States)

    Hansen, S. K.; Berkowitz, B.

    2014-12-01

    The continuous time random walk (CTRW) formalism is a valuable tool for modeling both conservative and reversibly sorbing solute transport in heterogeneous porous media, underpinning both Eulerian (integrodifferential equation-based) and Lagrangian (particle tracking) approaches to transport modeling. More recently, there has been interest in modeling transport with irreversible reactions, and Lagrangian CTRW-based numerical models have been successfully applied to these problems. However, a corresponding Eulerian theory has been lacking. We recently developed Eulerian governing equations in the presence of irreversible bimolecular reactions, via the device of upscaling transport and treating reactions at a finer scale. The technique is generally valid, even in porous media that do not have an obvious division of length scales, subject to certain smoothness assumptions on the solution. We show that the governing equations we develop simplify, under appropriate circumstances, to both the generalized master equation for the unreactive CTRW and to the advection-dispersion-reaction equation. We also present a numerical corroboration of our development and its underlying smoothness assumptions obtained using a novel, indirect particle-tracking / partial differential equation hybrid technique. We discuss the implications of the new governing equations for practical reactive transport modeling and for conceptualization of subsurface processes, and highlight connections to other approaches. As applicable, we will also discuss aspects of numerical implementation.

  8. Performance optimum analysis of an irreversible molten carbonate fuel cell–Stirling heat engine hybrid system

    International Nuclear Information System (INIS)

    Chen, Liwei; Zhang, Houcheng; Gao, Songhua; Yan, Huixian

    2014-01-01

    A new hybrid system mainly consists of a molten carbonate fuel cell (MCFC) and a Stirling heat engine is established, where the Stirling heat engine is driven by the high-quality waste heat generated in the MCFC. Based on the electrochemistry and non-equilibrium thermodynamics, analytical expressions for the efficiency and power output of the hybrid system are derived by taking various irreversible losses into account. It shows that the performance of the MCFC can be greatly enhanced by coupling a Stirling heat engine to further convert the waste heat for power generation. By employing numerical calculations, not only the influences of multiple irreversible losses on the performance of the hybrid system are analyzed, but also the impacts of some operating conditions such as the operating temperature, input gas compositions and operating pressure on the performance of the hybrid system are also discussed. The investigation method in the present paper is feasible for some other similar energy conversion systems as well. - Highlights: • A model of MCFC–Stirling heat engine hybrid system is established. • Analytical expressions for the efficiency and power output are derived. • MCFC performance can be greatly enhanced by coupling a Stirling heat engine. • Effects of some operating conditions on the performance are discussed. • Optimum operation regions are subdivided by multi-objective optimization method

  9. Phenylthiomethyl Ketone-Based Fragments Show Selective and Irreversible Inhibition of Enteroviral 3C Proteases.

    Science.gov (United States)

    Schulz, Robert; Atef, Amira; Becker, Daniel; Gottschalk, Franziska; Tauber, Carolin; Wagner, Stefan; Arkona, Christoph; Abdel-Hafez, Atef A; Farag, Hassan H; Rademann, Jörg; Wolber, Gerhard

    2018-02-08

    Lead structure discovery mainly focuses on the identification of noncovalently binding ligands. Covalent linkage, however, is an essential binding mechanism for a multitude of successfully marketed drugs, although discovered by serendipity in most cases. We present a concept for the design of fragments covalently binding to proteases. Covalent linkage enables fragment binding unrelated to affinity to shallow protein binding sites and at the same time allows differentiated targeted hit verification and binding location verification through mass spectrometry. We describe a systematic and rational computational approach for the identification of covalently binding fragments from compound collections inhibiting enteroviral 3C protease, a target with high therapeutic potential. By implementing reactive groups potentially forming covalent bonds as a chemical feature in our 3D pharmacophore methodology, covalent binders were discovered by high-throughput virtual screening. We present careful experimental validation of the virtual hits using enzymatic assays and mass spectrometry unraveling a novel, previously unknown irreversible inhibition of the 3C protease by phenylthiomethyl ketone-based fragments. Subsequent synthetic optimization through fragment growing and reactivity analysis against catalytic and noncatalytic cysteines revealed specific irreversible 3C protease inhibition.

  10. Kinetics of irreversible thermal decomposition of dissociating nitrogen dioxide with nitrogen oxide or oxygen additions

    International Nuclear Information System (INIS)

    Gvozdev, A.A.

    1987-01-01

    The effect of NO or O 2 admixtures on kinetics of the irreversible thermal decomposition of nitrogen dioxide at temperatures 460-520 deg C and pressures 4-7 MPa has been studied. It follows from experimental data that the rate of N 2 O 4 formation reduces with the increase of partial pressure of oxygen or decrease of partial pressure of nitrogen oxide. The same regularity is seen for the rate of nitrogen formation. The rate constants of N 2 O formation in dissociating nitrogen tetroxide with oxygen or nitrogen oxide additions agree satisfactorily with previously published results, obtained in stoichiometric mixtures. The appreciable discrepancy at 520 deg C is bind with considerable degree of nitrogen oxide transformation which constitutes approximately 14%. It is determined that the kinetics of formation of the products of irreversible N 2 O and N 2 decomposition in stoichiometric and non-stoichiometric 2NO 2 ↔ 2NO+O 2 mixtures is described by identical 3NO → N 2 O+NO 2 and N 2 O+NO → N 2 +NO 2 reactions

  11. Choking Prevention

    Science.gov (United States)

    ... Healthy Living Healthy Living Healthy Living Nutrition Fitness Sports Oral Health Emotional Wellness Growing Healthy Sleep Safety & Prevention Safety & Prevention Safety and Prevention Immunizations At Home ...

  12. Pilot Study to Assess Safety and Clinical Outcomes of Irreversible Electroporation for Partial Gland Ablation in Men with Prostate Cancer

    Science.gov (United States)

    Murray, Katie S.; Ehdaie, Behfar; Musser, John; Mashni, Joseph; Srimathveeravalli, Govindarajan; Durack, Jeremy C.; Solomon, Stephen B.; Coleman, Jonathan A.

    2016-01-01

    Purpose Partial prostate gland ablation is a strategy to manage localized prostate cancer. Irreversible electroporation can ablate localized soft tissues. We sought to describe 30- and 90-day complications and intermediate-term functional outcomes in men undergoing prostate gland ablation using irreversible electroporation. Materials and Methods We reviewed the charts of 25 patients with prostate cancer who underwent prostate gland ablation using irreversible electroporation as a primary procedure and who were followed for at least 6 months. Results Median follow-up was 10.9 months. Grade 3 complications occurred in 2 patients including epididymitis (1) and urinary tract infection (1). Fourteen patients experienced grade ≤ 2 complications, mainly transient urinary symptoms, hematuria, and urinary tract infections. Of 25 patients, 4 (16%) had cancer in the zone of ablation on routine follow-up biopsy at 6 months. Of those with normal urinary function at baseline, 88% and 94% reported normal urinary function at 6 and 12 months after prostate gland ablation, respectively. By 12 months, only 1 patient with normal erectile function at baseline reported new difficulty with potency and only 2 patients (8%) required a pad for urinary incontinence. Conclusions Prostate gland ablation with irreversible electroporation is feasible and safe in selected men with localized prostate cancer. Intermediate-term urinary and erectile function outcomes appear reasonable. Irreversible electroporation is effective in ablation of tumor-bearing prostate tissue, as a majority of men had no evidence of residual cancer on biopsy 6 months after prostate gland ablation. PMID:27113966

  13. Anesthetic efficacy of articaine for inferior alveolar nerve blocks in patients with symptomatic versus asymptomatic irreversible pulpitis.

    Science.gov (United States)

    Argueta-Figueroa, Liliana; Arzate-Sosa, Gabriel; Mendieta-Zeron, Hugo

    2012-01-01

    This study sought to determine the anesthetic efficacy of 4% articaine with 1:100,000 epinephrine in patients with symptomatic and asymptomatic irreversible pulpitis in mandibular posterior teeth and if individual patient factors, pulpal disease characteristics, and previous medication are correlated to local anesthetic success. A second objective was to determine the specificity and sensibility of a cold test for prediction of anesthetic success prior to endodontic treatment. Seventy patients diagnosed with irreversible pulpitis in mandibular posterior teeth received 1.6 mL of 4% articaine with 1:100,000 epinephrine for an inferior alveolar nerve block (IANB) using a metal guide. The anesthetic solution was injected with a computer-preprogrammed delivery system for local anesthesia. Endodontic access was begun 15 minutes after solution deposition; later, patients rated their discomfort using the visual analog scale (VAS). The success rate for the IA NB using articaine was 64.2% in patients with symptomatic irreversible pulpitis and 86.9% in patients with asymptomatic irreversible pulpitis. Cold test prior to root canal treatment had a specificity and sensibility of 12.5% and 87.1%, respectively. The anesthetic efficacy of articaine in irreversible pulpitis is moderately acceptable, and anesthetic success increases when the patient has been premedicated with NSAIDs. The cold test appears to be a favorable indicator for predicting anesthetic success.

  14. Enhancement of a Locally Developed HIV Prevention Intervention for Hispanic/Latino MSM: A Partnership of Community-Based Organizations, a University, and the Centers for Disease Control and Prevention.

    Science.gov (United States)

    Rhodes, Scott D; Alonzo, Jorge; Mann, Lilli; Freeman, Arin; Sun, Christina J; Garcia, Manuel; Painter, Thomas M

    2015-08-01

    Hispanic/Latino men who have sex with men (MSM) in the United States are disproportionately affected by HIV and other sexually transmitted diseases (STDs); however, no efficacious behavioral HIV/STD prevention interventions are currently available for use with this vulnerable population. We describe the enhancement of HOLA en Grupos, a community-based behavioral HIV/STD prevention intervention for Spanish-speaking Hispanic/Latino MSM that is currently being implemented and evaluated in North Carolina with support from the Centers of Disease Control and Prevention (CDC). Our intervention enhancement process included incorporating local data on risks and context; identifying community needs and priorities; defining intervention core elements and key characteristics; developing a logic model; developing an intervention logo; enhancing intervention activities and materials; scripting intervention delivery; expanding the comparison intervention; and establishing a materials review committee. If the CDC-sponsored evaluation determines that HOLA en Grupos is efficacious, it will be the first such behavioral HIV/STD prevention intervention to be identified for potential use with Hispanic/Latino MSM, thereby contributing to the body of evidence-based resources that may be used for preventing HIV/STD infection among these MSM and their sex partners.

  15. Preemptive therapy prevents cytomegalovirus end-organ disease in treatment-naive patients with advanced HIV-1 infection in the HAART era.

    Directory of Open Access Journals (Sweden)

    Daisuke Mizushima

    Full Text Available BACKGROUND: The efficacy of preemptive therapy against cytomegalovirus (CMV infection remains unknown in treatment-naïve patients with advanced HIV-1 infection in the HAART era. METHODS: The subjects of this single-center observation study were 126 treatment-naïve HIV-1 infected patients with positive CMV viremia between January 1, 2000 and December 31, 2006. Inclusion criteria were age more than 17 years, CD4 count less than 100/μl, plasma CMV DNA positive, never having received antiretroviral therapy (ART and no CMV end-organ disease (EOD at first visit. The incidence of CMV-EOD was compared in patients with and without preemptive therapy against CMV-EOD. The effects of the CMV preemptive therapy were estimated in uni- and multivariate Cox hazards models. RESULTS: CMV-EOD was diagnosed in 30 of the 96 patients of the non-preemptive therapy group (31%, 230.3 per 1000 person-years, compared with 3 of the 30 patients of the preemptive therapy group (10%, 60.9 per 1000 person-years. Univariate (HR = 0.286; 95%CI, 0.087-0.939; p = 0.039 and multivariate (adjusted HR = 0.170; 95%CI, 0.049-0.602; p = 0.005 analyses confirmed that CMV-EOD is significantly prevented by CMV preemptive therapy. Multivariate analysis showed that plasma CMV DNA level correlated significantly with CMV-EOD (per log10/ml, adjusted HR = 1.941; 95%CI, 1.266-2.975; p = 0.002. Among the 30 patients on preemptive therapy, 7 (23.3% developed grade 3-4 leukopenia. The mortality rate was not significantly different between the two groups (p = 0.193, Log-rank test. CONCLUSIONS: The results indicate that preemptive therapy lowers the incidence of CMV-EOD by almost 25%. Preemptive therapy for treatment-naïve patients with CMV viremia is effective, although monitoring of potential treatment-related side effects is required.

  16. The SAT Protein of Porcine Parvovirus Accelerates Viral Spreading through Induction of Irreversible Endoplasmic Reticulum Stress.

    Science.gov (United States)

    Mészáros, István; Tóth, Renáta; Olasz, Ferenc; Tijssen, Peter; Zádori, Zoltán

    2017-08-15

    The SAT protein (SATp) of porcine parvovirus (PPV) accumulates in the endoplasmic reticulum (ER), and SAT deletion induces the slow-spreading phenotype. The in vitro comparison of the wild-type Kresse strain and its SAT knockout (SAT - ) mutant revealed that prolonged cell integrity and late viral release are responsible for the slower spreading of the SAT - virus. During PPV infection, regardless of the presence or absence of SATp, the expression of downstream ER stress response proteins (Xbp1 and CHOP) was induced. However, in the absence of SATp, significant differences in the quantity and the localization of CHOP were detected, suggesting a role of SATp in the induction of irreversible ER stress in infected cells. The involvement of the induction of irreversible ER stress in porcine testis (PT) cell necrosis and viral egress was confirmed by treatment of infected cells by ER stress-inducing chemicals (MG132, dithiothreitol, and thapsigargin), which accelerated the egress and spreading of both the wild-type and the SAT - viruses. UV stress induction had no beneficial effect on PPV infection, underscoring the specificity of ER stress pathways in the process. However, induction of CHOP and its nuclear translocation cannot alone be responsible for the biological effect of SAT, since nuclear CHOP could not complement the lack of SAT in a coexpression experiment. IMPORTANCE SATp is encoded by an alternative open reading frame of the PPV genome. Earlier we showed that SATp of the attenuated PPV NADL-2 strain accumulates in the ER and accelerates virus release and spreading. Our present work revealed that slow spreading is a general feature of SAT - PPVs and is the consequence of prolonged cell integrity. PPV infection induced ER stress in infected cells regardless of the presence of SATp, as demonstrated by the morphological changes of the ER and expression of the stress response proteins Xbp1 and CHOP. However, the presence of SATp made the ER stress more severe and

  17. Irreversible inhibition of sodium current and batrachotoxin binding by a photoaffinity-derivatized local anesthetic.

    Science.gov (United States)

    McHugh, J; Mok, W M; Wang, G K; Strichartz, G

    1995-02-01

    We have synthesized a model local anesthetic (LA), N-(2-di-N-butyl-aminoethyl)-4-azidobenzamide (DNB-AB), containing the photoactivatable aryl azido moiety, which is known to form a covalent bond to adjacent molecules when exposed to UV light (Fleet, G.W., J.R. Knowles, and R.R. Porter. 1972. Biochemical Journal. 128:499-508. Ji, T.H. 1979. Biochimica et Biophysica Acta. 559:39-69). We studied the effects of DNB-AB on the sodium current (INa) under whole-cell voltage clamp in clonal mammalian GH3 cells and on 3[H]-BTX-B binding to sheep brain synaptoneurosomes. In the absence of UV illumination, DNB-AB behaved similarly to known LAs, producing both reversible block of peak INa (IC50 = 26 microM, 20 degrees C) and reversible inhibition of 3[H]-BTX-B (50 nM in the presence of 0.12 microgram/liter Leiurus quinquestriatus scorpion venom) binding (IC50 = 3.3 microM, 37 degrees C), implying a noncovalent association between DNB-AB and its receptor(s). After exposure to UV light, both block of INa and inhibition of 3[H]-BTX-B binding were only partially reversible (INa = 42% of control; 3[H]-BTX-B binding = 23% of control) showing evidence of a light-dependent, covalent association between DNB-AB and its receptor(s). In the absence of drug, UV light had less effect on INa (post exposure INa = 96% of control) or on 3[H]-BTX-B binding (post exposure binding = 70% of control). The irreversible block of INa was partially protected by coincubation of DNB-AB with 1 mM bupivacaine (IC50 = 45 microM, for INa inhibition at 20 degrees C, Wang, G.K., and S.Y. Wang. 1992. Journal of General Physiology. 100:1003-1020), (post exposure INa = 73% of control). The irreversible inhibition of 3[H]-BTX-B binding also was partially protected by coincubation with bupivacaine (500 microM, 37 degrees C) (post exposure binding = 51% of control), suggesting that the site of irreversible inhibition of both INa and 3[H]-BTX-B binding is shared with the clinical LA bupivacaine.

