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Sample records for acids current approaches

  1. Current approach to male infertility treatment: sperm selection procedure based on hyaluronic acid binding ability

    A. V. Zobova

    2015-01-01

    Full Text Available Intracytoplasmic sperm injection into an oocyte is widely used throughout the world in assisted reproductive technologies programs in the presence of male infertility factor. However, this approach can allow selection of a single sperm, which is carrying different types of pathologies. Minimizing of any potential risks, entailing the occurrence of abnormalities in the embryos development (apoptosis, fragmentation of embryos, alterations in gene expression, aneuploidies is a very important condition for reducing the potential negative consequences resulting the manipulation with gametes. Processes that could be influenced by the embryologist must be fulfilled in safe and physiological way as much as it is possible. Data of numerous publications reporting about the positive effects of using the technology of sperm selection by hyaluronic acid binding, let make a conclusion about the high prospects of this approach in the treatment of male infertility by methods of in vitro fertilization. The selection of sperm with improved characteristics, which determine the maturity and genetic integrity, provides an opportunity to improve the parameters of pre-implantation embryogenesis, having thus a positive effect on clinical outcomes of assisted reproductive technologies programs.

  2. Nanorobotics current approaches and techniques

    Ferreira, Antoine

    2013-01-01

    Nanorobot devices now perform a wide variety of tasks at the nanoscale in a wide variety of fields including but not limited to fields such as manufacturing, medicine, supply chain, biology, and outer space. Nanorobotics: Current Approaches and Techniques is a comprehensive overview of this interdisciplinary field with a wide ranging discussion that includes nano-manipulation and industrial nanorobotics, nanorobotics in biology and medicine, nanorobotic sensing, navigation and swarm behavior, and protein and DNA-based nanorobotics. Also included is the latest on topics such as bio-nano-actuators and propulsion and navigation of nanorobotic systems using magnetic fields. Nanorobotics: Current Approaches and Techniques is an ideal book for scientists, researchers, and engineers actively involved in applied and robotic research and development.

  3. Reconciling current approaches to blindsight

    Overgaard, Morten; Mogensen, Jesper

    2015-01-01

    After decades of research, blindsight is still a mysterious and controversial topic in consciousness research. Currently, many researchers tend to think of it as an ideal phenomenon to investigate neural correlates of consciousness, whereas others believe that blindsight is in fact a kind of...

  4. Carious dentine removal: current approach

    Germana Coeli de Farias Sales

    2008-01-01

    Full Text Available Dentistry is renewed day after day through the results of qualified researches. The approach as regards carious dentin removal is goingthrough questioning and innovation. The scope of this study was to perform a literature review in the sense of elucidating questions pertaining to the problem of whether or not it is necessary to completely remove carious dentin, and the possibility of performing restoration in a single session, in addition to a discussion about which type of material should be applied in this type of substrate. After analyzing the referenced articles, it was concluded that the stepwise treatment controls caries progression; there is a trend in the literature to partially remove the carious dentin in deep lesions and perform definitive restoration; Calcium hydroxide cement is a classical liner in these situations, while glass ionomer cement and resinous materials are other possibilities of materials that can be in close contact with the remaining dentin.

  5. Crohn's disease: current imaging approach

    Purpose: This paper discusses the role of different imaging modalities in the diagnostic work-up of Crohn's disease (CD). Methods: We present a concept, which emphasizes different diagnostic aspects with regard to primary diagnosis, follow-up and assessment of complications of CD. The most effective imaging approach to various diagnostic problems of CD is discussed in detail. Discussion: With regard to the primary diagnosis barium studies should contribute to differentiate between CD and ulcerative colitis. Beyond that, these studies should evaluate location and extent of disease. During the follow-up bowel sonography provides staging of disease and enables the detection of complications at an early stage. CT is a valuable tool in the preoperative assessment of complications, such as fistuale and abscesses. (orig.)

  6. Current Approach to Child Rights

    Huseyin Dag

    2015-03-01

    Full Text Available Rights of children, legally or morally all over the world that children are born with; education, health, life, shelter; physical, psychological or sexual exploitation protection of such rights is universal concept used to describethemall. Rights of children is an issue that should be addressed in the concept of human rights. Today, there are many parts of the world that human rights violations, child-size and grew broader, more difficult to intervene in a way that is situated. The idea that children than in adults of different physical, physiological, behavioral and psychological characteristics that continuous growth and improve dawareness that the establishment of thecare of children a society where the problem is and scientific approach everyone with this responsibility should be installed is shaped in Geneva Declaration of Childrens Rights. Today, the international document related to childrens rights is the United Nations Convention on the Rights of the Child adoptedand approved by 193 countries. Child policy in Turkey where 25 million children live is an issue that should be seriously considered. Thus, childrens rights, children working in coordination with the contract on the basis of a policy should be implemented fully. [Cukurova Med J 2015; 40(1.000: 1-5

  7. Current approaches to the management of diabetic retinopathy

    Tat'yana Yul'evna Demidova

    2014-06-01

    Full Text Available This review reflects the current status of the diabetic retinopathy treatment problem and describes the results of the largest trials on epidemiology, screening and the risk factors for complications. In addition, this article describes the current approaches and treatment options for diabetic retinopathy, including a description of fenofibroic acid with its mechanism of action and data from clinical trials. This article also contains information on antiangiogenic agents for intravitreal administration.

  8. Current approaches to the management of diabetic retinopathy

    Tat'yana Yul'evna Demidova; Yuliya Alexandrovna Trakhtenberg

    2014-01-01

    This review reflects the current status of the diabetic retinopathy treatment problem and describes the results of the largest trials on epidemiology, screening and the risk factors for complications. In addition, this article describes the current approaches and treatment options for diabetic retinopathy, including a description of fenofibroic acid with its mechanism of action and data from clinical trials. This article also contains information on antiangiogenic agents for intravitreal admi...

  9. Neutralized current acid waste consolidation management plan

    The scope of this evaluation is to recommend a management plan for the high-heat tank waste, including neutralized current acid waste (NCAW) in AY and AZ Tank Farms, and tank C-106 waste. The movement of solids, liquids and salt cake in the designated tank farms is included. Decision analysis techniques were used to determine a recommended alternative. The recommended course of action was replacement of a 75-hp mixer pump in tank AY-102 and in-tank concentration of tank AZ-102 supernate. The alternative includes transfer fo tank C-106 sludge to tank AY-102, then transfer to tank AY-102 and tank C-106 sludge to tank AZ-101 using the new 75-hp mixer pump installed in tank AY-102. Tank AZ-101 becomes a storage tank for high-level waste (HLW) sludge, with the capacity to mix and transfer sludge as desired

  10. Childhood obesity: Current and novel approaches.

    Sabin, Matthew A; Kiess, Wieland

    2015-06-01

    The prevalence of childhood obesity has increased over the last fifty years by approximately 5% per decade, and approximately a quarter of all children are now either overweight or obese. These children have a significantly increased risk of many future health problems including adult obesity, type 2 diabetes and heart disease. Despite this relentless increase, common-sense approaches aimed at prevention and treatment have failed to solve the problem. Current approaches at prevention have faced major challenges with some progress in implementing smaller scale programs and social marketing, but little action on broad public policy approaches which often appears unpalatable to society or individual governments. Meanwhile, treatment approaches have mainly focused on lifestyle change, and novel approaches are urgently needed. Prevention needs to shift to improving maternal health prior to conception, with more research focussed on the impact of early years in programming offspring to future overweight/obesity. Likewise, treatment paradigms need to move from simply thinking that obesity can be solved by readdressing diet and activity levels. Novel approaches are needed which take into consideration the complex physiology which regulates early childhood growth and the development of obesity in susceptible individuals. PMID:26051294

  11. Sedimentation of sulfuric acid in acid tars from current production

    Denisova, T.L.; Frolov, A.F.; Aminov, A.N.; Novosel' tsev, S.P.

    1987-09-01

    Acid tars obtained in treating T-750, KhF-12, and I-8A oils were investigated for purposes of recovering sulfuric acid and asphalt binders from the compositions and of determining the effects of storage time on the recovery. The consumption and sedimentation levels of sulfuric acid during storage for different periods and at different temperatures were assessed. The characteristics of an asphalt binder obtained by neutralizing acid tar with a paste consisting of asphalts from deasphalting operations and slaked lime, followed by oxidation of the mixture with atmospheric air, were determined. The sulfuric acid recovered in the settling process could be burned in order to purify it of organic contaminants.

  12. Current Approaches for Diagnosis of Influenza Virus Infections in Humans

    Vemula, Sai Vikram; Zhao, Jiangqin; Liu, Jikun; Wang, Xue; Biswas, Santanu; Hewlett, Indira

    2016-01-01

    Despite significant advancement in vaccine and virus research, influenza continues to be a major public health concern. Each year in the United States of America, influenza viruses are responsible for seasonal epidemics resulting in over 200,000 hospitalizations and 30,000–50,000 deaths. Accurate and early diagnosis of influenza viral infections are critical for rapid initiation of antiviral therapy to reduce influenza related morbidity and mortality both during seasonal epidemics and pandemics. Several different approaches are currently available for diagnosis of influenza infections in humans. These include viral isolation in cell culture, immunofluorescence assays, nucleic acid amplification tests, immunochromatography-based rapid diagnostic tests, etc. Newer diagnostic approaches are being developed to overcome the limitations associated with some of the conventional detection methods. This review discusses diagnostic approaches currently available for detection of influenza viruses in humans. PMID:27077877

  13. Computational Approaches to Nucleic Acid Origami.

    Jabbari, Hosna; Aminpour, Maral; Montemagno, Carlo

    2015-10-12

    Recent advances in experimental DNA origami have dramatically expanded the horizon of DNA nanotechnology. Complex 3D suprastructures have been designed and developed using DNA origami with applications in biomaterial science, nanomedicine, nanorobotics, and molecular computation. Ribonucleic acid (RNA) origami has recently been realized as a new approach. Similar to DNA, RNA molecules can be designed to form complex 3D structures through complementary base pairings. RNA origami structures are, however, more compact and more thermodynamically stable due to RNA's non-canonical base pairing and tertiary interactions. With all these advantages, the development of RNA origami lags behind DNA origami by a large gap. Furthermore, although computational methods have proven to be effective in designing DNA and RNA origami structures and in their evaluation, advances in computational nucleic acid origami is even more limited. In this paper, we review major milestones in experimental and computational DNA and RNA origami and present current challenges in these fields. We believe collaboration between experimental nanotechnologists and computer scientists are critical for advancing these new research paradigms. PMID:26348196

  14. Comparing Teaching Approaches About Maxwell's Displacement Current

    Karam, Ricardo; Coimbra, Debora; Pietrocola, Maurício

    2014-08-01

    Due to its fundamental role for the consolidation of Maxwell's equations, the displacement current is one of the most important topics of any introductory course on electromagnetism. Moreover, this episode is widely used by historians and philosophers of science as a case study to investigate several issues (e.g. the theory-experiment relationship). Despite the consensus among physics educators concerning the relevance of the topic, there are many possible ways to interpret and justify the need for the displacement current term. With the goal of understanding the didactical transposition of this topic more deeply, we investigate three of its domains: (1) The historical development of Maxwell's reasoning; (2) Different approaches to justify the term insertion in physics textbooks; and (3) Four lectures devoted to introduce the topic in undergraduate level given by four different professors. By reflecting on the differences between these three domains, significant evidence for the knowledge transformation caused by the didactization of this episode is provided. The main purpose of this comparative analysis is to assist physics educators in developing an epistemological surveillance regarding the teaching and learning of the displacement current.

  15. Therapeutic nucleic acids: current clinical status.

    Sridharan, Kannan; Gogtay, Nithya Jaideep

    2016-09-01

    Deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) are simple linear polymers that have been the subject of considerable research in the last two decades and have now moved into the realm of being stand-alone therapeutic agents. Much of this has stemmed from the appreciation that they carry out myriad functions that go beyond mere storage of genetic information and protein synthesis. Therapy with nucleic acids either uses unmodified DNA or RNA or closely related compounds. From both a development and regulatory perspective, they fall somewhere between small molecules and biologics. Several of these compounds are in clinical development and many have received regulatory approval for human use. This review addresses therapeutic uses of DNA based on antisense oligonucleotides, DNA aptamers and gene therapy; and therapeutic uses of RNA including micro RNAs, short interfering RNAs, ribozymes, RNA decoys and circular RNAs. With their specificity, functional diversity and limited toxicity, therapeutic nucleic acids hold enormous promise. However, challenges that need to be addressed include targeted delivery, mass production at low cost, sustaining efficacy and minimizing off-target toxicity. Technological developments will hold the key to this and help accelerate drug approvals in the years to come. PMID:27111518

  16. Computational approaches to analogical reasoning current trends

    Richard, Gilles

    2014-01-01

    Analogical reasoning is known as a powerful mode for drawing plausible conclusions and solving problems. It has been the topic of a huge number of works by philosophers, anthropologists, linguists, psychologists, and computer scientists. As such, it has been early studied in artificial intelligence, with a particular renewal of interest in the last decade. The present volume provides a structured view of current research trends on computational approaches to analogical reasoning. It starts with an overview of the field, with an extensive bibliography. The 14 collected contributions cover a large scope of issues. First, the use of analogical proportions and analogies is explained and discussed in various natural language processing problems, as well as in automated deduction. Then, different formal frameworks for handling analogies are presented, dealing with case-based reasoning, heuristic-driven theory projection, commonsense reasoning about incomplete rule bases, logical proportions induced by similarity an...

  17. Current Approach to Dry Eye Disease.

    Valim, Valéria; Trevisani, Virginia Fernandes Moça; de Sousa, Jacqueline Martins; Vilela, Verônica Silva; Belfort, Rubens

    2015-12-01

    Dry eye disease (DED) is a multifactorial disease of the tears and ocular surface that causes tear film instability with potential damage to the ocular surface. The prevalence of dry eye in the world population ranges from 6 to 34 %. It is more common in those aged over 50, and affects mainly women. Since the introduction of the Schirmer's test in 1903, other tests have been developed to evaluate dry eye, such as biomicroscopy, the tear film breakup time (BUT), vital dyes (lissamine green and rose bengal), fluorescein, leaf fern test, corneal sensitivity test, conjunctiva impression cytology, optical coherence tomography (OCT), and tear osmolarity measurement. Although there is no gold standard, it is advisable to combine at least two tests. Strategies for treating DED have recently been modified and include patient education, tear substitute, corticosteroids, secretagogues, fatty acids, immunomodulators, occlusion of lacrimal puncta surgery and, tarsorrhaphy. Biological therapy and new topical immunomodulators such as tacrolimus, tofacitinib and IL-1 receptor inhibitor are being tested. In this review, the evaluation tests for dry eye are compared and the main studies on treatment are presented, with emphasis on studies in patients with Sjögren's syndrome. The authors propose an approach for the management of dry eye. PMID:25081064

  18. Narcolepsy: current treatment options and future approaches

    Michel Billiard

    2008-06-01

    Full Text Available Michel BilliardDepartment of Neurology, Gui de Chauliac Hospital, Montpellier, FranceAbstract: The management of narcolepsy is presently at a turning point. Three main avenues are considered in this review: 1 Two tendencies characterize the conventional treatment of narcolepsy. Modafinil has replaced methylphenidate and amphetamine as the first-line treatment of excessive daytime sleepiness (EDS and sleep attacks, based on randomized, double blind, placebo-controlled clinical trials of modafinil, but on no direct comparison of modafinil versus traditional stimulants. For cataplexy, sleep paralysis, and hypnagogic hallucinations, new antidepressants tend to replace tricyclic antidepressants and selective serotonin reuptake inhibitors (SSRIs in spite of a lack of randomized, double blind, placebo-controlled clinical trials of these compounds; 2 The conventional treatment of narcolepsy is now challenged by sodium oxybate, the sodium salt of gammahydroxybutyrate, based on a series of randomized, double-blind, placebo-controlled clinical trials and a long-term open label study. This treatment has a fairly good efficacy and is active on all symptoms of narcolepsy. Careful titration up to an adequate level is essential both to obtain positive results and avoid adverse effects; 3 A series of new treatments are currently being tested, either in animal models or in humans, They include novel stimulant and anticataplectic drugs, endocrine therapy, and, more attractively, totally new approaches based on the present state of knowledge of the pathophysiology of narcolepsy with cataplexy, hypocretine-based therapies, and immunotherapy.Keywords: narcolepsy, treatment, conventional drugs, modafinil, sodium oxybate, future treatments

  19. Linearized dynamical approach to current algebra

    We study the original motivations searching for a nonlinear chiral Lagrangian to replace the linear sigma model while manifesting all the successful properties of current algebra and partial conservation of axial currents (PCAC). (author). 26 refs

  20. DIABETIC POLYNEUROPATHY: CURRENT APPROACHES TO DIAGNOSIS AND PATHOGENETIC THERAPY

    O. S. Levin

    2013-01-01

    Full Text Available The paper considers the current views of the prevalence, clinical picture, approaches to the diagnosis and treatment of one of the most commonneurological complications of diabetes mellitus – diabetic polyneuropathy, and both its somatic and autonomous manifestations. Neuropathy ismost common in diabetic patients and its clinical forms reflect the severe course of diabetes mellitus and serve as an unfavorable prognostic signthat is associated with an approximately 5-fold increase in mortality. At the same time, the timely detection and adequate correction of the manifestations of neuropathy may substantially improve quality of life in the patients. The possibilities of pathogenetic therapy for diabetic polyneuropathy associated mainly with the use of benfotiamine and alpha-lipoic acid, as well as symptomatic therapy for its individual manifestationsare considered.

  1. DIABETIC POLYNEUROPATHY: CURRENT APPROACHES TO DIAGNOSIS AND PATHOGENETIC THERAPY

    O. S. Levin

    2014-07-01

    Full Text Available The paper considers the current views of the prevalence, clinical picture, approaches to the diagnosis and treatment of one of the most commonneurological complications of diabetes mellitus – diabetic polyneuropathy, and both its somatic and autonomous manifestations. Neuropathy ismost common in diabetic patients and its clinical forms reflect the severe course of diabetes mellitus and serve as an unfavorable prognostic signthat is associated with an approximately 5-fold increase in mortality. At the same time, the timely detection and adequate correction of the manifestations of neuropathy may substantially improve quality of life in the patients. The possibilities of pathogenetic therapy for diabetic polyneuropathy associated mainly with the use of benfotiamine and alpha-lipoic acid, as well as symptomatic therapy for its individual manifestationsare considered.

  2. Current Immunotherapeutic Approaches in Pancreatic Cancer

    Shigeo Koido

    2011-01-01

    Full Text Available Pancreatic cancer is a highly aggressive and notoriously difficult to treat. As the vast majority of patients are diagnosed at advanced stage of the disease, only a small population is curative by surgical resection. Although gemcitabine-based chemotherapy is typically offered as standard of care, most patients do not survive longer than 6 months. Thus, new therapeutic approaches are needed. Pancreatic cancer cells that develop gemcitabine resistance would still be suitable targets for immunotherapy. Therefore, one promising treatment approach may be immunotherapy that is designed to target pancreatic-cancer-associated antigens. In this paper, we detail recent work in immunotherapy and the advances in concept of combination therapy of immunotherapy and chemotherapy. We offer our perspective on how to increase the clinical efficacy of immunotherapies for pancreatic cancer.

  3. Current Immunotherapeutic Approaches in Pancreatic Cancer

    Jianlin Gong; Shigeo Koido; Hisao Tajiri; Hideo Komita; Masaki Ito; Kan Uchiyama; Kenichi Satoh; Keisuke Nagatsuma; Hiroshi Matsudaira; Toyokazu Yukawa; Shunichi Odahara; Jimi Mitobe; Yoshihisa Namiki; Shintaro Tsukinaga; Akitaka Takahara

    2011-01-01

    Pancreatic cancer is a highly aggressive and notoriously difficult to treat. As the vast majority of patients are diagnosed at advanced stage of the disease, only a small population is curative by surgical resection. Although gemcitabine-based chemotherapy is typically offered as standard of care, most patients do not survive longer than 6 months. Thus, new therapeutic approaches are needed. Pancreatic cancer cells that develop gemcitabine resistance would still be suitable targets for immuno...

  4. Low Back Pain: Current Surgical Approaches

    Baliga, Santosh; Treon, Katrina; Craig, Niall John Angus

    2015-01-01

    Low back pain (LBP) is a worldwide phenomenon. The UK studies place LBP as the largest single cause of absence from work; up to 80% of the population will experience LBP at least once in their lifetime. Most individuals do not seek medical care and are not disabled by their pain once it is managed by nonoperative measures. However, around 10% of patients go on to develop chronic pain. This review outlines the basics of the traditional approach to spinal surgery for chronic LBP secondary to os...

  5. Current approaches in atrial fibrillation treatment

    Cenk Sarı

    2014-09-01

    Full Text Available Atrial fibrillation (AF is the most common sustained arrhythmia encountered in clinical practice. Its incidence increases with age. AF is classified into subtypes according to the duration and/or able to provide sinus rhytym. İnitially, patients should be evaluated for rhythm or rate control for appropriate treatment. Second stage of strategy aimed to investigate the feasibility of anticoagulation therapy. Recently, due to the progress made in treatment with rhythm control and anticoagulation therapy, either American or European guidelines have been renovated. These developments have taken place in the newly published guide. In this article, the current change in the management of AF is discussed.

  6. Current therapeutic approaches for plantar fasciitis

    Martinelli N

    2014-03-01

    Full Text Available Nicolò Martinelli, Carlo Bonifacini, Giovanni RomeoDepartment of Ankle and Foot Surgery, IRCCS Galeazzi Orthopaedic Institute, Milan, ItalyAbstract: Almost 1 million Americans are affected by plantar fasciitis (PF, which is the commonest cause of chronic heel pain. This condition is often managed conservatively, and many rehabilitation protocols, some with the aid of orthoses, have been adopted, with good-to-excellent clinical results. Although most cases of chronic PF can be successfully managed with a conservative approach, alternative treatments, including high-energy shock wave therapy and corticosteroid injections, are commonly accepted as second-line treatment when traditional conservative therapy fails. However, surgery is still an important mode of treatment. Recently, new minimally invasive surgical techniques that offer numerous advantages (faster recovery time, early weight-bearing, lower postoperative pain over standard surgical approaches have been proposed, with good results and low complication rates. The purpose of this review is to report new conservative and surgical techniques for the treatment of PF. A literature search for articles about plantar fasciitis was conducted on the PubMed database in order to identify publications addressing the treatments of PF. The literature suggests that, initially, traditional conservative treatments consisting of rest, oral nonsteroidal anti-inflammatory drugs, foot orthotics, and stretching exercises can be tried for several weeks. In patients with chronic recalcitrant PF, extracorporeal shock wave therapy or corticosteroid injection can be considered. Surgery (minimally invasive techniques should be considered only after failure of the conservative treatments.Keywords: heel pain, surgery, plantar fasciosis

  7. Current Approaches in Cardio-Renal Syndrome

    Belguzar Kara

    2014-08-01

    Full Text Available In recent years, burden of cardiac and kidney diseases throughout the world is increasing. Studies show that the coexistence of both diseases contributes to increased mortality, morbidity, and healthcare costs. One of the major challenges facing health systems today is to prevent cardio-renal syndrome and provide quality health services to individuals with cardio-renal syndrome. The and #8220;cardio-renal syndrome and #8221; is a general term to describe different clinical conditions in which heart and kidney dysfunctions coexist. Although the incidence of cardio-renal syndrome is increasing, the evidences are limited about its pathophysiology and effective management. Severe problems may occur due to the interaction of neurohumoral, hemodynamic, and other less known factors in patients with cardio-renal syndrome. Therefore, the management of cardio-renal syndrome requires a multidisciplinary, mutifaceted and patient-centred approach. The most recent developments on the definition, classification, epidemiology, pathophysiology, and prevention and management strategies of cardio-renal syndrome are discussed in this revie. [TAF Prev Med Bull 2014; 13(4.000: 335-344

  8. CURRENT APPROACHES TO CHEMORADIOTHERAPY FOR MALIGNANT GLIOMAS

    Ye. L. Choinzonov

    2014-01-01

    Full Text Available High-grade malignant gliomas (WHO grade G III–IV account for more than 50% of all primary brain tumors. Despite aggressive treatment, survival rates are still very low with a median reported survival of no more than 1.5 years.Radiation therapy is an integral part of the combined treatment, but often does not influence lethally on resistant tumor cells. Thereby, in recent decades there has been an active search for novel approaches to the treatment of malignant gliomas (chemotherapeutic drugs, biological modifiers, local hyperthermia. Experimental data showed that the effect of high temperatures has both a direct damaging effect on tumor cells and a sensitizing effect. Significant advantages are achieved when the complex treatment of different malignant tumorsincludes local hyperthermia. However data on the treatment of patients with primary and recurrent gliomas G III–IV using local hyperthermia are scarce.The literature review is given in the article provides an overview of the existing treatment methods for brain tumors.

  9. Pulp Regeneration: Current Approaches and Future Challenges

    Yang, Jingwen; Yuan, Guohua; Chen, Zhi

    2016-01-01

    Regenerative endodontics aims to replace inflamed/necrotic pulp tissues with regenerated pulp-like tissues to revitalize teeth and improve life quality. Pulp revascularization case reports, which showed successful clinical and radiographic outcomes, indicated the possible clinical application of pulp regeneration via cell homing strategy. From a clinical point of view, functional pulp-like tissues should be regenerated with the characterization of vascularization, re-innervation, and dentin deposition with a regulated rate similar to that of normal pulp. Efficient root canal disinfection and proper size of the apical foramen are the two requisite preconditions for pulp regeneration. Progress has been made on pulp regeneration via cell homing strategies. This review focused on the requisite preconditions and cell homing strategies for pulp regeneration. In addition to the traditionally used mechanical preparation and irrigation, antibiotics, irrigation assisted with EndoVac apical negative-pressure system, and ultrasonic and laser irradiation are now being used in root canal disinfection. In addition, pulp-like tissues could be formed with the apical foramen less than 1 mm, although more studies are needed to determine the appropriate size. Moreover, signaling molecules including stromal cell derived factor (SDF-1α), basic Fibroblast Growth Factor (bFGF), Platelet Derived Growth Factor (PDGF), stem cell factor (SCF), and Granulocyte Colony-Stimulating Factor (G-CSF) were used to achieve pulp-like tissue formation via a cell homing strategy. Studies on the cell sources of pulp regeneration might give some indications on the signaling molecular selection. The active recruitment of endogenous cells into root canals to regenerate pulp-like tissues is a novel concept that may offer an unprecedented opportunity for the near-term clinical translation of current biology-based therapies for dental pulp regeneration. PMID:27014076

  10. Optimization of Charging Current and SOH Estimation for Lead Acid Batteries

    Amin Rezaei Pish Robat

    2012-02-01

    Full Text Available In this paper a new model-based approach is used to optimize the charging current of lead acid batteries for use in hybrid electric. The used model is a dynamical nonlinear model and so steepest descent, as a nonlinear optimization technique, is used to design the desired current profile. To verify the results, Unscented Kalman Filter is used to estimate battery capacity as a criterion of the state of health of the battery. Simulation results show that in comparison with multi level charging current, the proposed approach improves the state of health of the battery, up to 2.5% in the first 100 charge/discharge cycle

  11. Microbial production of hyaluronic acid: current state, challenges, and perspectives

    Liu Long

    2011-11-01

    Full Text Available Abstract Hyaluronic acid (HA is a natural and linear polymer composed of repeating disaccharide units of β-1, 3-N-acetyl glucosamine and β-1, 4-glucuronic acid with a molecular weight up to 6 million Daltons. With excellent viscoelasticity, high moisture retention capacity, and high biocompatibility, HA finds a wide-range of applications in medicine, cosmetics, and nutraceuticals. Traditionally HA was extracted from rooster combs, and now it is mainly produced via streptococcal fermentation. Recently the production of HA via recombinant systems has received increasing interest due to the avoidance of potential toxins. This work summarizes the research history and current commercial market of HA, and then deeply analyzes the current state of microbial production of HA by Streptococcus zooepidemicus and recombinant systems, and finally discusses the challenges facing microbial HA production and proposes several research outlines to meet the challenges.

  12. Lanthanides separation by counter - current electrophoretic using α - hydroxyisobutyric acid

    Studies about counter-current electrophoretic separation of rare earth metal ions using α-hydroxyisobutyric acid as complexing electrolyte are discussed. La, Pr, Nd, Sm and Eu were separated and fractions with purities better than 99,9% were obtained, using neutron activation analysis. A relation between the first stability constant of the α-hydroxyisobutyrate/lanthanide complexes and their migration velocities were observed. (M.J.C.)

  13. Bio-production of lactobionic acid: current status, applications and future prospects.

    Alonso, Saúl; Rendueles, Manuel; Díaz, Mario

    2013-12-01

    Lactobionic acid has appeared on the commercial scene as a versatile polyhydroxy acid with numerous promising applications in the food, medicine, pharmaceutical, cosmetics and chemical industries. This high value-added bio-product has recently received growing attention as a bioactive compound, providing an excellent chemical platform for the synthesis of novel potentially biocompatible and biodegradable drug delivery vehicles. Recent advances in tissue engineering and nanomedicine have also underlined the increased importance of this organic acid as a key biofunctionalization agent. The growing commercial relevance of lactobionic acid has therefore prompted the development of novel systems for its biotechnological production that are both sustainable and efficient. The present review explores recent advances and studies related to lactobionic acid bio-production, whether through microbial or enzymatic approaches, highlighting the key bioprocessing conditions for enhanced bio-production. Detailed overviews of the current microbial cell factories as well as downstream processing methodologies for lactobionic acid production are also presented. Furthermore, the potential prospects and current applications of this polyhydroxy acid are also discussed, with an emphasis on the role of lactobionic acid as a key platform in the development of novel drugs, biomaterials, nanoparticles and biopolymer systems. PMID:23651661

  14. A new approach to the direct digitization of low current

    The operation of a new current digitizer circuit is described in detail. With its direct but simple approach, the accuracy of measurement of low dc has been improved. At an input current 30 nA, the standard deviation was 0.07 per cent of the mean. With its wide linear response from pico to milli ampere and direct compatability to all types of current sources including photomultipliers, its potential uses and applications are discussed. (author). 9 refs., 5 figs

  15. Current taxonomy of phages infecting lactic acid bacteria

    Jennifer eMahony

    2014-01-01

    Full Text Available Phages infecting lactic acid bacteria have been the focus of significant research attention over the past three decades. Through the isolation and characterization of hundreds of phage isolates, it has been possible to classify phages of the dairy starter and adjunct bacteria Lactococus lactis, Streptococcus thermophilus, Leuconostoc spp. and Lactobacillus spp. Among these, phages of L. lactis have been most thoroughly scrutinized and serve as an excellent model system to address issues that arise when attempting taxonomic classification of phages infecting other LAB species. Here, we present an overview of the current taxonomy of phages infecting LAB genera of industrial significance, the methods employed in these taxonomic efforts and how these may be employed for the taxonomy of phages of currently underrepresented and emerging phage species.

  16. Multiplexed microfluidic approach for nucleic acid enrichment

    VanderNoot, Victoria A.; Langevin, Stanley Alan; Bent, Zachary; Renzi, Ronald F.; Ferko, Scott M.; Van De Vreugde, James L.; Lane, Todd; Patel, Kamlesh; Branda, Steven

    2016-04-26

    A system for enhancing a nucleic acid sample may include a one pump, a denaturing chamber; a microfluidic hydroxyapatite chromatography device configured for performing hydroxyapatite chromatography on the nucleic acid sample, a sample collector, and tubing connecting the pump with the denaturing chamber, the hydroxyapatite chromatography device and the sample collector such that the pump may be used to move the nucleic acid sample from the denaturing chamber to the hydroxyapatite chromatography device and then to the sample collector.

  17. Rheological evaluation of simulated neutralized current acid waste

    A byproduct of the Purex process is an aqueous waste stream that contains fission products. This waste stream, called current acid waste, is chemically neutralized and stored in double shell tanks on the Hanford Site. This neutralized current acid waste (NCAW) will be transported by pipe to B-Plant, a processing plant on the Hanford Site. Rheological and transport properties of NCAW slurry were evaluated. First, researchers conducted lab rheological evaluations of simulated NCAW. The results of these evaluations were then correlated with classical rheological models and scaled up to predict the performance that is likely to occur in the full-scale system. The NCAW in the tank will either be retrieved as is, i.e., no change in the concentration presently in the tank, or will be slightly concentrated before retrieval. Sluicing may be required to retrieve the solids. Three concentrations of simulated NCAW were evaluated that would simulate the different retrieval options: NCAW in the concentration that is presently in the tank; a slightly concentrated NCAW, called NCAW5.5; and equal parts of NCAW settled solids and water (simulating the sluicing stage), called NCAW1:1. The physical and rheological properties of three samples of each concentration at 25 and 1000C were evaluated in the laboratory. The properties displayed by NCAW and NCAW5.5 at 25 and 1000C allowed it to be classified as a pseudoplastic non-Newtonian fluid. NCAW1:1 at 25 and 1000C displayed properties of a yield-pseudoplastic non-Newtonian fluid. The classical non-Newtonian models for pseudoplastic and yield-pseudoplastic fluids were used with the laboratory data to predict the full-scale pump-pipe network parameters

  18. Rheological evaluation of simulated neutralized current acid waste - transuranics

    At the Hanford Plutonium and Uranium Extraction Plant (PUREX), in Richland, Washington, plutonium and uranium products are recovered from irradiated fuel by a solvent extraction process. A byproduct of this process is an aqueous waste stream that contains fission products. This waste stream, called current acid waste (CAW), is chemically neutralized and stored in double shell tanks (DSTs) on the Hanford Site. This neutralized current acid waste (NCAW) will be transported by pipe to B-Plant, a processing plant located nearby. In B-Plant, the transuranic (TRU) elements in NCAW are separated from the non-TRU elements. The majority of the TRU elements in NCAW are in the solids. Therefore, the primary processing operation is to separate the NCAW solids (NCAW-TRU) from the NCAW liquid. These two waste streams will be pumped to suitable holding tanks before being further processed for permanent disposal. To ensure that the retrieval and transportation of NCAW and NCAW-TRU are successful, researchers at Pacific Northwest Laboratory (PNL) evaluated the rheological and transport properties of the slurries. This evaluation had two phases. First, researchers conducted laboratory rheological evaluations of simulated NCAW and NCAW-TRU. The results of these evaluations were then correlated with classical rheological models and scaled up to predict the performance that is likely to occur in the full-scale system. This scale-up procedure has already been successfully used to predict the critical transport properties of a slurry (Neutralized Cladding Removal Waste) with rheological properties similar to those displayed by NCAW and NCAW-TRU

  19. Taxation of Fringe Benefits: Alternative Approaches to Current Problems.

    Cohen, Anita E.

    1979-01-01

    The current IRS tax treatment of fringe benefits is seen as inadequate, and the judicial precept confusing, because groups of employee benefits are inappropriately excluded from taxation as perquisites. A tax equalization approach is proposed. Available from Suffolk University Law Review Office, 41 Temple St., Boston, MA 02114. (MSE)

  20. Fatty acid and vitamin interventions in adults with schizophrenia: a systematic review of the current evidence.

    Chia, Siok Ching; Henry, Jeyakumar; Mok, Yee Ming; Honer, William G; Sim, Kang

    2015-12-01

    Current psychopharmacological approaches to reduce psychotic phenomenology in schizophrenia are associated with adverse effects including extrapyramidal and metabolic side effects. In view of the emerging data on nutritional supplementation interventions in schizophrenia which are not entirely consistent, we aimed to review existent studies focusing on fatty acid and vitamin interventions and summarise current evidence on such nutritional supplementations in schizophrenia. We searched the digital databases (ScienceDirect, Scopus, SpringerLINK, PubMed/Medline) for relevant studies pertaining to fatty acid and vitamin supplementation interventions in the management of psychotic symptoms in schizophrenia up to February 2015. Overall, there were more studies conducted on fatty acid over vitamin supplementations in patients with schizophrenia. There were more positive findings in support of fatty acid supplementation compared with vitamin supplementation in the context of specific intervention features (dose of nutrient supplementation, single versus combination nutritional interventions, specific antipsychotic), subject features (older age, long duration of illness, baseline polyunsaturated fatty acid levels) and clinical outcomes (improvements of psychotic symptoms and/or extrapyramidal side effects from antipsychotics). However, investigations of both supplementation modalities were limited by relatively small study sample sizes, short study duration, which precluded further segmentation of impact on more diverse patient subtypes and symptom profiles. Future studies may consider examining larger samples over a longer time period, recruiting younger subjects with shorter duration of illness, examination of different clinical features including specific cognitive domains, and use of single versus combination nutritional interventions. PMID:26354100

  1. Current and future developments in nucleic acid-based diagnostics

    The detection and characterization of specific nucleic acids of protozoa, rickettsia, bacteria and viruses have proven to be particularly useful for detecting pathogens of human and veterinary importance. It is also proving an invaluable tool for surveillance purposes and as a means of ensuring food security. Previous approaches towards pathogen isolation have often been tedious or even impossible. PCR, first conceived by Mullis in 1983, has proven to be a revolutionary technique for the rapid and accurate detection of numerous pathogens. The discovery and cloning of thermostable DNA polymerases has further contributed to this technology. Many additional developments, based on the basic principles of PCR, have been described e.g. RT-PCR, NASBA, RAPD, AFLP, LCR, PCR ELISA, strand displacement amplification (SDA), transcription-mediated amplification (TMA), branched DNA (bDNA), hybrid capture, immunocapture PCR. This list continues to expand with new variations on basic PCR principles. Improvements in thermocyclers involve the development of integrated amplification and signal detection systems, including on-line real-time devices. In addition, rugged portable instruments have been designed for field use. These are particularly useful as systems for early warning in detecting biowarfare agents and outbreaks of cross-boundary and other pathogens. Fluorophores, utilising principles of fluorescence resonance energy transfer, are used as labels for probes in such real-time assays. Molecular beacon technology also utilises such mechanisms. Real-time thermocyclers allow the monitoring of amplified DNA as well as establishing sequence characteristics based on melting or hybridisation curves. Taqman chemistry makes use of such a system. Stem-loop DNA probes have been designed to have increased specificity for target recognition and include molecular beacon methodologies, suppression PCR approaches and hairpin probes in DNA microarrays. Automated sample processing or robotic

  2. Current Therapeutic Strategies and Novel Approaches in Osteosarcoma

    Ando, Kosei; Heymann, Marie-Françoise; Stresing, Verena; Mori, Kanji; Rédini, Françoise; Heymann, Dominique

    2013-01-01

    Osteosarcoma is the most frequent malignant primary bone tumor and a main cause of cancer-related death in children and adolescents. Although long-term survival in localized osteosarcoma has improved to about 60% during the 1960s and 1970s, long-term survival in both localized and metastatic osteosarcoma has stagnated in the past several decades. Thus, current conventional therapy consists of multi-agent chemotherapy, surgery and radiation, which is not fully adequate for osteosarcoma treatment. Innovative drugs and approaches are needed to further improve outcome in osteosarcoma patients. This review describes the current management of osteosarcoma as well as potential new therapies. PMID:24216993

  3. Ant Colony Approach to Predict Amino Acid Interaction Networks

    Gaci, Omar; Balev, Stefan

    2009-01-01

    In this paper we introduce the notion of protein interaction network. This is a graph whose vertices are the proteins amino acids and whose edges are the interactions between them. We consider the problem of reconstructing protein's interaction network from its amino acid sequence. An ant colony approach is used to solve this problem.

  4. Current and future immunotherapeutic approaches in Hodgkin lymphoma.

    Bröckelmann, Paul J; Borchmann, Peter; Engert, Andreas

    2016-09-01

    Hodgkin lymphoma (HL) has become a highly curable malignancy even in advanced stages when treated adequately. However, relapsed or refractory disease and treatment-related toxicity constitute a significant clinical challenge. Innovative approaches are thus needed to improve treatment of these mainly young patients. In HL lesions, very few malignant Hodgkin and Reed-Sternberg (HRS) cells are embedded in an immunosuppressive microenvironment of reactive cells. Novel approaches such as bispecific antibodies, antibody-drug conjugates, immune-checkpoint inhibitors or adoptive cellular therapies are currently being investigated with promising results in relapsed or refractory patients. Encouraging response rates and a favorable toxicity profile have recently been reported in early phase clinical trials with antibodies blocking the programed-death receptor 1 (PD1). This review will summarize the current clinical knowledge on mechanism, safety and efficacy of the different agents and discuss potential future strategies, which are partly already investigated within clinical trials. PMID:27243940

  5. Current treatment approach to non-clear cell renal carcinoma

    I. V. Tsimafeyeu

    2015-01-01

    Non-clear cell renal cell carcinoma has various histologic subtypes. Tumor biology plays significant role in the disease development. However, despite the one surgical approach both to clear cell and non-clear cell renal carcinoma, patients’ outcomes within one stage of the disease may vary. Furthermore, tumor sensitivity and its response to therapy are highly dependent on the same histologic subtype.The article gives detailed data on the current treatment of papillary, chromophobe and other ...

  6. Glycolic acid peel therapy – a current review

    Sharad, Jaishree

    2013-01-01

    Jaishree Sharad Skinfiniti Aesthetic Skin and Laser Clinic, Mumbai, India Abstract: Chemical peels have been time-tested and are here to stay. Alpha-hydroxy peels are highly popular in the dermatologist's arsenal of procedures. Glycolic acid peel is the most common alpha-hydroxy acid peel, also known as fruit peel. It is simple, inexpensive, and has no downtime. This review talks about various studies of glycolic acid peels for various indications, such as acne, acne scars, melasma, ...

  7. Glycolic acid peel therapy – a current review

    Sharad J

    2013-01-01

    Jaishree Sharad Skinfiniti Aesthetic Skin and Laser Clinic, Mumbai, India Abstract: Chemical peels have been time-tested and are here to stay. Alpha-hydroxy peels are highly popular in the dermatologist's arsenal of procedures. Glycolic acid peel is the most common alpha-hydroxy acid peel, also known as fruit peel. It is simple, inexpensive, and has no downtime. This review talks about various studies of glycolic acid peels for various indications, such as acne, acne scars, melasma, posti...

  8. Optimizing nitrogen fertilizer use: Current approaches and simulation models

    Nitrogen (N) is the most common limiting nutrient in agricultural systems throughout the world. Crops need sufficient available N to achieve optimum yields and adequate grain-protein content. Consequently, sub-optimal rates of N fertilizers typically cause lower economical benefits for farmers. On the other hand, excessive N fertilizer use may result in environmental problems such as nitrate contamination of groundwater and emission of N2O and NO. In spite of the economical and environmental importance of good N fertilizer management, the development of optimum fertilizer recommendations is still a major challenge in most agricultural systems. This article reviews the approaches most commonly used for making N recommendations: expected yield level, soil testing and plant analysis (including quick tests). The paper introduces the application of simulation models that complement traditional approaches, and includes some examples of current applications in Africa and South America. (author)

  9. Respiratory sensitization and allergy: Current research approaches and needs

    There are currently no accepted regulatory models for assessing the potential of a substance to cause respiratory sensitization and allergy. In contrast, a number of models exist for the assessment of contact sensitization and allergic contact dermatitis (ACD). Research indicates that respiratory sensitizers may be identified through contact sensitization assays such as the local lymph node assay, although only a small subset of the compounds that yield positive results in these assays are actually respiratory sensitizers. Due to the increasing health concerns associated with occupational asthma and the impending directives on the regulation of respiratory sensitizers and allergens, an approach which can identify these compounds and distinguish them from contact sensitizers is required. This report discusses some of the important contrasts between respiratory allergy and ACD, and highlights several prominent in vivo, in vitro and in silico approaches that are being applied or could be further developed to identify compounds capable of causing respiratory allergy. Although a number of animal models have been used for researching respiratory sensitization and allergy, protocols and endpoints for these approaches are often inconsistent, costly and difficult to reproduce, thereby limiting meaningful comparisons of data between laboratories and development of a consensus approach. A number of emerging in vitro and in silico models show promise for use in the characterization of contact sensitization potential and should be further explored for their ability to identify and differentiate contact and respiratory sensitizers. Ultimately, the development of a consistent, accurate and cost-effective model will likely incorporate a number of these approaches and will require effective communication, collaboration and consensus among all stakeholders

  10. Current Approaches to the Establishment of Credit Risk Specific Provisions

    Ion Nitu

    2008-10-01

    Full Text Available The aim of the new Basel II and IFRS approaches is to make the operations of financial institutions more transparent and thus to create a better basis for the market participants and supervisory authorities to acquire information and make decisions. In the banking sector, a continuous debate is being led, related to the similarities and differences between IFRS approach on loan loss provisions and Basel II approach on calculating the capital requirements, judging against the classical method regarding loan provisions, currently used by the Romanian banks following the Central Bank’s regulations.Banks must take into consideration that IFRS and Basel II objectives are fundamentally different. While IFRS aims to ensure that the financial papers reflect adequately the losses recorded at each balance sheet date, the Basel II objective is to ensure that the bank has enough provisions or capital in order to face expected losses in the next 12 months and eventual unexpected losses.Consequently, there are clear differences between the objectives of the two models. Basel II works on statistical modeling of expected losses while IFRS, although allowing statistical models, requires a trigger event to have occurred before they can be used. IAS 39 specifically states that losses that are expected as a result of future events, no matter how likely, are not recognized. This is a clear and fundamental area of difference between the two frameworks.

  11. Glycolic acid peel therapy – a current review

    Sharad J

    2013-11-01

    Full Text Available Jaishree Sharad Skinfiniti Aesthetic Skin and Laser Clinic, Mumbai, India Abstract: Chemical peels have been time-tested and are here to stay. Alpha-hydroxy peels are highly popular in the dermatologist's arsenal of procedures. Glycolic acid peel is the most common alpha-hydroxy acid peel, also known as fruit peel. It is simple, inexpensive, and has no downtime. This review talks about various studies of glycolic acid peels for various indications, such as acne, acne scars, melasma, postinflammatory hyperpigmentation, photoaging, and seborrhea. Combination therapies and treatment procedure are also discussed. Careful review of medical history, examination of the skin, and pre-peel priming of skin are important before every peel. Proper patient selection, peel timing, and neutralization on-time will ensure good results, with no side effects. Depth of the glycolic acid peel depends on the concentration of the acid used, the number of coats applied, and the time for which it is applied. Hence, it can be used as a very superficial peel, or even a medium depth peel. It has been found to be very safe with Fitzpatrick skin types I–IV. All in all, it is a peel that is here to stay. Keywords: acne scar, melasma, photoaging, chemical peel, alpha-hydroxy peel

  12. Two complementary approaches to right-handed currents

    Flavour observables impose strong constraints on models of new physics. We study whether right-handed currents can provide a realistic extension to the Standard Model. We analyse two complementary models. These setups lead to new flavour violating interactions in the right-handed sector. We first consider a bottom-up approach assuming a left-right symmetric flavour group broken only by the Yukawa couplings. In this model the vertical stroke Vub vertical stroke problem can be solved. Secondly we study the Left-Right Model. We perform a comprehensive numerical analysis, including all known experimental constraints from ΔF=2 observables and the decay B →Xsγ simultaneously. We observe that there exist regions in parameter space in accordance with the all data. In this model all flavour anomalies can be resolved except the vertical stroke Vub vertical stroke problem.

  13. Invariant current approach to wave propagation in locally symmetric structures

    Zampetakis, V. E.; Diakonou, M. K.; Morfonios, C. V.; Kalozoumis, P. A.; Diakonos, F. K.; Schmelcher, P.

    2016-05-01

    A theory for wave mechanical systems with local inversion and translation symmetries is developed employing the two-dimensional solution space of the stationary Schrödinger equation. The local symmetries of the potential are encoded into corresponding local basis vectors in terms of symmetry-induced two-point invariant currents which map the basis amplitudes between symmetry-related points. A universal wavefunction structure in locally symmetric potentials is revealed, independently of the physical boundary conditions, by using special local bases which are adapted to the existing local symmetries. The local symmetry bases enable efficient computation of spatially resolved wave amplitudes in systems with arbitrary combinations of local inversion and translation symmetries. The approach opens the perspective of a flexible analysis and control of wave localization in structurally complex systems.

  14. Two complementary approaches to right-handed currents

    Gemmler, Katrin M.

    2012-04-17

    Flavour observables impose strong constraints on models of new physics. We study whether right-handed currents can provide a realistic extension to the Standard Model. We analyse two complementary models. These setups lead to new flavour violating interactions in the right-handed sector. We first consider a bottom-up approach assuming a left-right symmetric flavour group broken only by the Yukawa couplings. In this model the vertical stroke V{sub ub} vertical stroke problem can be solved. Secondly we study the Left-Right Model. We perform a comprehensive numerical analysis, including all known experimental constraints from {Delta}F=2 observables and the decay B {yields}X{sub s}{gamma} simultaneously. We observe that there exist regions in parameter space in accordance with the all data. In this model all flavour anomalies can be resolved except the vertical stroke V{sub ub} vertical stroke problem.

  15. Approaches to overcome current limitations of HIFU treatment

    Umemura, Shin-Ichiro; Kawabata, Ken-Ichi; Sasaki, Kazuaki; Azuma, Takashi; Ishida, Kazunari; Kubota, Jun; Ichihara, Mitsuyoshi; Okai, Takashi

    2001-05-01

    Noninvasive therapy with HIFU has been successfully applied to transrectal treatment of prostate cancer as well as benign prostate hyperplasia. However, there are two major technical reasons why its clinical application to other organs is currently limited: (1) low throughput of treatment and (2) lack of penetration to deep tissues. To multiply the throughput, a split-focus technique, in which the focal spot is enlarged primarily in the lateral direction, was developed. An electronically variable focus array transducer was also developed to enhance the throughput. An approach to treat a large volume of uterus myoma by coagulating its feeding arteries has been studied. The tissue volume to be coagulated can be thereby reduced by orders of magnitude. The penetration and throughput can potentially be improved at the same time by delivering a microbubble agent to the target tissue. It was theoretically predicted that a microbubble agent could multiply the ultrasonic tissue absorption. The effectiveness of this approach was confirmed in animal experiments using Optison. Real-time monitoring of tissue coagulation during HIFU exposure also can enhance the throughput through preventing excess deposition of ultrasonic energy. Monitoring coagulation by imaging local displacement in tissue with ultrasound will be discussed as well.

  16. Public Economy versus Planned Economy. Current Approaches and Problems

    Ani Matei

    2006-03-01

    Full Text Available he present paper proposes a review of the current object and problems facing the public economy. For the past decade and a half, public economy has clearly come back in the attention of the research interests of specialists from the Central and Eastern European countries. Among these, the scientific research encompassed by the public economy area interrelates with the international trends. At a closer look, public economy appears to be a science, particularly interdisciplinary, with sociological, political, econometrical or systemic approaches possible to prevail. To continue, the author makes reference to four pillars of the public economy: optimum, welfare, social choice and economic justice that allow different approaches to develop. A science branch, equally theoretical and practical, public economy will stress its connections with the economic and mathematic modeling, systemic analysis or sociological and political research. Still, seve¬ral problems in public economy remain open. These concentrate on the public interest, intervention and decision. Conceptualization, understanding and description of the mechanisms that allow the operationalisation may form the basis for further developments on both theoretical and practical level. A clear distinction in order to justify the title of this article needs to be made. Public economy is not to be confused with planning economy. The state remains but one of the producers and delivery agents of public goods and services.

  17. Current Opinion on the Oncoplastic Approach in the USA.

    Losken, Albert; Kapadia, Sameer; Egro, Francesco M; Baecher, Kirsten M; Styblo, Toncred M; Carlson, Grant W

    2016-07-01

    The management of women with breast cancer who wish to preserve their breasts often includes partial reconstruction at the time of tumor resection. This is referred to as the oncoplastic approach and has been shown to improve outcomes. The purpose of this review was to better understand the current surgeon mindset relative to the oncoplastic approach. A survey was designed to understand demographics and opinions on partial breast reconstruction at the time of tumor resection. This was disseminated to the registered members of the American Society of Breast Surgeons as well the American Society of Plastic Surgeons (ASPS) through an online system and comparisons were made. There were 422 responders in the ABS and 214 responders in the ASPS for a response rate of 14.8% and 9.1%, respectively. Most (69.7%) breast surgeons felt that partial breast reconstruction following lumpectomy was not limited in their practice. Fifty percent of plastic surgeons felt that it was limited because they were not getting the referrals. Both groups agreed that complex partial reconstructions were best performed using the team approach. Margin involvement was a major concern in both groups, and the groups agreed that the aesthetic benefits were a major driving force. Future adoption of these techniques will rely on increased training and increased awareness of these procedures. There tends to be general agreement surrounding the concerns and benefits of immediately reconstructing the partial mastectomy defect. Disparity does exist between the two groups in terms of delivery likely due to the system-based inadequacies in the USA. This represents an area for improvement. PMID:27060905

  18. Acid-base analysis: a critique of the Stewart and bicarbonate-centered approaches.

    Kurtz, Ira; Kraut, Jeffrey; Ornekian, Vahram; Nguyen, Minhtri K

    2008-05-01

    When approaching the analysis of disorders of acid-base balance, physical chemists, physiologists, and clinicians, tend to focus on different aspects of the relevant phenomenology. The physical chemist focuses on a quantitative understanding of proton hydration and aqueous proton transfer reactions that alter the acidity of a given solution. The physiologist focuses on molecular, cellular, and whole organ transport processes that modulate the acidity of a given body fluid compartment. The clinician emphasizes the diagnosis, clinical causes, and most appropriate treatment of acid-base disturbances. Historically, two different conceptual frameworks have evolved among clinicians and physiologists for interpreting acid-base phenomena. The traditional or bicarbonate-centered framework relies quantitatively on the Henderson-Hasselbalch equation, whereas the Stewart or strong ion approach utilizes either the original Stewart equation or its simplified version derived by Constable. In this review, the concepts underlying the bicarbonate-centered and Stewart formulations are analyzed in detail, emphasizing the differences in how each approach characterizes acid-base phenomenology at the molecular level, tissue level, and in the clinical realm. A quantitative comparison of the equations that are currently used in the literature to calculate H(+) concentration ([H(+)]) is included to clear up some of the misconceptions that currently exist in this area. Our analysis demonstrates that while the principle of electroneutrality plays a central role in the strong ion formulation, electroneutrality mechanistically does not dictate a specific [H(+)], and the strong ion and bicarbonate-centered approaches are quantitatively identical even in the presence of nonbicarbonate buffers. Finally, our analysis indicates that the bicarbonate-centered approach utilizing the Henderson-Hasselbalch equation is a mechanistic formulation that reflects the underlying acid-base phenomenology. PMID

  19. Current Perspectives on Desmoid Tumors: The Mayo Clinic Approach

    Desmoid tumors are a rare group of locally aggressive, non malignant tumors of fibroblastic origin that can lead to significant morbidity due to local invasion. Despite advances in the understanding of these tumors, their natural history is incompletely understood and the optimal treatment is still a matter of debate. Local control is the main goal of treatment and there has been a change in philosophy regarding the management of these tumors from aggressive surgical resection to function preservation. A multidisciplinary approach is essential to plan local control with acceptable morbidity. The current Mayo Clinic algorithm for the treatment of these tumors is based on institutional experience and the available evidence in the literature: asymptomatic/non progressive lesions away from vital structures are managed with observation and regular imaging; primary or recurrent desmoid tumors which are symptomatic or progressive or near vital structures are managed with wide surgical resection when wide surgical margins are possible with minimal functional and cosmetic loss. When positive or close surgical margins are likely, surgical resection with adjuvant radiotherapy or definitive radiotherapy is preferred. If likely functional or cosmetic deficit is unacceptable, radiotherapy is the treatment of choice. Unresectable lesions are considered for radiotherapy, chemotherapy or newer modalities however an unresectable lesion associated with a painful, functionless, infected extremity is managed with an amputation

  20. Current Perspectives on Desmoid Tumors: The Mayo Clinic Approach

    Scott Okuno

    2011-08-01

    Full Text Available Desmoid tumors are a rare group of locally aggressive, non malignant tumors of fibroblastic origin that can lead to significant morbidity due to local invasion. Despite advances in the understanding of these tumors, their natural history is incompletely understood and the optimal treatment is still a matter of debate. Local control is the main goal of treatment and there has been a change in philosophy regarding the management of these tumors from aggressive surgical resection to function preservation. A multidisciplinary approach is essential to plan local control with acceptable morbidity. The current Mayo Clinic algorithm for the treatment of these tumors is based on institutional experience and the available evidence in the literature: asymptomatic/non progressive lesions away from vital structures are managed with observation and regular imaging; primary or recurrent desmoid tumors which are symptomatic or progressive or near vital structures are managed with wide surgical resection when wide surgical margins are possible with minimal functional and cosmetic loss. When positive or close surgical margins are likely, surgical resection with adjuvant radiotherapy or definitive radiotherapy is preferred. If likely functional or cosmetic deficit is unacceptable, radiotherapy is the treatment of choice. Unresectable lesions are considered for radiotherapy, chemotherapy or newer modalities however an unresectable lesion associated with a painful, functionless, infected extremity is managed with an amputation.

  1. Current Perspectives on Desmoid Tumors: The Mayo Clinic Approach

    Joglekar, Siddharth B. [Musculoskeletal Oncology, Mayo Clinic, Rochester, MN55905 (United States); Rose, Peter S.; Sim, Franklin, E-mail: sim.franklin@mayo.edu [Department of Orthopedics, Mayo Clinic, 200 1st ST SW, Rochester, MN 55905 (United States); Okuno, Scott [Department of Oncology, Mayo Clinic, Rochester, MN55905 (United States); Petersen, Ivy [Department of Radiation Oncology, Mayo Clinic, Rochester, MN55905 (United States)

    2011-08-08

    Desmoid tumors are a rare group of locally aggressive, non malignant tumors of fibroblastic origin that can lead to significant morbidity due to local invasion. Despite advances in the understanding of these tumors, their natural history is incompletely understood and the optimal treatment is still a matter of debate. Local control is the main goal of treatment and there has been a change in philosophy regarding the management of these tumors from aggressive surgical resection to function preservation. A multidisciplinary approach is essential to plan local control with acceptable morbidity. The current Mayo Clinic algorithm for the treatment of these tumors is based on institutional experience and the available evidence in the literature: asymptomatic/non progressive lesions away from vital structures are managed with observation and regular imaging; primary or recurrent desmoid tumors which are symptomatic or progressive or near vital structures are managed with wide surgical resection when wide surgical margins are possible with minimal functional and cosmetic loss. When positive or close surgical margins are likely, surgical resection with adjuvant radiotherapy or definitive radiotherapy is preferred. If likely functional or cosmetic deficit is unacceptable, radiotherapy is the treatment of choice. Unresectable lesions are considered for radiotherapy, chemotherapy or newer modalities however an unresectable lesion associated with a painful, functionless, infected extremity is managed with an amputation.

  2. Current sheet oscillations in the magnetic filament approach

    Erkaev, N. V. [Institute of Computational Modelling, Russian Academy of Sciences, Krasnoyarsk (Russian Federation); Siberian Federal University, Krasnoyarsk (Russian Federation); Semenov, V. S. [Institute of Physics, State University of St. Petersburg, St. Petersburg (Russian Federation); Biernat, H. K. [Space Research Institute, Austrian Academy of Sciences, Graz (Austria); Institute of Physics, University of Graz, Graz (Austria)

    2012-06-15

    Magnetic filament approach is applied for modeling of nonlinear 'kink'-like flapping oscillations of thin magnetic flux tubes in the Earth's magnetotail current sheet. A discrete approximation for the magnetic flux tube was derived on a basis of the Hamiltonian formulation of the problem. The obtained system of ordinary differential equations was integrated by method of Rosenbrock, which is suitable for stiff equations. The two-dimensional exact Kan's solution of the Vlasov equations was used to set the background equilibrium conditions for magnetic field and plasma. Boundary conditions for the magnetic filament were found to be dependent on the ratio of the ionospheric conductivity and the Alfven conductivity of the magnetic tube. It was shown that an enhancement of this ratio leads to the corresponding increase of the frequency of the flapping oscillations. For some special case of boundary conditions, when the magnetic perturbations vanish at the boundaries, the calculated frequency of the 'kink'-like flapping oscillations is rather close to that predicted by the 'double gradient' analytical model. For others cases, the obtained frequency of the flapping oscillations is somewhat larger than that from the 'double gradient' theory. The frequency of the nonlinear flapping oscillations was found to be a decreasing function of the amplitude.

  3. Current and future developments in nucleic acid-based diagnostics

    The detection and characterization of specific nucleic acids of medico-veterinary pathogens have proven invaluable for diagnostic purposes. Apart from hybridization and sequencing techniques, polymerase chain reaction (PCR) and numerous other methods have contributed significantly to this process. The integration of amplification and signal detection systems, including on-line real-time devices, have increased speed and sensitivity and greatly facilitated the quantification of target nucleic acids. They have also allowed for sequence characterization using melting or hybridization curves. Rugged portable real-time instruments for field use and robotic devices for processing samples are already available commercially. Various stem-loop DNA probes have been designed to have greater specificity for target recognition during real-time PCR. Various DNA fingerprinting techniques or post amplification sequencing are used to type pathogenic strains. Characterization according to DNA sequence is becoming more readily available as automated sequencers become more widely used. Reverse hybridization and to a greater degree DNA micro-arrays, are being used for genotyping related organisms and can allow for the detection of a large variety of different pathogens simultaneously. Non-radioactive labelling of DNA, especially using fluorophores and the principles of fluorescence resonance energy transfer, is now widely used, especially in real-time detection devices. Other detection methods include the use of surface plasmon resonance and MALDI-TOF mass spectrometry. In addition to these technological advances, contributions by bioinformatics and the description of unique signatures of DNA sequences from pathogens will contribute to the development of further assays for monitoring presence of pathogens. An important goal will be the development of robust devices capable of sensitively and specifically detecting a broad spectrum of pathogens that will be applicable for point

  4. Nucleic acid-based approaches to STAT inhibition.

    Sen, Malabika; Grandis, Jennifer R

    2012-10-01

    Silencing of abnormally activated genes can be accomplished in a highly specific manner using nucleic acid based approaches. The focus of this review includes the different nucleic acid based inhibition strategies such as antisense oligodeoxynucleotides, small interfering RNA (siRNA), dominant-negative constructs, G-quartet oligonucleotides and decoy oligonucleotides, their mechanism of action and the effectiveness of these approaches to targeting the STAT (signal transducer and activator of transcription) proteins in cancer. Among the STAT proteins, especially STAT3, followed by STAT5, are the most frequently activated oncogenic STATs, which have emerged as plausible therapeutic cancer targets. Both STAT3 and STAT5 have been shown to regulate numerous oncogenic signaling pathways including proliferation, survival, angiogenesis and migration/invasion. PMID:24058785

  5. Current approaches to nuclear power plant life management in Japan

    extracted additional maintenance measures and incorporated them into their long-term maintenance plans, thereby reinforcing their current maintenance activities. Considering the latest information including domestic and overseas operating experiences and knowledge of academics and experts consigned by the Minister of Economy, Trade and Industry (METI), the Nuclear and Industry Safety Agency (NISA) of the METI reviewed and studied the technical evaluation and long-term maintenance plans of these electric utility companies. This paper describes the outlines of the NISA's report and related activities on current approaches to cope with the ageing of nuclear power plants in Japan. (Note) In 2001, the MITI was reorganized to the Ministry of Economy, Trade and Industry (METI). (author)

  6. Current approaches to electrospun nanofibers for tissue engineering

    The ultimate goal of tissue engineering is to replace damaged tissues by applying engineering technology and the principles of life sciences. To successfully engineer a desirable tissue, three main elements of cells, scaffolds and growth factors need to be harmonized. Biomaterial-based scaffolds serve as a critical platform both to support cell adhesion and to deliver growth factors. Various methods of fabricating scaffolds have been investigated. One recently developed method that is growing in popularity is called electrospinning. Electrospinning is known for its capacity to make fibrous and porous structures that are similar to natural extracellular matrix (ECM). Other advantages to electrospinning include its ability to create relatively large surface to volume ratios, its ability to control fiber size from micro- to nano-scales and its versatility in material choice. Although early work with electrospun fibers has shown promise in the regeneration of certain types of tissues, further modification of their chemical, biological and mechanical properties would permit future advancements. In this paper, current approaches to the development of modular electrospun fibers as scaffolds for tissue engineering are discussed. Their chemical and physical characteristics can be tuned for the regeneration of specific target tissues by co-spinning of multiple materials and by post-modification of the surface of electrospun fibers. In addition, topology or structure can also be controlled to elicit specific responses from cells and tissues. The selection of proper polymers, suitable surface modification techniques and the control of the dimension and arrangement of the fibrous structure of electrospun fibers can offer versatility and tissue specificity, and therefore provide a blueprint for specific tissue engineering applications. (paper)

  7. Mefenamic acid bi-directionally modulates the transient outward K+ current in rat cerebellar granule cells

    The effect of non-steroidal anti-inflammatory drugs (NSAIDs) on ion channels has been widely studied in several cell models, but less is known about their modulatory mechanisms. In this report, the effect of mefenamic acid on voltage-activated transient outward K+ current (IA) in cultured rat cerebellar granule cells was investigated. At a concentration of 5 μM to 100 μM, mefenamic acid reversibly inhibited IA in a dose-dependent manner. However, mefenamic acid at a concentration of 1 μM significantly increased the amplitude of IA to 113 ± 1.5% of the control. At more than 10 μM, mefenamic acid inhibited the amplitude of IA without any effect on activation or inactivation. In addition, a higher concentration of mefenamic acid induced a significant acceleration of recovery from inactivation with an increase of the peak amplitude elicited by the second test pulse. Intracellular application of mefenamic acid could significantly increase the amplitude of IA, but had no effect on the inhibition induced by extracellular mefenamic acid, implying that mefenamic acid may exert its effect from both inside and outside the ion channel. Furthermore, the activation of current induced by intracellular application of mefenamic acid was mimicked by other cyclooxygenase inhibitors and arachidonic acid. Our data demonstrate that mefenamic acid is able to bi-directionally modulate IA channels in neurons at different concentrations and by different methods of application, and two different mechanisms may be involved

  8. Current Approaches to the Establishment of Credit Risk Specific Provisions

    Ion Nitu; Alin Eduard Nitu; Eliza Paicu

    2008-01-01

    The aim of the new Basel II and IFRS approaches is to make the operations of financial institutions more transparent and thus to create a better basis for the market participants and supervisory authorities to acquire information and make decisions. In the banking sector, a continuous debate is being led, related to the similarities and differences between IFRS approach on loan loss provisions and Basel II approach on calculating the capital requirements, judging against the classical method ...

