WorldWideScience

Sample records for current knowledge limitations

  1. Current limiters

    Energy Technology Data Exchange (ETDEWEB)

    Loescher, D.H. [Sandia National Labs., Albuquerque, NM (United States). Systems Surety Assessment Dept.; Noren, K. [Univ. of Idaho, Moscow, ID (United States). Dept. of Electrical Engineering

    1996-09-01

    The current that flows between the electrical test equipment and the nuclear explosive must be limited to safe levels during electrical tests conducted on nuclear explosives at the DOE Pantex facility. The safest way to limit the current is to use batteries that can provide only acceptably low current into a short circuit; unfortunately this is not always possible. When it is not possible, current limiters, along with other design features, are used to limit the current. Three types of current limiters, the fuse blower, the resistor limiter, and the MOSFET-pass-transistor limiters, are used extensively in Pantex test equipment. Detailed failure mode and effects analyses were conducted on these limiters. Two other types of limiters were also analyzed. It was found that there is no best type of limiter that should be used in all applications. The fuse blower has advantages when many circuits must be monitored, a low insertion voltage drop is important, and size and weight must be kept low. However, this limiter has many failure modes that can lead to the loss of over current protection. The resistor limiter is simple and inexpensive, but is normally usable only on circuits for which the nominal current is less than a few tens of milliamperes. The MOSFET limiter can be used on high current circuits, but it has a number of single point failure modes that can lead to a loss of protective action. Because bad component placement or poor wire routing can defeat any limiter, placement and routing must be designed carefully and documented thoroughly.

  2. Global Epidemiology of HIV Among Women and Girls Who Use or Inject Drugs: Current Knowledge and Limitations of Existing Data.

    Science.gov (United States)

    Larney, Sarah; Mathers, Bradley M; Poteat, Tonia; Kamarulzaman, Adeeba; Degenhardt, Louisa

    2015-06-01

    Women and girls who use and inject drugs are a critical population at risk of HIV. In this article, we review data on the epidemiology of drug use and injection among women globally and HIV prevalence among women and girls who use and inject drugs. Women and girls comprise one-third of people who use and inject drugs globally. There is substantial variation in HIV prevalence in this population, between and within countries. There is a pronounced lack of data examining HIV risk among particularly vulnerable subpopulations of women who use and inject drugs, including women who have sex with women, transgender women, racial and ethnic minority women, and young women. Women who use and inject drugs experience stigma and discrimination that affect access to services, and high levels of sexual risk exposures. There are significant gaps in our understanding of the epidemiology of drug use and injecting among women and girls and HIV risk and prevalence in this population. Women are frequently underrepresented in studies of drug use and HIV risk and prevalence among people who inject drugs, limiting our understanding of possible sex differences in this population. Most research originates from developed countries and may not be generalizable to other settings. A great deal of work is needed to improve understanding of HIV among particularly vulnerable subpopulations, such as transgender women who use drugs. Better data are critical to efforts to advocate for the needs of women and girls who use and inject drugs.

  3. Adjustable direct current and pulsed circuit fault current limiter

    Science.gov (United States)

    Boenig, Heinrich J.; Schillig, Josef B.

    2003-09-23

    A fault current limiting system for direct current circuits and for pulsed power circuit. In the circuits, a current source biases a diode that is in series with the circuits' transmission line. If fault current in a circuit exceeds current from the current source biasing the diode open, the diode will cease conducting and route the fault current through the current source and an inductor. This limits the rate of rise and the peak value of the fault current.

  4. Limits to tidal current power

    Energy Technology Data Exchange (ETDEWEB)

    Garrett, Chris [Department of Physics and Astronomy, University of Victoria, Victoria, BC (Canada); Cummins, Patrick [Institute of Ocean Sciences, Fisheries and Oceans (Canada)

    2008-11-15

    Estimating the extractable power of tidal currents in channels is a practical question that has received attention recently. Analysis has clearly shown that the power potential is not given by the flux of kinetic energy, as has been commonly assumed. A general formula for the maximum available power is reviewed, along with assessments of the reduction if only partial fences are used, as would be required for navigational and ecological reasons. In typical situations, the maximum power obtainable may be achieved with a surprisingly small number of turbines, especially if allowance is made for the flow reduction caused by drag on the supporting structures of turbines which reduces the maximum power available. Finally, the flow through tidal turbines is compared with the cooling water demands of nuclear reactors generating the same power. (author)

  5. High temperature superconducting fault current limiter

    Science.gov (United States)

    Hull, John R.

    1997-01-01

    A fault current limiter (10) for an electrical circuit (14). The fault current limiter (10) includes a high temperature superconductor (12) in the electrical circuit (14). The high temperature superconductor (12) is cooled below its critical temperature to maintain the superconducting electrical properties during operation as the fault current limiter (10).

  6. Current knowledge of hypertriglyceridemic pancreatitis.

    Science.gov (United States)

    Valdivielso, Pedro; Ramírez-Bueno, Alba; Ewald, Nils

    2014-10-01

    Severe hypertriglyceridemia (HTG) is a well established and the most common cause of acute pancreatitis (AP) after alcohol and gall stone disease. It is alleged to account for up to 10% of all pancreatitis episodes. Studies suggest that in patients with triglyceride (TG) levels>1000 mg/dL (>11.3 mmol/L), hypertriglyceridemia-induced acute pancreatitis (HTGP-AP) occurs in approximately 15-20% of all subjects referred to Lipid Clinics. Until now, there is no clear evidence which patients with severe HTG will develop pancreatitis and which will not. Underlying pathophysiological concepts include hydrolysis of TG by pancreatic lipase and excessive formation of free fatty acids with inflammatory changes and capillary injury. Additionally hyperviscosity and ischemia may play a decisive role. The clinical features of HTG-AP patients are supposed to be no different from patients with AP of other etiologies. Yet, there are well-conducted studies suggesting that HTG-AP is associated with a higher severity and complication rate. Therapeutic measurements in HTG-AP include dietary modifications, different antihyperlipidemic agents, insulin and/or heparin treatment. The beneficial use of plasmapheresis is repeatedly reported and suggested in many studies. Yet, due to the lack of randomized and controlled trials, it is currently unknown if plasmapheresis may improve morbidity and mortality in the clinical setting of HTG-AP. Since there are no commonly accepted clinical guidelines in the management of HTG-AP, there is a definite need for an international, multicenter approach to this important subject. Copyright © 2014 European Federation of Internal Medicine. Published by Elsevier B.V. All rights reserved.

  7. Chronic obstructive pulmonary disease with mild airflow limitation: current knowledge and proposal for future research – a consensus document from six scientific societies

    Directory of Open Access Journals (Sweden)

    Rossi A

    2017-08-01

    Full Text Available Andrea Rossi,1 Bojana Butorac-Petanjek,2 Marco Chilosi,3 Borja G Cosío,4 Matjaz Flezar,5 Nikolaos Koulouris,6 José Marin,7 Neven Miculinic,2 Guido Polese,8 Miroslav Samaržija,9 Sabina Skrgat,5 Theodoros Vassilakopoulos,10 Andrea Vukić-Dugac,9 Spyridon Zakynthinos,10 Marc Miravitlles11 1Pulmonary Unit, University of Verona, Verona, Italy; 2Respiratory Department, University Hospital Centre, Zagreb, Croatia; 3Pathology Unit, University of Verona, Verona, Italy; 4Department of Respiratory Medicine, Hospital Son Espases-IdISPa and CIBERES, Palma, Spain; 5University Clinic of Respiratory and Allergic Diseases, Golnik, Slovenia; 6First Department of Respiratory Medicine, Medical School of National and Kapodistrian University of Athens, Greece; 7Respiratory Medicine, Hospital Universitario Miguel Servet, CIBERES & IISAragon, Zaragoza, Spain; 8Pulmonary Unit, ULSS 22 Bussolengo, Italy; 9Jordanovac Department for Respiratory Diseases, University of Zagreb School of Medicine, University Hospital Centre, Zagreb, Croatia; 10First Department of Critical Care and Pulmonary Services, Evangelismos Hospital, University of Athens, Greece; 11Pneumology Department, Hospital Universitary Vall d’Hebron, Barcelona, Spain Abstract: Chronic obstructive pulmonary disease (COPD is a leading cause of mortality and morbidity worldwide, with high and growing prevalence. Its underdiagnosis and hence undertreatment is a general feature across all countries. This is particularly true for the mild or early stages of the disease, when symptoms do not yet interfere with daily living activities and both patients and doctors are likely to underestimate the presence of the disease. A diagnosis of COPD requires spirometry in subjects with a history of exposure to known risk factors and symptoms. Postbronchodilator forced expiratory volume in 1 second (FEV1/forced vital capacity <0.7 or less than the lower limit of normal confirms the presence of airflow limitation, the severity

  8. Chronic obstructive pulmonary disease with mild airflow limitation: current knowledge and proposal for future research - a consensus document from six scientific societies.

    Science.gov (United States)

    Rossi, Andrea; Butorac-Petanjek, Bojana; Chilosi, Marco; Cosío, Borja G; Flezar, Matjaz; Koulouris, Nikolaos; Marin, José; Miculinic, Neven; Polese, Guido; Samaržija, Miroslav; Skrgat, Sabina; Vassilakopoulos, Theodoros; Vukić-Dugac, Andrea; Zakynthinos, Spyridon; Miravitlles, Marc

    2017-01-01

    Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality and morbidity worldwide, with high and growing prevalence. Its underdiagnosis and hence under-treatment is a general feature across all countries. This is particularly true for the mild or early stages of the disease, when symptoms do not yet interfere with daily living activities and both patients and doctors are likely to underestimate the presence of the disease. A diagnosis of COPD requires spirometry in subjects with a history of exposure to known risk factors and symptoms. Postbronchodilator forced expiratory volume in 1 second (FEV1)/forced vital capacity societies from five European countries have met and developed this document to stimulate the attention of the scientific community on COPD with "mild" airflow limitation. The aim of this document is to highlight some key features of this important concept and help the practicing physician to understand better what is behind "mild" COPD. Future research should address two major issues: first, whether mild airflow limitation represents an early stage of COPD and what the mechanisms underlying the evolution to more severe stages of the disease are; and second, not far removed from the first, whether regular treatment should be considered for COPD patients with mild airflow limitation, either to prevent progression of the disease or to encourage and improve physical activity or both.

  9. Chronic obstructive pulmonary disease with mild airflow limitation: current knowledge and proposal for future research – a consensus document from six scientific societies

    Science.gov (United States)

    Rossi, Andrea; Butorac-Petanjek, Bojana; Chilosi, Marco; Cosío, Borja G; Flezar, Matjaz; Koulouris, Nikolaos; Marin, José; Miculinic, Neven; Polese, Guido; Samaržija, Miroslav; Skrgat, Sabina; Vassilakopoulos, Theodoros; Vukić-Dugac, Andrea; Zakynthinos, Spyridon; Miravitlles, Marc

    2017-01-01

    Chronic obstructive pulmonary disease (COPD) is a leading cause of mortality and morbidity worldwide, with high and growing prevalence. Its underdiagnosis and hence under-treatment is a general feature across all countries. This is particularly true for the mild or early stages of the disease, when symptoms do not yet interfere with daily living activities and both patients and doctors are likely to underestimate the presence of the disease. A diagnosis of COPD requires spirometry in subjects with a history of exposure to known risk factors and symptoms. Postbronchodilator forced expiratory volume in 1 second (FEV1)/forced vital capacity disease. Therefore, we thought that it was worthwhile to analyze further and discuss this stage of “mild COPD”. To this end, representatives of scientific societies from five European countries have met and developed this document to stimulate the attention of the scientific community on COPD with “mild” airflow limitation. The aim of this document is to highlight some key features of this important concept and help the practicing physician to understand better what is behind “mild” COPD. Future research should address two major issues: first, whether mild airflow limitation represents an early stage of COPD and what the mechanisms underlying the evolution to more severe stages of the disease are; and second, not far removed from the first, whether regular treatment should be considered for COPD patients with mild airflow limitation, either to prevent progression of the disease or to encourage and improve physical activity or both. PMID:28919728

  10. Loyalty Programmes : Current Knowledge and Research Directions

    NARCIS (Netherlands)

    Dorotic, Matilda; Bijmolt, Tammo H. A.; Verhoef, Peter C.

    Loyalty programmes (LPs) have increased in number and popularity, but their effects on customer behaviour remain equivocal, due to a lack of understanding of the drivers of LP effectiveness and insufficient generalizable conclusions across prior studies. This paper synthesizes current knowledge

  11. Current-limited electron beam injection

    Science.gov (United States)

    Stenzel, R. L.

    1977-01-01

    The injection of an electron beam into a weakly collisional, magnetized background plasma was investigated experimentally. The injected beam was energetic and cold, the background plasma was initially isothermal. Beam and plasma dimensions were so large that the system was considered unbounded. The temporal and spatial evolution of the beam-plasma system was dominated by collective effects. High-frequency electrostatic instabilities rapidly thermalized the beam and heated the background electrons. The injected beam current was balanced by a return current consisting of background electrons drifting toward the beam source. The drift between electrons and ions gave rise to an ion acoustic instability which developed into strong three-dimensional turbulence. It was shown that the injected beam current was limited by the return current which is approximately given by the electron saturation current. Non-Maxwellian electron distribution functions were observed.

  12. Investigating fuel-cell transport limitations using hydrogen limiting current

    OpenAIRE

    Spingler, FB; Phillips, A; Schuler, T; Tucker, MC; Weber, AZ

    2017-01-01

    © 2017 Hydrogen Energy Publications LLC Reducing mass-transport losses in polymer-electrolyte fuel cells (PEFCs) is essential to increase their power density and reduce overall stack cost. At the same time, cost also motivates the reduction in expensive precious-metal catalysts, which results in higher local transport losses in the catalyst layers. In this paper, we use a hydrogen-pump limiting-current setup to explore the gas-phase transport losses through PEFC catalyst layers and various ga...

  13. Novel 3-Phase Inductive Fault Current Limiter

    Science.gov (United States)

    Kosa, Janos

    The paper describes the inductive three-phase fault current limiter. In this work I examine the novel arrangements of the perfect closed superconducting loop made of HTS wire. I applied one iron core with 3 limbs and special loops for uniform temperature of the superconducting wire. In this work I present the results of my experiments with this device. I present the static and dynamic measured results of this solution. It has got several advantages e. g. fast switching and less fault power for high-power electric machines. The advantage of the equipment is that in the case of single-phase short circuit the current will decrease in all the three phases. This can be an appropriate solution for high power machines. For example, in the case of high-power electric motor if there is a single-phase breaking or a single phase short circuit, we can decrease the current in the three phases.