  18. A statistical model for multidimensional irreversible electroporation cell death in tissue

    Directory of Open Access Journals (Sweden)

    Rubinsky Boris

    2010-02-01

    Full Text Available Abstract Background Irreversible electroporation (IRE is a minimally invasive tissue ablation technique which utilizes electric pulses delivered by electrodes to a targeted area of tissue to produce high amplitude electric fields, thus inducing irreversible damage to the cell membrane lipid bilayer. An important application of this technique is for cancer tissue ablation. Mathematical modelling is considered important in IRE treatment planning. In the past, IRE mathematical modelling used a deterministic single value for the amplitude of the electric field required for causing cell death. However, tissue, particularly cancerous tissue, is comprised of a population of different cells of different sizes and orientations, which in conventional IRE are exposed to complex electric fields; therefore, using a deterministic single value is overly simplistic. Methods We introduce and describe a new methodology for evaluating IRE induced cell death in tissue. Our approach employs a statistical Peleg-Fermi model to correlate probability of cell death in heterogeneous tissue to the parameters of electroporation pulses such as the number of pulses, electric field amplitude and pulse length. For treatment planning, the Peleg-Fermi model is combined with a numerical solution of the multidimensional electric field equation cast in a dimensionless form. This is the first time in which this concept is used for evaluating IRE cell death in multidimensional situations. Results We illustrate the methodology using data reported in literature for prostate cancer cell death by IRE. We show how to fit this data to a Fermi function in order to calculate the critical statistic parameters. To illustrate the use of the methodology, we simulated 2-D irreversible electroporation protocols and produced 2-D maps of the statistical distribution of cell death in the treated region. These plots were compared to plots produced using a deterministic model of cell death by IRE and

  19. MRI study on reversible and irreversible electroporation induced blood brain barrier disruption.

    Directory of Open Access Journals (Sweden)

    Mohammad Hjouj

    Full Text Available Electroporation, is known to induce cell membrane permeabilization in the reversible (RE mode and cell death in the irreversible (IRE mode. Using an experimental system designed to produce a continuum of IRE followed by RE around a single electrode we used MRI to study the effects of electroporation on the brain. Fifty-four rats were injected with Gd-DOTA and treated with a G25 electrode implanted 5.5 mm deep into the striata. MRI was acquired immediately after treatment, 10 min, 20 min, 30 min, and up to three weeks following the treatment using: T1W, T2W, Gradient echo (GE, serial SPGR (DCE-MRI with flip angles ranging over 5-25°, and diffusion-weighted MRI (DWMRI. Blood brain barrier (BBB disruption was depicted as clear enhancement on T1W images. The average signal intensity in the regions of T1-enhancement, representing BBB disruption, increased from 1887±83 (arbitrary units immediately post treatment to 2246±94 20 min post treatment, then reached a plateau towards the 30 min scan where it reached 2289±87. DWMRI at 30 min showed no significant effects. Early treatment effects and late irreversible damage were clearly depicted on T2W. The enhancing volume on T2W has increased by an average of 2.27±0.27 in the first 24-48 hours post treatment, suggesting an inflammatory tissue response. The permanent tissue damage, depicted as an enhancing region on T2W, 3 weeks post treatment, decreased to an average of 50±10% of the T2W enhancing volumes on the day of the treatment which was 33±5% of the BBB disruption volume. Permanent tissue damage was significantly smaller than the volume of BBB disruption, suggesting, that BBB disruption is associated with RE while tissue damage with IRE. These results demonstrate the feasibility of applying reversible and irreversible electroporation for transient BBB disruption or permanent damage, respectively, and applying MRI for planning/monitoring disruption volume/shape by optimizing electrode positions

  20. Current achievements and future perspectives in whole-organ bioengineering

    OpenAIRE

    Peloso, Andrea; Dhal, Abritee; Zambon, Joao P; Li, Peng; Orlando, Giuseppe; Atala, Anthony; Soker, Shay

    2015-01-01

    Irreversible end-stage organ failure represents one of the leading causes of death, and organ transplantation is currently the only curative solution. Donor organ shortage and adverse effects of immunosuppressive regimens are the major limiting factors for this definitive practice. Recent developments in bioengineering and regenerative medicine could provide a solid base for the future creation of implantable, bioengineered organs. Whole-organ detergent-perfusion protocols permit clinicians t...

  1. Is ‘hit and run’ a single word? The processing of irreversible binomials in neglect dyslexia

    Directory of Open Access Journals (Sweden)

    Giorgio eArcara

    2012-02-01

    Full Text Available The present study is the first neuropsychological investigation into the problem of the mental representation and processing of irreversible binomials, i.e. word pairs linked by a conjunction (e.g. ‘hit and run’, ‘dead or alive’. In order to test their lexical status, the phenomenon of neglect dyslexia is explored.People with left-sided neglect dyslexia show a clear lexical effect: they can read irreversible binomials better (i.e., by dropping the leftmost words less frequently when their components are presented in their correct order. This may be taken as an indication that they treat these constructions as lexical, not decomposable, elements. This finding therefore constitutes strong evidence that irreversible binomials tend to be stored in the mental lexicon as a whole and that this whole form is preferably addressed in the retrieval process.

  2. [Mineral trioxide aggragate pulpotomy for the treatment of immature permanent teeth with irreversible pulpitis: a preliminary clinical study].

    Science.gov (United States)

    Peng, Chufang; Zhao, Yuming; Yang, Yuan; Qin, Man

    2015-12-01

    To evaluate the preliminary clinical effect of mineral trioxide aggragate (MTA) pulpotomy on immature permanent teeth with irreversible pulpitis. Twenty-six immature permanent teeth with irreversible pulpitis were recuited from Department of Pediatric Dentistry, Peking University School and Hospital of Stomatology. These teeth were treated with partial or full pulpotomy according to the condition of pulp bleeding. MTA was used as pulp capping material. Patients were recalled periodically after the treatment. Clinical and radiographic effects were evaluated. At one year follow-up, 20 teeth were evaluated as healed or healing, 2 teeth were evaluated as failure and 4 teeth were dropped out. The success rate was considered 91% (20/22). A dentinal bridge was radiographcally observed underneath the pulpotomy site in 13 teeth(65%, 13/20). MTA pulpotomy is an effective method for the treatment of immature permanent teeth with irreversible pulpitis. But further research with longer follow up period is required.

  3. Prevention of White-Collar Crime by Knowledge and Learning in Business Organizations: An Empirical Study of Chief Financial Officer Management

    Directory of Open Access Journals (Sweden)

    Hans Solli-Soether

    2012-01-01

    Full Text Available Knowledge and learning are important in combating financial crime generallyand white-collar crime in particular. The purpose of this research is to generateinsights into prevention approaches in practice that may reflect on acontingent approach. The five hundred largest business companies in termsof annual turnover were identified in Norway for our empirical study of whitecollarcrime. A paper letter was mailed to the chief financial officer (CFOasking him or her to fill in the questionnaire to be found on a web site usinga password found in the letter. The open-ended question in the questionnaireto CFOs about prevention of white-collar crime was formulated as follows:How can white-collar crime best be prevented in your company? Survey resultsindicate an even distribution of respondents emphasizing control and respondentsemphasizing influence. This empirical research steps back from manybest practice articles and provides insights into preferences of chief financialofficers on how to prevent white-collar crime in the company.

  4. Hair repigmentation associated with the use of lenalidomide: graying may not be an irreversible process!

    Science.gov (United States)

    Dasanu, Constantin A; Mitsis, Demytra; Alexandrescu, Doru T

    2013-06-01

    We report the first case of progressive hair repigmentation associated with the use of lenalidomide in an elderly patient with multiple myeloma. The influence of lenalidomide on follicular melanogenesis may involve removing the inhibitory influences of some cytokines such as IL-1, IL-6 and TNF-α. In addition, certain endocrine effects of lenalidomide on the hypophyseal-adrenal axis could explain its action on hair pigmentation. We further hypothesize that lenalidomide may be capable of stimulating migration and/or differentiation of melanocytes to promote repigmentation of gray hair follicles. Pending the clarification of how hair repigmentation occurs with lenalidomide, our observation materializes the concept that hair graying may not be an irreversible process, which opens avenues for targeted therapeutics in the fields of cosmetics and anti-aging medicine.

  5. Exploring the optimal performances of irreversible single resonance energy selective electron refrigerators

    Science.gov (United States)

    Zhou, Junle; Chen, Lingen; Ding, Zemin; Sun, Fengrui

    2016-05-01

    Applying finite-time thermodynamics (FTT) and electronic transport theory, the optimal performances of irreversible single resonance energy selective electron (ESE) refrigerator are analyzed. The effects of heat leakage between two electron reservoirs on optimal performances are discussed. The influences of system operating parameters on cooling load, coefficient of performance (COP), figure of merit and ecological function are demonstrated using numerical examples. Comparative performance analyses among different objective functions show that performance characteristics at maximum ecological function and maximum figure of merit are of great practical significance. Combining the two optimization objectives of maximum ecological function and maximum figure of merit together, more specific optimal ranges of cooling load and COP are obtained. The results can provide some advices to the design of practical electronic machine systems.

  6. Is "hit and run" a single word? The processing of irreversible binomials in neglect dyslexia.

    Science.gov (United States)

    Arcara, Giorgio; Lacaita, Graziano; Mattaloni, Elisa; Passarini, Laura; Mondini, Sara; Benincà, Paola; Semenza, Carlo

    2012-01-01

    The present study is the first neuropsychological investigation into the problem of the mental representation and processing of irreversible binomials (IBs), i.e., word pairs linked by a conjunction (e.g., "hit and run," "dead or alive"). In order to test their lexical status, the phenomenon of neglect dyslexia is explored. People with left-sided neglect dyslexia show a clear lexical effect: they can read IBs better (i.e., by dropping the leftmost words less frequently) when their components are presented in their correct order. This may be taken as an indication that they treat these constructions as lexical, not decomposable, elements. This finding therefore constitutes strong evidence that IBs tend to be stored in the mental lexicon as a whole and that this whole form is preferably addressed in the retrieval process.

  7. Irreversible particle motion in surfactant-laden interfaces due to pressure-dependent surface viscosity

    Science.gov (United States)

    Manikantan, Harishankar; Squires, Todd M.

    2017-09-01

    The surface shear viscosity of an insoluble surfactant monolayer often depends strongly on its surface pressure. Here, we show that a particle moving within a bounded monolayer breaks the kinematic reversibility of low-Reynolds-number flows. The Lorentz reciprocal theorem allows such irreversibilities to be computed without solving the full nonlinear equations, giving the leading-order contribution of surface pressure-dependent surface viscosity. In particular, we show that a disc translating or rotating near an interfacial boundary experiences a force in the direction perpendicular to that boundary. In unbounded monolayers, coupled modes of motion can also lead to non-intuitive trajectories, which we illustrate using an interfacial analogue of the Magnus effect. This perturbative approach can be extended to more complex geometries, and to two-dimensional suspensions more generally.

  8. Graphical Analysis of PET Data Applied to Reversible and Irreversible Tracers

    Energy Technology Data Exchange (ETDEWEB)

    Logan, Jean

    1999-11-18

    Graphical analysis refers to the transformation of multiple time measurements of plasma and tissue uptake data into a linear plot, the slope of which is related to the number of available tracer binding sites. This type of analysis allows easy comparisons among experiments. No particular model structure is assumed, however it is assumed that the tracer is given by bolus injection and that both tissue uptake and the plasma concentration of unchanged tracer are monitored following tracer injection. The requirement of plasma measurements can be eliminated in some cases when a reference region is available. There are two categories of graphical methods which apply to two general types of ligands--those which bind reversibly during the scanning procedure and those which are irreversible or trapped during the time of the scanning procedure.

  9. Irreversible altering of crystalline phase of phase-change Ge-Sb thin films

    International Nuclear Information System (INIS)

    Krusin-Elbaum, L.; Shakhvorostov, D.; Cabral, C. Jr.; Raoux, S.; Jordan-Sweet, J. L.

    2010-01-01

    The stability of the crystalline phase of binary phase-change Ge x Sb 1-x films is investigated over a wide range of Ge content. From Raman spectroscopy we find the Ge-Sb crystalline structure irreversibly altered after exposure to a laser beam. We show that with increasing beam intensity/temperature Ge agglomerates and precipitates out in the amount growing with x. A simple empirical relation links Ge precipitation temperature T Ge p to the rate of change dT cryst /dx of crystallization, with the precipitation easiest on the mid-range x plateau, where T cryst is nearly constant. Our findings point to a preferable 15% < or approx. x < 50% window, that may achieve the desired cycling/archival properties of a phase-change cell.

  10. Performance analysis for minimally nonlinear irreversible refrigerators at finite cooling power

    Science.gov (United States)

    Long, Rui; Liu, Zhichun; Liu, Wei

    2018-04-01

    The coefficient of performance (COP) for general refrigerators at finite cooling power have been systematically researched through the minimally nonlinear irreversible model, and its lower and upper bounds in different operating regions have been proposed. Under the tight coupling conditions, we have calculated the universal COP bounds under the χ figure of merit in different operating regions. When the refrigerator operates in the region with lower external flux, we obtained the general bounds (0 present large values, compared to a relative small loss from the maximum cooling power. If the cooling power is the main objective, it is desirable to operate the refrigerator at a slightly lower cooling power than at the maximum one, where a small loss in the cooling power induces a much larger COP enhancement.

  11. Effects of oxymorphazone in frogs: long lasting antinociception in vivo, and apparently irreversible binding in vitro

    International Nuclear Information System (INIS)

    Benyhe, S.; Hoffman, G.; Varga, E.; Hosztafi, S.; Toth, G.; Borsodi, A.; Wollemann, M.

    1989-01-01

    Oxymorphazone was found to be a relatively weak antinociceptive drug in intact frog (Rana esculenta) when acetic acid was used as pain stimulus. Frogs remained analgesic for at least 48 hrs following oxymorphazone administration. The ligand increased the latency of wiping reflex in spinal frogs too. There effects were blocked by naloxone. In equilibrium binding studies ( 3 H)oxymorphazone had high affinity to the opioid receptors of frog brain and spinal cord as well. Kinetic experiments show that only 25% of the bound ( 3 H)oxymorphazone is readily dissociable. Preincubation of the membranes with labeled oxymorphazone results in a washing resistant inhibition of the opioid binding sites. At least 70% of the ( 3 H)oxymorphazone specific binding is apparently irreversible after reaction at 5 nM ligand concentration, and this can be enhanced by a higher concentration of tritiated ligand

  12. Strain induced irreversible critical current degradation in highly dense Bi-2212 round wire

    CERN Document Server

    Bjoerstad, R; Rikel, M.O.; Ballarino, A; Bottura, L; Jiang, J; Matras, M; Sugano, M; Hudspeth, J; Di Michiel, M

    2015-01-01

    The strain induced critical current degradation of overpressure processed straight Bi 2212/Ag wires has been studied at 77 K in self-field. For the first time superconducting properties, lattice distortions, composite wire stress and strain have been measured simultaneously in a high energy synchrotron beamline. A permanent Ic degradation of 5% occurs when the wire strain exceeds 0.60%. At a wire strain of about 0.65% a drastic n value and Ic reduction occur, and the composite stress and the Bi-2212 lattice parameter reach a plateau, indicating Bi-2212 filament fracturing. The XRD measurements show that Bi-2212 exhibits linear elastic behaviour up to the irreversible strain limit.

  13. Irreversibility line of an Ag-doped Hg-based superconductor

    International Nuclear Information System (INIS)

    Mostafa, M F; Hassen, A; Kunkel, H P

    2010-01-01

    The effect of doping with Ag of the bulk superconducting Hg 0.3 La 0.7 Ba 2 Ca 3 (Cu 1-x Ag x ) 4 O 10+δ , 0.1 ≤ x ≤ 0.3 phase (Hg-1234) is presented. The lattice parameter a = 3.824 A remains constant, while parameter c was found to increase from c = 19.0225 A (x = 0.0) to 19.08 A (x = 0.3) with the addition of Ag. The variation of T c versus the c-parameter exhibits a cupola-shaped behavior. The irreversibility line is thermally activated. The logarithmic plot of H irr versus (1 - T irr /T c (0)) shows a crossover temperature reflecting a transition from two- to three-dimensional behavior with increasing temperature. Fitting of the results to different models is discussed. Thermally activated de-pinning according to Matsushita's formula gives the best fit.

  14. Endodontic therapy of a mandibular canine tooth with irreversible pulpitis secondary to dentigerous cyst.

    Science.gov (United States)

    MacGee, Scott

    2014-01-01

    Dentigerous cysts are uncommon, yet are being reported with increasing frequency in the veterinary literature. Dentigerous cysts are a type of benign odontogenic cyst associated with impacted teeth, most commonly the mandibular first premolar tooth. Significant bone destruction can occur secondary to the expansion of a dentigerous cyst. The expanding cyst can lead to pathology of neighboring teeth, which can include external root resorption or pulpitis. Intraoral dental radiographs are imperative to properly assess the presence and extent of a dentigerous cyst, as well as the status of the neighboring teeth. This case report describes treatment for dentigerous cyst including cyst lining curettage, mandibular bone regeneration, and endodontic therapy for a canine tooth with irreversible pulpitis.

  15. Anesthetic success of supplemental infiltration in mandibular molars with irreversible pulpitis: A systematic review

    Science.gov (United States)

    Yadav, Seema

    2015-01-01

    Aim: To systematically review the anesthetic success rates of inferior alveolar nerve block (IANB) injection technique alone with that of combination of IANB and supplemental infiltration (SI) technique when used for pulpal anesthesia of mandibular posterior teeth with irreversible pulpitis during endodontic treatment. Settings and Design: The study follows a longitudinal study design involving original research. Materials and Methods: Electronic databases were systematically searched for randomized controlled clinical studies. Studies were selected by predefined inclusion and exclusion criteria. Statistical Analysis Used and Result: The statistical analysis used was based on the results of the original research. All the included studies showed that there is the difference in the values comparing the two techniques, but the data are not statistically significantly different. Conclusion: Based on this review, the better anesthetic efficacy of the SI was observed. PMID:26069400

  16. Antibiotics are not useful to reduce pain associated with irreversible pulpitis.

    Science.gov (United States)

    Hoskin, Eileen; Veitz-Keenan, Analia

    2016-09-01

    Data sourcesCochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials, MEDLINE, EMBASE, Clinical Trials.gov and the WHO International Clinical Trials Registry Platform. There were no language restrictions.Study selectionRandomised controlled trials which compared the relief of pain with systemic antibiotics and analgesics against placebo and analgesics in the preoperative phase of irreversible pulpitis. The primary interest was pain control with an antibiotic or without one in the presence of analgesics. The secondary outcomes were type, dose and frequency of medication for pain relief and any adverse effects related to hypersensitivity or other reactions to either the antibiotic or analgesics.Data extraction and synthesisTwo authors independently assessed the results of the searches. Data extraction and risk bias assessment were also carried out independently. A third reviewer settled any disagreement on inclusion. Since only one study was included a meta-analysis could not be performed.ResultsOnly one double blind randomised clinical trial involving 40 participants with a diagnosis of irreversible pulpitis in one of their teeth was included in this review. This was a low risk, well-constructed double blind study. Half of the participants were treated with penicillin 500 mg, the other with a placebo every six hours over a seven- day period. In addition, all the participants were instructed to initially take one tablet of ibuprofen every 4-6 hours as needed and to take acetaminophen with codeine (two tablets every 4-6 hours) only if the ibuprofen did not relieve the pain.There was no significant difference in the mean total number of ibuprofen tablets over the study period; 9.2(standard deviation (SD) 6.02) in the penicillin group versus, 9.6 (SD 6.34) in the placebo group; mean difference -0.40 (95% CI -4.23 to 3.43); P value = 0.84.The mean total number of Tylenol tablets, 6.9 (SD 6.87), used in the penicillin group versus 4

  17. Effects of oxymorphazone in frogs: long lasting antinociception in vivo, and apparently irreversible binding in vitro

    Energy Technology Data Exchange (ETDEWEB)

    Benyhe, S.; Hoffman, G.; Varga, E.; Hosztafi, S.; Toth, G.; Borsodi, A.; Wollemann, M.