  9. MELiSSA Food Characterization general approach and current status

    Weihreter, Martin; Chaerle, Laury; Secco, Benjamin; Molders, Katrien; van der Straeten, Dominique; Duliere, Eric; Pieters, Serge; Maclean, Heather; Dochain, Denis; Quinet, Muriel; Lutts, Stanley; Graham, Thomas; Stasiak, Michael; Rondeau Vuk, Theresa; Zheng, Youbin; Dixon, Mike; Laniau, Martine; Larreture, Alain; Timsit, Michel; Aronne, Giovanna; Barbieri, Giancarlo; Buonomo, Roberta; Veronica; Paradiso, Roberta; de Pascale, Stafania; Galbiati, Massimo; Troia, A. R.; Nobili, Matteo; Bucchieri, Lorenzo; Page, Valérie; Feller, Urs; Lasseur, Christophe

    . Available MELiSSA closed environment crop growth data were used to develop a first photosynthetic model representing the basic carbon fixation mechanisms. This model will be further elaborated in the course of this study to predict yield, oxygen production and transpi-ration. As an ultimate goal the model is intended to simulate the composition of the different plant organs (root, shoot, fruit/seed or tuber) for each crop under various conditions. For the validation of this model an extensive amount of data sets are needed. Current plant growth bench test setups will provide part of the required data. To gain more precise and detailed datasets, a highly closed plant growth chamber (Plant Characterization Unit, PCU) is under development. The PCU will provide accurate mass balances for carbon, water, oxygen and other elements with statistical reliability. This reliability is achieved through a high degree of closure and environment homogeneity. The PCU will also provide data for the above described plant characterization studies. The general work approach, the current status and future steps will be illustrated.

  10. Escherichia coli as a fatty acid and biodiesel factory: current challenges and future directions.

    Rahman, Ziaur; Rashid, Naim; Nawab, Javed; Ilyas, Muhammad; Sung, Bong Hyun; Kim, Sun Chang

    2016-06-01

    Biodiesel has received widespread attention as a sustainable, environment-friendly, and alternative source of energy. It can be derived from plant, animal, and microbial organisms in the form of vegetable oil, fats, and lipids, respectively. However, biodiesel production from such sources is not economically feasible due to extensive downstream processes, such as trans-esterification and purification. To obtain cost-effective biodiesel, these bottlenecks need to be overcome. Escherichia coli, a model microorganism, has the potential to produce biodiesel directly from ligno-cellulosic sugars, bypassing trans-esterification. In this process, E. coli is engineered to produce biodiesel using metabolic engineering technology. The entire process of biodiesel production is carried out in a single microbial cell, bypassing the expensive downstream processing steps. This review focuses mainly on production of fatty acid and biodiesel in E. coli using metabolic engineering approaches. In the first part, we describe fatty acid biosynthesis in E. coli. In the second half, we discuss bottlenecks and strategies to enhance the production yield. A complete understanding of current developments in E. coli-based biodiesel production and pathway optimization strategies would reduce production costs for biofuels and plant-derived chemicals. PMID:26961532

  11. Beyond (eco)design: current approaches to sustainable packaging design

    Wever, R.

    2014-01-01

    Packaging has always received a lot of attention within the field of design for sustainability. The classical approach has been to mainly focus on reducing the impact of the packaging. This approach stems from the ill-informed position that packaging is superfluous, or at best there only for marketi

  12. Properties of acid-induced currents in mouse dorsal root ganglia neurons.

    Ergonul, Zuhal; Yang, Lei; Palmer, Lawrence G

    2016-05-01

    Acid-sensing ion channels (ASICs) are cation channels that are activated by protons (H(+)). They are expressed in neurons throughout the nervous system and may play important roles in several neurologic disorders including inflammation, cerebral ischemia, seizures, neurodegeneration, anxiety, depression, and migraine. ASICs generally produce transient currents that desensitize in response to a decrease in extracellular pH Under certain conditions, the inactivation of ASICs can be incomplete and allow them to produce sustained currents. Here, we characterize the properties of both transient and sustained acid-induced currents in cultured mouse dorsal root ganglia (DRG) neurons. At pH levels between 7.3 and 7.1 they include "window currents" through ASICs. With stronger acid signals sustained currents are maintained in the absence of extracellular Na(+) or the presence of the ASIC blockers amiloride and Psalmotoxin-1(PcTx1). These sustained responses may have several different origins in these cells, including acid-induced stimulation of inward Cl(-) currents, block of outward K(+) currents, and augmentation of inward H(+) currents, properties that distinguish these novel sustained currents from the well-characterized transient currents. PMID:27173673

  13. Current Concepts and Management Approaches in Nonalcoholic Fatty Liver Disease

    Attar, Bashar M.; Van Thiel, David H.

    2013-01-01

    Nonalcoholic fatty liver disease (NAFLD) is the most common cause of liver dysfunction worldwide. NAFLD may progress to nonalcoholic steatohepatitis (NASH) and in turn cirrhosis. Importantly, hepatic cancer can occur in NASH in the absence of cirrhosis. The cardinal histologic feature of NAFLD is the presence of an excessive accumulation of triacylglycerols and diacylglycerols in hepatocytes. The presence of obesity and insulin resistance lead to an increased hepatic-free fatty acid (FFA) flu...

  14. Limiting Current of Oxygen Reduction on Gas-Diffusion Electrodes for Phosphoric Acid Fuel Cells

    Li, Qingfeng; Gang, Xiao; Hjuler, Hans Aage;

    1994-01-01

    on polytetrafluorine-ethyl bonded gas-diffusion electordes in phosphoric acid with and without fluorinated additives. This provides an alternative to estimate the film thickness by combining it with the acid-adsorption measurements and the porosity analysis of the catalyst layer. It was noticed that the limiting...... expression for the limiting current density. The acid-film thickness estimated this way was found to be of 0.1 mum order of magnitude for the two types of electrodes used in phosphoric acid with and without fluorinated additives at 150-degrees-C....

  15. Tandem Wittig-ene reaction approach to kainic acid

    Majik, M.S.; Parameswaran, P.S.; Tilve, S.G.

    , India stilVe@unigoa.ac.in ReceiVed January 29, 2009 The first example of a tandem Wittig-intramolecular ene reaction approach and its application toward the synthesis of kainic acid is reported. The synthetic pathway involves conversion of prenyl bromide..., M. Tetrahedron Lett. 2008, 49, 6327. (b) Sakaguchi, H.; Tokuyama, H.; Fukuyama, T. Org. Lett. 2008, 10, 1711. (c) Jung, Y. C.; Yoon, C. H.; Turos, E.; Soo Yoo, K.; Jung, K. W. J. Org. Chem. 2007, 72, 10114. (d) Thuong, M.; Sottocornola, S.; Prestat...

  16. Update on marine omega-3 fatty acids: management of dyslipidemia and current omega-3 treatment options.

    Weintraub, Howard

    2013-10-01

    Low-density lipoprotein cholesterol (LDL-C) is currently the primary target in the management of dyslipidemia, and statins are first-line pharmacologic interventions. Adjunct therapy such as niacins, fibrates, bile acid sequestrants, or cholesterol absorption inhibitors may be considered to help reduce cardiovascular risk. This review discusses the need for alternative adjunct treatment options and the potential place for omega-3 fatty acids as such. The cardiovascular benefits of fish consumption are attributed to the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), and a variety of omega-3 fatty acid products are available with varied amounts of EPA and DHA. The product types include prescription drugs, food supplements, and medical foods sourced from fish, krill, algal and plant oils or purified from these oils. Two prescription omega-3 fatty acids are currently available, omega-3 fatty acid ethyl esters (contains both EPA and DHA ethyl esters), and icosapent ethyl (IPE; contains high-purity EPA ethyl ester). A pharmaceutical containing free fatty acid forms of omega-3 is currently in development. Omega-3 fatty acid formulations containing EPA and DHA have been shown to increase LDL-C levels while IPE has been shown to lower triglyceride levels without raising LDL-C levels, alone or in combination with statin therapy. In addition, recent studies have not been able to demonstrate reduced cardiovascular risk following treatment with fibrates, niacins, cholesterol absorption inhibitors, or omega-3 fatty acid formulations containing both EPA and DHA in statin-treated patients; thus, there remains a need for further cardiovascular outcomes studies for adjunct therapy. PMID:24075771

  17. A new approach to investigate leakage current mechanisms in infrared photodiodes from illuminated current-voltage characteristics

    This paper presents a new approach to investigate leakage current mechanisms in infrared photodiodes from the illuminated current–voltage characteristics. The example of mid-wave mercury cadmium telluride photodiodes is presented to illustrate the new approach. The new method is suitable for evaluating diodes in an array environment as advance knowledge of any of the material or device parameters are not required. The thermal saturation current is estimated from the observed open circuit voltage and zero-bias current (photo-current) of the diode. The ohmic shunt resistance is estimated from the observed maximum dynamic impedance of the diode. The experimentally observed reverse bias diode current in excess of thermal current, photo-current, and ohmic shunt current is reported to be best described by an exponential function of the type, Iexcess = Ir0 + K1 exp (K2 V), where Ir0, K1, and K2 are fitting parameters and V is the applied bias voltage. Our investigations reveal a close link between the excess current and the sources of ohmic currents in the diode. Exponential growth of excess current with the applied bias voltage has been interpreted as an indication of soft breakdown of the diodes

  18. Charged-Current and Neutral-Current Neutrino-Nucleus Scattering in a Relativistic Approach

    Giusti, Carlotta; Pacati, Franco Davide

    2009-01-01

    Relativistic models developed for the exclusive and inclusive QuasiElastic (QE) electron scattering have been extended to Charged-Current (CC) and Neutral-Current (NC) neutrino-nucleus scattering. The results of different descriptions of Final-State Interactions (FSI) are compared.

  19. Current distribution in systems with anomalous diffusion: renormalization group approach

    We investigate the asymptotic properties of the large deviation function of the integrated particle current in systems, in or out of thermal equilibrium, whose dynamics exhibits anomalous diffusion. The physical systems covered by our study include mutually repelling particles with a drift, a driven lattice gas displaying a continuous nonequilibrium phase transition and particles diffusing in an anisotropic random advective field. It is exemplified how renormalization group techniques allow for a systematic determination of power laws in the corresponding current large deviation functions. We show that the latter are governed by known universal scaling exponents, specifically the anomalous dimension of the noise correlators

  20. Separation of chlorogenic acid and concentration of trace caffeic acid from natural products by pH-zone-refining counter-current chromatography

    LU, YUANYUAN; Dong, Genlai; Gu, Yanxiang; Ito, Yoichiro; Wei, Yun

    2013-01-01

    Chlorogenic acid, a major compound among phenolic acids of Flaveria bidentis (L.) Kuntze and Flos lonicerae, was successfully separated by pH-zone-refining counter-current chromatography. Caffeic acid and chlorogenic acid were selected as test samples, which represent as phenolic acids for separation by the pH-zone-refining counter-current chromatography. The separation of these test samples was performed with two-phase solvent system composed of methyl-tert.-butyl-ether-acetonitrile-water at...

  1. Teaching Electrical Energy, Voltage and Current: An Alternative Approach.

    Licht, Pieter

    1991-01-01

    A program for teaching the concepts of electric energy, voltage, and current is proposed. The ideas and concepts are introduced in a sequence that places more emphasis on some aspects that are normally treated very briefly. A phenomenological orientation, qualitative and quantitative micro- and macroscopic treatments, and the inclusion of the…

  2. Humic Acids Enhanced U(VI) Attenuation in Acidic Waste Plumes: An In-situ Remediation Approach

    Wan, J.; Dong, W.; Tokunaga, T. K.

    2010-12-01

    In the process of extracting plutonium for nuclear weapons production during the Cold War, large volumes of acidic waste solutions containing low-level radionuclides were discharged for decades into unlined seepage basins in several US Department of Energy (DOE) weapon facilities such as the Savannah River Site (SRS), Oak Ridge (OR), and 300 Area of the Hanford Site. Although the basins have been capped and some sites have gone through many years of active remediation, groundwaters currently remain acidic with pH values as low as 3.0 near the basins, and uranium concentrations remain much higher than its maximum contaminant level (MCL). A sustainable U biogeochemical remediation method has not yet been developed, especially under acidic conditions (pH 3-5). Bioreduction-based U remediation requires permanent maintenance of reducing conditions through indefinite supply of electron donor, and when applied in acidic plumes a high-cost pretreatment procedure is required. Methods based on precipitation of phosphate minerals depend on maintenance of high P concentrations. Precipitating of uranyl vanadates can lower U to below its MCL, but this approach is only effective at near-neutral pH. There is an urgent need for developing a sustainable method to control U mobility in acidic conditions. In this paper, we propose a method of using humic acids (HAs) to attenuate contaminant U mobility in acidic waste plumes. Our laboratory experiment results show that HAs are able to strongly and quickly adsorb onto aquifer sediments from the DOE’s SRS and OR. With a moderate addition of HA, U adsorption increased to near 100% at pH below 5.0. Because U partitioning onto the HA modified mineral surfaces is so strong, U concentration in groundwaters can be sustainably reduced to below its MCL. We conducted flow through experiments for U desorption by acidic groundwater leaching at pH 3.5 and 4.5 from HA-treated SRS contaminated sediments. The results show that desorption of both U

  3. Current oscillations during the anodic dissolution of copper in trifluoroacetic acid

    A phenomenon of current oscillators was characterized crosswise active-passive potential region during the electrodissolution of copper electrode in trifluoroacetic acid (TFA). The current density-potential curves show two transition points. A potential region of current oscillations was found as a part of limiting current region. The Cu|TFA electrochemical oscillator was found to displaying rich dynamical response on varying the temperature and the applied potential. The Cu|TFA system display current oscillation behaviour from the mono-periodic to the mixed-mode (relaxation type). Changes of the electrode surface structure and morphology were investigated by X-ray diffraction spectroscopy, atomic forced microscopy and optical microscopy.

  4. Current diagnostic approach of bone tumors in childhood

    The authors analyze the magnetic resonance imaging (MRI) as the imaging modality of choice for evaluation of patients with bone tumors or soft tissue tumors. The advent of such a sensitive imaging modality is fortuitous and coincides with a recent change in the therapeutic approach to primary bone tumors. MRI is extremely valuable in monitoring the tumor response to the initial chemotherapy and is accurate defining the margins of tumor, facilitating planning of limb salvage surgical procedures. (author). 5 refs., 8 figs

  5. Multiple, sclerosis: clinical feature, pathogenesis and current therapeutical approaches

    Multiple sclerosis (MS) is considered as a T-cell mediated autoimmune disease. Caused by central nervous system demyelination and axonal damage varying clinical signs do occur either with relapsing-remitting or with chronic progressive course. Based on pathogenetic considerations immunomodulative and immunosuppressive therapeutical approaches are used to limit the disease progression. Clinical symptoms, diagnostic criteria, pathogenetical considerations, and consecutive therapeutical interventions are summarized. (orig.)

  6. Implementation of the RCM approach at EDF NPPs: Current status

    To ensure safest possible operation and to get best overall economic performance of its Nuclear Power Plants, 10 years ago Electricite de France launched a Reliability Centered Maintenance (RCM) project to optimize the preventive maintenance programs. The principles underlying the RCM approach are based on common sense: failures must be prevented by preventive maintenance operations in all cases when the repercussions for the installation could be serious or critical in term of safety, availability or maintenance costs. The approach is a 3-phases process: 1. Evaluation of the functional consequences of failures 2. Evaluation of performances based on the analysis of experience feedback 3. Optimization of the preventive maintenance tasks The new preventive maintenance programs are presently almost completed and progressively implemented. Here and now, the implementation of the RCM approach allows to emphasize some benefits: 1. Same or increased level of safety 2. Same or increased level of plant availability 3. ALARA principles better taken into account 4. Cost control 5. Positive change in maintenance culture. Some new studies are in progress, such as the development of a 'Risk Based In Service Inspection' for passive components. (author)

  7. Current treatment approaches in patients with ankylosing spondylitis

    Bilal Elbey

    2015-03-01

    Full Text Available Ankylosing spondylitis (AS is a chronic, inflammatory, rheumatic disease that mainly affects sacroiliac joints and spine. AS predominantly occurs more often in males and typically begins in the second or third decade. The mainstay of therapy in AS are nonsteroidal anti-inflammatory drugs, which reduce inflammation and pain. Disease modifying antirheumatic drugs (DMARD did not have enough evidence to prove their effect in AS treatment. The use of DMARD may not sufficient to improve the treatment and symptoms. Currently, TNF-blockers such as, Golimumab Etanersept Adalimumab İnfliksimab have promising results in the treatment of AS. TNF-blockers improve the clinical signs and symptoms, and improve the patients’ physical function and quality of life. This manuscript is focused that Current pharmacological treatments in patients with ankylosing spondylitis.

  8. Lessons from the Current Financial Crisis. A Risk Management Approach

    Gheorghe VOINEA

    2009-05-01

    Full Text Available In the last twenty years, the financial risk management has gained an important role for the companies and financial institutions. Financial innovations have improved the efficiency of risk management process, but at the same time, they have imposed new challenges for market participants and their supervisors in the areas of systemic risk. An important feature of periods of financial innovation is that the rapid increase in new products and changes in the structure of those markets can outpace the development of the risk management and processing and settlement infrastructure. The current financial crisis has revealed significant weaknesses in risk management practices across the financial services industry. This paper analyses the main lessons that can be drawn from the current financial crisis in order to improve the financial risk management.

  9. Direct current stimulation : new approach to enhancing heavy oil production

    Whittle, J.K. [Electro-Petroleum Inc., Wayne, PA (United States); Hill, D.G. [Southern California Univ., Los Angeles, CA (United States)

    2006-07-01

    The limited recovery of heavy crude oil can be attributed to the high viscosity of the liquids in the oil reservoirs. A viable technology has been lacking for the economic recovery of heavy oil. This paper discussed the advantages of direct current electrical stimulation or electro-enhanced oil recovery (EEOR). The paper outlined the advantages, including data produced from field demonstrations as well as the results of recent laboratory studies. The paper provided a historical and electro-chemical background of EEOR. Field operations that were discussed included electric field maps and a comparison of direct current versus alternating current electrical power. A series of EEOR field demonstrations were presented for the Santa Maria basin in California and the eastern Alberta plains. The paper also discussed produced fluid chemical changes and electro-osmosis and effective permeability. Last, the paper provided a comparison of EEOR to other existing and emerging technologies including steam flood; surfactant flood; co-solvent flood; carbon dioxide flood; and fire flood. It was concluded that the biggest EEOR limitation is its limited field application portfolio. EEOR has produced encouraging field demonstrations to date and has facilitated beneficial chemical changes in the produced fluids. 26 refs., 5 tabs., 10 figs.

  10. Public involvement in radioactive waste management: current approaches and experiences

    Institutions involved in radioactive waste management are facing a rapidly evolving environment stemming from societal changes, including new information technologies and new roles for the media. At the same time, some national programmes are moving from research and development to site selection and implementation, while other countries are reviewing and defining their policies in the waste management area. As in many other fields in which environmental and risk considerations are involved, demand for public participation in radioactive waste management decision making calls for new approaches towards involving stakeholders. (authors)

  11. Current approach for urinary system stone disease in pregnant women

    Orcun Celik

    2016-01-01

    Full Text Available Urinary system stones can be classified according to size, location, X-ray characteristics, aetiology of formation, composition, and risk of recurrence. Especially urolithiasis during pregnancy is a diagnostic and therapeutic challenge. In most cases, it becomes symptomatic in the second or third trimester. Diagnostic options in pregnant women are limited due to the possible teratogenic, carcinogenic, and mutagenic risk of foetal radiation exposure. Clinical management of a pregnant urolithiasis patient is complex and demands close collaboration between patient, obstetrician and urologist. We would like to review current diagnosis and treatment modalities of stone disease of pregnant woman.

  12. Current and future therapeutic approaches to the common cold.

    Mossad, Sherif B

    2003-12-01

    For decades, investigators have strived to elucidate the pathogenesis, and hence a treatment, for the common cold. Therapy has been tried with a variety of agents, ranging from anecdotal folk remedies, to well-designed medications. Measures primarily directed to relieve the symptoms of the common cold, rather than specific antimicrobial agents, are the current main stay of therapy. Millions of patients would benefit from an easy-to-perform diagnostic test and specific therapy that works quickly, shortening the duration of illness and preventing further spread of infection. PMID:15482159

  13. Current concepts in sport concussion management:A multifaceted approach

    Ashley; Littleton; Kevin; Guskiewicz

    2013-01-01

    Sport-related concussion is a common neurological injury that occurs in all levels of athletic participation.Concussions may actually go undiagnosed,as they do not always display outward signs and athletes may fail to report symptoms of concussion,either because they do not know the symptoms,or for fear of removal from play.Inappropriate management of concussion can lead to increased risk of subsequent injury.This article outlines various aspects of sport-related concussion management,including preparation/planning,education,evaluation,management,return to play decisions,and long term effects of concussion.Preparation and education are the first steps that must be taken to minimize the potentially negative consequences of concussion.If a concussion is suspected,it must be stressed that the evaluation should include a multifaceted approach,with a physical examination and assessment of signs and symptoms,neurocognition and balance.The management of concussion should include both physical and cognitive rest and factors such as transportation,sleep,work,and academics should be taken into consideration.Return to play following concussion should follow a graduated return to play protocol,with careful monitoring of symptoms.Sports medicine clinicians should stay up to date with information regarding concussion management and take a conservative approach,because there are recent reports of various cumulative effects of multiple concussions.

  14. Transient Current Behaviour of Poly (p-hydroxybenzoic acid-co-ethylene terephthalate) Liquid Crystal Polymers

    Yarramaneni, Sridharbabu; Sharma, Anu; Quamara, J. K.

    2011-07-01

    Transient current behaviour of pristine Poly (p-hydroxybenzoic acid-co-ethylene terephthalate) Liquid crystal polymer which is a copolymer of poly ethylene terephthalate and poly p-hydroxybenzoic acid referred as PET/x.PHB polymer liquid crystals have been studied at different biasing electric fields ranging from 13 kV/cm to 104.3 kV/cm and at temperatures 120° C and 250° C for molar ratio x =0.8.

  15. Current Concepts and Management Approaches in Nonalcoholic Fatty Liver Disease

    Bashar M. Attar

    2013-01-01

    Full Text Available Nonalcoholic fatty liver disease (NAFLD is the most common cause of liver dysfunction worldwide. NAFLD may progress to nonalcoholic steatohepatitis (NASH and in turn cirrhosis. Importantly, hepatic cancer can occur in NASH in the absence of cirrhosis. The cardinal histologic feature of NAFLD is the presence of an excessive accumulation of triacylglycerols and diacylglycerols in hepatocytes. The presence of obesity and insulin resistance lead to an increased hepatic-free fatty acid (FFA flux creating an environment appropriate for the development of NAFLD. The generation of toxic reactive oxygen species with the production of hepatic injury and inflammation as a consequence of FFA oxidation will ultimately lead to the initiation and progression of fibrosis. Lifestyle modifications specifically weight loss, physical exercise, and cognitive behavior therapy have been recommended as treatments for NASH. Dietary fructose is an independent risk factor for the development of NAFLD. Pioglitazone can be used to treat biopsy-proven NASH; however, its safety risks should be considered carefully. Greater consumption for coffee, independent of its caffeine component, has been associated with a significant reduced risk of advanced fibrosis in NASH. Additional data are needed before recommending bariatric surgery as an established option for the specific treatment of NASH.

  16. Current concepts and management approaches in nonalcoholic fatty liver disease.

    Attar, Bashar M; Van Thiel, David H

    2013-01-01

    Nonalcoholic fatty liver disease (NAFLD) is the most common cause of liver dysfunction worldwide. NAFLD may progress to nonalcoholic steatohepatitis (NASH) and in turn cirrhosis. Importantly, hepatic cancer can occur in NASH in the absence of cirrhosis. The cardinal histologic feature of NAFLD is the presence of an excessive accumulation of triacylglycerols and diacylglycerols in hepatocytes. The presence of obesity and insulin resistance lead to an increased hepatic-free fatty acid (FFA) flux creating an environment appropriate for the development of NAFLD. The generation of toxic reactive oxygen species with the production of hepatic injury and inflammation as a consequence of FFA oxidation will ultimately lead to the initiation and progression of fibrosis. Lifestyle modifications specifically weight loss, physical exercise, and cognitive behavior therapy have been recommended as treatments for NASH. Dietary fructose is an independent risk factor for the development of NAFLD. Pioglitazone can be used to treat biopsy-proven NASH; however, its safety risks should be considered carefully. Greater consumption for coffee, independent of its caffeine component, has been associated with a significant reduced risk of advanced fibrosis in NASH. Additional data are needed before recommending bariatric surgery as an established option for the specific treatment of NASH. PMID:23576902

  17. Adenoidectomy: current approaches and review of the literature.

    Türkoğlu Babakurban, Seda; Aydın, Erdinç

    2016-01-01

    Adenoid is a secondary lymphoid organ located in the nasopharynx. Due to its location, it plays an important role in the host defense of the upper respiratory tract. Immunoglobulin G3 and immunoglobulin A1 antibodies are prevalent antibodies in the adenoid tissue. Adenoidal hypertrophy is a common condition in children causing symptoms such as mouth breathing, nasal discharge, snoring, sleep apnea, and hyponasal speech. It also plays a role in the pathogenesis of rhinosinusitis, recurrent otitis media, and otitis media with effusion. Currently, adenoidectomy is one of the most commonly performed pediatric surgical procedures worldwide. Although there is still poor evidence in the literature, recurrent upper respiratory infections, otitis media with effusion, and obstructive sleep apnea syndrome are considered to be the main indications of adenoidectomy. Adenoidectomy can be carried out with several techniques and instruments. Although rare, surgery possesses some risks and may cause emotional distress both for the patient and the family. Non-surgical treatments such as intranasal steroids are also used in the treatment of adenoid hypertrophy. In this review, we discuss the current literature on the adenoid function, adenoidectomy indications, and treatment of adenoid hypertrophy. PMID:27107607

  18. Current concepts and future approaches to vestibular rehabilitation.

    Tjernström, Fredrik; Zur, Oz; Jahn, Klaus

    2016-04-01

    Over the last decades methods of vestibular rehabilitation to enhance adaptation to vestibular loss, habituation to changing sensory conditions, and sensory reweighting in the compensation process have been developed. However, the use of these techniques still depends to a large part on the educational background of the therapist. Individualized assessment of deficits and specific therapeutic programs for different disorders are sparse. Currently, vestibular rehabilitation is often used in an unspecific way in dizzy patients irrespective of the clinical findings. When predicting the future of vestibular rehabilitation, it is tempting to foretell advances in technology for assessment and treatment only, but the current intense exchange between clinicians and basic scientists also predicts advances in truly understanding the complex interactions between the peripheral senses and central adaptation mechanisms. More research is needed to develop reliable techniques to measure sensory dependence and to learn how this knowledge can be best used-by playing off the patient's sensory strength or working on the weakness. To be able using the emerging concepts, the neuro-otological community must strive to educate physicians, physiotherapists and nurses to perform the correct examinations for assessment of individual deficits and to look for factors that might impede rehabilitation. PMID:27083886

  19. Understanding fatty acid metabolism through an active learning approach.

    Fardilha, M; Schrader, M; da Cruz E Silva, O A B; da Cruz E Silva, E F

    2010-03-01

    A multi-method active learning approach (MALA) was implemented in the Medical Biochemistry teaching unit of the Biomedical Sciences degree at the University of Aveiro, using problem-based learning as the main learning approach. In this type of learning strategy, students are involved beyond the mere exercise of being taught by listening. Less emphasis is placed on transmitting information and the focus is shifted toward developing higher order thinking (analysis, synthesis, and evaluation). However, MALA should always involve clearly identified objectives and well-defined targets. Understanding fatty acid metabolism was one of the proposed goals of the Medical Biochemistry unit. To this end, students were challenged with a variety of learning strategies to develop skills associated with group conflict resolution, critical thinking, information access, and retrieval, as well as oral and written communication skills. Overall, students and learning facilitators were highly motivated by the diversity of learning activities, particularly due to the emphasis on correlating theoretical knowledge with human health and disease. As a quality control exercise, the students were asked to answer a questionnaire on their evaluation of the whole teaching/learning experience. Our initial analysis of the learning outcomes permits us to conclude that the approach undertaken yields results that surpass the traditional teaching methods. PMID:21567798

  20. The Hyaluronic Acid Fillers: Current Understanding of the Tissue Device Interface.

    Greene, Jacqueline J; Sidle, Douglas M

    2015-11-01

    The article is a detailed update regarding cosmetic injectable fillers, specifically focusing on hyaluronic acid fillers. Hyaluronic acid-injectable fillers are used extensively for soft tissue volumizing and contouring. Many different hyaluronic acid-injectable fillers are available on the market and differ in terms of hyaluronic acid concentration, particle size, cross-linking density, requisite needle size, duration, stiffness, hydration, presence of lidocaine, type of cross-linking technology, and cost. Hyaluronic acid is a natural component of many soft tissues, is identical across species minimizing immunogenicity has been linked to wound healing and skin regeneration, and is currently actively being studied for tissue engineering purposes. The biomechanical and biochemical effects of HA on the local microenvironment of the injected site are key to its success as a soft tissue filler. Knowledge of the tissue-device interface will help guide the facial practitioner and lead to optimal outcomes for patients. PMID:26505539

  1. Current Approaches in Implementing Citizen Science in the Classroom.

    Shah, Harsh R; Martinez, Luis R

    2016-03-01

    Citizen science involves a partnership between inexperienced volunteers and trained scientists engaging in research. In addition to its obvious benefit of accelerating data collection, citizen science has an unexplored role in the classroom, from K-12 schools to higher education. With recent studies showing a weakening in scientific competency of American students, incorporating citizen science initiatives in the curriculum provides a means to address deficiencies in a fragmented educational system. The integration of traditional and innovative pedagogical methods to reform our educational system is therefore imperative in order to provide practical experiences in scientific inquiry, critical thinking, and problem solving for school-age individuals. Citizen science can be used to emphasize the recognition and use of systematic approaches to solve problems affecting the community. PMID:27047583

  2. Current approaches on viral infection: proteomics and functional validations

    JieZheng

    2012-11-01

    Full Text Available Viruses could manipulate cellular machinery to ensure their continuous survival and thus become parasites of living organisms. Delineation of sophisticated host responses upon virus infection is a challenging task. It lies in identifying the repertoire of host factors actively involved in the viral infectious cycle and characterizing host responses qualitatively and quantitatively during viral pathogenesis. Mass spectrometry based proteomics could be used to efficiently study pathogen-host interactions and virus-hijacked cellular signaling pathways. Moreover, direct host and viral responses upon infection could be further investigated by activity based functional validation studies. These approaches involve drug inhibition of secretory pathway, immunofluorescence staining, dominant negative mutation of protein target, real time PCR, small interfering siRNA-mediated knockdown, and molecular cloning studies. In this way, functional validation could gain novel insights into the high-content proteomic dataset in an unbiased and comprehensive way.

  3. Effects of oleic acid on the high threshold barium current in seabass Dicentrarchus labrax ventricular myocytes

    Chatelier, Aurelien; Imbert, Nathalie; Zambonino, Jose-luis; McKenzie, David; Bois, P.

    2006-01-01

    The present study employed a patch clamp technique in isolated seabass ventricular myocytes to investigate the hypothesis that oleic acid (OA), a mono-unsaturated fatty acid, can exert direct effects upon whole-cell barium currents. Acute application of free OA caused a dose-dependent depression of the whole-cell barium current that was evoked by a voltage step to 0 mV from a holding potential of -80 mV. The derived 50% inhibitory concentration (IC50) was 12.49 +/- 0.27 mu mol l(-1). At a con...

  4. Effects of arachidonic acid on ATP-sensitive K+ current in murine colonic smooth muscle cells.

    Jun, Jae Yeoul; Yeum, Cheol Ho; Park, Yoo Whan; Jang, In Youb; Kong, In Deok; Sim, Jae Hoon; So, Insuk; Kim, Ki Whan; You, Ho Jin

    2002-09-01

    The effects of arachidonic acid (AA) and the mechanism through which it modulates ATP-sensitive K+ (K(ATP)) currents were examined in single smooth muscle cells of murine proximal colon. In the current-clamping mode, AA and glibenclamide induced depolarization of membrane potential. Using 0.1 mM ATP and 140 mM K+ solution in the pipette and 90 mM K+ in the bath solution at a -80 mV of holding potential, pinacidil activated the glibenclamide-sensitive inward current. The potential of these currents was reversed to near the equilibrium potential of K+ by 60 mM K+ in the bath solution. AA inhibited K(ATP) currents in a dose-dependent manner. This inhibition was not changed when 1 mM GDPbetaS was present in the pipette. Chelerythrine, protein kinase C inhibitor, did not block the AA effects. Superoxide dismutase and metabolic inhibitors (indomethacin and nordihydroguaiacretic acid) of AA did not affect the AA-induced inhibition. Eicosatetraynoic acid, a nonmetabolizable analogue of AA, inhibited the K(ATP) currents. These results suggest that AA-induced inhibition of K(ATP) currents is not mediated by G-protein or protein kinase C activation. The inhibitory action is likely to be a possible mechanism of AA-induced membrane depolarization. PMID:12396031

  5. Current approaches of managing microbial diseases: focus on nanosciences technique

    Mostafa Sayed Mostafa El-Ansary

    2015-08-01

    Full Text Available Nanoscience is a fast growing research area that focuses on producing and utilizing nanosized particles, which are measured in nanometers. Recently, nanoparticles are used in various fields. Therefore, studies on the effect of nanoparticles on microorganisms are worthy of analysis. However, using many antimicrobial agents has been avoided because of their methodical harmful effect. Hence, this review paper focuses on the use of some nanomaterials to manage microbial diseases. The discussed nanomaterials as antimicrobial agents include sliver nanoparticles, gold nanoparticles and copper nanoparticles. This review also explains the mechanisms of action of some nanotechnological products to inhibit microorganisms. There are many problems in the development of an evaluation for the effect of nanomaterials on environment. Nevertheless, the defect of the approaches used to analyze nanomaterials toxicity gives no ground for hampering the development of nanotechnologies for safety using. In order to overcome this problem, ecotoxicological studies should be extended to include the analysis of the biological safety of nanomaterials in environment and accumulate experimental data.

  6. Current and future approaches to the therapy of human rabies.

    Jackson, Alan C

    2013-07-01

    Human rabies has traditionally been considered a uniformly fatal disease. However, recent decades have seen several instances in which individuals have developed clinical signs of rabies, but survived, usually with permanent neurologic sequelae. Most of these patients had received prophylactic rabies vaccine before the onset of illness. The best outcomes have been seen in patients infected with bat viruses, which appear to be less virulent for humans than strains associated with other rabies vectors. In 2003, an article by rabies experts suggested that survival might be improved through a combination of vaccine, anti-rabies immunoglobulin, antiviral drugs and the anesthetic ketamine, which had shown benefit in an animal model. One year later, a girl in Milwaukee who developed rabies after bat exposure was treated with some of these measures, plus a drug-induced (therapeutic) coma, and survived her illness with mild neurologic sequelae. Although the positive outcome in this case has been attributed to the treatment regimen, it more likely reflects the patient's own brisk immune response, as anti-rabies virus antibodies were detected at the time of hospital admission, even though she had not been vaccinated. This conclusion is supported by the failure of the "Milwaukee Protocol" to prevent death in numerous subsequent cases. Use of this protocol should therefore be discontinued. Future research should focus on the use of animal models to improve understanding of the pathogenesis of rabies and for the development of new therapeutic approaches. PMID:23369672

  7. SAPHO Syndrome: Current Developments and Approaches to Clinical Treatment.

    Firinu, Davide; Garcia-Larsen, Vanessa; Manconi, Paolo Emilio; Del Giacco, Stefano R

    2016-06-01

    SAPHO syndrome (synovitis, acne, pustulosis, hyperostosis, and osteitis) is a rare autoimmune disease which, due to its clinical presentation and symptoms, is often misdiagnosed and unrecognized. Its main features are prominent inflammatory cutaneous and articular manifestations. Treatments with immunosuppressive drugs have been used for the management of SAPHO with variable results. To date, the use of anti-TNF-α agents has proved to be an effective alternative to conventional treatment for unresponsive or refractory SAPHO cases. TNF-α is a pro-inflammatory cytokine and pivotal regulator of other cytokines, including IL-1 β, IL-6, and IL-8, involved in inflammation, acute-phase response induction, and chemotaxis. IL-1 inhibition strategies with anakinra have shown efficacy as first and second lines of treatment. In this review, we will describe the main characteristics of biological drugs currently used for SAPHO syndrome. We also describe some of the promising therapeutic effects of ustekinumab, an antibody against the p40 subunit of IL-12 and IL-23, after failure of multiple drugs including anti-TNF-α and anakinra. We discuss the use and impact of the new anti-IL-1 antagonists involved in the IL-17 blockade, in particular for the most difficult-to-treat SAPHO cases. PMID:27108452

  8. Treatment of cutaneous melanoma: current approaches and future prospects

    Melanoma is the most aggressive and deadly type of skin cancer. Surgical resection with or without lymph node sampling is the standard of care for primary cutaneous melanoma. Adjuvant therapy decisions may be informed by careful consideration of prognostic factors. High-dose adjuvant interferon alpha-2b increases disease-free survival and may modestly improve overall survival. Less toxic alternatives for adjuvant therapy are currently under study. External beam radiation therapy is an option for nodal beds where the risk of local recurrence is very high. In-transit melanoma metastases may be treated locally with surgery, immunotherapy, radiation, or heated limb perfusion. For metastatic melanoma, the options include chemotherapy or immunotherapy; targeted anti-BRAF and anti-KIT therapy is under active investigation. Standard chemotherapy yields objective tumor responses in approximately 10%–20% of patients, and sustained remissions are uncommon. Immunotherapy with high-dose interleukin-2 yields objective tumor responses in a minority of patients; however, some of these responses may be durable. Identification of activating mutations of BRAF, NRAS, c-KIT, and GNAQ in distinct clinical subtypes of melanoma suggest that these are molecularly distinct. Emerging data from clinical trials suggest that substantial improvements in the standard of care for melanoma may be possible

  9. Current approaches toward production of secondary plant metabolites

    Md. Sarfaraj Hussain

    2012-01-01

    Full Text Available Plants are the tremendous source for the discovery of new products with medicinal importance in drug development. Today several distinct chemicals derived from plants are important drugs, which are currently used in one or more countries in the world. Secondary metabolites are economically important as drugs, flavor and fragrances, dye and pigments, pesticides, and food additives. Many of the drugs sold today are simple synthetic modifications or copies of the naturally obtained substances. The evolving commercial importance of secondary metabolites has in recent years resulted in a great interest in secondary metabolism, particularly in the possibility of altering the production of bioactive plant metabolites by means of tissue culture technology. Plant cell and tissue culture technologies can be established routinely under sterile conditions from explants, such as plant leaves, stems, roots, and meristems for both the ways for multiplication and extraction of secondary metabolites. In vitro production of secondary metabolite in plant cell suspension cultures has been reported from various medicinal plants, and bioreactors are the key step for their commercial production. Based on this lime light, the present review is aimed to cover phytotherapeutic application and recent advancement for the production of some important plant pharmaceuticals.

  10. Treatment of cutaneous melanoma: current approaches and future prospects

    Alain P Algazi

    2010-08-01

    Full Text Available Alain P Algazi1, Christopher W Soon2, Adil I Daud11Department of Medicine, Division of Hematology and Oncology, 2Department of Dermatology, University of California, San Francisco San Francisco, CA, USAAbstract: Melanoma is the most aggressive and deadly type of skin cancer. Surgical resection with or without lymph node sampling is the standard of care for primary cutaneous melanoma. Adjuvant therapy decisions may be informed by careful consideration of prognostic factors. High-dose adjuvant interferon alpha-2b increases disease-free survival and may modestly improve overall survival. Less toxic alternatives for adjuvant therapy are currently under study. External beam radiation therapy is an option for nodal beds where the risk of local recurrence is very high. In-transit melanoma metastases may be treated locally with surgery, immunotherapy, radiation, or heated limb perfusion. For metastatic melanoma, the options include chemotherapy or immunotherapy; targeted anti-BRAF and anti-KIT therapy is under active investigation. Standard chemotherapy yields objective tumor responses in approximately 10%–20% of patients, and sustained remissions are uncommon. Immunotherapy with high-dose interleukin-2 yields objective tumor responses in a minority of patients; however, some of these responses may be durable. Identification of activating mutations of BRAF, NRAS, c-KIT, and GNAQ in distinct clinical subtypes of melanoma suggest that these are molecularly distinct. Emerging data from clinical trials suggest that substantial improvements in the standard of care for melanoma may be possible.Keywords: melanoma, resection, immune modulation, small molecule kinase inhibitors, chemotherapy, clinical trials

  11. The effect of the fast neutron current on the amino acid contents and nucleic acid synthesis in maize plants

    At the present time the effects of external influences on the genetic structures of the plant cells and the transmission of the accepted signals to other cellular structures and then to the whole organism have actively been studied. According to the opinion of a number of authors the gene expression and repression are immediate responses to the environment changes. To affect the plant genetic apparatus it is quite enough to expose it to some factors such as gamma rays, X- rays, neutron currents, saline-, temperature- or osmotic stresses. At the current stage of the research of the molecular mechanisms of the plant adaptation to the environment changes the priority goal is to ascertain the nature of the influence of the above mentioned factors on the processes of DNA replication and transcription, as the nucleic acids are the targets for external effects. The fast neutron current is one of the factors that influence the plant growth and development. Unlike gamma rays, the mechanism of the neutron irradiation on the plant genetic apparatus is very poorly studied. The objective of our research was the study of the fast neutron current effects on the DNA replication and transcription processes and amino acid synthesis in the irradiated maize plants

  12. Microbial Production of Short Chain Fatty Acids from Lignocellulosic Biomass: Current Processes and Market

    Baumann, Ivan

    2016-01-01

    Biological production of organic acids from conversion of biomass derivatives has received increased attention among scientists and engineers and in business because of the attractive properties such as renewability, sustainability, degradability, and versatility. The aim of the present review is to summarize recent research and development of short chain fatty acids production by anaerobic fermentation of nonfood biomass and to evaluate the status and outlook for a sustainable industrial production of such biochemicals. Volatile fatty acids (VFAs) such as acetic acid, propionic acid, and butyric acid have many industrial applications and are currently of global economic interest. The focus is mainly on the utilization of pretreated lignocellulosic plant biomass as substrate (the carbohydrate route) and development of the bacteria and processes that lead to a high and economically feasible production of VFA. The current and developing market for VFA is analyzed focusing on production, prices, and forecasts along with a presentation of the biotechnology companies operating in the market for sustainable biochemicals. Finally, perspectives on taking sustainable product of biochemicals from promise to market introduction are reviewed. PMID:27556042

  13. Microbial Production of Short Chain Fatty Acids from Lignocellulosic Biomass: Current Processes and Market.

    Baumann, Ivan; Westermann, Peter

    2016-01-01

    Biological production of organic acids from conversion of biomass derivatives has received increased attention among scientists and engineers and in business because of the attractive properties such as renewability, sustainability, degradability, and versatility. The aim of the present review is to summarize recent research and development of short chain fatty acids production by anaerobic fermentation of nonfood biomass and to evaluate the status and outlook for a sustainable industrial production of such biochemicals. Volatile fatty acids (VFAs) such as acetic acid, propionic acid, and butyric acid have many industrial applications and are currently of global economic interest. The focus is mainly on the utilization of pretreated lignocellulosic plant biomass as substrate (the carbohydrate route) and development of the bacteria and processes that lead to a high and economically feasible production of VFA. The current and developing market for VFA is analyzed focusing on production, prices, and forecasts along with a presentation of the biotechnology companies operating in the market for sustainable biochemicals. Finally, perspectives on taking sustainable product of biochemicals from promise to market introduction are reviewed. PMID:27556042

  14. Determination of complex formation constants by phase sensitive alternating current polarography: Cadmium-polymethacrylic acid and cadmium-polygalacturonic acid.

    Garrigosa, Anna Maria; Gusmão, Rui; Ariño, Cristina; Díaz-Cruz, José Manuel; Esteban, Miquel

    2007-10-15

    The use of phase sensitive alternating current polarography (ACP) for the evaluation of complex formation constants of systems where electrodic adsorption is present has been proposed. The applicability of the technique implies the previous selection of the phase angle where contribution of capacitive current is minimized. This is made using Multivariate Curve Resolution by Alternating Least Squares (MCR-ALS) in the analysis of ACP measurements at different phase angles. The method is checked by the study of the complexation of Cd by polymethacrylic (PMA) and polygalacturonic (PGA) acids, and the optimal phase angles have been ca. -10 degrees for Cd-PMA and ca. -15 degrees for Cd-PGA systems. The goodness of phase sensitive ACP has been demonstrated comparing the determined complex formation constants with those obtained by reverse pulse polarography, a technique that minimizes the electrode adsorption effects on the measured currents. PMID:19073101

  15. Current ideas on the pathogenesis of uric acid nephrolithiasis and its correction methods in gouty patients

    V G Barskova

    2011-12-01

    Full Text Available output The paper describes current ideas on the pathogenesis and treatment of nephrolithiasis, virtually a constant attendant of gout. The prevalence of nephrolithiasis is reported to be increasing worldwide. Among all cases of nephrolithiasis, the frequency of uric acid nephrolithiasis ranges from 5 to 40%; that of nephrolithiasis in gout is, according to the data by different authors, 7 to 10%. Hyperuricosuria, low urine volume, and low urine pH are considered to be classical risk factors for uric acid nephrolithiasis. Uric acid nephrolithiasis, including that in gout, even if asymptomatic, is noted to require active therapy. The paper presents the basic principles of treatment for uric acid nephrolithiasis: to normalize urine pH; to eliminate or neutralize the sequels of hyperuricosuria, to correct comorbidities, and to increase urine.

  16. Current knowledge on mycolic acids in Corynebacterium glutamicum and their relevance for biotechnological processes.

    Lanéelle, Marie-Antoinette; Tropis, Maryelle; Daffé, Mamadou

    2013-12-01

    Corynebacterium glutamicum is the world's largest producer of glutamate and lysine. Industrial glutamate overproduction is induced by empirical processes, such as biotin limitation, supplementation with specific surfactants or addition of sublethal concentration of certain antibiotics to the culture media. Although Gram-positive bacteria, C. glutamicum and related bacterial species and genera contain, in addition to the plasma membrane, an outer permeability membrane similar to that of Gram-negative microorganisms. As the amino acids have to cross both membranes, their integrity, composition and fluidity influence the export process. While the precise mechanism of the export of the amino acids by C. glutamicum is not fully understood, the excretion of amino acids through the inner membrane involved at least a major export system mechanosensitive channel MscS family (MscCG) encoded by NCgl1221. As the various industrial treatments have been shown to affect the lipid content of the bacterial cell, it is strongly believed that defects in the hallmark of the outer membrane, 2-alkyl, 3-hydroxylated long-chain fatty acids (mycolic acids), could be key factors in the glutamate overproduction. This review aims at giving an overview of the current knowledge on mycolic acids structure, biosynthesis and transfer in C. glutamicum and their relevance for amino acid biotechnological production. PMID:24113823

  17. Nucleic Acid Aptamers Against Biotoxins: A New Paradigm Toward the Treatment and Diagnostic Approach

    Lauridsen, Lasse Holm; Veedu, Rakesh N.

    2012-01-01

    Nucleic acid aptamers are short single-stranded DNA or RNA oligonucleotides that can bind to their targets with very high affinity and specificity, and are generally selected by a process referred to as systematic evolution of ligands by exponential enrichment. Conventional antibody-based therape...... nucleic acid aptamers developed against various biotoxins of plant, microorganism, or animal origin and show how these can be used in diagnostics (e.g., biosensors) and therapy.......-based therapeutic and diagnostic approach currently employed against biotoxins pose major limitations such as the requirement of a live animal for the in vivo enrichment of the antibody species, decreased stability, high production cost, and side effects. Aptamer technology is a viable alternative that can be used...

  18. Accumulation and Clearance of Perfluorooctanoic Acid (PFOA) in Current and Former Residents of an Exposed Community

    Seals, Ryan; Bartell, Scott M; Steenland, Kyle

    2010-01-01

    Background Perfluorooctanoic acid (PFOA) is a perfluoroalkyl acid found in > 99% of Americans. Its health effects are unknown. Prior estimates of serum half-life range from 2.3 to 3.8 years. Objectives We assessed the impact of years of residence and years since residing in the study area on serum PFOA concentration in a sample of current and former residents who were exposed to PFOA emissions from an industrial facility in six water districts in West Virginia and Ohio. Methods Serum samples ...

  19. Accumulation and Clearance of Perfluorooctanoic Acid (PFOA) in Current and Former Residents of an Exposed Community

    Seals, Ryan; Bartell, Scott M; Steenland, Kyle

    2010-01-01

    Background: Perfluorooctanoic acid (PFOA) is a perfluoroalkyl acid found in > 99% of Americans. Its health effects are unknown. Prior estimates of serum half-life range from 2.3 to 3.8 years. Objectives: We assessed the impact of years of residence and years since residing in the study area on serum PFOA concentration in a sample of current and former residents who were exposed to PFOA emissions from an industrial facility in six water districts in West Virginia and Ohio. Methods: Serum sampl...

  20. Technological approaches to minimize industrial trans fatty acids in foods.

    Menaa, Farid; Menaa, Abder; Tréton, Jacques; Menaa, Bouzid

    2013-03-01

    Trans fatty acids (TFAs) mainly arise from 2 major sources: natural ruminal hydrogenation and industrial partial catalytic hydrogenation. Increasing evidence suggests that most TFAs and their isomers cause harmful health effects (that is, increased risk of cardiovascular diseases). Nevertheless, in spite of the existence of an international policy consensus regarding the need for public health action, several countries (for example, France) do not adopt sufficient voluntary approaches (for example, governmental regulations and systematic consumer rejections) nor sufficient industrial strategies (for example, development of healthier manufacturing practices and innovative processes such as fat interesterifications) to eliminate deleterious TFAs from processed foods while ensuring the overall quality of the final product (for example, nutritional value and stability). In this manuscript, we first review the physical-chemical properties of TFAs, their occurrence in processed foods, their main effects on health, and the routine analytical methods to characterize TFAs, before emphasizing on the major industrial methods (that is, fat food reformulation, fat interesterification, genetically modified FAs composition) that can be used worldwide to reduce TFAs in foods. PMID:23458752

  1. A Sustainable Approach for Acid Rock Drainage Treatment using Clinoptilolite

    Li, L. Y.; Xu, W.; Grace, J. R.

    2009-04-01

    Problems related to acid rock drainage (ARD) occur along many highways of British Columbia. The ARD problem at Pennask Creek along Highway 97C in the Thompson-Okanagan region is an ideal site for pilot study to investigate a possible remediation solution. The highway was opened in 1991. An ARD problem was identified in 1997. Both sides of Highway 97C are producing acidified runoff from both cut rock surface and a fractured ditch. This runoff eventually enters Pennask Creek, the largest spawning source of rainbow trout in British Columbia. The current remediation technique using limestone for ARD treatment appears to be unnecessarily expensive, to generate additional solid waste and to not be optimally effective. A soil mineral natural zeolite - clinoptilolite - which is inexpensive and locally available, has a high metal adsorption capacity and a significant buffering capacity. Moreover, the clinoptilolite materials could be back-flushed and reused on site. An earlier batch adsorption study from our laboratory demonstrated that clinoptilolite has a high adsorption capacity for Cu, Zn, Al, with adsorption concentrations 131, 158 and 215 mg/kg clinoptilolite, respectively, from ARD of pH 3.3. Removal of metals from the loaded clinoptilolite by back-flushing was found to depend on the pH, with an optimum pH range for extraction of 2.5 to 4.0 for a contact time of one hour. The rank of desorption effectiveness was EDTA > NaCl > NaNO3 > NaOAC > NaHCO3 > Na2CO3 > NaOH > Ca(OH)2. A novel process involving cyclic adsorption on clinoptilolite followed by regeneration of the sorbent by desorption is examined for the removal of heavy metals from acid rock drainage. Experimental results show that the adsorption of zinc and copper depends on the pH and on external mass transfer. Desorption is assisted by adding NaCl to the water. A slurry bubble column was able to significantly reduce the time required for both adsorption and desorption in batch tests. XRD analysis indicated

  2. Metabolic engineering of Saccharomyces cerevisiae for production of carboxylic acids: current status and challenges

    Abbott, D.A.; Zelle, R.M.; Pronk, J T; van Maris, A. J. A.

    2009-01-01

    To meet the demands of future generations for chemicals and energy and to reduce the environmental footprint of the chemical industry, alternatives for petrochemistry are required. Microbial conversion of renewable feedstocks has a huge potential for cleaner, sustainable industrial production of fuels and chemicals. Microbial production of organic acids is a promising approach for production of chemical building blocks that can replace their petrochemically derived equivalents. Although Sacch...

  3. Polyethersulfone improves isothermal nucleic acid amplification compared to current paper-based diagnostics.

    Linnes, J C; Rodriguez, N M; Liu, L; Klapperich, C M

    2016-04-01

    Devices based on rapid, paper-based, isothermal nucleic acid amplification techniques have recently emerged with the potential to fill a growing need for highly sensitive point-of-care diagnostics throughout the world. As this field develops, such devices will require optimized materials that promote amplification and sample preparation. Herein, we systematically investigated isothermal nucleic acid amplification in materials currently used in rapid diagnostics (cellulose paper, glass fiber, and nitrocellulose) and two additional porous membranes with upstream sample preparation capabilities (polyethersulfone and polycarbonate). We compared amplification efficiency from four separate DNA and RNA targets (Bordetella pertussis, Chlamydia trachomatis, Neisseria gonorrhoeae, and Influenza A H1N1) within these materials using two different isothermal amplification schemes, helicase dependent amplification (tHDA) and loop-mediated isothermal amplification (LAMP), and traditional PCR. We found that the current paper-based diagnostic membranes inhibited nucleic acid amplification when compared to membrane-free controls; however, polyethersulfone allowed for efficient amplification in both LAMP and tHDA reactions. Further, observing the performance of traditional PCR amplification within these membranes was not predicative of their effects on in situ LAMP and tHDA. Polyethersulfone is a new material for paper-based nucleic acid amplification, yet provides an optimal support for rapid molecular diagnostics for point-of-care applications. PMID:26906904

  4. Multiple effects of nordihydroguaiaretic acid on ionic currents in rat isolated type I carotid body cells

    Hatton, C J; Peers, C

    1997-01-01

    The effects of the lipoxygenase inhibitor nordihydroguaiaretic acid (NDGA) on the ionic currents of rat carotid body type I cells were investigated by use of whole-cell and outside-out patch clamp techniques.NDGA (5–50 μM) produced a concentration-dependent inhibition of whole-cell K+ currents at all activating test potentials (holding potential −70 mV). The time-course of the inhibition was also concentration-dependent and the effects of NDGA were only reversible following brief periods of e...

  5. A new approach for noninvasive transdermal determination of blood uric acid levels

    Ching CTS

    2014-06-01

    Full Text Available Congo Tak-Shing Ching,1,2 Kok-Khun Yong,3 Yan-Dong Yao,4 Huan-Ting Shen,3 Shiu-Man Hsieh,5 Deng-Yun Jheng,1 Tai-Ping Sun,1,6 Hsiu-Li Shieh11Department of Electrical Engineering, National Chi Nan University, Nantou, 2Department of Photonics and Communication Engineering, Asia University, Taichung, 3Department of Internal Medicine, Puli Christian Hospital, Nantou, People’s Republic of China; 4Division of Science and Technology, Hong Kong Community College, Hong Kong; 5Department of Orthopedic Surgery, Puli Christian Hospital, 6Department of Electronic Engineering, Nan Kai University of Technology, Nantou, People’s Republic of ChinaAbstract: The aims of this study were to investigate the most effective combination of physical forces from laser, electroporation, and reverse iontophoresis for noninvasive transdermal extraction of uric acid, and to develop a highly sensitive uric acid biosensor (UAB for quantifying the uric acid extracted. It is believed that the combination of these physical forces has additional benefits for extraction of molecules other than uric acid from human skin. A diffusion cell with porcine skin was used to investigate the most effective combination of these physical forces. UABs coated with ZnO2 nanoparticles and constructed in an array configuration were developed in this study. The results showed that a combination of laser (0.7 W, electroporation (100 V/cm2, and reverse iontophoresis (0.5 mA/cm2 was the most effective and significantly enhanced transdermal extraction of uric acid. A custom-designed UAB coated with ZnO2 nanoparticles and constructed in a 1×3 array configuration (UAB-1×3-ZnO2 demonstrated enough sensitivity (9.4 µA/mM for quantifying uric acid extracted by the combined physical forces of laser, electroporation, and RI. A good linear relationship (R2=0.894 was demonstrated to exist between the concentration of uric acid (0.2–0.8 mM inside the diffusion cell and the current response of the

  6. Reconstructing Amino Acid Interaction Networks by an Ant Colony Approach

    Gaci, Omar; Balev, Stefan

    2009-01-01

    In this paper we introduce the notion of protein interaction network. This is a graph whose vertices are the proteins amino acids and whose edges are the interactions between them. We consider the problem of reconstructing protein's interaction network from its amino acid sequence. We rely on a probability that two amino acids interact as a function of their physico-chemical properties coupled to an ant colony system to solve this problem.

  7. Metabolic engineering of Saccharomyces cerevisiae for production of carboxylic acids: current status and challenges.

    Abbott, Derek A; Zelle, Rintze M; Pronk, Jack T; van Maris, Antonius J A

    2009-12-01

    To meet the demands of future generations for chemicals and energy and to reduce the environmental footprint of the chemical industry, alternatives for petrochemistry are required. Microbial conversion of renewable feedstocks has a huge potential for cleaner, sustainable industrial production of fuels and chemicals. Microbial production of organic acids is a promising approach for production of chemical building blocks that can replace their petrochemically derived equivalents. Although Saccharomyces cerevisiae does not naturally produce organic acids in large quantities, its robustness, pH tolerance, simple nutrient requirements and long history as an industrial workhorse make it an excellent candidate biocatalyst for such processes. Genetic engineering, along with evolution and selection, has been successfully used to divert carbon from ethanol, the natural endproduct of S. cerevisiae, to pyruvate. Further engineering, which included expression of heterologous enzymes and transporters, yielded strains capable of producing lactate and malate from pyruvate. Besides these metabolic engineering strategies, this review discusses the impact of transport and energetics as well as the tolerance towards these organic acids. In addition to recent progress in engineering S. cerevisiae for organic acid production, the key limitations and challenges are discussed in the context of sustainable industrial production of organic acids from renewable feedstocks. PMID:19566685

  8. Current Evidence Supporting the Link Between Dietary Fatty Acids and Cardiovascular Disease.

    Hammad, Shatha; Pu, Shuaihua; Jones, Peter J

    2016-05-01

    Lack of consensus exists pertaining to the scientific evidence regarding effects of various dietary fatty acids on cardiovascular disease (CVD) risk. The objective of this article is to review current evidence concerning cardiovascular health effects of the main dietary fatty acid types; namely, trans (TFA), saturated (SFA), polyunsaturated (PUFA; n-3 PUFA and n-6 PUFA), and monounsaturated fatty acids (MUFA). Accumulating evidence shows negative health impacts of TFA and SFA; both may increase CVD risk. Policies have been proposed to reduce TFA and SFA consumption to less than 1 and 7 % of energy intake, respectively. Cardiovascular health might be promoted by replacing SFA and TFA with n-6 PUFA, n-3 PUFA, or MUFA; however, the optimal amount of PUFA or MUFA that can be used to replace SFA and TFA has not been defined yet. Evidence suggests of the potential importance of restricting n-6 PUFA up to 10 % of energy and obtaining an n-6/n-3 ratio as close as possible to unity, along with a particular emphasis on consuming adequate amounts of essential fatty acids. The latest evidence shows cardioprotective effects of MUFA-rich diets, especially when MUFA are supplemented with essential fatty acids; namely, docosahexaenoic acid. MUFA has been newly suggested to be involved in regulating fat oxidation, energy metabolism, appetite sensations, weight maintenance, and cholesterol metabolism. These favorable effects might implicate MUFA as the preferable choice to substitute for other fatty acids, especially given the declaration of its safety for up to 20 % of total energy. PMID:26719191

  9. Wheat flour based propionic acid fermentation: an economic approach.

    Kagliwal, Lalit D; Survase, Shrikant A; Singhal, Rekha S; Granström, Tom

    2013-02-01

    A process for the fermentative production of propionic acid from whole wheat flour using starch and gluten as nutrients is presented. Hydrolysis of wheat flour starch using amylases was optimized. A batch fermentation of hydrolysate supplemented with various nitrogen sources using Propionibacterium acidipropionici NRRL B 3569 was performed. The maximum production of 48.61, 9.40, and 11.06 g of propionic acid, acetic acid and succinic acid, respectively, was found with wheat flour hydrolysate equivalent to 90 g/l glucose and supplemented with 15 g/l yeast extract. Further, replacement of yeast extract with wheat gluten hydrolysate showed utilization of gluten hydrolysate without compromising the yields and also improving the economics of the process. The process so developed could be useful for production of animal feed from whole wheat with in situ production of preservatives, and also suggest utilization of sprouted or germinated wheat for the production of organic acids. PMID:23357590

  10. New yeast-based approaches in production of palmitoleic acid.

    Kolouchová, Irena; Sigler, Karel; Schreiberová, Olga; Masák, Jan; Řezanka, Tomáš

    2015-09-01

    Palmitoleic acid is found in certain dairy products and has broad applications in medicine and cosmetics. We tried to find a suitable producer of this acid among traditional biotechnological yeast species (Kluyveromyces polysporus, Torulaspora delbrueckii, Saccharomyces cerevisiae) characterized by high biomass yield and Candida krusei, Yarrowia lipolytica and Trichosporon cutaneum accumulating large amounts of lipids. The main factor affecting the content of palmitoleic acid was found to be the C/N ratio in the culture medium, with ammonium sulfate as an optimum nitrogen source leading to highest biomass yield with concomitantly increased lipid accumulation, and an increased content of ω6-linoleic acid, the precursor of prostaglandins, leukotrienes, and thromboxanes. We found that C. krusei can be conveniently used for the purpose, albeit only under certain cultivation conditions, whereas S. cerevisiae can produce high and stable amounts of palmitoleic acid in a broad range of cultivation conditions ranging from conventional to nutrient limitations. PMID:26101962

  11. A system identification based approach for pulsed eddy current non-destructive evaluation

    Lang, Z.Q.; Agurto, A.; Tian, G. Y.; Sophian, A.