  14. Current limitations and recommendations to improve testing ...

    Science.gov (United States)

    In this paper existing regulatory frameworks and test systems for assessing potential endocrine-active chemicals are described, and associated challenges discussed, along with proposed approaches to address these challenges. Regulatory frameworks vary somewhat across organizations, but all basically evaluate whether a chemical possesses endocrine activity and whether this activity can result in adverse outcomes either to humans or the environment. Current test systems include in silico, in vitro and in vivo techniques focused on detecting potential endocrine activity, and in vivo tests that collect apical data to detect possible adverse effects. These test systems are currently designed to robustly assess endocrine activity and/or adverse effects in the estrogen, androgen, and thyroid hormonal pathways; however, there are some limitations of current test systems for evaluating endocrine hazard and risk. These limitations include a lack of certainty regarding: 1)adequately sensitive species and life-stages, 2) mechanistic endpoints that are diagnostic for endocrine pathways of concern, and 3) the linkage between mechanistic responses and apical, adverse outcomes. Furthermore, some existing test methods are resource intensive in regard to time, cost, and use of animals. However, based on recent experiences, there are opportunities to improve approaches to, and guidance for existing test methods, and to reduce uncertainty. For example, in vitro high throughput

  15. [Male contraception - the current state of knowledge].

    Science.gov (United States)

    Zdrojewicz, Zygmynt; Kasperska, Karolina; Lewandowska, Marta

    2016-08-01

    Contraception is important from a health, psychological and socioeconomic point of view. Due to the fact that male-based contraceptive methods are mostly represented by condoms and vasectomy, researchers are working on the new solutions, which could let the men be more involved in a conscious family planning. In this review we will present the current state of knowledge on this subject. There is a lot going on in the field of hormonal contraception. Studies including testosterone, progestins, synthetic androgens and other derivatives are on a different stages of clinical trials and mostly demonstrate high efficacy rates. Recent discovers of Izumo and Juno proteins, essential for the fertilization process, give hope for an easily reversible, non-hormonal method. Researchers are also trying to interfere with the process of spermatogenesis using BRDT inhibitor - JQ1, or neutralize the sperm by injecting styrene maleic anhydride (SMA) into the lumen of the vas deferens. The other studies explore processes involved in proper sperm motility. A vaccine which induces an immune response to the reproductive system is also an interesting method. The latest research use ultrasound waves and mechanical device which blocks the patency of vas deferens. The aim of the study current state of knowledge male contraception. © 2016 MEDPRESS.

  16. Resistive-Type Fault Current Limiter

    Science.gov (United States)

    Martini, L.; Bocchi, M.; Angeli, G.

    Among the wide range of High-Temperature Superconducting (HTS) materials presently known Bismuth Strontium Calcium Copper Oxide (BSCCO) is a very suitable candidate for power applications either at low temperature (e.g. framework of a R&D national project, started focusing on a preliminary single-phase device, which was submitted to dielectric and short-circuit current testing. The first success paved the way for the finalization of the remaining two phases and the final result was a three-phase resistive-type 9 kV/3.4 MVA SFCL device, based on first generation (1G) BSCCO tapes that was installed in the S. Dionigi substation, belonging to the Italian utility A2A Reti Elettriche S.p.A. (A2A), in the Milan MV distribution grid. The in-field activity lasted for more than two years, demonstrating the SFCL capability to cope with the grid in every-day operating conditions. Moreover, at the end of the experimentation, the SFCL device was able to perform a true limitation during a three-phase fault, thereby becoming one of the first SFCL devices in the world (the first in Italy) installed in a real grid and to have limited a real short-circuit current.

  17. Primordial Germ Cells: Current Knowledge and Perspectives

    Directory of Open Access Journals (Sweden)

    Aleksandar Nikolic

    2016-01-01

    Full Text Available Infertility is a condition that occurs very frequently and understanding what defines normal fertility is crucial to helping patients. Causes of infertility are numerous and the treatment often does not lead to desired pregnancy especially when there is a lack of functional gametes. In humans, the primordial germ cell (PGC is the primary undifferentiated stem cell type that will differentiate towards gametes: spermatozoa or oocytes. With the development of stem cell biology and differentiation protocols, PGC can be obtained from pluripotent stem cells providing a new therapeutic possibility to treat infertile couples. Recent studies demonstrated that viable mouse pups could be obtained from in vitro differentiated stem cells suggesting that translation of these results to human is closer. Therefore, the aim of this review is to summarize current knowledge about PGC indicating the perspective of their use in both research and medical application for the treatment of infertility.

  18. Current knowledge of nocardiosis in teleost fish.

    Science.gov (United States)

    Maekawa, S; Yoshida, T; Wang, P-C; Chen, S-C

    2018-03-01

    Nocardia sp. is the causative agent of nocardiosis, a lethal granulomatous disease of the skin, muscle, and various inner tissues affecting various teleost and shellfish. Four species of Nocardia have been isolated from diseased fish and shellfish, namely Nocardia asteroides, Nocardia seriolae, Nocardia salmonicida and Nocardia crassostreae. Therefore, in fish aquaculture, nocardiosis has caused severe economic losses, especially in the Asian region. Considerable research has been performed, since the first report of identified Nocardia sp. in fish, to characterize Nocardia sp. and identify rapid detection techniques, immune response against infection and prophylactic approaches. In this review, the current state of knowledge about nocardiosis in fish has been presented, including the pathogenesis, diagnosis, host immune response and vaccine development. © 2018 John Wiley & Sons Ltd.

  19. Two limitations of our knowledge of quality

    OpenAIRE

    Reich, Johannes

    2016-01-01

    This article develops a quality notion that is complementary to the system notion. As a major consequence, it becomes clear why quality can be measured only to a certain extend based on the issues of validity and incompleteness. First, there is an inherent conflict between the applicability and validity of quality measures and second, quality considerations almost always refer to high-dimensional spaces with only sparse knowledge also known as "curse of dimensionality". The resulting gap of k...

  20. Current Knowledge on Cannabinoids in Oral Fluid

    Science.gov (United States)

    Lee, Dayong; Huestis, Marilyn A.

    2015-01-01

    Oral fluid (OF) is a new biological matrix for clinical and forensic drug testing, offering non-invasive and directly observable sample collection reducing adulteration potential, ease of multiple sample collections, lower biohazard risk during collection, recent exposure identification, and stronger correlation with blood than urine concentrations. Because cannabinoids are usually the most prevalent analytes in illicit drug testing, application of OF drug testing requires sufficient scientific data to support sensitive and specific OF cannabinoid detection. This review presents current knowledge on OF cannabinoids, evaluating pharmacokinetic properties, detection windows, and correlation with other biological matrices and impairment from field applications and controlled drug administration studies. In addition, on-site screening technologies, confirmatory analytical methods, drug stability, and effects of sample collection procedure, adulterants, and passive environmental exposure are reviewed. Delta-9-tetrahydrocannabinol OF concentrations could be > 1000 μg/L shortly after smoking, whereas minor cannabinoids are detected at 10-fold and metabolites at 1000-fold lower concentrations. OF research over the past decade demonstrated that appropriate interpretation of test results requires a comprehensive understanding of distinct elimination profiles and detection windows for different cannabinoids, which are influenced by administration route, dose, and drug use history. Thus, each drug testing program should establish cutoff criteria, collection/analysis procedures, and storage conditions tailored to its purposes. Building a scientific basis for OF testing is on-going, with continuing OF cannabinoids research on passive environmental exposure, drug use history, donor physiological conditions, and oral cavity metabolism needed to better understand mechanisms of cannabinoid OF disposition and expand OF drug testing applicability. PMID:23983217

  1. Current trends on knowledge-based systems

    CERN Document Server

    Valencia-García, Rafael

    2017-01-01

    This book presents innovative and high-quality research on the implementation of conceptual frameworks, strategies, techniques, methodologies, informatics platforms and models for developing advanced knowledge-based systems and their application in different fields, including Agriculture, Education, Automotive, Electrical Industry, Business Services, Food Manufacturing, Energy Services, Medicine and others. Knowledge-based technologies employ artificial intelligence methods to heuristically address problems that cannot be solved by means of formal techniques. These technologies draw on standard and novel approaches from various disciplines within Computer Science, including Knowledge Engineering, Natural Language Processing, Decision Support Systems, Artificial Intelligence, Databases, Software Engineering, etc. As a combination of different fields of Artificial Intelligence, the area of Knowledge-Based Systems applies knowledge representation, case-based reasoning, neural networks, Semantic Web and TICs used...

  2. Medicare Current Beneficiary Survey - Limited Data Set

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Medicare Current Beneficiary Survey (MCBS) is a continuous, multipurpose survey of a representative national sample of the Medicare population. There are two...

  3. Acute disseminated encephalomyelitis: current knowledge and open questions.

    Science.gov (United States)

    Steiner, Israel; Kennedy, Peter G E

    2015-10-01

    Acute disseminated encephalomyelitis (ADEM) is usually an acute, multi-focal, and monophasic immune-mediated disease of the central nervous system. The disorder is mainly a condition of the pediatric age group, but neurologists are also involved in the management of adult patients. The lack of defined diagnostic criteria for ADEM underlies the limited understanding of its epidemiology, etiology, pathogenesis, course, prognosis, therapy, as well as the association with, and distinction from, multiple sclerosis. The present review summarizes current knowledge and outlines unanswered questions the answers to which should be eventually provided through a synergistic combination of clinical and basic research.

  4. Cervical cancer: current knowledge, perception and associated ...

    African Journals Online (AJOL)

    Bivariate analyses were conducted to identify factors associated with knowledge and perception about cervical cancer. Results: Of all the interviews conducted, 89.1% were aware that cervical cancer is a life threatening situation, and 67.4% of the respondents knew that cervical cancer is linked to the virus, Human ...

  5. Current state of knowledge on Virilastacus species (Crustacea, Decapoda, Parastacidae

    Directory of Open Access Journals (Sweden)

    Erich H Rudolph

    2015-11-01

    Full Text Available The genus Virilastacus was created in 1991 to accommodate Parastacus araucanius Faxon, 1914. At present, Virilastacus comprises four burrowing species, three of which were described at the beginning of the XXI century, and biological knowledge about these species is mainly limited to taxonomic and distributional aspects. This review compiles published information about these species, together with other data available to the author in order to update the current state of biological knowledge and, in turn, to promote the conservation of these species. An upgraded diagnosis of the genus Virilastacus is provided, together with information related to each species with regard to: distinctive morphological traits, geographic distribution, habitat, burrow morphology, burrowing behavior, body size, sexual system, and state of conservation. Some aspects related to morphological adaptations to their burrowing life style, phylogenetic affinities and main threats to conservation are also discussed. It is concluded that biological knowledge about these four species is scarce and fragmentary; furthermore, they are currently under threat as a result of anthropogenic activities that are degrading and fragmenting their habitat.

  6. REVIEW OF CURRENT TRENDS IN SHAPING FINANCIAL KNOWLEDGE

    Directory of Open Access Journals (Sweden)

    Agata Gemzik-Salwach

    2012-04-01

    Full Text Available The activity of local government units requires them to constantly deepen the financial knowledge and competence of their employees. This article presents review of current trends in shaping financial knowledge of local government units in Poland. The first part of this paper shows trends concerning sources of gaining financial knowledge. The second part shows the most interesting areas of financial knowledge. The third part contains the review of the most popular financial knowledge sharing methods.

  7. Sleep bruxism: Current knowledge and contemporary management

    OpenAIRE

    Adrian U.J. Yap; Ai Ping Chua

    2016-01-01

    Bruxism is defined as the repetitive jaw muscle activity characterized by the clenching or grinding of teeth. It can be categorized into awake and sleep bruxism (SB). Frequent SB occurs in about 13% of adults. The exact etiology of SB is still unknown and probably multifactorial in nature. Current literature suggests that SB is regulated centrally (pathophysiological and psychosocial factors) and not peripherally (morphological factors). Cited consequences of SB include temporomandibular diso...

  8. Current Knowledge of Trichosporon spp. and Trichosporonosis

    Science.gov (United States)

    Colombo, Arnaldo L.; Padovan, Ana Carolina B.; Chaves, Guilherme M.

    2011-01-01

    Summary: Trichosporon spp. are basidiomycetous yeast-like fungi found widely in nature. Clinical isolates are generally related to superficial infections. However, this fungus has been recognized as an opportunistic agent of invasive infections, mostly in cancer patients and those exposed to invasive medical procedures. It is possible that the ability of Trichosporon strains to form biofilms on implanted devices, the presence of glucuronoxylomannan in their cell walls, and the ability to produce proteases and lipases are all factors likely related to the virulence of this genus and therefore may account for the progress of invasive trichosporonosis. Disseminated trichosporonosis has been increasingly reported worldwide and represents a challenge for both diagnosis and species identification. Phenotypic identification methods are useful for Trichosporon sp. screening, but only molecular methods, such as IGS region sequencing, allow the complete identification of Trichosporon isolates at the species level. Methods for the diagnosis of invasive trichosporonosis include PCR-based methods, Luminex xMAP technology, and, more recently, proteomics. Treating patients with trichosporonosis remains a challenge because of limited data on the in vitro and in vivo activities of antifungal drugs against clinically relevant species of the genus. Despite the mentioned limitations, the use of antifungal regimens containing triazoles appears to be the best therapeutic approach. PMID:21976604

  9. Current Knowledge on Genetic Biofortification in Lentil.

    Science.gov (United States)

    Kumar, Jitendra; Gupta, Debjyoti Sen; Kumar, Shiv; Gupta, Sanjeev; Singh, Narendra Pratap

    2016-08-24

    Micronutrient deficiency in the human body, popularly known as "hidden hunger", causes many health problems. It presently affects >2 billion people worldwide, especially in South Asia and sub-Saharan Africa. Biofortification of food crop varieties is one way to combat the problem of hidden hunger using conventional plant breeding and transgenic methods. Lentils are rich sources of protein, micronutrients, and vitamins including iron, zinc, selenium, folates, and carotenoids. Lentil genetic resources including germplasm and wild species showed genetic variability for these traits. Studies revealed that a single serving of lentils could provide a significant amount of the recommended daily allowance of micronutrients and vitamins for adults. Therefore, lentils have been identified as a food legume for biofortification, which could provide a whole food solution to the global micronutrient malnutrition. The present review discusses the current ongoing efforts toward genetic biofortification in lentils using classical breeding and molecular marker-assisted approaches.

  10. Sleep bruxism: Current knowledge and contemporary management

    Science.gov (United States)

    Yap, Adrian U.; Chua, Ai Ping

    2016-01-01

    Bruxism is defined as the repetitive jaw muscle activity characterized by the clenching or grinding of teeth. It can be categorized into awake and sleep bruxism (SB). Frequent SB occurs in about 13% of adults. The exact etiology of SB is still unknown and probably multifactorial in nature. Current literature suggests that SB is regulated centrally (pathophysiological and psychosocial factors) and not peripherally (morphological factors). Cited consequences of SB include temporomandibular disorders, headaches, tooth wear/fracture, implant, and other restoration failure. Chairside recognition of SB involves the use of subjective reports, clinical examinations, and trial oral splints. Definitive diagnosis of SB can only be achieved using electrophysiological tools. Pharmacological, psychological, and dental strategies had been employed to manage SB. There is at present, no effective treatment that “cures” or “stops” SB permanently. Management is usually directed toward tooth/restoration protection, reduction of bruxism activity, and pain relief. PMID:27656052

  11. Sleep bruxism: Current knowledge and contemporary management.

    Science.gov (United States)

    Yap, Adrian U; Chua, Ai Ping

    2016-01-01

    Bruxism is defined as the repetitive jaw muscle activity characterized by the clenching or grinding of teeth. It can be categorized into awake and sleep bruxism (SB). Frequent SB occurs in about 13% of adults. The exact etiology of SB is still unknown and probably multifactorial in nature. Current literature suggests that SB is regulated centrally (pathophysiological and psychosocial factors) and not peripherally (morphological factors). Cited consequences of SB include temporomandibular disorders, headaches, tooth wear/fracture, implant, and other restoration failure. Chairside recognition of SB involves the use of subjective reports, clinical examinations, and trial oral splints. Definitive diagnosis of SB can only be achieved using electrophysiological tools. Pharmacological, psychological, and dental strategies had been employed to manage SB. There is at present, no effective treatment that "cures" or "stops" SB permanently. Management is usually directed toward tooth/restoration protection, reduction of bruxism activity, and pain relief.