    1989-01-01

    Oxymorphazone was found to be a relatively weak antinociceptive drug in intact frog (Rana esculenta) when acetic acid was used as pain stimulus. Frogs remained analgesic for at least 48 hrs following oxymorphazone administration. The ligand increased the latency of wiping reflex in spinal frogs too. There effects were blocked by naloxone. In equilibrium binding studies (/sup 3/H)oxymorphazone had high affinity to the opioid receptors of frog brain and spinal cord as well. Kinetic experiments show that only 25% of the bound (/sup 3/H)oxymorphazone is readily dissociable. Preincubation of the membranes with labeled oxymorphazone results in a washing resistant inhibition of the opioid binding sites. At least 70% of the (/sup 3/H)oxymorphazone specific binding is apparently irreversible after reaction at 5 nM ligand concentration, and this can be enhanced by a higher concentration of tritiated ligand.

  18. Fast X-ray microdiffraction techniques for studying irreversible transformations in materials.

    Science.gov (United States)

    Kelly, Stephen T; Trenkle, Jonathan C; Koerner, Lucas J; Barron, Sara C; Walker, Nöel; Pouliquen, Philippe O; Tate, Mark W; Gruner, Sol M; Dufresne, Eric M; Weihs, Timothy P; Hufnagel, Todd C

    2011-05-01

    A pair of techniques have been developed for performing time-resolved X-ray microdiffraction on irreversible phase transformations. In one technique capillary optics are used to focus a high-flux broad-spectrum X-ray beam to a 60 µm spot size and a fast pixel array detector is used to achieve temporal resolution of 55 µs. In the second technique the X-rays are focused with Kirkpatrick-Baez mirrors to achieve a spatial resolution better than 10 µm and a fast shutter is used to provide temporal resolution better than 20 µs while recording the diffraction pattern on a (relatively slow) X-ray CCD camera. Example data from experiments are presented where these techniques are used to study self-propagating high-temperature synthesis reactions in metal laminate foils.

  19. Irreversible Time Flow in a Two-Dimensional Dilaton Black Hole with Matter

    CERN Document Server

    Diamandis, G A; Georgalas, B C; Mavromatos, Nikolaos E; Nanopoulos, Dimitri V; Papantonopoulos, E; Ellis, John

    1998-01-01

    We show that an exact solution of two-dimensional dilaton gravity with matter discovered previously exhibits an irreversible temporal flow towards flat space with a vanishing cosmological constant. This time flow is induced by the back reaction of matter on the space-time geometry. We demonstrate that the system is not in equilibrium if the cosmological constant is non-zero, whereas the solution with zero cosmological constant is stable. The flow of the system towards this stable end-point is derived from the renormalization-group flow of the Zamolodchikov function. This behaviour is interpreted in terms of non-critical Liouville string, with the Liouville field identified as the target time.

  20. Electric fields control the orientation of peptides irreversibly immobilized on radical-functionalized surfaces.

    Science.gov (United States)

    Martin, Lewis J; Akhavan, Behnam; Bilek, Marcela M M

    2018-01-24

    Surface functionalization of an implantable device with bioactive molecules can overcome adverse biological responses by promoting specific local tissue integration. Bioactive peptides have advantages over larger protein molecules due to their robustness and sterilizability. Their relatively small size presents opportunities to control the peptide orientation on approach to a surface to achieve favourable presentation of bioactive motifs. Here we demonstrate control of the orientation of surface-bound peptides by tuning electric fields at the surface during immobilization. Guided by computational simulations, a peptide with a linear conformation in solution is designed. Electric fields are used to control the peptide approach towards a radical-functionalized surface. Spontaneous, irreversible immobilization is achieved when the peptide makes contact with the surface. Our findings show that control of both peptide orientation and surface concentration is achieved simply by varying the solution pH or by applying an electric field as delivered by a small battery.

  1. Surface and bulk modified high capacity layered oxide cathodes with low irreversible capacity loss

    Science.gov (United States)

    Manthiram, Arumugam (Inventor); Wu, Yan (Inventor)

    2010-01-01

    The present invention includes compositions, surface and bulk modifications, and methods of making of (1-x)Li[Li.sub.1/3Mn.sub.2/3]O.sub.2.xLi[Mn.sub.0.5-yNi.sub.0.5-yCo.sub.2- y]O.sub.2 cathode materials having an O3 crystal structure with a x value between 0 and 1 and y value between 0 and 0.5, reducing the irreversible capacity loss in the first cycle by surface modification with oxides and bulk modification with cationic and anionic substitutions, and increasing the reversible capacity to close to the theoretical value of insertion/extraction of one lithium per transition metal ion (250-300 mAh/g).

  2. Reversible and irreversible vascular bioeffects induced by ultrasound and microbubbles in chorioallantoic membrane model

    Science.gov (United States)

    Tarapacki, Christine; Kuebler, Wolfgang M.; Tabuchi, Arata; Karshafian, Raffi

    2017-03-01

    Background: The application of ultrasound and microbubbles at therapeutic conditions has been shown to improve delivery of molecules, cause vasoconstriction, modulate blood flow and induce a vascular shut down in in vivo cancerous tissues. The underlying mechanism has been associated with the interaction of ultrasonically-induced microbubble oscillation and cavitation with the blood vessel wall. In this study, the effect of ultrasound and microbubbles on blood flow and vascular architecture was studied using a fertilized chicken egg CAM (chorioallantoic membrane) model. Methods: CAM at day 12 of incubation (Hamburger-Hamilton stage 38-40) were exposed to ultrasound at varying acoustic pressures (160, 240 and 320 kPa peak negative pressure) in the presence of Definity microbubbles and 70 kDa FITC dextran fluorescent molecules. A volume of 50 µL Definity microbubbles were injected into a large anterior vein of the CAM prior to ultrasound exposure. The ultrasound treatment sequence consisted of 5 s exposure at 500 kHz frequency, 8 cycles and 1 kHz pulse repetition frequency with 5 s off for a total exposure of 2 minutes. Fluorescent videos and images of the CAM vasculature were acquired using intravital microscopy prior, during and following the ultrasound exposure. Perfusion was quantified by measuring the length of capillaries in a region of interest using Adobe Illustrator. Results and Discussion: The vascular bioeffects induced by USMB increased with acoustic peak negative pressure. At 160 kPa, no visible differences were observed compared to the control. At 240 kPa, a transient decrease in perfusion with subsequent recovery within 15 minutes was observed, whereas at 320 kPa, the fluorescent images showed an irreversible vascular damage. The study indicates that a potential mechanism for the transient decrease in perfusion may be related to blood coagulation. The results suggest that ultrasound and microbubbles can induce reversible and irreversible vascular

  3. A facile route for irreversible bonding of plastic-PDMS hybrid microdevices at room temperature.

    Science.gov (United States)

    Tang, Linzhi; Lee, Nae Yoon

    2010-05-21

    Plastic materials do not generally form irreversible bonds with poly(dimethylsiloxane) (PDMS) regardless of oxygen plasma treatment and a subsequent thermal process. In this paper, we perform plastic-PDMS bonding at room temperature, mediated by the formation of a chemically robust amine-epoxy bond at the interfaces. Various plastic materials, such as poly(methylmethacrylate) (PMMA), polycarbonate (PC), polyimide (PI), and poly(ethylene terephthalate) (PET) were adopted as choices for plastic materials. Irrespective of the plastic materials used, the surfaces were successfully modified with amine and epoxy functionalities, confirmed by the surface characterizations such as water contact angle measurements and X-ray photoelectron spectroscopy (XPS), and chemically robust and irreversible bonding was successfully achieved within 1 h at room temperature. The bonding strengths of PDMS with PMMA and PC sheets were measured to be 180 and 178 kPa, respectively, and their assemblies containing microchannel structures endured up to 74 and 84 psi (510 and 579 kPa) of introduced compressed air, respectively, without destroying the microdevices, representing a robust and highly stable interfacial bonding. In addition to microchannel-molded PDMS bonded with flat plastic substrates, microchannel-embossed plastics were also bonded with a flat PDMS sheet, and both types of bonded assemblies displayed sufficiently robust bonding, tolerating an intense influx of liquid whose per-minute injection volume was nearly 1000 to 2000 times higher than the total internal volume of the microchannel used. In addition to observing the bonding performance, we also investigated the potential of surface amine and epoxy functionalities as durable chemical adhesives by observing their storage-time-dependent bonding performances.

  4. Psychologic adjustment to irreversible vision loss in adults: a systematic review.

    Science.gov (United States)

    Senra, Hugo; Barbosa, Fernando; Ferreira, Patrícia; Vieira, Cristina R; Perrin, Paul B; Rogers, Heather; Rivera, Diego; Leal, Isabel

    2015-04-01

    To summarize relevant evidence investigating the psychologic adjustment to irreversible vision loss (IVL) in adults. Irreversible vision loss entails a challenging medical condition in which rehabilitation outcomes are strongly dependent on the patient's psychologic adjustment to illness and impairment. So far, no study has systematically reviewed the psychologic adjustment to IVL in adults. We reviewed all articles examining the psychologic adjustment to IVL in adults. We included articles published in English in peer-reviewed journals. We performed a keyword literature search using 4 databases (PubMed, EBSCO, Cochrane Library, and Science Direct) for all years through July 2014. We assessed risk of bias of selected studies using the RTI Item Bank for Assessing Risk of Bias and Confounding for Observational Studies of Interventions or Exposures and the Cochrane risk of bias tool for randomized controlled trials. Of a total of 3948 citations retrieved, we selected 52 eligible studies published between 1946 and 2014. The majority of studies were observational and cross-sectional in nature. Our review suggests that high levels of depression occur during the adjustment to IVL. Better adjustment to IVL was associated with greater acceptance of vision loss and use of instrumental coping, good social support, positivity, and use of assistive aids. The overall findings indicate that IVL often has negative effects on patients' quality of life and mental health and that such effects tend to remain over time. Specific factors and variables associated with the adjustment to IVL need to be clarified through further in-depth and longitudinal research. Copyright © 2015 American Academy of Ophthalmology. Published by Elsevier Inc. All rights reserved.

  5. Selective and irreversible inhibitors of aphid acetylcholinesterases: steps toward human-safe insecticides.

    Directory of Open Access Journals (Sweden)

    Yuan-Ping Pang

    Full Text Available Aphids, among the most destructive insects to world agriculture, are mainly controlled by organophosphate insecticides that disable the catalytic serine residue of acetylcholinesterase (AChE. Because these agents also affect vertebrate AChEs, they are toxic to non-target species including humans and birds. We previously reported that a cysteine residue (Cys, found at the AChE active site in aphids and other insects but not mammals, might serve as a target for insect-selective pesticides. However, aphids have two different AChEs (termed AP and AO, and only AP-AChE carries the unique Cys. The absence of the active-site Cys in AO-AChE might raise concerns about the utility of targeting that residue. Herein we report the development of a methanethiosulfonate-containing small molecule that, at 6.0 microM, irreversibly inhibits 99% of all AChE activity extracted from the greenbug aphid (Schizaphis graminum without any measurable inhibition of the human AChE. Reactivation studies using beta-mercaptoethanol confirm that the irreversible inhibition resulted from the conjugation of the inhibitor to the unique Cys. These results suggest that AO-AChE does not contribute significantly to the overall AChE activity in aphids, thus offering new insight into the relative functional importance of the two insect AChEs. More importantly, by demonstrating that the Cys-targeting inhibitor can abolish AChE activity in aphids, we can conclude that the unique Cys may be a viable target for species-selective agents to control aphids without causing human toxicity and resistance problems.

  6. Water and salt dynamics and the hydraulic conductivity feedback: irreversible soil degradation and reclamation opportunities

    Science.gov (United States)

    Mau, Yair; Porporato, Amilcare

    2017-04-01

    We present a model for the dynamics of soil water, salt concentration and exchangeable sodium fraction in the root zone, driven by irrigation water of various qualities and stochastic rainfall. The main nonlinear feedback is the decrease in hydraulic conductivity for low salinity and/or high sodicity levels. The three variables have quite disparate characteristic time scales: soil water can vary two or three orders of magnitude faster than the exchangeable sodium fraction. In certain limiting cases in which the input of water is constant, the system can be simplified by eliminating the equation for soil water, allowing a full description of the dynamics in the two-dimensional salinity-sodicity phase space. We estimate soil structure degradation time scales for high sodium-adsorption-ratio irrigation water, and delineate the regions in the salinity-sodicity phase space where sodium-induced degradation is effectively irreversible. This apparent irreversibility is the result of relatively long evolution time scales with respect to human activity. When we take into account stochastic rainfall—and the accompanying wetting and drying cycles—the system produces a myriad of statistical steady states. This means that equal environmental conditions can produce different outcomes, accessible to each other only by large interventions, such as temporary changes in the quality of irrigation water or one-time amendment use. Our characterization of the dynamics of water and salt in the root zone, and how it depends on environmental parameters, offers us opportunities to control and reclaim degraded states making optimal resource use. We show an example of sodic soil reclamation through calcium-based fertigation, with minimal time (and applied water) expenditure.

  7. Principles of the organization of social and psychological support aimed at preventing the social risks of adolescence in Russia and abroad

    Directory of Open Access Journals (Sweden)

    T.V. Tretyakova

    2014-08-01

    Full Text Available We discuss the features of development and implementation of programs of social and psychological support of adolescents in domestic and foreign practice. The priority in the field of prevention of social risks among young people is to provide systematic, comprehensive, accurate information about the consequences of substance use, adolescent training in self-care and self-regulation, the use of health-care technology, the formation of stable personal negative attitude to the problem of substance abuse. The effectiveness of preventive anti-drug programs is caused by the identification of the target group (including psychophysiological age characteristics, development of a set of preventive measures based on interagency cooperation with involvement of the minors’ parents (legal representatives.

  8. Allergy prevention.

    Science.gov (United States)

    Muche-Borowski, Cathleen; Kopp, Matthias; Reese, Imke; Sitter, Helmut; Werfel, Thomas; Schäfer, Torsten

    2010-09-01

    The further increase of allergies in industrialized countries demands evidence-based measures of primary prevention. The recommendations as published in the guideline of 2004 were updated and consented on the basis of a systematic literature search. Evidence from the period February 2003-May 2008 was searched in the electronic databases Cochrane and MEDLINE as well as in reference lists of recent reviews and by contacting experts. The retrieved citations were screened for relevance first by title and abstract and in a second step as full paper. Levels of evidence were assigned to each included study and the methodological quality of the studies was assessed as high or low. Finally the revised recommendations were formally consented (nominal group process) by representatives of relevant societies and organizations including a self-help group. Of originally 4556 hits, 217 studies (4 Cochrane Reviews, 14 meta-analyses, 19 randomized controlled trials, 135 cohort and 45 case-control studies) were included and critically appraised. Grossly unchanged remained the recommendations on avoiding environmental tobacco smoke, breast-feeding over 4 months (alternatively hypoallergenic formulas for children at risk), avoiding a mold-promoting indoor climate, vaccination according to current recommendations, and avoidance of furry pets (especially cats) in children at risk. The recommendation on reducing the house dust mite allergen exposure as a measure of primary prevention was omitted and the impact of a delayed introduction of supplementary food was reduced. New recommendations were adopted concerning fish consumption (during pregnancy / breast-feeding and as supplementary food in the first year), avoidance of overweight, and reducing the exposure to indoor and outdoor air pollutants. The revision of this guideline on a profound evidence basis led to (1) a confirmation of existing recommendations, (2) substantial revisions, and (3) new recommendations. Thereby it is possible

  9. Rape prevention

    Science.gov (United States)

    Date rape - prevention; Sexual assault - prevention ... Centers for Disease Control and Prevention website. Sexual assault and abuse and STDs. In: 2015 sexually transmitted diseases treatment guidelines 2015. www.cdc.gov/std/tg2015/sexual- ...

  10. Dengue Prevention

    Science.gov (United States)

    ... Address What's this? Submit What's this? Submit Button Prevention Recommend on Facebook Tweet Share Compartir This photograph ... medications to treat a dengue infection. This makes prevention the most important step, and prevention means avoiding ...

  11. Comparison of the oral health-related quality of life and dental pain in symptomatic irreversible pulpitis and pericoronitis

    Directory of Open Access Journals (Sweden)

    Hale Cimilli

    2012-09-01

    Conclusion: The DePaQ gives detailed information about clinical conditions related to pain and the OHRQoL status in both symptomatic irreversible pulpitis and pericoronitis. VAS scores differed between the groups according to the DePaQ items.

  12. Effect of preoperative alprazolam on the success of inferior alveolar nerve block for teeth with irreversible pulpitis.

    Science.gov (United States)

    Khademi, Abbas Ali; Saatchi, Masoud; Minaiyan, Mohsen; Rostamizadeh, Nasim; Sharafi, Fatemeh

    2012-10-01

    Success of inferior alveolar nerve (IAN) block decreases in patients with irreversible pulpitis. The purpose of this study was to evaluate the effect of preoperative administration of alprazolam on the success of the IAN block for teeth with irreversible pulpitis. Sixty patients with irreversible pulpitis of a mandibular molar were selected for this prospective, randomized, double-blind, placebo-controlled study. The patients received identical capsules of either 0.5 mg of alprazolam or placebo 45 minutes before the administration of a conventional IAN block. Access cavity preparation was initiated 15 minutes after the IAN block injection. Lip numbness was recorded for all the patients. Success was defined as no or mild pain on the basis of visual analogue scale recordings during access cavity preparation and initial instrumentation. Data were analyzed by t test, Mann-Whitney, and χ(2) tests. The success rate was 53% for alprazolam group and 40% for placebo group, with no significant difference between the 2 groups (P = .301). Within the scope of the current study, preoperative oral administration of 0.5 mg of alprazolam did not improve the success of the IAN block in mandibular molars in patients with irreversible pulpitis, and the success rate was not adequate to ensure profound pulpal anesthesia. Copyright © 2012 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  13. Disinfection procedures: their efficacy and effect on dimensional accuracy and surface quality of an irreversible hydrocolloid impression material.