    2007-01-01

    This paper is concerned with the development of a new system identification based approach for pulsed eddy current non-destructive evaluation and the use of the new approach in experimental studies to verify its effectiveness and demonstrate its potential in engineering applications.

  12. Current evidence linking polyunsaturated fatty acids (PUFAs with cancer risk and progression

    MariaAzrad

    2013-09-01

    Full Text Available There is increasing evidence that polyunsaturated fatty acids (PUFAs play a role in cancer risk and progression. The n-3 family of PUFAs includes alpha-linolenic acid (ALA, eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA while the n-6 family includes linolenic acid (LA and arachidonic acid (AA. EPA and DHA are precursors for anti-inflammatory lipid mediators while AA is a precursor for pro-inflammatory lipid mediators. Collectively, PUFAs play crucial roles in maintaining cellular homeostasis, and perturbations in dietary intake or PUFA metabolism could result in cellular dysfunction and contribute to cancer risk and progression. Epidemiologic studies provide an inconsistent picture of the associations between dietary PUFAs and cancer. This discrepancy may reflect the difficulties in collecting accurate dietary data; however, it also may reflect genetic variation in PUFA metabolism which has been shown to modify physiological levels of PUFAs and cancer risk. Also, host-specific mutations as a result of cellular transformation could modify metabolism of PUFAs in the target-tissue. Clinical trials have shown that supplementation with PUFAs or foods high in PUFAs can affect markers of inflammation, immune function, tumor biology and prognosis. Preclinical investigations have begun to elucidate how PUFAs may mediate cell proliferation, apoptosis and angiogenesis and the signaling pathways involved in these processes. The purpose of this review is to summarize the current evidence linking PUFAs and their metabolites with cancer and the molecular mechanisms that underlie this association. Identifying the molecular mechanism(s through which PUFAs affect cancer risk and progression will provide an opportunity to pursue focused dietary interventions that could translate into the development of personalized diets for cancer control.

  13. A Green Approach to the Production of Hybrid Diindolylmethane-Phenylboronic Acids via a 3MCR: Promising Antineoplasic Molecules

    Mónica Zarco Juarez; Joel Omar Martínez; Olivia Noguez Cordova; María Inés Nicolás Vazquez; Teresa Ramírez-Apan; Javier Pérez Flores; René Miranda Ruvalcaba; Gabriel Arturo Arroyo Razo

    2013-01-01

    The current role of the “Green Chemistry Protocol” in multicomponent reactions is first highlighted. Then, the green approach to the production of three novel hybrid diindolylmethanes-phenylboronic acids via a 3MCR is discussed, which features the following: solventless conditions, the use of microwave irradiation to activate the reactions, the absence of catalyst, and an efficient atom economy. The products were achieved with moderate yields (41–61%) within a short time frame (5 min) and app...

  14. A self-sensing active magnetic bearing based on a direct current measurement approach.

    Niemann, Andries C; van Schoor, George; du Rand, Carel P

    2013-01-01

    Active magnetic bearings (AMBs) have become a key technology in various industrial applications. Self-sensing AMBs provide an integrated sensorless solution for position estimation, consolidating the sensing and actuating functions into a single electromagnetic transducer. The approach aims to reduce possible hardware failure points, production costs, and system complexity. Despite these advantages, self-sensing methods must address various technical challenges to maximize the performance thereof. This paper presents the direct current measurement (DCM) approach for self-sensing AMBs, denoting the direct measurement of the current ripple component. In AMB systems, switching power amplifiers (PAs) modulate the rotor position information onto the current waveform. Demodulation self-sensing techniques then use bandpass and lowpass filters to estimate the rotor position from the voltage and current signals. However, the additional phase-shift introduced by these filters results in lower stability margins. The DCM approach utilizes a novel PA switching method that directly measures the current ripple to obtain duty-cycle invariant position estimates. Demodulation filters are largely excluded to minimize additional phase-shift in the position estimates. Basic functionality and performance of the proposed self-sensing approach are demonstrated via a transient simulation model as well as a high current (10 A) experimental system. A digital implementation of amplitude modulation self-sensing serves as a comparative estimator. PMID:24030681

  15. A Self-Sensing Active Magnetic Bearing Based on a Direct Current Measurement Approach

    Carel P. du Rand

    2013-09-01

    Full Text Available Active magnetic bearings (AMBs have become a key technology in various industrial applications. Self-sensing AMBs provide an integrated sensorless solution for position estimation, consolidating the sensing and actuating functions into a single electromagnetic transducer. The approach aims to reduce possible hardware failure points, production costs, and system complexity. Despite these advantages, self-sensing methods must address various technical challenges to maximize the performance thereof. This paper presents the direct current measurement (DCM approach for self-sensing AMBs, denoting the direct measurement of the current ripple component. In AMB systems, switching power amplifiers (PAs modulate the rotor position information onto the current waveform. Demodulation self-sensing techniques then use bandpass and lowpass filters to estimate the rotor position from the voltage and current signals. However, the additional phase-shift introduced by these filters results in lower stability margins. The DCM approach utilizes a novel PA switching method that directly measures the current ripple to obtain duty-cycle invariant position estimates. Demodulation filters are largely excluded to minimize additional phase-shift in the position estimates. Basic functionality and performance of the proposed self-sensing approach are demonstrated via a transient simulation model as well as a high current (10 A experimental system. A digital implementation of amplitude modulation self-sensing serves as a comparative estimator.

  16. Nucleic Acids in Human Glioma Treatment: Innovative Approaches and Recent Results

    S. Catuogno

    2012-01-01

    Full Text Available Gliomas are the most common primary central nervous system tumors with a dismal prognosis. Despite recent advances in surgery, radiotherapy, and chemotherapy, current treatment regimens have a modest survival benefit. A crucial challenge is to deliver drugs effectively to invasive glioma cells residing in a sanctuary within the central nervous system. New therapies are essential, and oligonucleotide-based approaches, including antisense, microRNAs, small interfering RNAs, and nucleic acid aptamers, may provide a viable strategy. Thanks to their unique characteristics (low size, good affinity for the target, no immunogenicity, chemical structures that can be easily modified to improve their in vivo applications, these molecules may represent a valid alternative to antibodies particularly to overcome challenges presented by the blood-brain barrier. Here we will discuss recent results on the use of oligonucleotides that will hopefully provide new effective treatment for gliomas.

  17. New approaches to the analysis of clavulanic acid

    Clavulanic acid is an effective beta-lactamase inhibitor. Therefore, it has the potential to be used against antibiotic resistance in cases where bacteria have gained the ability to produce beta-lactamases. Clavulanic acid is synthesized biotechnologically by streptomyces clavuligerus-strains, which have to be optimized to a high clavulanic acid output. Efficient analytical techniques for clavulanic acid, its biosynthesis precursors and side products are essential for respective research. For determination of clavulanic acid in fermentation broth a rapid and efficient capillary electrophoresis method with UV-detection at 200 nm was established. Analysis could be done within less than 5 minutes. The separation itself only requires one minute. The accuracy of the method was estimated by comparison with an existing HPLC-method. In order to improve selective and sensitive detection in chromatography for the precursors and side products of clavulanic acid, derivatizations were investigated systematically. For compounds with a bicyclus structure like clavulanic acid this was done by the reaction with imidazole. The derivatization products were analyzed by capillary electrophoresis, reversed phase chromatography, ion exchange chromatography and ion pair chromatography. Detection took place by UV-absorption at 312 nm. The chromatographic techniques were hyphenated with electrospray mass spectrometry for identification of the derivatives. By employing perfluorinated detergents this was possible for ion pair chromatography too. For those biosynthesis precursors which contain a guanidino group, a pre-column derivatization method with ninhydrin was generated. The appropriate reaction products were analyzed by reversed phase chromatography und fluorescence detection. The proposed structures could be proved by coupling with electrospray mass spectrometry. Another part of this dissertation deals with the identification of decomposition products of clavulanic acid. The

  18. Transuranic removal from neutralized current acid waste with pneumatic hydropulse filtration

    Neutralized current acid waste (NCAW) is generated by the solvent extraction portion of the PUREX process. It contains <20% solids by volume, and is currently stored in underground tanks at Hanford. These solids contain the transuranic (TRU) elements and most of the fission products and will be converted to glass for permanent disposal. Because of the high cost of vitrification and repository disposal, there is a large economic incentive to minimize volume. Separation of the solids from the supernatant liquor provides a more concentrated high-level waste stream for vitrification, thereby reducing the cost. Removal of the solids will also provide an approximately TRU- free supernatant liquor which can be disposed of as grout in near-surface facilities. Allowing the solids to settle, then decanting (settle/decant) and filtering the supernatant are the principal unit operations used for TRU removal. These unit operations as shown will be used at the B Plant, an existing facility at the Hanford Site

  19. New yeast-based approaches in production of palmitoleic acid

    Kolouchová, I.; Sigler, Karel; Schreiberová, O.; Masák, J.; Řezanka, Tomáš

    2015-01-01

    Roč. 192, SEP 2015 (2015), s. 726-734. ISSN 0960-8524 R&D Projects: GA ČR(CZ) GAP503/11/0215; GA ČR GA14-00227S Institutional support: RVO:61388971 Keywords : Oleaginous yeasts * Non-oleaginous yeasts * Palmitoleic acid Subject RIV: EE - Microbiology, Virology Impact factor: 4.494, year: 2014

  20. A Gaming Approach to the Acid Rain Problem.

    Baba, Norio; And Others

    1984-01-01

    Describes an educational microcomputer gaming system for dealing with the acid rain problem in Western Europe and discusses its objectives, rules, problems, and future perspectives. Usefulness of gaming as an operational aid in formulating appropriate energy policies worldwide is emphasized. (MBR)

  1. The Current Role of Omega-3 Fatty Acids in the Management of Atrial Fibrillation

    Georgios A. Christou

    2015-09-01

    Full Text Available Background: The main dietary source of omega-3 polyunsaturated fatty acids (n-3 PUFA is fish, which contains eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA. In the present manuscript, we aimed to review the current evidence regarding the clinical role of n-3 PUFA in the prevention of atrial fibrillation (AF and the possible underlying mechanisms. Methods: A literature search based on PubMed listings was performed using “Omega-3 fatty acids” and “atrial fibrilation” as key search terms. Results: n-3 PUFA have been shown to attenuate structural atrial remodeling, prolong atrial effective refractory period through the prevention of reentry and suppress ectopic firing from pulmonary veins. Dietary fish intake has been found to have no effect on the incidence of AF in the majority of studies. Circulating DHA has been consistently reported to be inversely associated with AF risk, whereas EPA has no such effect. The majority of studies investigating the impact of n-3 PUFA supplementation on the incidence of AF following cardiac surgery reported no benefit, though most of them did not use n-3 PUFA pretreatment for adequate duration. Studies using adequate four-week pretreatment with n-3 PUFA before cardioversion of AF showed a reduction of the AF incidence. Conclusions: Although n-3 PUFA have antiarrhythmogenic properties, their clinical efficacy on the prevention of AF is not consistently supported. Further well-designed studies are needed to overcome the limitations of the existing studies and provide robust conclusions.

  2. Integrated soil improvement and agricultural development: why current policy approaches fail

    Koning, N.B.J.; Heerink, N.B.M.; Kauffman, S.

    1997-01-01

    Integrated soil management is an essential condition for agricultural development in West Africa. Such an approach combines improved soil hydraulic measures, organic fertility measures, and inorganic fertilizers and soil amendments. The synergetic effects which result from this combination are indispensable for achieving the productivity increases needed to cope with the increasing pressure of population. Current (neo-liberal and ecological-participationist) policy approaches are unable to re...

  3. New Approaches Towards Recognition of Nucleic Acid Triple Helices

    Arya, Dev P.

    2010-01-01

    We show that groove recognition of nucleic acid triple helices can be achieved with aminosugars. Among these aminosugars, neomycin is the most effective aminoglycoside (groove binder) for stabilizing a DNA triple helix. It stabilizes both the T·A·T triplex and mixed-base DNA triplexes better than known DNA minor groove binders (which usually destabilize the triplex) and polyamines. Neomycin selectively stabilizes the triplex (T·A·T and mixed base) without any effect on the DNA duplex. The sel...

  4. Nucleic Acid-Based Approaches for Detection of Viral Hepatitis

    BEHZADI, Payam; Ranjbar, Reza; Alavian, Seyed Moayed

    2014-01-01

    Context: To determining suitable nucleic acid diagnostics for individual viral hepatitis agent, an extensive search using related keywords was done in major medical library and data were collected, categorized, and summarized in different sections. Results: Various types of molecular biology tools can be used to detect and quantify viral genomic elements and analyze the sequences. These molecular assays are proper technologies for rapidly detecting viral agents with high accuracy, high sensit...

  5. Analytical approach to the current correlation function in dissipative two-state systems

    Qin WANG; Cheng JIANG; Hang ZHENG

    2008-01-01

    Using the spin-boson model with coupling to Ohmic bath, an analytical approach is developed to study the dynamics of the current correlation function in dissipa-tive two-state systems with the view of understanding the ef-fects of environment and tunneling on the coherent oscillation and the long-time decay of the current correlation function in these systems. An analytic expression of current correlation function is obtained and the results agree very well with that of numerical simulations.

  6. Quantum dot as a spin-current diode: A master-equation approach

    Souza, F.M.; Egues, J.C.; Jauho, Antti-Pekka

    2007-01-01

    We report a study of spin-dependent transport in a system composed of a quantum dot coupled to a normal metal lead and a ferromagnetic lead NM-QD-FM. We use the master equation approach to calculate the spin-resolved currents in the presence of an external bias and an intradot Coulomb interaction...

  7. A Critical Analysis of Approaches To Targeted PTSD Prevention: Current Status and Theoretically Derived Future Directions

    Feldner, Matthew T.; Monson, Candice M.; Friedman, Matthew J.

    2007-01-01

    Although efforts to prevent posttraumatic stress disorder (PTSD) have met with relatively limited success, theoretically driven preventive approaches with promising efficacy are emerging. The current article critically reviews investigations of PTSD prevention programs that target persons at risk for being exposed to a traumatic event or who have…

  8. Simple engineering design for complex thermoelectric generators based on reduced current approach

    Wijesooriyage, Waruna Dissanayaka; Rezaniakolaei, Alireza; Rosendahl, Lasse

    2015-01-01

    proposed method predicts the electrical outputs with high accuracies: electrical current with more than 99% accuracy, thermoelectric potential difference with 88-96% accuracy, and power output with 88-96% accuracy. This engineering approach can save significant amount of time and reduce the complexity of...

  9. Review of Current Status and Research Approaches to Nitrogen Pollution in Farmlands

    NIE Sheng-wei; GAO Wang-sheng; CHEN Yuan-quan; SUI Peng; A Egrinya Eneji

    2009-01-01

    In this paper, the history, current status, and research approaches to nitrogen pollution were reviewed using systems analysis and deductions. The seriousness of N pollution world-wide was highlighted and recommendations were made to address the situation. A new hypothesis based on phytoremediation, which means the use of plants to directly or indirectly degrade or remove contaminats from soil and water, was proposed.

  10. Kinetics of oxidation of acidic amino acids by sodium N-bromobenzenesulphonamide in acid medium: A mechanistic approach

    Puttaswamy; Nirmala Vaz

    2001-08-01

    Kinetics of oxidation of acidic amino acids (glutamic acid (Glu) and aspartic acid (Asp)) by sodium N-bromobenzenesulphonamide (bromamine-B or BAB) has been carried out in aqueous HClO4 medium at 30°C. The rate shows firstorder dependence each on [BAB]o and [amino acid]o and inverse first-order on [H+]. At [H+] > 0 60 mol dm-3, the rate levelled off indicating zero-order dependence on [H+] and, under these conditions, the rate has fractional order dependence on [amino acid]. Succinic and malonic acids have been identified as the products. Variation of ionic strength and addition of the reaction product benzenesulphonamide or halide ions had no significant effect on the reaction rate. There is positive effect of dielectric constant of the solvent. Proton inventory studies in H2O-D2O mixtures showed the involvement of a single exchangeable proton of the OH- ion in the transition state. Kinetic investigations have revealed that the order of reactivity is Asp > Glu. The rate laws proposed and derived in agreement with experimental results are discussed.

  11. Microbial production of amino acids and derived chemicals: synthetic biology approaches to strain development.

    Wendisch, Volker F

    2014-12-01

    Amino acids are produced at the multi-million-ton-scale with fermentative production of l-glutamate and l-lysine alone being estimated to amount to more than five million tons in the year 2013. Metabolic engineering constantly improves productivities of amino acid producing strains, mainly Corynebacterium glutamicum and Escherichia coli strains. Classical mutagenesis and screening have been accelerated by combination with intracellular metabolite sensing. Synthetic biology approaches have allowed access to new carbon sources to realize a flexible feedstock concept. Moreover, new pathways for amino acid production as well as fermentative production of non-native compounds derived from amino acids or their metabolic precursors were developed. These include dipeptides, α,ω-diamines, α,ω-diacids, keto acids, acetylated amino acids and ω-amino acids. PMID:24922334

  12. Comparison of two modeling approaches of eddy current industrial non-destructive testing of steel pipes

    Trillon, Adrien; Deneuville, François; Reboud, Christophe; Foucher, Fabrice; Lesselier, Dominique; Maurice, Lea

    2014-02-01

    In the framework of the COFREND working group "Eddy current modeling", a benchmark has been proposed by the Vallourec research center. This case corresponds to the modeling of an industrial online testing of seamless steel pipes by eddy current method with encircling coils. The centering of the steel pipe in the coil is not considered as perfect and a shift is imposed to the pipe. For this benchmark, the Vallourec research center (VRA, Vallourec Research Aulnoye) has compared two solutions with different approaches: the first one is based on semi-analytical methods through the CIVA software developed by the CEA, the second one on finite element method through the software Flux. Results for these two approaches are very similar between them and coherent to experimental data. It proves that these two simulations methods are valid and could be used as a complementary approach.

  13. Analytical approach to pulsed eddy current nondestructive evaluation of multilayered conductive structures

    This paper proposes an analytical approach that can describe the Pulsed Eddy Current Testing (PECT) of stratified conductive structures by a single air coil used for detecting and sizing of metal loss due to interlayer corrosion. Specifically for a single air cored coil above a multilayered conductive structure, the coil impendance response of the cylindrical eddy current probe is calculated based on the truncated region eigenfunction expansion (TREE) method using the generalized matrix coefficients in series form. Analytical modeling of pulsed eddy current is developed using the Fourier series for multilayered conductive structures. A simulation study is carried out for demonstrating the capability of the proposed approach for sizing the metal loss in a two-layer specimen. Furthermore, the experiment is set up to confirm the simulating results of the analytical model for multilayered steels. Good agreement between the theoretical results and measured signals is observed

  14. Challenging the current strategy of radiological protection of the environment: arguments for an ecosystem approach

    Brechignac, F., E-mail: francois.brechignac@irsn. [Institute for Radioprotection and Nuclear Safety (IRSN), Centre d' Etudes de Cadarache, Blg 229, 13115 Saint-Paul-lez-Durance (France); Doi, Masahiro [National Institute of Radiological Sciences, NIRS, Center for Radiation Protection, Regulatory Sciences Research Group, 4-9-1, Anagawa, Inage, Chiba, 263-8555 (Japan)

    2009-12-15

    The system of radiological protection of the environment that is currently under development is one contribution to the general need to adequately protect the environment against stress. Dominated by operational goals, it emphasizes conceptual and methodological approaches that are readily accessible today: reference organisms supported by individual-based traditional ecotoxicological data. Whilst there are immediate advantages to this approach (pragmatism, consistency with other approaches in use for man and biota), there are also clear limitations, especially in a longer run perspective, that need to be acknowledged and further considered. One can mention a few: uncertainties generated by the need for various extrapolations (from lower to higher levels of biological organisation, ...), various features missed such as potential ecological impact through impairment of ecosystem processes, trans-generational impacts as mediated through genomic instability, indirect effects mediated through trophic interactions or disruption of ecological balances, ... Such limitations have already been faced in other fields of environmental protection against other stressors, pushing a number of environment professionals to assign stronger emphasis on more systemic approaches. This review discusses the advantages and limitations of the current approach designed for the radiological protection of non-human biota in the broader context of environment protection as a whole, with especial reference to upcoming trends and evolutions. This leads in particular to advocating the need to boost scientific and methodological approaches featuring the ecosystem concept as a mean to access a unified goal of protection: preserving life sustainability through protection of ecosystem structure and functioning.

  15. Challenging the current strategy of radiological protection of the environment: arguments for an ecosystem approach

    The system of radiological protection of the environment that is currently under development is one contribution to the general need to adequately protect the environment against stress. Dominated by operational goals, it emphasizes conceptual and methodological approaches that are readily accessible today: reference organisms supported by individual-based traditional ecotoxicological data. Whilst there are immediate advantages to this approach (pragmatism, consistency with other approaches in use for man and biota), there are also clear limitations, especially in a longer run perspective, that need to be acknowledged and further considered. One can mention a few: uncertainties generated by the need for various extrapolations (from lower to higher levels of biological organisation, ...), various features missed such as potential ecological impact through impairment of ecosystem processes, trans-generational impacts as mediated through genomic instability, indirect effects mediated through trophic interactions or disruption of ecological balances, ... Such limitations have already been faced in other fields of environmental protection against other stressors, pushing a number of environment professionals to assign stronger emphasis on more systemic approaches. This review discusses the advantages and limitations of the current approach designed for the radiological protection of non-human biota in the broader context of environment protection as a whole, with especial reference to upcoming trends and evolutions. This leads in particular to advocating the need to boost scientific and methodological approaches featuring the ecosystem concept as a mean to access a unified goal of protection: preserving life sustainability through protection of ecosystem structure and functioning.

  16. Current-voltage characteristics of seven-helix proteins from a cubic array of amino acids

    Alfinito, Eleonora; Reggiani, Lino

    2016-06-01

    The electrical properties of a set of seven-helix transmembrane proteins, whose space arrangement [three-dimensional (3D) structure] is known, are investigated by using regular arrays of the amino acids. These structures, specifically cubes, have topological features similar to those shown by the chosen proteins. The theoretical results show a good agreement between the predicted current-voltage characteristics obtained from a cubic array and those obtained from a detailed 3D structure. The agreement is confirmed by available experiments on bacteriorhodopsin. Furthermore, all the analyzed proteins are found to share the same critical behavior of the voltage-dependent conductance and of its variance. In particular, the cubic arrangement evidences a short plateau of the excess conductance and its variance at high voltages. The results of the present investigation show the possibility to predict the I -V characteristics of a multiple-protein sample even in the absence of detailed knowledge of the proteins' 3D structure.

  17. Current techniques in acid-chloride corrosion control and monitoring at The Geysers

    Hirtz, Paul; Buck, Cliff; Kunzman, Russell

    1991-01-01

    Acid chloride corrosion of geothermal well casings, production piping and power plant equipment has resulted in costly corrosion damage, frequent curtailments of power plants and the permanent shut-in of wells in certain areas of The Geysers. Techniques have been developed to mitigate these corrosion problems, allowing continued production of steam from high chloride wells with minimal impact on production and power generation facilities.The optimization of water and caustic steam scrubbing, steam/liquid separation and process fluid chemistry has led to effective and reliable corrosion mitigation systems currently in routine use at The Geysers. When properly operated, these systems can yield steam purities equal to or greater than those encountered in areas of The Geysers where chloride corrosion is not a problem. Developments in corrosion monitoring techniques, steam sampling and analytical methodologies for trace impurities, and computer modeling of the fluid chemistry has been instrumental in the success of this technology.

  18. Photodynamic therapy using 5-aminolevulinic acid-induced photosensitization: current clinical status

    Marcus, Stuart L.; Golub, Allyn L.; Shulman, D. Geoffrey

    1995-03-01

    Photodynamic therapy using 5-aminolevulinic acid-induced photosensitization (ALA PDT) via endogenous protoporphyrin IX (PpIX) synthesis has been reported as efficacious, using topical formulations, in the treatment of a variety of dermatologic diseases including superficial basal cell carcinoma, Bowen's disease, and actinic (solar) keratoses. Application of ALA PDT to the detection and treatment of both malignant and non-malignant diseases of internal organs has recently been reported. Local internal application of ALA has been used for the detection, via PpIX fluorescence, of pathological conditions of the human urinary bladder and for selective endometrial ablation in animal model systems. Systemic, oral administration of ALA has been used for ALA PDT of superficial head and neck cancer and of colorectal cancer. This paper reviews the current clinical status of ALA PDT.

  19. Radiation dose calculations for CT scans with tube current modulation using the approach to equilibrium function

    Purpose: The approach to equilibrium function has been used previously to calculate the radiation dose to a shift-invariant medium undergoing CT scans with constant tube current [Li, Zhang, and Liu, Med. Phys. 39, 5347–5352 (2012)]. The authors have adapted this method to CT scans with tube current modulation (TCM). Methods: For a scan with variable tube current, the scan range was divided into multiple subscan ranges, each with a nearly constant tube current. Then the dose calculation algorithm presented previously was applied. For a clinical CT scan series that presented tube current per slice, the authors adopted an efficient approach that computed the longitudinal dose distribution for one scan length equal to the slice thickness, which center was at z = 0. The cumulative dose at a specific point was a summation of the contributions from all slices and the overscan. Results: The dose calculations performed for a total of four constant and variable tube current distributions agreed with the published results of Dixon and Boone [Med. Phys. 40, 111920 (14pp.) (2013)]. For an abdomen/pelvis scan of an anthropomorphic phantom (model ATOM 701-B, CIRS, Inc., VA) on a GE Lightspeed Pro 16 scanner with 120 kV, N × T = 20 mm, pitch = 1.375, z axis current modulation (auto mA), and angular current modulation (smart mA), dose measurements were performed using two lines of optically stimulated luminescence dosimeters, one of which was placed near the phantom center and the other on the surface. Dose calculations were performed on the central and peripheral axes of a cylinder containing water, whose cross-sectional mass was about equal to that of the ATOM phantom in its abdominal region, and the results agreed with the measurements within 28.4%. Conclusions: The described method provides an effective approach that takes into account subject size, scan length, and constant or variable tube current to evaluate CT dose to a shift-invariant medium. For a clinical CT scan

  20. A review on the current status and production technology of 32,33P-orthophosphoric acid

    The current status of 32, 33P-Orthophosphoric acid production technology is reviewed. The following aspects of the technology are covered: - production of phosphorus-32 and phosphorus-33 using various nuclear reactions; - chemical properties of sulfur and phosphorus effecting the technology of radioactive phosphorus production; - chemical state of 32, 33P in neutron irradiated sulfur; - the technology of radioactive phosphorus isolation from neutron irradiated target and orthophosphoric acid production; - purification of 32, 33P-orthophosphoric acid from impurities and some related problems, like the nature of impurities, the storage of the final product, etc. - the quality control procedures of carrier-free (32, 33P)-orthophosphoric acid preparations

  1. Conformational basis for the Li(+)-induced leak current in the rat gamma-aminobutyric acid (GABA) transporter-1

    MacAulay, Nanna; Zeuthen, Thomas; Gether, Ulrik

    The rat gamma-aminobutyric acid transporter-1 (GAT-1) was expressed in Xenopus laevis oocytes and the substrate-independent Li(+)-induced leak current was examined using two-electrode voltage clamp. The leak current was not affected by the addition of GABA and was not due to H(+) permeation. The Li...

  2. Modulation of voltage-dependent Ca channel current by arachidonic acid and other long-chain fatty acids in rabbit intestinal smooth muscle

    1992-01-01

    The effects of arachidonic acid (AA) and other long-chain fatty acids on voltage-dependent Ca channel current (ICa) were investigated, with the whole cell patch clamp method, in longitudinal smooth muscle cells of rabbit ileum. 10-30 microM AA caused a gradual depression of ICa. The inhibitory effect of AA was not prevented by indomethacin (10 microM) (an inhibitor of cyclooxygenase) or nordihydroguaiaretic acid (10 microM) (an inhibitor of lipoxygenase). 1-(5-Isoquinolinesulfonyl)- 2-methylp...

  3. Introducing a Student-centred Learning Approach in Current Curriculum Reform in Mozambican Higher Education

    Mendonça, Marta; Popov, Oleg; Frånberg, Gun-Marie; Cossa, Eugénia

    2012-01-01

    The Eduardo Mondlane University (UEM) in Mozambique is introducing new participative forms of pedagogical practices into the process of its current curriculum reform. This article presents a case study of the introduction of a student-centred approach at one department and discusses some of the lecturers’ perceptions and experiences concerning the process. A qualitative study was carried out based on classroom observations and interviews. Activity theory was used in the analysis of the result...

  4. Formulation approaches to pediatric oral drug delivery: benefits and limitations of current platforms

    Lopez, F.L. (Faye L.); Ernest, T. B.; Tuleu, C.; Gul, M. O.

    2015-01-01

    INTRODUCTION: Most conventional drug delivery systems are not acceptable for pediatric patients as they differ in their developmental status and dosing requirements from other subsets of the population. Technology platforms are required to aid the development of age-appropriate medicines to maximize patient acceptability while maintaining safety, efficacy, accessibility and affordability. AREAS COVERED: The current approaches and novel developments in the field of age-appropriate drug deliver...

  5. Marketing of library and information services in global era: A current approach

    Sanjay Kumar Karn; Basanta Kumar Das

    2008-01-01

    This paper deals with the marketing of library and information services in the global era. It discusses about the marketing concept of today's library and information centers covering various topics such as management of libraries and commitment to customer's satisfaction. It also defines the marketing and its current approach to library and information services at the global level. It also describes customer/user's topic such as customers' priorities, customers' expectations, individuality r...

  6. Modern Measurement Approaches to Health Literacy Scale Development and Refinement: Overview, Current Uses, and Next Steps.

    Nguyen, Tam H; Paasche-Orlow, Michael K; Kim, Miyong T; Han, Hae-Ra; Chan, Kitty S

    2015-01-01

    There are currently more than 100 health literacy instruments. The procedures used to develop and test the measures are primarily guided by classical test theory. However, a small and growing number (n = 13) of health literacy measures are guided by modern measurement theories such as item response theory. This article briefly describes (a) the benefits of using modern measurement approaches for the development of health literacy measures, (b) how these approaches have been used with existing health literacy measures, and (c) some considerations for how modern measurement theory can help strengthen future work in health literacy measurement. Ultimately, this article provides evidence to support an assertive shift toward the use of modern measurement approaches in health literacy instrument development. PMID:26513038

  7. COLON SPECIFIC DRUG DELIVERY SYSTEMS: A REVIEW ON PHARMACEUTICAL APPROACHES WITH CURRENT TRENDS

    Komaragiri Keerthi

    2012-07-01

    Full Text Available In recent years colon specific drug delivery has gained importance not just for the delivery of drugs for the treatment of local diseases associated with the colon but also as potential site for the systemic delivery of drugs like therapeutic proteins and peptides. This article reviews a detailed study about diseases of colon, diagnosis of diseases of colon, limitations and challenges, applications, anatomy of colon, factors affecting colon and different approaches of colon which include some current new approaches such as Pulsinicap system, Port system, Probiotic approach, Chronotropic system, Colal-pred system, Multiparticulate system, Enterion capsule technology and some past studies of colon drug delivery and also a study on evaluation for site specific drug delivery to colon.

  8. A frequency domain approach to analyzing passive battery-ultracapacitor hybrids supplying periodic pulsed current loads

    Highlights: → Passive battery-ultracapacitor hybrids are examined. → Frequency domain analysis is employed. → The ultracapacitor branch operates as a low-pass filter for the battery. → The battery supplies the average load demand. → Design requirements are discussed. - Abstract: A Fourier-based analysis of passive battery-ultracapacitor hybrid sources is introduced in the manuscript. The approach is first introduced for a general load, and then is followed by a study for a case of periodic pulsed current load. It is shown that the ultracapacitor branch is perceived by the battery as a low-pass filter, which absorbs the majority of the high frequency harmonic current and letting the battery to supply the average load demand in addition to the small part of dynamic current. Design requirements influence on the ultracapacitor capacitance and internal resistance choice are quantitatively discussed. The theory is enforced by simulation and experimental results, showing an excellent agreement.

  9. A frequency domain approach to analyzing passive battery-ultracapacitor hybrids supplying periodic pulsed current loads

    Kuperman, Alon, E-mail: alonku@ariel.ac.il [Hybrid Energy Sources Center, Dept. of Electrical Engineering and Electronics, Ariel University Center, Kiryat Hamada, Ariel 40700 (Israel); Aharon, Ilan; Kara, Avi; Malki, Shalev [Hybrid Energy Sources Center, Dept. of Electrical Engineering and Electronics, Ariel University Center, Kiryat Hamada, Ariel 40700 (Israel)

    2011-11-15

    Highlights: {yields} Passive battery-ultracapacitor hybrids are examined. {yields} Frequency domain analysis is employed. {yields} The ultracapacitor branch operates as a low-pass filter for the battery. {yields} The battery supplies the average load demand. {yields} Design requirements are discussed. - Abstract: A Fourier-based analysis of passive battery-ultracapacitor hybrid sources is introduced in the manuscript. The approach is first introduced for a general load, and then is followed by a study for a case of periodic pulsed current load. It is shown that the ultracapacitor branch is perceived by the battery as a low-pass filter, which absorbs the majority of the high frequency harmonic current and letting the battery to supply the average load demand in addition to the small part of dynamic current. Design requirements influence on the ultracapacitor capacitance and internal resistance choice are quantitatively discussed. The theory is enforced by simulation and experimental results, showing an excellent agreement.

  10. Current Progress and Future Research on the Production of Oxygenated Fatty Acids

    Oxygenated (hydroxy-, epoxy-) fatty acids such as ricinoleic, vernolic and /or sebacic acids are high value chemicals and can be used to produce polymers and specialty chemicals. Oxygenated fatty acids also have many bioactive properties, such as antimicrobial activity against Salmonella, Staphyloc...

  11. A synthetic approach to carbon-14 labeled anti-bacterial naphthyridine and quinolone carboxylic acids

    Ekhato, I.V.; Huang, C.C. (Parke, Davis and Co., Ann Arbor, MI (United States))

    1993-09-01

    Labeled versions of (S)-clinafloxacin (1) and two napththyridine carboxylic acid anti-bacterial compounds 2 and 3 which are currently in development were synthesized. Preparations started from hitherto unknown bromo compounds 22 and 10, from which the corresponding [sup 14]C-labeled aromatic carboxylic acids 23 and 12 were generated by metal-halogen exchange followed by carboxylation reaction. Details of these preparations are given. (author).

  12. Current status and emerging role of glutathione in food grade lactic acid bacteria

    Pophaly Sarang

    2012-08-01

    Full Text Available Abstract Lactic acid bacteria (LAB have taken centre stage in perspectives of modern fermented food industry and probiotic based therapeutics. These bacteria encounter various stress conditions during industrial processing or in the gastrointestinal environment. Such conditions are overcome by complex molecular assemblies capable of synthesizing and/or metabolizing molecules that play a specific role in stress adaptation. Thiols are important class of molecules which contribute towards stress management in cell. Glutathione, a low molecular weight thiol antioxidant distributed widely in eukaryotes and Gram negative organisms, is present sporadically in Gram positive bacteria. However, new insights on its occurrence and role in the latter group are coming to light. Some LAB and closely related Gram positive organisms are proposed to possess glutathione synthesis and/or utilization machinery. Also, supplementation of glutathione in food grade LAB is gaining attention for its role in stress protection and as a nutrient and sulfur source. Owing to the immense benefits of glutathione, its release by probiotic bacteria could also find important applications in health improvement. This review presents our current understanding about the status of glutathione and its role as an exogenously added molecule in food grade LAB and closely related organisms.

  13. Distributions of 12 elements on 64 absorbers from simulated Hanford Neutralized Current Acid Waste (NCAW)

    As part of the Hanford Tank Waste Remediation System program at Los Alamos, we evaluated 64 commercially available or experimental absorber materials for their ability to remove hazardous components from high-level waste. These absorbers included cation and anion exchange resins, inorganic exchangers, composite absorbers, and a series of liquid extractants sorbed on porous support-beads. We tested these absorbers with a solution that simulates Hanford neutralized current acid waste (NCAW) (pH 14.2). To this simulant solution we added the appropriate radionuclides and used gamma spectrometry to measure fission products (Cs, Sr, Tc, and Y) and matrix elements (Cr, Co, Fe, Mn, Ni, V, Zn, and Zr). For each of 768 element/absorber combinations, we measured distribution coefficients for dynamic contact periods of 30 min, 2 h, and 6 h to obtain information about sorption kinetics. On the basis of these 2304 measured distribution coefficients, we determined that many of the tested absorbers may be suitable for processing NCAW solutions

  14. Process Design Report for Wood Feedstock: Lignocellulosic Biomass to Ethanol Process Desing and Economics Utilizing Co-Current Dilute Acid Prehydrolysis and Enzymatic Hydrolysis Current and Futuristic Scenarios

    Wooley, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ruth, Mark [National Renewable Energy Lab. (NREL), Golden, CO (United States); Sheehan, John [National Renewable Energy Lab. (NREL), Golden, CO (United States); Ibsen, Kelly [National Renewable Energy Lab. (NREL), Golden, CO (United States); Majdeski, Henry [Delta-T Corporation, Lexington, KY (United States); Galves, Adrian [Delta-T Corporation, Lexington, KY (United States)

    1999-07-01

    The National Renewable Energy Laboratory (NREL) has undertaken a complete review and update of the process design and economic model for the biomass-to-ethanol process based on co-current dilute acid prehydrolysis, along with simultaneous saccharification (enzymatic) and co-fermentation. The process design includes the core technologies being researched by the U.S. Department of Energy (DOE): prehydrolysis, simultaneous saccharification and co-fermentation, and cellulase enzyme production.

  15. Simulation of the current distribution in lead-acid batteries to investigate the dynamic charge acceptance in flooded SLI batteries

    Kowal, Julia; Schulte, Dominik; Sauer, Dirk Uwe [Electrochemical Energy Conversion and Storage Systems Group, Institute for Power Electronics and Electrical Drives (ISEA), RWTH Aachen University, 52066 Aachen (Germany); Karden, Eckhard [Ford Research and Advanced Engineering Europe, Aachen (Germany)

    2009-06-01

    Measurements show that the dynamic charge acceptance (DCA) of flooded SLI lead-acid batteries during micro-cycling in conventional and micro-hybrid vehicles is strongly dependent on the short-term history, such as previous charge or discharge, current rate, lowest state of charge in the last 24 h and more. Factors of 10 have been reported. Inhomogeneous current distribution, especially as a result of acid stratification, has been suggested to explain the DCA variability. This hypothesis was investigated by simulation of a two-dimensional macrohomogeneous model. It provides a spatial resolution of three elements in horizontal direction in each electrode and three elements in vertical direction. For an existing set of parameters, different current profiles were analyzed with regard to the current distribution during charging and discharging. In these simulations, a strong impact of the short-term history on current, charge and acid density distribution was found as well as a strong influence of micro-cycles on both charge distribution and acid stratification. (author)

  16. Continuum random phase approximation approach to charged-current neutrino-nucleus scattering

    We present continuum random phase approximation (CRPA) calculations for charged-current neutrino-nucleus scattering. The CRPA formalism is based on a Green's-function approach, and the calculations can be done in a self-consistent fashion when using an effective nucleon-nucleon force of the Skyrme type. We analyze the technical aspects related to the description of charge-exchange reactions within this approach, and study the sensitivity of the results to the single-particle characteristics of the formalism. Muon capture is studied as a test case. In applications of the formalism, we concentrate on neutrino-scattering off 12C and 16O, and pay attention to interactions of experimental interest

  17. Modelling of eddy-current interaction with cracks in the thin-skin regime. Two approaches

    EDF uses TRIFOU code for eddy current testing modelling. This general electromagnetic code is to be further adapted to Non Destructive Testing applications, not only for nuclear NDT but also in other fields such as aeronautical. This paper compares experimental data for aluminium and steel specimens with two methods of solving the forward problem in the thin-skin regime. The first approach is a 3D Finite Element / Boundary Integral Element method (TRIFOU) developed by EDF/RD Division (France). The second approach is specialized for the treatment of surface cracks in the thin-skin regime developed by the University of Surrey (England). In the thin-skin regime, the electromagnetic skin-depth is small compared with the depth of the crack. Such conditions are common in tests on steels and sometimes on aluminium. (K.A.)

  18. Charged-current neutrino-nucleus reactions within the SuSAv2-MEC approach

    Megias, G D; Barbaro, M B; Caballero, J A; Donnelly, T W; Simo, I Ruiz

    2016-01-01

    We present a detailed study of charged-current (CC) neutrino-nucleus reactions in a fully relativis- tic framework and comparisons with recent experiments spanning an energy range from hundreds of MeV up to 100 GeV within the SuperScaling Approach, which is based on the analysis of electron- nucleus scattering data and has been recently improved with the inclusion of Relativistic Mean Field theory effects. We also evaluate and discuss the impact of two-particle two-hole meson-exchange currents (2p-2h MEC) on neutrino-nucleus interactions through the analysis of two-particle two-hole axial and vector contributions to weak response functions in a fully relativistic Fermi gas. The results show a fairly good agreement with experimental data over the whole range of neutrino energies.

  19. Variational approach to low-frequency kinetic-MHD in the current coupling scheme

    Burby, J W

    2016-01-01

    Hybrid kinetic-MHD models describe the interaction of an MHD bulk fluid with an ensemble of hot particles, which is described by a kinetic equation. When the Vlasov description is adopted for the energetic particles, different Vlasov-MHD models have been shown to lack an exact energy balance, which was recently recovered by the introduction of non-inertial force terms in the kinetic equation. These force terms arise from fundamental approaches based on Hamiltonian and variational methods. In this work we apply Hamilton's variational principle to formulate new current-coupling kinetic-MHD models in the low-frequency approximation (i.e. large Larmor frequency limit). More particularly, we formulate current-coupling hybrid schemes, in which energetic particle dynamics are expressed in either guiding-center or gyrocenter coordinates.

  20. Effects of unsaturated fatty acids on calcium-activated potassium current in gastric myocytes of guinea pigs

    Hai-Feng Zheng; Xiang-Lan Li; Zheng-Yuan Jin; Jia-Bin Sun; Zai-Liu Li; Wen-Xie Xu

    2005-01-01

    AIM: To investigate the effects of exogenous unsaturated fatty acids on calcium-activated potassium current [Ik(Ca)]in gastric antral circular myocytes of guinea pigs.METHODS: Gastric myocytes were isolated by collagenase from the antral circular layer of guinea pig stomach. The whole-cell patch clamp technique was used to record Ik(Ca)in the isolated single smooth muscle cells with or without different concentrations of arachidonic acid (AA), linoleic acid (LA), and oleic acid (OA).RESULTS: AA at concentrations of 2,5 and 10 μmol/L markedly increased IK(ca)in a dose-dependent manner. LA at concentrations of 5, 10 and 20 μmol/L also enhanced IK(Ca)in a dose-dependent manner. The increasing potency of AA, LA, and oleic acid (OA) on Ik(Ca) at the same concentration(10 μmol/L) was in the order of AA>LA>OA. AA (10 μmol/L)-induced increase of Ik(Ca) was not blocked by H-7 (10 μmol/L), an inhibitor of protein kinase C (PKC), or indomethacin (10 μmol/L),an inhibitor of the cyclooxygenase pathway, and 17-octadecynoic acid (10 μmol/L), an inhibitor of the cytochrome P450 pathway, but weakened by nordihydroguaiaretic acid(10 μmol/L), an inhibitor of the lipoxygenase pathway.CONCLUSION: Unsaturated fatty acids markedly increase Ik(Ca), and the enhancing potencies are related to the number of double bonds in the fatty acid chain. The lipoxygenase pathway of unsaturated fatty acid metabolism is involved in the unsaturated fatty acid-induced increase of IK(Ca) in gastric antral circular myocytes of guinea pigs.

  1. Time of flight mass spectroscopy, a modern approach to current methods of solid analysis

    Mass spectrography has been a current method for trace analysis in solids, with spark source or laser probe, but photoplate is no more a convenient detector; in a contrast, time of flight mass spectrometry, capable of recording all the ions emitted in only one swarm, allows data acquisition to be performed on line by a computer. The electro-optical detector of Eloy and Unsold brings to mass spectrography the time of flight technics. The results obtained with a single focusing instrument are discussed in terms of ion optics, and a theoretical approach to spark source mass spectrograph is presented showing that the performances depend on the ion source properties

  2. B→K Transition Form Factor with Tensor Current within the kT Factorization Approach

    ZENG Dai-Min; WU Xing-Gang; FANG Zhen-Yun

    2008-01-01

    We apply the kT factorization approach to deal with the B→K transition form factor with tensor current in the large recoil regions.Main uncertainties for the estimation are discussed and we obtain FBT→k(0)=0.25±0.01±0.02,where the first error is caused by the uncertainties from the pionic wavefunctions and the second js from that of the B-mean wavefunctions.This result is consistent with the light-cone sum rule results obtained in the literature.

  3. Approach to make macroporous metal sheets as current collectors for lithium-ion batteries

    Xu, Wu; Canfield, Nathan L.; Wang, Deyu; Xiao, Jie; Nie, Zimin; Li, Xiaohong S.; Bennett, Wendy D.; Bonham, Charles C.; Zhang, Jiguang

    2010-05-05

    A new approach and simple method is described to produce macroporous metal sheet as current collector for anode in lithium ion battery. This method, based on slurry blending, tape casting, sintering, and reducing of metal oxides, produces a uniform, macroporous metal sheet. Silicon film sputter-coated on such porous copper substrate shows much higher capacity and longer cycle life than on smooth Cu foil. This methodology produces very limited wastes and is also adaptable to many other materials. It is easy for industrial scale production.

  4. Microalgal biofactories: a promising approach towards sustainable omega-3 fatty acid production

    Adarme-Vega T

    2012-07-01

    Full Text Available Abstract Omega-3 fatty acids eicosapentaenoic acid (EPA and docosahexaenoic acid (DHA provide significant health benefits and this has led to an increased consumption as dietary supplements. Omega-3 fatty acids EPA and DHA are found in animals, transgenic plants, fungi and many microorganisms but are typically extracted from fatty fish, putting additional pressures on global fish stocks. As primary producers, many marine microalgae are rich in EPA (C20:5 and DHA (C22:6 and present a promising source of omega-3 fatty acids. Several heterotrophic microalgae have been used as biofactories for omega-3 fatty acids commercially, but a strong interest in autotrophic microalgae has emerged in recent years as microalgae are being developed as biofuel crops. This paper provides an overview of microalgal biotechnology and production platforms for the development of omega-3 fatty acids EPA and DHA. It refers to implications in current biotechnological uses of microalgae as aquaculture feed and future biofuel crops and explores potential applications of metabolic engineering and selective breeding to accumulate large amounts of omega-3 fatty acids in autotrophic microalgae.

  5. Current experience with applying the GRADE approach to public health interventions: an empirical study

    Rehfuess Eva A

    2013-01-01

    Full Text Available Abstract Background The Grading of Recommendations Assessment, Development and Evaluation (GRADE approach has been adopted by many national and international organisations as a systematic and transparent framework for evidence-based guideline development. With reference to an ongoing debate in the literature and within public health organisations, this study reviews current experience with the GRADE approach in rating the quality of evidence in the field of public health and identifies challenges encountered. Methods We conducted semi-structured interviews with individuals/groups that have applied the GRADE approach in the context of systematic reviews or guidelines in the field of public health, as well as with representatives of groups or organisations that actively decided against its use. We initially contacted potential participants by email. Responses were obtained by telephone interview or email, and written interview summaries were validated with participants. We analysed data across individual interviews to distil common themes and challenges. Results Based on 25 responses, we undertook 18 interviews and obtained 15 in-depth responses relating to specific systematic reviews or guideline projects; a majority of the latter were contributed by groups within the World Health Organization. All respondents that have used the GRADE approach appreciated the systematic and transparent process of assessing the quality of the evidence. However, respondents reported a range of minor and major challenges relating to complexity of public health interventions, choice of outcomes and outcome measures, ability to discriminate between different types of observational studies, use of non-epidemiological evidence, GRADE terminology and the GRADE and guideline development process. Respondents’ suggestions to make the approach more applicable to public health interventions included revisiting terminology, offering better guidance on how to apply GRADE to

  6. Current approaches of the management of mercury poisoning: need of the hour.

    Rafati-Rahimzadeh, Mehrdad; Rafati-Rahimzadeh, Mehravar; Kazemi, Sohrab; Moghadamnia, Ali Akbar

    2014-01-01

    Mercury poisoning cases have been reported in many parts of the world, resulting in many deaths every year. Mercury compounds are classified in different chemical types such as elemental, inorganic and organic forms. Long term exposure to mercury compounds from different sources e.g. water, food, soil and air lead to toxic effects on cardiovascular, pulmonary, urinary, gastrointestinal, neurological systems and skin. Mercury level can be measured in plasma, urine, feces and hair samples. Urinary concentration is a good indicator of poisoning of elemental and inorganic mercury, but organic mercury (e.g. methyl mercury) can be detected easily in feces. Gold nanoparticles (AuNPs) are a rapid, cheap and sensitive method for detection of thymine bound mercuric ions. Silver nanoparticles are used as a sensitive detector of low concentration Hg2+ ions in homogeneous aqueous solutions. Besides supportive therapy, British anti lewisite, dimercaprol (BAL), 2,3-dimercaptosuccinic acid (DMSA. succimer) and dimercaptopropanesulfoxid acid (DMPS) are currently used as chelating agents in mercury poisoning. Natural biologic scavengers such as algae, azolla and other aquatic plants possess the ability to uptake mercury traces from the environment. PMID:24888360

  7. Synchronized Current Oscillations of Formic Acid Electro-oxidation in a Microchip-based Dual-Electrode Flow Cell

    Kiss, István Z.; Munjal, Neil; Martin, R. Scott

    2009-01-01

    We investigate the oscillatory electro-oxidation of formic acid on platinum in a microchip-based dual-electrode cell with microfluidic flow control. The main dynamical features of current oscillations on single Pt electrode that had been observed in macro-cells are reproduced in the microfabricated electrochemical cell. In dual-electrode configuration nearly in-phase synchronized current oscillations occur when the reference/counter electrodes are placed far away from the microelectrodes. The...

  8. Structure and tautomerism of tenuazonic acid – A synergetic computational and spectroscopic approach

    Highlights: ► Many published structures for tenuazonic acid (TeA) are incorrect. ► DFT calculations were used for quantum chemical treatment of tenuazonic acid. ► This article reports the confirmation of the main tautomeric structures of TeA. ► A synergetic computational and spectroscopic approach was applied. -- Abstract: All reasonable tautomers and rotamers of tenuazonic acid, which is considered to be of the highest toxicity amongst the Alternaria mycotoxins, were investigated by DFT calculations at different levels of theory in gas phase and in solution to obtain optimized geometries for further examinations. Calculated NMR spectra of tautomeric structures are being presented and compared to experimental data to finally achieve a synergetic computational and spectroscopic approach for structure elucidation of 3-acetyltetramic acids, affording the predominant tautomer of tenuazonic acid in aqueous solution. Furthermore we were able to simulate the less hindered rotation of the exocyclic acetyl group, which occurs after dissociation of tenuazonic acid in protic solvents

  9. Structure and tautomerism of tenuazonic acid – A synergetic computational and spectroscopic approach

    Mikula, Hannes, E-mail: hannes.mikula@tuwien.ac.at [Vienna University of Technology, Institute of Applied Synthetic Chemistry, Getreidemarkt 9/163-OC, 1060 Vienna (Austria); University of Natural Resources and Life Sciences, Institute of Applied Genetics and Cell Biology, Muthgasse 18, 1190 Wien (Austria); Horkel, Ernst; Hans, Philipp; Hametner, Christian; Fröhlich, Johannes [Vienna University of Technology, Institute of Applied Synthetic Chemistry, Getreidemarkt 9/163-OC, 1060 Vienna (Austria)

    2013-04-15

    Highlights: ► Many published structures for tenuazonic acid (TeA) are incorrect. ► DFT calculations were used for quantum chemical treatment of tenuazonic acid. ► This article reports the confirmation of the main tautomeric structures of TeA. ► A synergetic computational and spectroscopic approach was applied. -- Abstract: All reasonable tautomers and rotamers of tenuazonic acid, which is considered to be of the highest toxicity amongst the Alternaria mycotoxins, were investigated by DFT calculations at different levels of theory in gas phase and in solution to obtain optimized geometries for further examinations. Calculated NMR spectra of tautomeric structures are being presented and compared to experimental data to finally achieve a synergetic computational and spectroscopic approach for structure elucidation of 3-acetyltetramic acids, affording the predominant tautomer of tenuazonic acid in aqueous solution. Furthermore we were able to simulate the less hindered rotation of the exocyclic acetyl group, which occurs after dissociation of tenuazonic acid in protic solvents.

  10. Robert Feulgen Prize Lecture 1995. New approaches to in situ detection of nucleic acids.

    Thiry, M

    1995-08-01

    The present paper reviews recent results obtained by different molecular biology-based, immunocytological approaches to the localization and identification of nucleic acids in sections of biological material. Examples of sensitive, high-resolution detection methods for RNA, DNA or specialized DNA regions are presented. Special emphasis is placed on the potential values and limitations of these new methods. PMID:8536076

  11. What are humic substances? : a molecular approach to the study of organic matter in acid soils

    Naafs, Derck Ferdinand Werner

    2004-01-01

    Molecular studies on the composition of organic matter in soils are scarce. In this thesis, a molecular approach to the study of organic matter in acid soils is presented, with a focus on andic, i.e. volcanic, soils. Analyses include both chemical extractions as well as pyrolysis-GC/MS and CPMAS 13C

  12. Early results from a systems approach to improving the performance and lifetime of lead acid batteries

    Kellaway, M. J.; Jennings, P.; Stone, D.; Crowe, E.; Cooper, A.

    Lead acid batteries offer important advantages in respect of unit cost and ease of recycling. They also have good power and low temperature performance. However, for hybrid electric vehicle (HEV) duty with their extreme rates and continuous PSoC operation, improvements are required to significantly extend service life. The Reliable Highly Optimised Lead Acid Battery (RHOLAB) project is taking a radical approach to the design of a lead acid HEV battery pack to address this issue, taking a systems approach to produce a complete pack that is attractive to vehicle manufacturers. This paper describes the project at an intermediate stage where some testing has been completed and the construction of the complete pack system is well under way.

  13. Fracture and electric current in the crust: a q-statistical approach

    Cartwright-Taylor, A. L.; Vallianatos, F.; Sammonds, P. R.

    2013-12-01

    We have conducted room-temperature, triaxial compression experiments on samples of Carrara marble, recording concurrently acoustic and electric current signals emitted during deformation as well as mechanical loading information and ultrasonic wave velocities. Our results reveal that, in a non-piezoelectric rock under simulated crustal conditions, a measurable and increasing electric current (nA) is generated within the stressed sample in the region beyond (quasi-)linear elastic deformation; i.e. in the region of permanent deformation beyond the yield point of the material and in the presence of microcracking. This has implications for the earthquake preparation process. Our results extend to shallow crustal conditions previous observations of electric current signals in quartz-free rocks undergoing uniaxial deformation, supporting the idea of a universal electrification mechanism related to deformation; a number of which have been proposed. Confining pressure conditions of our slow strain rate experiments range from the purely brittle regime to the semi-brittle transition where cataclastic flow is the dominant deformation mechanism. Electric current evolution under these two confining pressures shows some markedly different features, implying the existence of a current-producing mechanism during both microfracture and frictional sliding, possibly related to crack localisation. In order to analyse these 'pressure-stimulated' electric currents, we adopt an entropy-based non-extensive statistical physics approach that is particularly suited to the study of fracture-related phenomena. In the presence of a long timescale (hours) external driving force (i.e. loading), the measured electric current exhibits transient, nonstationary behaviour with strong fluctuations over short timescales (seconds); calmer periods punctuated by bursts of strong activity. We find that the probability distribution of normalised electric current fluctuations over short time intervals (0.5s

  14. An adaptive mesh refinement approach for average current nodal expansion method in 2-D rectangular geometry

    Highlights: ► A new adaptive h-refinement approach has been developed for a class of nodal method. ► The resulting system of nodal equations is more amenable to efficient numerical solution. ► The benefit of the approach is reducing computational efforts relative to the uniform fine mesh modeling. ► Spatially adaptive approach greatly enhances the accuracy of the solution. - Abstract: The aim of this work is to develop a spatially adaptive coarse mesh strategy that progressively refines the nodes in appropriate regions of domain to solve the neutron balance equation by zeroth order nodal expansion method. A flux gradient based a posteriori estimation scheme has been utilized for checking the approximate solutions for various nodes. The relative surface net leakage of nodes has been considered as an assessment criterion. In this approach, the core module is called in by adaptive mesh generator to determine gradients of node surfaces flux to explore the possibility of node refinements in appropriate regions and directions of the problem. The benefit of the approach is reducing computational efforts relative to the uniform fine mesh modeling. For this purpose, a computer program ANRNE-2D, Adaptive Node Refinement Nodal Expansion, has been developed to solve neutron diffusion equation using average current nodal expansion method for 2D rectangular geometries. Implementing the adaptive algorithm confirms its superiority in enhancing the accuracy of the solution without using fine nodes throughout the domain and increasing the number of unknown solution. Some well-known benchmarks have been investigated and improvements are reported

  15. Anodized aluminum on LDEF: A current status of measurements on chromic acid anodized aluminum

    Golden, Johnny L.

    1992-01-01

    Chromic acid anodize was used as the exterior coating for aluminum surfaces on LDEF to provide passive thermal control. Chromic acid anodized aluminum was also used as test specimens in thermal control coatings experiments. The following is a compilation and analysis of the data obtained thus far.

  16. Anodized aluminum on LDEF: A current status of measurements on chromic acid anodized aluminum

    Chromic acid anodize was used as the exterior coating for aluminum surfaces on LDEF to provide passive thermal control. Chromic acid anodized aluminum was also used as test specimens in thermal control coatings experiments. The following is a compilation and analysis of the data obtained thus far

  17. A review on the current status and production technology of {sup 32,} {sup 33}P-orthophosphoric acid

    Park, Ul Jae; Han, Hyun Soo; Cho, Woon Kap; Kuznetsov, Rostislav A

    2000-10-01

    The current status of {sup 32}, {sup 33}P-Orthophosphoric acid production technology is reviewed. The following aspects of the technology are covered: - production of phosphorus-32 and phosphorus-33 using various nuclear reactions; - chemical properties of sulfur and phosphorus effecting the technology of radioactive phosphorus production; - chemical state of {sup 32}, {sup 33}P in neutron irradiated sulfur; - the technology of radioactive phosphorus isolation from neutron irradiated target and orthophosphoric acid production; - purification of {sup 32}, {sup 33}P-orthophosphoric acid from impurities and some related problems, like the nature of impurities, the storage of the final product, etc. - the quality control procedures of carrier-free ({sup 32}, {sup 33}P)-orthophosphoric acid preparations.

  18. Isolation of chlorogenic acid from Mutellina purpurea L. herb using high-performance counter-current chromatography.

    Sieniawska, Elwira; Skalicka-Woźniak, Krystyna

    2014-01-01

    The aim of the study was to explore proper isolation conditions of chlorogenic acid from the herb of Mutelina purpurea L. - a new source of this bioactive molecule. The accelerated solvent extraction (ASE) with 40% aqueous solution of methanol combined with high-performance counter-current chromatography (HPCCC) was utilised for the efficient extraction and the separation of chlorogenic acid from the M. purpurea herb in less than 30 min. The structure of the obtained compound was confirmed by mass spectrometry and NMR analysis. The preparative HPCCC was performed using the mixture of ethyl acetate, butanol and water (4:1:5, v/v/v) in the reverse-phase mode. The chlorogenic acid was isolated from this herb for the first time, yielding 96% purity. The ASE with 40% methanol combined with HPCCC separation was proven to be a useful tool for quick and efficient isolation of chlorogenic acid from M. purpurea. PMID:25185707

  19. Small-polaron hopping via defect centres: anomalous temperature and voltage dependence of current through fatty-acid monolayers

    We study electron hopping in thin metal-insulator-metal structures which involves two defect centres with a strong electron-phonon coupling. We calculate the dependences of the current, J, on voltage, V, and temperature, T, and show that they are consistent with those observed in molecular monolayers of fatty acids. We analyse in detail an unusual, near-exponential temperature dependence of the current: J(T) ∝ exp (T/T0) T ≥ 50 K in eicosanoic acid (C20) organic monolayers sandwiched between Pt electrodes, where the parameter T0 increases with the bias voltage. We show that at relatively high voltages the two-defect small-polaron hopping results in N-shape current-voltage characteristics which were observed in some organic molecular monolayers

  20. A new approach used to explore associations of current Ambrosia pollen levels with current and past meteorological elements.

    Matyasovszky, István; Makra, László; Csépe, Zoltán; Deák, Áron József; Pál-Molnár, Elemér; Fülöp, Andrea; Tusnády, Gábor

    2015-09-01

    The paper examines the sensitivity of daily airborne Ambrosia (ragweed) pollen levels of a current pollen season not only on daily values of meteorological variables during this season but also on the past meteorological conditions. The results obtained from a 19-year data set including daily ragweed pollen counts and ten daily meteorological variables are evaluated with special focus on the interactions between the phyto-physiological processes and the meteorological elements. Instead of a Pearson correlation measuring the strength of the linear relationship between two random variables, a generalised correlation that measures every kind of relationship between random vectors was used. These latter correlations between arrays of daily values of the ten meteorological elements and the array of daily ragweed pollen concentrations during the current pollen season were calculated. For the current pollen season, the six most important variables are two temperature variables (mean and minimum temperatures), two humidity variables (dew point depression and rainfall) and two variables characterising the mixing of the air (wind speed and the height of the planetary boundary layer). The six most important meteorological variables before the current pollen season contain four temperature variables (mean, maximum, minimum temperatures and soil temperature) and two variables that characterise large-scale weather patterns (sea level pressure and the height of the planetary boundary layer). Key periods of the past meteorological variables before the current pollen season have been identified. The importance of this kind of analysis is that a knowledge of the past meteorological conditions may contribute to a better prediction of the upcoming pollen season. PMID:25376632

  1. A new approach used to explore associations of current Ambrosia pollen levels with current and past meteorological elements

    Matyasovszky, István; Makra, László; Csépe, Zoltán; Deák, Áron József; Pál-Molnár, Elemér; Fülöp, Andrea; Tusnády, Gábor

    2015-09-01

    The paper examines the sensitivity of daily airborne Ambrosia (ragweed) pollen levels of a current pollen season not only on daily values of meteorological variables during this season but also on the past meteorological conditions. The results obtained from a 19-year data set including daily ragweed pollen counts and ten daily meteorological variables are evaluated with special focus on the interactions between the phyto-physiological processes and the meteorological elements. Instead of a Pearson correlation measuring the strength of the linear relationship between two random variables, a generalised correlation that measures every kind of relationship between random vectors was used. These latter correlations between arrays of daily values of the ten meteorological elements and the array of daily ragweed pollen concentrations during the current pollen season were calculated. For the current pollen season, the six most important variables are two temperature variables (mean and minimum temperatures), two humidity variables (dew point depression and rainfall) and two variables characterising the mixing of the air (wind speed and the height of the planetary boundary layer). The six most important meteorological variables before the current pollen season contain four temperature variables (mean, maximum, minimum temperatures and soil temperature) and two variables that characterise large-scale weather patterns (sea level pressure and the height of the planetary boundary layer). Key periods of the past meteorological variables before the current pollen season have been identified. The importance of this kind of analysis is that a knowledge of the past meteorological conditions may contribute to a better prediction of the upcoming pollen season.

  2. Project 2: testing the current critical load maps of acidity for coniferous and deciduous forests.

    Hornung, M.; Creamer, R.; Reynolds, B; Bell, S.; Langan, S.; Kennedy, F; Bradley, I.