  12. Knowledge of limited health literacy at an academic health center.

    Science.gov (United States)

    Jukkala, Angela; Deupree, Joy P; Graham, Shannon

    2009-07-01

    Health care providers' awareness and knowledge of the impact that limited health literacy has on the health care system and the individual patient was measured. In addition, the usefulness of the Limited Literacy Impact Measure (LLIM) was examined. Two hundred forty providers and students attending a university-sponsored presentation on health literacy were invited to participate. Participants were most knowledgeable about the impact on patients and less knowledgeable about the impact on the health care system. Health care provider knowledge and awareness of limited health literacy continues to be a challenge. Educational programs developed for providers and patients are needed to address the health literacy crisis. Improving health literacy will improve health outcomes while reducing the use of unnecessary health care services.

  13. Awareness and current knowledge of breast cancer.

    Science.gov (United States)

    Akram, Muhammad; Iqbal, Mehwish; Daniyal, Muhammad; Khan, Asmat Ullah

    2017-10-02

    Breast cancer remains a worldwide public health dilemma and is currently the most common tumour in the globe. Awareness of breast cancer, public attentiveness, and advancement in breast imaging has made a positive impact on recognition and screening of breast cancer. Breast cancer is life-threatening disease in females and the leading cause of mortality among women population. For the previous two decades, studies related to the breast cancer has guided to astonishing advancement in our understanding of the breast cancer, resulting in further proficient treatments. Amongst all the malignant diseases, breast cancer is considered as one of the leading cause of death in post menopausal women accounting for 23% of all cancer deaths. It is a global issue now, but still it is diagnosed in their advanced stages due to the negligence of women regarding the self inspection and clinical examination of the breast. This review addresses anatomy of the breast, risk factors, epidemiology of breast cancer, pathogenesis of breast cancer, stages of breast cancer, diagnostic investigations and treatment including chemotherapy, surgery, targeted therapies, hormone replacement therapy, radiation therapy, complementary therapies, gene therapy and stem-cell therapy etc for breast cancer.

  14. Pneumococcal infections at Hajj: current knowledge gaps.

    Science.gov (United States)

    Ridda, Iman; King, Catherine; Rashid, Harunor

    2014-01-01

    Hajj attendance increases the risk of respiratory infections including pneumonia. Streptococcus pneumoniae is a frequently identified pathogen, found in about 10% of respiratory tract samples of symptomatic Hajj pilgrims; and at least 20% of these isolates are penicillin resistant. However, the burden of pneumococcal disease at Hajj is not precisely defined at serotypic level, and it is postulated that due to intense mixing of pilgrims the distribution of pneumococcal serotypes at Hajj could be different from pilgrims' country of origin or of Saudi Arabia. In Saudi Arabia, the most prevalent pneumococcal serotypes are 23F, 6B, 19F, 18C, 4, 14, and 19A, and 90% of the serotypes are covered by 13-valent pneumococcal conjugate vaccine (PCV-13) as well as 23-valent pneumococcal polysaccharide vaccine (PPV-23). However, due to lack of Hajj-specific data, the Saudi Arabian Ministry of Health has not yet recommended pneumococcal vaccine for pilgrims, and the immunisation recommendation and uptake vary greatly across countries. As at least one third of Hajj pilgrims are 'at risk' of pneumococcal disease either by virtue of age or pre-existing medical conditions, consideration should be given to vaccinating high risk pilgrims against pneumococcal disease. Other preventive measures such as smoking cessation, pollution reduction and vaccinations against influenza and pertussis should also be considered. Precisely defining the epidemiology of pneumococcal disease to identify an optimum vaccination schedule for Hajj pilgrims is a current research priority.

  15. Limiting current density and water dissociation in bipolar membranes

    NARCIS (Netherlands)

    Strathmann, H.; Krol, J.J.; Rapp, H.J.; Eigenberger, G.

    1997-01-01

    The behaviour of bipolar membranes in NaCl and Na2SO4 solutions is discussed. The membranes are characterized in terms of their limiting current densities. Below the limiting current density the electric current is carried by salt ions migrating from the transition region between the anion and the

  16. [Dioxins: current knowledge about health effects].

    Science.gov (United States)

    Wissing, M

    1998-09-01

    effects at the prevailing level of exposure. Nevertheless this hypothesis is currently unconfirmed by epidemiological studies. The implications of this scientific incertitude for the implementation of preventive measures are briefly discussed.

  17. Current Knowledge and Recent Advances in Marine Dinoflagellate Transcriptomic Research

    Directory of Open Access Journals (Sweden)

    Muhamad Afiq Akbar

    2018-02-01

    Full Text Available Dinoflagellates are essential components in marine ecosystems, and they possess two dissimilar flagella to facilitate movement. Dinoflagellates are major components of marine food webs and of extreme importance in balancing the ecosystem energy flux in oceans. They have been reported to be the primary cause of harmful algae bloom (HABs events around the world, causing seafood poisoning and therefore having a direct impact on human health. Interestingly, dinoflagellates in the genus Symbiodinium are major components of coral reef foundations. Knowledge regarding their genes and genome organization is currently limited due to their large genome size and other genetic and cytological characteristics that hinder whole genome sequencing of dinoflagellates. Transcriptomic approaches and genetic analyses have been employed to unravel the physiological and metabolic characteristics of dinoflagellates and their complexity. In this review, we summarize the current knowledge and findings from transcriptomic studies to understand the cell growth, effects on environmental stress, toxin biosynthesis, dynamic of HABs, phylogeny and endosymbiosis of dinoflagellates. With the advancement of high throughput sequencing technologies and lower cost of sequencing, transcriptomic approaches will likely deepen our understanding in other aspects of dinoflagellates’ molecular biology such as gene functional analysis, systems biology and development of model organisms.

  18. The Transition to High School: Current Knowledge, Future Directions

    Science.gov (United States)

    2011-01-01

    In the American educational system, school transitions are frequent and predictable, but they can disrupt student functioning across developmental domains. How students experience school transitions has been a focus of research for some time, but the high school transition has received less attention, and the limited research often focuses on a particular developmental domain (e.g., academics and socioemotional well-being) to the exclusion of a more integrated model. This review relies on life course theory to establish an organizational framework for interpreting and connecting the diffuse and sometimes disparate findings on the high school transition, including adolescent developmental trajectories and the influence of social ties, changing sociocultural contexts, and stratification systems. Conclusions identify aspects for future inquiry suggested by current knowledge and the tenets of the life course perspective. PMID:21966178

  19. Brown carbon in the cryosphere: Current knowledge and perspective

    Directory of Open Access Journals (Sweden)

    Guang-Ming Wu

    2016-03-01

    Full Text Available Recently, the light-absorbing organic carbon, i.e., brown carbon (BrC, has received an increasing attention, because they could significantly absorb the solar radiation in the range of short wavelengths rather than the purely scattering effect. BrC is ubiquitous in the troposphere. It could undergo long range transport within the atmospheric circulation. After the deposition on the surface of snow or ice in the cryospheric region, as the major light absorbing impurities with black carbon and dust, BrC could reduce the snow albedo and accelerate the glacier melting. In this context, this paper summarized the current knowledge of BrC (in aerosols and snow in the cryospheric regions including the Arctic, Antarctic, and Alpines. Although some works have been conducted in those region, the current dataset on the optical properties of BrC like Absorption Ångström Exponent (AAE and Mass Absorption Efficiency (MAE is still limited, which hampers stimulating an accurate evaluation of its climate effects. Especially in the Himalayas and Tibetan Plateau, where very limited information concerning BrC is available. Considering biomass burning as a dominant source of BrC, a large amount of emissions from biomass burning in South Asia could reach the Himalayas and Tibetan Plateau, where the climate effect of BrC merits more investigation in the future.

  20. Diuretics in pediatrics: Current knowledge and future prospects

    NARCIS (Netherlands)

    M.M.J. van der Vorst (Maria); M. Kist (Manfred); A.J. van der Heijden (Bert); J. Burggraaf (Jacobus)

    2006-01-01

    textabstractThis review summarizes current knowledge on the pharmacology, pharmacokinetics, pharmacodynamics, and clinical application of the most commonly used diuretics in children. Diuretics are frequently prescribed drugs in children. Their main indication is to reduce fluid overload in acute

  1. Maximum time-dependent space-charge limited diode currents

    Energy Technology Data Exchange (ETDEWEB)

    Griswold, M. E. [Tri Alpha Energy, Inc., Rancho Santa Margarita, California 92688 (United States); Fisch, N. J. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States)

    2016-01-15

    Recent papers claim that a one dimensional (1D) diode with a time-varying voltage drop can transmit current densities that exceed the Child-Langmuir (CL) limit on average, apparently contradicting a previous conjecture that there is a hard limit on the average current density across any 1D diode, as t → ∞, that is equal to the CL limit. However, these claims rest on a different definition of the CL limit, namely, a comparison between the time-averaged diode current and the adiabatic average of the expression for the stationary CL limit. If the current were considered as a function of the maximum applied voltage, rather than the average applied voltage, then the original conjecture would not have been refuted.

  2. Superconducting dc fault current limiter; Limiteur supraconducteur de courant continu

    Energy Technology Data Exchange (ETDEWEB)

    Cointe, Y

    2007-12-15

    Within the framework of the electric power market liberalization, DC networks have many interests compared to alternative ones, but their protections need to use new systems. Superconducting fault current limiters enable by an overstepping of the critical current to limit the fault current to a preset value, lower than the theoretical short-circuit current. For these applications, coated conductors offer excellent opportunities. We worked on the implementation of these materials and built a test bench. We carried out limiting experiments to estimate the quench homogeneity at various short-circuit parameters. An important point is the temperature measurement by deposited sensors on the ribbon, results are in good correlation with the theoretical models. Improved quench behaviours for temperatures close to the critical temperature have been confirmed. Our results enable to better understand the limitation mechanisms of coated conductors. (author)

  3. Current Levels of Salt Knowledge: A Review of the Literature

    Directory of Open Access Journals (Sweden)

    Rani Sarmugam

    2014-12-01

    Full Text Available High salt intake increases the risk of hypertension and cardiovascular diseases. Given the role of knowledge as a determinant of food intake, this paper aims to review the current levels of salt knowledge and the association between salt knowledge and dietary salt intake and salt-related dietary practices in the general population. Twenty two studies were included in the review. In general, the studies showed consumers were able to identify the health risks associated with high salt intake. However, knowledge of recommended daily intakes, understanding of the relationships between salt and sodium and foods that contribute most salt to the diet were poor. Four of the five studies which examined the relationships between salt knowledge and salt-related dietary practices reported significant associations. Two important gaps in the current literature were identified. First, there is a need for a robustly validated tool to examine salt knowledge and its impact on salt intake. Second, a comprehensive salt knowledge assessment should include assessment of procedural, as well as declarative, knowledge.

  4. Pedagogical content knowledge: Knowledge of pedagogy novice teachers in mathematics learning on limit algebraic function

    Science.gov (United States)

    Ma'rufi, Budayasa, I. Ketut; Juniati, Dwi

    2017-02-01

    Teacher is one of the key aspects of student's achievement. Teachers should master content material taught, how to teach it, and can interpret the students' thinking so that students easily understand the subject matter. This research was a qualitative research that aimed at describing profile of PCK's teachers in mathematics on limit algebraic functions in terms of the differences of teaching experience. Pedagogical Content Knowledge (PCK) and understanding of teachers is defined as involving the relationship between knowledge of teaching materials, how to transfer the subject matter, and the knowledge of students in mathematics on limit algebraic functions that the subject matter may be understood by students. The PCK components in this research were knowledge of subject matter, knowledge of pedagogy, and knowledge of students. Knowledge of pedagogy defines as knowledge and understanding of teachers about the planning and organization of the learning and teaching strategy of limit algebraic function. The subjects were two mathematics high school teachers who teach in class XI IPS. Data were collected through observation of learning during five meetings and interviews before and after the lesson continued with qualitative data analysis. Focus of this article was to describe novice teacher's knowledge of student in mathematics learning on limit algebraic function. Based on the results of the analysis of qualitative data the data concluded that novice teacher's knowledge of pedagogy in mathematics on limit algebraic function showed: 1) in teaching the definitions tend to identify prior knowledge of the student experience with the material to be studied, but not in the form of a problem, 2) in posing the questions tend to be monotonous non lead and dig, 3) in response to student questions preservice teachers do not take advantage of the characteristics or the potential of other students, 4) in addressing the problem of students, tend to use the drill approach and did

  5. Determining the Limiting Current Density of Vanadium Redox Flow Batteries

    Directory of Open Access Journals (Sweden)

    Jen-Yu Chen

    2014-09-01

    Full Text Available All-vanadium redox flow batteries (VRFBs are used as energy storage systems for intermittent renewable power sources. The performance of VRFBs depends on materials of key components and operating conditions, such as current density, electrolyte flow rate and electrolyte composition. Mass transfer overpotential is affected by the electrolyte flow rate and electrolyte composition, which is related to the limiting current density. In order to investigate the effect of operating conditions on mass transport overpotential, this study established a relationship between the limiting current density and operating conditions. First, electrolyte solutions with different states of charge were prepared and used for a single cell to obtain discharging polarization curves under various operating conditions. The experimental results were then analyzed and are discussed in this paper. Finally, this paper proposes a limiting current density as a function of operating conditions. The result helps predict the effect of operating condition on the cell performance in a mathematical model.

  6. Market potential of superconductor current limiters; Marktpotential von supraleitenden Strombegrenzern

    Energy Technology Data Exchange (ETDEWEB)

    Lakner, M.; Braun, D. [ABB Schweiz AG, Corporate Research, Baden-Daettwil (Switzerland); Schnyder, G.; Mauchle, P. [Schnyder Ingenieure AG, Huenenberg (Switzerland)

    2003-07-01

    This final report for the Swiss Federal Office of Energy describes the two concepts - 'resistive' and 'inductive' - used for Superconducting Fault Current Limiters (SCFCL) that utilise the transition from zero to finite resistance to limit short-circuit currents. The main advantages of SCFCL are compared to other current-limiting technologies: They can limit any type of prospective fault current, operate fail-safe, be self-triggered and self-restoring. Their main disadvantage - the cooling effort necessary - is also discussed. The application possibilities of SCFCL were investigated by simulating the impact on utility and industrial grids. Applications of SCFCL such as the coupling of medium-voltage grids and their use in series with a circuit-breaker on the secondary side of a substation transformer are discussed. It is also shown that, by using fault current limiters, considerable cost savings can be made, especially in connection with new installations or the extension of existing plants.

  7. Fault current limiter with solid-state circuit breakers

    Science.gov (United States)

    Bălan, H.; Neamț, L.; Buzdugan, M. I.; Varodi, T.; Pop, E.