    LENUS (Irish Health Repository)

    Rentzia, A

    2011-02-01

    This study investigated the antibacterial efficacy and effect of 0.55% ortho-phthalaldehyde (Cidex OPA(®)) and 0.5% sodium hypochlorite (NaOCl) on the dimensional accuracy and surface quality of gypsum casts retrieved from an irreversible hydrocolloid impression material.

  14. An Evaluation of Irreversible Psychosurgical Treatment of Patients With Obsessive-Compulsive Disorder in the Netherlands, 2001-2008

    NARCIS (Netherlands)

    van Vliet, I. M.; van Well, E. P. L.; Bruggeman, Richard; Campo, Joost A.; Hijman, R.; van Megen, H. J. G. M.; van Balkom, A. J. L. M.; van Rijen, P. C.

    Admissions for irreversible psychosurgical treatment of obsessive-compulsive disorder (OCD) by the Working Group for Indication Psychosurgery in the Netherlands were analyzed, and the postsurgical effects on symptom severity and quality of life were evaluated. The data were extracted from patient

  15. Unveiling the irreversible performance degradation of organo-inorganic halide perovskite films and solar cells during heating and cooling processes.

    Science.gov (United States)

    Mamun, Abdullah Al; Ava, Tanzila Tasnim; Byun, Hye Ryung; Jeong, Hyeon Jun; Jeong, Mun Seok; Nguyen, Loi; Gausin, Christine; Namkoong, Gon

    2017-07-26

    While organo-inorganic halide perovskite solar cells show great potential to meet future energy needs, their thermal instability raises serious questions about their commercialization viability. At present, the stability of perovskite solar cells has been studied under various environmental conditions including humidity and temperature. Nonetheless, understanding of the performance of CH 3 NH 3 PbI 3-x Cl x perovskite solar cells is limited. This study reports the irreversible performance degradation of CH 3 NH 3 PbI 3-x Cl x perovskite solar cells during the heating and cooling processes under AM 1.5 and unveils what triggers the irreversible performance degradation of solar cells. Particularly, the primary cause of the irreversible performance degradation of CH 3 NH 3 PbI 3-x Cl x is quantitatively analyzed by monitoring in real time the development of deteriorated crystallinity, charge trapping/detrapping, trap depth, and the PbI 2 phase, namely a critical signal of perovskite degradation while varying the temperature of the perovskite films and solar cells. Most surprisingly, it is revealed that the degradation of both perovskite films and solar cells was triggered at ∼70 °C. Remarkably, even after the device temperature cooled down to room temperature, the degraded performance of the solar cells persisted with increasing charge trapping and further development of the PbI 2 phase. Identification of the irreversible performance degradation of perovskite solar cells provides guidance for future development of more stable perovskite solar cells.

  16. Preliminary Diagnostic Accuracy of Multiparametric Magnetic Resonance Imaging to Detect Residual Prostate Cancer Following Focal Therapy with Irreversible Electroporation

    NARCIS (Netherlands)

    Scheltema, Matthijs J.; Chang, John I.; van den Bos, Willemien; Böhm, Maret; Delprado, Warick; Gielchinsky, Ilan; de Reijke, Theo M.; de la Rosette, Jean J.; Siriwardana, Amila R.; Shnier, Ron; Stricker, Phillip D.

    2017-01-01

    It is recommended to perform multiparametric magnetic resonance imaging (mpMRI) in the follow-up following focal therapy of prostate cancer (PCa). To determine the diagnostic accuracy of mpMRI to detect residual PCa following focal therapy with irreversible electroporation. Seventy-six patients with

  17. Thermodynamic optimisation and computational analysis of irreversibilities in a small-scale wood-fired circulating fluidised bed adiabatic combustor

    CSIR Research Space (South Africa)

    Baloyi, J

    2014-06-01

    Full Text Available An analysis of irreversibilities generated due to combustion in an adiabatic combustor burning wood was conducted. This was done for a reactant mixture varying from a rich to a lean mixture. A non-adiabatic non-premixed combustion model of a...

  18. Entransy analysis of irreversible heat pump using Newton and Dulong–Petit heat transfer laws and relations with its performance

    International Nuclear Information System (INIS)

    Açıkkalp, Emin

    2014-01-01

    Highlights: • Entransy analysis was made for irreversible heat pump. • Newton and Dulong–Petit heat transfer laws were used. • Entransy dissipations were defined and determined. • Relations between entransy and other thermodynamic parameters were determined. - Abstract: An irreversible heat pump was investigated via entransy analysis and performance criteria. In the analyses, two different convective heat transfer laws were applied to the considered system: the Newton and Dulong–Petit heat transfer laws. The irreversibilities in the system are the result of a finite heat transfer rate, a heat leak and internal irreversibilities, including friction, turbulence etc. In this study, a thermodynamic analysis was performed in detail, and the numerical solutions were used for the conducted analysis. The maximum entransy dissipation (critical points) ranges from 18436.7 kW K to 18855.3 kW K according to y for Newton’s law; however, there is no maximum point for the Dulon–Petit law. It can be concluded from this study that entransy should be used among the basic thermodynamic criteria

  19. Work hazard prevention plans

    International Nuclear Information System (INIS)

    Albertos Campos, F.

    2009-01-01

    The prevention of industrial risks is a constantly evolving discipline that has changed considerable in the last 25 years. The Cofrentes Nuclear Power Plants has always been operated with a clear policy favoring prevention by supporting the principle of its integration, i. e., that the hierarchical functional organization of the company make sure that industrial risk prevention is effective and that health and safety standards are met. The historical evolution of occupational safety in the Cofrentes Nuclear Power Plant shows a a clear trend towards improvement and is the results of many years of hard work and effort by the plants own and contractor personnel in the field of industrial risk prevention. (Author)

  20. Organization of primary prevention of infections sexually transmitted among orphans and children without parental care in the conditions of children's social institutions

    Directory of Open Access Journals (Sweden)

    K. I. Nikolaeva

    2016-01-01

    Full Text Available The article presents the results of a survey held among orphaned children and children without parental care with regard to the prevention of sexually transmitted infections as well as results showing the efficacy of awareness-raising workshops regarding reproductive health.

  1. Plague Prevention

    Science.gov (United States)

    ... Healthcare Professionals Clinicians Public Health Officials Veterinarians Prevention History of Plague Resources FAQ Prevention Recommend on Facebook Tweet Share Compartir Reduce rodent habitat around your ...

  2. Insufficient evidence to assess the effectiveness of antibiotics for irreversible pulpitis.

    Science.gov (United States)

    George, Roy

    2014-03-01

    The Cochrane Oral Health Group's Trials Register, the Cochrane Central Register of Controlled Trials (CENTRAL), Medline, Embase and the US National Institutes of Health Trials Register. Randomised controlled trials (RCTs) which compared pain relief with systemic antibiotics and analgesics, against placebo and analgesics in the acute preoperative phase of irreversible pulpitis. Study selection, risk of bias assessment and data extraction were carried out independently by two reviewers. Pooling of data was not possible and a descriptive summary is presented. One trial assessed at low risk of bias, involving 40 participants, was included in this update of the review. The quality of the body of evidence was rated low for the different outcomes. There was a close parallel distribution of the pain ratings in both the intervention and placebo groups over the seven-day study period.There was insufficient evidence to claim or refute a benefit for penicillin for pain intensity. There was no significant difference in the mean total number of ibuprofen tablets taken over the study period: 9.2 (standard deviation (SD) 6.02) in the penicillin group versus 9.6 (SD 6.34) in the placebo group; mean difference -0.40 (95% confidence interval (CI) -4.23 to 3.43; P value = 0.84). This applied equally for the mean total number of Tylenol tablets: 6.9 (SD 6.87) used in the penicillin group versus 4.45 (SD 4.82) in the placebo group; mean difference 2.45 (95% CI -1.23 to 6.13; P value = 0.19). Our secondary outcome on reporting of adverse events was not addressed in this study. This systematic, review which was based on one low-powered small sample trial assessed as a low risk of bias, illustrates that there is insufficient evidence to determine whether antibiotics reduce pain or not compared to not having antibiotics. The results of this review confirm the necessity for further larger sample and methodologically sound trials that can provide additional evidence as to whether antibiotics

  3. Loschmidt echo in many-spin systems: a quest for intrinsic decoherence and emergent irreversibility

    Science.gov (United States)

    Zangara, Pablo R.; Pastawski, Horacio M.

    2017-03-01

    If a magnetic polarization excess is locally injected in a crystal of interacting spins in thermal equilibrium, this ‘excitation’ would spread as consequence of spin-spin interactions. Such an apparently irreversible process is known as spin diffusion and it can lead the system back to ‘equilibrium’. Even so, a unitary quantum dynamics would ensure a precise memory of the non-equilibrium initial condition. Then, if at a certain time, say t/2, an experimental protocol reverses the many-body dynamics by changing the sign of the effective Hamiltonian, it would drive the system back to the initial non-equilibrium state at time t. As a matter of fact, the reversal is always perturbed by small experimental imperfections and/or uncontrolled internal or environmental degrees of freedom. This limits the amount of signal M(t) recovered locally at time t. The degradation of M(t) accounts for these perturbations, which can also be seen as the sources of decoherence. This general idea defines the Loschmidt echo (LE), which embodies the various time-reversal procedures implemented in nuclear magnetic resonance. Here, we present an invitation to the study of the LE following the pathway induced by the experiments. With such a purpose, we provide a historical and conceptual overview that briefly revisits selected phenomena that underlie the LE dynamics including chaos, decoherence, localization and equilibration. This guiding thread ultimately leads us to the discussion of decoherence and irreversibility as an emergent phenomenon. In addition, we introduce the LE formalism by means of spin-spin correlation functions in a manner suitable for presentation in a broad scope physics journal. Last, but not least, we present new results that could trigger new experiments and theoretical ideas. In particular, we propose to transform an initially localized excitation into a more complex initial state, enabling a dynamically prepared LE. This induces a global definition of the LE in

  4. Energy Efficient Operation of Distillation Columns and a Reactor Applying Irreversible Thermodynamics

    Energy Technology Data Exchange (ETDEWEB)

    Koeijer, Gelein M. de

    2002-05-01

    In this thesis the entropy production rates of diabatic distillation columns and a SO{sub 2} converter were minimised. This is the same as maximising the second law energy efficiency of the systems. The development of chemical industry can be made more sustainable by knowing this minimum. We found that the entropy production rate of distillation could be reduced up to 50 %. In order to achieve this reduction, heat exchangers were added on each tray. The characteristics of an optimum distillation column were presented. Furthermore, the entropy production rate of a SO{sub 2} converter was reduced with 16.7 % by altering the heights of catalytic beds, transfer areas of heat exchangers, and temperature differences over heat exchangers. These reductions show that there is still a large improvement potential in chemical industry. By applying the improved operations the world oil production can be reduced in the order of magnitude of 1 %. A similar reduction in the emission of the greenhouse gas CO{sub 2} can be expected. For deriving the entropy production rate in a systematic manner the theory of irreversible thermodynamics was useful. A simpler and a more complicated equation for the entropy production rate of distillation were derived. The simpler equation used only one force-flux product. It was suitable for minimisation of the entropy production rate of columns with the assumption of equilibrium between the outlets on each tray. The more complicated equation was able to describe satisfactorily the entropy production rate of an experimental column that separated the non-ideal mixture water-ethanol. It was next used to derive an extended set of transport equations for distillation, that includes the interface and the Soret effect (or thermal diffusion). Finally, irreversible thermodynamics was used to describe the contribution to the entropy production rate of heat transfer in heat exchangers. This contribution had a significant impact on the results of the

  5. Low sustainability, poor governance, and other challenges encountered by grassroots non-governmental organizations targeting HIV prevention for men who have sex with men in China - a nation-wide study.

    Science.gov (United States)

    Lau, Joseph T F; Wang, Zixin; Kim, Yoona; Li, Jinghua; Gu, Jing; Mo, Phoenix K H; Wang, Xiaodong

    2017-12-01

    Grassroots non-governmental organizations (NGOs) played pivotal roles in HIV prevention among men who have sex with men (MSM) in China. Their governance and sustainability issues were under-studied. This nation-wide study surveyed leaders of 202 of the HIV related NGOs in China.58.4% of the leaders believed that their NGO would last for ≤5 years; which was negatively associated with perceived good relationship with CDC. 65.3% mentioned ≥3 non-sustainability issues; associated factors included perceived inadequacies in prevention skills, management skills, policy support, technical support, operational support, and CDC's support; a reverse association was found for frequent collaboration with organizations in China. 30.6% of the leaders mentioned ≥7 governance issues; a stepwise model found a positive association with having no office and negative associations with number of full-time staff and core volunteers. These problems would severely limit the effectiveness of HIV prevention among MSM. Related improvements and support are warranted.

  6. Alpha 2-adrenergic receptor turnover in adipose tissue and kidney: irreversible blockade of alpha 2-adrenergic receptors by benextramine

    Energy Technology Data Exchange (ETDEWEB)

    Taouis, M.; Berlan, M.; Lafontan, M.

    1987-01-01

    The recovery of post- and extrasynaptic alpha 2-adrenergic receptor-binding sites was studied in vivo in male golden hamsters after treatment with an irreversible alpha-adrenoceptor antagonist benextramine, a tetramine disulfide that possesses a high affinity for alpha 2-binding sites. The kidney alpha 2-adrenergic receptor number was measured with (/sup 3/H)yohimbine, whereas (/sup 3/H)clonidine was used for fat cell and brain membrane alpha 2-binding site identification. Benextramine treatment of fat cell, kidney, and brain membranes reduced or completely suppressed, in an irreversible manner, (/sup 3/H) clonidine and (/sup 3/H)yohimbine binding without modifying adenosine (A1-receptor) and beta-adrenergic receptor sites. This irreversible binding was also found 1 and 2 hr after intraperitoneal administration of benextramine to the hamsters. Although it bound irreversibly to peripheral and central alpha 2-adrenergic receptors on isolated membranes, benextramine was unable to cross the blood-brain barrier of the hamster at the concentrations used (10-20 mg/kg). After the irreversible blockade, alpha 2-binding sites reappeared in kidney and adipose tissue following a monoexponential time course. Recovery of binding sites was more rapid in kidney than in adipose tissue; the half-lives of the receptor were 31 and 46 hr, respectively in the tissues. The rates of receptor production were 1.5 and 1.8 fmol/mg of protein/hr in kidney and adipose tissue. Reappearance of alpha 2-binding sites was associated with a rapid recovery of function (antilipolytic potencies of alpha 2-agonists) in fat cells inasmuch as occupancy of 15% of (/sup 3/H)clonidine-binding sites was sufficient to promote 40% inhibition of lipolysis. Benextramine is a useful tool to estimate turnover of alpha 2-adrenergic receptors under normal and pathological situations.

  7. Incidence of missed inferior alveolar nerve blocks in vital asymptomatic subjects and in patients with symptomatic irreversible pulpitis.

    Science.gov (United States)

    Fowler, Sara; Reader, Al; Beck, Mike

    2015-05-01

    The purpose of this retrospective study was to determine the incidence of missed inferior alveolar nerve (IAN) blocks by using a 1- or 2-cartridge volume of 2% lidocaine with 1:100,000 epinephrine in vital asymptomatic teeth and in emergency patients with symptomatic irreversible pulpitis. As part of 37 studies, 3169 subjects/patients were evaluated for missed IAN blocks. The study included 2450 asymptomatic subjects and 719 emergency patients presenting with symptomatic irreversible pulpitis. Each subject or patient received either a 1- or 2-cartridge volume of 2% lidocaine with 1:100,000 epinephrine. A missed block was defined as no lip numbness at 15-20 minutes after the IAN block. The effect of anesthetic volume on the incidence of missed blocks was assessed by using mixed models logistic regression with individual studies as a random effect. The incidence of missed blocks for asymptomatic subjects was 6.3% for the 1-cartridge volume and 3.8% for the 2-cartridge volume. For patients presenting with irreversible pulpitis, the incidence of missed blocks was 7.7% for the 1-cartridge volume and 2.3% for the 2-cartridge volume. In both asymptomatic subjects and patients with irreversible pulpitis, the 2-cartridge volume was significantly (P = .0395) better than the 1-cartridge volume. There were no significant effects for pulpal diagnosis (P = .7523) or the pulpal diagnosis and anesthetic volume interaction (P = .3973). Concerning missed IAN blocks, we concluded that administration of a 2-cartridge volume was significantly better (P = .0395) than a 1-cartridge volume in both asymptomatic subjects and emergency patients presenting with irreversible pulpitis. Copyright © 2015 American Association of Endodontists. Published by Elsevier Inc. All rights reserved.

  8. Enhancement of a locally developed HIV prevention intervention for Hispanic/Latino MSM: A partnership of community-based organizations, a university, and the Centers for Disease Control and Prevention

    Science.gov (United States)

    Rhodes, Scott D.; Alonzo, Jorge; Mann, Lilli; Freeman, Arin; Sun, Christina J.; Garcia, Manuel; Painter, Thomas M.

    2015-01-01

    Hispanic/Latino men who have sex with men (MSM) in the United States are disproportionately affected by HIV and other sexually transmitted diseases (STDs); however, no efficacious behavioral interventions are currently available for use with this vulnerable population. We describe the development and enhancement of HOLA en Grupos, a community-based behavioral HIV/STD prevention intervention for Spanish-speaking Hispanic/Latino MSM that is currently being implemented and evaluated. Our enhancement process included incorporating local data on risks and context; identifying community priorities; defining intervention core elements and key characteristics; developing a logic model; developing an intervention logo; enhancing intervention activities and materials; scripting intervention delivery; expanding the comparison intervention; and establishing a materials review committee. If efficacious, HOLA en Grupos will be the first behavioral intervention to be identified for potential use with Hispanic/Latino MSM, thereby contributing to the body of evidence-based resources that may be used for preventing HIV/STD infection among these MSM and their sex partners. PMID:26241382

  9. The combined effect of complex mixes of poisons on the organism of white rats in 30-day round-the-clock inhalation and measures of biological prevention

    OpenAIRE

    MIRZAKARIMOVA MALOKHAT ABDUVAKHIDOVNA

    2016-01-01

    The direction of “biological prevention” in the field of hygiene of the environment, which is understood as the complex of measures directed to the increase in resistance of individual person and population to exposure of harmful factors of the industrial and ambient environment, are increasingly being developed over the last years. For biopreventive maintenance only the means are used harmless at long application in preventive effective dosage. In this context in the industrial towns for res...