    1999-01-01

    Objective: to examine the relationship between mapped exceedance of critical loads of acidity for woodlands, the Ca:A1 ratio of soil solution and forest status as measured by canopy condition and foliar chemistry

  3. Evaluation of different approaches for modeling effects of acid rain on soils in China

    Acid deposition is an environmental problem of increasing concern in China. Acidic soils are common in the southern part of the country and soil acidification caused by acid deposition is expected to occur. Here we test and apply two different approaches for modeling effects of acid deposition and compare results with observed data from sites throughout southern China. The dynamic model MAGIC indicates that, during the last few decades, soil acidification rates have increased considerably due to acid deposition. This acidification will continue if sulfur deposition is not reduced, and if reduced more rapidly than base cation deposition. With the Steady State Mass Balance model (SSMB), and assuming that a molar ratio of Ca2+/Al3+<1 in soil water is harmful to vegetation, we estimate a slight probability for exceedance of the critical load for present deposition rates. Results from both modeling approaches show a strong dependence with deposition of base cations as well as sulfur. Hence, according to the models, changes in emission control of alkaline particulate matter prior to sulfur dioxide will be detrimental to the environment. Model calculations are, however, uncertain, particularly because available data on base cation deposition fluxes are scarce, and that model formulation of aluminum chemistry does not fully reproduce observations. An effort should be made to improve our present knowledge regarding deposition fluxes. Improvements to the model are suggested. Our work indicates that the critical loads presented in the regional acid deposition assessment model RAINS-Asia are too stringent. We find weaknesses in the SSMB approach, developed for northern European conditions, when applying it to Chinese conditions. We suggest an improved effort to revise the risk parameters for use in critical load estimates in China

  4. Iodine-123-labelled fatty acids for myocardial single-photon emission tomography: current status and future perspectives

    Renewed interest in the clinical use of iodine-123-labelled fatty acids is currently primarily focused on the use of iodine-123-labelled 15-(p-iodophenyl)pentadecanoic acid (IPPA) and ''modified'' fatty acid analogues such as 15-(p-iodophenyl)-3-R,S-methylpentadecanoic acid (BMIPP) which show delayed myocardial clearance, thus permitting single-photon emission tomographic imaging. Interest in the use of BMIPP and similar agents results from the differences which have often been observed in various types of heart disease between regional myocardial uptake patterns of [123I]BMIPP and flow tracer distribution. Although the physiological basis is not completely understood, differences between regional fatty acid and flow tracer distribution may reflect alterations in important parameters of metabolism which can be useful for patient management or therapy planning. These tracers may also represent unique metabolic probes for correlation of energy substrate metabolism with regional myocardial viability. The two agents currently most widely used clinically are 123I-labelled IPPA and BMIPP. While [123I]IPPA is commercially available as a radiopharmaceutical in Europe (Cygne) and Canada (Nordion), multicenter trials are in progress in the United States as a prelude to approval for broad use. [123I]BMIPP was recently introduced as Cardiodine for commercial distribution in Japan (Nihon Medi-Physics, Inc.). [123I]BMIPP is also being used in clinical studies on an institutional approval basis at several institutions in Europe and the United States. In this review, the development of a variety of radioiodinated fatty acids is discussed. The results of clinical trials with [123I]IPPA and [123I]BMIPP are discussed in detail, as are the future prospects for fatty acid imaging. (orig.)

  5. A new approach to detect broken rotor bars in induction machines by current spectrum analysis

    Didier, G.; Ternisien, E.; Caspary, O.; Razik, H.

    2007-02-01

    This paper deals with a new technique to detect broken rotor bars in polyphase induction machines. Like most techniques, we employ the Fourier Transform of the stator current to make detection. But where the other methods use the Fourier Transform modulus, this alternative approach proposes to analyse its phase. As shown by results, the Fourier Transform phase allows to detect one broken rotor bar when the motor operates under a low load but the method robustness decreases for a half-broken rotor bar. So, in order to improve the diagnosis and to permit the detection of incipient broken rotor bar, the analysis is completed with the Hilbert Transform. This transform provides good results and a partially broken rotor bar can be detected when the load torque is equal or greater than 25%. The main advantage of these methods is that the final decision on the rotor cage state is took without the healthy motor reference.

  6. Practical Framework for an Electron Beam Induced Current Technique Based on a Numerical Optimization Approach

    Yamaguchi, Hideshi; Soeda, Takeshi

    2015-03-01

    A practical framework for an electron beam induced current (EBIC) technique has been established for conductive materials based on a numerical optimization approach. Although the conventional EBIC technique is useful for evaluating the distributions of dopants or crystal defects in semiconductor transistors, issues related to the reproducibility and quantitative capability of measurements using this technique persist. For instance, it is difficult to acquire high-quality EBIC images throughout continuous tests due to variation in operator skill or test environment. Recently, due to the evaluation of EBIC equipment performance and the numerical optimization of equipment items, the constant acquisition of high contrast images has become possible, improving the reproducibility as well as yield regardless of operator skill or test environment. The technique proposed herein is even more sensitive and quantitative than scanning probe microscopy, an imaging technique that can possibly damage the sample. The new technique is expected to benefit the electrical evaluation of fragile or soft materials along with LSI materials.

  7. Current approaches to the diagnosis and treatment of idiopathic pulmonary fibrosis in Europe: the AIR survey

    Vincent Cottin

    2014-06-01

    Full Text Available This review presents the results of the 2013 Advancing IPF Research (AIR survey, which assessed current approaches to the diagnosis and treatment of idiopathic pulmonary fibrosis (IPF by experienced physicians. A total of 149 physicians, predominantly from European countries, replied to the 28-question survey. The results of the AIR survey were compared with a similar survey of 509 French pulmonologists conducted by the French National Reference Centre and the Network of Regional Competence Centres for Rare Lung Diseases. A number of positive findings emerged from the AIR survey, including the high level of multidisciplinary team involvement in both diagnosis and management. This survey, when taken together with the French survey, suggests that there is still a need to improve earlier diagnosis of IPF.

  8. Prevention of Overweight and Obesity: How Effective is the Current Public Health Approach

    Jean Woo

    2010-02-01

    Full Text Available Obesity is a public health problem that has become epidemic worldwide. Substantial literature has emerged to show that overweight and obesity are major causes of co-morbidities, including type II diabetes, cardiovascular diseases, various cancers and other health problems, which can lead to further morbidity and mortality. The related health care costs are also substantial. Therefore, a public health approach to develop population-based strategies for the prevention of excess weight gain is of great importance. However, public health intervention programs have had limited success in tackling the rising prevalence of obesity. This paper reviews the definition of overweight and obesity and the variations with age and ethnicity; health consequences and factors contributing to the development of obesity; and critically reviews the effectiveness of current public health strategies for risk factor reduction and obesity prevention.

  9. Risk stratification for sudden cardiac death: current approaches and predictive value.

    Lopera, Gustavo; Curtis, Anne B

    2009-01-01

    Sudden cardiac death (SCD) is a serious public health problem; the annual incidence of out-of-hospital cardiac arrest in North America is approximately 166,200. Identifying patients at risk is a difficult proposition. At the present time, left ventricular ejection fraction (LVEF) remains the single most important marker for risk stratification. According to current guidelines, most patients with LVEF strategies fail to identify patients at risk of SCD in larger population groups encompassing a greater number of potential SCD victims. However, the best approach to identifying patients and the value of various risk stratification tools is not entirely clear. The goal of this review is to discuss the problem of SCD and the value of the different risk stratification markers and their potential clinical use either alone or in combination with other risk stratification markers. PMID:20066150

  10. Current Approach in Surface Plasmons for Thin Film and Wire Array Solar Cell Applications

    Keya Zhou

    2015-07-01

    Full Text Available Surface plasmons, which exist along the interface of a metal and a dielectric, have been proposed as an efficient alternative method for light trapping in solar cells during the past ten years. With unique properties such as superior light scattering, optical trapping, guide mode coupling, near field concentration, and hot-electron generation, metallic nanoparticles or nanostructures can be tailored to a certain geometric design to enhance solar cell conversion efficiency and to reduce the material costs. In this article, we review current approaches on different kinds of solar cells, such as crystalline silicon (c-Si and amorphous silicon (a-Si thin film solar cells, organic solar cells, nanowire array solar cells, and single nanowire solar cells.

  11. Approaches to improve the oral bioavailability and effects of novel anticancer drugs berberine and betulinic acid.

    Chandraiah Godugu

    Full Text Available The poor bioavailability of Berberine (BBR and Betulinic acid (BA limits the development of these promising anticancer agents for clinical use. In the current study, BBR and BA in spray dried (SD mucoadhesive microparticle formulations were prepared.A patented dual channel spray gun technology established in our laboratory was used for both formulations. Gastrointestinal (GI permeability studies were carried out using Caco-2 cell monolayer grown in in-vitro system. The oral bioavailability and pharmacokinetic profile of SD formulations were studied in Sprague Dawley rats. A549 orthotopic and H1650 metastatic NSCLC models were utilized for the anticancer evaluations.Pharmacokinetic studies demonstrated that BBR and BA SD formulations resulted in 3.46 and 3.90 fold respectively, significant increase in plasma Cmax concentrations. AUC levels were increased by 6.98 and 7.41 fold in BBR and BA SD formulations, respectively. Compared to untreated controls groups, 49.8 & 53.4% decrease in the tumor volumes was observed in SD formulation groups of BBR and BA, respectively. Molecular studies done on excised tumor (A549 tissue suggested that BBR in SD form resulted in a significant decrease in the survivin, Bcl-2, cyclin D1, MMP-9, HIF-1α, VEGF and CD31 expressions. Cleaved caspase 3, p53 and TUNEL expressions were increased in SD formulations. The RT-PCR analysis on H1650 tumor tissue suggested that p38, Phospho-JNK, Bax, BAD, cleaved caspase 3&8 mRNA expressions were significantly increased in BA SD formulations. Chronic administration of BBR and BA SD formulations did not show any toxicity.Due to significant increase in oral bioavailability and superior anticancer effects, our results suggest that spray drying is a superior alternative formulation approach for oral delivery of BBR and BA.

  12. Exchange processes at geosphere-biosphere interface. Current SKB approach and example of coupled hydrological-ecological approach

    Woerman, Anders [Swedish Univ. of Agricultural Sciences, Uppsala (Sweden). Dept. of Biometry and Technology

    2003-09-01

    The design of the repository for final disposal of spent nuclear fuel proposed by SKB is based on a multi-barrier system, in which the geosphere and biosphere are the utmost barrier surrounding the engineer barriers. This report briefly reviews the current approach taken by SKB to account for hydrological and ecological processes at the geosphere-biosphere interface (GBI) and their future plans in this area. A simple analysis was performed to shift the focus of performance assessment involving geosphere-biosphere interface modelling from the very simplistic assumption that the quaternary sediments are bypassed to one in which a more detailed model for sub-surface flows is included. This study indicated that, for many assumed ecosystem descriptions, the presence of the GBI leads to lower maximum doses to individual humans compared to a case when the GBI is neglected. This effect is due to the additional 'barrier' offered by the GBI. The main exposure pathways were assumed to occur through the food web. However, particularly the leakage on land through the stream-network and lakes can lead to higher doses due to ecosystem interaction with arable land. A scenario that gives particularly long duration of doses occurs due to land rise and with the transformation of the former bay and lake bed sediments into agricultural land. This effect is due to the significant retention or accumulation in aquatic sediment, which causes high activities to build up with time. Particularly, in combination with changing conditions in climate, humans life-style or geographic conditions (land rise, deforestation,etc.) doses to individual humans can be large.

  13. Exchange processes at geosphere-biosphere interface. Current SKB approach and example of coupled hydrological-ecological approach

    The design of the repository for final disposal of spent nuclear fuel proposed by SKB is based on a multi-barrier system, in which the geosphere and biosphere are the utmost barrier surrounding the engineer barriers. This report briefly reviews the current approach taken by SKB to account for hydrological and ecological processes at the geosphere-biosphere interface (GBI) and their future plans in this area. A simple analysis was performed to shift the focus of performance assessment involving geosphere-biosphere interface modelling from the very simplistic assumption that the quaternary sediments are bypassed to one in which a more detailed model for sub-surface flows is included. This study indicated that, for many assumed ecosystem descriptions, the presence of the GBI leads to lower maximum doses to individual humans compared to a case when the GBI is neglected. This effect is due to the additional 'barrier' offered by the GBI. The main exposure pathways were assumed to occur through the food web. However, particularly the leakage on land through the stream-network and lakes can lead to higher doses due to ecosystem interaction with arable land. A scenario that gives particularly long duration of doses occurs due to land rise and with the transformation of the former bay and lake bed sediments into agricultural land. This effect is due to the significant retention or accumulation in aquatic sediment, which causes high activities to build up with time. Particularly, in combination with changing conditions in climate, humans life-style or geographic conditions (land rise, deforestation,etc.) doses to individual humans can be large

  14. Current Advance and Future Prospects of Tissue Engineering Approach to Dentin/Pulp Regenerative Therapy.

    Gong, Ting; Heng, Boon Chin; Lo, Edward Chin Man; Zhang, Chengfei

    2016-01-01

    Recent advances in biomaterial science and tissue engineering technology have greatly spurred the development of regenerative endodontics. This has led to a paradigm shift in endodontic treatment from simply filling the root canal systems with biologically inert materials to restoring the infected dental pulp with functional replacement tissues. Currently, cell transplantation has gained increasing attention as a scientifically valid method for dentin-pulp complex regeneration. This multidisciplinary approach which involves the interplay of three key elements of tissue engineering-stem cells, scaffolds, and signaling molecules-has produced an impressive number of favorable outcomes in preclinical animal studies. Nevertheless, many practical hurdles need to be overcome prior to its application in clinical settings. Apart from the potential health risks of immunological rejection and pathogenic transmission, the lack of a well-established banking system for the isolation and storage of dental-derived stem cells is the most pressing issue that awaits resolution and the properties of supportive scaffold materials vary across different studies and remain inconsistent. This review critically examines the classic triad of tissue engineering utilized in current regenerative endodontics and summarizes the possible techniques developed for dentin/pulp regeneration. PMID:27069484

  15. Ocean Current Energy Conversion System in Wallacea Region Using Variable Speed Control Approach

    Aditya Sukma Nugraha

    2012-03-01

    Full Text Available Ocean Current Energy Conversion System (OCECS is a promising green energy resource in this globe. The Thermohaline circulation data indicates that the Wallacea region has the potential of ocean current energy resources. This paper is aimed to propose research and development of OCECSs to be implemented in the Wallacea region. Firstly, four types of green energy conversion systems extracted from ocean are reviewed. Their advantages and disadvantages are discussed. Secondly, the potential of OCECS in the Wallacea region is described. Third, many types of turbines used for OCECS are reviewed and the turbine type for OCECS is selected to be implemented in the Wallacea region. Fourth, control strategy is proposed.From the work reported in this paper it is concluded that it is appropriate to implement OCECSs using axial flow water turbines in the Wallacea region, and that to maximize energy conversion variable speed control approach is selected together with control of mechanism to move the turbine vertically as well as to rotate the turbine in yaw direction. 

  16. Marketing of library and information services in global era: A current approach

    Sanjay Kumar Karn

    2008-06-01

    Full Text Available This paper deals with the marketing of library and information services in the global era. It discusses about the marketing concept of today's library and information centers covering various topics such as management of libraries and commitment to customer's satisfaction. It also defines the marketing and its current approach to library and information services at the global level. It also describes customer/user's topic such as customers' priorities, customers' expectations, individuality responsiveness, relationships, quality of services, professional skills and competencies and value added services. The 5 Ps of marketing mix, i.e. product, pricing, place, promotion and person (staff have been discussed. The marketing should aim at effective library and information services. The "service trinity", i.e. users (customers, the staff (service provider and information resources and system should be taken care of from the view of these services. In the modern age, the library and information services (LIS are customer (user oriented. Therefore, users' priorities, expectations and needs should be taken into account. The services should be value added according to the current requirement of the users. It is concluded that the modern libraries are information markets and the library users are consumers of information. The ultimate objective of the marketing of library and information services should be the dissemination of the right information to the right customer (user at the right time.

  17. Structural Investigation for Optimization of Anthranilic Acid Derivatives as Partial FXR Agonists by in Silico Approaches

    Meimei Chen; Xuemei Yang; Xinmei Lai; Jie Kang; Huijuan Gan; Yuxing Gao

    2016-01-01

    In this paper, a three level in silico approach was applied to investigate some important structural and physicochemical aspects of a series of anthranilic acid derivatives (AAD) newly identified as potent partial farnesoid X receptor (FXR) agonists. Initially, both two and three-dimensional quantitative structure activity relationship (2D- and 3D-QSAR) studies were performed based on such AAD by a stepwise technology combined with multiple linear regression and comparative molecular field an...

  18. Combined approach to counteract experimental cancer cachexia: eicosapentaenoic acid and training exercise

    Penna, Fabio; Busquets, Silvia; Pin, Fabrizio; Toledo, Miriam; Francesco M Baccino; López-Soriano, Francisco J.; Costelli, Paola; Argilés, Josep M.

    2011-01-01

    Background Cancer cachexia is a syndrome characterized by loss of skeletal muscle protein, depletion of lipid stores, anorexia, weakness, and perturbations of the hormonal homeostasis. Despite several therapeutic approaches described in the past, effective interventions countering cancer cachexia are still lacking. Methods The present work was aimed to verify the ability of eicosapentaenoic acid (EPA) to prevent the muscle depletion in Lewis lung carcinoma-bearing mice and to test the ability...

  19. Current Techniques for the Cultivation of Ganoderma lucidum for the Production of Biomass, Ganoderic Acid and Polysaccharides

    Wagner, Ricardo; Mitchell, David Alexander; Lanzi Sassaki, Guilherme; Lopes de Almeida Amazonas, Maria Angela; Berovič, Marin

    2003-01-01

    Ganoderma lucidum is a medicinal mushroom that has been used in the Orient for more than 2000 years. Due to the long time required for basidiocarp formation, attention has recently been given to the use of submerged fermentation for the production of mycelial biomass and its bioactive components, such as polysaccharides and ganoderic acids. We review the current state of knowledge about the cultivation of G. lucidum by modern fermentation techniques, focussing on the effects of fermentation c...

  20. Ascorbic acid, cognitive function, and Alzheimer’s disease: a current review and future direction

    Bowman, Gene L.

    2012-01-01

    This narrative review appraises the human and animal studies implicating ascorbic acid (AA) in normal cognitive function and Alzheimer’s disease. A research framework for how nutrition affects brain aging is proposed with emphasis on AA intake, status, metabolism, and transport into brain tissue. A final synopsis highlights areas for future research regarding AA nourishment and healthy brain aging.

  1. History and current status of valve-regulated lead/acid batteries in Japan

    Nakashima, Hiroto; Fuchida, Kyo

    The valve-regulated design of the sealed lead/acid battery (VRB), developed in the first half of the 1960s in Japan for use in portable television sets, has achieved successful market growth. This paper reviews the history of development of VRBs during the past thirty years, present production models, production quality, major applications, and technical problems.

  2. Suberoylanilide Hydroxamic Acid (Vorinostat) Up-regulates Progranulin Transcription: RATIONAL THERAPEUTIC APPROACH TO FRONTOTEMPORAL DEMENTIA*

    Cenik, Basar; Sephton, Chantelle F.; Dewey, Colleen M.; Xian, Xunde; Wei, Shuguang; Yu, Kimberley; Niu, Wenze; Coppola, Giovanni; Coughlin, Sarah E.; Lee, Suzee E.; Dries, Daniel R.; Almeida, Sandra; Geschwind, Daniel H.; Gao, Fen-Biao; Miller, Bruce L.

    2011-01-01

    Progranulin (GRN) haploinsufficiency is a frequent cause of familial frontotemporal dementia, a currently untreatable progressive neurodegenerative disease. By chemical library screening, we identified suberoylanilide hydroxamic acid (SAHA), a Food and Drug Administration-approved histone deacetylase inhibitor, as an enhancer of GRN expression. SAHA dose-dependently increased GRN mRNA and protein levels in cultured cells and restored near-normal GRN expression in haploinsufficient cells from ...

  3. Current and future perspectives on the development, evaluation and application of in silico approaches for predicting toxicity

    Safety-related problems continue to be one of the major reasons of attrition in drug development. Non-testing approaches to predict toxicity could form part of the solution. This review provides a perspective of current status of non-testing approaches available for the predictio...

  4. Current standards and new innovative approaches for treatment of pancreatic cancer.

    Conroy, Thierry; Bachet, Jean-Baptiste; Ayav, Ahmet; Huguet, Florence; Lambert, Aurélien; Caramella, Caroline; Maréchal, Raphaël; Van Laethem, Jean-Luc; Ducreux, Michel

    2016-04-01

    Pancreatic adenocarcinoma remains a devastating disease with a 5-year survival rate not exceeding 6%. Treatment of this disease remains a major challenge. This article reviews the state-of-the-art in the management of this disease and the new innovative approaches that may help to accelerate progress in treating its victims. After careful pre-therapeutic evaluation, only 15-20% of patients diagnosed with a pancreatic cancer (PC) are eligible for upfront radical surgery. After R0 or R1 resection in such patients, evidence suggests a significantly positive impact on survival of adjuvant chemotherapy comprising 6 months of gemcitabine or fluorouracil/folinic acid. Delayed adjuvant chemoradiation is considered as an option in cases of positive margins. Borderline resectable pancreatic cancer (BRPC) is defined as a tumour involving the mesenteric vasculature to a limited extend. Resection of these tumours is technically feasible, yet runs the high risk of a R1 resection. Neoadjuvant treatment probably offers the best chance of achieving successful R0 resection and long-term survival, but the best treatment options should be determined in prospective randomised studies. Gemcitabine has for 15 years been the only validated therapy for advanced PC. Following decades of negative phase III studies, increasing evidence now suggests that further significant improvements to overall survival can be achieved via either Folfirinox or gemcitabine + nab-paclitaxel regimens. Progress in systemic therapy may improve the chances of resection in borderline resectable pancreatic cancer (BRPC) or locally advanced PC. This requires first enhancing knowledge of the genetic events driving carcinogenesis, which may then be translated into clinical studies. PMID:26851397

  5. Sexuality after stroke: an exploration of current professional approaches, barriers to providing support and future directions.

    Richards, Alexandra; Dean, Rachel; Burgess, Gerald H; Caird, Helen

    2016-07-01

    Purpose Sexual difficulties post-stroke are common, yet frequently neglected within rehabilitation. This study aimed to explore the process by which healthcare professionals approach and work with the topic of sexuality within stroke rehabilitation. Method Ten participants were recruited from 5 community and inpatient multi-disciplinary stroke rehabilitation teams. Semi-structured interviews were carried out and data were analysed using grounded theory methodology. Results The authors developed a theoretical model of how professionals engage with sexual concerns. Professionals' own personal level of comfort with the topic of sexuality interacted with a series of barriers to limit opportunities for engagement. These barriers included factors relating to the context and workplace environment of stroke rehabilitation, professionals' perceptions that they did not have adequate skills in this area and unhelpful attitudes towards stroke survivors and sexuality. Although the majority of participants rarely engaged with sexual issues, they adopted both direct and indirect strategies for engaging with their service users' sexual concerns. Concerns were usually addressed through the provision of information and supportive conversations. Conclusions The findings suggest that sexuality is not a legitimised topic within stroke rehabilitation, and current work practises limit professionals' abilities to address service-users' concerns. Implications for developing effective training and staff support are discussed. Implications for rehabilitation Professionals working within stroke rehabilitation rarely directly bring up sexuality with patients, but an indirect method of approaching the topic is more common. Addressing sexual concerns often does not require expertise. Training should show professionals how to use transferable knowledge to address sexual issues and also enhance communication skills. Sexuality should be incorporated within local stroke policy and procedures, to

  6. Current approaches to treatments for schizophrenia spectrum disorders, part I: an overview and medical treatments.

    Chien, Wai Tong; Yip, Annie Lk

    2013-01-01

    During the last three decades, an increasing understanding of the etiology, psychopathology, and clinical manifestations of schizophrenia spectrum disorders, in addition to the introduction of second-generation antipsychotics, has optimized the potential for recovery from the illness. Continued development of various models of psychosocial intervention promotes the goal of schizophrenia treatment from one of symptom control and social adaptation to an optimal restoration of functioning and/or recovery. However, it is still questionable whether these new treatment approaches can address the patients' needs for treatment and services and contribute to better patient outcomes. This article provides an overview of different treatment approaches currently used in schizophrenia spectrum disorders to address complex health problems and a wide range of abnormalities and impairments resulting from the illness. There are different treatment strategies and targets for patients at different stages of the illness, ranging from prophylactic antipsychotics and cognitive-behavioral therapy in the premorbid stage to various psychosocial interventions in addition to antipsychotics for relapse prevention and rehabilitation in the later stages of the illness. The use of antipsychotics alone as the main treatment modality may be limited not only in being unable to tackle the frequently occurring negative symptoms and cognitive impairments but also in producing a wide variety of adverse effects to the body or organ functioning. Because of varied pharmacokinetics and treatment responsiveness across agents, the medication regimen should be determined on an individual basis to ensure an optimal effect in its long-term use. This review also highlights that the recent practice guidelines and standards have recommended that a combination of treatment modalities be adopted to meet the complex health needs of people with schizophrenia spectrum disorders. In view of the heterogeneity of the risk

  7. Human-carnivore conflict in China: a review of current approaches with recommendations for improved management.

    Pettigrew, Melissa; Xie, Yan; Kang, Aili; Rao, Madhu; Goodrich, John; Liu, Tong; Berger, Joshua

    2012-06-01

    Human-wildlife conflict (HWC) is a conservation concern that increasingly threatens the continued existence of some of the world's most endangered species. With an increase in human population, urban sprawl and subsequent encroachment on wild land, human and wildlife interaction has become inevitable. In the majority of cases, this interaction results in a negative outcome for humans, wildlife or both. In China, these key elements, along with a decrease in wild prey species, have resulted in the expansion of HWC encounters, and the need for alleviating this conflict has become a conservation priority. Loss of human life, livestock and/or crops is most often the catalysts that fuel HWC. Techniques to alleviate conflict around the world have included preventative measures and mitigation techniques, such as financial compensation and other incentive programs. Both types of measures have had variable success. We review the current status of human-carnivore conflict management in China, and, drawing lessons from around the globe, we make recommendations for improving conservation management in China. For example, an increase in law enforcement in nature reserves is vital to reducing human disturbance in prime carnivore habitat, thereby reducing conflict encounters. Also, modifications to current wildlife compensation programs, so that they are linked with preventative measures, will ensure that moral hazards are avoided. Furthermore, investigating the potential for a community self-financed insurance scheme to fund compensation and increasing efforts to restore wild prey populations will improve the outcome for wildlife conservation. Ultimately, HWC management in China will greatly benefit from an integrative approach. PMID:22691204

  8. A Vectorial Approach for Generation of Optimal Current References for Multiphase Permanent-Magnet Synchronous Machines in Real Time

    Kestelyn, Xavier; SEMAIL, Eric

    2011-01-01

    This paper deals with the generation of optimal current references for multiphase permanent-magnet (PM) synchronous machines in normal or fault mode (open-circuited phases). Current references are computed in order to keep a constant torque while minimizing instantaneous joule losses. In comparison with commonly used scalar methods, a vectorial approach makes it possible to reduce the number of computations in order to generate optimal current references in real time. In addition to this, sin...

  9. Current issues in determining dietary protein and amino-acid requirements

    Pencharz, P; Jahoor, F; Kurpad, A;

    2014-01-01

    Pregnancy and the first two years of life are periods of rapid growth and yet the knowledge of requirements for protein and dietary indispensable amino acids is very limited. The development of carbon oxidation methods opens the way to studies that should fill these important gaps in knowledge.Eu.......European Journal of Clinical Nutrition advance online publication, 15 January 2014; doi:10.1038/ejcn.2013.297....

  10. Approach to integrate current safeguards measures with additional protocol requirements at national level

    Peru adhered to the Additional Protocol in March 2000 which was also approved by the Congress in May 2001. After approval by law the obligations derived from this Additional Protocol will be in force after 180 days. After the signing of the Protocol an approach was designed to help better fulfill these requirements in an integrated way with the previous measures. As first stage, a review of the current state of safeguards was undertaken. Under the current agreement (an INFCIRC/153 type agreement) the reporting is less complicated and inexpensive to be carried out because these reports include only the declared nuclear material and the features of declared facilities where the nuclear material is used. No other related facility or material or activity needs to be declared. In Peru there are only two MBAs where low enriched uranium (LEU) is used and the record system includes general ledgers, inventory records and operational books. The results of national inspections and copies of reports and communications sent to the IAEA are also kept in this system. Under the agreement and subsidiary arrangements material balance reports (MBR), physical inventory listings (PIL) and inventory change reports (ICR) are prepared and submitted to the IAEA at scheduled periods. The MBR and PIL reports are sent after yearly regular inspections carried out by the IAEA. The ICR is sent just every time when an import or export of nuclear material is made. The time devoted to carry out all of these activities is not so extensive for both the State System for Accountability and Control (SSAC) and the users because of the limited nuclear activities in the country. Because of the characteristics and limited quantities of nuclear material the efforts for inspection and reporting activities are few. Another subject under review was the procedure for controlling the imports of nuclear material. Under the current agreement this subject was not a problem, as all of the radioactive and nuclear

  11. Novel colloidal carriers for psoriasis: current issues, mechanistic insight and novel delivery approaches.

    Pradhan, Madhulika; Singh, Deependra; Singh, Manju Rawat

    2013-09-28

    Psoriasis is an autoimmune disorder of the skin with relapsing episodes of inflammation and hyperkeratosis. Numerous approaches have been explored to treat this dreadful disease using different antipsoriatic drugs with different modes of action and routes of administration. But, till date there is no cure for psoriasis due to lack of an ideal carrier for safe and effective delivery of antipsoriatic drugs. Constant progression in the development of newer formulations utilizing colloidal drug delivery systems has led to effective treatment of psoriasis. Colloidal carriers include vesicular and particulate systems like liposome, transferosome, niosomes, ethosomes, solid lipid nanoparticles, microspheres, micelles, dendrimers etc. have gained unique position as drug cargoes. Present review is an attempt to contemplate on psoriasis in terms of pathogenesis, role of cytokines, major hindrances in psoriasis treatment, currently available treatment options pertaining to mode of action, pharmacokinetics, marketed products, side effects of individual antipsoriatic drugs and recent developments in the delivery of various antipsoriatic drugs through novel colloidal drug carriers. PMID:23770117

  12. Modeling left and right atrial contributions to the ECG: A dipole-current source approach.

    Jacquemet, Vincent

    2015-10-01

    This paper presents the mathematical formulation, the numerical validation and several illustrations of a forward-modeling approach based on dipole-current sources to compute the contribution of a part of the heart to the electrocardiogram (ECG). Clinically relevant applications include identifying in the ECG the contributions from the right and the left atrium. In a Courtemanche-based monodomain computer model of the atria and torso, 1000 dipoles distributed throughout the atrial mid-myocardium are found to be sufficient to reproduce body surface potential maps with a relative error ECG contribution of any anatomical part of the atria by applying the principle of superposition to the dipole sources. In the presence of a right-left activation delay (sinus rhythm), pulmonary vein isolation (sinus rhythm) or left-right differences in refractory period (atrial fibrillation), the decomposition of the ECG is shown to help interpret ECG morphology in relation to the atrial substrate. These tools provide a theoretical basis for a deeper understanding of the genesis of the P wave or fibrillatory waves in normal and pathological cases. PMID:26149374

  13. Quality management in European screening laboratories in blood establishments: A view of current approaches and trends.

    Pereira, Paulo; Westgard, James O; Encarnação, Pedro; Seghatchian, Jerard; de Sousa, Gracinda

    2015-04-01

    The screening laboratory has a critical role in the post-transfusion safety. The success of its targets and efficiency depends on the management system used. Even though the European Union directive 2002/98/EC requires a quality management system in blood establishments, its requirements for screening laboratories are generic. Complementary approaches are needed to implement a quality management system focused on screening laboratories. This article briefly discusses the current good manufacturing practices and good laboratory practices, as well as the trends in quality management system standards. ISO 9001 is widely accepted in some European Union blood establishments as the quality management standard, however this is not synonymous of its successful application. The ISO "risk-based thinking" is interrelated with the quality risk-management process of the EuBIS "Standards and criteria for the inspection of blood establishments". ISO 15189 should be the next step on the quality assurance of a screening laboratory, since it is focused on medical laboratory. To standardize the quality management systems in blood establishments' screening laboratories, new national and European claims focused on technical requirements following ISO 15189 is needed. PMID:25765135

  14. Molecular mechanisms of medullary thyroid carcinoma: current approaches in diagnosis and treatment.

    Boikos, S A; Stratakis, C A

    2008-01-01

    Medullary thyroid carcinoma is the most common cause of death among patients with multiple endocrine neoplasia (MEN) 2. Dominant-activating mutations in the RET proto-oncogene have been shown to have a central role in the development of MEN 2 and sporadic medullary thyroid cancer (MTC): about half of sporadic MTCs are caused by somatic genetic changes of the RET oncogene. Inactivating mutations of the same gene lead to Hirschprung disease and other developmental defects. Thus, RET genetic changes lead to phenotypes that largely depend on their location in the gene and the function and timing of developmental expression of the RET protein. The reproducibility of the phenotype caused by each RET genotype led to MEN 2/MTC being among the first conditions in Medicine where a drastic measure is applied to prevent cancer, following genetic testing: thyroidectomy is currently routinely done in young children that are carriers of MTC-predisposing RET mutations. RET inhibitors have been also developed recently and are used in various types of thyroid and other cancers. This report reviews the RET involvement in the etiology of MEN 2 and MTC and updates the therapeutic approach in preclinical and clinical studies. PMID:17952863

  15. Silencing gamma-aminobutyric acid A receptor alpha 1 subunit expression and outward potassium current in developing cortical neurons

    Tao Bo; Jiang Li; Jian Li; Xingfang Li; Kaihui Xing

    2011-01-01

    We used RNA interference (RNAi) to disrupt synthesis of the cortical neuronal γ-aminobutyric acid A receptor (GABAAR) α1 in rats during development, and measured outward K+ currents during neuronal electrical activity using whole-cell patch-clamp techniques. Three pairs of small interfering RNA (siRNA) for GABAAR α1 subunit were designed using OligoEngine RNAi software. This siRNA was found to effectively inhibited GABAAR α1 mRNA expression in cortical neuronal culture in vitro, but did not significantly affect neuronal survival. Outward K+ currents were decreased, indicating that GABAAR α1 subunits in developing neurons participate in neuronal function by regulating outward K+ current.

  16. Isotope separation of carbon-13 by counter-current column with exchange reaction between carbon dioxide and carbamic acid

    The isotope separation performance of carbon-13 with exchange reaction between CO2 and carbamic acid was studied and some factors for the counter-current column were studied for improving the overall performance. The working fluid for the experiments was a solution of DNBA, (C4H9)2NH, and n-octane mixture. The rate-controlling step of 13C transfer at temperatures higher than 10 deg C was the exchange reaction between carbamic acid and CO2 dissolved by physical absorption. The capacity coefficient of 13C transfer between gas and liquid in the counter-current column was successfully related to the product of three factors: the concentration of carbamic acid, the concentration of CO2 dissolved by physical absorption and the liquid holdup of the column. The liquid holdup was also an important factor. As the holdup increased, the isotope exchange rate and the overall separation factor of the column increased. However, the transient time to equilibrium was much longer. (author)

  17. A new approach to study cadmium complexes with oxalic acid in soil solution

    This study presents a new analytical approach for the determination of heavy metals complexed to low-molecular-weight-organic acids in soil solutions, which combines the sensitivity of differential pulse anodic stripping voltammetry (DPASV) with the molecular insight gained by electrospray ionization mass spectrometry (ESI-MS). The combination of these analytical methods allows the investigation of such complexes in complex matrixes. On the voltammograms of the soil solutions, in addition to the expected complexes of oxalic acid with cadmium and lead, respectively, also peaks belonging to mixed complexes of cadmium, lead, and oxalic acid (OAH2) were observed. In order to verify the possible formation of complexes with OAH2, aqueous solutions of OAH2 with traces of Cd(II) were investigated as model systems. Signals corresponding to several distinct molecular complexes between cadmium and oxalic acid were detected in the model solutions using negative-ion ESI-MS, which follow the general formula [Cdn(X,Y)(2n+1)]-, where n is the number of cadmium atoms, X = Cl-, and Y = OAH-. Some of these complexes were also identified in the ESI mass spectra taken from the soil solutions.

  18. Amino Acid Prodrugs: An Approach to Improve the Absorption of HIV-1 Protease Inhibitor, Lopinavir

    Mitesh Patel

    2014-04-01

    Full Text Available Poor systemic concentrations of lopinavir (LPV following oral administration occur due to high cellular efflux by P-glycoprotein (P-gp and multidrug resistance-associated proteins (MRPs and extensive metabolism by CYP3A4 enzymes. In this study, amino acid prodrugs of LPV were designed and investigated for their potential to circumvent efflux processes and first pass effects. Three amino acid prodrugs were synthesized by conjugating isoleucine, tryptophan and methionine to LPV. Prodrug formation was confirmed by the LCMS/MS and NMR technique. Interaction of LPV prodrugs with efflux proteins were carried out in P-gp (MDCK-MDR1 and MRP2 (MDCK-MRP2 transfected cells. Aqueous solubility studies demonstrated that prodrugs generate higher solubility relative to LPV. Prodrugs displayed higher stability under acidic conditions and degraded significantly with rise in pH. Uptake and transport data suggested that prodrugs carry significantly lower affinity towards P-gp and MRP2 relative to LPV. Moreover, prodrugs exhibited higher liver microsomal stability relative to LPV. Hence, amino acid prodrug modification might be a viable approach for enhancing LPV absorption across intestinal epithelial and brain endothelial cells which expresses high levels of P-gp and MRP2.

  19. Current approaches to treatments for schizophrenia spectrum disorders, part I: an overview and medical treatments

    Chien WT

    2013-09-01

    Full Text Available Wai Tong Chien, Annie LK Yip School of Nursing, Faculty of Health and Social Sciences, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong Abstract: During the last three decades, an increasing understanding of the etiology, psychopathology, and clinical manifestations of schizophrenia spectrum disorders, in addition to the introduction of second-generation antipsychotics, has optimized the potential for recovery from the illness. Continued development of various models of psychosocial intervention promotes the goal of schizophrenia treatment from one of symptom control and social adaptation to an optimal restoration of functioning and/or recovery. However, it is still questionable whether these new treatment approaches can address the patients' needs for treatment and services and contribute to better patient outcomes. This article provides an overview of different treatment approaches currently used in schizophrenia spectrum disorders to address complex health problems and a wide range of abnormalities and impairments resulting from the illness. There are different treatment strategies and targets for patients at different stages of the illness, ranging from prophylactic antipsychotics and cognitive–behavioral therapy in the premorbid stage to various psychosocial interventions in addition to antipsychotics for relapse prevention and rehabilitation in the later stages of the illness. The use of antipsychotics alone as the main treatment modality may be limited not only in being unable to tackle the frequently occurring negative symptoms and cognitive impairments but also in producing a wide variety of adverse effects to the body or organ functioning. Because of varied pharmacokinetics and treatment responsiveness across agents, the medication regimen should be determined on an individual basis to ensure an optimal effect in its long-term use. This review also highlights that the recent practice guidelines and standards have

  20. Policies for a greener agriculture: the agro-ecological approach of current programs in Brazil.

    Abreu, Lucimar Santiago de; Almeida, Gustavo Ferreira

    2011-01-01

    Based a multiple-cases-study approach, our main objective is to discuss to what extent the new political approach of 2003 has been able so far to obtain and increase concrete progress in rural areas in Brazil.

  1. Pathophysiology of asthma: what has our current understanding taught us about new therapeutic approaches?

    Holgate, Stephen T

    2011-09-01

    Current asthma therapy is based on the use of adrenergic bronchodilator and anti-inflammatory drugs the specificity, efficacy, duration of action, and safety of which have been derived through classical pharmacology and medicinal chemistry. That asthma is a T(H)2-type inflammatory disorder frequently associated with atopy and allergic comorbidities has led to a concentrated effort to find treatments that act selectively on this pathway. A systematic literature review was undertaken, as well as a review of the Web site Clinicaltrials.gov for ongoing trials. Targets have included T cells themselves and their associated cytokines, chemokines, and receptors mostly targeted with biological agents. With the exception of anti-human IgE, none of these have met the expectations predicted from animal models and human in vitro tests. For most of these new therapies, only a very small subpopulation appears to respond. A case is made for a different approach to drug discovery based on acquiring a greater understanding of asthma stratification, the relevant pathways involved, and the development of appropriate diagnostic tests enabling the targeting of selective treatments to those asthmatic phenotypes most likely to respond. The recognition that asthma is more than allergy mandates improved predictive animal models and an appreciation that many of the environmental insults that initiate, consolidate, and exacerbate asthma operate through an epithelium functioning in a disorderly fashion. An integrated model that places the epithelium at the forefront of asthma pathogenesis suggests that greater emphasis should be placed on therapeutics that increase the airways' resistance against the inhaled environment rather than focusing only on suppression of inflammation. PMID:21807404

  2. Current dependence of spin torque switching rate based on Fokker-Planck approach

    The spin torque switching rate of an in-plane magnetized system in the presence of an applied field is derived by solving the Fokker-Planck equation. It is found that three scaling currents are necessary to describe the current dependence of the switching rate in the low-current limit. The dependences of these scaling currents on the applied field strength are also studied

  3. Role of arachidonic acid in hyposmotic membrane stretch-induced increase in calcium-activated potassium currents in gastric myocytes

    Meng YANG; Wen-xie XU; Xing-lan LI; Hui-ying XU; Jia-bin SUN; Bin MEI; Hai-feng ZHENG; Lian-hua PIAO; De-gang XING; Zhai-liu LI

    2005-01-01

    Aim: To study effects of arachidonic acid (AA) and its metabolites on the hyposmotic membrane stretch-induced increase in calcium-activated potassium currents (IKCa) in gastric myocytes. Methods: Membrane currents were recorded by using a conventional whole cell patch-clamp technique in gastric myocytes isolated with collagenase. Results: Hyposmotic membrane stretch and AA increased both IK(Ca) and spontaneous transient outward currents significantly.Exogenous AA could potentiate the hyposmotic membrane stretch-induced increase in IK(Ca). The hyposmotic membrane stretch-induced increase in IK(Ca) was significantly suppressed by dimethyleicosadienoic acid (100 μmol/L in pipette solution), an inhibitor of phospholipase A2. Nordihydroguaiaretic acid, a lipoxygenase inhibitor, significantly suppressed AA and hyposmotic membrane stretch-induced increases in IK(Ca). External calcium-free or gadolinium chloride, a blocker of stretch-activated channels, blocked the AA-induced increase in IK(Ca) significantly, but it was not blocked by nicardipine, an L-type calcium channel blocker. Ryanodine, a calcium-induced calcium release agonist, completely blocked the AA-induced increase in IK(Ca); however, heparin, a potent inhibitor of inositol triphosphate receptor, did not block the AA-induced increase in IK(Ca). Conclusion:Hyposmotic membrane stretch may activate phospholipase A2, which hydrolyzes membrane phospholipids to ultimately produce AA; AA as a second messenger mediates Ca2+ influx, which triggers Ca2+-induced Ca2+ release and elicits activation of IK(Ca) in gastric antral circular myocytes of the guinea pig.

  4. Mechanochemical approach for selective deactivation of external surface acidity of ZSM-5 zeolite catalyst.

    Inagaki, Satoshi; Sato, Koki; Hayashi, Shunsuke; Tatami, Junichi; Kubota, Yoshihiro; Wakihara, Toru

    2015-03-01

    The acid sites associated with the external surface of zeolite particles are responsible for undesirable consecutive reactions, such as isomerization, alkylation, and oligomerization, resulting in a lower selectivity to a target product; therefore, the selective modification (deactivation) of the external surface of zeolite particles has been an important issue in zeolite science. Here, a new method for surface deactivation of zeolite catalyst was tested via a mechanochemical approach using powder composer. Postsynthetic mechanochemical treatment of ZSM-5 zeolite causes a selective deactivation of catalytically active sites existing only on the external surface, as a potentially useful catalyst for highly selective production of p-xylene. PMID:25654542

  5. Has Stewart approach improved our ability to diagnose acid-base disorders in critically ill patients?

    Masevicius, Fabio D; Dubin, Arnaldo

    2015-01-01

    The Stewart approach-the application of basic physical-chemical principles of aqueous solutions to blood-is an appealing method for analyzing acid-base disorders. These principles mainly dictate that pH is determined by three independent variables, which change primarily and independently of one other. In blood plasma in vivo these variables are: (1) the PCO2; (2) the strong ion difference (SID)-the difference between the sums of all the strong (i.e., fully dissociated, chemically nonreacting...

  6. Application of the Generic Modeling Template Approach to Unsaturated Fatty Acid Oxidation and Crystallization Systems

    Fedorova, Marina; Papadakis, Emmanouil; Meisler, Kresten Troelstrup; Sin, Gürkan; Gani, Rafiqul

    In this work, a couple of applications of the template-based approach for model development are presented. The computer-aided template concept has been developed based on a model decomposition technique and has been implemented as a software tool, which provides a user-friendly interface for...... following the modelling workflow steps, guidance through the steps , as well as providing additional information and comments. The application of the tool is highlighted with two case studies: oxidation of unsaturated acid with hydrogen peroxide and modeling of a crystal lization operation for the...... paracetamol-ethanol system....

  7. A modified approach for rapid determination of the quality of industrially produced P-33 orthophosphoric acid preparations

    In this work we have developed an approach to rapidly estimate the quality of P-33 labeled Orthophosphoric Acid (carrier free) in industrial production. The method was created to determine the values of specific radioactivity for both Orthophosphoric acid and gamma-Adenosine 5'-Triphosphate (ATP) by means of enzymatic ATP synthesis in equal molar ratio conditions for two main substrates (radioactive Orthophosphoric acid and ADP) with following chromatography of the reaction mixture on the PEI-cellulose micro column

  8. Stomatal response to abscisic Acid is a function of current plant water status.

    Tardieu, F; Davies, W J

    1992-02-01

    We investigated, under laboratory and field conditions, the possibility that increasing abscisic acid (ABA) concentrations and decreasing water potentials can interact in their effects on stomata. One experiment was carried out with epidermal pieces of Commelina communis incubated in media with a variety of ABA and polyethylene glycol concentrations. In the media without ABA, incubation in solutions with water potentials between -0.3 and -1.5 megapascals had no significant effect on stomatal aperture. Conversely, the sensitivity of stomatal aperture to ABA was trebled in solutions at -1.5 megapascals compared with sensitivity at -0.3 megapascals. The effect of the change in sensitivity was more important than the absolute effect of ABA at the highest water potential. In a field experiment, sensitivity of maize stomatal conductance to the concentration of ABA in the xylem sap varied strongly with the time of the day. We consider that the most likely explanation for this is the influence of a change in leaf or epidermal water potential that accompanies an increase in irradiance and saturation deficit as the day progresses. These observations suggest that epidermal water relations may act as a modulator of the responses of stomata to ABA. We argue that such changes must be taken into account in studies or modeling of plant responses to drought stress. PMID:16668674

  9. Current status and perspectives of neurobehavioral approaches in guideline—oriented animal testing

    TakaH

    2002-01-01

    This presentation aims to overview the current status and perspective of behavioral approaches used in guideline-oriented toxicological studies for agricultural chemicals.Guidelines revised recently (MAFF,OECD,EPA) require sytematic observation of non-learning behavior using defined scales.The observational endpoints are organized into a battery (e.g.functional observational battery,FOB) and inculde home-cage and open-field observation of behavior reactivity to various stimuli(e.g.auditory,tactile,visual),grip strength,and motor activity under a novel environment.The outline of FOB will be illustrated and discussed in the first half of the presentation.One social concern in neurotoxicology is the impact of chemical exposure on cnognitive functions such as learning and memory as well as non-learning behavior.Guidelines describe the necessity of learning and memory tests when other data suggest potential effects on brain function,even though little information regarding cognitive status other than brain pathology can be obtained with FOB.This discrepancy arises from the lack of a simple method compatible with regular studies.One candidate method is fear-induced freezing of rats conditioned to context and auditory cue(Kim & Fanselow,1992).In order to evaluate this paradigm as a screening method,the effects of trimethyltin chloride (TMT) have been studied.Prior to the study,it has been characterized that oral administration of TMT to rats produces excitatory clinical signs and massive neural cell death in the hippocampal CA1 and CA3 regions at lethal dose(8mg·kg-1),but not any abnormalities at sub-lethal doses (4mg·kg-1 or less).Oral administration of TMT at a sub-lethal dose produced a significant decrease in freezing time to the context (hippocampal-dependent measure),but not to the auditory cue.Administration of TMT at a sublethal dose significantly inhibited long-term potentiation in the CA1,but not in the dentate gyrus.These results suggest that the model can be

  10. High Tc Superconducting Materials for Strong Current Applications: Approach at the First Stage

    JIN Jian-xun

    2007-01-01

    Strong current and large-scale application is the most important prospect of high Tc superconductors (HTS). Practical HTS samples in various forms have been produced with high critical currents operated at economic cryogenic temperatures. Engineering applications of those HTS materials have been studied with various HTS prototype devices. The applicable HTS materials produced in different forms are verified in this paper with regard to their strong current characterizations, and the HTS applications are summarized along with the HTS prototypes made.

  11. A simple approach to the prediction of electrophoretic mobilities of diverse organic acids

    Based on the principle of separation by capillary electrophoresis, three simple molecular structural descriptors, the number of acid groups (NG), number of atoms (NA) and molecular weight (MW) were employed to model the molecular structure-electrophoretic mobility relationship with the general form of μ 0 = aNG/(bNA k + cMW k), where the value of k ranges from 1/3 to 2/3 depending on the magnitude of molecular weight. The absolute electrophoretic mobilities (μ 0) of three diverse data sets including carboxylic acids, sulfonic acids and peptides were investigated. Each data set was randomly divided into a training set for model generation and a test set for prediction test. The absolute average relative deviations (AARD and AARDP) of the training set and the test set are 7.21% and 7.53% for data set 1, 1.99% and 1.96% for data set 2, 3.25% and 3.95% for data set 3, respectively. Compared to the quantitative structure-mobility relationship (QSMR) models reported in the literature, the approach proposed in this study is much simpler in terms of the calculation of structural descriptors and the interpretation of the physicochemical meaning of the models

  12. A dissected ring current model for assessing magnetic aromaticity: a general approach for both organic and inorganic rings.

    Foroutan-Nejad, Cina; Shahbazian, Shant; Feixas, Ferran; Rashidi-Ranjbar, Parviz; Solà, Miquel

    2011-08-01

    A model based on classical electrodynamics is used to measure the strength of ring currents of different molecular orbitals, i.e., σ- and π-orbitals, and characteristics of ring current loops, i.e., ring current radii and height of current loops above/below the ring planes, among a number of organic as well as inorganic molecules. For the π-current, the present model represents an improvement of previous approaches to determine ring current intensity. It is proven that the present model is more precise than previous models as they could not explain presence of the minimum in the plot of NICS(πzz) versus distance close to the ring plane. Variations in the charge of molecules and the types of constituent atoms of each species affect the ring current radii of both σ- and π-current loops as well as the height of π-current loops above/below the ring plane. It is suggested that variation in the distribution of the one-electron density in different systems is the main source of differences of the ring current characteristics. PMID:21598277

  13. In-stream chemical neutralization: A whole watershed approach to mitigating acid mine drainage

    The North Branch of the Potomac River is adversely affected by acid mine drainage (AMD) throughout its entire length. As an alternative to mine-mouth treatment methods an in-stream AMD-neutralization demonstration program for an approximately 25-mile segment of the North Branch of the Potomac River was designed and implemented. This river segment was ranked as the highest priority site in Maryland for a demonstration project owing to its combination of very poor water quality and excellent potential for supporting a recreational sport fishery in the absence of toxic metal and acid loadings. A whole-watershed approach employing Scandinavian doser technologies and calcium carbonate neutralizing agents is the basis for the North Branch Potomac River demonstration project. The project involves four phases: feasibility (1), design (2), implementation (3), and monitoring (4). This watershed approach to mitigating AMD is expected to restore circumneutrial water quality and to promote desirable fishery resources throughout the mainstem and selected tributaries of the North Branch of the Potomac River Upstream of Jennings Randolph Dam. This paper summarizes Phases 1--3 of the demonstration project

  14. Preliminary assessment of the current impact and potential risk of acidic deposition on walleye populations in Ontario

    Wales, D.L.; Liimatainen, V.A.

    1987-01-01

    Netting survey and field bioassay data were used to determine a pH threshold for survival of walleye. Established pH thresholds were then used to assess the current impact and potential risk of acidic deposition on walleye populations in Ontario. Extinction of walleye appeared to occur in lakes with pH < 5.5. Some losses may also have occurred in lakes with pH 5.5-6.0. An estimated 0.3% (number of lakes (N)=12) of the Ontario walleye lakes currently have pH < 5.5 and have likely lost walleye populations. A further 1.5% (N=60) of the lakes have pH 5.5-6.0 and may show signs of acidification stress. An estimated 2.0% (N=79) of the province's walleye lakes have very low alkalinities (0.0-2.0 mg/l) and are classified as extremely sensitive to continued high deposition of acidic precipitation. 19 refs., 4 figs., 7 tabs.

  15. A novel approach to enhancing ganoderic acid production by Ganoderma lucidum using apoptosis induction.

    Bang-Jau You

    Full Text Available Ganoderma lucidum is one of most widely used herbal medicine and functional food in Asia, and ganoderic acids (GAs are its active ingredients. Regulation of GA biosynthesis and enhancing GA production are critical to using G. lucidum as a medicine. However, regulation of GA biosynthesis by various signaling remains poorly understood. This study investigated the role of apoptosis signaling on GA biosynthesis and presented a novel approach, namely apoptosis induction, to increasing GA production. Aspirin was able to induce cell apoptosis in G. lucidum, which was identified by terminal deoxynucleotidyl transferase mediated dUPT nick end labeling assay positive staining and a condensed nuclear morphology. The maximum induction of lanosta-7,9(11, 24-trien-3α-01-26-oic acid (ganoderic acid 24, GA24 production and total GA production by aspirin were 2.7-fold and 2.8-fold, respectively, after 1 day. Significantly lower levels of GA 24 and total GAs were obtained after regular fungal culture for 1.5 months. ROS accumulation and phosphorylation of Hog-1 kinase, a putative homolog of MAPK p38 in mammals, occurred after aspirin treatment indicating that both factors may be involved in GA biosynthetic regulation. However, aspirin also reduced expression of the squalene synthase and lanosterol synthase coding genes, suggesting that these genes are not critical for GA induction. To the best of our knowledge, this is the first report showing that GA biosynthesis is linked to fungal apoptosis and provides a new approach to enhancing secondary metabolite production in fungi.

  16. Furan oxidation based cross-linking: a new approach for the study and targeting of nucleic acid and protein interactions.

    Carrette, L L G; Gyssels, E; De Laet, N; Madder, A

    2016-01-28

    Furan mediated nucleic acid cross-linking, initially developed for DNA interstrand duplex cross-linking, has matured into a versatile tool for the study of protein and nucleic acid interactions, ready to face its applications. The methodology was initially developed for easy and clean chemical generation of DNA interstrand cross-linked duplexes, but has been further expanded for use with other probes, targets and triggers, now allowing mild biologically significant cross-linking with potential therapeutic benefit. It was shown that the methodology could be repurposed for RNA interstrand cross-linking, which is very relevant in today's antisense approaches or miRNA target identification endeavors. This further illustrates the furan oxidation method's generality and mildness, especially when using red light for oxidation. A complementary antigene approach has been explored through duplex targeting with furan modified triplex forming oligonucleotides (TFOs) and DNA binding proteins. Also targeting of peptides and proteins by furan-modified DNA and peptides has been explored. Thorough methodology examination exploring variable reaction conditions in combination with a series of different furan-modified building blocks and application of different activation signals resulted in a detailed understanding of the mechanisms involved and factors influencing the yield and selectivity of the reaction. In order to draw the bigger picture of the scope and limitations of furan-oxidation cross-linking, we here provide a unique side by side comparison and discussion of our published data, supplemented with unpublished results, providing a clear performance report of the currently established furan toolbox and its application potential in various biomacromolecular complexes. PMID:26679922

  17. The Pliocene to recent history of the Kuroshio and Tsushima Currents: a multi-proxy approach

    Gallagher, Stephen J.; Kitamura, Akihisa; Iryu, Yasufumi; Itaki, Takuya; Koizumi, Itaru; Hoiles, Peter W.

    2015-12-01

    The Kuroshio Current is a major western boundary current controlled by the North Pacific Gyre. It brings warm subtropical waters from the Indo-Pacific Warm Pool to Japan exerting a major control on Asian climate. The Tsushima Current is a Kuroshio offshoot transporting warm water into the Japan Sea. Various proxies are used to determine the paleohistory of these currents. Sedimentological proxies such as reefs, bedforms, sediment source and sorting reveal paleocurrent strength and latitude. Proxies such as coral and mollusc assemblages reveal past shelfal current activity. Microfossil assemblages and organic/inorganic geochemical analyses determine paleo- sea surface temperature and salinity histories. Transportation of tropical palynomorphs and migrations of Indo-Pacific species to Japanese waters also reveal paleocurrent activity. The stratigraphic distribution of these proxies suggests the Kuroshio Current reached its present latitude (35 °N) by ~3 Ma when temperatures were 1 to 2 °C lower than present. At this time a weak Tsushima Current broke through Tsushima Strait entering the Japan Sea. Similar oceanic conditions persisted until ~2 Ma when crustal stretching deepened the Tsushima Strait allowing inflow during every interglacial. The onset of stronger interglacial/glacial cycles ~1 Ma was associated with increased North Pacific Gyre and Kuroshio Current intensity. This triggered Ryukyu Reef expansion when reefs reached their present latitude (~31 °N), thereafter the reef front advanced (~31 °N) and retreated (~25 °N) with each cycle. Foraminiferal proxy data suggests eastward deflection of the Kuroshio Current from its present path at 24 °N into the Pacific Ocean due to East Taiwan Channel restriction during the Last Glacial Maximum. Subsequently Kuroshio flow resumed its present trajectory during the Holocene. Ocean modeling and geochemical proxies show that the Kuroshio Current path may have been similar during glacials and interglacials, however

  18. CURRENT STATUS AND POTENTIAL OF BIOTECHNOLOGICAL APPROACHES FOR RICE BLAST DISEASE IN THE RICE CULTIVATION TECHNOLOGY

    Petenko A. I.; Volkova S. A.

    2014-01-01

    Rice blast caused by Pyricularia oryzae is a major disease affecting rice production grown in upland and wetland rice. Application of biotechnological approach to protect against the disease may be an alternative strategy to chemical control

  19. Rotor cage fault diagnosis in three-phase induction motors based on a current and virtual flux approach

    Pires, Dulce F. [Escola Sup. Tecnologia Setubal/Inst. Politecnico Setubal, Setubal (Portugal); Pires, V. Fernao [Escola Sup. Tecnologia Setubal/Inst. Politecnico Setubal, Setubal (Portugal)]|[LabSEI - Laboratorio de Sistemas Electricos Industriais, Setubal (Portugal); Martins, J.F. [CTS, Faculdade de Ciencias e Tecnologia/UNL, Lisboa (Portugal); Pires, A.J. [Escola Sup. Tecnologia Setubal/Inst. Politecnico Setubal, Setubal (Portugal)]|[LabSEI - Laboratorio de Sistemas Electricos Industriais, Setubal (Portugal)]|[CTS, Faculdade de Ciencias e Tecnologia/UNL, Lisboa (Portugal)

    2009-04-15

    This paper focuses on the detection of a rotor cage fault in a three-phase PWM feed induction motor. In inverter-fed machines there are some difficulties for the detection of a rotor cage fault. These difficulties are due to the fault signature that will be contained in the currents or voltages applied to the machine. In this way, a new approach based on the current and a virtual flux is proposed. The use of the virtual flux allows the improving of the signal to noise ratio. This approach also allows the identification of a rotor cage fault independently of the type of control used in the ac drive. The theoretical principle of this method is discussed. Simulation and experimental results are presented in order to show the effectiveness of the proposed approach. (author)

  20. A Systems Genetics Approach Identifies Gene Regulatory Networks Associated with Fatty Acid Composition in Brassica rapa Seed.

    Basnet, Ram Kumar; Del Carpio, Dunia Pino; Xiao, Dong; Bucher, Johan; Jin, Mina; Boyle, Kerry; Fobert, Pierre; Visser, Richard G F; Maliepaard, Chris; Bonnema, Guusje

    2016-01-01

    Fatty acids in seeds affect seed germination and seedling vigor, and fatty acid composition determines the quality of seed oil. In this study, quantitative trait locus (QTL) mapping of fatty acid and transcript abundance was integrated with gene network analysis to unravel the genetic regulation of seed fatty acid composition in a Brassica rapa doubled haploid population from a cross between a yellow sarson oil type and a black-seeded pak choi. The distribution of major QTLs for fatty acids showed a relationship with the fatty acid types: linkage group A03 for monounsaturated fatty acids, A04 for saturated fatty acids, and A05 for polyunsaturated fatty acids. Using a genetical genomics approach, expression quantitative trait locus (eQTL) hotspots were found at major fatty acid QTLs on linkage groups A03, A04, A05, and A09. An eQTL-guided gene coexpression network of lipid metabolism-related genes showed major hubs at the genes BrPLA2-ALPHA, BrWD-40, a number of seed storage protein genes, and the transcription factor BrMD-2, suggesting essential roles for these genes in lipid metabolism. Three subnetworks were extracted for the economically important and most abundant fatty acids erucic, oleic, linoleic, and linolenic acids. Network analysis, combined with comparison of the genome positions of cis- or trans-eQTLs with fatty acid QTLs, allowed the identification of candidate genes for genetic regulation of these fatty acids. The generated insights in the genetic architecture of fatty acid composition and the underlying complex gene regulatory networks in B. rapa seeds are discussed. PMID:26518343

  1. A new approach for modeling of dark current characteristics of quantum wire infrared photodetectors

    H. Barickaby; A. Zarifkar; M. H. Sheikhi

    2011-01-01

    In order to study the dark current characteristics in a quantum wire infrared photodetector (QRIP), the average number of electrons in quantum wires (QRs) must be got, which is mostly too complicated. In this paper we give a simple formula to calculate the average number of carriers in a quantum wire (QR) that can be easily evaluated by mathematical softwares, and then we use this formula to study dark current characteristics ora quantum wire infrared photodetector (QRIP).

  2. A hybrid approach to the solution of open boundary eddy current problems under TM field excitation

    This paper extends the modified hybrid integrodifferential finite element (IDFE) Green's function method to the solution of 2D unbounded eddy current problems under transverse magnetic (TM) field excitation. To illustrate this formulation, the magnetic vector potentials (MVP) of a solid and a hollow conducting cylinder under TM field excitations are computed. Current distributions and power losses are obtained. The formulation is validated by comparing calculated results with analytic solutions

  3. Leadership education in Sweden 2010 and its connection to current values : an institutional approach

    Östling, Peter; Torkaman, Nima

    2010-01-01

    This study is a comparative study with the purpose of connecting the Swedish leadership education with the current social values. By utilizing a historical as well as a broad theoretical perspective we wish to create a clear understanding of the current market. The study made use of both the quantitative and the qualitative research methodologies through the use of interview. Ten of the most prominent leadership educators in the Swedish business sector were interviewed to gain credible insigh...

  4. Potential Approach of Microbial Conversion to Develop New Antifungal Products of Omega-3 Fatty Acids

    Omega-3/('-3) or n-3 fatty acids are a family of unsaturated fatty acids that have in common a final carbon-carbon double bond in the n-3 position. n-3 Fatty acids which are important in human nutrition are: a-linolenic acid (18:3, n-3; ALA), eicosapentaenoic acid (20:5, n-3; EPA), and docosahexaen...