    2016-08-01

    Switching of power circuit breakers is an important technical issue, especially at short circuit, since the fault current cause thermal and dynamic stresses, and the power quality worsens. Recently, the development of distributed renewable electricity induces the short circuit protection problematic because the distributed production of electric energy cause the transport networks to lose their radial character and disturbs the protective relays coordination. The modern technologies for power switching uses static fault current limiters, which offers a viable solution to remove the problems caused by large fault currents in the system. An appropriate design of the current limiting device reduces the thermal and dynamic stress and limits the fault current to a low value. The static switches are based on high power semiconductor devices that offer advantages compared to mechanical switches. Using a fault current limiter that minimizes the effect of distributed generation of electricity in a radial network on the co-ordination of protective relays is a solution to this problem in terms of switching speed and lifespan of power switches.

  8. Occupational Therapy in Preschools: A Synthesis of Current Knowledge

    Science.gov (United States)

    Jasmin, Emmanuelle; Gauthier, Anne; Julien, Marjorie; Hui, Caroline

    2018-01-01

    This paper presents a synthesis of current knowledge about occupational therapy in preschools (for 3-6 year olds) in order to provide a better understanding of this field of practice and to guide the implementation or programming of this service. In the literature, occupational therapy in preschools has been documented mainly in the USA. Results…

  9. Current knowledge and attitudes: Russian olive biology, ecology and management

    Science.gov (United States)

    Sharlene E. Sing; Kevin J. Delaney

    2016-01-01

    The primary goals of a two-day Russian olive symposium held in February 2014 were to disseminate current knowledge and identify data gaps regarding Russian olive biology and ecology, distributions, integrated management, and to ascertain the feasibility and acceptance of a proposed program for classical biological control of Russian olive. The symposium was...

  10. Marine aerosol production: a review of the current knowledge

    NARCIS (Netherlands)

    O'Dowd, C.D.; Leeuw, G. de

    2007-01-01

    The current knowledge in primary and secondary marine aerosol formation is reviewed. For primary marine aerosol source functions, recent source functions have demonstrated a significant flux of submicrometre particles down to radii of 20 nm. Moreover, the source functions derived from different

  11. Prophylaxis and therapeutic potential of ozone in buiatrics: Current knowledge.

    Science.gov (United States)

    Đuričić, Dražen; Valpotić, Hrvoje; Samardžija, Marko

    2015-08-01

    Ozone therapy has been in use since 1896 in the USA. As a highly reactive molecule, ozone may inactivate bacteria, viruses, fungi, yeasts and protozoans, stimulate the oxygen metabolism of tissue, treat diseases, activate the immune system, and exhibit strong analgesic activity. More recently, ozone has been used in veterinary medicine, particularly in buiatrics, but still insufficiently. Medical ozone therapy has shown effectiveness as an alternative to the use of antibiotics, which are restricted to clinical use and have been withdrawn from non-clinical use as in-feed growth promoters in animal production. This review is an overview of current knowledge regarding the preventive and therapeutic effects of ozone in ruminants for the treatment of puerperal diseases and improvement in their fertility. In particular, ozone preparations have been tested in the treatment of reproductive tract lesions, urovagina and pneumomovagina, metritis, endometritis, fetal membrane retention and mastitis, as well as in the functional restoration of endometrium in dairy cows and goats. In addition, the preventive use of the intrauterine application of ozone has been assessed in order to evaluate its effectiveness in improving reproductive efficiency in dairy cows. No adverse effects were observed in cows and goats treated with ozone preparations. Moreover, there is a lot of evidence indicating the advantages of ozone preparation therapy in comparison to the application of antibiotics. However, there are certain limitations on ozone use in veterinary medicine and buiatrics, such as inactivity against intracellular microbes and selective activity against the same bacterial species, as well as the induction of tissue inflammation through inappropriate application of the preparation. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Limiting beta of stellarators with no net current

    Energy Technology Data Exchange (ETDEWEB)

    Strauss, H.R.; Monticello, D.A.

    1981-01-01

    Using reduced nonlinear MHD equations, we find finite beta, resistive, l = 2 stellarator equilibria with no net current. We then investigate stability to low mode number internal MHD modes, and find beta limits comparable to tokamaks. Low shear equilibria appear to be substantially more stable than high shear.

  13. Transmission Level High Temperature Superconducting Fault Current Limiter

    Energy Technology Data Exchange (ETDEWEB)

    Stewart, Gary [SuperPower, Inc., Schenectady, NY (United States)

    2016-10-05

    The primary objective of this project was to demonstrate the feasibility and reliability of utilizing high-temperature superconducting (HTS) materials in a Transmission Level Superconducting Fault Current Limiter (SFCL) application. During the project, the type of high-temperature superconducting material used evolved from 1st generation (1G) BSCCO-2212 melt cast bulk high-temperature superconductors to 2nd generation (2G) YBCO-based high-temperature superconducting tape. The SFCL employed SuperPower's “Matrix” technology, that offers modular features to enable scale up to transmission voltage levels. The SFCL consists of individual modules that contain elements and parallel inductors that assist in carrying the current during the fault. A number of these modules are arranged in an m x n array to form the current-limiting matrix.

  14. Utility survey of requirements for a HTS fault current limiter

    DEFF Research Database (Denmark)

    Nielsen, Jan Nygaard; Jørgensen, P.; Østergaard, Jacob

    2000-01-01

    The application of superconducting fault current limiters (SFCL) in the electric utility sector will clearly dependent on to what extent the needs and requirements of electric utilities can be met by the ongoing development of SFCL technology. This paper considers a questionnaire survey of which...... needs and expectations the Danish electric utilities have to this new technology. A bus-tie application of SFCL in a distribution substation with three parallel-coupled transformers is discussed...

  15. TB and HIV in the Central African region: current knowledge and knowledge gaps

    NARCIS (Netherlands)

    Janssen, S.; Huson, M. A. M.; Bélard, S.; Stolp, S.; Kapata, N.; Bates, M.; van Vugt, M.; Grobusch, M. P.

    2014-01-01

    Reliable and comprehensive data on the HIV/AIDS and TB co-pandemics from Central Africa remain scarce. This systematic review provides a comprehensive overview on current and past research activities in the region and provides a basis for future research work to close knowledge gaps. The scientific

  16. Current research knowledge about adolescent victimization via the Internet.

    Science.gov (United States)

    Wolak, Janis; Ybarra, Michele L; Mitchell, Kimberly; Finkelhor, David

    2007-08-01

    We review current knowledge about adolescent Internet-mediated victimization, including Internet-initiated sex crimes in which offenders use the Internet to meet victims, unwanted online sexual solicitations, Internet harassment, and unwanted and wanted exposure to online pornography. Internet-initiated sex crimes have received considerable publicity, but the media stories have contributed to stereotypes that do not accurately portray adolescent Internet experience. Adults' concerns are valid but need to be supported with information that illuminates the real safety issues and targets the specific population of youth impacted.

  17. Epigenetics of Addiction: Current Knowledge, Challenges, and Future Directions.

    Science.gov (United States)

    Cecil, Charlotte A M; Walton, Esther; Viding, Essi

    2016-09-01

    Addiction to psychoactive substances is a debilitating condition underpinned by the interplay of genetic and environmental factors. At present, a key challenge for research is to delineate how, at a molecular level, these influences become "biologically embedded," contributing to the onset and persistence of addictive behaviors. Recently, epigenetic processes that regulate gene expression have emerged as a potential mechanism of interest. In this commentary, we discuss the relevance of epigenetics to addiction research, starting with the current state of knowledge, what challenges we have yet to overcome, and what the future may hold in terms of research methodology and translational potential.

  18. Azelaic acid in dermatological treatment – current state of knowledge

    Directory of Open Access Journals (Sweden)

    Radomir Reszke

    2016-09-01

    Full Text Available Azelaic acid (AZA is a naturally occurring substance produced by Malassezia furfur which exerts various effects on the skin. Azelaic acid has antibacterial, anti-inflammatory, keratolytic, comedolytic, sebostatic and tyrosinase-inhibiting properties. Topical application of AZA as 20% cream or 15% gel is a well-established therapeutic method in various common dermatoses, mainly acne vulgaris, rosacea and disorders associated with hyperpigmentation. Azelaic acid is used as a component of chemical peels as well. The paper summarizes the most relevant issues concerning AZA application in dermatological treatment based on current knowledge.

  19. TB and HIV in the Central African region: current knowledge and knowledge gaps.

    Science.gov (United States)

    Janssen, S; Huson, M A M; Bélard, S; Stolp, S; Kapata, N; Bates, M; van Vugt, M; Grobusch, M P

    2014-04-01

    Reliable and comprehensive data on the HIV/AIDS and TB co-pandemics from Central Africa remain scarce. This systematic review provides a comprehensive overview on current and past research activities in the region and provides a basis for future research work to close knowledge gaps. The scientific literature was searched for publications meeting the following search terms: "tuberculosis" or "HIV" or "acquired immunodeficiency syndrome", combined with "Central Africa", or the names of individual countries within the region. Original studies, reviews and case series were included, and a selection of relevant articles was made. Most research in the field of HIV and TB has been conducted in Cameroon, where the epidemics have been described fairly well. The Democratic Republic of Congo ranked second on the amount of publications, despite the civil wars over the past several decades. Very little has been published on HIV and TB in the other countries, possibly due to the poor infrastructure of health care systems, lack of scientific capacity building or shortage of laboratory equipment. Despite the relatively high burden of HIV and TB in the Central African region, the amount of research activities on these topics is limited. A better understanding of the co-epidemics in this region is urgently needed. The occurrence of opportunistic infections, treatment complications and drug resistance in TB and HIV need to be better described; the failure of public health systems needs to be understood, and research infrastructure needs to be developed. Only then will it be possible to turn the tide against the HIV and TB epidemics in this region.

  20. [In the light of current knowledge right ventricle].

    Science.gov (United States)

    Taçoy, Gülten; Cengel, Atiye

    2014-09-01

    There are important differences between left and right ventricle. Due to anatomical location and structural features, in daily clinical practice the right ventricle cannot be assessed easily as the left ventricle. Therefore, the right ventricle has remained in the background of the left ventricle. Recent clinical studies and advanced imaging modalities have demonstrated that right ventricle is decisive for survival particularly in patients with congenital heart disease, pulmonary hypertension and heart failure. Therefore, the detailed evaluation of the right ventricle has become necessary in current clinical practice. For this reason, in our review we aimed to examine the embryological development, anatomical structure, physiological, metabolic characteristics, responses to different pathological conditions, effects on arrhythmias, causes of failure and imaging modalities of the right ventricle in light of the current knowledge's.

  1. Correcting Acidosis during Hemodialysis: Current Limitations and a Potential Solution.

    Science.gov (United States)

    Tovbin, David; Sherman, Richard A

    2016-01-01

    The deleterious catabolic and pro-inflammatory effects of acidosis in hemodialysis (HD) patients and the importance of its correction for limiting mineral bone disease (MBD) are well known. Although oral base therapy could be a solution for correcting acidosis in HD patients, it increases their already enormous medication load and sodium intake; this approach is not used commonly. Therefore, we need to rely more on correcting acidosis during the HD procedure, which is difficult to achieve, in part, because HD is an intermittent therapy. The currently used fixed dialysate bicarbonate concentrations are associated with pre-HD acidosis and intra-dialytic alkalosis. We suggest that a decreasing dialysate bicarbonate concentration from an initially high concentration be considered as a means of correcting acidosis with limited intra-dialytic alkalosis. Some evidence, as well as theoretical considerations, supports such an approach. © 2015 Wiley Periodicals, Inc.

  2. Information and interaction Eddington, Wheeler, and the limits of knowledge

    CERN Document Server

    Rickles, Dean

    2017-01-01

    In this essay collection, leading physicists, philosophers, and historians attempt to fill the empty theoretical ground in the foundations of information and address the related question of the limits to our knowledge of the world. Over recent decades, our practical approach to information and its exploitation has radically outpaced our theoretical understanding - to such a degree that reflection on the foundations may seem futile. But it is exactly fields such as quantum information, which are shifting the boundaries of the physically possible, that make a foundational understanding of information increasingly important. One of the recurring themes of the book is the claim by Eddington and Wheeler that information involves interaction and putting agents or observers centre stage. Thus, physical reality, in their view, is shaped by the questions we choose to put to it and is built up from the information residing at its core. This is the root of Wheeler’s famous phrase “it from bit.” After reading the s...

  3. PRA: A PERSPECTIVE ON STRENGTHS, CURRENT LIMITATIONS, AND POSSIBLE IMPROVEMENTS

    Directory of Open Access Journals (Sweden)

    ALI MOSLEH

    2014-02-01

    Full Text Available Probabilistic risk assessment (PRA has been used in various technological fields to assist regulatory agencies, managerial decision makers, and systems designers in assessing and mitigating the risks inherent in these complex arrangements. Has PRA delivered on its promise? How do we gage PRA performance? Are our expectations about value of PRA realistic? Are there disparities between what we get and what we think we are getting form PRA and its various derivatives? Do current PRAs reflect the knowledge gained from actual events? How do we address potential gaps? These are some of the questions that have been raised over the years since the inception of the field more than forty years ago. This paper offers a brief assessment of PRA as a technical discipline in theory and practice, its key strengths and weaknesses, and suggestions on ways to address real and perceived shortcomings.

  4. Current knowledge, gaps and challenges in the Southern European Seas

    Science.gov (United States)

    Papathanassiou, Evangelos

    2015-04-01

    New knowledge advances our current understanding on the selection and application of the appropriate tools for assessing the state of the marine environment in the Southern European Seas (SES). Diminishing the lack of knowledge is a prerequisite for sound policy decisions. Although gaps and knowledge are fewer today, the health of marine and coastal ecosystems in the SES is under pressure and shows, in places, some signs of deterioration and declining quality. Overall, there is a lack of data accessibility and long time series in the SES, while in many cases poorly constrained processes cannot really support knowledge-based policy making (e.g. ecosystem functioning, climate change, fisheries management, etc.). New knowledge has to be produced and excellence must be promoted to support sustainable economic growth. At the same time, existing and new capacities have to be upgraded and increased in order to support sustainable convergence between SES countries. There are several gaps that have been identified and processes that have been poorly understood in the SES, mainly from research projects that have been working at basin level. The main research priorities that have been identified from the SeasERA Project for both, the Mediterranean and the Black Sea include: the climate change and its impacts, the hydrological cycle, the ventilation and the inter-basin coupling, the marine biodiversity and the provision of goods and services, the marine protected areas, the deep sea ecosystems, the biological invasions, the marine pollution and the ocean and human health, the renewable energy, the maritime transport, the fisheries and aquaculture activities and the biotechnology and the exploitation of marine resources for industrial application. More important, however, is the fact that the economic, the social and the scientific and the environmental challenges must be collectively tackled. They should have prioritisation and clear objectives as well as data sharing for

  5. Mach Probe and Limiter Current Measurements in the STOR-M Tokamak

    Science.gov (United States)

    Morelli, Jordan; Singh, Ajay; Xiao, Chijin; Hirose, Akira

    2001-10-01

    We report plasma flow measurements conducted with a 4-sided Mach probe and the limiter current in a segmented limiter in both ac and normal modes of operation in the STOR-M tokamak. The Mach probe was biased in the ion saturation region and revealed the radial profiles of the toroidal and poloidal velocity structure in the plasma edge region. It was reported previously, from microwave interferometer measurements, that while the current goes to zero there is still a finite plasma density in the device. There are efforts to explain the equilibrium of this plasma, but to the best of our knowledge these are the first independent measurements from two other diagnostics indicating the finite density in the device during the current reversal with negligible rotational transform. Short circuiting through a limiter may provide a mechanism for decelerating plasma loss due to toroidal drifts.