  10. Irreversible bonding of polyimide and polydimethylsiloxane (PDMS) based on a thiol-epoxy click reaction

    International Nuclear Information System (INIS)

    Hoang, Michelle V; Chung, Hyun-Joong; Elias, Anastasia L

    2016-01-01

    Polyimide is one of the most popular substrate materials for the microfabrication of flexible electronics, while polydimethylsiloxane (PDMS) is the most widely used stretchable substrate/encapsulant material. These two polymers are essential in fabricating devices for microfluidics, bioelectronics, and the internet of things; bonding these materials together is a crucial challenge. In this work, we employ click chemistry at room temperature to irreversibly bond polyimide and PDMS through thiol-epoxy bonds using two different methods. In the first method, we functionalize the surfaces of the PDMS and polyimide substrates with mercaptosilanes and epoxysilanes, respectively, for the formation of a thiol-epoxy bond in the click reaction. In the second method, we functionalize one or both surfaces with mercaptosilane and introduce an epoxy adhesive layer between the two surfaces. When the surfaces are bonded using the epoxy adhesive without any surface functionalization, an extremely small peel strength (<0.01 N mm −1 ) is measured with a peel test, and adhesive failure occurs at the PDMS surface. With surface functionalization, however, remarkably higher peel strengths of ∼0.2 N mm −1 (method 1) and  >0.3 N mm −1 (method 2) are observed, and failure occurs by tearing of the PDMS layer. We envision that the novel processing route employing click chemistry can be utilized in various cases of stretchable and flexible device fabrication. (paper)

  11. Irreversible Thermodynamic Description of Dark Matter and Radiation Creation during Inflationary Reheating

    Directory of Open Access Journals (Sweden)

    Juntong Su

    2017-01-01

    Full Text Available We investigate matter creation processes during the reheating period of the early Universe, by using the thermodynamic of open systems. The Universe is assumed to consist of the inflationary scalar field, which, through its decay, generates relativistic matter and pressureless dark matter. The inflationary scalar field transfers its energy to the newly created matter particles, with the field energy decreasing to near zero. The equations governing the irreversible matter creation are obtained by combining the thermodynamics description of the matter creation and the gravitational field equations. The role of the different inflationary scalar field potentials is analyzed by using analytical and numerical methods. The values of the energy densities of relativistic matter and dark matter reach their maximum when the Universe is reheated up to the reheating temperature, which is obtained as a function of the scalar field decay width, the scalar field particle mass, and the cosmological parameters. Particle production leads to the acceleration of the Universe during the reheating phase, with the deceleration parameter showing complex dynamics. Once the energy density of the scalar field becomes negligible with respect to the matter densities, the expansion of the Universe decelerates, and inflation has a graceful exit.

  12. Avoiding neuromuscular stimulation in liver irreversible electroporation using radiofrequency electric fields

    Science.gov (United States)

    Castellví, Quim; Mercadal, Borja; Moll, Xavier; Fondevila, Dolors; Andaluz, Anna; Ivorra, Antoni

    2018-02-01

    Electroporation-based treatments typically consist of the application of high-voltage dc pulses. As an undesired side effect, these dc pulses cause electrical stimulation of excitable tissues such as motor nerves. The present in vivo study explores the use of bursts of sinusoidal voltage in a frequency range from 50 kHz to 2 MHz, to induce irreversible electroporation (IRE) whilst avoiding neuromuscular stimulation. A series of 100 dc pulses or sinusoidal bursts, both with an individual duration of 100 µs, were delivered to rabbit liver through thin needles in a monopolar electrode configuration, and thoracic movements were recorded with an accelerometer. Tissue samples were harvested three hours after treatment and later post-processed to determine the dimensions of the IRE lesions. Thermal damage due to Joule heating was ruled out via computer simulations. Sinusoidal bursts with a frequency equal to or above 100 kHz did not cause thoracic movements and induced lesions equivalent to those obtained with conventional dc pulses when the applied voltage amplitude was sufficiently high. IRE efficacy dropped with increasing frequency. For 100 kHz bursts, it was estimated that the electric field threshold for IRE is about 1.4 kV cm-1 whereas that of dc pulses is about 0.5 kV cm-1.

  13. Irreversible Wash Aid Additive for Cesium Mitigation. Small-Scale Demonstration and Lessons Learned

    Energy Technology Data Exchange (ETDEWEB)

    Kaminski, Michael [Argonne National Lab. (ANL), Argonne, IL (United States)

    2015-01-01

    The Irreversible Wash Aid Additive process has been under development by the U.S. Environmental Protection Agency (EPA) and Argonne National Laboratory (Argonne). This process for radioactive cesium mitigation consists of a solution to wash down contaminated structures, roadways, and vehicles and a sequestering agent to bind the radionuclides from the wash water and render them environmentally immobile. The purpose of this process is to restore functionality to basic services and immediately reduce the consequences of a radiologically-contaminated urban environment. Research and development have resulted in a down-selection of technologies for integration and demonstration at the pilot-scale level as part of the Wide Area Recovery and Resiliency Program (WARRP) under the Department of Homeland Security and the Denver Urban Area Security Initiative. As part of developing the methods for performing a pilot-scale demonstration at the WARRP conference in Denver in 2012, Argonne conducted small-scale field experiments at Separmatic Systems. The main purpose of these experiments was to refine the wash water collection and separations systems and demonstrate key unit operations to help in planning for the large scale demonstration in Denver. Since the purpose of these tests was to demonstrate the operations of the system, we used no radioactive materials. After a brief set of experiments with the LAKOS unit to familiarize ourselves with its operation, two experiments were completed on two separate dates with the Separmatic systems.

  14. Irreversible electroporation ablation area enhanced by synergistic high- and low-voltage pulses.

    Directory of Open Access Journals (Sweden)

    Chenguo Yao

    Full Text Available Irreversible electroporation (IRE produced by a pulsed electric field can ablate tissue. In this study, we achieved an enhancement in ablation area by using a combination of short high-voltage pulses (HVPs to create a large electroporated area and long low-voltage pulses (LVPs to ablate the electroporated area. The experiments were conducted in potato tuber slices. Slices were ablated with an array of four pairs of parallel steel electrodes using one of the following four electric pulse protocols: HVP, LVP, synergistic HVP+LVP (SHLVP or LVP+HVP. Our results showed that the SHLVPs more effectively necrotized tissue than either the HVPs or LVPs, even when the SHLVP dose was the same as or lower than the HVP or LVP doses. The HVP and LVP order mattered and only HVPs+LVPs (SHLVPs treatments increased the size of the ablation zone because the HVPs created a large electroporated area that was more susceptible to the subsequent LVPs. Real-time temperature change monitoring confirmed that the tissue was non-thermally ablated by the electric pulses. Theoretical calculations of the synergistic effects of the SHLVPs on tissue ablation were performed. Our proposed SHLVP protocol provides options for tissue ablation and may be applied to optimize the current clinical IRE protocols.

  15. Performance analysis for an irreversible variable temperature heat reservoir closed intercooled regenerated Brayton cycle

    International Nuclear Information System (INIS)

    Wang Wenhua; Chen Lingen; Sun Fengrui; Wu Chih

    2003-01-01

    In this paper, the theory of finite time thermodynamics is used in the performance analysis of an irreversible closed intercooled regenerated Brayton cycle coupled to variable temperature heat reservoirs. The analytical formulae for dimensionless power and efficiency, as functions of the total pressure ratio, the intercooling pressure ratio, the component (regenerator, intercooler, hot and cold side heat exchangers) effectivenesses, the compressor and turbine efficiencies and the thermal capacity rates of the working fluid and the heat reservoirs, the pressure recovery coefficients, the heat reservoir inlet temperature ratio, and the cooling fluid in the intercooler and the cold side heat reservoir inlet temperature ratio, are derived. The intercooling pressure ratio is optimized for optimal power and optimal efficiency, respectively. The effects of component (regenerator, intercooler and hot and cold side heat exchangers) effectivenesses, the compressor and turbine efficiencies, the pressure recovery coefficients, the heat reservoir inlet temperature ratio and the cooling fluid in the intercooler and the cold side heat reservoir inlet temperature ratio on optimal power and its corresponding intercooling pressure ratio, as well as optimal efficiency and its corresponding intercooling pressure ratio are analyzed by detailed numerical examples. When the heat transfers between the working fluid and the heat reservoirs are executed ideally, the pressure drop losses are small enough to be neglected and the thermal capacity rates of the heat reservoirs are infinite, the results of this paper replicate those obtained in recent literature

  16. Pressure-induced irreversible metallization accompanying the phase transitions in S b2S3

    Science.gov (United States)

    Dai, Lidong; Liu, Kaixiang; Li, Heping; Wu, Lei; Hu, Haiying; Zhuang, Yukai; Yang, Linfei; Pu, Chang; Liu, Pengfei

    2018-01-01

    We have revealed S b2S3 to have two phase transitions and to undergo metallization using a diamond anvil cell at around 5.0, 15.0, and 34.0 GPa, respectively. These results were obtained on the basis of high-pressure Raman spectroscopy, temperature-dependent conductivity measurements, atomic force microscopy, high-resolution transmission electron microscopy, and first-principles calculations. The first phase transition at ˜5.0 GPa is an isostructural phase transition, which is manifested in noticeable changes in five Raman-active modes and the slope of the conductivity because of a change in the electronic structure. The second pressure-induced phase transition was characterized by a discontinuous change in the slope of conductivity and a new low-intensity Raman mode at ˜15.0 GPa . Furthermore, a semiconductor-to-metal transition was found at ˜34.0 GPa , which was accompanied by irreversible metallization, and it could be attributed to the permanently plastic deformation of the interlayer spacing. This high-pressure behavior of S b2S3 will help us to understand the universal crystal structure evolution and electrical characteristics for A2B3 -type compounds, and to facilitate their application in electronic devices.

  17. Irreversible electropermeabilization of the human pathogen Candida albicans: an in-vitro experimental study.

    Science.gov (United States)

    Novickij, Vitalij; Grainys, Audrius; Svediene, Jurgita; Markovskaja, Svetlana; Paskevicius, Algimantas; Novickij, Jurij

    2015-02-01

    Pathogenic fungi cause many life-threatening infections, especially among individuals with immune system dysfunction. The antifungal drugs commonly used to suppress fungal pathogens can result in long-lasting and toxic therapy. In this work, irreversible electropermeabilization was used to investigate the dynamics of the decrease in Candida albicans colony vitality after application of a pulsed electric field (PEF) and use of antifungal drugs. The fungi were subjected to single 250-µs to 2-ms (0.5-2.5 kV/cm) pulses or repeated short 5-µs pulses, and efficacy was compared. It was shown that electropermeabilization combined with antifungal agents results in rapid and more effective treatment, eliminating more than 90% of C. albicans colony-forming units in a single procedure, which is advantageous in biomedicine. It was also observed that, because of application of PEF and use of the antifungal agents, the Candida cells form cell aggregates and average live cell size is reduced by as much as 53%.

  18. The Effects of Irreversible Electroporation on the Colon in a Porcine Model.

    Science.gov (United States)

    Luo, Xiaomei; Liang, Xianjun; Li, Jiannan; Shi, Jian; Zhang, Wenlong; Chai, Wei; Wu, Jiuping; Guo, Shuai; Fang, Gang; Zhou, Xulong; Zhang, Jianhua; Xu, Kecheng; Zeng, Jianying; Niu, Lizhi

    2016-01-01

    Irreversible electroporation (IRE) is a method of targeted cell ablation which has been suggested as a potential cancer therapy as it leaves structures such as blood vessels and the extracellular matrix intact, thereby allowing the rapid recovery of healthy tissue. Here, we investigated the effects of IRE on the colon in vivo in a porcine model. IRE ablation was performed on the colon walls of 12 female Tibet mini-pigs, creating a total of 24 lesions. Lesions were monitored periodically by endoscopy. The pigs were euthanized 7, 14, 21 or 28 days after IRE ablation and the colons harvested for gross and histological analysis. Sections were stained with hematoxylin and eosin (H&E), Masson's trichrome (MT) stain and terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) assay. All pigs tolerated the ablation procedure without serious clinical symptoms or complications. There was no evidence of perforation by endoscopy or gross postmortem examination. All lesions were characterized by necrotic cell death with mild inflammation and hyperemia, with a sharp demarcation between ablated and adjacent normal tissue. A fibrous scar was observed in the ablated colon tissue. Histological analysis revealed damage to each layer of the colon. Histopathology findings also showed the preservation of extracellular structures and the recovery of the ablated colon. The complete ablation of the target area, its rapid recovery and the lack of posttreatment symptoms suggest that IRE ablation may be a promising therapy for tumors located adjacent to or violating the colon wall.

  19. Irreversibility of a bad start: early exposure to osmotic stress limits growth and adaptive developmental plasticity.

    Science.gov (United States)

    Wu, Chi-Shiun; Gomez-Mestre, Ivan; Kam, Yeong-Choy

    2012-05-01

    Harsh environments experienced early in development have immediate effects and potentially long-lasting consequences throughout ontogeny. We examined how salinity fluctuations affected survival, growth and development of Fejervarya limnocharis tadpoles. Specifically, we tested whether initial salinity effects on growth and rates of development were reversible and whether they affected the tadpoles' ability to adaptively accelerate development in response to deteriorating conditions later in development. Tadpoles were initially assigned to either low or high salinity, and then some were switched between salinity levels upon reaching either Gosner stage 30 (early switch) or 38 (late switch). All tadpoles initially experiencing low salinity survived whereas those initially experiencing high salinity had poor survival, even if switched to low salinity. Growth and developmental rates of tadpoles initially assigned to high salinity did not increase after osmotic stress release. Initial low salinity conditions allowed tadpoles to attain a fast pace of development even if exposed to high salinity afterwards. Tadpoles experiencing high salinity only late in development metamorphosed faster and at a smaller size, indicating an adaptive acceleration of development to avoid osmotic stress. Nonetheless, early exposure to high salinity precluded adaptive acceleration of development, always causing delayed metamorphosis relative to those in initially low salinity. Our results thus show that stressful environments experienced early in development can critically impact life history traits, having long-lasting or irreversible effects, and restricting their ability to produce adaptive plastic responses.

  20. The anthropological actions on Tandil natural landscape produced by irreversible alterations and changes in the landscape

    International Nuclear Information System (INIS)

    Bernabe, M.; Morrone, M.

    2007-01-01

    The anthropological actions on Tandil natural landscape are producing irreversible alterations and changes in the landscape. The changes take place mainly in: a) Depredation mining activity on the hills, b) Advance of the constructions on the hills. c) Superficial drainage changes by tubes and dike deficiencies) Stuffed of diggings with industrials solids remainders. The presence of System of Tandilia hills grants a high landscaping and economic value to the area. The mining activity and the related tourism constructions are in constant development. The mentioned activities are harnessed by the economic height of last five years, since Tandil is chosen as place of permanent residence by job and educational supply, and tourism by near accessibility from Buenos Aires city. Like consequence, it takes place great urban expansion where particular houses stand out, also districts, countries; and the related ones to the tourist activity like inns, that are located on the hills, generating changes in the landscape. The study area is located in the S-SW-SE sector of the city of Tandil, head of the party homonym of the Southeastern center of the province of Buenos Aires. The purpose of this paper aim to emphasize the anthropological action like main agent the natural landscape alteration, generating environmental problems. Aerial photography, and topographic maps to scale: 1:50000 were used. (author)

  1. Irreversible thermodynamics models and constitutive equations of the irradiation induced deformation and damage accumulating processes

    International Nuclear Information System (INIS)

    Wassilew, C.

    1989-11-01

    This report gives an overall evaluation of several in-reactor deformation and creep-rupture experiments performed in BR-2, FFTF, and Rapsodie on pressurised tubes of the stabilized austenitic stainless steels 1.4970, 1.4981, 1.4988, and the nickel base alloy Hastelloy-X. The irradiation induced deformation processes observed in the components operating in a neutron environment can be divided into two main groups: 1. volume conserving creep and 2. volumetric swelling. Since the observed deformation as well as damage accumulating phenomena are caused by the same constrained generated and free disposable point defects and helium atoms, it is obvious and advisable to analyze, and to model simultaneously the ensemble of the elementary mechanisms and processes effective at the same time. Phenomenological models based on the thermodynamics of irreversible processes have been developed, with the aim of: 1. grasping the partial relationships between the external variables and the response functions (creep, swelling, creep driven swelling, and time to rupture), 2. fathoming the rate-controlling mechanisms, 3. providing insight into the structural details and changes occurring during the deformation and the damage accumulating processes, 4. integrating the damage accumulating processes comprehensively, and 5. formulating the constitutive equations required to describe the elementary processes that generate plastic deformations as well as damage accumulation. (orig./MM)

  2. Irreversibility line of an Ag-doped Hg-based superconductor

    Energy Technology Data Exchange (ETDEWEB)

    Mostafa, M F [Department of Physics, Faculty of Science, University of Cairo, Giza (Egypt); Hassen, A [Department of Physics, Faculty of Science, University of Fayoum, Fayoum (Egypt); Kunkel, H P, E-mail: Mohga40@yahoo.co [Department of Physics and Astronomy, University of Manitoba, Winnipeg R3T 2N2 (Canada)

    2010-08-15

    The effect of doping with Ag of the bulk superconducting Hg{sub 0.3}La{sub 0.7}Ba{sub 2}Ca{sub 3}(Cu{sub 1-x}Ag{sub x}){sub 4}O{sub 10+{delta}}, 0.1 {<=} x {<=} 0.3 phase (Hg-1234) is presented. The lattice parameter a = 3.824 A remains constant, while parameter c was found to increase from c = 19.0225 A (x = 0.0) to 19.08 A (x = 0.3) with the addition of Ag. The variation of T{sub c} versus the c-parameter exhibits a cupola-shaped behavior. The irreversibility line is thermally activated. The logarithmic plot of H{sub irr} versus (1 - T{sub irr}/T{sub c}(0)) shows a crossover temperature reflecting a transition from two- to three-dimensional behavior with increasing temperature. Fitting of the results to different models is discussed. Thermally activated de-pinning according to Matsushita's formula gives the best fit.