  5. Transient motor current signature analysis via modulus of the continuous complex wavelet: A pattern approach

    Highlights: • Transient MCSA detects motor faults via time–frequency analysis of the current. • The modulus of the CCWT shows the current harmonics in the time–frequency plane. • The choice of the DOG as mother wavelet is made after a comparative analysis. • Each motor fault harmonics displays a different pattern in the generated image. • A commercial motor with a rotor broken bar has been used to present the method. - Abstract: In this paper a new method to perform Transient Motor Current Signature analysis (TMCSA), based on the Continuous Complex Wavelet Transform (CCWT) of the line current, is presented. TMCSA is a powerful online method for diagnosing motor faults. Unlike traditional MCSA methods, based on the Fourier Transform (FT) of the stator currents in stationary regime, it can identify not only the presence of current harmonics that are characteristic of each motor fault, but also their unique time–frequency evolution pattern. This feature greatly increases its reliability, helping to discard non-fault related harmonics like those generated by periodic loads or voltage unbalances. In the case of a machine with broken bars, the representation in the time–frequency plane of the left sideband harmonic during the startup transient (LSHst) constitutes such a clear fault pattern. Mathematical tools that are able to characterize non-stationary signals are needed in TMCSA, such as the CCWT. It is a highly redundant transformation of the current signal into the time–frequency domain, and its modulus is used in this paper to generate a high resolution graphic pattern of the fault. Experimental results obtained on a 1.1 kW three-phase squirrel-cage induction motor with broken bars are discussed

  6. A new approach to control a deflection of an electroplated microstructure: dual current electroplating methods

    We propose and demonstrate a simple and novel method to control the deflection in a suspended microstructure by using a dual current electroplating (DuCE) method. The key concept of this method is to divide the structure into two layers—a bottom layer and a top layer—and then apply respective current densities in electroplating to those two layers while all other conditions are kept the same. In addition to a flat structure, the direction of structure bending is freely controlled by virtue of the DuCE method. Cantilever Ni beams with a length of 400 µm, which were electroplated by the conventional single current electroplating method, bent downward with a deflection of 3.4 µm. On the contrary, by the DuCE method, cantilever beams with a length of 400 µm showed an almost flat structure as desired. (The current densities of the bottom layer, the top layer, and the ratio of the two current densities, are 0.15, 1.24 A dm−2, and 8.3, respectively.) Consequently, a nickel electroplated spiral structure with a length of 8600 µm was suspended flat with an end deflection of less than 0.7 µm (the ratio between the deflection and length is 0.007%). This work therefore represents the unprecedented ultra-long suspended microstructure with submicrometer deflection. (paper)

  7. Current Regulations and Guidance - New Approaches for Risk-Informed Low-Level Radioactive Waste Management

    This paper presents the historical foundations and future challenges for commercial low-level radioactive waste (LLRW) management in the United States. LLRW has been managed at government facilities since the beginning of the nuclear age and in the commercial sector since the early 1960's. Over the intervening years many technical, management and regulatory changes have occurred. Significant progress has been made in waste form, waste packaging and in recognizing radionuclides important to performance of disposal technologies and disposal facilities. This presentation will examine approaches using existing regulations and risk-informed approaches to improve guidance, licensing and management of LLRW. (authors)

  8. Master Equation Approach to Current-Voltage Characteristics of Solar Cells

    Oh, Sangchul; Zhang, Yiteng; Alharbi, Fahhad; Kais, Sabre

    2015-03-01

    The current-voltage characteristics of solar cells is obtained using quantum master equations for electrons, holes, and excitons, in which generation, recombination, and transport processes are taken into account. As a first example, we simulate a photocell with a molecular aggregate donor to investigate whether a delocalized quantum state could enhance the efficiency. As a second example, we calculate the current-voltage characteristics of conventional p-n junction solar cells and perovskite solar cells using the master equation. The connection between the drift-diffusion model and the master equation method is established. The short-circuit current and the open-circuit voltage are calculated numerically as a function of the intensity of the sunlight and material properties such as energy gaps, diffusion constants, etc.

  9. Current Conservation in Electrodisintegration of a Bound System in the Bethe–Salpeter Approach

    Using our solutions of the Bethe–Salpeter equation with OBE kernel in Minkowski space both for the bound and scattering states, we calculate the transition form factors for electrodisintegration of the bound system which determine the electromagnetic current J of this process. Special emphasis is put on verifying the gauge invariance which should manifest itself in the current conservation. We find that for any value of the momentum transfer q the contributions of the plane wave and the final state interaction to the quantity J · q cancel each other thus providing J · q = 0. However, this cancellation, is obtained only if the initial BS amplitude (bound state), the final one (scattering state) and the current operator are strictly consistent with each other. A reliable result for the transition form factor can be found only in this case. (author)

  10. An Approach to Model Earth Conductivity Structures with Lateral Changes for Calculating Induced Currents and Geoelectric Fields during Geomagnetic Disturbances

    Bo Dong

    2015-01-01

    Full Text Available During geomagnetic disturbances, the telluric currents which are driven by the induced electric fields will flow in conductive Earth. An approach to model the Earth conductivity structures with lateral conductivity changes for calculating geoelectric fields is presented in this paper. Numerical results, which are obtained by the Finite Element Method (FEM with a planar grid in two-dimensional modelling and a solid grid in three-dimensional modelling, are compared, and the flow of induced telluric currents in different conductivity regions is demonstrated. Then a three-dimensional conductivity structure is modelled and the induced currents in different depths and the geoelectric field at the Earth’s surface are shown. The geovoltages by integrating the geoelectric field along specific paths can be obtained, which are very important regarding calculations of geomagnetically induced currents (GIC in ground-based technical networks, such as power systems.

  11. Enhancement of critical current of SiC and malic acid codoped MgB2/Fe wires

    Li, W. X.; Chen, R. H.; Xu, X.; Hu, Y. M.; Zhu, M. Y.; Li, Y.; Dou, S. X.

    2015-09-01

    The influences of microstructure, connectivity, and disorder on the critical current density, Jc, are discussed to clarify the different mechanisms of Jc(H) in different magnetic field ranges for in situ and combined in situ/ex situ MgB2/Fe wires with nano SiC and malic acid codoping. Sintering temperature plays a very important role in the electromagnetic properties at different temperatures and under various magnetic fields. Connectivity, upper critical field, Hc2, and irreversibility field, Hirr, are studied to demonstrate the mechanism of Jc dependence on magnetic field. The combined in situ/ex situ process is proved to be a promising technique for fabrication of practical MgB2 wires.

  12. Current Research Of Hyaluronic Acid%透明质酸的研究现状综述

    宋磊; 王腾飞

    2012-01-01

    透明质酸(hyaluronic acid,简称HA)是由葡萄糖醛酸和N-乙酰氨基葡萄糖胺为双糖单位交替连接而成的粘多糖物质。本文论述了透明质酸的特性、应用、制备等研究现状,分析了目前存在的主要问题及解决途径,并对其前景进行了展望。%Hyaluronic acid(HA)is a linear polysaccharide chain composed of alternating glucuronic acid(GlcA) and N-acetylglucosamine(GlcNAc) moieties.In this paper,We described the current reasearch of hyaluronic acid in its production.In addition,the main problems in HA production were also discussed and the methods were put forward for the research.Moreover,the prospect of this research was proposed.

  13. A combinatorial approach to detect coevolved amino acid networks in protein families of variable divergence.

    Julie Baussand

    2009-09-01

    Full Text Available Communication between distant sites often defines the biological role of a protein: amino acid long-range interactions are as important in binding specificity, allosteric regulation and conformational change as residues directly contacting the substrate. The maintaining of functional and structural coupling of long-range interacting residues requires coevolution of these residues. Networks of interaction between coevolved residues can be reconstructed, and from the networks, one can possibly derive insights into functional mechanisms for the protein family. We propose a combinatorial method for mapping conserved networks of amino acid interactions in a protein which is based on the analysis of a set of aligned sequences, the associated distance tree and the combinatorics of its subtrees. The degree of coevolution of all pairs of coevolved residues is identified numerically, and networks are reconstructed with a dedicated clustering algorithm. The method drops the constraints on high sequence divergence limiting the range of applicability of the statistical approaches previously proposed. We apply the method to four protein families where we show an accurate detection of functional networks and the possibility to treat sets of protein sequences of variable divergence.

  14. Path to facilitate the prediction of functional amino acid substitutions in red blood cell disorders--a computational approach.

    Rajith B

    Full Text Available BACKGROUND: A major area of effort in current genomics is to distinguish mutations that are functionally neutral from those that contribute to disease. Single Nucleotide Polymorphisms (SNPs are amino acid substitutions that currently account for approximately half of the known gene lesions responsible for human inherited diseases. As a result, the prediction of non-synonymous SNPs (nsSNPs that affect protein functions and relate to disease is an important task. PRINCIPAL FINDINGS: In this study, we performed a comprehensive analysis of deleterious SNPs at both functional and structural level in the respective genes associated with red blood cell metabolism disorders using bioinformatics tools. We analyzed the variants in Glucose-6-phosphate dehydrogenase (G6PD and isoforms of Pyruvate Kinase (PKLR & PKM2 genes responsible for major red blood cell disorders. Deleterious nsSNPs were categorized based on empirical rule and support vector machine based methods to predict the impact on protein functions. Furthermore, we modeled mutant proteins and compared them with the native protein for evaluation of protein structure stability. SIGNIFICANCE: We argue here that bioinformatics tools can play an important role in addressing the complexity of the underlying genetic basis of Red Blood Cell disorders. Based on our investigation, we report here the potential candidate SNPs, for future studies in human Red Blood Cell disorders. Current study also demonstrates the presence of other deleterious mutations and also endorses with in vivo experimental studies. Our approach will present the application of computational tools in understanding functional variation from the perspective of structure, expression, evolution and phenotype.

  15. The "Magic Cure" A Review of the Current Controversial Approaches for Treating Learning Disabilities.

    Silver, Larry B.

    1987-01-01

    In view of popular press coverage of controversial approaches to treating learning disabilities, the article briefly reviews evidence concerning the following: neurophysiological retraining (patterning, optometric visual training, cerebellar-vestibular remediation, and applied kinesiology); and orthomolecular medicine (concerning megavitamins,…

  16. Approaches to Learning with Media and Media Literacy Education--Trends and Current Situation in Germany

    Tulodziecki, Gerhard; Grafe, Silke

    2012-01-01

    German approaches to media literacy education are concerned with the questions, how the variety of media can be used in a meaningful way for learning and teaching and what educational tasks result from the extensive use of media. Considering these questions there are various conceptual ideas, research and development projects as well as…

  17. A Phenomenological Approach to Experiences with Technology: Current State, Promise, and Future Directions for Research

    Cilesiz, Sebnem

    2011-01-01

    In this paper I conceptualize experiences with technology as an object of study for educational technology research and propose phenomenology as a highly suitable method for studying this construct. I begin by reviewing existing research focusing on the construct of experiences with technology and the approaches utilized for its study. To augment…

  18. Current Cognitive Distortion Theory and Research: An Internalist Approach to Cognition

    Gannon, Theresa A.

    2009-01-01

    This review examines contemporary cognitive distortion theory and research relating to sexual offenders. In particular, this review highlights that researchers--to date--have tended to adopt an internalist approach to sexual offenders' cognition which views offence-supportive cognitive activity as occurring solely within the mind. This review…

  19. Current Approaches to the Assessment of Graphic Design in a Higher Education Context

    Giloi, Susan; du Toit, Pieter

    2013-01-01

    This article provides an overview of the current trends in assessment practice within the field of graphic design. The demands placed on educators to apply sound assessment practice for Higher Education subjects is as intense in the field of graphic design as in any other. Forcing the assessment of creative visual work into existing assessment…

  20. Current training on the basics of robotic surgery in the Netherlands: Time for a multidisciplinary approach?

    W. Brinkman (Willem); I. de Angst (Isabel); H.W.R. Schreuder (Henk); B. Schout (Barbara); W.A. Draaisma (Werner); L.M. Verweij (Lisanne); A.J.M. Hendrikx (A. J M); H.G. van der Poel (Henk G.)

    2016-01-01

    textabstractIntroduction: The following research questions were answered: (1) What are the training pathways followed by the current robot professionals? (2) Are there any differences between the surgical specialties in robot training and robot use? (3) What is their opinion about multidisciplinary

  1. On wind Turbine failure detection from measurements of phase currents: a permutation entropy approach

    Ram, Sumit Kumar; Molinas, Marta

    2016-01-01

    This article presents the applicability of Permutation Entropy based complexity measure of a time series for detection of fault in wind turbines. A set of electrical data from one faulty and one healthy wind turbine were analysed using traditional FastFourier analysis in addition to Permutation Entropy analysis to compare the complexity index of phase currents of the two turbines over time. The 4 seconds length data set did not reveal any low frequency in the spectra of currents, neither did they show any meaningful differences of spectrum between the two turbine currents. Permutation Entropy analysis of the current waveforms of same phases for the two turbines are found to have different complexity values over time, one of them being clearly higher than the other. The work of Yan et. al. in has found that higher entropy values related to thepresence of failure in rotary machines in his study. Following this track, further efforts will be put into relating the entropy difference found in our study to possible...

  2. Employability and Employment Approaches: Currently Practiced in Independent Living Programs. A Resource Document.

    Means, Bob; And Others

    This document provides descriptions of employment interventions as a resource for use in initiating or expanding employment services for individuals with disabilities. The document presents abstracts of 40 employability/employment interventions and practices currently in use by independent living programs throughout the United States. The…

  3. Current trends in the pharmaceutical industry--a case study approach.

    Rusu, Alexandru; Kuokkanen, Katja; Heier, Annabelle

    2011-10-01

    This commentary offers an overview of some current trends of the pharmaceutical industry drawing on examples taken from the analysis of four companies (Pfizer, Merck, Novo Nordisk, Crucell). The very brief analysis looks at diversification paths, pipeline management strategies, generic competition as well as corporate social responsibility policies. PMID:21782941

  4. Evaluation of Current Approaches to Stream Classification and a Heuristic Guide to Developing Classifications of Integrated Aquatic Networks

    Melles, S. J.; Jones, N. E.; Schmidt, B. J.

    2014-03-01

    Conservation and management of fresh flowing waters involves evaluating and managing effects of cumulative impacts on the aquatic environment from disturbances such as: land use change, point and nonpoint source pollution, the creation of dams and reservoirs, mining, and fishing. To assess effects of these changes on associated biotic communities it is necessary to monitor and report on the status of lotic ecosystems. A variety of stream classification methods are available to assist with these tasks, and such methods attempt to provide a systematic approach to modeling and understanding complex aquatic systems at various spatial and temporal scales. Of the vast number of approaches that exist, it is useful to group them into three main types. The first involves modeling longitudinal species turnover patterns within large drainage basins and relating these patterns to environmental predictors collected at reach and upstream catchment scales; the second uses regionalized hierarchical classification to create multi-scale, spatially homogenous aquatic ecoregions by grouping adjacent catchments together based on environmental similarities; and the third approach groups sites together on the basis of similarities in their environmental conditions both within and between catchments, independent of their geographic location. We review the literature with a focus on more recent classifications to examine the strengths and weaknesses of the different approaches. We identify gaps or problems with the current approaches, and we propose an eight-step heuristic process that may assist with development of more flexible and integrated aquatic classifications based on the current understanding, network thinking, and theoretical underpinnings.

  5. Current Approaches to Neuromodulation in Primary Headaches: Focus on Vagal Nerve and Sphenopalatine Ganglion Stimulation.

    Puledda, Francesca; Goadsby, Peter J

    2016-07-01

    Neuromodulation is a promising, novel approach for the treatment of primary headache disorders. Neuromodulation offers a new dimension in the treatment that is both easily reversible and tends to be very well tolerated. The autonomic nervous system is a logical target given the neurobiology of common primary headache disorders, such as migraine and the trigeminal autonomic cephalalgias (TACs). This article will review new encouraging results of studies from the most recent literature on neuromodulation as acute and preventive treatment in primary headache disorders, and cover some possible underlying mechanisms. We will especially focus on vagus nerve stimulation (VNS) and sphenopalatine ganglion (SPG) since they have targeted autonomic pathways that are cranial and can modulate relevant pathophysiological mechanisms. The initial data suggests these approaches will find an important role in headache disorder management going forward. PMID:27278441

  6. Risk assessment of mixtures of pesticides. Current approaches and future strategies

    Reffstrup, Trine Klein; Larsen, John Christian; Meyer, Otto A.

    2010-01-01

    The risk assessment of pesticide residues in food is based on toxicological evaluation of the single compounds and no internationally accepted procedure exists for evaluation of cumulative exposure to multiple residues of pesticides in crops, except for a few groups of pesticides sharing a group...... several approaches are available for the risk assessment of mixtures of pesticides. However, no single simple approach is available to judge upon potential interactions at the low doses that humans are exposed to from pesticide residues in food. In these cases, PBTK models could be useful as tools to...... assess combined tissue doses and to help predict potential interactions including thresholds for such effects. This would improve the quality of the risk assessment....

  7. Models of the impact of dengue vaccines: a review of current research and potential approaches.

    Johansson, Michael A; Hombach, Joachim; Cummings, Derek A T

    2011-08-11

    Vaccination reduces transmission of pathogens directly, by preventing individual infections, and indirectly, by reducing the probability of contact between infected individuals and susceptible ones. The potential combined impact of future dengue vaccines can be estimated using mathematical models of transmission. However, there is considerable uncertainty in the structure of models that accurately represent dengue transmission dynamics. Here, we review models that could be used to assess the impact of future dengue immunization programmes. We also review approaches that have been used to validate and parameterize models. A key parameter of all approaches is the basic reproduction number, R(0), which can be used to determine the critical vaccination fraction to eliminate transmission. We review several methods that have been used to estimate this quantity. Finally, we discuss the characteristics of dengue vaccines that must be estimated to accurately assess their potential impact on dengue virus transmission. PMID:21699949

  8. Prevention of Overweight and Obesity: How Effective is the Current Public Health Approach

    Jean Woo; Chan, Ruth S.M

    2010-01-01

    Obesity is a public health problem that has become epidemic worldwide. Substantial literature has emerged to show that overweight and obesity are major causes of co-morbidities, including type II diabetes, cardiovascular diseases, various cancers and other health problems, which can lead to further morbidity and mortality. The related health care costs are also substantial. Therefore, a public health approach to develop population-based strategies for the prevention of excess weight gain is o...

  9. Current diagnostic approach of bone tumors in childhood; Abordagem diagnostica atual dos tumores osseos na infancia

    Torre, Marcia Barbosa; Scatigno Neto, Andre [Sao Paulo Univ., SP (Brazil). Faculdade de Medicina. Hospital das Clinicas

    1995-09-01

    The authors analyze the magnetic resonance imaging (MRI) as the imaging modality of choice for evaluation of patients with bone tumors or soft tissue tumors. The advent of such a sensitive imaging modality is fortuitous and coincides with a recent change in the therapeutic approach to primary bone tumors. MRI is extremely valuable in monitoring the tumor response to the initial chemotherapy and is accurate defining the margins of tumor, facilitating planning of limb salvage surgical procedures. (author). 5 refs., 8 figs.

  10. A Self-Sensing Active Magnetic Bearing Based on a Direct Current Measurement Approach

    Du Rand, Carel P.; George van Schoor; Niemann, Andries C.

    2013-01-01

    Active magnetic bearings (AMBs) have become a key technology in various industrial applications. Self-sensing AMBs provide an integrated sensorless solution for position estimation, consolidating the sensing and actuating functions into a single electromagnetic transducer. The approach aims to reduce possible hardware failure points, production costs, and system complexity. Despite these advantages, self-sensing methods must address various technical challenges to maximize the performance the...

  11. Modeling of Internal Parameters of Massive Conductors Carrying Time-Varying Currents Using Integrodifferential Approach

    Doležel, Ivo; Karban, P.; Ulrych, B.

    Gliwice-Ustron : Politechnika Slaska, 2007, s. 31-32. ISBN 978-83-85940-29-6. [International Conference on Fundamentals of Electrotechnics and Circuit Theory SPETO’06 /30./. Gliwice-Ustron (PL), 23.05.2007-26.05.2007] R&D Projects: GA ČR GA102/05/0629 Institutional research plan: CEZ:AV0Z20570509 Keywords : internal parameters * integrodifferential approach * numerical analysis Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering www.icspeto.polsl.gliwice.pl

  12. Molecular Phytopathology: Current Approaches and Main Directions in Diagnostics of Woody Plant Diseases

    O. Yu. Baranov

    2014-01-01

    In the article the authors describe the prospects for diagnosis of woody plants diseases based on the use of modern methods of molecular plant pathology. The metagenomic approach based on the analysis of complex pathogens, including non-pathogenic microflora is described. The use the multicopy universal loci characterized by a number of advantages in determining taxonomic affiliation of infectious agents during phytopathological molecular analysis is proposed.

  13. Methodological Approach and Technological Framework to Break the Current Limitations of MOOC Model

    Fidalgo-Blanco, Ángel; Sein-Echaluce, María Luisa; Francisco José GARCÍA-PEÑALVO

    2015-01-01

    [EN]A methodological approach and technological framework are proposed to improve learning outcomes in Massive Open Online Courses (MOOCs), taking into account the distinguishing features of this kind of massive courses over traditional online courses. The proposed methodology integrates the learning strategies of xMOOCs and cMOOCs with adaptivity and knowledge management capabilities. In order to test the learning results of the methodology and the need of supporting technolog...

  14. Organic agriculture in Kenya : Focus on: Current approaches in chemical ecology using regionally adapted sustainable methods

    WINTER, EVA

    2013-01-01

    Kenya is an African developing country situated at the equator ranking 157 th of 177 countries in the human development index. Agriculture is next to tourism the most important economic sector with 24 % of the GDP. Poverty prevalence is highest with small holder farmers. A promissing approach to reduce this precarious condition is the implementation of organic agriculture. 1. Establishment of certified organic cash crop production for a domestic and/or an export market and 2. disseminati...

  15. Biorefinery approach for cassava-based industrial wastes: Current status and opportunities.

    Zhang, Ming; Xie, Li; Yin, Zhixuan; Khanal, Samir Kumar; Zhou, Qi

    2016-09-01

    Cassava, an important food crop, has been extensively employed as raw materials for various agri-industries to produce starch, bioethanol and other biobased products/chemicals. These cassava-based industries also generate large quantities of wastes/residues, rich in organic matter and suspended solids, and pose significant environmental issues. Their complex biochemical composition with high organic content endows them with a great potential for bioconversion into value-added products via biorefinery thereby providing economic and environmental sustainability to cassava industries. This state-of-the-art review covers the source, composition and characteristics of cassava industrial wastes and residues, and their bioconversion into value-added products, mainly biofuels (ethanol and butanol), biogas, biosurfactant, organic acids and other valuable biochemicals among others. This paper also outlines future perspectives with respect to developing more effective and efficient bioconversion processes for converting the cassava wastes and residues into high-value products. PMID:27117291

  16. Bringing trauma-informed practice to domestic violence programs: A qualitative analysis of current approaches.

    Wilson, Joshua M; Fauci, Jenny E; Goodman, Lisa A

    2015-11-01

    Three out of 10 women and 1 out of 10 men in the United States experience violence at the hands of an intimate partner-often with devastating costs. In response, hundreds of residential and community-based organizations have sprung up to support survivors. Over the last decade, many of these organizations have joined other human service systems in adopting trauma-informed care (TIC), an approach to working with survivors that responds directly to the effects of trauma. Although there have been various efforts to describe TIC in domestic violence (DV) programs, there is a need to further synthesize this discourse on trauma-informed approaches to better understand specific applications and practices for DV programs. This study aimed to address this gap. The authors of this study systematically identified key documents that describe trauma-informed approaches in DV services and then conducted a qualitative content analysis to identify core themes. Results yielded 6 principles (Establishing emotional safety, Restoring choice and control, Facilitating connection, Supporting coping, Responding to identity and context, and Building strengths), each of which comprised a set of concrete practices. Despite the common themes articulated across descriptions of DV-specific trauma-informed practices (TIP), we also found critical differences, with some publications focusing narrowly on individual healing and others emphasizing the broader community and social contexts of violence and oppression. Implications for future research and evaluation are discussed. (PsycINFO Database Record PMID:26594925

  17. The generalized BLM approach to fix scale-dependence in QCD: the current status of investigations

    Kataev, A L

    2014-01-01

    I present a brief review of the generalized Brodsky-Lepage-McKenzie (BLM) approaches to fix the scale-dependence of the renormalization group (RG) invariant quantities in QCD. At first, these approaches are based on the expansions of the coefficients of the perturbative series for the RG-invariant quantities in the products of the coefficients $\\beta_i$ of the QCD $\\beta$-function, which are evaluated in the MS-like schemes. As a next step all $\\beta_i$-dependent terms are absorbed into the BLM-type scale(s) of the powers of the QCD couplings. The difference between two existing formulations of the above mentioned generalizations based on the seBLM approach and the Principle of Maximal Conformality (PMC) are clarified in the case of the Bjorken polarized deep-inelastic scattering sum rule. Using the conformal symmetry-based relations for the non-singlet coefficient functions of the Adler D-function and of Bjorken polarized deep-inelastic scattering sum rules $C^{\\rm Bjp}_{\\rm NS}(a_s)$ the $\\beta_i$-dependent...

  18. The All-digital Approach to LHC Power Converter Current Control

    Dinius, A H; Pett, John G; Brazier, J C L

    2001-01-01

    The design of the LHC machine imposes severe demands upon the control of current in the 1700 magnet circuits. This has required the use of novel methods for the control of individual power converters and of the magnet current control system as a whole. This paper will review the chosen hardware and software methods and architectures. The digital regulation techniques used to achieve the overall targets for short-term stability (<3ppm) and reproducibility (<10ppm) of the 24 principal LHC circuits will be discussed. While the proposed system architecture will follow the canonical three-layer design, so successfully exploited in LEP, the software will be far from traditional. This software must be more reliable and maintainable than ever before, and will need to integrate with advanced object-oriented applications via commercial middleware. These challenges will be faced by applying object-oriented techniques throughout the system and by harnessing the power of XML for system definition.

  19. Eddy currents in the plates of the 'ATLAS' hadronic calorimeter. Semi-analytic approach

    The aim of this work is to estimate the forces, due to the eddy currents, acting on the plates of the hadronic calorimeter of the ATLAS detector in case of a quench in the superconducting solenoidal coil. Preliminary to eventual computations using general eddy currents simulation tools, which would be anyway delicate and costly, an estimation is given, made by a simple program based on analytical formulas justified by specific approximations assuming an axisymmetric geometry. The numerical method is presented, which lies on a matrix formulation, together with the encountered difficulties and the hypothesis that has been assumed in order to avoid them. The results for an 'initial configuration' and a modified one are presented. For the initial configuration the most important force acting on a plate has a value of 35000 N. For the other configuration this force is of the order of 10000 N. (K.A.). 1 ref., 8 figs

  20. Computational approach to characterize the mass transfer between the counter-current gas-liquid flow

    Xu, Y.Y.; Yuan, J.Q. [Department of Automation, Shanghai Jiaotong University, Shanghai (China); Paschke, S.; Wozny, G. [Department of Process Dynamics and Operation, TU Berlin (Germany); Repke, J.U.

    2009-08-15

    Structured packed columns are widely used in the chemical industry for distillation and absorption. However, the understanding of the transfer mechanism behind the counter-current gas-liquid flow in structured packed columns is still limited. In this work, a three-dimensional CFD model that considers the local absorption and the local momentum transfer mechanism is developed for a film flow on a small plate with a counter-current gas flow. The model, based on the volume of fluid (VOF) method, is built up on the basis of a pressure drop model and the penetration theory to quantitatively investigate the instantaneous hydrodynamics and mass transfer characteristics of the liquid phase. Simulations and experiments are carried out for a system consisting of propane and toluene. A comparison of the simulation results with the experimental data for the outlet concentrations shows good agreement. (Abstract Copyright [2009], Wiley Periodicals, Inc.)

  1. The Blood Pressure "Uncertainty Range" – a pragmatic approach to overcome current diagnostic uncertainties (II)

    Pater Cornel

    2005-01-01

    Abstract A tremendous amount of scientific evidence regarding the physiology and physiopathology of high blood pressure combined with a sophisticated therapeutic arsenal is at the disposal of the medical community to counteract the overall public health burden of hypertension. Ample evidence has also been gathered from a multitude of large-scale randomized trials indicating the beneficial effects of current treatment strategies in terms of reduced hypertension-related morbidity and mortality....

  2. Current and previous eating practices among women recovered from anorexia nervosa: a qualitative approach

    Mariana Dimitrov Ulian; Ramiro Fernandez Unsain; Priscila de Morais Sato; Patrícia da Rocha Pereira; Isis de Carvalho Stelmo; Fernanda Sabatini; Fernanda Baeza Scagliusi

    2013-01-01

    OBJECTIVE: The aim of this study was to analyze qualitatively how women, who have recovered from anorexia nervosa, perceive and describe their current eating practices, as well as the ones developed during the eating disorder period. METHODS: Seven women were interviewed individually with the objective of investigating their eating practices, transition phases and all relevant aspects that somewhat contributed to the habit-forming; experiences, feelings and perceptions related to mealtime and...

  3. Computation of general nonstationary 2D eddy currents in linear moving arrangements using integrodifferential approach

    Karban, P.; Doležel, Ivo; Šolín, Pavel

    2006-01-01

    Roč. 25, č. 3 (2006), s. 635-641. ISSN 0332-1649 R&D Projects: GA ČR(CZ) GA102/03/0047; GA ČR(CZ) GA102/05/0629 Institutional research plan: CEZ:AV0Z20570509 Keywords : eddy currents * numerical analysis * modelling Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering Impact factor: 0.274, year: 2006

  4. Numerical simulation of fracking in shale rocks : current state and future approaches.

    Hattori, G.; Trevelyan, J; Augarde, C.E.; Coombs, W.M.; Aplin, A.C.

    2016-01-01

    Extracting gas from shale rocks is one of the current engineering challenges but offers the prospect of cheap gas. Part of the development of an effective engineering solution for shale gas extraction in the future will be the availability of reliable and efficient methods of modelling the development of a fracture system, and the use of these models to guide operators in locating, drilling and pressurising wells. Numerous research papers have been dedicated to this problem, but the informati...

  5. Challenging current approaches to climate change adaptation : A study of climate change adaptation in El Salvador

    2012-01-01

    The world is on track for four degrees Celsius of global warming under current carbon emission trends, and with this the limits for human and environmental adaptation are likely to be exceeded in many parts of the world. Climate changes affect normal people in their complex everyday lives in contexts of different risks and challenges Adaptation happens in different ways in different places, resulting in different local outcomes responding to a global phenomenon. Today’s climate change adaptat...

  6. Current National Approach to Healthcare ICT Standardization: Focus on Progress in New Zealand

    Park, Young-Taek; Atalag, Koray

    2015-01-01

    Objectives Many countries try to efficiently deliver high quality healthcare services at lower and manageable costs where healthcare information and communication technologies (ICT) standardisation may play an important role. New Zealand provides a good model of healthcare ICT standardisation. The purpose of this study was to review the current healthcare ICT standardisation and progress in New Zealand. Methods This study reviewed the reports regarding the healthcare ICT standardisation in Ne...

  7. The effectiveness of current approaches to workplace stress management in the nursing profession: an evidence based literature review

    Mimura, C; Griffiths, P

    2003-01-01

    The effectiveness of current approaches to workplace stress management for nurses was assessed through a systematic review. Seven randomised controlled trials and three prospective cohort studies assessing the effectiveness of a stress management programmes were identified and reviewed. The quality of research identified was weak. There is more evidence for the effectiveness of programmes based on providing personal support than environmental management to reduce stressors. However, since the...

  8. An Approach to Model Earth Conductivity Structures with Lateral Changes for Calculating Induced Currents and Geoelectric Fields during Geomagnetic Disturbances

    Bo Dong; Zezhong Wang; Risto Pirjola; Chunming Liu; Lianguang Liu

    2015-01-01

    During geomagnetic disturbances, the telluric currents which are driven by the induced electric fields will flow in conductive Earth. An approach to model the Earth conductivity structures with lateral conductivity changes for calculating geoelectric fields is presented in this paper. Numerical results, which are obtained by the Finite Element Method (FEM) with a planar grid in two-dimensional modelling and a solid grid in three-dimensional modelling, are compared, and the flow of induced tel...

  9. The generalized BLM approach to fix scale- dependence in QCD: the current status of investigations

    Kataev, A. L.

    2015-05-01

    I present a brief review of the generalized Brodsky-Lepage-McKenzie (BLM) approaches to fix the scale-dependence of the renormalization group (RG) invariant quantities in QCD. At first, these approaches are based on the expansions of the coefficients of the perturbative series for the RG-invariant quantities in the products of the coefficients βi of the QCD β-function, which are evaluated in the MS-like schemes. As a next step all βi-dependent terms are absorbed into the BLM-type scale(s) of the powers of the QCD couplings. The difference between two existing formulations of the above mentioned generalizations based on the seBLM approach and the Principle of Maximal Conformality (PMC) are clarified in the case of the Bjorken polarized deep-inelastic scattering sum rule. Using the conformal symmetry-based relations for the non-singlet coefficient functions of the Adler D-function and of Bjorken polarized deep-inelastic scattering sum rules CBjpNS (as) the βi-dependent structure of the NNLO approximation for CBjpNS (as) is predicted in QCD with ngl-multiplet of gluino degrees of freedom, which appear in SUSY extension of QCD. The importance of performing the analytical calculation of the N3LO additional contributions of ngl gluino multiplet to CBjpNS (as) for checking the presented in the report NNLO prediction and for the studies of the possibility to determine the discussed β-expansion pattern of this sum rule at the O(a4s)-level is emphasised.

  10. Current clinical immunotherapeutic approaches for head and neck cancer [version 1; referees: 2 approved

    Carolina Soto Chervin; Bruce Brockstein

    2016-01-01

    It was estimated that 59,340 new cases of head and neck cancer would be diagnosed in the US alone in 2015 and that 12,290 deaths would be attributed to the disease. Local and regional recurrences may be treated with chemotherapy and radiation; however, metastatic head and neck cancer is fatal and is treated with chemotherapy for palliation. Recent successful treatment of a variety of solid and hematological malignancies by immunotherapeutic approaches (i.e. harnessing the body’s own immune sy...

  11. The separation of the East Australian Current: A Lagrangian approach to potential vorticity and upstream control

    Ypma, S. L.; van Sebille, E.; Kiss, A. E.; Spence, P.

    2016-01-01

    The East Australian Current (EAC) is the western boundary current flowing along the east coast of Australia separating from the coast at approximately 34°S. After the separation two main pathways can be distinguished, the eastward flowing Tasman Front and the extension of the EAC flowing southward. The area south of the separation latitude is eddy-rich and the separation latitude of the EAC is variable. Little is known of the properties of the water masses that separate at the bifurcation of the EAC. This paper presents new insights from the Lagrangian perspective, where the water masses that veer east and those that continue south are tracked in an eddy-permitting numerical model. The transport along the two pathways is computed, and a 1:3 ratio between transport in the EAC extension and transport in the Tasman Front is found. The results show that the "fate" of the particles is to first order already determined by the particle distribution within the EAC current upstream of the separation latitude, where 85% of the particles following the EAC extension originate from below 460 m and 90% of the particles following the Tasman Front originate from the top 460 m depth at 28°S. The separation and pathways are controlled by the structure of the isopycnals in this region. Analysis of anomalies in potential vorticity show that in the region where the two water masses overlap, the fate of the water depends on the presence of anticyclonic eddies that push isopycnals down and therefore enable particles to travel further south.

  12. Patient centric approach for clinical trials: Current trend and new opportunities

    Neha Shankar Sharma

    2015-01-01

    Full Text Available The clinical research industry today is undergoing a major facelift. Companies are continuously looking to adopt and implement effective and innovative ways to accelerate drug launches in the market. Companies today are more open and do not view patients as mere "subjects" who generate data, - but as informed collaborators whose participation is "core" to the overall success of trials leading to the emergence of the concept of "patient-centric trials." This paper is intended to highlight the current trends and new opportunities that can be seen in industry -indicative of crucial role patients today play in their own health care using technology, social media and self education.

  13. Current Research and Classroom Practice: Toward More Inclusive Approaches to Literacy Development in Schools

    David Booth

    2009-07-01

    Full Text Available This paper offers an exploration of current research and related practice in boys’ literacy development, interprets key findings in the literature, and further explores some of the complex dilemmas and debates related to the ‘gender gap’ – i.e., differences between the achievement of boys and girls in this area. In conclusion, the authors suggest that governments, policy-makers, administrators, teachers and parents all need to closely examine and consider available research-based strategies and classroom interventions that can effectively support both boys and girls in their literacy development. 

  14. Accounting for indirect land-use changes in GHG balances of biofuels: Review of current approaches

    Gnansounou, E.; Panichelli, L.; Dauriat, A.; Villegas, J. D.

    2008-01-01

    Increased demand for biofuels is expected to produce changes in the present land-use configuration. Furthermore there is a growing concern about the effect of land-use change on biodiversity, food supply, soil and water quality. Biofuels production on current land and use of biomass in a given region can induce displacement of activities and land-use changes elsewhere. This effect is known as indirect land-use change (ILUC). Due to changes in the carbon stock of the soil and the biomass, indi...

  15. Long-Term Control of Human Immunodeficiency Virus-1 Replication Despite Extensive Resistance to Current Antiretroviral Regimens: Clonal Analysis of Resistance Mutations in Proviral Deoxyribonucleic Acid.

    Stella-Ascariz, Natalia; Montejano, Rocio; Martin-Vicente, María; Mingorance, Jesús; Pérez-Valero, Ignacio; Bernardino, José I; Arribas, Jose R

    2016-01-01

    Archived resistance mutations compromise antiretroviral treatment. We have investigated 3 selected aviremic patients who had extensive historical resistance to their current regimen. All 3 patients underwent unstructured treatment interruptions associated to the re-emergence of wild-type virus before starting their current suppressive regimes. Almost all historical resistance mutations detected in plasma were found in circulating proviral deoxyribonucleic acid. None of the clones analyzed was fully resistant to the current antiretroviral regimen. PMID:27006965

  16. Acid gas injection: Another approach of acid gas treatment%酸气回注——酸气处理的另一途径

    John J.Carroll; Shouxi Wang; 汤林

    2009-01-01

    目前在北美,很多生产富含硫化氢和二氧化碳的天然气公司均采用一种新技术处理其废气,该废气的主要成分为硫化氢和二氧化碳,故称为"酸气".这种处理酸气的过程被称为酸气回注系统,其过程主要涉及酸气压缩、输送以及注入地下储存层.这种酸气回注技术解决了地面硫的回收和二氧化碳排放对空气污染的问题,已经逐渐成为一种切实可行的酸气处理方法.为此,针对不同回注酸气流的组成,分别从回注酸气的地层、回注酸气的管道、酸气流体相包络曲线、酸气压缩机、酸气含水量和压缩机操作过程中的注意事项等方面全面介绍了酸气回注技术及酸气回注系统的设计要点.该方法是酸气处理的另一条途经.%At present, many sour natural gas producers in North America adopt a new technology to deal with the waste gas, so-called acid gas, which mainly contains H_2S and CO_2. The acid gas treatment technology is also called acid gas injection system, the process of which involves the compression, transportation, and subsurface injection of acid gas stream. This technology has become a feasible and practical method of acid gas treatment which has solved the problems of sulfur recovery and carbon dioxide emission. According to different compositions of acid gas stream, acid gas injection design requires many sides of considerations including the underground stratum and pipes of acid flooding, the envelop curve of acid gas stream, the acid gas compressor, the water content in acid gas, and the operation process of the compressor, etc. This new technology has been proved to be another good approach of dealing with acid gas in fields.

  17. Rational approach for self-limiting current injection transformers confirmed by coupled electromagnetic-thermal FEM simulation

    Current injection transformer (CIT) systems are within the major group of the standard-type test of high current components in the electrical industry. The present precious approach contemplates an arrangement for a rational design of a self-current limiting transformer (SLT) being integrated by a single unit 25 kA CIT system for fast overcurrent detection in stipulated current tests. This paper describes mathematical formulations based on an electric models and the dominant effects of an auxiliary winding on the rate of the self-limiting process of the system. This requires the evaluation of multiphysical (i.e. coupling of the electromagnetic and thermal parts) finite element modelling and simulations for three different approaches to suit the designer's choice. An overcurrent causes a considerable distortion of axial leakage flux, which in turn produces high radial forces. The transient analysis of the leakage flux densities and the corresponding electromagnetic forces on windings of the CIT and proposed SLT are the other objects of this paper. Moreover, the distribution of the flux density and the corresponding localized losses within the SLT core are further objects of this paper. However, this paper will mark another important event in superconductor technology and augment efficiency and compactness from which a lower overall cost of the CIT system could be attainable.

  18. Applying quantitative structure–activity relationship approaches to nanotoxicology: Current status and future potential

    The potential (eco)toxicological hazard posed by engineered nanoparticles is a major scientific and societal concern since several industrial sectors (e.g. electronics, biomedicine, and cosmetics) are exploiting the innovative properties of nanostructures resulting in their large-scale production. Many consumer products contain nanomaterials and, given their complex life-cycle, it is essential to anticipate their (eco)toxicological properties in a fast and inexpensive way in order to mitigate adverse effects on human health and the environment. In this context, the application of the structure–toxicity paradigm to nanomaterials represents a promising approach. Indeed, according to this paradigm, it is possible to predict toxicological effects induced by chemicals on the basis of their structural similarity with chemicals for which toxicological endpoints have been previously measured. These structure–toxicity relationships can be quantitative or qualitative in nature and they can predict toxicological effects directly from the physicochemical properties of the entities (e.g. nanoparticles) of interest. Therefore, this approach can aid in prioritizing resources in toxicological investigations while reducing the ethical and monetary costs that are related to animal testing. The purpose of this review is to provide a summary of recent key advances in the field of QSAR modelling of nanomaterial toxicity, to identify the major gaps in research required to accelerate the use of quantitative structure–activity relationship (QSAR) methods, and to provide a roadmap for future research needed to achieve QSAR models useful for regulatory purposes

  19. Applying quantitative structure-activity relationship approaches to nanotoxicology: current status and future potential.

    Winkler, David A; Mombelli, Enrico; Pietroiusti, Antonio; Tran, Lang; Worth, Andrew; Fadeel, Bengt; McCall, Maxine J

    2013-11-01

    The potential (eco)toxicological hazard posed by engineered nanoparticles is a major scientific and societal concern since several industrial sectors (e.g. electronics, biomedicine, and cosmetics) are exploiting the innovative properties of nanostructures resulting in their large-scale production. Many consumer products contain nanomaterials and, given their complex life-cycle, it is essential to anticipate their (eco)toxicological properties in a fast and inexpensive way in order to mitigate adverse effects on human health and the environment. In this context, the application of the structure-toxicity paradigm to nanomaterials represents a promising approach. Indeed, according to this paradigm, it is possible to predict toxicological effects induced by chemicals on the basis of their structural similarity with chemicals for which toxicological endpoints have been previously measured. These structure-toxicity relationships can be quantitative or qualitative in nature and they can predict toxicological effects directly from the physicochemical properties of the entities (e.g. nanoparticles) of interest. Therefore, this approach can aid in prioritizing resources in toxicological investigations while reducing the ethical and monetary costs that are related to animal testing. The purpose of this review is to provide a summary of recent key advances in the field of QSAR modelling of nanomaterial toxicity, to identify the major gaps in research required to accelerate the use of quantitative structure-activity relationship (QSAR) methods, and to provide a roadmap for future research needed to achieve QSAR models useful for regulatory purposes. PMID:23165187

  20. A Green Approach to the Production of Hybrid Diindolylmethane-Phenylboronic Acids via a 3MCR: Promising Antineoplasic Molecules

    Mónica Zarco Juarez

    2013-01-01

    Full Text Available The current role of the “Green Chemistry Protocol” in multicomponent reactions is first highlighted. Then, the green approach to the production of three novel hybrid diindolylmethanes-phenylboronic acids via a 3MCR is discussed, which features the following: solventless conditions, the use of microwave irradiation to activate the reactions, the absence of catalyst, and an efficient atom economy. The products were achieved with moderate yields (41–61% within a short time frame (5 min and appropriately characterized by elemental analysis and spectroscopic methods (NMR: 1H, 13C, 11B; MS: EI, CI, FAB+, HRMS. During the FAB+ MS determinations, various artifacts that are associated with the boron atom via an interaction with thioglycerol from the matrix were noted in the corresponding FAB+ mass spectra; in addition, the accurate mass determination of these adducts unequivocally confirmed the presence of the target molecules. Moreover, the activity of these target molecules was evaluated in the presence of six cancer cell lines (U251 = glia of the central nerve system, PC-3 = prostate, K562 = leukemia, HCT-15 = colon, MCF-7 = breast, and SKLU-1 = lung, which resulted in the meta-regioisomer being the most active. Finally, the products were also analyzed using computational chemistry in order to determine their most stable geometries and reactivities by computing the respective molecular electrostatic potentials.

  1. Scattering approach to frequency-dependent current noise in Fabry-Pérot graphene devices

    Hammer, Jan; Belzig, Wolfgang

    2013-03-01

    We study finite-frequency quantum noise and photon-assisted electron transport through a wide and ballistic graphene sheet between two metallic leads. The elementary excitations allow us to examine the differences between effects related to Fabry-Pérot-like interferences and signatures caused by correlations of coherently scattered particles in electron- and holelike parts of the Dirac spectrum. We identify different features in the current-current auto- and cross-correlation spectra and trace them back to the interference patterns of the product of transmission and reflection amplitudes, which define the integrands of the involved correlators. At positive frequencies, the correlator of the autoterminal noise spectrum with final and initial states associated to the measurement terminal is dominant. Phase jumps occur within the interference patterns of corresponding integrands, which also reveal the intrinsic energy scale of the two-terminal graphene setup. The excess noise spectra, as well as the cross-correlation ones, show large fluctuations between positive and negative values. Oscillatory signatures of the cross-correlation noise are due to an alternating behavior of the integrands.

  2. About nucleon-nucleon potential: meson exchange currents and relativistic approach of nuclear structure

    Various aspects of nuclear physics at intermediate energies, in connection with the description of the nucleon-nucleon potential in terms of mesons, are presented in this thesis. The meson exchange current contribution is studied in the case of the deuteron (np capture and electrodisintegration near threshold). A consistent description of these processes is discussed, with particular emphasis on the effective range of the current, for momentum transfers as large as q2∼1 (GeV/c)2. The structure of finite nuclei and nuclear matter is then analysed in the framework of a relativistic formalism, in which the negative energy component of the nucleon wave function is explicitly taken into account. The nuclear matter saturation mechanism is studied in details and compared with the non-relativistic limit. Properties of finite nuclei are also discussed. Finally, the structure of the nucleon itself in the nuclear medium is investigated. A connection between the polarisation of the nucleon (three valence quark component), the incompressibility parameter and the mass of the first monopole excitation of the nucleon is presented

  3. INFLUENCE OF ACID CONCENTRATION, TEMPERATURE, AND TIME ON THE CONCENTRATED SULFURIC ACID HYDROLYSIS OF PINEWOOD AND ASPENWOOD: A STATISTICAL APPROACH

    Kando K. Janga

    2011-11-01

    Full Text Available The effects on sugar yields of acid concentration, temperature, and time in the first (decrystallization stage of a two-stage concentrated sulfuric acid hydrolysis of softwood (Scots pine and hardwood (aspen were investigated. The study focused on the multi-variable effects of the decrystallization stage and applied a statistical modeling with Central Composite Face (CCF design of experiment to systematically study and simulate the effect of decrystallization reaction conditions on hydrolysis products and degradation products. The models were statistically significant and showed that for both aspen and pine, the reaction temperature and acid concentration were the most influential variables on monosaccharides and total sugar yields compared to the reaction time. The interaction between temperature and acid concentration was the most important for both species. The sugar degradation products were much influenced by the decrystallization temperature on both aspen and pine. The models were validated by a test-set and showed a good agreement between the experimental and predicted values. The optimum predicted total sugar yields were 56 g / 100 g d.w for aspen (74% theoretical and 64 g / 100 g d.w for pine (91% theoretical.

  4. A multi-instrument approach to monitoring turbidity currents: Case study from the Squamish Delta, British Columbia (Canada)

    Hage, Sophie; Cartigny, Matthieu; Clare, Michael; Talling, Peter; Sumner, Esther; Vardy, Mark; Hughes Clarke, John

    2016-04-01

    Turbidity currents are volumetrically the most important process for moving sediment in submarine environments. They may travel at high speeds, thereby posing a threat to important and expensive seafloor infrastructure. Despite their importance, we still know little about their flow dynamics because direct monitoring is challenging and consequently rare. Additionally, the few settings in which monitoring has been feasible, have generally involved a single instrument approach, either measuring flow velocity, sediment concentration or grain size. Here we present results issued from a multi-instrument study where a single turbidity current was observed with several instruments at the same location and time using different measuring frequencies. Three types of geophysical sensors were deployed from a single vessel moored over a turbidity current channel on the Squamish Delta in British Colombia, Canada. First, two 500 kHz multibeam sonars suspended from the bow of the ship imaged the incoming turbidity current and documented its interaction with the crescentic bedforms on the channel thalweg. Second, a 600 kHz downward-looking Acoustic Doppler Current Profiler (ADCP) lowered from the back of the ship provided vertical profiles of velocity through time. Third, a 1.0-24.0 kHz Chirp profiler enabled for the first time imaging of the dense near-bed zone of the turbidity current, which has so far been largely impenetrable using higher frequency sonar and ADCP instruments. Besides the stationary deployment, a repetitive multibeam survey was also performed using a moving vessel in order monitor temporal evolution of the seafloor morphology resulting from turbidity currents. By combining the measurements from each system, a single turbidity current was characterised in unusually high resolution. This current was 6 to 8 meters thick and at least 40 meters wide according to the multibeam sonars. The ADCP measured a front speed of around 1.5 m/s, higher than the internal

  5. Surpassing the current limitations of biohydrogen production systems: The case for a novel hybrid approach.

    Boboescu, Iulian Zoltan; Gherman, Vasile Daniel; Lakatos, Gergely; Pap, Bernadett; Bíró, Tibor; Maróti, Gergely

    2016-03-01

    The steadily increase of global energy requirements has brought about a general agreement on the need for novel renewable and environmentally friendly energy sources and carriers. Among the alternatives to a fossil fuel-based economy, hydrogen gas is considered a game-changer. Certain methods of hydrogen production can utilize various low-priced industrial and agricultural wastes as substrate, thus coupling organic waste treatment with renewable energy generation. Among these approaches, different biological strategies have been investigated and successfully implemented in laboratory-scale systems. Although promising, several key aspects need further investigation in order to push these technologies towards large-scale industrial implementation. Some of the major scientific and technical bottlenecks will be discussed, along with possible solutions, including a thorough exploration of novel research combining microbial dark fermentation and algal photoheterotrophic degradation systems, integrated with wastewater treatment and metabolic by-products usage. PMID:26790867

  6. Current approaches in the management of low risk Hodgkin lymphoma in children and adolescents.

    Giulino-Roth, Lisa; Keller, Frank G; Hodgson, David C; Kelly, Kara M

    2015-06-01

    The outcome for children and adolescents with low risk Hodgkin lymphoma (HL) is excellent, with event-free survival >85% and overall survival >95%. Historically, however, treatment has come at the cost of significant long-term toxicity from chemotherapy, radiation or a combination of these. Recent treatment strategies have focused on maintaining high event-free and overall survival while minimizing the use of therapy associated with late effects. The strategies used to achieve this vary greatly among paediatric cooperative groups and there is no one standard treatment for children with low risk HL. This review summaries recent clinical trials in paediatric low risk HL and addresses some of the important considerations when comparing trials, including differences in the definition of low risk HL, differences in outcome among histological subtypes and varying approaches to reduce or eliminate radiation therapy. Recommendations are provided for the treatment of children with low risk HL outside the setting of a clinical trial. PMID:25824371

  7. Conducting Economic Evaluations Alongside Randomised Trials: Current Methodological Issues and Novel Approaches.

    Hughes, Dyfrig; Charles, Joanna; Dawoud, Dalia; Edwards, Rhiannon Tudor; Holmes, Emily; Jones, Carys; Parham, Paul; Plumpton, Catrin; Ridyard, Colin; Lloyd-Williams, Huw; Wood, Eifiona; Yeo, Seow Tien

    2016-05-01

    Trial-based economic evaluations are an important aspect of health technology assessment. The availability of patient-level data coupled with unbiased estimates of clinical outcomes means that randomised controlled trials are effective vehicles for the generation of economic data. However there are methodological challenges to trial-based evaluations, including the collection of reliable data on resource use and cost, choice of health outcome measure, calculating minimally important differences, dealing with missing data, extrapolating outcomes and costs over time and the analysis of multinational trials. This review focuses on the state of the art of selective elements regarding the design, conduct, analysis and reporting of trial-based economic evaluations. The limitations of existing approaches are detailed and novel methods introduced. The review is internationally relevant but with a focus towards practice in the UK. PMID:26753558

  8. Vulvar cancer: initial management and systematic review of literature on currently applied treatment approaches.

    Sznurkowski, Jacek Jan

    2016-07-01

    This review provides guidelines and aims to estimate utilisation rates of treatment modalities applied in vulvar cancer. Current standards of treatment are as follows: wide local excision instead of radical vulvectomy in the case of small tumour (T cancer', 'treatment' identified seven full-text manuscripts, including data on 1114 patients. Utilisation rates of neoadjuvant radiochemotherapy, chemotherapy alone, surgery, adjuvant radiotherapy and adjuvant radiochemotherapy were 5.9%, 0.3%, 89.3%, 22.6% and 0.2% respectively. An evidence-based estimation of appropriate rates of surgery, radiotherapy and chemotherapy for vulvar cancer is needed to compare management reflecting guidelines with presented here real frequency of applied modalities. PMID:26880231

  9. Characterisation of plastic packaging waste for recycling: problems related to current approaches

    Götze, Ramona; Astrup, Thomas Fruergaard

    2013-01-01

    criteria of recycling processes. A lack of information in current waste characterisation practise on polymer resin composition, black coloured material content and the influence of surface adherent material on physico-chemical characteristics of plastic packaging waste were identified. These shortcomings......Informed decisions regarding new recycling schemes require waste characterisation studies which provide in addition to data on waste amounts and the share of recyclable fractions, accurate data on physico-chemical characteristics of the waste materials considering the material specific input...... were addressed by a resin type-based sorting analysis and a washing test for plastic packaging material from Danish household waste. Preliminary results show that, for a quarter of the hand sorted material, no resin type could be identified and that Polypropylene and Polyethylene terephthalate were the...

  10. Current approaches for assessing insulin sensitivity and resistance in vivo: advantages, limitations, and appropriate usage.

    Muniyappa, Ranganath; Lee, Sihoon; Chen, Hui; Quon, Michael J

    2008-01-01

    Insulin resistance contributes to the pathophysiology of diabetes and is a hallmark of obesity, metabolic syndrome, and many cardiovascular diseases. Therefore, quantifying insulin sensitivity/resistance in humans and animal models is of great importance for epidemiological studies, clinical and basic science investigations, and eventual use in clinical practice. Direct and indirect methods of varying complexity are currently employed for these purposes. Some methods rely on steady-state analysis of glucose and insulin, whereas others rely on dynamic testing. Each of these methods has distinct advantages and limitations. Thus, optimal choice and employment of a specific method depends on the nature of the studies being performed. Established direct methods for measuring insulin sensitivity in vivo are relatively complex. The hyperinsulinemic euglycemic glucose clamp and the insulin suppression test directly assess insulin-mediated glucose utilization under steady-state conditions that are both labor and time intensive. A slightly less complex indirect method relies on minimal model analysis of a frequently sampled intravenous glucose tolerance test. Finally, simple surrogate indexes for insulin sensitivity/resistance are available (e.g., QUICKI, HOMA, 1/insulin, Matusda index) that are derived from blood insulin and glucose concentrations under fasting conditions (steady state) or after an oral glucose load (dynamic). In particular, the quantitative insulin sensitivity check index (QUICKI) has been validated extensively against the reference standard glucose clamp method. QUICKI is a simple, robust, accurate, reproducible method that appropriately predicts changes in insulin sensitivity after therapeutic interventions as well as the onset of diabetes. In this Frontiers article, we highlight merits, limitations, and appropriate use of current in vivo measures of insulin sensitivity/resistance. PMID:17957034

  11. Advantages of the non-stationary approach: test on eddy current signals

    Conventional signal processing is often unsuitable for the interpretation of intrinsically non-stationary signals, such as surveillance or non destructive testing signals. In these cases, ''advanced'' methods are required. This report presents two applications of non-stationary signal processing methods to the complex signals obtained in eddy current non destructive testing of steam generator tubes. The first application consists in segmenting the absolute channel, which can be likened to a piecewise constant signal. The Page-Hinkley cumulative sum algorithm is used, enabling detection of unknown mean amplitude jumps in a piecewise constant signal disturbed by a white noise. Results are comparable to those obtained with the empirical method currently in use. As easy to implement as the latter, the Page-Hinkley algorithm has the added advantage of being well formalized and of identifying whether the jumps in mean are positive or negative. The second application concerns assistance in detecting characteristic fault transients in the differential channels, using the continuous wavelet transform. The useful signal and noise spectra are fairly close, but not strictly identical. With the continuous wavelet transform, these frequency differences can be turned to account. The method was tested on synthetic signals obtained by summing noise and real defect signals. Using the continuous wavelet transform reduces the minimum signal-to-noise ratio by 5 dB for detection of a transient as compared with direct detection on the original signal. Finally, a summary of non-stationary methods using our data is presented. The two investigations described confirm that non-stationary methods may be considered as interesting signal and image analysis tools, as an efficient complement to conventional methods. (author). 24 figs., 13 refs

  12. Pharmacological approaches to improving cognitive function in Down syndrome: current status and considerations

    Gardiner KJ

    2014-12-01

    Full Text Available Katheleen J Gardiner Linda Crnic Institute for Down Syndrome, Department of Pediatrics, Department of Biochemistry and Molecular Genetics, Human Medical Genetics and Genomics Program, Neuroscience Program, University of Colorado School of Medicine, Aurora, CO, USA Abstract: Down syndrome (DS, also known as trisomy 21, is the most common genetic cause of intellectual disability (ID. Although ID can be mild, the average intelligence quotient is in the range of 40–50. All individuals with DS will also develop the neuropathology of Alzheimer’s disease (AD by the age of 30–40 years, and approximately half will display an AD-like dementia by the age of 60 years. DS is caused by an extra copy of the long arm of human chromosome 21 (Hsa21 and the consequent elevated levels of expression, due to dosage, of trisomic genes. Despite a worldwide incidence of one in 700–1,000 live births, there are currently no pharmacological treatments available for ID or AD in DS. However, over the last several years, very promising results have been obtained with a mouse model of DS, the Ts65Dn. A diverse array of drugs has been shown to rescue, or partially rescue, DS-relevant deficits in learning and memory and abnormalities in cellular and electrophysiological features seen in the Ts65Dn. These results suggest that some level of amelioration or prevention of cognitive deficits in people with DS may be possible. Here, we review information from the preclinical evaluations in the Ts65Dn, how drugs were selected, how efficacy was judged, and how outcomes differ, or not, among studies. We also summarize the current state of human clinical trials for ID and AD in DS. Lastly, we describe the genetic limitations of the Ts65Dn as a model of DS, and in the preclinical testing of pharmacotherapeutics, and suggest additional targets to be considered for potential pharmacotherapies. Keywords: Ts65Dn, pharmacotherapy, clinical trials, Hsa21

  13. IMRT dose fractionation for head and neck cancer: Variation in current approaches will make standardisation difficult

    Ho, Kean F. (Academic Dept. of Radiation Oncology, Univ. of Manchester, Manchester (United Kingdom)); Fowler, Jack F. (Dept. of Human Oncology and Medical Physics, Univ. of Wisconsin, Wisconsin (United States)); Sykes, Andrew J.; Yap, Beng K.; Lee, Lip W.; Slevin, Nick J. (Dept. of Clinical Oncology, Christie Hospital NHS Foundation Trust, Manchester (United Kingdom))

    2009-04-15

    Introduction. Altered fractionation has demonstrated clinical benefits compared to the conventional 2 Gy/day standard of 70 Gy. When using synchronous chemotherapy, there is uncertainty about optimum fractionation. IMRT with its potential for Simultaneous Integrated Boost (SIB) adds further to this uncertainty. This survey will examine international practice of IMRT fractionation and suggest possible reasons for diversity in approach. Material and methods. Fourteen international cancer centres were surveyed for IMRT dose/fractionation practised in each centre. Results. Twelve different types of dose fractionation were reported. Conventional 70-72 Gy (daily 2 Gy/fraction) was used in 3/14 centres with concurrent chemotherapy while 11/14 centres used altered fractionation. Two centres used >1 schedule. Reported schedules and number of centres included 6 fractions/week DAHANCA regime (3), modest hypofractionation (=2.2 Gy/fraction) (3), dose-escalated hypofractionation (=2.3 Gy/fraction) (4), hyperfractionation (1), continuous acceleration (1) and concomitant boost (1). Reasons for dose fractionation variability include (i) dose escalation; (ii) total irradiated volume; (iii) number of target volumes; (iv) synchronous systemic treatment; (v) shorter overall treatment time; (vi) resources availability; (vii) longer time on treatment couch; (viii) variable GTV margins; (ix) confidence in treatment setup; (x) late tissue toxicity and (xi) use of lower neck anterior fields. Conclusions. This variability in IMRT fractionation makes any meaningful comparison of treatment results difficult. Some standardization is needed particularly for design of multi-centre randomized clinical trials.

  14. IMRT dose fractionation for head and neck cancer: Variation in current approaches will make standardisation difficult

    Introduction. Altered fractionation has demonstrated clinical benefits compared to the conventional 2 Gy/day standard of 70 Gy. When using synchronous chemotherapy, there is uncertainty about optimum fractionation. IMRT with its potential for Simultaneous Integrated Boost (SIB) adds further to this uncertainty. This survey will examine international practice of IMRT fractionation and suggest possible reasons for diversity in approach. Material and methods. Fourteen international cancer centres were surveyed for IMRT dose/fractionation practised in each centre. Results. Twelve different types of dose fractionation were reported. Conventional 70-72 Gy (daily 2 Gy/fraction) was used in 3/14 centres with concurrent chemotherapy while 11/14 centres used altered fractionation. Two centres used >1 schedule. Reported schedules and number of centres included 6 fractions/week DAHANCA regime (3), modest hypofractionation (=2.2 Gy/fraction) (3), dose-escalated hypofractionation (=2.3 Gy/fraction) (4), hyperfractionation (1), continuous acceleration (1) and concomitant boost (1). Reasons for dose fractionation variability include (i) dose escalation; (ii) total irradiated volume; (iii) number of target volumes; (iv) synchronous systemic treatment; (v) shorter overall treatment time; (vi) resources availability; (vii) longer time on treatment couch; (viii) variable GTV margins; (ix) confidence in treatment setup; (x) late tissue toxicity and (xi) use of lower neck anterior fields. Conclusions. This variability in IMRT fractionation makes any meaningful comparison of treatment results difficult. Some standardization is needed particularly for design of multi-centre randomized clinical trials

  15. Approaches of Taxation under the Current Circumstances between Desiderata and Results – I

    Georgeta Dragomir

    2011-02-01

    Full Text Available As a basic component of modern society, the taxation should combine the main objectivefor the public authority, to ensure most of the resources necessary to carry out state functions, withtargets at least as important on the country's economic development, supporting social issues,respecting the law and the financial discipline, in terms of efficiency, stability and sustainability. Forthese reasons, the level of taxation is very important for the present and future developments of acountry and the relevance of the analysis in this direction exceeds the economic, social or politicallevel. They practice different ways to understand and determine the impact of taxation in an economyand their uniform and realistic approach is important in order to succeed effective internationalcomparability and responsible actions at all levels, now and in the future. The public policy must findsolutions that can be adapted and implemented following the response that it gives the result ofanalysis that has as its starting point the economy, stimulating the private interest, which may leadimplicitly to obtaining parameters of superior quality at general level.

  16. Pros and cons of current approaches for detecting peroxynitrite and their applications

    Xingmiao Chen

    2014-03-01

    Full Text Available Peroxynitrite, a representative of reactive nitrogen species, plays important roles in the physiological and pathological processes of many oxidative stress-related diseases. It is generated from the reaction of nitric oxide (NO and superoxide (O2·– and is far more active than its precursors. Peroxynitrite can be further decomposed into other cytotoxic reactive species. Peroxynitrite and its derivatives can interact with various biomolecules such as DNA and proteins. Due to its high reactivity and short lifetime, accurate detection of peroxynitrite in biological systems is a challenge task. In the last decade, huge efforts have been made to develop reliable techniques to assess the generation of peroxynitrite in various cellular and animal experiments. There are three major approaches for peroxynitrite detection, including electrochemical sensors, detection of nitrotyrosine formation, and fluorescent probes. Particularly, progress has been made in developing novel fluorescent probes to detect peroxynitrite with relatively high sensitivity and specificity. Herein, we review the recent progress made in peroxynitrite detection methods and discuss the advantages and disadvantages of these methods. The development of these techniques will offer new opportunities for understanding the roles of peroxynitrite in the oxidative stress-related physiological and pathological conditions and provide platforms for drug discovery targeting peroxynitrite and other free radicals for therapeutic purposes.