  6. CURRENT-VOLTAGE CURVES FOR TREATING EFFLUENT CONTAINING HEDP: DETERMINATION OF THE LIMITING CURRENT

    Directory of Open Access Journals (Sweden)

    T. Scarazzato

    2015-12-01

    Full Text Available Abstract Membrane separation techniques have been explored for treating industrial effluents to allow water reuse and component recovery. In an electrodialysis system, concentration polarization causes undesirable alterations in the ionic transportation mechanism. The graphic construction of the current voltage curve is proposed for establishing the value of the limiting current density applied to the cell. The aim of this work was to determine the limiting current density in an electrodialysis bench stack, the function of which was the treatment of an electroplating effluent containing HEDP. For this, a system with five compartments was used with a working solution simulating the rinse waters of HEDP-based baths. The results demonstrated correlation between the regions defined by theory and the experimental data.

  7. Autophagy in Drosophila: From Historical Studies to Current Knowledge

    Science.gov (United States)

    Mulakkal, Nitha C.; Nagy, Peter; Takats, Szabolcs; Tusco, Radu; Juhász, Gábor; Nezis, Ioannis P.

    2014-01-01

    The discovery of evolutionarily conserved Atg genes required for autophagy in yeast truly revolutionized this research field and made it possible to carry out functional studies on model organisms. Insects including Drosophila are classical and still popular models to study autophagy, starting from the 1960s. This review aims to summarize past achievements and our current knowledge about the role and regulation of autophagy in Drosophila, with an outlook to yeast and mammals. The basic mechanisms of autophagy in fruit fly cells appear to be quite similar to other eukaryotes, and the role that this lysosomal self-degradation process plays in Drosophila models of various diseases already made it possible to recognize certain aspects of human pathologies. Future studies in this complete animal hold great promise for the better understanding of such processes and may also help finding new research avenues for the treatment of disorders with misregulated autophagy. PMID:24949430

  8. Fault current limitation with HTc superconductors; Limitation de courant a partir de materiaux supraconducteurs HTc

    Energy Technology Data Exchange (ETDEWEB)

    Buzon, D.

    2002-09-15

    This report deals with the possibility of using high critical temperature (HTc) superconductors for current limitation. The transition from a superconductive to a high dissipative state could be used to limit inrush currents. This application of superconductivity is very attractive because it's an innovative device for electrical networks without any conventional equivalence at high voltage. This device would allow to improve the density of connections and the continuity of the electrical distribution. This study can be divided into two fields. The aim of the first one is to analyse the behaviour of different HTc superconductors for current limitation. We carried out experimental measurements to characterise those conductors during a nominal AC rating (measurements of losses) and during a fault setting. Particularly, a description of the transition in bulk textured YBCO samples near Tc was made of inhomogeneous transition of the device and to estimate its losses. Finally, a 1 kV / 100 A demonstrator made of 43 meanders of textured YBCO was tested at 90,5 K. Thermal gradients seem to be responsible of the altering of some of the samples. The other part of this study concerns the dynamic of the transition. Near Tc, our experiments showed that the transition is more homogeneous. Experimental measurements also showed the influence of thermal exchanges with the cryogenic surrounding on the transition. This point can be justified if the dissipated energy is locally concentrated. (author)

  9. Double storey three phase saturated cores fault current limiter

    Science.gov (United States)

    Wolfus, Y.; Nikulshin, Y.; Friedman, A.; Yeshurun, Y.

    2014-05-01

    A novel saturated-cores Fault-Current-Limiter (FCL) configuration is described. This FCL is based on two parallel planes of iron rectangular cores, on which three-phase coils are mounted and connected in series to the grid. Two DC coils are mounted in between the planes on perpendicular core limbs connecting the two AC planes. The DC coils are set to magnetically saturate the AC cores. The transition to three-dimensional, double-storey design enables handling three-phase symmetrical faults while offering better decoupling between the AC and DC circuits. At the same time, it shortens the AC limb lengths and enables deeper magnetic saturation levels in comparison to other saturated cores FCL designs. Hence, this FCL configuration exhibits lower insertion impedance and higher ratio of fault to nominal state impedance in comparison with other designs.

  10. Evolution and current development of Transversal Themes: possibilities and limits

    Directory of Open Access Journals (Sweden)

    Carlos Rosales López

    2015-02-01

    Full Text Available The aim of this study was to determine the characteristics of the evolution and current development of transversal themes in education, considering them basically as important social cuestions with great influence in the overall education of the student. Specifically it seeks to clarify the level of preparation and dedication of teachers and schools to teach them. To do this, legislation used in our country (organics laws and decrees curriculum were analyzed and also the contribution of outstanding educators, institutions and researchers. We analyzed the characteristics of transversal themes in the educational project and the teaching program, its development in the clasroom and its projection out of it through the help of family and community. Conclusions about their current status (possibilities and limitations are derived and future proposals are made on the improvement of initial and ongoing training of teachers, to increase their collegiate or cooperative work of planning, intervention and evaluation, increased media and counseling in use, the need for increased communication and collaboration with families and other community institutions.How to reference this articleRosales López, C. (2015. Evolución y desarrollo actual de los Temas Transversales: posibilidades y límites. Foro de Educación, 13(18, pp. 143-160. doi: http://dx.doi.org/10.14516/fde.2015.013.018.008

  11. LIFELONG LEARNING THROUGH SECOND LIFE: CURRENT TRENDS, POTENTIALS AND LIMITATIONS

    Directory of Open Access Journals (Sweden)

    Nil GOKSEL-CANBEK

    2011-08-01

    Full Text Available Lifelong Learning (LLL has been a remarkable response to people-centered educational demand of 21st century. In order to provide effective formal, non-formal, and informal learning, immersive educational activities undertaken throughout life should be aimed to create a learning society in which people can experience individual and collective learning with no constrains of time or location. The concept of lifelong learning within the context of distance immersive education encompasses diverse 3D activities. The three dimensional, Web-based structured activities supported by distance learning technologies can be viewed as interactive tools which foster LLL. In this perspective, Second Life (SL can be regarded as one of the learning simulation milieus that allow learners to participate in various educational LLL activities in individual or group forms. The following paper examines how SL, taking advantage of its simulative nature and the possibility for creative interaction among participants, which are also common in games, allows the learners to participate in immersive constructivist learning activities. The article will also touch on the current uses of SL as a tool for LLL, as well as its potentials for further development according to the current trends in adult education. Further, the authors will discuss its limitations and will make suggestions towards a more complete pedagogical use.

  12. Current floristic and phytogeographic knowledge of Mexican Bromeliaceae

    Directory of Open Access Journals (Sweden)

    Adolfo Espejo Serna

    1998-09-01

    Full Text Available A current floristic and phytogeographic knowledge of native Mexican Bromeliaceae is presented. There are 22 genera of Bromeliaceae recorded from the country that include 326 species. The genus Ursulaea with 2 species is endemic to Mexico, while Hechtia with 48 of its 50 species has its principal center of diversity in the country. Tillandsia (175 spp, Hechtia (48 spp and Pitcairnia (46 spp are the genera with the greatest number of species. We present a comparative analysis of Mexican Bromeliaceae with that of other American regions that have recently published accounts for the Family, particularly the Mesomerican area, Venezuela, Ecuador, and the Guianas. Our results led us to the conclusion that all these floras should be considered as distinct. We observe a progressive decrease of the Simpson index value related with the remoteness of the Mexican area. A general analysis of the species numbers of Mexican bromeliad genera shows a distinct preference of the species for coniferous and oak forests, followed by tropical caducifolious forests. There is also significant representation of the family in other vegetation types such as cloud forests and tropical perennifolious forests. Generally Mexican Bromeliaceae species have scarce and sparse populations and in many cases they inhabit cliffs, bluffs and scarps in restricted areas. Concerning the geographic distribution of Mexican genera, 77.27 % are neotropical, 4.54% are South American and the remainder are Mexican and Central American. The generic endemism is very low (4.54 %, even if we extend the country limits to Megamexico sensu Rzedowsi (1991 it reaches only 13.63 %. The family endemism at specific level reaches 63.07 %. There are not available data about a specific analysis of the conservation status of Mexican Bromeliaceae, but we can point out that a great number of taxa are only known from the type collection or at the most from the type locality. This can perhaps be attributed in part to

  13. Current parallel I/O limitations to scalable data analysis.

    Energy Technology Data Exchange (ETDEWEB)

    Mascarenhas, Ajith Arthur; Pebay, Philippe Pierre

    2011-07-01

    This report describes the limitations to parallel scalability which we have encountered when applying our otherwise optimally scalable parallel statistical analysis tool kit to large data sets distributed across the parallel file system of the current premier DOE computational facility. This report describes our study to evaluate the effect of parallel I/O on the overall scalability of a parallel data analysis pipeline using our scalable parallel statistics tool kit [PTBM11]. In this goal, we tested it using the Jaguar-pf DOE/ORNL peta-scale platform on a large combustion simulation data under a variety of process counts and domain decompositions scenarios. In this report we have recalled the foundations of the parallel statistical analysis tool kit which we have designed and implemented, with the specific double intent of reproducing typical data analysis workflows, and achieving optimal design for scalable parallel implementations. We have briefly reviewed those earlier results and publications which allow us to conclude that we have achieved both goals. However, in this report we have further established that, when used in conjuction with a state-of-the-art parallel I/O system, as can be found on the premier DOE peta-scale platform, the scaling properties of the overall analysis pipeline comprising parallel data access routines degrade rapidly. This finding is problematic and must be addressed if peta-scale data analysis is to be made scalable, or even possible. In order to attempt to address these parallel I/O limitations, we will investigate the use the Adaptable IO System (ADIOS) [LZL+10] to improve I/O performance, while maintaining flexibility for a variety of IO options, such MPI IO, POSIX IO. This system is developed at ORNL and other collaborating institutions, and is being tested extensively on Jaguar-pf. Simulation code being developed on these systems will also use ADIOS to output the data thereby making it easier for other systems, such as ours, to

  14. The spatial limitations of current neutral models of biodiversity.

    Directory of Open Access Journals (Sweden)

    Rampal S Etienne

    Full Text Available The unified neutral theory of biodiversity and biogeography is increasingly accepted as an informative null model of community composition and dynamics. It has successfully produced macro-ecological patterns such as species-area relationships and species abundance distributions. However, the models employed make many unrealistic auxiliary assumptions. For example, the popular spatially implicit version assumes a local plot exchanging migrants with a large panmictic regional source pool. This simple structure allows rigorous testing of its fit to data. In contrast, spatially explicit models assume that offspring disperse only limited distances from their parents, but one cannot as yet test the significance of their fit to data. Here we compare the spatially explicit and the spatially implicit model, fitting the most-used implicit model (with two levels, local and regional to data simulated by the most-used spatially explicit model (where offspring are distributed about their parent on a grid according to either a radially symmetric Gaussian or a 'fat-tailed' distribution. Based on these fits, we express spatially implicit parameters in terms of spatially explicit parameters. This suggests how we may obtain estimates of spatially explicit parameters from spatially implicit ones. The relationship between these parameters, however, makes no intuitive sense. Furthermore, the spatially implicit model usually fits observed species-abundance distributions better than those calculated from the spatially explicit model's simulated data. Current spatially explicit neutral models therefore have limited descriptive power. However, our results suggest that a fatter tail of the dispersal kernel seems to improve the fit, suggesting that dispersal kernels with even fatter tails should be studied in future. We conclude that more advanced spatially explicit models and tools to analyze them need to be developed.

  15. Current expertise location by exploiting the dynamics of knowledge

    Directory of Open Access Journals (Sweden)

    Josef Nozicka

    2012-10-01

    Full Text Available Systems for expertise location are either very expensive in terms of the costs of maintenance or they tend to become obsolete or incomplete during the time. This article presents a new approach to knowledge mapping/expertise location allowing reducing the costs of knowledge mapping by maintaining the accuracy of the knowledge map. The efficiency of the knowledge map is achieved by introducing the knowledge estimation measures analysing the dynamics of knowledge of company employees and their textual results of work. Finding an expert with most up-to date knowledge is supported by focusing publishing history analysis. The efficiency of proposed measures within various timeframes of publishing history is evaluated by evaluation method introduced within the article. The evaluation took place in the environment of a middle-sized software company allowing seeing directly a practical usability of the expertise location technique. The results form various implications deployment of knowledge map within the company.

  16. Simple voltage-controlled current source for wideband electrical bioimpedance spectroscopy: circuit dependences and limitations

    Science.gov (United States)

    Seoane, F.; Macías, R.; Bragós, R.; Lindecrantz, K.

    2011-11-01

    In this work, the single Op-Amp with load-in-the-loop topology as a current source is revisited. This circuit topology was already used as a voltage-controlled current source (VCCS) in the 1960s but was left unused when the requirements for higher frequency arose among the applications of electrical bioimpedance (EBI). The aim of the authors is not only limited to show that with the currently available electronic devices it is perfectly viable to use this simple VCCS topology as a working current source for wideband spectroscopy applications of EBI, but also to identify the limitations and the role of each of the circuit components in the most important parameter of a current for wideband applications: the output impedance. The study includes the eventual presence of a stray capacitance and also an original enhancement, driving with current the VCCS. Based on the theoretical analysis and experimental measurements, an accurate model of the output impedance is provided, explaining the role of the main constitutive elements of the circuit in the source's output impedance. Using the topologies presented in this work and the proposed model, any electronic designer can easily implement a simple and efficient current source for wideband EBI spectroscopy applications, e.g. in this study, values above 150 kΩ at 1 MHz have been obtained, which to the knowledge of the authors are the largest values experimentally measured and reported for a current source in EBI at this frequency.