  3. TRPM8 axonal expression is decreased in painful human teeth with irreversible pulpitis and cold hyperalgesia

    Science.gov (United States)

    Alvarado, Lisa T.; Perry, Griffin M.; Hargreaves, Kenneth. M.; Henry, Michael A.

    2009-01-01

    Pulpitis pain may be triggered by a cold stimulus, yet the cellular mechanisms responsible for this phenomenon are largely unknown. One possible mechanism involves the direct activation of cold-responsive thermoreceptors. The purpose of this study was to evaluate the possible role of the TRPM8 thermoreceptor in cold-mediated noxious pulpal pain mechanisms by comparing expression patterns in pulpal nerves from healthy control molars to cold-sensitive painful molars with irreversible pulpitis. Samples were identically processed with the indirect immunofluorescence method and images obtained with confocal microscopy. The immunofluorescence intensity and area occupied by TRPM8 within N52/PGP9.5 identified nerve fibers were quantified. Results showed that relative to normal samples, TRPM8 nerve area expression was significantly less in the cold-sensitive painful samples (34.9% vs. 8%, p<0.03), but with no significant difference in immunofluorescence intensity between the two groups. These results suggest that TRPM8 is most likely not involved in cold-mediated noxious pulpal pain mechanisms. PMID:17889683

  4. Irreversibility in transformation behavior of equiatomic nickel-titanium alloy by electrical resistivity measurement

    International Nuclear Information System (INIS)

    Matsumoto, Hitoshi

    2004-01-01

    Measurements of the electrical resistivity were precisely performed on shape memory Ni 50 Ti 50 alloy in order to reveal the irreversible behavior of the thermoelastic martensitic transformation with thermal cycling. The hump in the electrical resistivity during cooling is enhanced with increasing the number of complete thermal cycles to result in a peak, although no peak in the electrical resistivity is observed on the reverse transformation during heating. The electrical resistivity in the low-temperature phase, of which the temperature dependence is linear, increases with increasing the number of complete thermal cycles. The temperature coefficient of the electrical resistivity in the temperature region of the high-temperature phase increases with elevating the temperature. The transformation is strongly influenced by incomplete thermal cycles to result in a peak in the resistivity even on the reverse transformation after incomplete thermal cycling. It is thought that the anomalous behavior such as enhancement of a resistivity-peak, the increase in the electrical resistivity of the low-temperature phase, and the nonlinear relation between the resistivity and the temperature in the high-temperature phase are attributable to the appearance of an intermediate phase stabilized by transformation-induced defects, the accumulation of the transformation-induced defects, and the electron scattering due to the softening of a phonon mode in the high-temperature phase, respectively. It proved useful to make more accurate measurements of the electrical resistivity in order to investigate the intrinsic behavior of the transformation in NiTi

  5. Histological and finite element analysis of cell death due to irreversible electroporation.

    Science.gov (United States)

    Long, G; Bakos, G; Shires, P K; Gritter, L; Crissman, J W; Harris, J L; Clymer, J W

    2014-12-01

    Irreversible electroporation (IRE) has been shown to be an effective method of killing cells locally. In contrast to radiofrequency ablation, the mechanism by which cells are thought to die via IRE is the creation of pores in cell membranes, without substantial increase in tissue temperature. To determine the degree to which cell death is non-thermal, we evaluated IRE in porcine hepatocytes in vivo. Using pulse widths of 10 µs, bursts of 3 kV square-wave pulses were applied through a custom probe to the liver of an anesthetized pig. Affected tissue was evaluated histologically via stainings of hematoxylin & eosin (H&E), nitroblue tetrazolium (NBT) to monitor cell respiration and TUNEL to gauge apoptosis. Temperature was measured during the application of electroporation, and heat transfer was modeled via finite element analysis. Cell death was calculated via Arrhenius kinetics. Four distinct zones were observed within the ring return electrode; heat-fixed tissue, coagulation, necrotic, and viable. The Arrhenius damage integral estimated complete cell death only in the first zone, where the temperature exceeded 70°C, and partial or no cell death in the other zones, where maximum temperature was approximately 45°C. Except for a limited area near the electrode tip, cell death in IRE is predominantly due to a non-thermal mechanism.

  6. Irreversible damage to auditory system functions caused by perinatal hypothyroidism in rats.

    Science.gov (United States)

    Wada, Hiromi; Yumoto, Shoko; Iso, Hiroyuki

    2013-01-01

    We examined the effect of perinatal hypothyroidism on auditory function in rats using a prepulse inhibition paradigm. Pregnant rats were treated with the antithyroid drug methimazole (1-methyl-2-mercaptoimidazole) from gestational day 15 to postnatal day 21 via drinking water at concentrations (w/v) of 0 (control), 0.002 (low dose), or 0.02% (high dose). Rats from methimazole-treated mothers were tested at ages 1, 6, and 12months using techniques to examine prepulse inhibition and startle response. The startle stimulus consisted of 40ms of white noise at 115dB, whereas the prepulse, which preceded the startle stimulus by 30ms, consisted of 20ms of white noise at 75, 85, or 95dB. When the prepulse intensity was 75 or 85dB, the high-dose group showed decreased prepulse inhibition percentages compared with the control and low-dose groups. The reduced percentages of prepulse inhibition did not return to control levels over the 12-month study period. In contrast, no differences in prepulse inhibition were observed among the three dose groups when prepulse intensity was 95dB. Moreover, the high-dose group displayed excessive reaction to auditory startle stimuli compared with the other groups. Reductions in plasma free thyroxine and body weight gain were observed in the high-dose group. We conclude that perinatal hypothyroidism results in irreversible damage to auditory function in rats. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. State-resolved attosecond reversible and irreversible dynamics in strong optical fields

    Science.gov (United States)

    Sabbar, Mazyar; Timmers, Henry; Chen, Yi-Jen; Pymer, Allison K.; Loh, Zhi-Heng; Sayres, Scott G.; Pabst, Stefan; Santra, Robin; Leone, Stephen R.

    2017-02-01

    Strong-field ionization (SFI) is a key process for accessing real-time quantum dynamics of electrons on the attosecond timescale. The theoretical foundation of SFI was pioneered in the 1960s, and later refined by various analytical models. While asymptotic ionization rates predicted by these models have been tested to be in reasonable agreement for a wide range of laser parameters, predictions for SFI on the sub-laser-cycle timescale are either beyond the scope of the models or show strong qualitative deviations from full quantum-mechanical simulations. Here, using the unprecedented state specificity of attosecond transient absorption spectroscopy, we follow the real-time SFI process of the two valence spin-orbit states of xenon. The results reveal that the irreversible tunnelling contribution is accompanied by a reversible electronic population that exhibits an observable spin-orbit-dependent phase delay. A detailed theoretical analysis attributes this observation to transient ground-state polarization, an unexpected facet of SFI that cannot be captured by existing analytical models that focus exclusively on the production of asymptotic electron/ion yields.

  8. In vivo non-thermal irreversible electroporation impact on rat liver galvanic apparent internal resistance

    International Nuclear Information System (INIS)

    Golberg, A; Laufer, S; Rabinowitch, H D; Rubinsky, B

    2011-01-01

    Non-thermal irreversible electroporation (NTIRE) is a biophysical phenomenon which involves application of electric field pulses to cells or tissues, causing certain rearrangements in the membrane structure leading to cell death. The treated tissue ac impedance changes induced by electroporation were shown to be the indicators for NTIRE efficiency. In a previous study we characterized in vitro tissue galvanic apparent internal resistance (GAIR) changes due to NTIRE. Here we describe an in vivo study in which we monitored the GAIR changes of a rat liver treated by NTIRE. Electrical pulses were delivered through the same Zn/Cu electrodes by which GAIR was measured. GAIR was measured before and for 3 h after the treatment at 15 min intervals. The results were compared to the established ac bioimpedance measurement method. A decrease of 33% was measured immediately after the NTIRE treatment and a 40% decrease was measured after 3 h in GAIR values; in the same time 40% and 47% decrease respectively were measured by ac bioimpedance analyses. The temperature increase due to the NTIRE was only 0.5 deg. C. The results open the way for an inexpensive, self-powered in vivo real-time NTIRE effectiveness measurement.

  9. The Effects of Irreversible Electroporation on the Achilles Tendon: An Experimental Study in a Rabbit Model.

    Directory of Open Access Journals (Sweden)

    Yue Song

    Full Text Available To evaluate the potential effects of irreversible electroporation ablation on the Achilles tendon in a rabbit model and to compare the histopathological and biomechanical changes between specimens following electroporation ablation and radiofrequency ablation.A total of 140 six-month-old male New Zealand rabbits were used. The animals were randomly divided into two groups, 70 in the radiofrequency ablation group and 70 in the electroporation group. In situ ablations were applied directly to the Achilles tendons of rabbits using typical electroporation (1800 V/cm, 90 pulses and radiofrequency ablation (power control mode protocols. Histopathological and biomechanical evaluations were performed to examine the effects of electroporation ablation and radiofrequency ablation over time.Both electroporation and radiofrequency ablation produced complete cell ablation in the target region. Thermal damage resulted in tendon rupture 3 days post radiofrequency ablation. In contrast, electroporation-ablated Achilles tendons preserved their biomechanical properties and showed no detectable rupture at this time point. The electroporation-ablated tendons exhibited signs of recovery, including tenoblast regeneration and angiogenesis within 2 weeks, and the restoration of their integral structure was evident within 12 weeks.When applying electroporation to ablate solid tumors, major advantage could be that collateral damage to adjacent tendons or ligaments is minimized due to the unique ability of electroporation ablation to target the cell membrane. This advantage could have a significant impact on the field of tumor ablation near vital tendons or ligaments.

  10. The Effects of Irreversible Electroporation on the Achilles Tendon: An Experimental Study in a Rabbit Model.

    Science.gov (United States)

    Song, Yue; Zheng, Jingjing; Yan, Mingwei; Ding, Weidong; Xu, Kui; Fan, Qingyu; Li, Zhao

    2015-01-01

    To evaluate the potential effects of irreversible electroporation ablation on the Achilles tendon in a rabbit model and to compare the histopathological and biomechanical changes between specimens following electroporation ablation and radiofrequency ablation. A total of 140 six-month-old male New Zealand rabbits were used. The animals were randomly divided into two groups, 70 in the radiofrequency ablation group and 70 in the electroporation group. In situ ablations were applied directly to the Achilles tendons of rabbits using typical electroporation (1800 V/cm, 90 pulses) and radiofrequency ablation (power control mode) protocols. Histopathological and biomechanical evaluations were performed to examine the effects of electroporation ablation and radiofrequency ablation over time. Both electroporation and radiofrequency ablation produced complete cell ablation in the target region. Thermal damage resulted in tendon rupture 3 days post radiofrequency ablation. In contrast, electroporation-ablated Achilles tendons preserved their biomechanical properties and showed no detectable rupture at this time point. The electroporation-ablated tendons exhibited signs of recovery, including tenoblast regeneration and angiogenesis within 2 weeks, and the restoration of their integral structure was evident within 12 weeks. When applying electroporation to ablate solid tumors, major advantage could be that collateral damage to adjacent tendons or ligaments is minimized due to the unique ability of electroporation ablation to target the cell membrane. This advantage could have a significant impact on the field of tumor ablation near vital tendons or ligaments.

  11. Barthes’ Irreversible Codes: An Intertextual Reading of James Joyce’s “Araby”

    Directory of Open Access Journals (Sweden)

    Seyed Ali Booryazadeh

    2014-01-01

    Full Text Available Roland Barthes believes that semiology is the study of how language embodies the world. Semiotic codes, the paths of this embodiment, accordingly arouse his attention. Barthes in a structural analysis of Balzac’s “Sarrasine” in S/Z expounds five types and functions of these codes: proairetic (basic narrative actions; hermeneutic (narrative turning points; cultural (prior social knowledge; semic (medium-related codes and symbolic (themes. This research in a parallel manner explicates that “Araby,” one of the most widely read of James Joyce’s short stories, is abounded with two of these irreversible codes (proairetic and hermeneutic. The present study furthermore tries to show how with resort to a series of signs and the idea of intertextuality a literary text can provide probable answers for some ambiguous and questionable lexias that comprise the story’s hermeneutic code. It demonstrates that not only can the text of “Araby” be encoded by the same criteria Barthes encoded “Sarrasine” but also Joyce himself presents particular names for these codes.

  12. A Particle-Level Model of Irreversible Protein Adsorption with a Postadsorption Transition.

    Science.gov (United States)

    Van Tassel PR; Guemouri; Ramsden; Tarjus; Viot; Talbot

    1998-11-15

    Modeling the kinetics of protein adsorption at solid surfaces is needed to predict protein separations, design biosensors, and determine the body's initial response to foreign objects. We develop, at the particle level, a kinetic model that accounts geometrically for the surface blockage due to adsorption and postadsorption conformational (or orientational) transitions. Proteins are modeled as disk-shaped particles of diameter final sigmaalpha that adsorb irreversibly at random positions onto a surface at a rate kac (c is the concentration of protein in the bulk solution). Adsorption occurs only where the surface is empty. Following adsorption, a particle attempts to spread (symmetrically) to a larger diameter final sigmabeta at a rate ks. Spreading only occurs if no overlap with any previously placed particle would result. A set of equations is developed for determining the time evolution of the adsorbed protein density. These predictions are compared to new experimental data for fibronectin onto silica-titania obtained using optical waveguide lightmode spectroscopy (OWLS). We also discuss the general application of this model to experimental data. Copyright 1998 Academic Press.

  13. Irreversible thermodynamics of open chemical networks. I. Emergent cycles and broken conservation laws.

    Science.gov (United States)

    Polettini, Matteo; Esposito, Massimiliano

    2014-07-14

    In this paper and Paper II, we outline a general framework for the thermodynamic description of open chemical reaction networks, with special regard to metabolic networks regulating cellular physiology and biochemical functions. We first introduce closed networks "in a box", whose thermodynamics is subjected to strict physical constraints: the mass-action law, elementarity of processes, and detailed balance. We further digress on the role of solvents and on the seemingly unacknowledged property of network independence of free energy landscapes. We then open the system by assuming that the concentrations of certain substrate species (the chemostats) are fixed, whether because promptly regulated by the environment via contact with reservoirs, or because nearly constant in a time window. As a result, the system is driven out of equilibrium. A rich algebraic and topological structure ensues in the network of internal species: Emergent irreversible cycles are associated with nonvanishing affinities, whose symmetries are dictated by the breakage of conservation laws. These central results are resumed in the relation a + b = s(Y) between the number of fundamental affinities a, that of broken conservation laws b and the number of chemostats s(Y). We decompose the steady state entropy production rate in terms of fundamental fluxes and affinities in the spirit of Schnakenberg's theory of network thermodynamics, paving the way for the forthcoming treatment of the linear regime, of efficiency and tight coupling, of free energy transduction, and of thermodynamic constraints for network reconstruction.

  14. Evaluation of irreversible change in brain edema by T1 value

    International Nuclear Information System (INIS)

    Hoshiyama, Minoru; Motegi, Yoshimasa; Furuse, Masahiro; Izawa, Akira; Kanaoke, Yoshiki.

    1990-01-01

    Study of the time course of T 1 value was performed on 6 patients with cerebral infarction, 18 patients with cerebral hemorrhage and 21 patients with cerebral tumor. The measuring points were settled on the ischemic lesions of the cerebral infarctions and the edematous areas of the other intracranial lesions. The T 1 values were calculated from the direct spinlattice relaxation curve by FONAR QED-alpha system (static magnetic field: 433 Gauss). In the acute stage (within 7 days after stroke), more apparent prolongations of T 1 values in infarcted lesions were observed, as compared to the other edematous areas. And in the chronic stage, marked prolongations of T 1 values were recognized on infarcted lesions, often exceeding 1000 msec. From the T 1 values, the water contents of the tissues were calculated by the two state model. The water content of infarcted lesion in acute stage was 86.5%. The water contents of the other edematous areas, on the other, were all under 80%. In the prospect of prognostic values, it is our assumption that, considering that the marked prolongations of the T 1 values on the infarcted lesions are convincingly the tissue degeneration and necrosis, the boundary between the irreversible ischemic change and the edema can be prosumed in the acute stage by T 1 value of about 490 msec, i.e. the water content is about 85%. (author)

  15. Local Control of Perivascular Malignant Liver Lesions Using Percutaneous Irreversible Electroporation: Initial Experiences

    Energy Technology Data Exchange (ETDEWEB)

    Eller, Achim, E-mail: Achim.Eller@uk-erlangen.de; Schmid, Axel, E-mail: axel.schmid@uk-erlangen.de [University Hospital Erlangen, University of Erlangen-Nuremberg, Department of Radiology (Germany); Schmidt, Joachim, E-mail: joachim.schmidt@kfa.imed.uni-erlangen.de [University Hospital Erlangen, University of Erlangen-Nuremberg, Department of Anesthesiology (Germany); May, Matthias, E-mail: matthias.may@uk-erlangen.de; Brand, Michael, E-mail: michael.brand@uk-erlangen.de; Saake, Marc, E-mail: marc.saake@uk-erlangen.de; Uder, Michael, E-mail: michael.uder@uk-erlangen.de; Lell, Michael, E-mail: michael.lell@uk-erlangen.de [University Hospital Erlangen, University of Erlangen-Nuremberg, Department of Radiology (Germany)

    2015-02-15

    PurposeThis study was designed to assess efficacy and safety in the treatment of perivascular malignant liver lesions using percutaneous, computed tomography (CT)-guided irreversible electroporation (IRE).MethodsFourteen patients (mean age 58 ± 11 years) with 18 malignant liver lesions were consecutively enrolled in this study. IRE was performed in patients not eligible for surgery and lesions abutting large vessels or bile ducts. Follow-up exams were performed using multislice-CT (MS-CT) or MRI.ResultsMedium lesion diameter was 20 ± 5 mm. Ten of 14 (71 %) were successfully treated with no local recurrence to date (mean follow-up 388 ± 160 days). One case left initial tumor control unclear and additional RFA was performed 4 weeks after IRE. Complications occurred in 4 of 14 (29 %) cases. In one case, intervention was terminated and abdominal bleeding required laparotomy. In two cases, a postinterventional hematothorax required intervention. In another case, abdominal bleeding could be managed conservatively. No complications related to the bile ducts occurred.ConclusionsPercutaneous IRE seems to be effective in perivascular lesions but is associated with a higher complication rate compared with thermoablative techniques.