  17. Approaches to LLW disposal site selection and current progress of host states

    In accordance with the Low-Level Radioactive Waste Policy Amendments Act of 1985 and under the guidance of 10 CFR 61, States have begun entering into compacts to establish and operate regional disposal facilities for low-level radioactive waste. The progress a state makes in implementing a process to identify a specific location for a disposal site is one indication of the level of a state's commitment to meeting its responsibilities under Federal law and interstate compact agreements. During the past few years, several States have been engaged in site selection processes. The purpose of this report is to summarize the site selection approaches of some of the Host States (California, Michigan, Nebraska, New York, North Carolina, Texas, and Illinois), and their progress to date. An additional purpose of the report is to discern whether the Host States's site selection processes were heavily influenced by any common factors. One factor each state held in common was that political and public processes exerted a powerful influence on the site selection process at virtually every stage. 1 ref

  18. Therapeutic Approach in the Improvement of Endothelial Dysfunction: The Current State of the Art

    Miroslav Radenković

    2013-01-01

    Full Text Available The endothelium has a central role in the regulation of blood flow through continuous modulation of vascular tone. This is primarily accomplished by balanced release of endothelial relaxing and contractile factors. The healthy endothelial cells are essential for maintenance of vascular homeostasis involving antioxidant, anti-inflammatory, pro-fibrinolytic, anti-adhesive, or anticoagulant effects. Oppositely, endothelial dysfunction is primarily characterized by impaired regulation of vascular tone as a result of reduced endothelial nitric oxide (NO synthase activity, lack of cofactors for NO synthesis, attenuated NO release, or increased NO degradation. So far, the pharmacological approach in improving/reversal of endothelial dysfunction was shown to be beneficial in clinical trials that have investigated actions of different cardiovascular drugs. The aim of this paper was to summarize some of the latest clinical findings related to therapeutic possibilities for improving endothelial dysfunction in different pathological conditions. In the majority of presented clinical investigations, the assessment of improvement or reversal of endothelial dysfunction was performed through the flow-mediated dilatation measurement, and in some of those endothelial progenitor cells’ count was used for the same purpose. Still, given the fast and continuous development of this field, the evidence acquisition included the MEDLINE data base screening and the selection of articles published between 2010 and 2012.

  19. The Multidisciplinary Approach to Renal Denervation: Current Evidences and Open Questions

    Sara Samoni

    2014-07-01

    Full Text Available Renal denervation (RD is a new clinical procedure which aims to treat resistant hypertensive patients. As with every new technology introduced into the clinical setting, many aspects were not explored sufficiently in order to be implemented into routine clinical practice. Advances in clinical technology require different steps of development, which start from preliminary in vitro experiments and finally arrive in the market, available for physicians when they have been proven to produce benefits for patients. Each stage usually takes many years before acquiring consensus from specialists involved in specific fields. In our opinion, this is a long and blind way and is a disadvantage to patients who need rapid, specific, and effective treatments. Otherwise, a multidisciplinary approach can provide the right evaluation of RD position and its potential for clinical application and research development. Therefore, we decided to draw a well-structured literature review from different specialists’ points of view in order to cover the subject in a translational manner. We reported animal models and experimental trials, in chronological order, and their evidences which have created the basis for human research. Technologies and devices were compared to underlined advantages and disadvantages. An update of clinical data was considered to define clinical needs in order to build focused trials. Furthermore, we evaluate the feasibility of routine RD clinical use by means of an economic analysis. Finally, we tried to settle the main unresolved questions and then assessed future RD perspectives, including non-hypertension indications.

  20. Vascularized composite allotransplantation: current standards and novel approaches to prevent acute rejection and chronic allograft deterioration.

    Kueckelhaus, Maximilian; Fischer, Sebastian; Seyda, Midas; Bueno, Ericka M; Aycart, Mario A; Alhefzi, Muayyad; ElKhal, Abdallah; Pomahac, Bohdan; Tullius, Stefan G

    2016-06-01

    The advent of more potent immunosuppressants led to the first successful human upper extremity transplantation in 1998. At this time, >100 upper extremity transplants, 30 face transplants, and a variety of other vascularized composite allotransplantation (VCA) procedures have been performed around the world. VCA recipients present unique challenges for transplantation. The incidence of acute rejection exceeds 80% in hand and face transplantation and is well documented, whereas reports about antibody-mediated rejection and chronic rejection remain scarce. Immunosuppression protocols commonly used at US centers are derived from solid organ transplantation protocols. Novel approaches to minimize rejections in VCA may include improved HLA matching and considerations toward cytomegalovirus infection status. New graft preservation techniques may decrease immunogenicity prior to transplant. Novel monitoring methods such as valid biomarkers, ultrasound biomicroscopy, and sentinel flaps may enable earlier diagnosis of rejection. Cell-based therapies are being explored to achieve immunosuppressive regimen minimization or even tolerance induction. The efficacy of local immunosuppression in clinical VCA remains controversial. In conclusion, although immunosuppressive strategies adapted from SOT have demonstrated good midterm results, focusing on the unique features of VCA grafts may enable additional, more specific treatment strategies in the future and improved long-term graft outcomes. PMID:26265179

  1. Approaches to LLW disposal site selection and current progress of host states

    Walsh, J.J.; Kerr, T.A.

    1990-11-01

    In accordance with the Low-Level Radioactive Waste Policy Amendments Act of 1985 and under the guidance of 10 CFR 61, States have begun entering into compacts to establish and operate regional disposal facilities for low-level radioactive waste. The progress a state makes in implementing a process to identify a specific location for a disposal site is one indication of the level of a state's commitment to meeting its responsibilities under Federal law and interstate compact agreements. During the past few years, several States have been engaged in site selection processes. The purpose of this report is to summarize the site selection approaches of some of the Host States (California, Michigan, Nebraska, New York, North Carolina, Texas, and Illinois), and their progress to date. An additional purpose of the report is to discern whether the Host States's site selection processes were heavily influenced by any common factors. One factor each state held in common was that political and public processes exerted a powerful influence on the site selection process at virtually every stage. 1 ref.

  2. Current and previous eating practices among women recovered from anorexia nervosa: a qualitative approach

    Mariana Dimitrov Ulian

    2013-12-01

    Full Text Available OBJECTIVE: The aim of this study was to analyze qualitatively how women, who have recovered from anorexia nervosa, perceive and describe their current eating practices, as well as the ones developed during the eating disorder period. METHODS: Seven women were interviewed individually with the objective of investigating their eating practices, transition phases and all relevant aspects that somewhat contributed to the habit-forming; experiences, feelings and perceptions related to mealtime and the influence that food has had over the present subjects' life. The interviews were analyzed by the discourse of the collective subject method. RESULTS: The results brought up the following topics: a control; b concerns and feelings; c deprivation d beauty dictatorship; e eating competence; f importance of food; g food cacophony. CONCLUSIONS: What stands out is a multiplicity of eating practices, which during the eating disorder were similar to and characterized by restriction; however, after recovery, part of the subjects seem to have developed a higher eating competence, whereas others show a practice similar to the one acquired during the anorexia nervosa, such as the difficulty in realizing when they are satisfied and a feeling of discomfort when facing social interactions.

  3. A Review of Current Neuromorphic Approaches for Vision, Auditory, and Olfactory Sensors.

    Vanarse, Anup; Osseiran, Adam; Rassau, Alexander

    2016-01-01

    Conventional vision, auditory, and olfactory sensors generate large volumes of redundant data and as a result tend to consume excessive power. To address these shortcomings, neuromorphic sensors have been developed. These sensors mimic the neuro-biological architecture of sensory organs using aVLSI (analog Very Large Scale Integration) and generate asynchronous spiking output that represents sensing information in ways that are similar to neural signals. This allows for much lower power consumption due to an ability to extract useful sensory information from sparse captured data. The foundation for research in neuromorphic sensors was laid more than two decades ago, but recent developments in understanding of biological sensing and advanced electronics, have stimulated research on sophisticated neuromorphic sensors that provide numerous advantages over conventional sensors. In this paper, we review the current state-of-the-art in neuromorphic implementation of vision, auditory, and olfactory sensors and identify key contributions across these fields. Bringing together these key contributions we suggest a future research direction for further development of the neuromorphic sensing field. PMID:27065784

  4. No Added Mortality Benefit From Current Approaches to Renal Replacement Therapy in ICU Patients

    Helmut Schiffl

    2014-07-01

    Full Text Available Hospital-acquired acute kidney injury (AKI, a common and harmful renal disorder, is an independent risk factor for short-term and long-term mortality particularly in critically ill patients. The management of this patient subpopulation remains supportive, with renal replacement therapy (RRT indicated in severe renal failure. RRT prevents immediate death from lethal complications of advanced AKI, and – undoubtedly – reduces the mortality in AKI patients. The field of RRT has undergone remarkable changes to further improve the dismal short-term outcome. However, trials have failed to demonstrate an additional survival benefit of choice of modality or increased dose, or timing of RRT initiation if RRT is adequately performed. Clearly, AKI is not an isolated event but results in multiple negative effects on inflammation or coagulation and in multiple organ dysfunction. The underlying mechanisms are not amenable to current RRT. Thus, we should be realistic in our expectations of what dialysis and haemofiltration could accomplish; they are not renal replacement therapies in the true sense of the word, but only supportive systems. Prevention of AKI by better care, earlier anticipation of AKI by use of novel biomarkers and pharmacologic therapy of emergent AKI, and the introduction of bioreactor systems into clinical treatment of AKI may be future strategies to further improve the poor outcome of these patients.

  5. Mite Pests in Plant Crops – Current Issues, Inovative Approaches and Possibilities for Controlling Them (1

    Radmila Petanović

    2010-01-01

    Full Text Available In the middle of the last century, mites moved into the focus of attention as pests relevantto agriculture, forestry and landscape horticulture, presumably in direct reactionto the “green revolution” that involved plant cultivation in large-plot monocropping systems,improved methods of cultivation, selection of high-yielding cultivars and intensifieduse of pesticides and mineral fertilizers. Agroecosystems in which phytophagous miteshave become harmful organisms are primarily orchards, vineyards, greenhouses, urbangreeneries, plant nurseries and stored plant products, as well as annual field crops to asomewhat lesser degree. Phytophagous mite species belong to a variety of spider mites(Tetranychidae, false spider mites (Tenuipalpidae, gall and rust mites (Eriophyoidae, tarsonemidmites (Tarsonemidae and acarid mites (Acaridae. Most of these harmful speciesare widespread, some of them having more economic impact than others and being moredetrimental as depending on various specificities of each outdoor agroecosystem in anyparticular climatic region.The first segment of this overview focuses on the most significant mite pests ofagroecosystemsand urban horticultural areas in European countries, our own region andin Serbia today, primarily on species that have caused problems in recent years regardingplant production, and it also discusses various molecular methods available for investigatingdifferent aspects of the biology of phytophagous mites. Also, acaricides are discussedas a method of controlling mite pests in the light of the current situation and trends on pesticidemarkets in Serbia and the European Union member-countries

  6. A Novel Approach in Cinnamic Acid Synthesis: Direct Synthesis of Cinnamic Acids from Aromatic Aldehydes and Aliphatic Carboxylic Acids in the Presence of Boron Tribromide

    M. Onciu

    2005-02-01

    Full Text Available Cinnamic acids have been prepared in moderate to high yields by a new direct synthesis using aromatic aldehydes and aliphatic carboxylic acids, in the presence of boron tribromide as reagent, 4-dimethylaminopyridine (4-DMAP and pyridine (Py as bases and N-methyl-2-pyrolidinone (NMP as solvent, at reflux (180-190°C for 8-12 hours.

  7. Renal response to acute acid loading--an organ physiological approach

    Osther, P J; Engel, K; Kildeberg, P

    2004-01-01

    OBJECTIVE: In previous studies of the renal response to acute NH4Cl acidosis no correlation was found between systemic acid-base status and the traditionally used quantity, renal net acid excretion (NAE). If NAE is to be considered a physiologically meaningful quantity then this is surprising, as......-base metabolism during acid loading than previously described methods....

  8. [Practical approach to complex acid-base disorders using a slide rule].

    Rives, E; Grimaud, D

    1986-01-01

    Diagnosis of mixed acid-base disturbances is often difficult. Nowadays it depends on biochemical and statistical interpretation, coupled with clinical data. The acid-base slide-rule is a useful tool to carry out this five step procedure, which it simplifies, giving rapidly at the patient's bed-side an objective support for the diagnosis of acid-base disturbances. PMID:3777572

  9. Characterization of the first core sample of neutralized current acid waste from double-shell tank 101-AZ

    Peterson, M E; Scheele, R D; Tingey, J M

    1989-09-01

    In FY 1989, Westinghouse Hanford Company (WHC) successfully obtained four core samples (totaling seven segments) of neutralized current acid waste (NCAW) from double-shell tanks (DSTs) 101-AZ and 102-AZ. A segment was a 19-in.-long and 1-in.-diameter cylindrical sample of waste. A core sample consisted of enough 19-in.-long segments to obtain the waste of interest. Three core samples were obtained from DST 101-AZ and one core sample from DST 102-AZ. Two DST 101-AZ core samples consisted of two segments per core, and the third core sample consisted of only one segment. The third core consisted of the solids from the bottom of the tank and was used to determine the relative abrasiveness of this NCAW. The DST 102-AZ core sample consisted of two segments. The core samples were transported to the Pacific Northwest Laboratory (PNL), where the waste was extruded from its sampler and extensively characterized. A characterization plan was followed that simulated the processing of the NCAW samples through retrieval, pretreatment and vitrification process steps. Physical, rheological, chemical and radiochemical properties were measured throughout the process steps. The characterization of the first core sample from DST 101-AZ was completed, and the results are provided in this report. The results for the other core characterizations will be reported in future reports. 3 refs., 13 figs., 10 tabs.

  10. Current methodological approaches to determining the environmental competitiveness of products and manufacturers

    S.K. Harichkov

    2013-09-01

    Full Text Available The aim of the article. The aim of the article is to develop methodological approaches to environmental assessments and enterprise competitiveness.The results of the analysis. Ensuring environmental competitiveness of producers and their products should be based on the creation of conditions for access to restricted environmentally friendly natural resources as factors of production. Environmentally friendly products may not be carried out under conditions of companies that pollute the environment. Environmental competitiveness of producers is provided based on two of its constituent factors. First it's impact on the environment: the value of economic - environmental damage inflicted terms of air emissions, discharges into water, waste disposal in water and land facilities, depletion of all natural resources in the process of extraction and application economic-environmental damage to the environment in the extraction of natural resources. The second factor is the production of environmentally viable products. Environmental competitiveness of goods is determined by environmental parameters as a commodity and its price are acceptable to consumers and appropriate to the effective demand for certain markets in certain time periods. An important condition for the formation of the competitive nature of the process is the qualitative state factors of production, which, in turn, depends on the environmental component condition, performance, environment, sustainability of natural resource base of the national economy.To environmental performance include:level (content contaminants in combustion engines of vehicles, equipment, machinery, facilities,the probability of harmful particles, gases emissions during storage, transportation, use or consumption of goods;radioactivity of the final product and others.Methods of assessing the environmental performance of the enterprise should consist of the following steps:Gathering and analyzing baseline information

  11. Crohn`s disease: current imaging approach; Die radiologische Abklaerung des Morbus Crohn

    Schober, E.; Turetschek, K. [Klinische Abt. Roentgen fuer konservative Faecher, Universitaetsklinik fuer Radiodiagnostik, Vienna (Austria); Mostbeck, G. [Roentgeninstitut, Krankenhaus der Barmherzigen Brueder, Eisenstadt (Austria)

    1998-01-01

    Purpose: This paper discusses the role of different imaging modalities in the diagnostic work-up of Crohn`s disease (CD). Methods: We present a concept, which emphasizes different diagnostic aspects with regard to primary diagnosis, follow-up and assessment of complications of CD. The most effective imaging approach to various diagnostic problems of CD is discussed in detail. Discussion: With regard to the primary diagnosis barium studies should contribute to differentiate between CD and ulcerative colitis. Beyond that, these studies should evaluate location and extent of disease. During the follow-up bowel sonography provides staging of disease and enables the detection of complications at an early stage. CT is a valuable tool in the preoperative assessment of complications, such as fistuale and abscesses. (orig.) [Deutsch] Die vorliegende Uebersichtsarbeit soll die Rolle bildgebender radiologischer Modalitaeten bei der interdiziplinaeren Betreuung von Patienten mit Morbus Crohn (MC) diskutieren. Es wird ein Konzept vorgestellt, welches die unterschiedlichen Anforderungen an die bildgebende Diagnostik im Rahmen der Erstdiagnose, der Verlaufskontrolle sowie bei der Erfassung von Komplikationen eines MC definiert. Davon ausgehend wird versucht, fuer die einzelnen Fragestellungen die jeweils effektivste radiologische Abklaerung vorzuschlagen. Mehrere Tabellen ermoeglichen einen raschen und komprimierten Ueberblick der diagnostischen Problemstellungen im Rahmen einer schrittweisen Abklaerung der Erkrankung. Im Rahmen der Erstdiagnostik soll die radiologische Duenndarmdarstellung bei der Differentialdiagnose (MC vs. Colitis ulcerosa) hilfreich sein und das genaue Ausmass des Duenndarmbefalles eruieren. Im Rahmen der klinischen Verlaufskontrolle ist die Darmsonographie ideal zur Ueberwachung der Erkrankung sowie zur fruehen Erfassung von Komplikationen geeignet. Bei geringstem Verdacht auf eine Komplikation sollte sofort eine CT durchgefuehrt werden. (orig.)

  12. Where should Momma go? Current nursing home performance measurement strategies and a less ambitious approach

    Lieberman Trudy

    2007-06-01

    Full Text Available Abstract Background Nursing home performance measurement systems are practically ubiquitous. The vast majority of these systems aspire to rank order all nursing homes based on quantitative measures of quality. However, the ability of such systems to identify homes differing in quality is hampered by the multidimensional nature of nursing homes and their residents. As a result, the authors doubt the ability of many nursing home performance systems to truly help consumers differentiate among homes providing different levels of quality. We also argue that, for consumers, performance measurement models are better at identifying problem facilities than potentially good homes. Discussion In response to these concerns we present a proposal for a less ambitious approach to nursing home performance measurement than previously used. We believe consumers can make better informed choice using a simpler system designed to pinpoint poor-quality nursing homes, rather than one designed to rank hundreds of facilities based on differences in quality-of-care indicators that are of questionable importance. The suggested performance model is based on five principles used in the development of the Consumers Union 2006 Nursing Home Quality Monitor. Summary We can best serve policy-makers and consumers by eschewing nursing home reporting systems that present information about all the facilities in a city, a state, or the nation on a website or in a report. We argue for greater modesty in our efforts and a focus on identifying only the potentially poorest or best homes. In the end, however, it is important to remember that information from any performance measurement website or report is no substitute for multiple visits to a home at different times of the day to personally assess quality.

  13. Current status and approaches to developing press-coated chronodelivery drug systems.

    Lin, Shan-Yang; Kawashima, Yoshiaki

    2012-02-10

    recent challenges for the press coating technique. We also provide a brief overview of press-coating approaches intended for chronotherapy. PMID:21968338

  14. Review of Current Experience on Intermediate Heat Exchanger (IHX) and A Recommended Code Approach

    Duane Spencer; Kevin McCoy

    2010-02-02

    The purpose of the ASME/DOE Gen IV Task 7 Part I is to review the current experience on various high temperature reactor intermediate heat exchanger (IHX) concepts. There are several different IHX concepts that could be envisioned for HTR/VHTR applications in a range of temperature from 850C to 950C. The concepts that will be primarily discussed herein are: (1) Tubular Helical Coil Heat Exchanger (THCHE); (2) Plate-Stamped Heat Exchanger (PSHE); (3) Plate-Fin Heat Exchanger (PFHE); and (4) Plate-Machined Heat Exchanger (PMHE). The primary coolant of the NGNP is potentially subject to radioactive contamination by the core as well as contamination from the secondary loop fluid. To isolate the radioactivity to minimize radiation doses to personnel, and protect the primary circuit from contamination, intermediate heat exchangers (IHXs) have been proposed as a means for separating the primary circuit of the NGNP (Next Generation Nuclear Plant) or other process heat application from the remainder of the plant. This task will first review the different concepts of IHX that could be envisioned for HTR/VHTR applications in a range of temperature from 850 to 950 C. This will cover shell-and-tube and compact designs (including the platefin concept). The review will then discuss the maturity of the concepts in terms of design, fabricability and component testing (or feedback from experience when applicable). Particular attention will be paid to the feasibility of developing the IHX concepts for the NGNP with operation expected in 2018-2021. This report will also discuss material candidates for IHX applications and will discuss specific issues that will have to be addressed in the context of the HTR design (thermal aging, corrosion, creep, creep-fatigue, etc). Particular attention will be paid to specific issues associated with operation at the upper end of the creep regime.

  15. Long-term catheterization: current approaches in the diagnosis and treatment of port-related infections

    Bustos C

    2014-02-01

    Full Text Available Cesar Bustos,1 Aitziber Aguinaga,1 Francisco Carmona-Torre,2 Jose Luis Del Pozo1,3 1Department of Clinical Microbiology, 2Department of Internal Medicine, 3Division of Infectious Diseases, Clinica Universidad de Navarra, Pamplona, Spain Abstract: Since the first description in 1982, totally implanted venous access ports have progressively improved patients' quality of life and medical assistance when a medical condition requires the use of long-term venous access. Currently, they are part of the standard medical care for oncohematologic patients. However, apart from mechanical and thrombotic complications, there are also complications associated with biofilm development inside the catheters. These biofilms increase the cost of medical assistance and extend hospitalization. The most frequently involved micro-organisms in these infections are gram-positive cocci. Many efforts have been made to understand biofilm formation within the lumen catheters, and to resolve catheter-related infection once it has been established. Apart from systemic antibiotic treatment, the use of local catheter treatment (ie, antibiotic lock technique is widely employed. Many different antimicrobial options have been tested, with different outcomes, in clinical and in in vitro assays. The stability of antibiotic concentration in the lock solution once instilled inside the catheter lumen remains unresolved. To prevent infection, it is mandatory to perform hand hygiene before catheter insertion and manipulation, and to disinfect catheter hubs, connectors, and injection ports before accessing the catheter. At present, there are still unresolved questions regarding the best antimicrobial agent for catheter-related bloodstream infection treatment and the duration of concentration stability of the antibiotic solution within the lumen of the port. Keywords: catheter-related infection, bacteremia, biofilm

  16. Review of Current Experience on Intermediate Heat Exchanger (IHX) and A Recommended Code Approach

    The purpose of the ASME/DOE Gen IV Task 7 Part I is to review the current experience on various high temperature reactor intermediate heat exchanger (IHX) concepts. There are several different IHX concepts that could be envisioned for HTR/VHTR applications in a range of temperature from 850C to 950C. The concepts that will be primarily discussed herein are: (1) Tubular Helical Coil Heat Exchanger (THCHE); (2) Plate-Stamped Heat Exchanger (PSHE); (3) Plate-Fin Heat Exchanger (PFHE); and (4) Plate-Machined Heat Exchanger (PMHE). The primary coolant of the NGNP is potentially subject to radioactive contamination by the core as well as contamination from the secondary loop fluid. To isolate the radioactivity to minimize radiation doses to personnel, and protect the primary circuit from contamination, intermediate heat exchangers (IHXs) have been proposed as a means for separating the primary circuit of the NGNP (Next Generation Nuclear Plant) or other process heat application from the remainder of the plant. This task will first review the different concepts of IHX that could be envisioned for HTR/VHTR applications in a range of temperature from 850 to 950 C. This will cover shell-and-tube and compact designs (including the platefin concept). The review will then discuss the maturity of the concepts in terms of design, fabricability and component testing (or feedback from experience when applicable). Particular attention will be paid to the feasibility of developing the IHX concepts for the NGNP with operation expected in 2018-2021. This report will also discuss material candidates for IHX applications and will discuss specific issues that will have to be addressed in the context of the HTR design (thermal aging, corrosion, creep, creep-fatigue, etc). Particular attention will be paid to specific issues associated with operation at the upper end of the creep regime.

  17. Management of Neuropsychiatric Systemic Lupus Erythematosus: Current Approaches and Future Perspectives.

    Magro-Checa, César; Zirkzee, Elisabeth J; Huizinga, Tom W; Steup-Beekman, Gerda M

    2016-03-01

    Neuropsychiatric systemic lupus erythematosus (NPSLE) is a generic definition referring to a series of neurological and psychiatric symptoms directly related to systemic lupus erythematosus (SLE). NPSLE includes heterogeneous and rare neuropsychiatric (NP) manifestations involving both the central and peripheral nervous system. Due to the lack of a gold standard, the attribution of NP symptoms to SLE represents a clinical challenge that obligates the strict exclusion of any other potential cause. In the acute setting, management of these patients does not differ from other non-SLE subjects presenting with the same NP manifestation. Afterwards, an individualized therapeutic strategy, depending on the presenting manifestation and severity of symptoms, must be started. Clinical trials in NPSLE are scarce and most of the data are extracted from case series and case reports. High-dose glucocorticoids and intravenous cyclophosphamide remain the cornerstone for patients with severe symptoms that are thought to reflect inflammation or an underlying autoimmune process. Rituximab, intravenous immunoglobulins, or plasmapheresis may be used if response is not achieved. When patients present with mild to moderate NP manifestations, or when maintenance therapy is warranted, azathioprine and mycophenolate may be considered. When symptoms are thought to reflect a thrombotic underlying process, anticoagulation and antiplatelet agents are the mainstay of therapy, especially if antiphospholipid antibodies or antiphospholipid syndrome are present. Recent trials on SLE using new biologicals, based on newly understood SLE mechanisms, have shown promising results. Based on what we currently know about its pathogenesis, it is tempting to speculate how these new therapies may affect the management of NPSLE patients. This article provides a comprehensive and critical review of the literature on the epidemiology, pathophysiology, diagnosis, and management of NPSLE. We describe the most

  18. The roles of long-chain polyunsaturated fatty acids in pregnancy, lactation and infancy: review of current knowledge and consensus recommendations

    Koletzko, Berthold; Lien, Eric; Agostoni, Carlo; Böhles, Hansjosef; Campoy, Cristina; Cetin, Irene; Decsi, Tamas; Dudenhausen, Joachim W.; Dupont, Cristophe; Forsyth, Stewart; Hoesli, Irene; Holzgreve, Wolfgang; Lapillonne, Alexandre; Putet, Guy; Secher, Niels J.

    2008-01-01

    This paper reviews current knowledge on the role of the long-chain polyunsaturated fatty acids (LC-PUFA), docosahexaenoic acid (DHA, C22:6n-3) and arachidonic acid (AA, 20:4n-6), in maternal and term infant nutrition as well as infant development. Consensus recommendations and practice guidelines for health-care providers supported by the World Association of Perinatal Medicine, the Early Nutrition Academy, and the Child Health Foundation are provided. The fetus and neonate should receive LC-...

  19. Analysis of the low-pressure plasma pretreated polymer surface in terms of acid-base approach

    Kraus, Eduard; Orf, Lukas; Baudrit, Benjamin; Heidemeyer, Peter; Bastian, Martin; Bonenberger, Ramona; Starostina, Irina; Stoyanov, Oleg

    2016-05-01

    We demonstrate the use of a modern wetting method for determining the acid-base properties of treated polymer surfaces for different plastics and adhesives. The effect of the surface treatment with low pressure plasma was evaluated from the viewpoint of acid-base approach with plastics polyoxymethylene (POM) and polyetheretherketone (PEEK). The correlations between the acid-base properties and the identified mechanical tensile strengths of adhesive bonded joints were evaluated and discussed. In the investigated range the determination coefficients for POM and PEEK were calculated to R2 = 0.93 and R2 = 0.97, respectively. These relatively high determination coefficients showed a good correlation between the mechanical strength and the acidity parameter ΔDshort for use in bonding technology for surface pretreatment of polymers with LPP.

  20. Determination of acid ionization constants for weak acids by osmometry and the instrumental analysis self-evaluation feedback approach to student preparation of solutions

    Kakolesha, Nyanguila

    One focus of this work was to develop of an alternative method to conductivity for determining the acid ionization constants. Computer-controlled osmometry is one of the emerging analytical tools in industrial research and clinical laboratories. It is slowly finding its way into chemistry laboratories. The instrument's microprocessor control ensures shortened data collection time, repeatability, accuracy, and automatic calibration. The equilibrium constants of acetic acid, chloroacetic acid, bromoacetic acid, cyanoacetic acid, and iodoacetic acid have been measured using osmometry and their values compared with the existing literature values obtained, usually, from conductometric measurements. Ionization constant determined by osmometry for the moderately strong weak acids were in reasonably good agreement with literature values. The results showed that two factors, the ionic strength and the osmotic coefficient, exert opposite effects in solutions of such weak acids. Another focus of the work was analytical chemistry students solution preparation skills. The prevailing teacher-structured experiments leave little room for students' ingenuity in quantitative volumetric analysis. The purpose of this part of the study was to improve students' skills in making solutions using instrument feedback in a constructivist-learning model. After making some solutions by weighing and dissolving solutes or by serial dilution, students used the spectrophotometer and the osmometer to compare their solutions with standard solutions. Students perceived the instrument feedback as a nonthreatening approach to monitoring the development of their skill levels and liked to clarify their understanding through interacting with an instructor-observer. An assessment of the instrument feedback and the constructivist model indicated that students would assume responsibility for their own learning if given the opportunity. This study involved 167 students enrolled in Quantitative Chemical

  1. [Overwork and its health effects--current status and future approach regarding Karoshi].

    Hoshuyama, Tsutomu

    2003-09-01

    The word karoshi, i.e. death due to overwork, is not defined for medical diagnosis, but in Japan it means cases of compensation awarded by reason of fatal occupational diseases, particularly ischemic heart diseases and cerebrovascular diseases which are recognized as caused by a heavy workload. Current studies have shown that 1) almost definitely there is evidence of an association between overwork and cardiovascular diseases and the risk factors were found, 2) no reports have been published on evidence of a causal relationship between overwork and fatal effects even though the possibility remains, and 3) the adverse health effects can vary according to workers' characteristics such as gender, age, stress coping and perception. Recently there has been an increase in the proportion of compensated cases versus claims from 3.1% in the 1988 fiscal year to 20.7% in the 2001 fiscal year. This may be related to the deregulation of criteria for compensation, or nintei-kijun. The period of determination of overwork for victims has been extended to a maximum of six months in the newest criteria set in 2001, up from only one week in the criteria set in 1987. According to sociological analysis, long working hours in Japan are related not only to the structure of the working-time system but also the sociocultural background of labor. In 2002, the Japanese government provided the first countermeasures for the prevention of karoshi for all employees stating that they should not work more than 45 h overtime per month and that government intervention in the form of administrative guidance to employees and their employers should be conducted if overtime exceeds 100 h per month. It is a population strategy targeting all workers equally, not just a high-risk strategy targeting only those with some risk factors, and is expected to provide more fruitful results with flexibility, i.e. differentially reinforced management for older workers and those working under highly stressful

  2. Lewis Acid-Base Adduct Approach for High Efficiency Perovskite Solar Cells.

    Lee, Jin-Wook; Kim, Hui-Seon; Park, Nam-Gyu

    2016-02-16

    Since the first report on the long-term durable 9.7% solid-state perovskite solar cell employing methylammonium lead iodide (CH3NH3PbI3), mesoporous TiO2, and 2,2',7,7'-tetrakis[N,N-di(4-methoxyphenyl)amino]-9,9'-spirobifluorene (spiro-MeOTAD) in 2012, following the seed technologies on perovskite-sensitized liquid junction solar cells in 2009 and 2011, a surge of interest has been focused on perovskite solar cells due to superb photovoltaic performance and extremely facile fabrication processes. The power conversion efficiency (PCE) of perovskite solar cells reached 21% in a very short period of time. Such an unprecedentedly high photovoltaic performance is due to the intrinsic optoelectronic property of organolead iodide perovskite material. Moreover, a high dielectric constant, sub-millimeter scale carrier diffusion length, an underlying ferroelectric property, and ion migration behavior can make organolead halide perovskites suitable for multifunctionality. Thus, besides solar cell applications, perovskite material has recently been applied to a variety fields of materials science such as photodetectors, light emitting diodes, lasing, X-ray imaging, resistive memory, and water splitting. Regardless of application areas, the growth of a well-defined perovskite layer with high crystallinity is essential for effective utilization of its excellent physicochemical properties. Therefore, an effective methodology for preparation of high quality perovskite layers is required. In this Account, an effective methodology for production of high quality perovskite layers is described, which is the Lewis acid-base adduct approach. In the solution process to form the perovskite layer, the key chemicals of CH3NH3I (or HC(NH2)2I) and PbI2 are used by dissolving them in polar aprotic solvents. Since polar aprotic solvents bear oxygen, sulfur, or nitrogen, they can act as a Lewis base. In addition, the main group compound PbI2 is known to be a Lewis acid. Thus, PbI2 has a chance

  3. Improving the management of infertile acid soils in Southeast Asia: The approach of the IBSRAM Acid-Soils network

    The IBSRAM ASIALAND Management of Acid Soils network aims to improve the understanding of the broad range of biophysical and socio-economic production limitations on infertile acid soils of Southeast Asia, and to lead to development and implementation of sustainable land-management strategies for these important marginal areas. The main activities of the network are in Indonesia, Myanmar, Philippines, and Vietnam, with associated activity in Thailand, and minor involvement in Brunei, Cambodia, Laos, and Malaysia. The main experimental focus is through researcher-managed on-farm trials, to improve the management of phosphorus nutrition with inorganic and organic amendments. A generic design is used across the eight well characterised sites that form the core of the network. The results will be analysed across time and across sites. Improved methods for laboratory analyses, experimental management, socio-economic data collection, and data analysis and interpretation are critical components. Three important initiatives are associated with the core activities. These aim to establish a broader network on maintenance of quality laboratory analyses, to assess the potential for implementation of improved strategies through farmer-managed on-farm trials, and to improve our understanding of, and ways of estimating, nutrient budgets for diverse farming systems. (author)

  4. Noninvasive nucleic acid-based approaches to monitor placental health and predict pregnancy-related complications.

    Manokhina, Irina; Wilson, Samantha L; Robinson, Wendy P

    2015-10-01

    During pregnancy, the placenta releases a variety of nucleic acids (including deoxyribonucleic acid, messenger ribonucleic acid, or microribonucleic acids) either as a result of cell turnover or as an active messaging system between the placenta and cells in the maternal body. The profile of released nucleic acids changes with the gestational age and has been associated with maternal and fetal parameters. It also can directly reflect pathological changes in the placenta. Nucleic acids may therefore provide a rich source of novel biomarkers for the prediction of pregnancy complications. However, their utility in the clinical setting depends, first, on overcoming some technical considerations in their quantification, and, second, on developing a better understanding of the factors that influence their function and abundance. PMID:26428499

  5. Effect of suppressor current intensity on the determination of glyphosate and aminomethylphosphonic acid by suppressed conductivity ion chromatography.

    Dimitrakopoulos, Ioannis K; Thomaidis, Nikolaos S; Megoulas, Nikolaos C; Koupparis, Michael A

    2010-05-28

    This paper presents the application of ion chromatography with electrolytic eluent generation and mobile phase suppression for the direct conductimetric detection of glyphosate and its degradation product aminomethylphosphonic acid (AMPA). The compounds were separated on a Dionex AS18 anion exchange column with a 12-40 mM KOH step gradient from 9 to 9.5 min. The effect of the suppressor current intensity on the electrostatic interaction of these amphoteric compounds with the suppressor cation exchange membranes was evaluated. A suppressor current gradient technique was proposed for the limitation of peak broadening and baseline noise, in order to improve method sensitivity and detectability. It was observed that residual sample carbonates co-eluted with AMPA when a large injection loop was installed for the low level determination of both compounds in natural waters. For this reason, glyphosate was isocratically eluted using 33 mM KOH in order to decrease analysis time within 10 min and a column clean up step using 100 mM KOH was used to ensure retention time reproducibility. The developed method was applied to the analysis of drinking and natural water and it was further successfully applied to orange samples with slight modifications. Instrumental LOD for glyphosate was 0.24 microg/L, while method LOD was 0.54 microg/L for spring waters and 0.01 mg/kg for oranges using a 1000 microL direct loop injection of the sample. Intra-day and inter-day precision (as %RSD) for water samples was 4.6% and 12% at a spiking level of 2 microg/L, and the recovery ranged from 64% to 88% depending on sample conductivity. For orange samples, the inter-day precision was 1.4% at a spiking level of 4.4 mg/kg, while overall recovery was 103%. The developed method is direct, fast, sensitive and relatively inexpensive, and could be used as an ideal fast screening tool for the monitoring of glyphosate residues in water and fruit samples. PMID:20399436

  6. Transient Receptor Potential Vanilloid 4 Inhibits γ-Aminobutyric Acid-Activated Current in Hippocampal Pyramidal Neurons

    Hong, Zhiwen; Tian, Yujing; Qi, Mengwen; Li, Yingchun; Du, Yimei; Chen, Lei; Liu, Wentao; Chen, Ling

    2016-01-01

    The balance between excitatory and inhibitory neurotransmitter systems is crucial for the modulation of neuronal excitability in the central nervous system (CNS). The activation of transient receptor potential vanilloid 4 (TRPV4) is reported to enhance the response of hippocampal glutamate receptors, but whether the inhibitory neurotransmitter system can be regulated by TRPV4 remains unknown. γ-aminobutyric acid (GABA) is the major inhibitory neurotransmitter in the CNS. Here, we show that application of transient receptor potential vanilloid 4 (TRPV4) synthetic (GSK1016790A or 4α-PDD) or endogenous agonist (5,6-EET) inhibited GABA-activated current (IGABA) in hippocampal CA1 pyramidal neurons, which was blocked by specific antagonists of TRPV4 and of GABAA receptors. GSK1016790A increased the phosphorylated AMP-activated protein kinase (p-AMPK) and decreased the phosphorylated protein kinase B (p-Akt) protein levels, which was attenuated by removing extracellular calcium or by a calcium/calmodulin-dependent protein kinase kinase-β antagonist. GSK1016790A-induced decrease of p-Akt protein level was sensitive to an AMPK antagonist. GSK1016790A-inhibited IGABA was blocked by an AMPK antagonist or a phosphatidyl inositol 3 kinase (PI3K) agonist. GSK1016790A-induced inhibition of IGABA was also significantly attenuated by a protein kinase C (PKC) antagonist but was unaffected by protein kinase A or calcium/calmodulin-dependent protein kinase II antagonist. We conclude that activation of TRPV4 inhibits GABAA receptor, which may be mediated by activation of AMPK and subsequent down-regulation of PI3K/Akt signaling and activation of PKC signaling. Inhibition of GABAA receptors may account for the neuronal hyperexcitability caused by TRPV4 activation.

  7. A diagrammatic description of the equations of motion, current and noise within the second-order von Neumann approach

    We investigate the second-order von Neumann approach from a diagrammatic point of view and demonstrate its equivalence with the resonant tunneling approximation. The investigation of higher order diagrams shows that the method correctly reproduces the equation of motion for the single-particle reduced density matrix of an arbitrary non-interacting many-body system. This explains why the method reproduces the current exactly for such systems. We go on to show, however, that diagrams not included in the method are needed to calculate exactly higher cumulants of the charge transport. This thorough comparison sheds light on the validity of all these self-consistent second-order approaches. We analyze the discrepancy between the noise calculated by our method and the exact Levitov formula for a simple non-interacting quantum dot model. Furthermore, we study the noise of the canyon of current suppression in a two-level dot, a phenomenon that requires the inclusion of electron–electron interaction as well as higher order tunneling processes. (paper)

  8. Structural Investigation for Optimization of Anthranilic Acid Derivatives as Partial FXR Agonists by in Silico Approaches

    Meimei Chen

    2016-04-01

    Full Text Available In this paper, a three level in silico approach was applied to investigate some important structural and physicochemical aspects of a series of anthranilic acid derivatives (AAD newly identified as potent partial farnesoid X receptor (FXR agonists. Initially, both two and three-dimensional quantitative structure activity relationship (2D- and 3D-QSAR studies were performed based on such AAD by a stepwise technology combined with multiple linear regression and comparative molecular field analysis. The obtained 2D-QSAR model gave a high predictive ability (R2train = 0.935, R2test = 0.902, Q2LOO = 0.899. It also uncovered that number of rotatable single bonds (b_rotN, relative negative partial charges (RPC−, oprea's lead-like (opr_leadlike, subdivided van der Waal’s surface area (SlogP_VSA2 and accessible surface area (ASA were important features in defining activity. Additionally, the derived3D-QSAR model presented a higher predictive ability (R2train = 0.944, R2test = 0.892, Q2LOO = 0.802. Meanwhile, the derived contour maps from the 3D-QSAR model revealed the significant structural features (steric and electronic effects required for improving FXR agonist activity. Finally, nine newly designed AAD with higher predicted EC50 values than the known template compound were docked into the FXR active site. The excellent molecular binding patterns of these molecules also suggested that they can be robust and potent partial FXR agonists in agreement with the QSAR results. Overall, these derived models may help to identify and design novel AAD with better FXR agonist activity.

  9. Structural Investigation for Optimization of Anthranilic Acid Derivatives as Partial FXR Agonists by in Silico Approaches.

    Chen, Meimei; Yang, Xuemei; Lai, Xinmei; Kang, Jie; Gan, Huijuan; Gao, Yuxing

    2016-01-01

    In this paper, a three level in silico approach was applied to investigate some important structural and physicochemical aspects of a series of anthranilic acid derivatives (AAD) newly identified as potent partial farnesoid X receptor (FXR) agonists. Initially, both two and three-dimensional quantitative structure activity relationship (2D- and 3D-QSAR) studies were performed based on such AAD by a stepwise technology combined with multiple linear regression and comparative molecular field analysis. The obtained 2D-QSAR model gave a high predictive ability (R²train = 0.935, R²test = 0.902, Q²LOO = 0.899). It also uncovered that number of rotatable single bonds (b_rotN), relative negative partial charges (RPC(-)), oprea's lead-like (opr_leadlike), subdivided van der Waal's surface area (SlogP_VSA2) and accessible surface area (ASA) were important features in defining activity. Additionally, the derived3D-QSAR model presented a higher predictive ability (R²train = 0.944, R²test = 0.892, Q²LOO = 0.802). Meanwhile, the derived contour maps from the 3D-QSAR model revealed the significant structural features (steric and electronic effects) required for improving FXR agonist activity. Finally, nine newly designed AAD with higher predicted EC50 values than the known template compound were docked into the FXR active site. The excellent molecular binding patterns of these molecules also suggested that they can be robust and potent partial FXR agonists in agreement with the QSAR results. Overall, these derived models may help to identify and design novel AAD with better FXR agonist activity. PMID:27070594

  10. Structural Investigation for Optimization of Anthranilic Acid Derivatives as Partial FXR Agonists by in Silico Approaches

    Chen, Meimei; Yang, Xuemei; Lai, Xinmei; Kang, Jie; Gan, Huijuan; Gao, Yuxing

    2016-01-01

    In this paper, a three level in silico approach was applied to investigate some important structural and physicochemical aspects of a series of anthranilic acid derivatives (AAD) newly identified as potent partial farnesoid X receptor (FXR) agonists. Initially, both two and three-dimensional quantitative structure activity relationship (2D- and 3D-QSAR) studies were performed based on such AAD by a stepwise technology combined with multiple linear regression and comparative molecular field analysis. The obtained 2D-QSAR model gave a high predictive ability (R2train = 0.935, R2test = 0.902, Q2LOO = 0.899). It also uncovered that number of rotatable single bonds (b_rotN), relative negative partial charges (RPC−), oprea's lead-like (opr_leadlike), subdivided van der Waal’s surface area (SlogP_VSA2) and accessible surface area (ASA) were important features in defining activity. Additionally, the derived3D-QSAR model presented a higher predictive ability (R2train = 0.944, R2test = 0.892, Q2LOO = 0.802). Meanwhile, the derived contour maps from the 3D-QSAR model revealed the significant structural features (steric and electronic effects) required for improving FXR agonist activity. Finally, nine newly designed AAD with higher predicted EC50 values than the known template compound were docked into the FXR active site. The excellent molecular binding patterns of these molecules also suggested that they can be robust and potent partial FXR agonists in agreement with the QSAR results. Overall, these derived models may help to identify and design novel AAD with better FXR agonist activity. PMID:27070594

  11. Specificity of the Acute Tryptophan and Tyrosine Plus Phenylalanine Depletion and Loading Tests I. Review of Biochemical Aspects and Poor Specificity of Current Amino Acid Formulations

    Abdulla A.-B. Badawy

    2010-06-01

    Full Text Available The acute tryptophan or tyrosine plus phenylalanine depletion and loading tests are powerful tools for studying the roles of serotonin, dopamine and noradrenaline in normal subjects and those with behavioural disorders. The current amino acid formulations for these tests, however, are associated with undesirable decreases in ratios of tryptophan or tyrosine plus phenylalanine to competing amino acids resulting in loss of specificity. This could confound biochemical and behavioural findings. Compositions of current formulations are reviewed, the biochemical principles underpinning the tests are revisited and examples of unintended changes in the above ratios and their impact on monoamine function and behaviour will be demonstrated from data in the literature. The presence of excessive amounts of the 3 branched-chain amino acids Leu, Ile and Val is responsible for these unintended decreases and the consequent loss of specificity. Strategies for enhancing the specificity of the different formulations are proposed.

  12. Electrolytic deposition of calcium phosphate/chitosan coating on titanium alloy: Growth kinetics and influence of current density, acetic acid, and chitosan

    Wang, Jiawei; Apeldoorn, van Aart; Groot, de Klaas

    2006-01-01

    Electrolytically deposited calcium phosphate/chitosan coating demonstrated good bone marrow stromal cell attachment. The aim of this study was to understand the coating's growth kinetics as well as the effects of current density, acetic acid, and chitosan on the coating's formation. The scanning ele

  13. The current CEA/DRN safety approach for the design and the assessment of future nuclear installations

    The purpose of the document is to present the basis of the safety approach currently implemented by the CEA/DRN, both for the design and the assessment of innovative systems and future nuclear installations. This approach is the result of the experience maturated, within the context of the CEA/DRN Innovative Programme through practical applications over several future concepts, both for fission and fusion reactors, as well as for waste disposal. The background of this experience is structured coherently with the European Safety Authorities recommendations and the European Utilities Requirements (EUR). The Defence In Depth principle and its application, by means, among others, of the barrier concept, remains the basis of the safety design process of future nuclear installations. Its adequacy is checked through the safety assessment. The methodology for Lines Of Defence (LOD) implementation as well as the one for the LOD architecture assessment is shown and motivated. The document shows that the clear and unambiguous definition of the safety approach provides an essential base for the organisation of the design tasks, being sure that the safety aspects are correctly taken into account and implemented, and for an adequate safety assessment of the final design, both from qualitative point of view as well as for the quantitative safety analysis. (author)

  14. Light-cone AdS/CFT-adapted approach to AdS fields/currents, shadows, and conformal fields

    Metsaev, R R

    2015-01-01

    Light-cone gauge formulation of fields in AdS space and conformal field theory in flat space adapted for the study of AdS/CFT correspondence is developed. Arbitrary spin mixed-symmetry fields in AdS space and arbitrary spin mixed-symmetry currents, shadows, and conformal fields in flat space are considered on an equal footing. For the massless and massive fields in AdS and the conformal fields in flat space, simple light-cone gauge actions leading to decoupled equations of motion are found. For the currents and shadows, simple expressions for all 2-point functions are also found. We demonstrate that representation of conformal algebra generators on space of currents, shadows, and conformal fields can be built in terms of spin operators entering the light-cone gauge formulation of AdS fields. This considerably simplifies the study of AdS/CFT correspondence. Light-cone gauge actions for totally symmetric arbitrary spin long conformal fields in flat space are presented. We apply our approach to the study of tota...

  15. Inspiration from the mirror: D-amino acid containing peptides in biomedical approaches.

    Feng, Zhaoqianqi; Xu, Bing

    2016-06-01

    D-amino acids, the enantiomers of naturally abundant L-amino acids, bear unique stereochemistry properties that lead to the resistance towards most of the endogenous enzymes. Previous works have demonstrated applications of D-amino acids in therapeutic development with the aid of mirror-image phage display and retro-inverso peptide synthesis. In this review, we highlight the recent progress and challenges in the exploration of D-amino acids at the interface of chemistry and life science. First, we will introduce some progress made in traditional application of D-amino acids to enhance biostability of peptide therapeutics. Then, we discuss some works that explore the relatively underexplored interactions between the enzyme and D-amino acids and enzymatic reactions of D-amino acids. To highlight the enzymatic reactions of D-amino acids, we will describe several emerging works on the enzyme-instructed self-assembly (EISA) and their potential application in selective anti-inflammatory or anticancer therapies. At the end, we briefly mention the challenges and possible future directions. PMID:27159920

  16. Stereoselective synthesis of a-hydroxy-b-amino acids: the chiral pool approach

    RADOMIR N. SAICIC

    2004-11-01

    Full Text Available A method for the stereoselective homologation of a-amino acids into syn-a-hydroxy-b-amino acids is described, based on the conversion of stereoisomeric cyanohydrins into trans-oxazolines. The synthetic potential of the method is illustrated in the enantioselective formal synthesis of Bestatin.

  17. A new look at liming as an approach to accelerate recovery from acidic deposition effects.

    Lawrence, Gregory B; Burns, Douglas A; Riva-Murray, Karen

    2016-08-15

    Acidic deposition caused by fossil fuel combustion has degraded aquatic and terrestrial ecosystems in North America for over four decades. The only management option other than emissions reductions for combating the effects of acidic deposition has been the application of lime to neutralize acidity after it has been deposited on the landscape. For this reason, liming has been a part of acid rain science from the beginning. However, continued declines in acidic deposition have led to partial recovery of surface water chemistry, and the start of soil recovery. Liming is therefore no longer needed to prevent further damage, so the question becomes whether liming would be useful for accelerating recovery of systems where improvement has lagged. As more is learned about recovering ecosystems, it has become clear that recovery rates vary with watershed characteristics and among ecosystem components. Lakes appear to show the strongest recovery, but recovery in streams is sluggish and recovery of soils appears to be in the early stages. The method in which lime is applied is therefore critical in achieving the goal of accelerated recovery. Application of lime to a watershed provides the advantage of increasing Ca availability and reducing or preventing mobilization of toxic Al, an outcome that is beneficial to both terrestrial and aquatic ecosystems. However, the goal should not be complete neutralization of soil acidity, which is naturally produced. Liming of naturally acidic areas such as wetlands should also be avoided to prevent damage to indigenous species that rely on an acidic environment. PMID:27092419

  18. Mechanism of cinnamic acid-induced trypsin inhibition: A multi-technique approach

    Zhang, Hongmei; Zhou, Qiuhua; Cao, Jian; Wang, Yanqing

    2013-12-01

    In order to investigate the association of the protease trypsin with cinnamic acid, the interaction was characterized by using fluorescence, UV-vis absorption spectroscopy, molecular modeling and an enzymatic inhibition assay. The binding process may be outlined as follows: cinnamic acid can interact with trypsin with one binding site to form cinnamic acid-trypsin complex, resulting in inhibition of trypsin activity; the spectroscopic data show that the interaction is a spontaneous process with the estimated enthalpy and entropy changes being -8.95 kJ mol-1 and 50.70 J mol-1 K-1, respectively. Noncovalent interactions make the main contribution to stabilize the trypsin-cinnamic acid complex; cinnamic acid can enter into the primary substrate-binding pocket and alter the environment around Trp and Tyr residues.

  19. Economic evaluations of pharmacogenetic approaches in infectious diseases: a review of current approaches and evaluation of critical aspects affecting their quality

    Paolo Meoni

    2013-11-01

    Full Text Available Pharmacogenetics holds great potential for improving the effectiveness of treatment modalities in infectious diseases by taking into account the genetic determinants of both the host and infectious agents’ individuality. Better utilization of resources and improved therapeutic efficiency are the expected outcomes of personalized medicine using pharmacogenetic and pharmacogenomics information made available by technological advances. However, there has been growing concern in the clinical community regarding the evaluation of the true benefits of these approaches. This perception is partly due to the limited number and perceived poor quality of economic evaluations in this field, and initiatives aimed at harmonizing and communicating strategies improving the quality of these studies and their acceptance by the clinical community are greatly needed. This paper reviews current literature of economic evaluations of pharmacogenetics interventions guiding pharmacotherapy in infectious diseases. PubMed and the NHS Centre for Reviews and Dissemination databases were searched using a combination of five broad research terms related to pharmacogenetic approaches, and papers relative to economic evaluations of pharmacogenetic interventions in infectious diseases retained for further analysis. Using these criteria, a total of 14 papers were included in this review. The area of economic evaluation of pharmacogenetic interventions in infectious diseases remains understudied and would benefit from greater harmonization. The main weaknesses of evaluations reviewed in this paper seem to be represented by poor evidence of pharmacogenetic marker validation, inconsistencies in the selection of costs and utility included in the economic models and the choice of sensitivity analysis. All these factors limit the overall transparency of the studies, greater acceptance of their results and applicability to diverse and possibly resourcelimited environments where these

  20. Current approaches to treatments for schizophrenia spectrum disorders, part II: psychosocial interventions and patient-focused perspectives in psychiatric care

    Chien WT

    2013-09-01

    functioning, and/or relapse rate. However, the comparative effects between these five approaches have not been well studied; thus, we are not able to clearly understand the superiority of any of these interventions. With the exception of patient relapse, the longer-term (eg, >2 years effects of these approaches on most psychosocial outcomes are not well-established among these patients. Despite the fact that patients' perspectives on treatment and care have been increasingly concerned, not many studies have evaluated the effect of interventions on this perspective, and where they did, the findings were inconclusive. To conclude, current approaches to psychosocial interventions for schizophrenia have their strengths and weaknesses, particularly indicating limited evidence on long-term effects. To improve the longer-term outcomes of people with schizophrenia, future treatment strategies should focus on risk identification, early intervention, person-focused therapy, partnership with family caregivers, and the integration of evidence-based psychosocial interventions into existing services. Keywords: schizophrenia, psychosocial intervention, patient-focused perspectives

  1. Small-scale spatial variability of phenoxy acid mineralization potentials in transition zones with a multidisciplinary approach

    Pazarbasi, Meric Batioglu

    , the challenge of small-scale spatial variability occurs in terms of microbiological and physicochemical properties. We used genomic- and metagenomic-based approaches to reveal the effects of long-term phenoxy acid in situ exposure on the small-scale spatial variability of herbicide mineralization potentials...... in two transition zones, (1) the interfaces of unsaturated and saturated zones and (2) groundwater and surface water. Small-scale spatial variability of phenoxy acids was previously shown in topsoil; however, such small-scale studies are scarce in subsurface environments. We therefore studied the factors...... shaping the centimetre-scale vertical variability of phenoxy acid degradation in the interface of unsaturated and saturated zones. We demonstrated more even centimetre-scale vertical distribution of MCPA mineralization potential than that of 2,4-D at the concentration of 1 mg kg-1, and the mineralization...

  2. Application of a Mass Spectrometric Approach to Detect the Presence of Fatty Acid Biosynthetic Phosphopeptides.

    Lau, Benjamin Yii Chung; Clerens, Stefan; Morton, James D; Dyer, Jolon M; Deb-Choudhury, Santanu; Ramli, Umi Salamah

    2016-04-01

    The details of plant lipid metabolism are relatively well known but the regulation of fatty acid production at the protein level is still not understood. Hence this study explores the importance of phosphorylation as a mechanism to control the activity of fatty acid biosynthetic enzymes using low and high oleic acid mesocarps of oil palm fruit (Elaeis guineensis variety of Tenera). Adaptation of neutral loss-triggered tandem mass spectrometry and selected reaction monitoring to detect the neutral loss of phosphoric acid successfully found several phosphoamino acid-containing peptides. These peptides corresponded to the peptides from acetyl-CoA carboxylase and 3-enoyl-acyl carrier protein reductase as identified by their precursor ion masses. These findings suggest that these enzymes were phosphorylated at 20th week after anthesis. Phosphorylation could have reduce their activities towards the end of fatty acid biosynthesis at ripening stage. Implication of phosphorylation in the regulation of fatty acid biosynthesis at protein level has never been reported. PMID:26993480

  3. Novel Approach: Tungsten Oxide Nanoparticle as a Catalyst for Malonic Acid Ester Synthesis via Ozonolysis

    Bilal A. Wasmi

    2014-01-01

    Full Text Available Malonic acid ester was synthesized via the one-step ozonolysis of palm olein. Malonic acid ester was spectroscopically characterized using gas chromatography mass spectroscopy (GC-MS. Tungsten oxide nanoparticles were used as the catalyst, which was characterized via X-ray powder diffraction (XRD and field emission scanning electron microscopy (FE-SEM. Tungsten oxide provided several advantages as a catalyst for the esterification malonic acid such as simple operation for a precise ozonation method, an excellent yield of approximately 10%, short reaction times of 2 h, and reusability due to its recyclability.

  4. Synthesis of nucleotide–amino acid conjugates designed for photo-CIDNP experiments by a phosphotriester approach

    Tatyana V. Abramova

    2013-12-01

    Full Text Available Conjugates of 2’-deoxyguanosine, L-tryptophan and benzophenone designed to study pathways of fast radical reactions by the photo Chemically Induced Dynamic Nuclear Polarization (photo-CIDNP method were obtained by the phosphotriester block liquid phase synthesis. The phosphotriester approach to the oligonucleotide synthesis was shown to be a versatile and economic strategy for preparing the required amount of high quality samples of nucleotide–amino acid conjugates.

  5. Current Perspectives on Novel Drug Delivery Systems and Approaches for Management of Cervical Cancer: A Comprehensive Review.

    Hani, Umme; Osmani, Riyaz Ali M; Bhosale, Rohit R; Shivakumar, Hosakote Gurumallappa; Kulkarni, Parthasarathi K

    2016-01-01

    Cervical cancer is uterine cervix carcinoma, the second deadly cancer and has a high incidence and mortality rate. In the developing world conventional treatment strategies such as surgical intervention and chemoradiotherapy are less widely available. Currently cancer research focuses on improving treatment of cervical cancer using various therapies such as gene therapy, recombinant protein therapy, photodynamic therapy, photothermal therapy and delivery of chemotherapeutic agents using nanoparticles, hydrogel and liposomal based delivery systems and also localized delivery systems which exist in a variety of forms such as intravaginal rings, intravaginal patches, intravaginal films, etc. in order to improve the drug delivery in a controlled manner to the diseased site thereby reducing systemic side effects. The present review encloses existing diverse delivery systems and approaches intended for treatment of cervical cancer. PMID:25944014

  6. Current approaches to improve the anticancer chemotherapy with alkylating agents: state of the problem in world and Ukraine.

    Iatsyshyna A. P.

    2012-01-01

    Full Text Available Alkylating agents are frequently used in many established anticancer chemotherapies. They alkylate the genomic DNA at various sites. Alkylation of the guanine at the O6-position is cytotoxic, it has the strongest mutagenic potential, as well as can cause the tumor development. Alkyl groups at the O6-position of guanine are removed by the DNA repair enzyme O6-methylguanine-DNA methyltransferase (MGMT. The effectiveness of alkylating chemotherapy is limited by MGMT in cancer cells and adverse toxic side effects in normal cells. Different approaches consisting in the modulation of the MGMT expression and activity are under development now to improve the cancer chemotherapy. They include two main directions, in particular, the increase in chemosensitivity of cancer cells to alkylating drugs and the protection of normal cells from the toxic side effects of chemotherapy. This review is focused on current attempts to improve the alkylating chemotherapy of malignant tumours worldwide and state of the issue in Ukraine

  7. Current Perspective on the Location and Function of Gamma- Aminobutyric Acid (GABA) and its Metabolic Partners in the Kidney.

    Dunn, Kadeshia; Peppiatt-Wildman, Claire M.; Kelley, Stephen P; Wildman, Scott S.P.

    2014-01-01

    Abstract: Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter located in the mammalian central nervous system, which binds to GABAA and GABAB receptors to mediate its neurological effects. In addition to its role in the CNS, an increasing number of publications have suggested that GABA might also play a role in the regulation of renal function. All three enzymes associated with GABA metabolism; glutamic acid decarboxylase, GABA α-oxoglutarate transaminase (GABA-T) and succinic se...

  8. An Approach to Reduce Load on the Acid Leaching Circuit of the Commercial Uranium Recovery Plant at Jaduguda, India

    Rao, G. V.; Prakash, S.

    1998-01-01

    The commercial uranium recovery plant at Jaduguda, Bihar, India, currently treats around 900 tonnes of ore per day from the Jaduguda mine, containing around 0.05% U3O8. Subsequent to removal of the sulphide minerals present in the ore by flotation, nearly 95% of the tailings are being treated in the acid leaching circuit to recover the uranium values. Laboratory investigations on the bulk flotation tailings revealed that around 63% of the uranium values are associated with feebly magnetic mat...

  9. An automatic system for acidity determination based on sequential injection titration and the monosegmented flow approach.

    Kozak, Joanna; Wójtowicz, Marzena; Gawenda, Nadzieja; Kościelniak, Paweł

    2011-06-15

    An automatic sequential injection system, combining monosegmented flow analysis, sequential injection analysis and sequential injection titration is proposed for acidity determination. The system enables controllable sample dilution and generation of standards of required concentration in a monosegmented sequential injection manner, sequential injection titration of the prepared solutions, data collecting, and handling. It has been tested on spectrophotometric determination of acetic, citric and phosphoric acids with sodium hydroxide used as a titrant and phenolphthalein or thymolphthalein (in the case of phosphoric acid determination) as indicators. Accuracy better than |4.4|% (RE) and repeatability better than 2.9% (RSD) have been obtained. It has been applied to the determination of total acidity in vinegars and various soft drinks. The system provides low sample (less than 0.3 mL) consumption. On average, analysis of a sample takes several minutes. PMID:21641455

  10. Extraction of Phthalic Acid from Aqueous Solution by Using Ionic Liquids: A Quantum Chemical Approach

    Pilli, S; Mohanty, Kaustubha; Banerjee, Tamal

    2014-01-01

    Phthalic acid is an industrial chemical and it comes under the domain of endocrine disrupting chemicals (EDCs). Green solvents such as ionic liquids (ILs) posses good extractable capabilities for EDCs. COSMO–RS methodology is a widely accepted method for the design or selection of ionic liquids. COSMO–RS is a quantum chemical based method based on COSMO polarization charge densities. In this work the model has been used to screen the potential ionic liquids for the removal of phthalic acid fr...

  11. Biocatalyzed approach for the surface functionalization of poly(L-lactic acid) films using hydrolytic enzymes.

    Pellis, Alessandro; Acero, Enrique Herrero; Weber, Hansjoerg; Obersriebnig, Michael; Breinbauer, Rolf; Srebotnik, Ewald; Guebitz, Georg M

    2015-09-01

    Poly(lactic acid) as a biodegradable thermoplastic polyester has received increasing attention. This renewable polyester has found applications in a wide range of products such as food packaging, textiles and biomedical devices. Its major drawbacks are poor toughness, slow degradation rate and lack of reactive side-chain groups. An enzymatic process for the grafting of carboxylic acids onto the surface of poly(L-lactic acid) (PLLA) films was developed using Candida antarctica lipase B as a catalyst. Enzymatic hydrolysis of the PLLA film using Humicola insolens cutinase in order to increase the number of hydroxyl and carboxylic groups on the outer polymer chains for grafting was also assessed and showed a change of water contact angle from 74.6 to 33.1° while the roughness and waviness were an order of magnitude higher in comparison to the blank. Surface functionalization was demonstrated using two different techniques, (14) C-radiochemical analysis and X-ray photoelectron spectroscopy (XPS) using (14) C-butyric acid sodium salt and 4,4,4-trifluorobutyric acid as model molecules, respectively. XPS analysis showed that 4,4,4-trifluorobutyric acid was enzymatically coupled based on an increase of the fluor content from 0.19 to 0.40%. The presented (14) C-radiochemical analyses are consistent with the XPS data indicating the potential of enzymatic functionalization in different reaction conditions. PMID:25963883

  12. Overview of current approaches regarding the use of water to cool a molten core in the containment in ten OECD member countries

    Several countries have implemented new measures to cope with severe accidents. Of key importance is the possibility to cool the core debris in the containment and the strategy formed to accomplish this. If the core debris can be cooled pressure build-up will cease and the containment basemat will not be penetrated. The importance of this issue has been acknowledged in the development of new designs of nuclear reactors. CSNI/PWG4 task group on Containment Aspects of Severe Accident Management (CAM) started to investigate this issue in 1992. The first of a three stage approach was to investigate current accident management strategies in Member countries, identify the reasons for choosing these strategies, and consider if solutions proposed for future reactors could be applied to current reactors. A questionnaire has been sent out to the member countries. This technical report is based on the answers prepared by 10 member countries (Belgium, Finland, France, Germany, Japan, Netherlands, Spain, Sweden, Switzerland and United States), representing both BWR and PWR of different designs. In the questionnaire the member countries were asked to specify the area below the cavity, material, basement thickness, possible weaknesses, strategy chosen and the reasons for the selected strategy. The report includes three parts: current designs and strategy approaches for BWR (design of volume below reactor vessel, current approaches to cool the melted core); current designs and strategy approaches for PWR (cavity design, current approaches to cool the melted core); discussion of advantages and consequences of current strategy approaches

  13. Current challenges and innovative approaches in the development of peripheral regions in Bulgaria: The case of Ivaylovgrad municipality

    Dimitrova Elena

    2010-01-01

    Full Text Available The paper approaches territorial cohesion in SEE from the perspective of social equity with regard to the opportunity to choose to live in one’s native place without compromising the quality of life. It is interested in border areas - both physical and virtual; in real life situations as meeting points of theories and policies influencing human lives; and in the emerging challenges there that often make us question once and again our concepts and actions as experts. Based on the Bulgarian case-study analysis, the authors discuss the effectiveness and current challenges of real-life implementation of EU and national policies aimed at sustainable development of peripheral regions. The rural peripheral municipality of Ivaylovgrad is an indicative case study for the ongoing processes in the peripheral regions of Bulgaria and the efforts to overcome a continuing loss of working places, services, markets and further isolation from the rest of the country since the early 1990s. The paper presents a critical view of initiatives and projects undertaken by interest and local groups in the period 2006-2010. Possible innovative approaches for regional revival are considered and conclusions are drawn about the importance of creating development strategies sensitive to the existing and emerging socio-cultural patterns.