  17. Current limitations and challenges in nanowaste detection, characterisation and monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Part, Florian; Zecha, Gudrun [Department of Water-Atmosphere-Environment, University of Natural Resources and Life Sciences, Institute of Waste Management, Muthgasse 107, 1190 Vienna (Austria); Causon, Tim [Department of Chemistry, Division of Analytical Chemistry, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna (Austria); Sinner, Eva-Kathrin [Department of Nanobiotechnology, Institute for Synthetic Bioarchitectures, University of Natural Resources and Life Sciences, Muthgasse 11/II, 1190 Vienna (Austria); Huber-Humer, Marion, E-mail: marion.huber-humer@boku.ac.at [Department of Water-Atmosphere-Environment, University of Natural Resources and Life Sciences, Institute of Waste Management, Muthgasse 107, 1190 Vienna (Austria)

    2015-09-15

    Highlights: • First review on detection of nanomaterials in complex waste samples. • Focus on nanoparticles in solid, liquid and gaseous waste samples. • Summary of current applicable methods for nanowaste detection and characterisation. • Limitations and challenges of characterisation of nanoparticles in waste. - Abstract: Engineered nanomaterials (ENMs) are already extensively used in diverse consumer products. Along the life cycle of a nano-enabled product, ENMs can be released and subsequently accumulate in the environment. Material flow models also indicate that a variety of ENMs may accumulate in waste streams. Therefore, a new type of waste, so-called nanowaste, is generated when end-of-life ENMs and nano-enabled products are disposed of. In terms of the precautionary principle, environmental monitoring of end-of-life ENMs is crucial to allow assessment of the potential impact of nanowaste on our ecosystem. Trace analysis and quantification of nanoparticulate species is very challenging because of the variety of ENM types that are used in products and low concentrations of nanowaste expected in complex environmental media. In the framework of this paper, challenges in nanowaste characterisation and appropriate analytical techniques which can be applied to nanowaste analysis are summarised. Recent case studies focussing on the characterisation of ENMs in waste streams are discussed. Most studies aim to investigate the fate of nanowaste during incineration, particularly considering aerosol measurements; whereas, detailed studies focusing on the potential release of nanowaste during waste recycling processes are currently not available. In terms of suitable analytical methods, separation techniques coupled to spectrometry-based methods are promising tools to detect nanowaste and determine particle size distribution in liquid waste samples. Standardised leaching protocols can be applied to generate soluble fractions stemming from solid wastes, while

  18. Communication: Relaxation-limited electronic currents in extended reservoir simulations

    Science.gov (United States)

    Gruss, Daniel; Smolyanitsky, Alex; Zwolak, Michael

    2017-10-01

    Open-system approaches are gaining traction in the simulation of charge transport in nanoscale and molecular electronic devices. In particular, "extended reservoir" simulations, where explicit reservoir degrees of freedom are present, allow for the computation of both real-time and steady-state properties but require relaxation of the extended reservoirs. The strength of this relaxation, γ, influences the conductance, giving rise to a "turnover" behavior analogous to Kramers turnover in chemical reaction rates. We derive explicit, general expressions for the weak and strong relaxation limits. For weak relaxation, the conductance increases linearly with γ and every electronic state of the total explicit system contributes to the electronic current according to its "reduced" weight in the two extended reservoir regions. Essentially, this represents two conductors in series—one at each interface with the implicit reservoirs that provide the relaxation. For strong relaxation, a "dual" expression-one with the same functional form-results, except now proportional to 1/γ and dependent on the system of interest's electronic states, reflecting that the strong relaxation is localizing electrons in the extended reservoirs. Higher order behavior (e.g., γ2 or 1/γ2) can occur when there is a gap in the frequency spectrum. Moreover, inhomogeneity in the frequency spacing can give rise to a pseudo-plateau regime. These findings yield a physically motivated approach to diagnosing numerical simulations and understanding the influence of relaxation, and we examine their occurrence in both simple models and a realistic, fluctuating graphene nanoribbon.

  19. Communication: Relaxation-limited electronic currents in extended reservoir simulations.

    Science.gov (United States)

    Gruss, Daniel; Smolyanitsky, Alex; Zwolak, Michael

    2017-10-14

    Open-system approaches are gaining traction in the simulation of charge transport in nanoscale and molecular electronic devices. In particular, "extended reservoir" simulations, where explicit reservoir degrees of freedom are present, allow for the computation of both real-time and steady-state properties but require relaxation of the extended reservoirs. The strength of this relaxation, γ, influences the conductance, giving rise to a "turnover" behavior analogous to Kramers turnover in chemical reaction rates. We derive explicit, general expressions for the weak and strong relaxation limits. For weak relaxation, the conductance increases linearly with γ and every electronic state of the total explicit system contributes to the electronic current according to its "reduced" weight in the two extended reservoir regions. Essentially, this represents two conductors in series-one at each interface with the implicit reservoirs that provide the relaxation. For strong relaxation, a "dual" expression-one with the same functional form-results, except now proportional to 1/γ and dependent on the system of interest's electronic states, reflecting that the strong relaxation is localizing electrons in the extended reservoirs. Higher order behavior (e.g., γ(2) or 1/γ(2)) can occur when there is a gap in the frequency spectrum. Moreover, inhomogeneity in the frequency spacing can give rise to a pseudo-plateau regime. These findings yield a physically motivated approach to diagnosing numerical simulations and understanding the influence of relaxation, and we examine their occurrence in both simple models and a realistic, fluctuating graphene nanoribbon.

  20. Beyond the current noise limit in imaging through turbulent medium.

    Science.gov (United States)

    Popowicz, Adam; Kurek, Aleksander; Pollo, Agnieszka; Smolka, Bogdan

    2015-05-15

    Shift-and-add is an approach employed to mitigate the phenomenon of resolution degradation in images acquired through a turbulent medium. Using this technique, a large number of consecutive short exposures is registered below the coherence time of the atmosphere or other blurring medium. The acquired images are shifted to the position of the brightest speckle and stacked together to obtain high resolution and high signal-to-noise frame. In this Letter, we present a highly efficient method for determination of frame shifts, even if in a single frame the object cannot be distinguished from the background noise. The technique utilizes our custom genetic algorithm, which iteratively evolves a set of image shifts. We used the maximal energy of stacked images as an objective function for shifts estimation and validate the efficiency of the method on simulated and real images of simple and complex sources. Obtained results confirmed that our proposed method allows for the recovery of spatial distribution of objects even only 2% brighter than their background. The presented approach extends significantly current limits of image reconstruction with the use of shift-and-add method. The applications of our algorithm include both the optical and the infrared imaging. Our method may be also employed as a digital image stabilizer in extremely low light level conditions in professional and consumer applications.

  1. The Limits of Knowledge Management in Contemporary Corporate Conditions

    Science.gov (United States)

    Garrick, John

    2014-01-01

    This paper draws on Jean-François Lyotard's (1984) seminal study "The Postmodern Condition: A Report on Knowledge" to reflect on two macro-level catastrophes: the global financial crisis (GFC) of 2009 (and its continuing effects throughout the Eurozone and elsewhere) and Fukushima. These two case studies probe aspects of these grand…

  2. Current knowledge of the aetiology of human tubal ectopic pregnancy

    Science.gov (United States)

    Shaw, J.L.V.; Dey, S.K.; Critchley, H.O.D.; Horne, A.W.

    2010-01-01

    BACKGROUND An ectopic pregnancy is a pregnancy which occurs outside of the uterine cavity, and over 98% implant in the Fallopian tube. Tubal ectopic pregnancy remains the most common cause of maternal mortality in the first trimester of pregnancy. The epidemiological risk factors for tubal ectopic pregnancy are well established and include: tubal damage as a result of surgery or infection (particularly Chlamydia trachomatis), smoking and in vitro fertilization. This review appraises the data to date researching the aetiology of tubal ectopic pregnancy. METHODS Scientific literature was searched for studies investigating the underlying aetiology of tubal ectopic pregnancy. RESULTS Existing data addressing the underlying cause of tubal ectopic pregnancy are mostly descriptive. There are currently few good animal models of tubal ectopic pregnancy. There are limited data explaining the link between risk factors and tubal implantation. CONCLUSIONS Current evidence supports the hypothesis that tubal ectopic pregnancy is caused by a combination of retention of the embryo within the Fallopian tube due to impaired embryo-tubal transport and alterations in the tubal environment allowing early implantation to occur. Future studies are needed that address the functional consequences of infection and smoking on Fallopian tube physiology. A greater understanding of the aetiology of tubal ectopic pregnancy is critical for the development of improved preventative measures, the advancement of diagnostic screening methods and the development of novel treatments. PMID:20071358

  3. Current status of knowledge on public-speaking anxiety.

    Science.gov (United States)

    Pull, Charles B

    2012-01-01

    This review examines the current knowledge on public-speaking anxiety, that is, the fear of speaking in front of others. This article summarizes the findings from previous review articles and describes new research findings on basic science aspects, prevalence rates, classification, and treatment that have been published between August 2008 and August 2011. Recent findings highlight the major aspects of psychological and physiological reactivity to public speaking in individuals who are afraid to speak in front of others, confirm high prevalence rates of the disorder, contribute to identifying the disorder as a possibly distinct subtype of social anxiety disorder (SAD), and give support to the efficacy of treatment programs using virtual reality exposure and Internet-based self-help. Public-speaking anxiety is a highly prevalent disorder, leading to excessive psychological and physiological reactivity. It is present in a majority of individuals with SAD and there is substantial evidence that it may be a distinct subtype of SAD. It is amenable to treatment including, in particular, new technologies such as exposure to virtual environments and the use of cognitive-behavioral self-help programs delivered on the Internet.

  4. Phocine Distemper Virus: Current Knowledge and Future Directions

    Directory of Open Access Journals (Sweden)

    Pádraig J. Duignan

    2014-12-01

    Full Text Available Phocine distemper virus (PDV was first recognized in 1988 following a massive epidemic in harbor and grey seals in north-western Europe. Since then, the epidemiology of infection in North Atlantic and Arctic pinnipeds has been investigated. In the western North Atlantic endemic infection in harp and grey seals predates the European epidemic, with relatively small, localized mortality events occurring primarily in harbor seals. By contrast, PDV seems not to have become established in European harbor seals following the 1988 epidemic and a second event of similar magnitude and extent occurred in 2002. PDV is a distinct species within the Morbillivirus genus with minor sequence variation between outbreaks over time. There is now mounting evidence of PDV-like viruses in the North Pacific/Western Arctic with serological and molecular evidence of infection in pinnipeds and sea otters. However, despite the absence of associated mortality in the region, there is concern that the virus may infect the large Pacific harbor seal and northern elephant seal populations or the endangered Hawaiian monk seals. Here, we review the current state of knowledge on PDV with particular focus on developments in diagnostics, pathogenesis, immune response, vaccine development, phylogenetics and modeling over the past 20 years.

  5. Phocine distemper virus: current knowledge and future directions.

    Science.gov (United States)

    Duignan, Pádraig J; Van Bressem, Marie-Françoise; Baker, Jason D; Barbieri, Michelle; Colegrove, Kathleen M; De Guise, Sylvain; de Swart, Rik L; Di Guardo, Giovanni; Dobson, Andrew; Duprex, W Paul; Early, Greg; Fauquier, Deborah; Goldstein, Tracey; Goodman, Simon J; Grenfell, Bryan; Groch, Kátia R; Gulland, Frances; Hall, Ailsa; Jensen, Brenda A; Lamy, Karina; Matassa, Keith; Mazzariol, Sandro; Morris, Sinead E; Nielsen, Ole; Rotstein, David; Rowles, Teresa K; Saliki, Jeremy T; Siebert, Ursula; Waltzek, Thomas; Wellehan, James F X

    2014-12-22

    Phocine distemper virus (PDV) was first recognized in 1988 following a massive epidemic in harbor and grey seals in north-western Europe. Since then, the epidemiology of infection in North Atlantic and Arctic pinnipeds has been investigated. In the western North Atlantic endemic infection in harp and grey seals predates the European epidemic, with relatively small, localized mortality events occurring primarily in harbor seals. By contrast, PDV seems not to have become established in European harbor seals following the 1988 epidemic and a second event of similar magnitude and extent occurred in 2002. PDV is a distinct species within the Morbillivirus genus with minor sequence variation between outbreaks over time. There is now mounting evidence of PDV-like viruses in the North Pacific/Western Arctic with serological and molecular evidence of infection in pinnipeds and sea otters. However, despite the absence of associated mortality in the region, there is concern that the virus may infect the large Pacific harbor seal and northern elephant seal populations or the endangered Hawaiian monk seals. Here, we review the current state of knowledge on PDV with particular focus on developments in diagnostics, pathogenesis, immune response, vaccine development, phylogenetics and modeling over the past 20 years.

  6. Effect of recovery time of fault current limiter on over current from distributed generator in micro grid after voltage sag

    Directory of Open Access Journals (Sweden)

    Daisuke Iioka

    2016-01-01

    Full Text Available This paper describes an effect of recovery time of fault current limiter on over current from a micro grid system which is interconnected to a power distribution system. We have assumed that the semi-conductor type fault current limiter is installed between the micro grid system with the synchronous generator and the power distribution system, measured the over current after a voltage sag occurrence in the power distribution system and a recovery of fault current limiter by experiments in our laboratory. Finally, it was found that the introduction of recovery time for fault current limiter after voltage sag is useful for suppressing the over current from the distributed generator.

  7. Knowledge Management in healthcare libraries: the current picture.

    Science.gov (United States)

    Hopkins, Emily

    2017-06-01

    Knowledge management has seen something of a resurgence in attention amongst health librarians recently. Of course it has never ceased to exist, but now many library staff are becoming more involved in organisational knowledge management, and positioning themselves as key players in the sphere. No single model of knowledge management is proliferating, but approaches that best fit the organisation's size, structure and culture, and a blending of evidence based practice and knowledge sharing. Whatever it is called and whatever models are used, it's clear that for librarians and information professionals, the importance of putting knowledge and evidence into practice, sharing knowledge well and capturing it effectively, are still what we will continue to do. © 2017 Health Libraries Group.

  8. Trends and current status of indigenous knowledge among the ...

    African Journals Online (AJOL)

    Through this experiential co-adaptation the Turkana people have accumulated a wealth of indigenous knowledge and established institutions that have helped them to cope with their fragile environment. However, not much of this knowledge has been used in the design and implementation of development initiatives.

  9. Subclinical hypothyroidism in childhood - current knowledge and open issues.

    Science.gov (United States)

    Salerno, Mariacarolina; Capalbo, Donatella; Cerbone, Manuela; De Luca, Filippo

    2016-12-01

    Subclinical hypothyroidism is defined as serum levels of TSH above the upper limit of the reference range, in the presence of normal concentrations of total T4 or free T4. This biochemical profile might be an indication of mild hypothyroidism, with a potential increased risk of metabolic abnormalities and cardiovascular disease recorded among adults. Whether subclinical hypothyroidism results in adverse health outcomes among children is a matter of debate and so management of this condition remains challenging. Mild forms of untreated subclinical hypothyroidism do not seem to be associated with impairments in growth, bone health or neurocognitive outcome. However, ongoing scientific investigations have highlighted the presence of subtle proatherogenic abnormalities among children with modest elevations in their TSH levels. Although current findings are insufficient to recommend levothyroxine treatment for all children with mild asymptomatic forms of subclinical hypothyroidism, they highlight the potential need for assessment of cardiovascular risk among children with this condition. Increased understanding of the early metabolic risk factors associated with subclinical hypothyroidism in childhood will help to improve the management of affected individuals.

  10. On Dynamic Range Limitations of CMOS Current Conveyors

    DEFF Research Database (Denmark)

    Bruun, Erik

    1999-01-01

    This paper is concerned with the dynamic range of continuous time CMOS current mode circuits. As a representative current mode device a class AB current conveyor is examined. First, the voltage input range of the high impedance Y input is investigated. Next, the current input range of the low...... impedance X input is investigated. It is compared to the thermal noise in the X to Z signal path in order to evaluate the dynamic range, and the dependencies of the dynamic range on the supply voltage and the transistor lay-out is derived, both for the situation where the conveyor is used over a narrow...... frequency band and for the situation where the conveyor is used over the full bandwidth achievable. Finally, the optimisation of the current input range is related to the distortion characteristics and it is pointed out that to a first order approximation the distortion is independent of the current range....