  16. Interplay of Determinism and Randomness: From Irreversibility to Chaos, Fractals, and Stochasticity

    Science.gov (United States)

    Tsonis, A.

    2017-12-01

    We will start our discussion into randomness by looking exclusively at our formal mathematical system to show that even in this pure and strictly logical system one cannot do away with randomness. By employing simple mathematical models, we will identify the three possible sources of randomness: randomness due to inability to find the rules (irreversibility), randomness due to inability to have infinite power (chaos), and randomness due to stochastic processes. Subsequently we will move from the mathematical system to our physical world to show that randomness, through the quantum mechanical character of small scales, through chaos, and because of the second law of thermodynamics, is an intrinsic property of nature as well. We will subsequently argue that the randomness in the physical world is consistent with the three sources of randomness suggested from the study of simple mathematical systems. Many examples ranging from purely mathematical to natural processes will be presented, which clearly demonstrate how the combination of rules and randomness produces the world we live in. Finally, the principle of least effort or the principle of minimum energy consumption will be suggested as the underlying principle behind this symbiosis between determinism and randomness.

  17. Irreversible muscle damage in bodybuilding due to long-term intramuscular oil injection.

    Science.gov (United States)

    Banke, I J; Prodinger, P M; Waldt, S; Weirich, G; Holzapfel, B M; Gradinger, R; Rechl, H

    2012-10-01

    Intramuscular oil injections generating slowly degrading oil-based depots represent a controversial subject in bodybuilding and fitness. However they seem to be commonly reported in a large number of non-medical reports, movies and application protocols for 'site-injections'. Surprisingly the impact of long-term (ab)use on the musculature as well as potential side-effects compromising health and sports ability are lacking in the medical literature. We present the case of a 40 year old male semi-professional bodybuilder with systemic infection and painful reddened swellings of the right upper arm forcing him to discontinue weightlifting. Over the last 8 years he daily self-injected sterilized sesame seed oil at numerous intramuscular locations for the purpose of massive muscle building. Whole body MRI showed more than 100 intramuscular rather than subcutaneous oil cysts and loss of normal muscle anatomy. 2-step septic surgery of the right upper arm revealed pus-filled cystic scar tissue with the near-complete absence of normal muscle. MRI 1 year later revealed the absence of relevant muscle regeneration. Persistent pain and inability to perform normal weight training were evident for at least 3 years post-surgery. This alarming finding indicating irreversible muscle mutilation may hopefully discourage people interested in bodybuilding and fitness from oil-injections. The impact of such chronic tissue stress on other diseases like malignancy remains to be determined. © Georg Thieme Verlag KG Stuttgart · New York.

  18. A comprehensive segmentation analysis of crude oil market based on time irreversibility

    Science.gov (United States)

    Xia, Jianan; Shang, Pengjian; Lu, Dan; Yin, Yi

    2016-05-01

    In this paper, we perform a comprehensive entropic segmentation analysis of crude oil future prices from 1983 to 2014 which used the Jensen-Shannon divergence as the statistical distance between segments, and analyze the results from original series S and series begin at 1986 (marked as S∗) to find common segments which have same boundaries. Then we apply time irreversibility analysis of each segment to divide all segments into two groups according to their asymmetry degree. Based on the temporal distribution of the common segments and high asymmetry segments, we figure out that these two types of segments appear alternately and do not overlap basically in daily group, while the common portions are also high asymmetry segments in weekly group. In addition, the temporal distribution of the common segments is fairly close to the time of crises, wars or other events, because the hit from severe events to oil price makes these common segments quite different from their adjacent segments. The common segments can be confirmed in daily group series, or weekly group series due to the large divergence between common segments and their neighbors. While the identification of high asymmetry segments is helpful to know the segments which are not affected badly by the events and can recover to steady states automatically. Finally, we rearrange the segments by merging the connected common segments or high asymmetry segments into a segment, and conjoin the connected segments which are neither common nor high asymmetric.

  19. Impaired Cargo Clearance in the Retinal Pigment Epithelium (RPE Underlies Irreversible Blinding Diseases

    Directory of Open Access Journals (Sweden)

    Eloise Keeling

    2018-02-01

    Full Text Available Chronic degeneration of the Retinal Pigment Epithelium (RPE is a precursor to pathological changes in the outer retina. The RPE monolayer, which lies beneath the neuroretina, daily internalises and digests large volumes of spent photoreceptor outer segments. Impaired cargo handling and processing in the endocytic/phagosome and autophagy pathways lead to the accumulation of lipofuscin and pyridinium bis-retinoid A2E aggregates and chemically modified compounds such as malondialdehyde and 4-hydroxynonenal within RPE. These contribute to increased proteolytic and oxidative stress, resulting in irreversible damage to post-mitotic RPE cells and development of blinding conditions such as age-related macular degeneration, Stargardt disease and choroideremia. Here, we review how impaired cargo handling in the RPE results in their dysfunction, discuss new findings from our laboratory and consider how newly discovered roles for lysosomes and the autophagy pathway could provide insights into retinopathies. Studies of these dynamic, molecular events have also been spurred on by recent advances in optics and imaging technology. Mechanisms underpinning lysosomal impairment in other degenerative conditions including storage disorders, α-synuclein pathologies and Alzheimer’s disease are also discussed. Collectively, these findings help transcend conventional understanding of these intracellular compartments as simple waste disposal bags to bring about a paradigm shift in the way lysosomes are perceived.

  20. Dislocation reactions, grain boundaries, and irreversibility in two-dimensional lattices using topological tweezers.

    Science.gov (United States)

    Irvine, William T M; Hollingsworth, Andrew D; Grier, David G; Chaikin, Paul M

    2013-09-24

    Dislocations, disclinations, and grain boundaries are topological excitations of crystals that play a key role in determining out-of-equilibrium material properties. In this article we study the kinetics, creation, and annihilation processes of these defects in a controllable way by applying "topological tweezers," an array of weak optical tweezers which strain the lattice by weakly pulling on a collection of particles without grabbing them individually. We use topological tweezers to deterministically control individual dislocations and grain boundaries, and reversibly create and destroy dislocation pairs in a 2D crystal of charged colloids. Starting from a perfect lattice, we exert a torque on a finite region and follow the complete step-by-step creation of a disoriented grain, from the creation of dislocation pairs through their reactions to form a grain boundary and their reduction of elastic energy. However, when the grain is rotated back to its original orientation the dislocation reactions do not retrace. Rather, the process is irreversible; the grain boundary expands instead of collapsing.

  1. Modified procedure for secondary facial rehabilitation following total bilateral irreversible peripheral facial palsy.

    Science.gov (United States)

    Barabás, József; Klenk, Gusztáv; Szabó, György; Lukáts, Olga; Bogdán, Sándor; Decker, Iván; Huszár, Tamás

    2007-01-01

    We present the case of a middle-aged gentleman who developed total bilateral irreversible peripheral facial palsy over a period of 10 years, starting with palsy of the marginal mandibular and buccal branches of the facial nerve and progressing to the zygomatic and temporal branches. The patient did not develop any other neurological symptoms, and all neurological and other tests have remained negative over the last 10 years. Dripping of saliva and inability to close the mouth necessitated reanimation of the perioral region with the help of a fascia lata graft fixed to the fascia of the masseter muscles. The increasing lagophthalmos and associated eye problems were alleviated with a temporal muscle transposition combined with a lengthening procedure using the temporal fascia, passed through the upper and lower eyelids and hooked around the medial canthal ligament. The fascia strips were sutured not to the canthal ligament itself, but to each other, thereby placing equal self-adjusted tension on the upper and lower eyelids. Both operations were successful and improved eating and eye closure functions, allowing resolution of the eye symptoms.

  2. A statistical model describing combined irreversible electroporation and electroporation-induced blood-brain barrier disruption.

    Science.gov (United States)

    Sharabi, Shirley; Kos, Bor; Last, David; Guez, David; Daniels, Dianne; Harnof, Sagi; Mardor, Yael; Miklavcic, Damijan

    2016-03-01

    Electroporation-based therapies such as electrochemotherapy (ECT) and irreversible electroporation (IRE) are emerging as promising tools for treatment of tumors. When applied to the brain, electroporation can also induce transient blood-brain-barrier (BBB) disruption in volumes extending beyond IRE, thus enabling efficient drug penetration. The main objective of this study was to develop a statistical model predicting cell death and BBB disruption induced by electroporation. This model can be used for individual treatment planning. Cell death and BBB disruption models were developed based on the Peleg-Fermi model in combination with numerical models of the electric field. The model calculates the electric field thresholds for cell kill and BBB disruption and describes the dependence on the number of treatment pulses. The model was validated using in vivo experimental data consisting of rats brains MRIs post electroporation treatments. Linear regression analysis confirmed that the model described the IRE and BBB disruption volumes as a function of treatment pulses number (r(2) = 0.79; p disruption, the ratio increased with the number of pulses. BBB disruption radii were on average 67% ± 11% larger than IRE volumes. The statistical model can be used to describe the dependence of treatment-effects on the number of pulses independent of the experimental setup.

  3. Analysis and optimization with ecological objective function of irreversible single resonance energy selective electron heat engines

    International Nuclear Information System (INIS)

    Zhou, Junle; Chen, Lingen; Ding, Zemin; Sun, Fengrui

    2016-01-01

    Ecological performance of a single resonance ESE heat engine with heat leakage is conducted by applying finite time thermodynamics. By introducing Nielsen function and numerical calculations, expressions about power output, efficiency, entropy generation rate and ecological objective function are derived; relationships between ecological objective function and power output, between ecological objective function and efficiency as well as between power output and efficiency are demonstrated; influences of system parameters of heat leakage, boundary energy and resonance width on the optimal performances are investigated in detail; a specific range of boundary energy is given as a compromise to make ESE heat engine system work at optimal operation regions. Comparing performance characteristics with different optimization objective functions, the significance of selecting ecological objective function as the design objective is clarified specifically: when changing the design objective from maximum power output into maximum ecological objective function, the improvement of efficiency is 4.56%, while the power output drop is only 2.68%; when changing the design objective from maximum efficiency to maximum ecological objective function, the improvement of power output is 229.13%, and the efficiency drop is only 13.53%. - Highlights: • An irreversible single resonance energy selective electron heat engine is studied. • Heat leakage between two reservoirs is considered. • Power output, efficiency and ecological objective function are derived. • Optimal performance comparison for three objective functions is carried out.

  4. Irreversible splenic atrophy following chronic LCMV infection is associated with compromised immunity in mice.

    Science.gov (United States)

    Mbanwi, Achire N; Wang, Chao; Geddes, Kaoru; Philpott, Dana J; Watts, Tania H

    2017-01-01

    Lymphocytic choriomeningitis virus clone 13 (LCMV13) infection of mice is a widely used model for investigating the mechanisms driving persistent viral infection in humans. LCMV13 disrupts splenic architecture early during infection, but this returns to normal within a few weeks. However, the long-term effects of LCMV13 infection on splenic structure have not been reported. Here, we report that persistent infection with LCMV13 results in sustained splenic atrophy that persists for at least 500 days following infection, whereas infection with the acutely infecting LCMV Armstrong is associated with a return to preinfection spleen weights. Splenic atrophy is associated with loss of T, B, and non-B non-T cells, with B cells most significantly affected. These effects were partly ameliorated by anti-NK1.1 or anti-CD8 antibody treatment. Antigen presentation was detectable at the time of contraction of the spleen, but no longer detected at late time points, suggesting that continued antigen presentation is not required to maintain splenic atrophy. Immunity to Salmonella infection and influenza vaccination were decreased after the virus was no longer detected. Thus splenic atrophy following LCMV13 infection is irreversible and may contribute to impaired immunity following clearance of LCMV13. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Context-aware system for pre-triggering irreversible vehicle safety actuators.

    Science.gov (United States)

    Böhmländer, Dennis; Dirndorfer, Tobias; Al-Bayatti, Ali H; Brandmeier, Thomas

    2017-06-01

    New vehicle safety systems have led to a steady improvement of road safety and a reduction in the risk of suffering a major injury in vehicle accidents. A huge leap forward in the development of new vehicle safety systems are actuators that have to be activated irreversibly shortly before a collision in order to mitigate accident consequences. The triggering decision has to be based on measurements of exteroceptive sensors currently used in driver assistance systems. This paper focuses on developing a novel context-aware system designed to detect potential collisions and to trigger safety actuators even before an accident occurs. In this context, the analysis examines the information that can be collected from exteroceptive sensors (pre-crash data) to predict a certain collision and its severity to decide whether a triggering is entitled or not. A five-layer context-aware architecture is presented, that is able to collect contextual information about the vehicle environment and the actual driving state using different sensors, to perform reasoning about potential collisions, and to trigger safety functions upon that information. Accident analysis is used in a data model to represent uncertain knowledge and to perform reasoning. A simulation concept based on real accident data is introduced to evaluate the presented system concept. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Isothermal chemical denaturation of large proteins: Path-dependence and irreversibility.

    Science.gov (United States)

    Wafer, Lucas; Kloczewiak, Marek; Polleck, Sharon M; Luo, Yin

    2017-12-15

    State functions (e.g., ΔG) are path independent and quantitatively describe the equilibrium states of a thermodynamic system. Isothermal chemical denaturation (ICD) is often used to extrapolate state function parameters for protein unfolding in native buffer conditions. The approach is prudent when the unfolding/refolding processes are path independent and reversible, but may lead to erroneous results if the processes are not reversible. The reversibility was demonstrated in several early studies for smaller proteins, but was assumed in some reports for large proteins with complex structures. In this work, the unfolding/refolding of several proteins were systematically studied using an automated ICD instrument. It is shown that: (i) the apparent unfolding mechanism and conformational stability of large proteins can be denaturant-dependent, (ii) equilibration times for large proteins are non-trivial and may introduce significant error into calculations of ΔG, (iii) fluorescence emission spectroscopy may not correspond to other methods, such as circular dichroism, when used to measure protein unfolding, and (iv) irreversible unfolding and hysteresis can occur in the absence of aggregation. These results suggest that thorough confirmation of the state functions by, for example, performing refolding experiments or using additional denaturants, is needed when quantitatively studying the thermodynamics of protein unfolding using ICD. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Effects of design conditions and irreversibilities on the dimensions of ejectors in refrigeration systems

    International Nuclear Information System (INIS)

    Khennich, Mohammed; Galanis, Nicolas; Sorin, Mikhail

    2016-01-01

    Highlights: • New model uses polytropic efficiencies η pol and determines all ejector dimensions. • The effects of η pol on ejector dimensions and mixing efficiency are evaluated. • The effects of inlet/outlet conditions on ejector dimensions are evaluated. • The total exergy losses increase linearly when the mixing efficiency decreases. • Inlet/outlet pressures which reduce exergy losses and total length are determined. - Abstract: A thermodynamic model for the design of ejectors is described, validated and applied for conditions prevailing in refrigeration systems. Contrary to previous models the present one determines all the dimensions of the ejector and uses polytropic (instead of isentropic) efficiencies thus taking into account the effects of the pressure ratio on the entropy increase during the irreversible acceleration and deceleration processes. The results include dimensions and fluid properties for a base case as well as a parametric study which analyzes the effect of inlet and outlet conditions on the dimensions and efficiencies of the acceleration, deceleration and mixing processes. The parametric study coupled to recommended constraints from the literature leads to the determination of design conditions for which the axial evolution of pressure, temperature and velocity are determined. The effects of the polytropic efficiency on the ejector dimensions and the efficiencies of the processes taking place in the ejector are also presented and analysed. It is also shown that the total exergy losses increase linearly when the mixing efficiency decreases.

  8. Local equilibrium and the second law of thermodynamics for irreversible systems with thermodynamic inertia

    International Nuclear Information System (INIS)

    Glavatskiy, K. S.

    2015-01-01

    Validity of local equilibrium has been questioned for non-equilibrium systems which are characterized by delayed response. In particular, for systems with non-zero thermodynamic inertia, the assumption of local equilibrium leads to negative values of the entropy production, which is in contradiction with the second law of thermodynamics. In this paper, we address this question by suggesting a variational formulation of irreversible evolution of a system with non-zero thermodynamic inertia. We introduce the Lagrangian, which depends on the properties of the normal and the so-called “mirror-image” systems. We show that the standard evolution equations, in particular, the Maxwell-Cattaneo-Vernotte equation, can be derived from the variational procedure without going beyond the assumption of local equilibrium. We also argue that the second law of thermodynamics in non-equilibrium should be understood as a consequence of the variational procedure and the property of local equilibrium. For systems with instantaneous response this leads to the standard requirement of the local instantaneous entropy production being always positive. However, if a system is characterized by delayed response, the formulation of the second law of thermodynamics should be altered. In particular, the quantity, which is always positive, is not the instantaneous entropy production, but the entropy production averaged over a proper time interval

  9. Local equilibrium and the second law of thermodynamics for irreversible systems with thermodynamic inertia.

    Science.gov (United States)

    Glavatskiy, K S

    2015-10-28

    Validity of local equilibrium has been questioned for non-equilibrium systems which are characterized by delayed response. In particular, for systems with non-zero thermodynamic inertia, the assumption of local equilibrium leads to negative values of the entropy production, which is in contradiction with the second law of thermodynamics. In this paper, we address this question by suggesting a variational formulation of irreversible evolution of a system with non-zero thermodynamic inertia. We introduce the Lagrangian, which depends on the properties of the normal and the so-called "mirror-image" systems. We show that the standard evolution equations, in particular, the Maxwell-Cattaneo-Vernotte equation, can be derived from the variational procedure without going beyond the assumption of local equilibrium. We also argue that the second law of thermodynamics in non-equilibrium should be understood as a consequence of the variational procedure and the property of local equilibrium. For systems with instantaneous response this leads to the standard requirement of the local instantaneous entropy production being always positive. However, if a system is characterized by delayed response, the formulation of the second law of thermodynamics should be altered. In particular, the quantity, which is always positive, is not the instantaneous entropy production, but the entropy production averaged over a proper time interval.