  14. A glucose anode for enzymatic fuel cells optimized for current production under physiological conditions using a design of experiment approach.

    Kumar, Rakesh; Leech, Dónal

    2015-12-01

    This study reports a design of experiment methodology to investigate and improve the performance of glucose oxidizing enzyme electrodes. Enzyme electrodes were constructed by co-immobilization of amine-containing osmium redox complexes, multiwalled carbon nanotubes and glucose oxidase in a carboxymethyldextran matrix at graphite electrode surfaces to provide a 3-dimensional matrix for electrocatalytic oxidation of glucose. Optimization of the amount of the enzyme electrode components to produce the highest current density under pseudo-physiological conditions of 5 mM glucose in saline buffer at 37 °C was performed using response surface methodology. A statistical analysis showed that the proposed model had a good fit with the experimental results. From the validated model, the addition of multiwalled carbon nanotubes and carboxymethyldextran components was identified as major contributing factors to the improved performance. Based on the optimized amount of components, enzyme electrodes display current densities of 1.2±0.1 mA cm(-2) and 5.2±0.2 mA cm(-2) at 0.2 V vs. Ag/AgCl in buffer containing 5 mM and 100 mM glucose, respectively, largely consistent with the predicted values. This demonstrates that use of a design of experiment approach can be applied effectively and efficiently to improve the performance of enzyme electrodes as anodes for biofuel cell device development. PMID:26116416

  15. Morphological control of layered double hydroxide through a biomimetic approach using carboxylic and sulfonic acids

    Taishi Yokoi

    2015-09-01

    Full Text Available Layered double hydroxides (LDHs have intercalation properties and are used in various applications. The performances of the LDH materials can be improved by controlling crystal morphology. Morphology of inorganic crystals is controlled by organic molecules in biomineralization. Inspired by biomineralization, we investigated the effect of the addition of mono, di and triacids as morphological control agents on crystal morphology of LDH synthesized by the homogeneous precipitation method. Morphology of LDH was changed from hexagonal plate to stacked disc by addition of monoacids, namely acetic acid and methanesulfonic acid, in the reaction solution. Flower-shaped LDH crystals were formed in the presence of diacids and a triacid, namely succinic acid, 1,2-ethanedisulfonic acid and 1,2,3-propanetricarboxylic acid. We found that the morphology of the LDH crystals was controlled by the number of functional group on the morphological control agent rather than the type of functional group. These findings can contribute for the development of novel and functional LDH materials with precisely controlled morphology.

  16. The roles of long-chain polyunsaturated fatty acids in pregnancy, lactation and infancy: review of current knowledge and consensus recommendations

    Koletzko, Berthold; Lien, Eric; Agostoni, Carlo;

    2008-01-01

    This paper reviews current knowledge on the role of the long-chain polyunsaturated fatty acids (LC-PUFA), docosahexaenoic acid (DHA, C22:6n-3) and arachidonic acid (AA, 20:4n-6), in maternal and term infant nutrition as well as infant development. Consensus recommendations and practice guidelines...... consumption of oils rich in n-3 LC-PUFA during pregnancy reduces the risk for early premature birth. Pregnant and lactating women should aim to achieve an average daily intake of at least 200 mg DHA. For healthy term infants, we recommend and fully endorse breastfeeding, which supplies preformed LC-PUFA, as...... the preferred method of feeding. When breastfeeding is not possible, we recommend use of an infant formula providing DHA at levels between 0.2 and 0.5 weight percent of total fat, and with the minimum amount of AA equivalent to the contents of DHA. Dietary LC-PUFA supply should continue after the...

  17. [The current concepts on the absorption of monosaccharides, amino acids and peptides in the mammalian small intestine].

    Timofeeva, N M; Iezuitova, N N; Gromova, L V

    2000-01-01

    The review is mainly devoted to the development of ideas about absorption, or transport, of basic nutrients in the small intestine in humans and higher animal. The absorption processes have been characterized on the example of such substances, vital for organism, as carbohydrates and proteins. The review considers a molecular structure of transporters--protein molecules, which take part in a transfer of the products of lumenal and membrane digestion of carbohydrates (glucose, galactose, fructose) and proteins (amino acids, oligopeptides) across the enterocyte membranes. An information is presented about genetic disturbances of transport of certain amino acids during such diseases as Hartnup disease, cystinuria, and iminoglycineuria. PMID:11094795

  18. Lignocellulosic Biomass to Ethanol Process Design and Economics Utilizing Co-Current Dilute Acid Prehydrolysis and Enzymatic Hydrolysis Current and Futuristic Scenarios; TOPICAL

    The National Renewable Energy Laboratory (NREL) has undertaken a complete review and update of the process design and economic model for the biomass-to-ethanol enzymatic based process. The process design includes the core technologies being researched by the U.S. Department of Energy (DOE): prehydrolysis, simultaneous saccharification and co-fermentation, and cellulase enzyme production. In addition, all ancillary areas-feed handling, product recovery and purification, wastewater treatment lignin burner and boiler-turbogenerator, and utilities-are included. NREL engaged Delta-T Corporation to assist in the process design evaluation, equipment costing, and overall plant integration. The process design and costing for the lignin burner and boiler turbogenerator has been reviewed by Reaction Engineering Inc. and the wastewater treatment by Merrick and Company. An overview of both reviews is included here. The purpose of this update was to ensure that the process design and equipment costs were reasonable and consistent with good engineering practice for plants of this type using available technical data. This work has resulted in an economic model that can be used to predict the cost of producing ethanol from cellulosic biomass using this technology if a plant were to be built in the next few years. The model was also extended using technology improvements that are expected to be developed based on the current DOE research plan. Future process designs and cost estimates are given for the years 2005, 2010, and 2015

  19. Do assorted approaches aid in estimation of uronic acids? Case studies on Tinospora sinensis polysaccharides.

    Kumar, Vineet; Nagar, Shipra; Tripathi, Y C

    2014-09-01

    Polysaccharides containing uronic acids are of immense biological significance. Colorimetric methods using different chromogens have been explored for uronic acid estimation in polysaccharides but these methods counter numerous difficulties, when neutral sugars are present in substantial amount. The uronic acid content of cold water-soluble polysaccharide (CWSP) and hot water-soluble polysaccharide (HWSP) isolated from Tinospora sinensis, widely known for marked therapeutic significance has been studied. The uronic acid was quantitatively estimated by spectrophotometric methods using carbazole, 3-phenylphenol and 3,5-dimethylphenol (DMP) vis-a-vis gas-liquid chromatography (GLC) analysis. Galacturonic acid in CWSP and HWSP was estimated as 1.41% and 1.20% respectively. The findings bring to light, the efficacy of chromogens and also reveal to what extent, they could be relied upon. The results also indicated higher specificity and selectivity of DMP over carbazole and 3-phenylphenol. However, GLC analysis despite time consuming remains the finest method for precise estimation of uronic acids. Further, GLC analysis of alditol acetates indicated the monosugar composition of L-rhamnose, L-arabinose, D-mannose, D-galactose and D-glucose in molar ratio 0.178, 0.259, 0.140, 1.045 and 98.377 in CWSP and L-rhamnose, L-arabinose, D-xylose, D-mannose, D-galactose and D-glucose in molar ratio 0.608, 0.628, 0.978, 0.227, 0.111 and 97.448 in HWSP respectively. PMID:25034757

  20. Amino Acids from Icy Amines: A Radiation-Chemical Approach to Extraterrestrial Synthesis

    Dworkin, J. P.; Moore, M. H.

    2010-01-01

    Detections of amino acids in meteorites go back several decades, with at least 100 such compounds being reported for the Murchison meteorite alone. The presence of these extraterrestrial molecules raises questions as to their formation, abundance, thermal stability, racemization, and possible subsequent reactions. Although all of these topics have been studied in laboratories, such work often involves many variables and unknowns. This has led us to seek out model systems with which to uncover reaction products, test chemical predictions, and sited light on underlying reaction mechanisms. This presentation will describe one such study, focusing on amino-acid formation in ices.

  1. Features of the low-power charge controller of lead-acid current sources charged by solar batteries

    Influence of different factors on exploitations characteristics of solar photoelectric plant is investigated by field-performance data. A construction of charge controller of the lead-acid accumulator battery charging by means of solar battery is analyzed taking into account these factors. (authors)

  2. Production of phenylpyruvic acid from L-phenylalanine using an L-amino acid deaminase from Proteus mirabilis: comparison of enzymatic and whole-cell biotransformation approaches.

    Hou, Ying; Hossain, Gazi Sakir; Li, Jianghua; Shin, Hyun-Dong; Liu, Long; Du, Guocheng

    2015-10-01

    Phenylpyruvic acid (PPA) is an important organic acid that has a wide range of applications. In this study, the membrane-bound L-amino acid deaminase (L-AAD) gene from Proteus mirabilis KCTC 2566 was expressed in Escherichia coli BL21(DE3) and then the L-AAD was purified. After that, we used the purified enzyme and the recombinant E. coli whole-cell biocatalyst to produce PPA via a one-step biotransformation from L-phenylalanine. L-AAD was solubilized from the membrane and purified 52-fold with an overall yield of 13 %, which corresponded to a specific activity of 0.94 ± 0.01 μmol PPA min(-1)·mg(-1). Then, the biotransformation conditions for the pure enzyme and the whole-cell biocatalyst were optimized. The maximal production was 2.6 ± 0.1 g·L(-1) (specific activity of 1.02 ± 0.02 μmol PPA min(-1)·mg(-1) protein, 86.7 ± 5 % mass conversion rate, and 1.04 g·L(-1)·h(-1) productivity) and 3.3 ± 0.2 g L(-1) (specific activity of 0.013 ± 0.003 μmol PPA min(-1)·mg(-1) protein, 82.5 ± 4 % mass conversion rate, and 0.55 g·L(-1)·h(-1) productivity) for the pure enzyme and whole-cell biocatalyst, respectively. Comparative studies of the enzymatic and whole-cell biotransformation were performed in terms of specific activity, production, conversion, productivity, stability, need of external cofactors, and recycling. We have developed two eco-friendly and efficient approaches for PPA production. The strategy described herein may aid the biotransformational synthesis of other α-keto acids from their corresponding amino acids. PMID:26109004

  3. Detecting relationships between amylose content and amino acid contents of indica rice with conditional approach

    Chun Hai Shi; Qiong Qiong Zhu; Ke Ming Wang; Guo Ke Ge; Jian Guo Wu; Zhen Ghao Xu

    2010-04-01

    The relationship between the genetic effects of endosperm, cytoplasm and maternal plant on amylose content (AC) and amino acid contents of indica rice was studied using unconditional and conditional analysis methods. The results indicated that the protein content (PC) and brown rice weight (WBR) could significantly affect the relationships between AC and amino acid contents of rice. The phenotypic and genotypic covariances between AC and amino acid contents were most significantly negative under the interference of PC or WBR, but most of the relationships for the paired traits were not significant after excluding the influence of PC or WBR on AC. For the conditional genetic relationship analysis of different genetic systems including endosperm, cytoplasm and maternal plant, visible changes were found in many genetic correlation components between AC and amino acid content after eliminating the influences of PC, especially, for the endosperm or maternal additive effects, endosperm additive or dominance interaction effects and maternal additive interaction effects. The relationships of the paired traits conditioned on WBR were mainly controlled by the endosperm dominance or additive interaction effects.

  4. Diversity, vitality and activities of intestinal lactic acid bacteria and bifidobacteria assessed by molecular approaches

    Vaughan, E.E.; Heilig, G.H.J.; Ben-Amor, K.; Vos, de W.M.

    2005-01-01

    While lactic acid bacteria and bifidobacteria have been scientifically important for over a century, many of these are marketed today as probiotics and have become a valuable and rapidly expanding sector of the food market that is leading functional foods in many countries. The human gastro-intestin

  5. Novel approach to recover cobalt and lithium from spent lithium-ion battery using oxalic acid

    Highlights: • Short-cut recovery of cobalt and lithium was directly obtained using oxalic acid. • Short-cut recovery process was optimized for a high recovery rate. • Leaching process was controlled by chemical reaction. • Leaching order of the sampling LiCoO2 using oxalic acid was first proposed. - Abstract: With the booming of consumer electronics (CE) and electric vehicle (EV), a large number of spent lithium-ion battery (LIBs) have been generated worldwide. Resource depletion and environmental concern driven from the sustainable industry of CE and EV have motivated spent LIBs should be recovered urgently. However, the conventional process combined with leaching, precipitating, and filtering was quite complicated to recover cobalt and lithium from spent LIBs. In this work, we developed a novel recovery process, only combined with oxalic acid leaching and filtering. When the optimal parameters for leaching process is controlled at 150 min retention time, 95 °C heating temperature, 15 g L−1 solid–liquid ratio, and 400 rpm rotation rate, the recovery rate of lithium and cobalt from spent LIBs can reach about 98% and 97%, respectively. Additionally, we also tentatively discovered the leaching mechanism of lithium cobalt oxide (LiCoO2) using oxalic acid, and the leaching order of the sampling LiCoO2 of spent LIBs. All the obtained results can contribute to a short-cut and high-efficiency process of spent LIBs recycling toward a sound closed-loop cycle

  6. Raman spectroscopy of the system iron(III)-sulfuric acid-water: an approach to Tinto River's (Spain) hydrogeochemistry.

    Sobron, P; Rull, F; Sobron, F; Sanz, A; Medina, J; Nielsen, C J

    2007-12-15

    Acid mine drainage is formed when pyrite (FeS(2)) is exposed and reacts with air and water to form sulfuric acid and dissolved iron. Tinto River (Huelva, Spain) is an example of this phenomenon. In this study, Raman spectroscopy has been used to investigate the speciation of the system iron(III)-sulfuric acid-water as an approach to Tinto River's aqueous solutions. The molalities of sulfuric acid (0.09 mol/kg) and iron(III) (0.01-1.5 mol/kg) were chosen to mimic the concentration of the species in Tinto River waters. Raman spectra of the solutions reveal a strong iron(III)-sulfate inner-sphere interaction through the nu(1) sulfate band at 981 cm(-1) and its shoulder at 1005 cm(-1). Iron(III)-sulfate interaction may also be facilitated by hydrogen bonds and monitored in the Raman spectra through the symmetric stretching band of bisulfate at 1052 cm(-1) and a shoulder at 1040 cm(-1). Other bands in the low-frequency region of the Raman spectra are attributed to the hydrogen-bonded complexes formation as well. PMID:17869164

  7. Fluorescent probes for detection of picric acid explosive: A greener approach

    Green materials with advantages of low cost and high sensitivity are important from the perspective of human health, environment and homeland security. Herein, we have reported two cost effective modified biomaterials as fluorophores for detection of Picric acid in aqueous state. The biomaterials Scutellarin–Hispiduloside and Curcumin have been modified with green solvent glycerol for Picric acid detection in aqueous solution. The limit of detection for Picric acid by Scutellarin–Hispiduloside–glycerol and Curcumin–glycerol are 9.1×10−8 M and 6.03×10−8 M respectively. These luminescence based sensors have also been able to detect Picric acid in real samples with high efficiency. The fluorescence quenching efficiency of Scutellarin–Hispiduloside–glycerol has been found to be 99% while that for Curcumin–glycerol, it is 88.9% for 0.5 µM Picric acid in aqueous state. In both the cases, the quenching is governed by FRET between the fluorophore and the quencher and the FRET efficiency has been found to be 0.968 and 0.792 respectively. In addition, both the systems show excellent selectivity towards PA in presence of other nitroaromatic compounds and are also statistically accessible. The utilization of readily available cheap biomaterials without using multistep protocol for synthesis and devoid of any kind of sophisticated equipments for the processs further enhances the utility of the method. - Highlights: • Environmentally benign systems – Scutellarin, Hispiduloside and curcumin with green solvent glycerol – have been used for Picric acid sensing. • The method is simple and cost effective with a detection limit for CIG and CG found to be 9.1×10−8 M and 6.03×10−8 M of PA respectively. • Both the sensing systems were found to be highly selective for Picric acid in the presence of structurally similar compounds. • The quenching occurs by FRET between the fluorophore and the quencher and the FRET efficiency is determined. • The

  8. Fluorescent probes for detection of picric acid explosive: A greener approach

    Chakravarty, Sudesna; Gogoi, Bedanta; Sen Sarma, Neelotpal, E-mail: neelot@iasst.gov.in

    2015-09-15

    Green materials with advantages of low cost and high sensitivity are important from the perspective of human health, environment and homeland security. Herein, we have reported two cost effective modified biomaterials as fluorophores for detection of Picric acid in aqueous state. The biomaterials Scutellarin–Hispiduloside and Curcumin have been modified with green solvent glycerol for Picric acid detection in aqueous solution. The limit of detection for Picric acid by Scutellarin–Hispiduloside–glycerol and Curcumin–glycerol are 9.1×10{sup −8} M and 6.03×10{sup −8} M respectively. These luminescence based sensors have also been able to detect Picric acid in real samples with high efficiency. The fluorescence quenching efficiency of Scutellarin–Hispiduloside–glycerol has been found to be 99% while that for Curcumin–glycerol, it is 88.9% for 0.5 µM Picric acid in aqueous state. In both the cases, the quenching is governed by FRET between the fluorophore and the quencher and the FRET efficiency has been found to be 0.968 and 0.792 respectively. In addition, both the systems show excellent selectivity towards PA in presence of other nitroaromatic compounds and are also statistically accessible. The utilization of readily available cheap biomaterials without using multistep protocol for synthesis and devoid of any kind of sophisticated equipments for the processs further enhances the utility of the method. - Highlights: • Environmentally benign systems – Scutellarin, Hispiduloside and curcumin with green solvent glycerol – have been used for Picric acid sensing. • The method is simple and cost effective with a detection limit for CIG and CG found to be 9.1×10−8 M and 6.03×10−8 M of PA respectively. • Both the sensing systems were found to be highly selective for Picric acid in the presence of structurally similar compounds. • The quenching occurs by FRET between the fluorophore and the quencher and the FRET efficiency is determined

  9. High extracellular Ca2+ stimulates Ca2+-activated Cl- currents in frog parathyroid cells through the mediation of arachidonic acid cascade.

    Yukio Okada

    Full Text Available Elevation of extracellular Ca(2+ concentration induces intracellular Ca(2+ signaling in parathyroid cells. The response is due to stimulation of the phospholipase C/Ca(2+ pathways, but the direct mechanism responsible for the rise of intracellular Ca(2+ concentration has remained elusive. Here, we describe the electrophysiological property associated with intracellular Ca(2+ signaling in frog parathyroid cells and show that Ca(2+-activated Cl(- channels are activated by intracellular Ca(2+ increase through an inositol 1,4,5-trisphophate (IP(3-independent pathway. High extracellular Ca(2+ induced an outwardly-rectifying conductance in a dose-dependent manner (EC(50 ∼6 mM. The conductance was composed of an instantaneous time-independent component and a slowly activating time-dependent component and displayed a deactivating inward tail current. Extracellular Ca(2+-induced and Ca(2+ dialysis-induced currents reversed at the equilibrium potential of Cl(- and were inhibited by niflumic acid (a specific blocker of Ca(2+-activated Cl(- channel. Gramicidin-perforated whole-cell recording displayed the shift of the reversal potential in extracellular Ca(2+-induced current, suggesting the change of intracellular Cl(- concentration in a few minutes. Extracellular Ca(2+-induced currents displayed a moderate dependency on guanosine triphosphate (GTP. All blockers for phospholipase C, diacylglycerol (DAG lipase, monoacylglycerol (MAG lipase and lipoxygenase inhibited extracellular Ca(2+-induced current. IP(3 dialysis failed to induce conductance increase, but 2-arachidonoylglycerol (2-AG, arachidonic acid and 12S-hydroperoxy-5Z,8Z,10E,14Z-eicosatetraenoic acid (12(S-HPETE dialysis increased the conductance identical to extracellular Ca(2+-induced conductance. These results indicate that high extracellular Ca(2+ raises intracellular Ca(2+ concentration through the DAG lipase/lipoxygenase pathway, resulting in the activation of Cl(- conductance.

  10. Analysis of the Current Nutrient Management Practices in Semi-Arid Areas of Eastern Kenya: A Nutmon Approach

    Declining soil fertility caused mainly by continuous cultivation without adequate replenishment of nutrients, is a major factor contributing to low crop yields in the arid and semi arid areas of Kenya. Development of appropriate nutrient management strategies for suitable agricultural production in these areas is, therefore, a priority issue. in the study reported here, analyses of the current nutrient management practices were carried out using the nutrient monitoring (NUTMON) approach in order to create farm house-hold awareness on nutrient management aspects. The procedure involved participatory soil and nutrient flow maps and soil sampling at farm level. laboratory analysis of the soil samples was later carried out. Structured questionnaires were used for systematic collection of information on farm management practices in order to quantify flows of materials with emphasis on soil nutrients and cash. Results of the laboratory soil analysis were also presented to the farmers and discussed during feedback sessions. The test was carried out in three places namely, Kibwezi, Kasikeu and Kiomo. In all the three clusters, off-farm income was an important component of the total family income. Farm net cash flow was highest in Kibwezi cluster due to horticultural crop production activities. Household net cash flow was highest in Kasikeu, largely originating from off-farm income. It was concluded that NUTMON methodology appeared a suitable tool for the diagnostic of the farming system analysis and design in the arid and semi-arid lands of Kenya

  11. The impact of acid deposition and forest harvesting on lakes and their forested catchments in south central Ontario: a critical loads approach

    S. A. Watmough

    2002-01-01

    Full Text Available The impact of acid deposition and tree harvesting on three lakes and their representative sub-catchments in the Muskoka-Haliburton region of south-central Ontario was assessed using a critical loads approach. As nitrogen dynamics in forest soils are complex and poorly understood, for simplicity and to allow comparison among lakes and their catchments, CLs (A for both lakes and forest soils were calculated assuming that nitrate leaching from catchments will not change over time (i.e. a best case scenario. In addition, because soils in the region are shallow, base cation weathering rates for the representative sub-catchments were calculated for the entire soil profile and these estimates were also used to calculate critical loads for the lakes. These results were compared with critical loads obtained by the Steady State Water Chemistry (SSWC model. Using the SSWC model, critical loads for lakes were between 7 and 19 meq m-2yr-1 higher than those obtained from soil measurements. Lakes and forests are much more sensitive to acid deposition if forests are harvested, but two acid-sensitive lakes had much lower critical loads than their respective forested sub-catchments implying that acceptable acid deposition levels should be dictated by the most acid-sensitive lakes in the region. Under conditions that assume harvesting, the CL (A is exceeded at two of the three lakes and five of the six sub-catchments assessed in this study. However, sulphate export from catchments greatly exceeds input in bulk deposition and, to prevent lakes from falling below the critical chemical limit, sulphate inputs to lakes must be reduced by between 37% and 92% if forests are harvested. Similarly, sulphate leaching from forested catchments that are harvested must be reduced by between 16 and 79% to prevent the ANC of water draining the rooting zone from falling below 0 μeq l-1. These calculations assume that extremely low calcium leaching losses (9–27 μeq l-1 from

  12. A current overview of commercially available nucleic acid diagnostics approaches to detect and identify human gastroenteritis pathogens

    Kate Reddington

    2014-09-01

    The main purpose of this review is to describe a number of recently available multiparametric commercial tests, to support the rapid and accurate clinical diagnosis of human gastroenteritis. These state of the art technologies have the ability to identify a wide range of microorganisms associated with enteric gastroenteritis. Following further technological innovation and more comprehensive clinical validation studies, these NAD tests have the potential to impact on the economic burden of health care systems. These rapid NAD tests can also be used to guide improved patient therapy in a timely manner which will reduce the extent of morbidity and mortality associated with these infections globally.

  13. Probing inclusion complexes of cyclodextrins with amino acids by physicochemical approach.

    Roy, Mahendra Nath; Roy, Aditi; Saha, Subhadeep

    2016-10-20

    Formations of host-guest inclusion complexes of two natural amino acids, viz., l-Leucine and l-Isoleucine as guests with α and β-cyclodextrins have been investigated which include diverse applications in modern science such as controlled delivery in the field of pharmaceuticals, food processing etc. Surface tension and conductivity studies establish the formation of inclusion complexes with 1:1 stoichiometry. The interactions of cyclodextrins with amino acids have been supported by density, viscosity, refractive index, hydration and solvation number measurements indicating higher degree of inclusion in case of α-cyclodextrin. l-Leucine interacts more with the hydrophobic cavity of cyclodextrin than its isomer. With the help of stability constant by NMR titration, hydrophobic effect, H-bonds and structural effects the formations of inclusion complexes have been explained. PMID:27474589

  14. Weight-of-evidence approach in assessment of ecotoxicological risks of acid sulphate soils in the Baltic Sea river estuaries

    Acidity and leaching of metals from acid sulphate soils (ASSs) impair the water quality of receiving surface waters. The largest ASS areas in Europe are found in the coasts of the northern Baltic Sea. We used weight-of-evidence (WoE) approach to assess potential risks in 14 estuary sites affected by ASS in the Gulf of Finland, northern Baltic Sea. The assessment was based on exposure and effect profiles utilizing sediment and water metal concentrations and concurrent pH variation, sediment toxicity tests using the luminescent bacterium Vibrio fischeri and the midge Chironomus riparius, and the ecological status of benthic macroinvertebrate communities. Sediment metal concentrations were compared to national sediment quality criteria/guidelines, and water metal concentrations to environmental quality standards (EQSs). Hazard quotients (HQs) were established for maximum aluminium, cadmium and zinc concentrations at low pH based on applicable US EPA toxicity database. Sediment metal concentrations were clearly elevated in most of the studied estuaries. The EQS of cadmium (0.1 μg/l) was exceeded in 3 estuaries out of 14. The pH-minima were below the national threshold value (5.5) between good and satisfactory water quality in 10 estuaries. V. fischeri bioluminescence indicated toxicity of the sediments but toxic response was not observed in the C. riparius emergence test. Benthic invertebrate communities were deteriorated in 6 out of 14 sites based on the benthic invertebrate quality index. The overall ecotoxicological risk was assessed as low in five, moderate in three and high in five of the estuary sites. The risk assessment utilizing the WoE approach indicated that harmful effects of ASSs are likely to occur in the Baltic Sea river estuaries located at the ASS hotspot area. - Highlights: • Acid sulphate soils release high amounts of metals and acidity. • Metals and acidity are transported to estuary sites. • Acid sulphate soils impair the ecological status

  15. Weight-of-evidence approach in assessment of ecotoxicological risks of acid sulphate soils in the Baltic Sea river estuaries

    Wallin, Jaana, E-mail: jaana.wallin@jyu.fi [Finnish Environment Institute SYKE, Survontie 9 A, FI-40500 Jyväskylä (Finland); Karjalainen, Anna K. [Finnish Environment Institute SYKE, Survontie 9 A, FI-40500 Jyväskylä (Finland); Schultz, Eija [Finnish Environment Institute SYKE, Hakuninmaantie 6, FI-00430 Helsinki (Finland); Järvistö, Johanna; Leppänen, Matti; Vuori, Kari-Matti [Finnish Environment Institute SYKE, Survontie 9 A, FI-40500 Jyväskylä (Finland)

    2015-03-01

    Acidity and leaching of metals from acid sulphate soils (ASSs) impair the water quality of receiving surface waters. The largest ASS areas in Europe are found in the coasts of the northern Baltic Sea. We used weight-of-evidence (WoE) approach to assess potential risks in 14 estuary sites affected by ASS in the Gulf of Finland, northern Baltic Sea. The assessment was based on exposure and effect profiles utilizing sediment and water metal concentrations and concurrent pH variation, sediment toxicity tests using the luminescent bacterium Vibrio fischeri and the midge Chironomus riparius, and the ecological status of benthic macroinvertebrate communities. Sediment metal concentrations were compared to national sediment quality criteria/guidelines, and water metal concentrations to environmental quality standards (EQSs). Hazard quotients (HQs) were established for maximum aluminium, cadmium and zinc concentrations at low pH based on applicable US EPA toxicity database. Sediment metal concentrations were clearly elevated in most of the studied estuaries. The EQS of cadmium (0.1 μg/l) was exceeded in 3 estuaries out of 14. The pH-minima were below the national threshold value (5.5) between good and satisfactory water quality in 10 estuaries. V. fischeri bioluminescence indicated toxicity of the sediments but toxic response was not observed in the C. riparius emergence test. Benthic invertebrate communities were deteriorated in 6 out of 14 sites based on the benthic invertebrate quality index. The overall ecotoxicological risk was assessed as low in five, moderate in three and high in five of the estuary sites. The risk assessment utilizing the WoE approach indicated that harmful effects of ASSs are likely to occur in the Baltic Sea river estuaries located at the ASS hotspot area. - Highlights: • Acid sulphate soils release high amounts of metals and acidity. • Metals and acidity are transported to estuary sites. • Acid sulphate soils impair the ecological status

  16. Devices and approaches for generating specific high-affinity nucleic acid aptamers

    Szeto, Kylan; Craighead, Harold G.

    2014-09-01

    High-affinity and highly specific antibody proteins have played a critical role in biological imaging, medical diagnostics, and therapeutics. Recently, a new class of molecules called aptamers has emerged as an alternative to antibodies. Aptamers are short nucleic acid molecules that can be generated and synthesized in vitro to bind to virtually any target in a wide range of environments. They are, in principal, less expensive and more reproducible than antibodies, and their versatility creates possibilities for new technologies. Aptamers are generated using libraries of nucleic acid molecules with random sequences that are subjected to affinity selections for binding to specific target molecules. This is commonly done through a process called Systematic Evolution of Ligands by EXponential enrichment, in which target-bound nucleic acids are isolated from the pool, amplified to high copy numbers, and then reselected against the desired target. This iterative process is continued until the highest affinity nucleic acid sequences dominate the enriched pool. Traditional selections require a dozen or more laborious cycles to isolate strongly binding aptamers, which can take months to complete and consume large quantities of reagents. However, new devices and insights from engineering and the physical sciences have contributed to a reduction in the time and effort needed to generate aptamers. As the demand for these new molecules increases, more efficient and sensitive selection technologies will be needed. These new technologies will need to use smaller samples, exploit a wider range of chemistries and techniques for manipulating binding, and integrate and automate the selection steps. Here, we review new methods and technologies that are being developed towards this goal, and we discuss their roles in accelerating the availability of novel aptamers.

  17. Novel approach to recover cobalt and lithium from spent lithium-ion battery using oxalic acid

    Zeng, Xianlai; Li, Jinhui, E-mail: jinhui@tsinghua.edu.cn; Shen, Bingyu

    2015-09-15

    Highlights: • Short-cut recovery of cobalt and lithium was directly obtained using oxalic acid. • Short-cut recovery process was optimized for a high recovery rate. • Leaching process was controlled by chemical reaction. • Leaching order of the sampling LiCoO{sub 2} using oxalic acid was first proposed. - Abstract: With the booming of consumer electronics (CE) and electric vehicle (EV), a large number of spent lithium-ion battery (LIBs) have been generated worldwide. Resource depletion and environmental concern driven from the sustainable industry of CE and EV have motivated spent LIBs should be recovered urgently. However, the conventional process combined with leaching, precipitating, and filtering was quite complicated to recover cobalt and lithium from spent LIBs. In this work, we developed a novel recovery process, only combined with oxalic acid leaching and filtering. When the optimal parameters for leaching process is controlled at 150 min retention time, 95 °C heating temperature, 15 g L{sup −1} solid–liquid ratio, and 400 rpm rotation rate, the recovery rate of lithium and cobalt from spent LIBs can reach about 98% and 97%, respectively. Additionally, we also tentatively discovered the leaching mechanism of lithium cobalt oxide (LiCoO{sub 2}) using oxalic acid, and the leaching order of the sampling LiCoO{sub 2} of spent LIBs. All the obtained results can contribute to a short-cut and high-efficiency process of spent LIBs recycling toward a sound closed-loop cycle.

  18. A New Approach to Study Cadmium Complexes with Oxalic Acid in Soil Solution

    Jaklová Dytrtová, Jana; Jakl, M.; Šestáková, Ivana; Zins, Emilie-Laure; Schröder, Detlef; Navrátil, Tomáš

    2011-01-01

    Roč. 693, 1/2 (2011), s. 100-105. ISSN 0003-2670 R&D Projects: GA AV ČR IAA400400806 Institutional research plan: CEZ:AV0Z40550506; CEZ:AV0Z40400503 Keywords : differential pulse anodic stripping voltammetry * electrospray ionization * low-molecular-weight organic acids * mass spectrometry * willow Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 4.555, year: 2011

  19. Decomposition of environmentally persistent perfluorooctanoic acid in water by photochemical approaches.

    Hori, Hisao; Hayakawa, Etsuko; Einaga, Hisahiro; Kutsuna, Shuzo; Koike, Kazuhide; Ibusuki, Takashi; Kiatagawa, Hiroshi; Arakawa, Ryuichi

    2004-11-15

    The decomposition of persistent and bioaccumulative perfluorooctanoic acid (PFOA) in water by UV-visible light irradiation, by H202 with UV-visible light irradiation, and by a tungstic heteropolyacid photocatalyst was examined to develop a technique to counteract stationary sources of PFOA. Direct photolysis proceeded slowly to produce CO2, F-, and short-chain perfluorocarboxylic acids. Compared to the direct photolysis, H2O2 was less effective in PFOA decomposition. On the other hand, the heteropolyacid photocatalyst led to efficient PFOA decomposition and the production of F- ions and CO2. The photocatalyst also suppressed the accumulation of short-chain perfluorocarboxylic acids in the reaction solution. PFOA in the concentrations of 0.34-3.35 mM, typical of those in wastewaters after an emulsifying process in fluoropolymer manufacture, was completely decomposed by the catalyst within 24 h of irradiation from a 200-W xenon-mercury lamp, with no accompanying catalyst degradation, permitting the catalyst to be reused in consecutive runs. Gas chromatography/mass spectrometry (GC/MS) measurements showed no trace of environmentally undesirable species such as CF4, which has a very high global-warming potential. When the (initial PFOA)/(initial catalyst) molar ratio was 10: 1, the turnover number for PFOA decomposition reached 4.33 over 24 h of irradiation. PMID:15573615

  20. Exceptionally crystalline and conducting acid doped polyaniline films by level surface assisted solution casting approach

    Puthirath, Anand B.; Methattel Raman, Shijeesh; Varma, Sreekanth J.; Jayalekshmi, S.

    2016-04-01

    Emeraldine salt form of polyaniline (PANI) was synthesized by chemical oxidative polymerisation method using ammonium persulfate as oxidant. Resultant emeraldine salt form of PANI was dedoped using ammonia solution and then re-doped with camphor sulphonic acid (CSA), naphthaline sulphonic acid (NSA), hydrochloric acid (HCl), and m-cresol. Thin films of these doped PANI samples were deposited on glass substrates using solution casting method with m-cresol as solvent. A level surface was employed to get homogeneous thin films of uniform thickness. Detailed X-ray diffraction studies have shown that the films are exceptionally crystalline. The crystalline peaks observed in the XRD spectra can be indexed to simple monoclinic structure. FTIR and Raman spectroscopy studies provide convincing explanation for the exceptional crystallinity observed in these polymer films. FESEM and AFM images give better details of surface morphology of doped PANI films. The DC electrical conductivity of the samples was measured using four point probe technique. It is seen that the samples also exhibit quite high DC electrical conductivity, about 287 S/cm for CSA doped PANI, 67 S/cm for NSA doped PANI 65 S/cm for HCl doped PANI, and just below 1 S/cm for m-cresol doped PANI. Effect of using the level surface for solution casting is studied and correlated with the observed crystallinity.

  1. NSAID-associated adverse effects and acid control aids to prevent them: a review of current treatment options.

    Naesdal, Jørgen; Brown, Kurt

    2006-01-01

    NSAIDs are central to the clinical management of a wide range of conditions. However, NSAIDs in combination with gastric acid, which has been shown to play a central role in upper gastrointestinal (GI) events, can damage the gastroduodenal mucosa and result in dyspeptic symptoms and peptic lesions such as ulceration.NSAID-associated GI mucosal injury is an important clinical problem. Gastroduodenal ulcers or ulcer complications occur in up to 25% of patients receiving NSAIDs. However, these toxicities are often not preceded by indicative symptoms. Data obtained from the Arthritis, Rheumatism, and Aging Medical Information System have shown that 50-60% of NSAID-associated peptic ulcer cases can remain clinically silent and do not present until complications occur. Therefore, prophylactic treatment to prevent GI complications may be necessary in a substantial proportion of NSAID users, especially those in groups associated with a high risk of developing these complications. Use of cyclo-oxygenase (COX)-2 selective NSAIDs, also known as 'coxibs', substantially reduces the incidence of upper GI toxicities seen with non-selective NSAIDs. However, there are concerns regarding the cardiovascular safety of coxibs. For this reason, the US FDA recommends minimal use of coxibs and only when strictly necessary. Additionally, rofecoxib has been removed from the US market and sales of valdecoxib have been suspended. Furthermore, upper GI toxicities still occur in patients receiving coxibs. Therefore, cotherapies are required to prevent and/or heal upper GI effects associated with NSAID use. Effective prophylactic and treatment strategies include misoprostol, histamine H(2) receptor antagonists and proton pump inhibitors (PPIs). The key role that gastric acid plays in upper GI adverse events among NSAID users suggests that it is important to choose the most effective agent for acid control to alleviate symptoms, heal mucosal erosions and improve the reduced quality of life in

  2. Intensification of depolymerization of polyacrylic acid solution using different approaches based on ultrasound and solar irradiation with intensification studies.

    Prajapat, Amrutlal L; Gogate, Parag R

    2016-09-01

    Depolymerization of polyacrylic acid (PAA) as sodium salt has been investigated using ultrasonic and solar irradiations with process intensification studies based on combination with hydrogen peroxide (H2O2) and ozone (O3). Effect of solar intensity, ozone flow and ultrasonic power dissipation on the extent of viscosity reduction has been investigated for individual treatment approaches. The combined approaches such as US+solar, solar+O3, solar+H2O2, US+H2O2 and US+O3 have been subsequently investigated under optimum conditions and established to be more efficient as compared to individual approaches. Approach based on US (60W)+solar+H2O2 (0.01%) resulted in the maximum extent of viscosity reduction as 98.97% in 35min whereas operation of solar+H2O2 (0.01%), US (60W), H2O2 (0.3%) and solar irradiation resulted in about 98.08%, 90.13%, 8.91% and 90.77% intrinsic viscosity reduction in 60min respectively. Approach of US (60W)+solar+ozone (400mg/h flow rate) resulted in extent of viscosity reduction as 99.47% in 35min whereas only ozone (400mg/h flow rate), ozone (400mg/h flow rate)+US (60W) and ozone (400mg/h flow rate)+solar resulted in 69.04%, 98.97% and 98.51% reduction in 60min, 55min and 55min respectively. The chemical identity of the treated polymer using combined approaches was also characterized using FTIR (Fourier transform infrared) spectra and it was established that no significant structural changes were obtained during the treatment. Overall, it can be said that the combination technique based on US and solar irradiations in the presence of hydrogen peroxide is the best approach for the depolymerization of PAA solution. PMID:27150773

  3. Analysis of critical current distribution of bent Bi2223 composite tapes by unifying parameter approach and its application to the description of average critical current-bending strain relation near the average irreversible strain

    Ochiai, S; Okuda, H; Sugano, M; Hojo, M [Graduate School of Engineering, Kyoto University, Sakyo-ku, Kyoto 606-8501 (Japan); Osamura, K [Research Institute for Applied Sciences, Sakyo-ku, Kyoto 606-8202 (Japan); Kuroda, T; Itoh, K; Kitaguchi, H; Kumakura, H [National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki 305-0047 (Japan); Wada, H, E-mail: shojiro.ochiai@materials.mbox.media.kyoto-u.ac.j [Graduate School of Frontier Sciences, University of Tokyo, Kashiwanoha, Kashiwa, Chiba 277-8561 (Japan)

    2010-02-15

    When the critical current of bent Bi2223 composite tape is measured for many specimens, the critical current value is different from specimen to specimen, being distributed from low to high values. We need to characterize the distribution of critical current at various applied strains and also to predict the distribution of irreversible strain for reliability and safe design. The present work attempted to describe them from the statistical viewpoint. In the analysis, the unifying parameter approach proposed recently by the authors was employed, in which the difference in damage evolution and critical current among the specimens was correlated with the distribution of the unifying parameter that refers to the tensile damage strain of Bi2223 filaments in composite tapes. By application of this approach to the measured critical current values under various bending strains for three Bi2223 composite tapes from different suppliers (VAM1, VAM2 and VAM3 used as the common test samples in the round robin test of VAMAS/TWA16), the unifying parameters were estimated and were formulated by the Weibull distribution function. With the formulated distribution function of the unifying parameter, the distributions of the critical current at various strains, the distribution of the irreversible bending strain and the average critical current-bending strain relation near the average irreversible bending strain could be described satisfactorily.

  4. Abordagem atual dos pacientes com doença de Hodgkin Current approach to patients with Hodgkin's disease

    Nelson Spector

    2004-03-01

    Full Text Available Nos últimos anos, houve um progresso substancial na abordagem do paciente com doença de Hodgkin. Uma nova classificação histopatológica foi adotada, e fatores prognósticos reprodutíveis foram identificados. Os pacientes são tratados de acordo com o estádio clínico e, no caso de pacientes com doença localizada, também de acordo com os fatores prognósticos. Uma consistente série de estudos em pacientes com doença localizada tornou obsoleta a realização de laparotomia e a abordagem radioterápica isolada. Nos pacientes com doença avançada, o ABVD emergiu como o regime com a melhor relação risco/benefício após uma dura seqüência de comparações com o MOPP e combinações de MOPP e ABVD. Dois regimes inovadores estão em testes, o Stanford V e o BEACOPP. Entretanto, o avanço dos resultados terapêuticos depende da redução da toxicidade nos pacientes de baixo risco e da melhora do controle da doença nos pacientes de alto risco.In recent years, significant progress has been made in the approach to the patient with Hodgkin's disease. A new histopathologic classification has been adopted and reproducible prognostic factors have been recognized. Patients are treated according to their clinical stage and, in patients with early-stage disease, also according to their prognostic factors. A consistent sequence of studies in patients with early-stage disease has made laparotomy followed by radiation therapy obsolete. In patients with advanced disease, ABVD emerged as the regimen with the best risk/benefit ratio after a hard series of direct comparisons against MOPP and combinations of MOPP and ABVD. Two innovative regimens, Stanford V and BEACOPP, are currently undergoing a thorough evaluation. However, the improvement of treatment outcome is ultimately dependent on reducing the therapy-related toxicity for patients with low-risk disease, while improving disease control for patients with poor-risk disease through a risk

  5. Thermally stimulated polarization currents of pristine poly (p-hydroxybenzoic acid - co - ethylene terephthalate) polymer liquid crystals

    Yarramaneni, Sridharbabu; Anu, Sharma; Quamara, J. K.

    2016-05-01

    Thermally stimulated polarization currents (TSPC) of pristine PET/0.8PHB polymer liquid crystals have been studied at various polarizing fields ranging from 38.5 kV/cm to 153.8 kV/cm at continuous temperatures ranging from 20 °C to 250 °C. The charge transport phenomena, responsible mechanisms can be investigated by studying TSP current spectra of these polymer liquid crystals. The TSP current spectra consists of two maxima one at low temperature region and the other at high temperature region and a linear variation in the temperature region from 70°C to 190°C. The relaxation behaviour of this PLC is results from various mechanisms associated with crystalline and amorphous phases.

  6. Radiotherapy of high-grade gliomas: current standards and new concepts, innovations in imaging and radiotherapy, and new therapeutic approaches.

    Dhermain, Frederic

    2014-01-01

    The current standards in radiotherapy of high-grade gliomas (HGG) are based on anatomic imaging techniques, usually computed tomography (CT) scanning and magnetic resonance imaging (MRI). The guidelines vary depending on whether the HGG is a histological grade 3 anaplastic glioma (AG) or a grade 4 glioblastoma multiforme (GBM). For AG, T2-weighted MRI sequences plus the region of contrast enhancement in T1 are considered for the delineation of the gross tumor volume (GTV), and an isotropic expansion of 15 to 20 mm is recommended for the clinical target volume (CTV). For GBM, the Radiation Therapy Oncology Group favors a two-step technique, with an initial phase (CTV1) including any T2 hyperintensity area (edema) plus a 20 mm margin treated with up to 46 Gy in 23 fractions, followed by a reduction in CTV2 to the contrast enhancement region in T1 with an additional 25 mm margin. The European Organisation of Research and Treatment of Cancer recommends a single-phase technique with a unique GTV, which comprises the T1 contrast enhancement region plus a margin of 20 to 30 mm. A total dose of 60 Gy in 30 fractions is usually delivered for GBM, and a dose of 59.4 Gy in 33 fractions is typically given for AG. As more than 85% of HGGs recur in field, dose-escalation studies have shown that 70 to 75 Gy can be delivered in 6 weeks with relevant toxicities developing in 60 Gy. Trials delivering a SIB into a biological GTV showed the feasibility of this treatment, but the final results, in terms of clinical benefits for HGG patients, are still pending. Many issues have been identified: the variety of MRI and PET machines (and amino-acid tracers), the heterogeneity of the protocols used for image acquisition and post-treatment, the geometric distortion and the unreliable algorithms for co-registration of brain anatomy with functional maps, and the semi-quiescent but highly invasive HGG cells. These issues could be solved by the homogenization of the protocols and software

  7. Radiotherapy of high-grade gliomas: current standards and new concepts, innovations in imaging and radiotherapy, and new therapeutic approaches

    Frederic Dhermain

    2014-01-01

    Full Text Available The current standards in radiotherapy of high-grade gliomas (HGG are based on anatomic imaging techniques, usually computed tomography (CT scanning and magnetic resonance imaging (MRI. The guidelines vary depending on whether the HGG is a histological grade 3 anaplastic glioma (AG or a grade 4 glioblastoma multiforme (GBM. For AG, T2-weighted MRI sequences plus the region of contrast enhancement in T1 are considered for the delineation of the gross tumor volume (GTV, and an isotropic expansion of 15 to 20 mm is recommended for the clinical target volume (CTV. For GBM, the Radiation Therapy Oncology Group favors a two-step technique, with an initial phase (CTV1 including any T2 hyperintensity area (edema plus a 20 mm margin treated with up to 46 Gy in 23 fractions, followed by a reduction in CTV2 to the contrast enhancement region in T1 with an additional 25 mm margin. The European Organisation of Research and Treatment of Cancer recommends a single-phase technique with a unique GTV, which comprises the T1 contrast enhancement region plus a margin of 20 to 30 mm. A total dose of 60 Gy in 30 fractions is usually delivered for GBM, and a dose of 59.4 Gy in 33 fractions is typically given for AG. As more than 85% of HGGs recur in field, dose-escalation studies have shown that 70 to 75 Gy can be delivered in 6 weeks with relevant toxicities developing in 60 Gy. Trials delivering a SIB into a biological GTV showed the feasibility of this treatment, but the final results, in terms of clinical benefits for HGG patients, are still pending. Many issues have been identified: the variety of MRI and PET machines (and amino-acid tracers, the heterogeneity of the protocols used for image acquisition and post-treatment, the geometric distortion and the unreliable algorithms for co-registration of brain anatomy with functional maps, and the semi-quiescent but highly invasive HGG cells. These issues could be solved by the homogenization of the protocols and

  8. Arachidonic acid mediates muscarinic inhibition and enhancement of N-type Ca2+ current in sympathetic neurons

    Liu, Liwang; Rittenhouse, Ann R.

    2002-01-01

    N-type Ca2+ channels participate in acute activity-dependent processes such as regulation of Ca2+-activated K+ channels and in more prolonged events such as gene transcription and long-term depression. A slow postsynaptic M1 muscarinic receptor-mediated modulation of N-type current in superior cervical ganglion neurons may be important in regulating these processes. This slow pathway inhibits N-type current by using a diffusible second messenger that has remained unidentified for more than a ...

  9. Fatty Acid Patterns of Seeds of Some Salvia Species from Iran - A Chemotaxonomic Approach.

    Moazzami Farida, Seyed Hamed; Radjabian, Tayebeh; Ranjbar, Massoud; Salami, Seyed Alireza; Rahmani, Nosrat; Ghorbani, Abdolbaset

    2016-04-01

    In this study, the seed oil content and fatty acid (FA) profile of 21 populations from 16 wild Salvia species of Iran were analyzed by GC. Patterns of chemical variations of the oils among species were identified via numerical analyses and also the taxonomic status of the infrageneric grouping was outlined in the genus. Salvia species were scored based on the contents of main FAs using principal coordinate analysis (PCO). The results showed that the total oil content in the seeds varied significantly, and ranged from 6.68 to 38.53% dry weight. α-Linolenic (18:3ω3, 1.69 - 53.56%), linoleic (18:2ω6, 13.04 - 60.64%), oleic (18:1ω9, 6.15 - 27.06%), palmitic (16:0, 3.77 - 9.27%), and stearic (18:0, 1.78 - 3.05%) acid were identified as five major FAs in the oils. The amount of ω-3 and ω-6 FAs ranged between 1.90 - 53.80% and 13.46 - 60.83% of total FAs in the seed oils, respectively. The results confirmed that FA profiles were distinctive among the species and that they can be used as chemotaxonomic markers. The discrimination of Salvia species according to their botanical classification at intersectional level was supported. In general, seed oils of Salvia species were rich sources of polyunsaturated FAs, except in linoleic and α-linolenic acid, and may be valuable for food and pharmaceutical industries. PMID:26988735

  10. Integrase Inhibitor Prodrugs: Approaches to Enhancing the Anti-HIV Activity of β-Diketo Acids

    Vasu Nair; Maurice Okello

    2015-01-01

    HIV integrase, encoded at the 3′-end of the HIV pol gene, is essential for HIV replication. This enzyme catalyzes the incorporation of HIV DNA into human DNA, which represents the point of “no-return” in HIV infection. Integrase is a significant target in anti-HIV drug discovery. This review article focuses largely on the design of integrase inhibitors that are β-diketo acids constructed on pyridinone scaffolds. Methodologies for synthesis of these compounds are discussed. Integrase inhibiti...

  11. Combined monodimensional chromatographic approaches to monitor the presence of d-amino acids in cheese

    R. SARDELLA; Lisanti, A.; Marinozzi, M; Ianni, F.; Natalini, B.; Blanch, Gracia P.; Ruiz del Castillo, M. Luisa

    2013-01-01

    The presence of d-amino acids (d-AAs) as a consequence of natural or artificial interventions such as ageing, microorganism action, preservative and conservative processes (alkali or heat treatment), is a scarcely treated aspect from the scientific community. It is also fully documented that even a minor degree of racemisation on the proteins' AAs is the cause of a reduced digestion of such proteins. Besides interfering with the regular metabolism of l-AAs, d-AAs can also contribute to the de...

  12. A Greener, Efficient Approach to Michael Addition of Barbituric Acid to Nitroalkene in Aqueous Diethylamine Medium

    Hany J. Al-Najjar

    2014-01-01

    Full Text Available An efficient method for the synthesis of a variety of pyrimidine derivatives 3a–t by reaction of barbituric acids 1a,b as Michael donor with nitroalkenes 2a–k as Michael acceptor using an aqueous medium and diethylamine is described. This 1,4-addition strategy offers several advantages, such as using an economic and environmentally benign reaction media, high yields, versatility, and shorter reaction times. The synthesized compounds were identified by 1H-NMR, 13C-NMR, CHN, IR, and MS. The structure of compound 3a was further confirmed by single crystal X-ray structure determination.

  13. A greener, efficient approach to Michael addition of barbituric acid to nitroalkene in aqueous diethylamine medium.

    Al-Najjar, Hany J; Barakat, Assem; Al-Majid, Abdullah M; Mabkhot, Yahia N; Weber, Manuel; Ghabbour, Hazem A; Fun, Hoong-Kun

    2014-01-01

    An efficient method for the synthesis of a variety of pyrimidine derivatives 3a-t by reaction of barbituric acids 1a,b as Michael donor with nitroalkenes 2a-k as Michael acceptor using an aqueous medium and diethylamine is described. This 1,4-addition strategy offers several advantages, such as using an economic and environmentally benign reaction media, high yields, versatility, and shorter reaction times. The synthesized compounds were identified by 1H-NMR, 13C-NMR, CHN, IR, and MS. The structure of compound 3a was further confirmed by single crystal X-ray structure determination. PMID:24445342

  14. A Greener, Efficient Approach to Michael Addition of Barbituric Acid to Nitroalkene in Aqueous Diethylamine Medium

    Hany J. AL-Najjar; Assem Barakat; Al-Majid, Abdullah M.; Mabkhot, Yahia N.; Manuel Weber; Ghabbour, Hazem A.; Hoong-Kun Fun

    2014-01-01

    An efficient method for the synthesis of a variety of pyrimidine derivatives 3a–t by reaction of barbituric acids 1a,b as Michael donor with nitroalkenes 2a–k as Michael acceptor using an aqueous medium and diethylamine is described. This 1,4-addition strategy offers several advantages, such as using an economic and environmentally benign reaction media, high yields, versatility, and shorter reaction times. The synthesized compounds were identified by 1H-NMR, 13C-NMR, CHN, IR, and MS. The str...

  15. Current Understanding of HSP90 as a Novel Therapeutic Target: An Emerging Approach for the Treatment of Cancer.

    Haque, Absarul; Alam, Qamre; Alam, Mohammad Zubair; Azhar, Esam I; Sait, Khalid Hussain Wali; Anfinan, Nisrin; Mushtaq, Gohar; Kamal, Mohammad Amjad; Rasool, Mahmood

    2016-01-01

    Heat Shock Protein 90 (HSP90) is a ubiquitous molecular chaperone that is considered to be the most abundantly expressed protein in various human cancers such as breast, lung, colon, prostate, leukemia and skin. The master regulator, HSP90 plays a pivotal role in the conformational stabilization, maturation and activity of its various labile oncogenic client proteins such as p53, ErbB2, Bcr-Abl, Akt, Her-2, Cdk4, Cdk6, Raf-1 and v-Src in altered cells. Hence, making a guaranteed attempt to inhibit such a master regulator for cancer therapy appears to be a potential approach for combinatorial inhibition of numerous oncogenic signaling pathways simultaneously. Considerable efforts are being under way to develop novel molecular targets and its inhibitors that may block key signaling pathways involved in the process of tumorigenesis and metastasis. In this regards, HSP90 has acquired immense interest as a potent anticancer drug-target due to its key functional link with multiple signaling pathways involved in the process of cell proliferation and cell survival. Notably, geldanamycin and its derivatives (17-AAG, 17-DMAG) have shown quite encouraging results in inhibiting HSP90 function in several cancers and currently almost 17 drug candidates known to be target HSP90 are being under clinical trials either as single agents or combinatorial therapy. Hence, this review is an attempt to get new insight into novel drug target therapy by focusing on recent advances made in understanding HSP90 chaperone structure-function relationships, identification of new HSP90 client proteins and, more importantly, on the advancements of HSP90 targeted therapy based on various existing and emerging classical inhibitors. PMID:27013225

  16. Cerebellar Transcranial Direct Current Stimulation (ctDCS): A Novel Approach to Understanding Cerebellar Function in Health and Disease.

    Grimaldi, Giuliana; Argyropoulos, Georgios P; Bastian, Amy; Cortes, Mar; Davis, Nicholas J; Edwards, Dylan J; Ferrucci, Roberta; Fregni, Felipe; Galea, Joseph M; Hamada, Masahi; Manto, Mario; Miall, R Chris; Morales-Quezada, Leon; Pope, Paul A; Priori, Alberto; Rothwell, John; Tomlinson, S Paul; Celnik, Pablo

    2016-02-01

    The cerebellum is critical for both motor and cognitive control. Dysfunction of the cerebellum is a component of multiple neurological disorders. In recent years, interventions have been developed that aim to excite or inhibit the activity and function of the human cerebellum. Transcranial direct current stimulation of the cerebellum (ctDCS) promises to be a powerful tool for the modulation of cerebellar excitability. This technique has gained popularity in recent years as it can be used to investigate human cerebellar function, is easily delivered, is well tolerated, and has not shown serious adverse effects. Importantly, the ability of ctDCS to modify behavior makes it an interesting approach with a potential therapeutic role for neurological patients. Through both electrical and non-electrical effects (vascular, metabolic) ctDCS is thought to modify the activity of the cerebellum and alter the output from cerebellar nuclei. Physiological studies have shown a polarity-specific effect on the modulation of cerebellar-motor cortex connectivity, likely via cerebellar-thalamocortical pathways. Modeling studies that have assessed commonly used electrode montages have shown that the ctDCS-generated electric field reaches the human cerebellum with little diffusion to neighboring structures. The posterior and inferior parts of the cerebellum (i.e., lobules VI-VIII) seem particularly susceptible to modulation by ctDCS. Numerous studies have shown to date that ctDCS can modulate motor learning, and affect cognitive and emotional processes. Importantly, this intervention has a good safety profile; similar to when applied over cerebral areas. Thus, investigations have begun exploring ctDCS as a viable intervention for patients with neurological conditions. PMID:25406224

  17. Current concepts on the physiology and genetics of neurotransmitters-mediating enzyme-aromatic L-amino acid decarboxylase

    Two most important neurotransmitters, dopamine and serotonin are mediated by the enzyme aromatic L-amino acid decarboxylase (AADC). Because of their importance in the regulation of neuronal functions, behaviour and emotion of higher animals, many researchers are working on this enzyme to elucidate its physiological properties, structure and genetic aspects. We have discovered this enzyme in the mammalian blood, we established sensitive assay methods for the assay of the activities of this enzyme. We have made systematic studies on this enzyme in the tissues and brains of rats, and human subjects. We have found an endogenous inhibitor of this enzyme in the monkey's blood. The amino acid sequences of human AADC has been compared to rat or bovine. A full-length cDNA clone encoding human AADC has been isolated. Very recently the structure of human AADC gene including 5'-flaking region has been characterized and the transcriptional starting point has been determined. The human AADC gene assigned to chromosome 7. Up-to-date research data have shown that AADC is encoded by a single gene. Recently two patients with AADC deficiency were reported. This paper describes the systematic up-to-date review studies on AADC. (author). 62 refs, 5 figs, 8 tabs

  18. A statistical approach to the experimental design of the sulfuric acid leaching of gold-copper ore

    Mendes F.D.

    2003-01-01

    Full Text Available The high grade of copper in the Igarapé Bahia (Brazil gold-copper ore prevents the direct application of the classic cyanidation process. Copper oxides and sulfides react with cyanides in solution, causing a high consumption of leach reagent and thereby raising processing costs and decreasing recovery of gold. Studies have showm that a feasible route for this ore would be a pretreatment for copper minerals removal prior to the cyanidation stage. The goal of this experimental work was to study the experimental conditions required for copper removal from Igarapé Bahia gold-copper ore by sulfuric acid leaching by applying a statistical approach to the experimental design. By using the Plackett Burman method, it was possible to select the variables that had the largest influence on the percentage of copper extracted at the sulfuric acid leaching stage. These were temperature of leach solution, stirring speed, concentration of sulfuric acid in the leach solution and particle size of the ore. The influence of the individual effects of these variables and their interactions on the experimental response were analyzed by applying the replicated full factorial design method. Finally, the selected variables were optimized by the ascending path statistical method, which determined the best experimental conditions for leaching to achieve the highest percentage of copper extracted. Using the optimized conditions, the best leaching results showed a copper extraction of 75.5%.

  19. VCD study of nucleic acid interaction with metal ions and drugs. Experimental and theoretical approaches

    Andrushchenko, V.; Bouř, Petr; Wieser, H.

    Budapest : Eötvös Loránd University, 2003. s. 55. [International Conference on Circular Dichroism /9./. 31.08.2003-04.09.2003, Budapest] Institutional research plan: CEZ:AV0Z4055905 Keywords : VCD * theoretical approaches Subject RIV: CC - Organic Chemistry

  20. Fed-batch Fermentation of Lactic Acid Bacteria to Improve Biomass Production: A Theoretical Approach

    Beng Lee, Boon; Tham, Heng Jin; Chan, Eng Seng

    Recently, fed-batch fermentation has been introduced in an increasing number of fermentation processes. Previous researches showed that fed-batch fermentation can increase the biomass yield of many strains. Improvement of the biomass yield is interested because biomass from lactic acid bacteria (LAB) fermentation is widely used in food and pharmaceutical industry. The aim of this research is to study the ability and feasibility of fed-batch fermentation to improve biomass production of LAB. Appropriate model has been selected from literature. Monod equation described the substrate limitation of LAB and the product inhibition of LAB follows a non-competitive model. Furthermore, the lactic acid production follows Luedeking and Piret model. Then the models are applied to simulate the fermentation of batch and fed-batch cultures by using MATLAB. From the results of simulation, fed-batch fermentation showed that substrate limitation and substrate inhibition can be avoided. Besides that, the variable volume fed-batch fermentation also showed that product inhibition can be eliminated by diluting the product concentration with added fresh feed. However, it was found that fed-batch fermentation is not economically feasible because large amount of substrate is required to reduce the product inhibition effect. Therefore, fed-batch fermentation plays more importance role if the fermentation strain has high Ks value or low Kp value.

  1. Novel approach to recover cobalt and lithium from spent lithium-ion battery using oxalic acid.

    Zeng, Xianlai; Li, Jinhui; Shen, Bingyu

    2015-09-15

    With the booming of consumer electronics (CE) and electric vehicle (EV), a large number of spent lithium-ion battery (LIBs) have been generated worldwide. Resource depletion and environmental concern driven from the sustainable industry of CE and EV have motivated spent LIBs should be recovered urgently. However, the conventional process combined with leaching, precipitating, and filtering was quite complicated to recover cobalt and lithium from spent LIBs. In this work, we developed a novel recovery process, only combined with oxalic acid leaching and filtering. When the optimal parameters for leaching process is controlled at 150 min retention time, 95 °C heating temperature, 15 g L(-1) solid-liquid ratio, and 400 rpm rotation rate, the recovery rate of lithium and cobalt from spent LIBs can reach about 98% and 97%, respectively. Additionally, we also tentatively discovered the leaching mechanism of lithium cobalt oxide (LiCoO2) using oxalic acid, and the leaching order of the sampling LiCoO2 of spent LIBs. All the obtained results can contribute to a short-cut and high-efficiency process of spent LIBs recycling toward a sound closed-loop cycle. PMID:25897692

  2. Trophic relationships in an estuarine environment: A quantitative fatty acid analysis signature approach

    Magnone, Larisa; Bessonart, Martin; Gadea, Juan; Salhi, María

    2015-12-01

    In order to better understand the functioning of aquatic environments, it is necessary to obtain accurate diet estimations in food webs. Their description should incorporate information about energy flow and the relative importance of trophic pathways. Fatty acids have been extensively used in qualitative studies on trophic relationships in food webs. Recently a new method to estimate quantitatively single predator diet has been developed. In this study, a model of aquatic food web through quantitative fatty acid signature analysis was generated to identify the trophic interactions among the species in the Rocha Lagoon. The biological sampling over two consecutive annual periods was comprehensive enough to identify all functional groups in the aquatic food web (except birds and mammals). Heleobia australis seemed to play a central role in this estuarine ecosystem. As both, a grazer and a prey to several other species, probably H. australis is transferring a great amount of energy to upper trophic levels. Most of the species at Rocha Lagoon have a wide range of prey items in their diet reflecting a complex food web, which is characteristic of extremely dynamic environment as estuarine ecosystems. QFASA is a model in tracing and quantitative estimate trophic pathways among species in an estuarine food web. The results obtained in the present work are a valuable contribution in the understanding of trophic relationships in Rocha Lagoon.