  11. Colostomy irrigation: current knowledge and practice of WOC nurses.

    Science.gov (United States)

    Cobb, Martha D; Grant, Marcia; Tallman, Nancy J; Wendel, Christopher S; Colwell, Janice; McCorkle, Ruth; Krouse, Robert S

    2015-01-01

    This study builds on the authors' previous studies that demonstrate that persons living with a colostomy who practice colostomy irrigation (CI) experience quality-of-life benefits. Studies also reveal that patients may not be taught about CI. The purpose of this study was to determine current knowledge, attitudes, and practices of WOC nurses on CI. The target population was ostomy nurses who were members of the Wound, Ostomy and Continence Nurse's Society. Nine hundred eighty-five nurses out of a possible pool of 4191 members responded, providing a response rate of 24%. Their average age was 53 years (range, 25-79 years). Respondents averaged 12 years' experience as a WOC nurse (range, 1-40 years) and 90% (n = 875) were certified. Participants practiced in a variety of settings, including acute and long-term care facilities, home health, and ambulatory clinics. They saw an average of 37 ± 60.5 (mean ± SD) ostomy patients per year (range, 0-1100). A 1-time online survey (SurveyMonkey) of members of the Wound, Ostomy and Continence Nurses (WOCN) Society was conducted. In addition to demographic and educational information, questions also included (1) CI advantages and disadvantages; (2) CI content routinely taught; (3) challenges in assisting patients to learn CI; and (4) where preparation was received for teaching this procedure. Nurses were asked whether they believe CI is evidence-based. More than half identified irrigation as an evidence-based practice (59%), but half indicated they do not routinely teach CI. Multiple factors correlated with nurses' decisions to teach CI, including years of experience (P = .03), specific CI education (P < .001), and considering the intervention evidence-based (P < .001). Factors influencing CI instruction are multifactorial; they include nurses' attitudes, experience base, education, medical indications, setting characteristics, and patient interest and physical abilities. Education on this procedure is urgently needed for

  12. Knowledge visualization currents from text to art to culture

    CERN Document Server

    Marchese, Francis T

    2012-01-01

    Presents the state of the art in visualization research and development Highlights research developing at key intersections with other disciplines and its applicability to addressing complex real-world problems Discusses how visualization researchers are addressing complex issues of representation in knowledge, art, and culture

  13. Injection-limited electron current in a methanofullerene

    NARCIS (Netherlands)

    Duren, J.K.J. van; Mihailetchi, V.D.; Blom, P.W.M.; Woudenbergh, T. van; Hummelen, J.C.; Rispens, M.T.; Janssen, R.A.J.; Wienk, M.M.

    2003-01-01

    The dark current of bulk-heterojunction photodiodes consisting of a blend of a methanofullerene (PCBM) as n-type electron acceptor and a dialkoxy-(p-phenylene vinylene) (OC1C10-PPV) as a p-type electron donor sandwiched between electrodes with different work functions has been investigated. With

  14. Birds of Pernambuco: Current state of ornithological knowledge

    Directory of Open Access Journals (Sweden)

    Gilmar Beserra de Farias

    2009-09-01

    Full Text Available An analysis of the present state of ornithological knowledge is required for the guidance of researchers in their future investigations. This work provides a survey of literature describing the development of ornithological research in the state. Between 1880 and 2008, many lists were organized, which contributed towards the systematization of the knowledge about Pernambuco’s birds. Out if the 535 species recorded, 49 are found in marine environments or wetlands, 450 occur in the Atlantic Rainforest, and 270 reside in the semi-arid Caatinga. We suggest that studies on the birds of the Caatinga are most important and should be prioritized at present, in addition to effective actions for the conservation of endemic species and of species under risk of extinction.

  15. Current status of nuclear medicine in chronic airflow limitation

    Energy Technology Data Exchange (ETDEWEB)

    Clarke, S.W.; Agnew, J.E.

    1987-06-01

    Radionuclide imaging, quite apart from its role in the diagnosis of pulmonary embolism, offers information about the distribution of ventilatory and perfusion abnormalities within the lung. The extent of ventilatory abnormality seen can be related to the severity of airways obstruction as assessed spirometrically, whilst abnormalities in the matching of perfusion to ventilation can be related to the severity of hypoxaemia in patients with chronic airflow limitation. Clearance of mucus from the lungs of patients with chronic mucus hypersection may be assessed by following the clearance rate of insoluble radioaerosol particles; by such means the relative contributions of mucociliary transport and of cough to the overall clearance can be observed. Clearance is often severely impaired in patients with airways obstruction; the radioaerosol technique can be used to determine the effects of drug or physiotherapy treatment. Chronic airflow limitation leading to hypoxaemia can be associated with pulmonary artery hypertension and right ventricular hypertrophy - this may be investigated noninvasively by a radionuclide test of right ventricular ejection fraction.

  16. Genetic improvement of brewer's yeast: current state, perspectives and limits.

    Science.gov (United States)

    Saerens, Sofie M G; Duong, C Thuy; Nevoigt, Elke

    2010-05-01

    Brewer's yeast strain optimisation may lead to a more efficient beer production process, better final quality or healthier beer. However, brewer's yeast genetic improvement is very challenging, especially true when it comes to lager brewer's yeast (Saccharomyces pastorianus) which contributes to 90% of the total beer market. This yeast is a genetic hybrid and allopolyploid. While early studies applying traditional genetic approaches encountered many problems, the development of rational metabolic engineering strategies successfully introduced many desired properties into brewer's yeast. Recently, the first genome sequence of a lager brewer's strain became available. This has opened the door for applying advanced omics technologies and facilitating inverse metabolic engineering strategies. The latter approach takes advantage of natural diversity and aims at identifying and transferring the crucial genetic information for an interesting phenotype. In this way, strains can be optimised by introducing "natural" mutations. However, even when it comes to self-cloned strains, severe concerns about genetically modified organisms used in the food and beverage industry are still a major hurdle for any commercialisation. Therefore, research efforts will aim at developing new sophisticated screening methods for the isolation of natural mutants with the desired properties which are based on the knowledge of genotype-phenotype linkage.

  17. Achievements and Limits of Current Medical Therapy of Glaucoma.

    Science.gov (United States)

    Kalouda, Pelagia; Keskini, Christina; Anastasopoulos, Eleftherios; Topouzis, Fotis

    2017-01-01

    Prescribing medical therapy for the treatment of glaucoma can be a complex process since many parameters should be taken into consideration regarding its achievements and limits. Today, a variety of options, including multiple drug classes and multiple agents within classes, are available to the clinician, but caution should be given to their side effects and contraindications. Glaucoma patients with preexisting ocular surface disease should be treated with caution, and preferably with preservative-free formulations, as there is an increased risk for symptom deterioration. The development and use of fixed-combination therapies has reduced the preservative-related side effects that threaten patient adherence and has minimized the washout effect of multiple instillations. Adherence to medical treatment is not only crucial to its efficacy but also to its cost-effectiveness. Further factors to consider are that there are patients who are nonresponders to treatment, and also that the target intraocular pressure (IOP) cannot be reached in all patients, regardless of the response to treatment. The progression of damage can occur even under maximum medical treatment or maximally tolerated medical treatment, and regardless of whether low IOP levels are reached. Furthermore, there is some conflict between medical treatment and quality of life due to long-term everyday use and to side effects of treatment. New molecules and new delivery systems are being investigated to open new horizons in glaucoma management. Although the general rule is to initiate glaucoma management with medical treatment, the limits of medical therapy should be considered to identify those patients in need of surgical management. © 2017 S. Karger AG, Basel.

  18. Fighting Sharka in Peach: Current Limitations and Future Perspectives

    Directory of Open Access Journals (Sweden)

    Marco Cirilli

    2016-08-01

    Full Text Available Sharka, caused by Plum Pox Virus (PPV, is by far the most important infectious disease of peach [P. persica (L. Batsch] and other Prunus species. The progressive spread of the virus in many important growing areas throughout Europe poses serious issues to the economic sustainability of stone fruit crops, peach in particular. The adoption of internationally agreed-upon rules for diagnostic tests, strain-specific monitoring schemes and spatial-temporal modeling of virus spread, are all essential for a more effective sharka containment. The EU regulations on nursery activity should be modified based on the zone delimitation of PPV presence, limiting open-field production of propagation materials only to virus-free areas. Increasing the efficiency of preventive measures should be augmented by the short-term development of resistant cultivars. Putative sources of resistance/tolerance have been recently identified in peach germplasm, although the majority of novel resistant sources to PPV-M have been found in almond. However, the complexity of introgression from related-species imposes the search for alternative strategies. The use of genetic engineering, particularly RNAi-based approaches, appears as one of the most promising perspectives to introduce a durable resistance to PPV in peach germplasm, notwithstanding the well-known difficulties of in vitro plant regeneration in this species. In this regard, rootstock transformation to induce RNAi-mediated systemic resistance to PPV would avoid the transformation of numerous commercial cultivars, and may alleviate consumer resistance to the use of GM plants.

  19. Fighting Sharka in Peach: Current Limitations and Future Perspectives

    Science.gov (United States)

    Cirilli, Marco; Geuna, Filippo; Babini, Anna R.; Bozhkova, Valentina; Catalano, Luigi; Cavagna, Beniamino; Dallot, Sylvie; Decroocq, Véronique; Dondini, Luca; Foschi, Stefano; Ilardi, Vincenza; Liverani, Alessandro; Mezzetti, Bruno; Minafra, Angelantonio; Pancaldi, Marco; Pandolfini, Tiziana; Pascal, Thierry; Savino, Vito N.; Scorza, Ralph; Verde, Ignazio; Bassi, Daniele

    2016-01-01

    Sharka, caused by Plum Pox Virus (PPV), is by far the most important infectious disease of peach [P. persica (L.) Batsch] and other Prunus species. The progressive spread of the virus in many important growing areas throughout Europe poses serious issues to the economic sustainability of stone fruit crops, peach in particular. The adoption of internationally agreed-upon rules for diagnostic tests, strain-specific monitoring schemes and spatial–temporal modeling of virus spread, are all essential for a more effective sharka containment. The EU regulations on nursery activity should be modified based on the zone delimitation of PPV presence, limiting open-field production of propagation materials only to virus-free areas. Increasing the efficiency of preventive measures should be augmented by the short-term development of resistant cultivars. Putative sources of resistance/tolerance have been recently identified in peach germplasm, although the majority of novel resistant sources to PPV-M have been found in almond. However, the complexity of introgression from related-species imposes the search for alternative strategies. The use of genetic engineering, particularly RNA interference (RNAi)-based approaches, appears as one of the most promising perspectives to introduce a durable resistance to PPV in peach germplasm, notwithstanding the well-known difficulties of in vitro plant regeneration in this species. In this regard, rootstock transformation to induce RNAi-mediated systemic resistance would avoid the transformation of numerous commercial cultivars, and may alleviate consumer resistance to the use of GM plants. PMID:27625664

  20. Current applications and limitations of surgical treatments for movement disorders.

    Science.gov (United States)

    Krack, Paul; Martinez-Fernandez, Raul; Del Alamo, Marta; Obeso, Jose A

    2017-01-01

    Functional neurosurgery for the treatment of both psychiatric and neurological disorders has been performed regularly since the 1940s. However, misuse in the early days and the appearance of effective medical treatments, such as levodopa and neuroleptic drugs, greatly reduced surgical approaches over several decades. The development of a comprehensive model of basal ganglia pathophysiology in the 1990s facilitated the resurgence of functional neurosurgery, mainly for the treatment of levodopa-related motor complications in Parkinson's disease. This led first to the re-emergence of posteroventral pallidotomy and subsequently to deep brain stimulation. Thirty years on from this turning point, we find ourselves looking at a new scenario. Although deep brain stimulation is accepted worldwide and technical advances continue to improve this therapy, new questions and challenges such as long-term benefits and optimal targeting have emerged. In addition, new nonincisional tools used to perform ablative treatments, such as high-intensity focused ultrasound and gamma-knife, are challenging classical reluctance to therapeutic lesioning, and it remains to be determined how these approaches will fit into the array of movement disorder treatments. This review discusses the current clinical state of the art of functional neurosurgery in the treatment of Parkinson's disease, tremor, and dystonia. © 2017 International Parkinson and Movement Disorder Society. © 2017 International Parkinson and Movement Disorder Society.

  1. A Systematic Review of Athletes' and Coaches' Nutrition Knowledge and Reflections on the Quality of Current Nutrition Knowledge Measures.

    Science.gov (United States)

    Trakman, Gina L; Forsyth, Adrienne; Devlin, Brooke L; Belski, Regina

    2016-09-16

    Nutrition knowledge can influence dietary choices and impact on athletic performance. Valid and reliable measures are needed to assess the nutrition knowledge of athletes and coaches. (1) To systematically review the published literature on nutrition knowledge of adult athletes and coaches and (2) to assess the quality of measures used to assess nutrition knowledge. MEDLINE, CINAHL, SPORTDiscuss, Web of Science, and SCOPUS. 36 studies that provided a quantitative measure of nutrition knowledge and described the measurement tool that was used were included. Participant description, questionnaire description, results (mean correct and responses to individual items), study quality, and questionnaire quality. All studies were of neutral quality. Tools used to measure knowledge did not consider health literacy, were outdated with regards to consensus recommendations, and lacked appropriate and adequate validation. The current status of nutrition knowledge in athletes and coaches is difficult to ascertain. Gaps in knowledge also remain unclear, but it is likely that energy density, the need for supplementation, and the role of protein are frequently misunderstood. Previous reports of nutrition knowledge need to be interpreted with caution. A new, universal, up-to-date, validated measure of general and sports nutrition knowledge is required to allow for assessment of nutrition knowledge.

  2. A Systematic Review of Athletes’ and Coaches’ Nutrition Knowledge and Reflections on the Quality of Current Nutrition Knowledge Measures

    Directory of Open Access Journals (Sweden)

    Gina L. Trakman

    2016-09-01

    Full Text Available Context: Nutrition knowledge can influence dietary choices and impact on athletic performance. Valid and reliable measures are needed to assess the nutrition knowledge of athletes and coaches. Objectives: (1 To systematically review the published literature on nutrition knowledge of adult athletes and coaches and (2 to assess the quality of measures used to assess nutrition knowledge. Data Sources: MEDLINE, CINAHL, SPORTDiscuss, Web of Science, and SCOPUS. Study Selection: 36 studies that provided a quantitative measure of nutrition knowledge and described the measurement tool that was used were included. Data extraction: Participant description, questionnaire description, results (mean correct and responses to individual items, study quality, and questionnaire quality. Data synthesis: All studies were of neutral quality. Tools used to measure knowledge did not consider health literacy, were outdated with regards to consensus recommendations, and lacked appropriate and adequate validation. The current status of nutrition knowledge in athletes and coaches is difficult to ascertain. Gaps in knowledge also remain unclear, but it is likely that energy density, the need for supplementation, and the role of protein are frequently misunderstood. Conclusions: Previous reports of nutrition knowledge need to be interpreted with caution. A new, universal, up-to-date, validated measure of general and sports nutrition knowledge is required to allow for assessment of nutrition knowledge.