  10. Irreversible electroporation and the pancreas: What we know and where we are going?

    Science.gov (United States)

    Young, Shamar J

    2015-08-27

    Pancreatic adenocarcinoma continues to have a poor prognosis with 1 and 5 years survival rates of 27% and 6% respectively. The gold standard of treatment is resection, however, only approximately 10% of patients present with resectable disease. Approximately 40% of patients present with disease that is too locally advanced to resect. There is great interest in improving outcomes in this patient population and ablation techniques have been investigated as a potential solution. Unfortunately early investigations into thermal ablation techniques, particularly radiofrequency ablation, resulted in unacceptably high morbidity rates. Irreversible electroporation (IRE) has been introduced and is promising as it does not rely on thermal energy and has shown an ability to leave structural cells such as blood vessels and bile ducts intact during animal studies. IRE also does not suffer from heat sink effect, a concern given the large number of blood vessels surrounding the pancreas. IRE showed significant promise during preclinical animal trials and as such has moved on to clinical testing. There are as of yet only a few studies which look at the applications of IRE within humans in the setting of pancreatic adenocarcinoma. This paper reviews the basic principles, techniques, and current clinical data available on IRE.

  11. Performance analysis of irreversible quantum Stirling cryogenic refrigeration cycles and their parametric optimum criteria

    International Nuclear Information System (INIS)

    Lin Bihong; Chen Jincan

    2006-01-01

    The influence of both the quantum degeneracy and the finite-rate heat transfer between the working substance and the heat reservoirs on the optimal performance of an irreversible Stirling cryogenic refrigeration cycle using an ideal Fermi or Bose gas as the working substance is investigated, based on the theory of statistical mechanics and thermodynamic properties of ideal quantum gases. The inherent regeneration losses of the cycle are analysed. Expressions for several important performance parameters such as the coefficient of performance, cooling rate and power input are derived. By using numerical solutions, the cooling rate of the cycle is optimized for a given power input. The maximum cooling rate and the corresponding parameters are calculated numerically. The optimal regions of the coefficient of performance and power input are determined. In particular, the optimal performance of the cycle in the strong and weak gas degeneracy cases and the high temperature limit are discussed in detail. The analytic expressions of some optimized parameters are derived. Some optimum criteria are given. The distinctions and connections between the Stirling refrigeration cycles working with the ideal quantum and classical gases are revealed

  12. A case of community-based fall prevention: Survey of organization and content of minor home help services in Swedish municipalities.

    Science.gov (United States)

    Bernfort, Lars; Eckard, Nathalie; Husberg, Magnus; Alwin, Jenny

    2014-11-01

    The aim of this study was to survey minor home help services provided by Swedish municipalities with the main purpose to prevent fall injuries. If minor home help services were presented on the homepage of a municipality, an initial telephone contact was taken. Thereafter a questionnaire was administered, including questions about target groups, aim with the services, tasks included, costs and restrictions for users, budget, and experienced gains with the services. Municipalities not providing minor home help services were asked about the reason therefore and if the municipality had previously provided the services Results: The questionnaire response rate was 92%. In 191 of Sweden's 290 municipalities services were provided by, or in cooperation with, the municipality. Reasons for not providing the services were mainly financial and lack of demand. Services were more often provided in larger cities and in municipalities located in populous regions. In some municipalities services were performed by persons with functional disabilities or unemployed persons. Both providers and users expressed satisfaction with the services aspects expressed were that services lead to greater sense of safety and social gains the effect of the services in terms of fall prevention is yet to be proved with only a small fall-preventive effect services are probably cost-effective improved quality of life, sense of safety, and being able to offer meaningful work to otherwise unemployed persons are important aspects that might in themselves motivate the provision of minor home help services. © 2014 the Nordic Societies of Public Health.

  13. Estimation of Epidemiological Effectiveness of the Program of Pharmaceutical Prevention of Influenza and ARVI «Antigripp» in Organized Children's Groups

    Directory of Open Access Journals (Sweden)

    I. B. Yakovlev

    2012-01-01

    Full Text Available The authors estimated epidemiological effectiveness of the program for prophylaxis of influenza and ARVI «Antigripp» for children of 7—12 years old. Children received Arbidol (capsules of 100 mg 2 times a week for 3 weeks and Complivit activ. As a result there was a decline in absolute and relative indicators of ARVI morbidity risks. Epidemiological effectiveness of the program during the application of the drugs made up 56% and index of preventive efficacy was 2,3.

  14. Use of cadmium in solution in the EL 4 reactor moderator irreversible fixing of cadmium on the metallic surfaces; Utilisation du cadmium en solution dans le moderateur du reacteur EL 4 - fixation irreversible du cadmium sur les surfaces metalliques

    Energy Technology Data Exchange (ETDEWEB)

    Croix, O.; Paoli, O.; Lecomte, J.; Dolle, L.; Gallic, Y. [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1964-07-01

    In the framework of research into the poisoning of the EL-4 reactor by cadmium sulphate, measurements have been made by two different methods of the residual amounts of cadmium liable to be fixed irreversibly on the surfaces in contact with the heavy water. A marked influence of the pH has been noticed. The mechanism of the irreversible fixing is compatible with the hypothesis of an ion-exchange in the surface oxide layer. In a sufficiently wide range of pH the cadmium thus fixed causes very little residual poisoning. The stability of the cadmium sulphate solutions is however rather low in the conditions of poisoning. (authors) [French] Dans le cadre des etudes sur l'empoisonnement du reacteur EL-4 par le sulfate de cadmium, les quantites residuelles de cadmium susceptibles de se fixer irreversiblement sur les parois que mouillerait l'eau lourde, ont ete mesurees experimentalement par deux methodes differentes. On observe une influence nette du pH. Le mecanisme de la fixation irreversible est compatible avec l'hypothese d'un echange d'ions dans la pellicule d'oxyde superficielle. Dans des limites suffisamment larges de pH, la cadmium ainsi fixe n'occasionne pas d'empoisonnement residuel important. La stabilite des solutions de sulfate de cadmium dans les conditions de l'empoisonnement est cependant mediocre. (auteurs)

  15. Planning Irreversible Electroporation in the Porcine Kidney: Are Numerical Simulations Reliable for Predicting Empiric Ablation Outcomes?

    Energy Technology Data Exchange (ETDEWEB)

    Wimmer, Thomas, E-mail: thomas.wimmer@medunigraz.at; Srimathveeravalli, Govindarajan; Gutta, Narendra [Memorial Sloan-Kettering Cancer Center, Interventional Radiology Service, Department of Radiology (United States); Ezell, Paula C. [The Rockefeller University, Research Animal Resource Center, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College (United States); Monette, Sebastien [The Rockefeller University, Laboratory of Comparative Pathology, Memorial Sloan-Kettering Cancer Center, Weill Cornell Medical College (United States); Maybody, Majid; Erinjery, Joseph P.; Durack, Jeremy C. [Memorial Sloan-Kettering Cancer Center, Interventional Radiology Service, Department of Radiology (United States); Coleman, Jonathan A. [Memorial Sloan-Kettering Cancer Center, Urology Service, Department of Surgery (United States); Solomon, Stephen B. [Memorial Sloan-Kettering Cancer Center, Interventional Radiology Service, Department of Radiology (United States)

    2015-02-15

    PurposeNumerical simulations are used for treatment planning in clinical applications of irreversible electroporation (IRE) to determine ablation size and shape. To assess the reliability of simulations for treatment planning, we compared simulation results with empiric outcomes of renal IRE using computed tomography (CT) and histology in an animal model.MethodsThe ablation size and shape for six different IRE parameter sets (70–90 pulses, 2,000–2,700 V, 70–100 µs) for monopolar and bipolar electrodes was simulated using a numerical model. Employing these treatment parameters, 35 CT-guided IRE ablations were created in both kidneys of six pigs and followed up with CT immediately and after 24 h. Histopathology was analyzed from postablation day 1.ResultsAblation zones on CT measured 81 ± 18 % (day 0, p ≤ 0.05) and 115 ± 18 % (day 1, p ≤ 0.09) of the simulated size for monopolar electrodes, and 190 ± 33 % (day 0, p ≤ 0.001) and 234 ± 12 % (day 1, p ≤ 0.0001) for bipolar electrodes. Histopathology indicated smaller ablation zones than simulated (71 ± 41 %, p ≤ 0.047) and measured on CT (47 ± 16 %, p ≤ 0.005) with complete ablation of kidney parenchyma within the central zone and incomplete ablation in the periphery.ConclusionBoth numerical simulations for planning renal IRE and CT measurements may overestimate the size of ablation compared to histology, and ablation effects may be incomplete in the periphery.

  16. Percutaneous Irreversible Electroporation Lung Ablation: Preliminary Results in a Porcine Model

    International Nuclear Information System (INIS)

    Deodhar, Ajita; Monette, Sébastien; Single, Gordon W.; Hamilton, William C.; Thornton, Raymond H.; Sofocleous, Constantinos T.; Maybody, Majid; Solomon, Stephen B.

    2011-01-01

    Objective: Irreversible electroporation (IRE) uses direct electrical pulses to create permanent “pores” in cell membranes to cause cell death. In contrast to conventional modalities, IRE has a nonthermal mechanism of action. Our objective was to study the histopathological and imaging features of IRE in normal swine lung. Materials and Methods: Eleven female swine were studied for hyperacute (8 h), acute (24 h), subacute (96 h), and chronic (3 week) effects of IRE ablation in lung. Paired unipolar IRE applicators were placed under computed tomography (CT) guidance. Some applicators were deliberately positioned near bronchovascular structures. IRE pulse delivery was synchronized with the cardiac rhythm only when ablation was performed within 2 cm of the heart. Contrast-enhanced CT scan was performed immediately before and after IRE and at 1 and 3 weeks after IRE ablation. Representative tissue was stained with hematoxylin and eosin for histopathology. Results: Twenty-five ablations were created: ten hyperacute, four acute, and three subacute ablations showed alveolar edema and necrosis with necrosis of bronchial, bronchiolar, and vascular epithelium. Bronchovascular architecture was maintained. Chronic ablations showed bronchiolitis obliterans and alveolar interstitial fibrosis. Immediate post-procedure CT images showed linear or patchy density along the applicator tract. At 1 week, there was consolidation that resolved partially or completely by 3 weeks. Pneumothorax requiring chest tube developed in two animals; no significant cardiac arrhythmias were noted. Conclusion: Our preliminary porcine study demonstrates the nonthermal and extracellular matrix sparing mechanism of action of IRE. IRE is a potential alternative to thermal ablative modalities.

  17. Recognition of reversible and irreversible myocardial injury by technetium pyrophosphate extraction kinetics

    International Nuclear Information System (INIS)

    Silva, R.; Chen, Y.F.; Sell, T.L.; Lowe, J.E.; Jones, R.H.

    1987-01-01

    The need for a more accurate method of detecting episodes of myocardial ischemia during cardiac operations, particularly during the ischemic arrest interval, prompted us to investigate the usefulness of measuring the active extraction of technetium pyrophosphate in identifying and quantitating ischemic injury. Twenty-four adult mongrel dogs were subjected to cardiopulmonary bypass, and normothermic global ischemia was induced by cross-clamping the proximal aorta. Technetium pyrophosphate (1 mCi) was injected through a standard cardioplegia line with normal saline, simulating administration of cardioplegic solution, upon placement of the aortic cross-clamp (time 0), at 15, 30, 45, and 60 minutes of global ischemia, and with the onset and completion of ischemic contracture. Radioactive counts were recorded over the heart at 1 second intervals, and the extraction fraction and half-time of clearance were calculated. The extraction fraction increased from 0.22 at time 0 to 0.58 at 15 minutes, 0.82 at 30 minutes, 0.85 at 45 minutes, and 0.91 at 60 minutes. The halftime increased from a baseline of 114 seconds (time 0) to a maximum of 321 seconds at 60 minutes of ischemia. The onset and completion of ischemic contracture showed a return toward baseline of both the extraction fraction and halftime of clearance, with an extraction fraction of 0.44 and 0.46 and a halftime of 135 and 133 seconds, respectively. These data clearly show that reversible myocardial injury increased the extraction and reduced the clearance of technetium pyrophosphate and that the magnitude of change related to the extent of injury. The progression to irreversible myocardial injury decreased the active extraction of technetium pyrophosphate. This simple procedure for real-time documentation of myocardial injury promises to provide easily obtainable endpoints of injury for use during cardiac operations in humans

  18. Computational modeling of the hematopoietic erythroid-myeloid switch reveals insights into cooperativity, priming, and irreversibility.

    Directory of Open Access Journals (Sweden)

    Vijay Chickarmane

    2009-01-01

    Full Text Available Hematopoietic stem cell lineage choices are decided by genetic networks that are turned ON/OFF in a switch-like manner. However, prior to lineage commitment, genes are primed at low expression levels. Understanding the underlying molecular circuitry in terms of how it governs both a primed state and, at the other extreme, a committed state is of relevance not only to hematopoiesis but also to developmental systems in general. We develop a computational model for the hematopoietic erythroid-myeloid lineage decision, which is determined by a genetic switch involving the genes PU.1 and GATA-1. Dynamical models based upon known interactions between these master genes, such as mutual antagonism and autoregulation, fail to make the system bistable, a desired feature for robust lineage determination. We therefore suggest a new mechanism involving a cofactor that is regulated as well as recruited by one of the master genes to bind to the antagonistic partner that is necessary for bistability and hence switch-like behavior. An interesting fallout from this architecture is that suppression of the cofactor through external means can lead to a loss of cooperativity, and hence to a primed state for PU.1 and GATA-1. The PU.1-GATA-1 switch also interacts with another mutually antagonistic pair, C/EBPalpha-FOG-1. The latter pair inherits the state of its upstream master genes and further reinforces the decision due to several feedback loops, thereby leading to irreversible commitment. The genetic switch, which handles the erythroid-myeloid lineage decision, is an example of a network that implements both a primed and a committed state by regulating cooperativity through recruitment of cofactors. Perturbing the feedback between the master regulators and downstream targets suggests potential reprogramming strategies. The approach points to a framework for lineage commitment studies in general and could aid the search for lineage-determining genes.

  19. AGEs/RAGE in CKD: irreversible metabolic memory road toward CVD?

    Science.gov (United States)

    Koyama, Hidenori; Nishizawa, Yoshiki

    2010-07-01

    Cardiovascular disease is the major cause of death in patients with renal insufficiency, accounting for 50% of all deaths in renal replacement therapy patients. Mortality from cardiovascular diseases in these patients is approximately 9% per year, which is about 30 times the risk in the general population. So far, intensive interventions to the general risk factors, such as high LDL-cholesterol or C-reactive protein, have not been successful in improving their cardiovascular outcomes, suggesting that the beneficial effect of risk reduction may be overwhelmed by accumulated risk memorized by long-term exposure to oxidative stress during the progression of renal failure. In this review, we propose that this irreversible memory effect in renal failure may be mediated by advanced glycation end-products (AGEs). The generation of AGEs has been implicated to be deeply associated with increased oxidative stress. Moreover, interaction of the receptor for AGEs (RAGE) with AGEs leads to crucial biomedical pathway generating intracellular oxidative stress and inflammatory mediators, which could result in further amplification of the pathway involved in AGE generation. Several lines of evidence suggest that AGEs/RAGE axis can profoundly be involved in cardiovascular diseases. Recent advances in AGEs and RAGE measurements led us to be capable of understanding more about the role of AGEs/RAGE axis as a risk for cardiovascular diseases in patients with renal failure. AGEs/RAGE axis could be a crucial mediator of oxidative stress in renal failure. RAGE could be not only a useful biomarker, but also a potentially therapeutic target to overcome the accumulated adverse metabolic memory in renal failure.

  20. Further Insight Relative to Cavity Radiation III: Gedanken Experiments, Irreversibility, and Kirchhoff's Law

    Directory of Open Access Journals (Sweden)

    Robitaille P.-M.

    2016-01-01

    Full Text Available Recently, gedanken experiments have been proposed in order to examine the validity of Kirchhoff’s Law of Thermal Emission (P.-M. Robitaille, Further Insight Relative to Cavity Radiation: A Thought Experiment Refuting Kirchhoff’s Law, Prog. Phys., 2014, v. 10, no. 1, 38–40; P.-M. Robitaille, Further Insight Relative to Cavity Radiation II: Gedanken Experiments and Kirchhoff’s Law, Prog. Phys., 2014, v. 10, no. 2, 116–120. In the second of these works, real materials (i.e. graphite and silver were utilized in or- der to construct two separate cavities at the same temperature which are then placed in thermal contact with one another. It was hypothesized that the graphite cavity initially contained blackbody radiation and that the silver cavity was devoid of radiation. In the case of the silver cavity, all of the energy of the system was assigned to the phonons in its walls. When the cavities were brought together and a small hole introduced between the cavities, it was hypothesized that thermal contact between the cavity walls would enable the transformation of phonon energy into photon energy, eventually resulting in filling the silver cavity with black radiation. Energy contained within the wall of the silver cavity was believed to be reversibly trapped. However, in allowing energy to flow reversibly out of the walls of the silver cavity in this context, it has been assumed that the silver conduction bands could be neglected and that only phonon energy need be considered. However, the reflectivity attributed to the silver cavity should be con- sidered uniquely as a result of energy associated with the formation of its conduction bands. Such formation must be considered irreversible. It will be demonstrated that under these conditions Kirchhoff’s law, once again, does not hold. The lack of ther- mal radiation within the silver cavity does not lead to a violation of the second law of thermodynamics.