  3. Integrase Inhibitor Prodrugs: Approaches to Enhancing the Anti-HIV Activity of β-Diketo Acids

    Vasu Nair

    2015-07-01

    Full Text Available HIV integrase, encoded at the 3′-end of the HIV pol gene, is essential for HIV replication. This enzyme catalyzes the incorporation of HIV DNA into human DNA, which represents the point of “no-return” in HIV infection. Integrase is a significant target in anti-HIV drug discovery. This review article focuses largely on the design of integrase inhibitors that are β-diketo acids constructed on pyridinone scaffolds. Methodologies for synthesis of these compounds are discussed. Integrase inhibition data for the strand transfer (ST step are compared with in vitro anti-HIV data. The review also examines the issue of the lack of correlation between the ST enzymology data and anti-HIV assay results. Because this disconnect appeared to be a problem associated with permeability, prodrugs of these inhibitors were designed and synthesized. Prodrugs dramatically improved the anti-HIV activity data. For example, for compound, 96, the anti-HIV activity (EC50 improved from 500 nM for this diketo acid to 9 nM for its prodrug 116. In addition, there was excellent correlation between the IC50 and IC90 ST enzymology data for 96 (6 nM and 97 nM, respectively and the EC50 and EC90 anti-HIV data for its prodrug 116 (9 nM and 94 nM, respectively. Finally, it was confirmed that the prodrug 116 was rapidly hydrolyzed in cells to the active compound 96.

  4. Integrase Inhibitor Prodrugs: Approaches to Enhancing the Anti-HIV Activity of β-Diketo Acids.

    Nair, Vasu; Okello, Maurice

    2015-01-01

    HIV integrase, encoded at the 3'-end of the HIV pol gene, is essential for HIV replication. This enzyme catalyzes the incorporation of HIV DNA into human DNA, which represents the point of "no-return" in HIV infection. Integrase is a significant target in anti-HIV drug discovery. This review article focuses largely on the design of integrase inhibitors that are β-diketo acids constructed on pyridinone scaffolds. Methodologies for synthesis of these compounds are discussed. Integrase inhibition data for the strand transfer (ST) step are compared with in vitro anti-HIV data. The review also examines the issue of the lack of correlation between the ST enzymology data and anti-HIV assay results. Because this disconnect appeared to be a problem associated with permeability, prodrugs of these inhibitors were designed and synthesized. Prodrugs dramatically improved the anti-HIV activity data. For example, for compound, 96, the anti-HIV activity (EC50) improved from 500 nM for this diketo acid to 9 nM for its prodrug 116. In addition, there was excellent correlation between the IC50 and IC90 ST enzymology data for 96 (6 nM and 97 nM, respectively) and the EC50 and EC90 anti-HIV data for its prodrug 116 (9 nM and 94 nM, respectively). Finally, it was confirmed that the prodrug 116 was rapidly hydrolyzed in cells to the active compound 96. PMID:26184144

  5. The development of an approach to assess critical loads of acidity for woodland habitats in Great Britain

    S. J. Langan

    2004-01-01

    Full Text Available Alongside other countries that are signatories to the UNECE Convention Long Range Transboundary on Air Pollution, the UK is committed to reducing the impact of air pollution on the environment. To advise and guide this policy in relation to atmospheric emissions of sulphur and nitrogen, a critical load approach has been developed. To assess the potential impact of these pollutants on woodland habitats a steady state, simple mass balance model has been parameterised. For mineral soils, a Ca:Al ratio in soil solution has been used as the critical load indicator for potential damage. For peat and organic soils critical loads have been set according to a pH criterion. Together these approaches have been used with national datasets to examine the potential scale of acidification in woodland habitats across the UK. The results can be mapped to show the spatial variability in critical loads of the three principal woodland habitat types (managed coniferous, managed broadleaved/ mixed woodland and unmanaged woodland. The results suggest that there is a wide range of critical loads. The most sensitive (lowest critical loads are associated with managed coniferous followed by unmanaged woodland on peat soils. Calculations indicate that at steady state, acid deposition inputs reported for 1995–1997 result in a large proportion of all the woodland habitats identified receiving deposition loads in excess of their critical load; i.e. critical loads are exceeded. These are discussed in relation to future modelled depositions for 2010. Whilst significant widespread negative impacts of such deposition on UK woodland habitats have not been reported, the work serves to illustrate that if acid deposition inputs were maintained and projected emissions reductions not achieved, the long-term sustainability of large areas of woodland in the UK could be compromised. Keywords: critical loads, acid deposition, acidification, woodland, simple mass balance model

  6. Mass Transfer and Chemical Reaction Approach of the Kinetics of the Acetylation of Gadung Flour using Glacial Acetic Acid

    Andri Cahyo Kumoro

    2015-03-01

    Full Text Available Acetylation is one of the common methods of modifying starch properties by introducing acetil (CH3CO groups to starch molecules at low temperatures. While most acetylation is conducted using starch as anhidroglucose source and acetic anhydride or vinyl acetate as nucleophilic agents, this work employ reactants, namely flour and glacial acetic acid. The purpose of this work are to study the effect of pH reaction and GAA/GF mass ratio on the rate of acetylation reaction and to determine its rate constants. The acetylation of gadung flour with glacial acetic acid in the presence of sodium hydroxide as a homogenous catalyst was studied at ambient temperature with pH ranging from 8-10 and different mass ratio of acetic acid : gadung flour (1:3; 1:4; and 1:5. It was found that increasing pH, lead to increase the degree of substitution, while increasing GAA/GF mass ratio caused such decreases in the degree of substitution, due to the hydrolysis of the acetylated starch. The desired starch acetylation reaction is accompanied by undesirable hydrolysis reaction of the acetylated starch after 40-50 minutes reaction time. Investigation of kinetics of the reaction observed that the value of mass transfer rate constant (Kcs is smaller than the surface reaction rate constant (k. Thus, it can be concluded that rate controlling step is mass transfer.  © 2015 BCREC UNDIP. All rights reservedReceived: 7th August 2014; Revised: 8th September 2014; Accepted: 14th September 2014How to Cite: Kumoro, A.C., Amelia, R. (2015. Mass Transfer and Chemical Reaction Approach of the Kinetics of the Acetylation of Gadung Flour using Glacial Acetic Acid. Bulletin of Chemical Reaction Engineering & Catalysis, 10 (1: 30-37. (doi:10.9767/bcrec.10.1.7181.30-37Permalink/DOI: http://dx.doi.org/10.9767/bcrec.10.1.7181.30-37

  7. Amino acid sequence diversity of the major human papillomavirus capsid protein: Implications for current and next generation vaccines ☆

    Ahmed, Amina I.; Bissett, Sara L; Beddows, Simon

    2013-01-01

    Despite the fidelity of host cell polymerases, the human papillomavirus (HPV) displays a degree of genomic polymorphism resulting in distinct genotypes and intra-type variants. The current HPV vaccines target the most prevalent genotypes associated with cervical cancer (HPV16/18) and genital warts (HPV6/11). Although these vaccines confer some measure of cross-protection, a multivalent HPV vaccine is in the pipeline that aims to broaden vaccine protection against other cervical cancer-associa...

  8. A new amino acid mixture permits new approaches to the treatment of phenylketonuria.

    Buist, N R; Prince, A P; Huntington, K L; Tuerck, J M; Waggoner, D D

    1994-12-01

    A new amino acid mixture for incorporation into medical foods for the treatment of hyperphenylalaninemia has been tested in a regular clinic. The mix is designed to be as unobtrusive as possible, consistent with good nutrition. After more than 1 year of trial as a beverage, we have shown that it is safe and well tolerated but that plasma phenylalanine is no better controlled than with some other products. The mix can be incorporated into a large number of different foods without affecting the taste. Occult monitoring of the quantity of medical foods purchased compared with the amounts reported to be consumed in diet histories provides an excellent way to monitor dietary compliance. PMID:7766965

  9. Synthesis of nucleic acid methylphosphonates via the 1-hydroxybenzotriazole phosphotriester approach.

    Marugg, J E; de Vroom, E; Dreef, C E; Tromp, M; van der Marel, G A; van Boom, J H

    1986-01-01

    Dinucleoside methylphosphonates can easily be prepared starting from properly protected d-nucleosides and the bifunctional phosphorylating reagent methyl-O,O-bis(1-benzotriazolyl)phosphate. Separation of the diastereoisomers of 5'-DMTR-d-Ap(Me)T-3'-lev affords optically pure dinucleoside methylphosphonates which, after removal of the 3'-levulinoyl group, have been used for the synthesis of the two optically pure diastereoisomers of the hexamer d-CpGpAp(Me)TpCpG. Further, a one-pot procedure for the preparation of uridine-3',5'-cyclic methylphosphonate will be described. We also found that 3',5'-methylphosphonate linkages in RNA are not stable towards mild acid treatment. PMID:3457366

  10. The influence of 2,3-dihydroxybenzaldehyde thiosemicarbazone on catalytic currents in the system molybdenum(VI) - potassium chlorate in acid sulfate solutions

    The polarographic catalytic current in acid solutions of Mo(VI), 2,3-dihydroxybenzaldehyde thiosemicarbazone (TSC 2,3-DHBA) and chlorate ions has been investigated. The scheme of reactions, taking place in the solutions and on the electrode, has been proposed. The increase of the catalytic current is explained by the formation of an active intermediate complex [Mo(V) TSC 2,3-DHBA (ClO-3)]. The rate constant of this complex formation K = 2.56x106 mol-1 dm3 s-1, the activation energy Ea = 15.9 kcal x mol-1 and the reaction activation entropy ΔSa≠ = -23.5 e.u. have been calculated. (authors)

  11. THE INFLUENCE OF THIOSEMICARBAZONE 2,3-DIHYDROXYBENZALDEHYDE ON CATALYTIC CURRENTS IN THE SYSTEM MOLYBDENUM (VI – POTASSIUM CHLORATE IN ACID SULFATE SOLUTIONS

    Ludmila Chiriac

    2011-06-01

    Full Text Available The polarographic catalytic current in acid solutions of Mo(VI, thiosemicarbazone 2,3-dihydroxybenzaldehyde (TSC 2,3-DHBA and chlorate ions has been investigated. The scheme of reactions, taking place in the solutions and on the electrode, has been proposed. The increase of the catalytic current is explained by the formation of an active intermediate complex [Mo(V×TSC 2,3-DHBA (ClO-3]. The rate constant of this complex formation K = 2.56 × 106 mol-1×dm3×s-1, the activation energy Ea = 15.9 kcal×mol-1 and the reaction activation entropy ∆Sa¹ = -23.5 e.u. have been calculated.

  12. Current Review of Genetically Modified Lactic Acid Bacteria for the Prevention and Treatment of Colitis Using Murine Models.

    de Moreno de LeBlanc, Alejandra; Del Carmen, Silvina; Chatel, Jean-Marc; Miyoshi, Anderson; Azevedo, Vasco; Langella, Philippe; Bermúdez-Humarán, Luis G; LeBlanc, Jean Guy

    2015-01-01

    Inflammatory Bowel Diseases (IBD) are disorders of the gastrointestinal tract characterized by recurrent inflammation that requires lifelong treatments. Probiotic microorganisms appear as an alternative for these patients; however, probiotic characteristics are strain dependent and each probiotic needs to be tested to understand the underlining mechanisms involved in their beneficial properties. Genetic modification of lactic acid bacteria (LAB) was also described as a tool for new IBD treatments. The first part of this review shows different genetically modified LAB (GM-LAB) described for IBD treatment since 2000. Then, the two principally studied strategies are discussed (i) GM-LAB producing antioxidant enzymes and (ii) GM-LAB producing the anti-inflammatory cytokine IL-10. Different delivery systems, including protein delivery and DNA delivery, will also be discussed. Studies show the efficacy of GM-LAB (using different expression systems) for the prevention and treatment of IBD, highlighting the importance of the bacterial strain selection (with anti-inflammatory innate properties) as a promising alternative. These microorganisms could be used in the near future for the development of therapeutic products with anti-inflammatory properties that can improve the quality of life of IBD patients. PMID:26064086

  13. Comparison of different approaches for lifetime prediction of electrochemical systems - Using lead-acid batteries as example

    Sauer, Dirk Uwe [Electrochemical Energy Conversion and Storage Systems Group, Institute for Power Electronics and Electrical Drives (ISEA), RWTH Aachen University, Jaegerstrasse 17/19, D-52066 Aachen (Germany); Wenzl, Heinz [Electrical Energy Storage Group, Institute of Electrical Power Engineering, Clausthal University of Technology and Beratung fuer Batterien und Energietechnik, Am Bergwaeldchen 27, D-37520 Osterode (Germany)

    2008-02-01

    Different approaches for lifetime prediction for electrochemical energy storage devices are discussed with respect to their general concepts. Examples for their implementation and advantages and disadvantages are given. The models are based on: (a) physical and chemical processes and their interaction as regards ageing effects; (b) weighting of the Ah throughput whenever the operating conditions deviate from the standard conditions used for determining the lifetime under laboratory conditions; (c) an event-oriented concept from mechanical engineering (Woehler curves) which is based on a pattern recognition approach to identify severe operating conditions. Examples and details are explained for lead-acid batteries. The approaches can be applied to other electrochemical technologies including fuel cells. However, it is beyond the scope of this paper, to describe the models in all mathematical details. The models are used in system design and identification of appropriate operating strategies and therefore they must have high computational speed to allow for a comparison of a large number of system variations. (author)

  14. Photodynamic therapy (PDT) and photodiagnosis (PD) using endogenous photosensitization induced by 5-aminolevulinic acid (ALA): current clinical and development status

    Marcus, Stuart L.; Sobel, Russel S.; Golub, Allyn L.; Carroll, Ronald L.; Lundahl, Scott L.; Shulman, D. Geoffrey

    1996-04-01

    Exogenous provision of ALA to many tissues results in the accumulation of sufficient quantities of the endogenous photosensitizer protoporphyrin IX, (PpIX), to produce a photodynamic effect. Therefore, ALA may be considered the only current PDT agent in clinical development which is a biochemical precursor of a photosensitizer. Topical ALA application, followed by exposure to activating light (ALA PDT), has been reported effective for the treatment of a variety of dermatologic diseases including cutaneous T-cell lymphoma, superficial basal cell carcinoma, Bowen's disease, and actinic (solar) keratoses, and is also being examined for treatment of acne and hirsutism. PpIX induced by ALA application also may serve as a fluorescence detection marker for photodiagnosis (PD) of malignant and pre- malignant conditions of the urinary bladder and other organs. Local internal application of ALA has also been used for selective endometrial ablation in animal model systems and is beginning to be examined in human clinical studies. Systemic, oral administration of ALA has been used for ALA PDT of superficial head and neck cancer, various gastrointestinal cancers, and the condition known as Barrett's esophagus. This brief paper reviews the current clinical and development status of ALA PDT.

  15. An Approach to More Accurate Model Systems for Purple Acid Phosphatases (PAPs).

    Bernhardt, Paul V; Bosch, Simone; Comba, Peter; Gahan, Lawrence R; Hanson, Graeme R; Mereacre, Valeriu; Noble, Christopher J; Powell, Annie K; Schenk, Gerhard; Wadepohl, Hubert

    2015-08-01

    The active site of mammalian purple acid phosphatases (PAPs) have a dinuclear iron site in two accessible oxidation states (Fe(III)2 and Fe(III)Fe(II)), and the heterovalent is the active form, involved in the regulation of phosphate and phosphorylated metabolite levels in a wide range of organisms. Therefore, two sites with different coordination geometries to stabilize the heterovalent active form and, in addition, with hydrogen bond donors to enable the fixation of the substrate and release of the product, are believed to be required for catalytically competent model systems. Two ligands and their dinuclear iron complexes have been studied in detail. The solid-state structures and properties, studied by X-ray crystallography, magnetism, and Mössbauer spectroscopy, and the solution structural and electronic properties, investigated by mass spectrometry, electronic, nuclear magnetic resonance (NMR), electron paramagnetic resonance (EPR), and Mössbauer spectroscopies and electrochemistry, are discussed in detail in order to understand the structures and relative stabilities in solution. In particular, with one of the ligands, a heterovalent Fe(III)Fe(II) species has been produced by chemical oxidation of the Fe(II)2 precursor. The phosphatase reactivities of the complexes, in particular, also of the heterovalent complex, are reported. These studies include pH-dependent as well as substrate concentration dependent studies, leading to pH profiles, catalytic efficiencies and turnover numbers, and indicate that the heterovalent diiron complex discussed here is an accurate PAP model system. PMID:26196255

  16. Using physical approaches for the attenuation of lactic acid bacteria in an organic rice beverage.

    Bevilacqua, Antonio; Casanova, Francesco Pio; Petruzzi, Leonardo; Sinigaglia, Milena; Corbo, Maria Rosaria

    2016-02-01

    A wild strain of Lactobacillus plantarum, isolated from an Italian sourdough, was inoculated in an organic rice drink; however, it caused a strong acidification. Thus, it was preliminary processed through homogenization (single or multiple passes) or sonication (US) and then inoculated in the beverage. The samples were stored at 4 °C and analyzed to assess pH, production of lactic acid, viable count and sensory scores. A US-2-step process (power, 80%) could control acidification; viability and sensory traits were never affected by sonication. This result was confirmed on two commercial probiotics (Lactobacillus casei LC01 and Bifidobacterium animalis subsp. lactis Bb12). In the 2nd step samples inoculated with attenuated strains were also stored under thermal abuse conditions (25 or 37 °C for 4 or 24 h, then at 4 °C) and the results showed that US could control acidification for a short thermal abuse. Finally, US-attenuated starter cultures were inoculated in the rice drink containing β-glucans as healthy compounds; the targets did not cause any significant change of prebiotic. PMID:26678123

  17. Acidity of HOCH, HSCN, HNCO, HNCS: a treatment from the viewpoint of ab initio approach

    ALEXEI N. PANKRATOV

    2005-10-01

    Full Text Available The electronic structures of the molecules HOCN, HSCN, HNCO, HNCS and the anions [OCN]-, [SCN]- have been investigated ab initio at the RHF/6-31G(d, RHF/6-31G(d,p, MP2/6-31G(d//RHF/6-31G(d and MP2/6-31G(d,p//RHF/6-31G(d,p theory levels. The thermodynamic stability of the HNCO and HNCS molecules was shown to be higher than that of the HOCH and HSCN molecules, respectively.The following series of the alteration of the protolytes strength HSCN > HOCH, HNCS > HNCO, HOCN > HNCO, HSCN > HNCS was substantiated. The computations taking into account the electronic correlation (MP2/6-31G(d//RHF/6-31G(d and MP2/6-31G(d,p//RHF/6-31G(d,p reflect the general sequence of change in the proton-donor properties: HSCN > HOCN > HNCS > HNCO, coinciding with the order of descending hydrophobicity of the compounds. The comparative proton-donor ability of the above acids in aqueous solutions is determined basically from the electronic structure and size of their molecules and anions [OCN]-, [SCN]-, but not on medium effects.

  18. An Efficient approach for Shielding Effect of the Grounding Electrodes under Impulse-Current Voltage based on MATLAB

    Kalyani Pole

    2012-06-01

    Full Text Available The lightning current waveform has a major influence on the dynamic performance of ground electrodes. While high lightning current intensity improves the dynamic grounding performance due to ionization of the soil, very fast fronted pulses might worsen the performance in case of inductive behaviour. The previous analysis has often been based on quasistatic approximation that is not applicable to very fast fronted pulses. Previous Research focused on analyzing the impulse current dispersal regularity of different branches when injecting at one point. Comparing with the leakage current distribution of a single ground electrode, it is found that the leakage currents along the branches increase with the distance to the current feed point, and the more conductors near the injection point, the more uneven the leakage current distribution is. In this paper by simulation result we indicate that shielding effect should be taken into account when analyzing the impulse characteristics of grounding electrodes. Based on the simulation results, new empirical formulas applicable for slow and very fast fronted lightning current pulses are proposed. The effects of the ionization of the soil are disregarded; therefore, the new formulas are applicable for a conservative estimate of the upper bound of the impulse impedance of ground electrodes. In this paper we also analyze and compare by the MATLAB. We also provide dynamic behavior of ground electrodes.

  19. Current-induced spin polarization on a Pt surface: A new approach using spin-polarized positron annihilation spectroscopy

    Transversely spin-polarized positrons were injected near Pt and Au surfaces under an applied electric current. The three-photon annihilation of spin-triplet positronium, which was emitted from the surfaces into vacuum, was observed. When the positron spin polarization was perpendicular to the current direction, the maximum asymmetry of the three-photon annihilation intensity was observed upon current reversal for the Pt surfaces, whereas it was significantly reduced for the Au surface. The experimental results suggest that electrons near the Pt surfaces were in-plane and transversely spin-polarized with respect to the direction of the electric current. The maximum electron spin polarization was estimated to be more than 0.01 (1%). - Highlights: • Annihilation probability of positronium emitted from the Pt surface into the vacuum under direct current exhibited asymmetry upon current reversal. • The maximum asymmetry appeared when positron spin polarization and the direct current were perpendicular to each other. • Electrons near the Pt surfaces were in-plane and transversely spin-polarized with respect to the direction of the electric current. • Spin-polarized positronium annihilation provides a unique tool for investigating spin polarization on metal surfaces

  20. Short circuit current calculation for wind turbines with doubly-fed induction generator (DFIG) system. Problems and solution approaches

    Dinkhauser, Vincenz; Cai, Lijun [REpower SE, Osterroenfeld (Germany); Bolik, Sigrid [REpower UK Ltd., Edinburgh (United Kingdom)

    2011-07-01

    This paper evaluates the measured short circuit currents of the DFIG system and its expected machine short circuit behavior defined by the standard IEC 60909. As the DFIG system has a different short circuit behavior compared to the synchronous generator, a method for the evaluation of DFIG short circuit currents based on measurement results will be derived in this paper. (orig.)

  1. Novel approaches to tumor imaging in mice: pre targeting with radiolabeled peptide nucleic acid

    Full text.Since targeting of tumour by conventional methods is not consistently favorable, we have considered pre targeting with separate administrations of anti tumour antibody and radiolabel. As an alternative to streptavidin and biotin for this application, we earlier considered single stranded peptide nucleic acid (PNA) bound to an irrelevant protein administered first and allowed to diffuse non specifically into tumour. This was followed later by the administration of 99 m Tc labeled complementary PNA. We now report on the first studies with PNA conjugated anti tumour antibody to allow specific binding. PNA was conjugated to the NRLU-10 IgG antibody while the complementary PNA (amine derivatized) was labeled with ((m Tc using MAG3. LS174T tumour-bearing nude mice received IV 200 ug of the PNA-antibody conjugate and 20 h later, received IV 100 ug (130 uCl) of 99m Tc- complementary PNA. Animals were imaged and sacrificed 5 h later. Because of rapid clearance, at sacrifice all tissue levels of 99 m Tc were low, the highest being kidneys at about 4%ID/gm. Tumour uptake was 0.55%ID/gm for the study animals vs. 0. 13 for controls and tumour/muscle ratios were 9.8 vs. 3.6 respectively. These values represent a 2.5-fold improvement in localization over the nonspecific study. The whole body images also reflected the superior targeting of study vs. control animals. We conclude that single-stranded PNAs should be a useful alternative to streptavidin and biotin for pre targeting studies

  2. Antioxidant Activity of Caffeic Acid against Iron-Induced Free Radical Generation--A Chemical Approach.

    Thiago C Genaro-Mattos

    Full Text Available Caffeic acid (CA is a phenolic compound widely found in coffee beans with known beneficial effects in vivo. Many studies showed that CA has anti-inflammatory, anti-mutagenic, antibacterial and anti-carcinogenic properties, which could be linked to its antioxidant activity. Taking in consideration the reported in vitro antioxidant mechanism of other polyphenols, our working hypothesis was that the CA antioxidant activity could be related to its metal-chelating property. With that in mind, we sought to investigate the chemical antioxidant mechanism of CA against in vitro iron-induced oxidative damage under different assay conditions. CA was able to prevent hydroxyl radical formation promoted by the classical Fenton reaction, as determined by 2-deoxyribose (2-DR oxidative degradation and DMPO hydroxylation. In addition to its ability to prevent hydroxyl radical formation, CA had a great inhibition of membrane lipid peroxidation. In the lipid peroxidation assays CA acted as both metal-chelator and as hydrogen donor, preventing the deleterious action promoted by lipid-derived peroxyl and alkoxyl radicals. Our results indicate that the observed antioxidant effects were mostly due to the formation of iron-CA complexes, which are able to prevent 2-DR oxidation and DMPO hydroxylation. Noteworthy, the formation of iron-CA complexes and prevention of oxidative damage was directly related to the pH of the medium, showing better antioxidant activity at higher pH values. Moreover, in the presence of lipid membranes the antioxidant potency of CA was much higher, indicating its enhanced effectiveness in a hydrophobic environment. Overall, our results show that CA acts as an antioxidant through an iron chelating mechanism, preventing the formation of free hydroxyl radicals and, therefore, inhibiting Fenton-induced oxidative damage. The chemical properties of CA described here--in association with its reported signaling effects--could be an explanation to its

  3. Aspectos atuais sobre aminoácidos de cadeia ramificada e exercício físico Current aspects of branched chain amino acid and exercise

    Marcelo Macedo Rogero

    2008-12-01

    modulation of the immune response, in performance enhancement of individuals who work out in hot environments, and in avoiding muscle lesion. This review approaches all aspects of the metabolism of and supplementation with branched chain amino acids in physical exercise.

  4. Synthesis of Framework Isomer MOFs Containing Zinc and 4-Tetrazolyl Benzenecarboxylic Acid via a Structure Directing Solvothermal Approach

    Carlos Ordonez

    2015-04-01

    Full Text Available The solvothermal synthesis of framework isomers was carried out using the hybrid carboxylate and tetrazolate functional ligand, 4-tetrazolyl benzenecarboxylic acid (H2TBC, TBC = 4-tetrazolyl benzenecarboxylate and zinc. H2TBC was also synthesized with the solvothermal approach, and is referred herein as structure 1. Using single-crystal X-ray diffraction, we found that the tetrazolate groups of TBC show an unusual “opposite-on” coordination mode with zinc. Three previously characterized metal-organic frameworks (MOFs were obtained by systematically changing the solvents of the H2TBC-Zn reaction, (1 ZnTBC, 2, which has a non-porous structure; (2 Zn2(TBC2(H2O, 3, which has an amphiphilic pore structure and (3 Zn2(TBC2{guest}, 4, which is porous and has channels containing uncoordinated N heteroatoms. Fluorescence spectra of 4 reveal a strong blue emission mainly from the TBC ligands.

  5. An Additional Approach to Model Current Followers and Amplifiers with Electronically Controllable Parameters from Commercially Available ICs

    Sotner, R.; Kartci, A.; Jerabek, J.; Herencsar, N.; Dostal, T.; Vrba, K.

    2012-12-01

    Several behavioral models of current active elements for experimental purposes are introduced in this paper. These models are based on commercially available devices. They are suitable for experimental tests of current- and mixed-mode filters, oscillators, and other circuits (employing current-mode active elements) frequently used in analog signal processing without necessity of onchip fabrication of proper active element. Several methods of electronic control of intrinsic resistance in the proposed behavioral models are discussed. All predictions and theoretical assumptions are supported by simulations and experiments. This contribution helps to find a cheaper and more effective way to preliminary laboratory tests without expensive on-chip fabrication of special active elements.

  6. Soft and hard computing approaches for real-time prediction of currents in a tide-dominated coastal area

    Charhate, S.B.; Deo, M.C.; SanilKumar, V.

    , Mumbai, India 2National Institute of Oceanography, Goa, India The manuscript was received on 12 December 2006 and was accepted after revision for publication on 19 September 2007. DOI: 10.1243/14750902JEME77 Abstract: The prediction of tidal currents...) (prediction by GP) JEME77 © IMechE 2007Proc. IMechE Vol. 221 Part M: J. Engineering for the Maritime Environment 153Real-time prediction of currents of the direction sensor was ±2°. Surface currents to the measured data using the least square method. The tidal...

  7. Finite element formulation using magnetic vector potential approach: effects of displacement current in magneto-electro-elastic cylindrical shells

    Displacement current is associated with the generation of magnetic fields due to time-varying electric fields. The harmonic response of a magneto-electro-elastic axisymmetric cylinder accounting for displacement current is carried out using the semi-analytical finite element method. The non-conservative electric field is represented using a magnetic vector potential. Studies are carried out for the first circumferential harmonics of the shell structure with the clamped–free boundary condition. The contribution made to the magnetic flux density by the electric displacement current is very small at lower frequencies but it becomes significant at higher frequencies

  8. Safety profile of solid lipid nanoparticles loaded with rosmarinic acid for oral use: in vitro and animal approaches

    Madureira, Ana Raquel; Nunes, Sara; Campos, Débora A; Fernandes, João C; Marques, Cláudia; Zuzarte, Monica; Gullón, Beatriz; Rodríguez-Alcalá, Luís M; Calhau, Conceição; Sarmento, Bruno; Gomes, Ana Maria; Pintado, Maria Manuela; Reis, Flávio

    2016-01-01

    Rosmarinic acid (RA) possesses several protective bioactivities that have attracted increasing interest by nutraceutical/pharmaceutical industries. Considering the reduced bioavailability after oral use, effective (and safe) delivery systems are crucial to protect RA from gastrointestinal degradation. This study aims to characterize the safety profile of solid lipid nanoparticles produced with Witepsol and Carnauba waxes and loaded with RA, using in vitro and in vivo approaches, focused on genotoxicity and cytotoxicity assays, redox status markers, hematological and biochemical profile, liver and kidney function, gut bacterial microbiota, and fecal fatty acids composition. Free RA and sage extract, empty nanoparticles, or nanoparticles loaded with RA or sage extract (0.15 and 1.5 mg/mL) were evaluated for cell (lymphocytes) viability, necrosis and apoptosis, and antioxidant/prooxidant effects upon DNA. Wistar rats were orally treated for 14 days with vehicle (control) and with Witepsol or Carnauba nanoparticles loaded with RA at 1 and 10 mg/kg body weight/d. Blood, urine, feces, and several tissues were collected for analysis. Free and loaded RA, at 0.15 mg/mL, presented a safe profile, while genotoxic potential was found for the higher dose (1.5 mg/mL), mainly by necrosis. Our data suggest that both types of nanoparticles are safe when loaded with moderate concentrations of RA, without in vitro genotoxicity and cytotoxicity and with an in vivo safety profile in rats orally treated, thus opening new avenues for use in nutraceutical applications. PMID:27536103

  9. Weight-of-evidence approach in assessment of ecotoxicological risks of acid sulphate soils in the Baltic Sea river estuaries.

    Wallin, Jaana; Karjalainen, Anna K; Schultz, Eija; Järvistö, Johanna; Leppänen, Matti; Vuori, Kari-Matti

    2015-03-01

    Acidity and leaching of metals from acid sulphate soils (ASSs) impair the water quality of receiving surface waters. The largest ASS areas in Europe are found in the coasts of the northern Baltic Sea. We used weight-of-evidence (WoE) approach to assess potential risks in 14 estuary sites affected by ASS in the Gulf of Finland, northern Baltic Sea. The assessment was based on exposure and effect profiles utilizing sediment and water metal concentrations and concurrent pH variation, sediment toxicity tests using the luminescent bacterium Vibrio fischeri and the midge Chironomus riparius, and the ecological status of benthic macroinvertebrate communities. Sediment metal concentrations were compared to national sediment quality criteria/guidelines, and water metal concentrations to environmental quality standards (EQSs). Hazard quotients (HQs) were established for maximum aluminium, cadmium and zinc concentrations at low pH based on applicable US EPA toxicity database. Sediment metal concentrations were clearly elevated in most of the studied estuaries. The EQS of cadmium (0.1 μg/l) was exceeded in 3 estuaries out of 14. The pH-minima were below the national threshold value (5.5) between good and satisfactory water quality in 10 estuaries. V. fischeri bioluminescence indicated toxicity of the sediments but toxic response was not observed in the C. riparius emergence test. Benthic invertebrate communities were deteriorated in 6 out of 14 sites based on the benthic invertebrate quality index. The overall ecotoxicological risk was assessed as low in five, moderate in three and high in five of the estuary sites. The risk assessment utilizing the WoE approach indicated that harmful effects of ASSs are likely to occur in the Baltic Sea river estuaries located at the ASS hotspot area. PMID:25506908

  10. Predicting the effects of process parameters on the performance of phosphoric acid fuel cells using a 3-D numerical approach

    In this work, a three-dimensional model of a phosphoric acid fuel cell (PAFC) has been developed and has been applied to investigate the effects of process parameters on the fuel cell performance. Simulation results show good agreement with experimental data found in the literature. The model accounts for the local distribution of the concentration of reactant and product gases in the anode and cathode flow regions and the electrical potential distribution on the surface of the cathode electrode, in several cases of different utilization of the reactant gases and different values of current density. The developed model predicts with satisfactory accuracy the average cell and stack voltage and also the generated power

  11. An Approach to Suppressing Both Shaft Voltage and Leakage Current in an AC Motor Driven by a Voltage-Source PWM Inverter

    Doumoto, Takafumi; Akagi, Hirofumi

    This paper proposes a practical approach to suppressing both shaft voltage and leakage current in an ac motor driven by a voltage-source PWM inverter. This approach is characterized by using a neutral line of the ac motor. A common-mode inductor is connected between the inverter and the motor. Moreover, a resistor and a capacitor are connected in series between the motor neutral point and the inverter negative dc bus. This unique circuit configuration makes the common-mode inductor effective in reducing the common-mode voltage appearing at the motor terminals. As a result, both shaft voltage and ground current are significantly suppressed with low cost. Over-voltages at the end of a cable can be suppressed by a normal-mode inductor and a resistor which are connected in parallel. The validity and effectiveness of the new approach are verified by experimental results from a 5-kVA laboratory system.

  12. Innovative Disulfide Esters of Dithiocarbamic Acid as Women-Controlled Contraceptive Microbicides: A Bioisosterism Approach.

    Mandalapu, Dhanaraju; Lal, Nand; Kumar, Lokesh; Kushwaha, Bhavana; Gupta, Sonal; Kumar, Lalit; Bala, Veenu; Yadav, Santosh K; Singh, Pratiksha; Singh, Nidhi; Maikhuri, Jagdamba P; Sankhwar, Satya N; Shukla, Praveen K; Siddiqi, Imran; Gupta, Gopal; Sharma, Vishnu L

    2015-10-01

    In an ongoing effort to discover an effective, topical, dual-function, non-surfactant contraceptive vaginal microbicide, a novel series of 2,2'-disulfanediylbis(3-(substituted-1-yl)propane-2,1-diyl) disubstituted-1-carbodithioates were designed by using a bioisosterism approach. Thirty-three compounds were synthesized, and interestingly, most demonstrated multiple activities: they were found to be spermicidal at a minimal effective concentration of 1-0.001 %, trichomonacidal against drug-susceptible and resistant Trichomonas strains at minimal inhibitory concentration (MIC) ranges of 10.81-377.64 and 10.81-754.14 μM, respectively, and fungicidal at MIC 7.93-86.50 μM. These compounds were also found to be non-cytotoxic to human cervical (HeLa) epithelial cells and vaginal microflora (Lactobacilli) in vitro. The most promising compound, 2,2'-disulfanediylbis(3-(pyrrolidin-1-yl)propane-2,1-diyl)dipyrrolidine-1-carbodithioate (5), exhibited spermicidal activity 15-fold higher than that of the marketed spermicide Nonoxynol-9 (N-9) and also demonstrated microbicidal potency. To identify common structural features required for spermicidal activity, a 3D-QSAR analysis was carried out, as well as in vivo efficacy studies and fluorescent labeling studies to determine the biological targets of compound 5. PMID:26337025

  13. Nucleic acid-based approaches to investigate microbial-related cheese quality defects

    Daniel eO Sullivan

    2013-01-01

    Full Text Available AbstractThe microbial profile of cheese is a primary determinant of cheese quality. Microorganisms can contribute to aroma and taste defects, form biogenic amines, cause gas and secondary fermentation defects, and can contribute to cheese pinking and mineral deposition issues. These defects may be as a result of seasonality and the variability in the composition of the milk supplied, variations in cheese processing parameters, as well as the nature and number of the non-starter microorganisms which come from the milk or other environmental sources. Such defects can be responsible for production and product recall costs and thus represent a significant economic burden for the dairy industry worldwide. Traditional non-molecular approaches are often considered biased and have inherently slow turnaround times. Molecular techniques can provide early and rapid detection of defects that result from the presence of specific spoilage microbes and, ultimately, assist in enhancing cheese quality and reducing costs. Here we review the DNA-based methods that are available to detect/quantify spoilage bacteria, and relevant metabolic pathways, in cheeses and, in the process, highlight how these strategies can be employed to improve cheese quality and reduce the associated economic burden on cheese processors.

  14. A Practical approach for fault component network for Current and Voltage Phasor Diagram in Power Electronic Environment

    Mr. Ashish Choubey

    2011-09-01

    Full Text Available In many large-scale power plants, the structure of its auxiliary power system is complex, and the coordination of its relay protections is difficult. To enhance power supply reliability for the user terminals in the case of the distribution system to avoid interference by the fault again, rapidly complete the automatic identification, positioning, automatic fault isolation, network reconfiguration until the resumption of supply of non-fault section, a microprocessor-based relay protection device has developed. As the fault component theory is widely used in microcomputer protection, and fault component exists in the network of fault component, it is necessary to build up the fault component network when short circuit fault emerging and to draw the current and voltage component phasor diagram at fault point. We proposed a special phase sequence component based on the boundary condition. We analysis the velocity according to the relationship between analysis formula and phasor diagram and current in fault component boundary conditions and sequence voltage and current in boundary conditions. The negative and zero sequence component current and voltage at fault point are the same as fault component. The positive sequence component current and voltage at fault point are different from the fault component. So we consider the positive sequences according to that sequences we analyze the fault point

  15. Effects of Perfluorooctanoic Acid on Metabolic Profiles in Brain and Liver of Mouse Revealed by a High-throughput Targeted Metabolomics Approach

    Nanyang Yu; Si Wei; Meiying Li; Jingping Yang; Kan Li; Ling Jin; Yuwei Xie; Giesy, John P; Xiaowei Zhang; Hongxia Yu

    2016-01-01

    Perfluorooctanoic acid (PFOA), a perfluoroalkyl acid, can result in hepatotoxicity and neurobehavioral effects in animals. The metabolome, which serves as a connection among transcriptome, proteome and toxic effects, provides pathway-based insights into effects of PFOA. Since understanding of changes in the metabolic profile during hepatotoxicity and neurotoxicity were still incomplete, a high-throughput targeted metabolomics approach (278 metabolites) was used to investigate effects of expos...

  16. Axial buckling analysis of a slender current-carrying nanowire acted upon by a magnetic field using the surface energy approach

    The axial buckling behavior of magnetically affected current-carrying nanowires is studied accounting for the surface energy effect. Using Euler–Bernoulli beam theory, the Lorentz force on the nanowire is determined and the governing equations are established. By application of the Galerkin approach and assumed mode method, the critical axial compressive load of the nanostructure is evaluated in the cases of simply supported and fully clamped ends. The effects of surface energy, electric current, strength of the magnetic field, slenderness ratio, and nanowire’s radius on the axial buckling loads are comprehensively discussed. The obtained results reveal that both the electric current and exerted magnetic field endanger the axial stability of the nanowire. For high levels of electric current or magnetic field strength, the surface effect becomes significant in the axial buckling performance of the nanostructure. (paper)

  17. A metal-free aerobic oxidation of nitrotoluenes catalyzed by N,N',N″-trihydroxyisocyanuric acid (THICA) and a novel approach to the catalyst.

    Wang, Kai; Zhou, Zhiming; Song, Jinhong; Bi, Lixue; Shen, Ning; Wu, Yukai; Chen, Fuxue; Wen, Hongliang

    2010-12-15

    A metal-free catalytic system with N,N',N″-trihydroxyisocyanuric acid (THICA) as the catalyst for the oxidation of nitrotoluenes is introduced, and a novel Pd-free approach for the synthesis of THICA was developed. In a solution of acetic acid, THICA and concentrated nitric acid, nitrotoluenes especially polynitrotoluenes such as 2,4,6-trinitrotoluene (TNT), were converted into the desired carboxylic acids under 0.2 MPa of O(2) at 100°C with yields up to 99%. THICA was synthesized from N-hydroxyphtalimide through a four-step synthesis in a total yield of 46%. A possible mechanism of this catalytic process was proposed where NO(2) and nitric acid first induced a radical of THICA, which then abstracts a hydrogen atom from the methyl on the aromatic ring to form a benzyl radical. This radical then initiates subsequent reactions. The production of the benzyl radical was supported by ESR measurements. PMID:20869170

  18. Effects of Elaidic Acid on Lipid Metabolism in HepG2 Cells, Investigated by an Integrated Approach of Lipidomics, Transcriptomics and Proteomics

    Vendel Nielsen, Lone; Hansen, Toke Peter Krogager; Young, Clifford;

    2013-01-01

    Trans fatty acid consumption in the human diet can cause adverse health effects, such as cardiovascular disease, which is associated with higher total cholesterol, a higher low density lipoprotein-cholesterol level and a decreased high density lipoprotein-cholesterol level. The aim of the study was...... to elucidate the hepatic response to the most abundant trans fatty acid in the human diet, elaidic acid, to help explain clinical findings on the relationship between trans fatty acids and cardiovascular disease. The human HepG2 cell line was used as a model to investigate the hepatic response to...... elaidic acid in a combined proteomic, transcriptomic and lipidomic approach. We found many of the proteins responsible for cholesterol synthesis up-regulated together with several proteins involved in the esterification and hepatic import/export of cholesterol. Furthermore, a profound remodeling of the...

  19. Developing a New Teaching Approach for the Chemical Bonding Concept Aligned with Current Scientific and Pedagogical Knowledge

    Nahum, Tami Levy; Mamlok-Naaman, Rachel; Hofstein, Avi; Krajcik, Joseph

    2007-01-01

    The traditional pedagogical approach for teaching chemical bonding is often overly simplistic and not aligned with the most up-to-date scientific models. As a result, high-school students around the world lack fundamental understanding of chemical bonding. In order to improve students' understanding of this concept, it was essential to propose a…

  20. Hamiltonian Approach to Internal Wave-Current Interactions in a Two-Media Fluid with a Rigid Lid

    Compelli, Alan

    2016-01-01

    We examine a two-media 2-dimensional fluid system consisting of a lower medium bounded underneath by a flatbed and an upper medium with a free surface with wind generated surface waves but considered bounded above by a lid by an assumption that surface waves have negligible amplitude. An internal wave driven by gravity which propagates in the positive $x$-direction acts as a free common interface between the media. The current is such that it is zero at the flatbed but a negative constant, due to an assumption that surface winds blow in the negative $x$-direction, at the lid. We are concerned with the layers adjacent to the internal wave in which there exists a depth dependent current for which there is a greater underlying than overlying current. Both media are considered incompressible and having non-zero constant vorticities. The governing equations are written in canonical Hamiltonian form in terms of the variables, associated to the wave (in a presence of a constant current). The resultant equations of m...

  1. Improving Students' Ability to Intuitively Infer Resistance from Magnitude of Current and Potential Difference Information: A Functional Learning Approach

    Chasseigne, Gerard; Giraudeau, Caroline; Lafon, Peggy; Mullet, Etienne

    2011-01-01

    The study examined the knowledge of the functional relations between potential difference, magnitude of current, and resistance among seventh graders, ninth graders, 11th graders (in technical schools), and college students. It also tested the efficiency of a learning device named "functional learning" derived from cognitive psychology on the…

  2. High-frequency, long-duration water sampling in acid mine drainage studies: a short review of current methods and recent advances in automated water samplers

    Chapin, Thomas

    2015-01-01

    Hand-collected grab samples are the most common water sampling method but using grab sampling to monitor temporally variable aquatic processes such as diel metal cycling or episodic events is rarely feasible or cost-effective. Currently available automated samplers are a proven, widely used technology and typically collect up to 24 samples during a deployment. However, these automated samplers are not well suited for long-term sampling in remote areas or in freezing conditions. There is a critical need for low-cost, long-duration, high-frequency water sampling technology to improve our understanding of the geochemical response to temporally variable processes. This review article will examine recent developments in automated water sampler technology and utilize selected field data from acid mine drainage studies to illustrate the utility of high-frequency, long-duration water sampling.

  3. Preparative isolation of pseudolaric acids A and B, and their glucosides from the root bark of Pseudolarix kaempferi using high-speed counter-current chromatography.

    Han, Quan-Bin; Wong, Lina; Lai, Fanny; Yang, Nian-Yun; Song, Jing-Zheng; Qiao, Chun-Feng; Xu, Hong-Xi

    2009-01-01

    In order to provide the chemical markers for the quality control of herbal medicines, four diterpenoids, pseudolaric acids A and B (PAA and PAB), and their glucosides were isolated from the methanol extract of the Chinese herb Pseudolarix kaempferi using high-speed counter-current chromatography (HSCCC). The diphase solvent system was n-hexane/EtOAc/MeOH/H(2)O which was used at two ratios (5:5:5:5 and 1:9:4:6 by volume) in the separation of pseudolaric acids and their glycosides, respectively. As a result, PAA (14 mg), PAB (129 mg), PAA-O-beta-D-glucopyranoside (8 mg, PAAG), and PAB-O-beta-D-glucopyranoside (42 mg, PABG) were obtained from 0.5 g of the crude extract. Their purities were determined to be above 97% by HPLC analysis. Their chemical structures were confirmed by( 1)H and( 13)C NMR analysis or HPLC comparison with the reference compounds. PMID:19072902

  4. Intellectual property law and competition law in China - Analysis of the current framework and comparison with the EU approach

    Yeung Nga Man

    2014-05-01

    Full Text Available In this paper Yeung Nga Man looks at the question of protection of intellectual property rights in the Chinese legal system with comparative reference to policy and practice in the European Union. What is the best way to stimulate competition but yet also protect innovation? Part I of the essay examines the present IPRs protection in China. In Part II, contrary to the myth that competition and IP law conflict with one another, the author argues that both foster innovation and development, and enhance consumer welfare. Part III discusses the competition law regime in China with a specific focus on AML and evaluation of the enforcement of the regime. Part IV outlines the European Union approach, which China might consider adopting. Part V discusses the Block Exemptions approach from the E.U. on horizontal agreements.

  5. In-Silico Drug Design: A revolutionary approach to change the concept of current Drug Discovery Process

    Lakhyajit Boruah, Aparoop Das, Lalit Mohan Nainwal, Neha Agarwal*, Brajesh Shankar

    2013-06-01

    Full Text Available Computational methods play a central role in modern drug discovery process. It includes the design andmanagement of small molecule libraries, initial hit identification through virtual screening, optimization ofthe affinity as well as selectivity of hits and improving the physicochemical properties of the leadcompounds. In this review article, computational drug designing approaches have been elucidated anddiscussed. The key considerations and guidelines for virtual chemical library design and whole drugdiscovery process. Traditional approach for discovery of a new drug is a costly and time consuming affairbesides not being so productive. A number of potential reasons witness choosing the In-silico method ofdrug design to be a more wise and productive approach. There is a general perception that applied sciencehas not kept pace with the advances of basic science. Therefore, there is a need for the use of alternativetools to get answers on efficacy and safety faster, with more certainty and at lower cost. In-silico drugdesign can play a significant role in all stages of drug development from the initial lead designing to finalstage clinical development.

  6. Approach to high stability beta limit and its control by fast wave current drive in reversed field pinch plasma

    Before the generation of steady state, dynamo-free RFP configuration by rf current driving scheme, it is necessary to find an optimum configuration into high stability beta limit against m=1 resonant resistive MHD modes and reducing nonlinearly turbulent level with less rf power. As first step to the optimization study, we are interested in partially relaxed state model (PRSM) RFP configuration, which is considered to be closer to a relaxed state at finite beta since it has force-free fields for poloidal direction with a relatively shorter characteristic length of relaxation and a relatively higher stability beta limit to m=1 resonant ideal MHD modes. The stability beta limit to m=1 resonant resistive MHD modes can be predicted to be relatively high among other RFP models and to be enhanced by the current density profile control using fast magnetosonic waves (FMW), which are accessible to high density region with strong absorption rate. (author)

  7. Impact of radioactivity on the environment: problems, state of current knowledge and approaches for identification of radioprotection criteria

    There is currently a revitalized concern about the potential impact of ionizing radiation on the environment that calls for the construction of a system ensuring an adequate radioprotection of the non-human biota and their associated biotopes. This paper first sets the context of the problem both, with respect to the general philosophy of environmental protection as a whole, but also with respect to the consideration of the environment achieved so far in the purpose of human radioprotection. The current accumulated knowledge on the effects of ionizing radiation to biota (fauna and flora) is then briefly reviewed, encompassing effects at individual and community/ecosystem level, situations of acute and chronic exposure to high and low doses, finally leading to the identification of the most critical gaps in scientific knowledge: effects of mixed low dose rates in chronic exposure to communities and ecosystems. The most significant current international efforts towards the identification of environmental radioprotection criteria and standards are finally presented along with some relevant national examples. (author)

  8. Integrated Approach to the H-mode Pedestal Dynamics: Effects of Bootstrap Current and Resonant Magnetic Perturbations on ELMs

    Full text: The accurate prediction of Edge Localized Modes (ELMs) and their mitigation are critical for sustainable discharge operation. Two main research questions are elucidated in this study: 1. What are the effects of uncertainties in the bootstrap current computations on the ELM stability predictions? 2. How do the resonant magnetic perturbations (RMPs) that are introduced to mitigate ELMs change the overall plasma confinement? In order to answer these questions, high physics fidelity codes that have been developed during the SciDAC CPES, CSWIM, and FACETS projects are used. The computation starts from an 'equilibrium cloud' generated using the FACETS framework. The edge plasma profiles are advanced using kinetic neoclassical XGC0 code. The resulting plasma pressure and boot-strap current profiles are updated in the initial equilibria by the M3D-OMP code. The updated equilibrium is analyzed in the FLUXGRID component of FACETS that incorporates several bootstrap current models. The bootstrap current predictions from these models are compared with the predictions from XGC0. Conclusions about validity ranges for each model are deduced. Differences in the predictions for the ELM stability thresholds that result from uncertainties in the computations of bootstrap current are determined using ideal MHD stability codes. The core plasma profiles from updated equilibria are advanced to steady state solutions using the integrated whole-device modeling FACETS code. The edge plasma profiles are maintained using the UEDGE component of FACETS. The effect of 3D magnetic perturbations on plasma confinement is investigated in these coupled core-edge simulations. The magnetic perturbation effect has been recently implemented in UEDGE using the magnetic field line diffusivity model. The applied RMPs degrade the edge confinement by modifying plasma profiles to the MHD stable profiles. The RMP effect on overall plasma confinement is determined by comparing the energy confinement

  9. Form factor for a two-particle system within a relativistic quasipotential approach: Case of arbitrary masses and of a vector current

    A new relativistic form factor for a bound two-particle system was obtained for the case of a vector current. The present consideration was performed within the relativistic quasipotential approach based on the covariant Hamiltonian formulation of quantum field theory by going over to the three-dimensional relativistic configuration representation for the case of interaction between two relativistic spinless particles of arbitrary mass

  10. Detection of Chlamydia trachomatis by Nucleic Acid Amplification Testing: Our Evaluation Suggests that CDC-Recommended Approaches for Confirmatory Testing Are Ill-Advised

    Schachter, Julius; Chow, Joan M.; Howard, Holly; Bolan, Gail; Moncada, Jeanne

    2006-01-01

    We evaluated three CDC-suggested approaches for confirming positive nucleic acid amplification tests (NAATs) for Chlamydia trachomatis: (i) repeat the original test on the original specimen, (ii) retest the original specimen with a different test, and (iii) perform a different test on a duplicate specimen. For approach 1, specimens (genital swabs or first-catch urine [FCU]) initially positive by the Abbott LCx Probe System Chlamydia trachomatis Assay (LCx; Abbott Laboratories), the APTIMA Com...

  11. [Parasitological characteristics, epidemiological and clinical features, and current control approaches for three major kinds of human schistosomiasis].

    Xu, Xiao-Lin; Zhu, Rong; Zhang, Li-Juan; Guo, Jia-Gang

    2013-06-01

    Schistosomiasis is a tropical disease, which could do serious damage to the people's health, and it hinders the development of the social economy but may be neglected. After a positive control, some countries and regions have blocked the spread of schistosomiasis. However, in the past few years, with the development of social economy, due to the global movement of people, schistosomiasis not only poses a threat to control areas, but also may cause new endemic areas. This article reviews the parasitological characteristics, clinical manifestations, epidemiological situation, and control approaches of three major kinds of human schistosomiasis, schistosomiasis japonica, schistosomiasis haematobia, and schistosomiasis mansoni. PMID:24024456

  12. The risk-benefit task of research ethics committees: An evaluation of current approaches and the need to incorporate decision studies methods

    Bernabe Rosemarie D L C

    2012-04-01

    Full Text Available Abstract Background Research ethics committees (RECs are tasked to assess the risks and the benefits of a trial. Currently, two procedure-level approaches are predominant, the Net Risk Test and the Component Analysis. Discussion By looking at decision studies, we see that both procedure-level approaches conflate the various risk-benefit tasks, i.e., risk-benefit assessment, risk-benefit evaluation, risk treatment, and decision making. This conflation makes the RECs’ risk-benefit task confusing, if not impossible. We further realize that RECs are not meant to do all the risk-benefit tasks; instead, RECs are meant to evaluate risks and benefits, appraise risk treatment suggestions, and make the final decision. Conclusion As such, research ethics would benefit from looking beyond the procedure-level approaches and allowing disciplines like decision studies to be involved in the discourse on RECs’ risk-benefit task.

  13. Low platinum, high limiting current density of the PEMFC (proton exchange membrane fuel cell) based on multilayer cathode catalyst approach

    Novel multilayer cathode electrodes structures for PEMFC (proton exchange membrane fuel cell) based on sputtering technique were developed to provide high performance with low loading Pt of 0.05 mg/cm² compared to the standard MEA (membrane electrode assembly) cathode (∼0.2–0.3 mg/cm²). Different configurations of cathode catalyst layer were made by altering Pt and CN (Carbon–Nafion) ink carefully prepared on gas diffusion layer containing MPL (micro porous layer). The performances of PEMFC containing the multilayer electrodes were compared based on their measured polarization curves. Higher limiting current densities were achieved compared to standard MEA with platinum loading of 0.2 mg/cm² both at the cathode and the anode sides. Limiting current densities over 1.1 A/cm2, 1.2 A/cm2 and 1.4 A/cm2 were reached whereas maximum powers were in the range of 500 mW/cm² at 600 mW/cm². The good performances obtained can be due to the structural improvement which has contributed to a better catalyst utilization compared to conventional methods. A CN loading inferior to 0.24 mg/cm² between each layer is preferred for multilayer electrode. - Highlights: • Multilayer cathode of PEM fuel cell. • Enhanced performances with carbon–Nafion layer of PEM fuel cell. • Effect of the number of Pt sputtered layers on cell performance. • Increased power densities achieved. • Increased limiting current densities achieved

  14. On the energy-momentum current of the electromagnetic field in a pre-metric axiomatic approach, 1

    Hehl, F W; Hehl, Friedrich W.; Obukhov, Yuri N.

    2001-01-01

    We complete a metric-free axiomatic framework for electrodynamics by introducing the appropriate energy-momentum current Sigma of the electromagnetic field. We start from the Lorentz force density and motivate the form of Sigma. Then we postulate it (fourth axiom) and discuss its properties. In particular, it is found that Sigma is traceless and invariant under an electric-magnetic reciprocity transformation. By using the Maxwell-Lorentz spacetime relation (fifth axiom), Sigma is also shown to be symmetric, that is, it has 9 independent components

  15. Computer-Aided Diagnosis in Mammography Using Content-Based Image Retrieval Approaches: Current Status and Future Perspectives

    Bin Zheng

    2009-06-01

    Full Text Available As the rapid advance of digital imaging technologies, the content-based image retrieval (CBIR has became one of the most vivid research areas in computer vision. In the last several years, developing computer-aided detection and/or diagnosis (CAD schemes that use CBIR to search for the clinically relevant and visually similar medical images (or regions depicting suspicious lesions has also been attracting research interest. CBIR-based CAD schemes have potential to provide radiologists with “visual aid” and increase their confidence in accepting CAD-cued results in the decision making. The CAD performance and reliability depends on a number of factors including the optimization of lesion segmentation, feature selection, reference database size, computational efficiency, and relationship between the clinical relevance and visual similarity of the CAD results. By presenting and comparing a number of approaches commonly used in previous studies, this article identifies and discusses the optimal approaches in developing CBIR-based CAD schemes and assessing their performance. Although preliminary studies have suggested that using CBIR-based CAD schemes might improve radiologists’ performance and/or increase their confidence in the decision making, this technology is still in the early development stage. Much research work is needed before the CBIR-based CAD schemes can be accepted in the clinical practice.

  16. Quantitative assessment of sensory functions after 3 surgical approaches for trigeminal neuralgia by current perception threshold measurement

    Chen Ruoping; Ouyang Huoniu; Wang Bingyu; Ding Meixiu; Charles J. Hodge Jr.

    2008-01-01

    Objective: To quantitatively identify and grade trigeminal sensory functions after 3 major surgical procedures of trigeminal neuralgia using a newly developed quantitative sensory testing technique, current perception threshold measurement (CPTM). Methods: In the current study, there were 48 trigeminal neuralgia patients without history of prior surgical treatment. These patients received one of the following 3 surgical procedures, microvascular decompression (MVD), peripheral nerve block with alcohol (PNB), or percutaneous radiofrequency thermocoagulation (PRFT). The quantitative sensory testing measurement, CPTM, and conventional qualitative sensory testing measurements were performed preoperatively and postoperatively to evaluate and grade the trigeminal sensory functions.All 3 major cutaneous sensory fiber types, large myelinated fibers (A beta), small myelinated fibers (A delta) and unmyelinated fibers(C) were allowed to quantitatively evaluate and grade by CPTM. The results of the measurements were statistically analyzed using a one-way analysis of variance (single factor). Each subject was his/her own control for comparison of the preoperative to postoperative state on the asymptomatic and symptomatic sides. Subjects were tested 48 h preoperatively and 4 weeks postoperatively. Results: PNB with alcohol and PRFT caused significant sensory dysfunction postoperatively in every fiber type, indicating damage to all fibers. On the contrary, the sensory function in all 3 fiber types was unchanged after MVD management. Conclusion: Among the 3 major surgical procedures tested,only MVD preserves sensory function in trigeminal system. CPTM is of quantitative nature on the evaluation of sensory functions of nerve fibers

  17. Synthetic Approaches to L-Iduronic Acid and L-Idose: Key Building Blocks for the Preparation of Glycosaminoglycan Oligosaccharides.

    Mohamed, Shifaza; Ferro, Vito

    2015-01-01

    L-Iduronic acid (IdoA) is an important monosaccharide component of glycosaminoglycans (GAGs) such as heparin, heparan sulfate and dermatan sulfate. GAGs are complex, highly sulfated polysaccharides that mediate a multitude of physiological and pathological processes via their interactions with a range of diverse proteins. The main challenge in the synthesis of GAG oligosaccharides is the efficient gram-scale preparation of IdoA building blocks since neither IdoA nor L-idose is commercially available or readily accessible from natural sources. In this review, the different synthetic approaches for the preparation of IdoA and its derivatives, including L-idose, are presented and discussed. Derivatives of the latter are often used in GAG synthesis and are elaborated to IdoA via selective oxidation at C-6 after incorporation into a GAG chain. Particular focus will be given to the preparation of IdoA synthons most commonly used for GAG oligosaccharide synthesis, and on the progress made since the last systematic review in this area. PMID:26613814

  18. Deciphering Ascorbic Acid Regulatory Pathways in Ripening Tomato Fruit Using a Weighted Gene Correlation Network Analysis Approach

    Chao Gao; Zheng Ju; Shan Li; Jinhua Zuo; Daqi Fu; Huiqin Tian; Yunbo Luo; Benzhong Zhu

    2013-01-01

    Genotype is generally determined by the co-expression of diverse genes and multiple regulatory pathways in plants. Gene co-expression analysis combining with physiological trait data provides very important information about the gene function and regulatory mechanism. L-Ascorbic acid (AsA), which is an essential nutrient component for human health and plant metabolism, plays key roles in diverse biological processes such as cell cycle, cell expansion, stress resistance, hormone synthesis, and signaling. Here, we applied a weighted gene correlation network analysis approach based on gene expression values and AsA content data in ripening tomato (Solanum lycopersicum L.) fruit with different AsA content levels, which leads to identification of AsA relevant modules and vital genes in AsA regulatory pathways. Twenty-four modules were compartmentalized according to gene expression profiling. Among these modules, one negatively related module containing genes involved in redox processes and one positively related module enriched with genes involved in AsA biosynthetic and recycling pathways were further analyzed. The present work herein indicates that redox pathways as well as hormone-signal pathways are closely correlated with AsA accumulation in ripening tomato fruit, and allowed us to prioritize candidate genes for follow-up studies to dissect this interplay at the biochemical and molecular level.

  19. Two-stage sample-to-answer system based on nucleic acid amplification approach for detection of malaria parasites.

    Liu, Qing; Nam, Jeonghun; Kim, Sangho; Lim, Chwee Teck; Park, Mi Kyoung; Shin, Yong

    2016-08-15

    Rapid, early, and accurate diagnosis of malaria is essential for effective disease management and surveillance, and can reduce morbidity and mortality associated with the disease. Although significant advances have been achieved for the diagnosis of malaria, these technologies are still far from ideal, being time consuming, complex and poorly sensitive as well as requiring separate assays for sample processing and detection. Therefore, the development of a fast and sensitive method that can integrate sample processing with detection of malarial infection is desirable. Here, we report a two-stage sample-to-answer system based on nucleic acid amplification approach for detection of malaria parasites. It combines the Dimethyl adipimidate (DMA)/Thin film Sample processing (DTS) technique as a first stage and the Mach-Zehnder Interferometer-Isothermal solid-phase DNA Amplification (MZI-IDA) sensing technique as a second stage. The system can extract DNA from malarial parasites using DTS technique in a closed system, not only reducing sample loss and contamination, but also facilitating the multiplexed malarial DNA detection using the fast and accurate MZI-IDA technique. Here, we demonstrated that this system can deliver results within 60min (including sample processing, amplification and detection) with high sensitivity (malaria in low-resource settings. PMID:27031184

  20. Automatic identification approach for high-performance liquid chromatography-multiple reaction monitoring fatty acid global profiling.

    Tie, Cai; Hu, Ting; Jia, Zhi-Xin; Zhang, Jin-Lan

    2015-08-18

    Fatty acids (FAs) are a group of lipid molecules that are essential to organisms. As potential biomarkers for different diseases, FAs have attracted increasing attention from both biological researchers and the pharmaceutical industry. A sensitive and accurate method for globally profiling and identifying FAs is required for biomarker discovery. The high selectivity and sensitivity of high-performance liquid chromatography-multiple reaction monitoring (HPLC-MRM) gives it great potential to fulfill the need to identify FAs from complicated matrices. This paper developed a new approach for global FA profiling and identification for HPLC-MRM FA data mining. Mathematical models for identifying FAs were simulated using the isotope-induced retention time (RT) shift (IRS) and peak area ratios between parallel isotope peaks for a series of FA standards. The FA structures were predicated using another model based on the RT and molecular weight. Fully automated FA identification software was coded using the Qt platform based on these mathematical models. Different samples were used to verify the software. A high identification efficiency (greater than 75%) was observed when 96 FA species were identified in plasma. This FAs identification strategy promises to accelerate FA research and applications. PMID:26189701