  3. Cancer Treatment-Related Cardiotoxicity: Understanding the Current State of Knowledge and Developing Future Research Priorities

    Science.gov (United States)

    Cancer Treatment-Related Cardiotoxicity: Understanding the Current State of Knowledge and Developing Future Research Priorities, a 2013 workshop sponsored by the Epidemiology and Genomics Research Program.

  4. Sugarcane Flood Tolerance: Current Limits and Future Prospects

    Energy Technology Data Exchange (ETDEWEB)

    Glaz, Barry; Gilbert, Robert

    2010-01-08

    Sugarcane flood tolerance is discussed in this presentation. Related issues are looked at from four perspectives – various limits, physiological and morphological changes, future gains speculations and possible ecological and hydrological applications. Sugarcane flood tolerance and yield changes are presented on several field experiments during the crop various growth phases – (1) after planting with furrow open and with furrow closed, (2) during summer growth and (3) prior to harvest. It is documented that flood or shallow water-table depth do not affect photosynthesis, stomatal conductance and transpiration. It is also documented that roots of all 40 sugarcane genotypes tested in Florida had aerenchyma, while stalks form aerenchyma after being flooded. However, only some genotypes form aerenchyma in stalks without exposure to flood; this provides extra flood tolerance. While it is still a theory, it seems that sugarcane root growth is decreased when roots must grow into water. However, sugarcane roots appear to meet the needs of the plant when flooded for up to 2 weeks. It is concluded that most commercial sugarcane cultivars in Florida can tolerate floods for 1 to 2 weeks and that sugarcane has physiological and morphological traits that allow it to respond well to short-duration floods, while continuous shallow water tables are more harmful to sugarcane than periodic flooding. Given these facts, new strategy of storing water on sugarcane fields is proposed - field A could be flooded for 1-2 weeks, then drained to the field B which would be flooded for 1-2 weeks, then drained to the field C, etc. Research should focus on extending this flood period duration, so new strategies for ecological and hydrological application could be pursued further.

  5. Surgical strategy for bile duct cancer: Advances and current limitations

    Science.gov (United States)

    Akamatsu, Nobuhisa; Sugawara, Yasuhiko; Hashimoto, Daijo

    2011-01-01

    The aim of this review is to describe recent advances and topics in the surgical management of bile duct cancer. Radical resection with a microscopically negative margin (R0) is the only way to cure cholangiocarcinoma and is associated with marked survival advantages compared to margin-positive resections. Complete resection of the tumor is the surgeon’s ultimate aim, and several advances in the surgical treatment for bile duct cancer have been made within the last two decades. Multidetector row computed tomography has emerged as an indispensable diagnostic modality for the precise preoperative evaluation of bile duct cancer, in terms of both longitudinal and vertical tumor invasion. Many meticulous operative procedures have been established, especially extended hepatectomy for hilar cholangiocarcinoma, to achieve a negative resection margin, which is the only prognostic factor under the control of the surgeon. A complete caudate lobectomy and resection of the inferior part of Couinaud’s segment IV coupled with right or left hemihepatectomy has become the standard surgical procedure for hilar cholangiocarcinoma, and pylorus-preserving pancreaticoduodenectomy is the first choice for distal bile duct cancer. Limited resection for middle bile duct cancer is indicated for only strictly selected cases. Preoperative treatments including biliary drainage and portal vein embolization are also indicated for only selected patients, especially jaundiced patients anticipating major hepatectomy. Liver transplantation seems ideal for complete resection of bile duct cancer, but the high recurrence rate and decreased patient survival after liver transplant preclude it from being considered standard treatment. Adjuvant chemotherapy and radiotherapy have a potentially crucial role in prolonging survival and controlling local recurrence, but no definite regimen has been established to date. Further evidence is needed to fully define the role of liver transplantation and adjuvant

  6. First Contact to Odors: Our Current Knowledge about Odorant Receptor

    Directory of Open Access Journals (Sweden)

    Cheil Moon

    2008-10-01

    Full Text Available Chemical senses – especially smell – are known to be important for the fundamental life events such as sensing predators, selecting mates, as well as finding food. The chemical senses are decoded in the olfactory system which is able to detect and differentiate thousands of odorous substances comprised of chemically divergent structures (i.e. odorants. The high selectivity of the olfactory system is heavily dependent on the receptors for each odorants (i.e. odorant receptors. Thus, studying odorant receptors may not only facilitate our understanding the initial events of olfaction but provide crucial knowledge for developing a novel, odorant receptor-based biosensor for chemical screening. Here we provide a review of recent advances in our understanding of odorant receptors.

  7. Current-limiting and recovery characteristics of a flux-lock-type SFCL with two adjustable operational currents

    Science.gov (United States)

    Ko, Seok-Cheol; Han, Tae-Hee; Lim, Sung-Hun

    2014-07-01

    In this research, the current-limiting and recovery characteristics of a flux-lock-type superconducting fault current limiter (SFCL) with two adjustable operational currents were analyzed. The flux-lock-type SFCL with two adjustable operational currents, which consists of two magneticallycoupled coils, two high-TC superconducting (HTSC) modules connected in parallel, and an inserting resistance connected in series with one of the two HTSC modules, can limit the fault current with two operational currents by quench generation in either one HTSC module for a lower fault current or two HTSC modules for a higher fault current directly after the fault occurrence. To verify the current-limiting operation of this type SFCL, we constructed the simulated power distribution system protected by the SFCL, and we executed the short-circuit tests in the fault locations with both the lower and the higher fault currents. Through an analysis of the experimental results, effective current limiting operations of the flux-lock-type SFCL could be confirmed.

  8. Arrhythmogenic KCNE gene variants: current knowledge and future challenges

    Directory of Open Access Journals (Sweden)

    Shawn M Crump

    2014-01-01

    Full Text Available There are twenty-five known inherited cardiac arrhythmia susceptibility genes, all of which encode either ion channel pore-forming subunits or proteins that regulate aspects of ion channel biology such as function, trafficking and localization. The human KCNE gene family comprises five potassium channel regulatory subunits, sequence variants in each of which are associated with cardiac arrhythmias. KCNE gene products exhibit promiscuous partnering and in some cases ubiquitous expression, hampering efforts to unequivocally correlate each gene to specific native potassium currents. Likewise, deducing the molecular etiology of cardiac arrhythmias in individuals harboring rare KCNE gene variants, or more common KCNE polymorphisms, can be challenging. In this review we provide an update on putative arrhythmia-causing KCNE gene variants, and discuss current thinking and future challenges in the study of molecular mechanisms of KCNE-associated cardiac rhythm disturbances.

  9. Drug evaluation studies in neonates: how to overcome the current limitations.

    Science.gov (United States)

    Allegaert, Karel; Smits, Anne; van den Anker, John

    2018-02-08

    Introduction Regulatory initiatives have stimulated drug research in infants, but the potential impact of drugs to improve health outcome in neonates remains underexplored. Areas covered In this review, we focus on current limitations in drug evaluation studies and how to overcome these. The low volume of studies has additional weaknesses such as single center studies, non-commercial sponsorship, overrepresentation of high postulated risk reductions, and underrepresentation of therapeutic exploratory studies. Master protocols and selection criteria for neonatal centers to participate in studies are useful to improve logistics related to performance. Limitations also relate to inaccurate assessment of drug effects (efficacy/safety). This is because of poor symptom recognition, case definitions, and suboptimal data on adverse drug reactions (ADRs) epidemiology. To overcome these limitations, it is necessary to develop core outcome sets, reference values, and specific ADR tools. The limitations identified and approaches suggested to improve drug evaluation are illustrated using neonatal abstinence syndrome as an example. Expert Commentary We anticipate to see an evolving neonatal clinical pharmacology discipline driven by neonatal pathophysiology and knowledge. Multidisciplinary collaborative efforts between health care providers, academia, pharmaceutical industry, advocacy groups and regulatory agencies are crucial to improve the impact of drug evaluation studies in neonates.

  10. Pharmacotherapy for Neonatal Seizures: Current Knowledge and Future Perspectives.

    Science.gov (United States)

    Donovan, Maria D; Griffin, Brendan T; Kharoshankaya, Liudmila; Cryan, John F; Boylan, Geraldine B

    2016-04-01

    Seizures are the most common neurological emergencies in the neonatal period and are associated with poor neurodevelopmental outcomes. Seizures affect up to five per 1000 term births and population-based studies suggest that they occur even more frequently in premature infants. Seizures are a sign of an underlying cerebral pathology, the most common of which is hypoxic-ischaemic encephalopathy in term infants. Due to a growing body of evidence that seizures exacerbate cerebral injury, effective diagnosis and treatment of neonatal seizures is of paramount importance to reduce long-term adverse outcomes. Electroencephalography is essential for the diagnosis of seizures in neonates due to their subtle clinical expression, non-specific neurological presentation and a high frequency of electro-clinical uncoupling in the neonatal period. Hypoxic-ischaemic encephalopathy may require neuroprotective therapeutic hypothermia, accompanying sedation with opioids, anticonvulsant drugs or a combination of all of these. The efficacy, safety, tolerability and pharmacokinetics of seven anticonvulsant drugs (phenobarbital, phenytoin, levetiracetam, lidocaine, midazolam, topiramate and bumetanide) are reviewed. This review is focused only on studies reporting electrographically confirmed seizures and highlights the knowledge gaps that exist in optimal treatment regimens for neonatal seizures. Randomised controlled trials are needed to establish a safe and effective treatment protocol for neonatal seizures.

  11. Current knowledge on biodegradable microspheres in drug delivery.

    Science.gov (United States)

    Prajapati, Vipul D; Jani, Girish K; Kapadia, Jinita R

    2015-08-01

    Biodegradable microspheres have gained popularity for delivering a wide variety of molecules via various routes. These types of products have been prepared using various natural and synthetic biodegradable polymers through suitable techniques for desired delivery of various challenging molecules. Selection of biodegradable polymers and technique play a key role in desired drug delivery. This review describes an overview of the fundamental knowledge and status of biodegradable microspheres in effective delivery of various molecules via desired routes with consideration of outlines of various compendial and non-compendial biodegradable polymers, formulation techniques and release mechanism of microspheres, patents and commercial biodegradable microspheres. There are various advantages of using biodegradable polymers including promise of development with different types of molecules. Biocompatibility, low dosage and reduced side effects are some reasons why usage biodegradable microspheres have gained in popularity. Selection of biodegradable polymers and formulation techniques to create microspheres is the biggest challenge in research. In the near future, biodegradable microspheres will become the eco-friendly product for drug delivery of various genes, hormones, proteins and peptides at specific site of body for desired periods of time.

  12. Vitamin K metabolism: current knowledge and future research.

    Science.gov (United States)

    Card, David J; Gorska, Renata; Cutler, Jacky; Harrington, Dominic J

    2014-08-01

    Vitamin K is an essential fat-soluble micronutrient that is required for the post-translational γ-carboxylation of specific glutamic acid residues in hepatic and extra-hepatic proteins involved in blood coagulation and preventing cartilage and vasculature calcification. In humans, sources of vitamin K are derived from plants as phylloquinone and bacteria as the menaquinones. Menadione is a synthetic product used as a pharmaceutical but also represents an intermediate in the tissue-specific conversion of vitamin K to menaquinone-4, which preferentially resides in tissues such as brain. Research into vitamin K metabolism is essential for the understanding of vitamin K biology in health and disease. Progress in this area, driven by knowledge of vitamin K and the availability of markers of vitamin K status, has already proved beneficial in many areas of medicine and further opportunities present themselves. Areas of interest discussed in this review include prophylactic administration of vitamin K1 in term and preterm neonates, interactions between vitamins K and E, the industrial conversion of vitamin K to dihydro-vitamin K in foods, tissue-specific conversion of vitamin K to menaquinone-4, the biological activity of the five and seven carbon metabolites of vitamin K and circadian variations. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Consumer health plan choice: current knowledge and future directions.

    Science.gov (United States)

    Scanlon, D P; Chernew, M; Lave, J R

    1997-01-01

    A keystone of the competitive strategy in health insurance markets is the assumption that "consumers" can make informed choices based on the costs and quality of competing health plans, and that selection effects are not large. However, little is known about how individuals use information other than price in the decision making process. This review summarizes the state of knowledge about how individuals make choices among health plans and outlines an agenda for future research. We find that the existing literature on health plan choice is no longer sufficient given the widespread growth and acceptance of managed care, and the increased proportion of consumers' income now going toward the purchase of health plans. Instead, today's environment of health plan choice requires better understanding of how plan attributes other than price influence plan choice, how other variables such as health status interact with plan attributes in the decision making process, and how specific populations differ from one another in terms of the sensitivity of their health plan choices to these different types of variables.

  14. Current state of knowledge about nutritional care of pregnant women

    Directory of Open Access Journals (Sweden)

    Luciana Barretto

    2014-12-01

    Full Text Available Pregnancy involves a significant anabolic activity that leads to increased nutritional needs relative to the preconception period. This paper aims to review the current understanding of the energy needs of macro and micronutrients during pregnancy as well as guidelines to address common gastrointestinal disorders during pregnancy, the issue of pica and anthropometric assessment to ensure an optimum weight gain. With the exception of iron, most of the nutrients needed by the pregnancy can be provided by a complete and balanced diet. Currently the scientific evidence shows that routine supplementation with iron and folic acid during pregnancy is a practice that prevents iron deficiency anemia, neural tube disorders and preterm births. Intermittent iron supplementation can also be an appropriated intervention. If the diet does not guarantee and adequate support, iodine, vitamin B12 and vitamin D supplements should also be necessaries. The anthropometric assessment by the pattern of weight gain should be present at each prenatal care visit to prevent maternal and fetal complications. In situations where the mother’s weight cannot be assessed, arm muscle circumference is possible to make an overall assessment as it correlates with maternal weight gain alternative. Measurements of biceps, triceps and subscapular skinfolds are another alternative that is useful to evaluate the fatty deposits and their location, in a complementary way to gain weight.

  15. Constructing Knowledge about the Notion of Limit in the Definition of the Horizontal Asymptote

    Science.gov (United States)

    Kidron, Ivy

    2011-01-01

    Processes of knowledge construction are investigated. A learner is constructing knowledge about the notion of limit in the definition of the horizontal asymptote. The analysis is based on the dynamically nested epistemic action model for abstraction in context. Different tasks are offered to the learner. In her effort to perform the different…

  16. Cyberbullying Prevention and Intervention Efforts: Current Knowledge and Future Directions.

    Science.gov (United States)

    Espelage, Dorothy L; Hong, Jun Sung

    2017-06-01

    Bullying is a serious public health concern that is associated with significant negative mental, social, and physical outcomes. Technological advances have increased adolescents' use of social media, and online communication platforms have exposed adolescents to another mode of bullying- cyberbullying. Prevention and intervention materials, from websites and tip sheets to classroom curriculum, have been developed to help youth, parents, and teachers address cyberbullying. While youth and parents are willing to disclose their experiences with bullying to their health care providers, these disclosures need to be taken seriously and handled in a caring manner. Health care providers need to include questions about bullying on intake forms to encourage these disclosures. The aim of this article is to examine the current status of cyberbullying prevention and intervention. Research support for several school-based intervention programs is summarised. Recommendations for future research are provided.

  17. Cyberbullying Prevention and Intervention Efforts: Current Knowledge and Future Directions

    Science.gov (United States)

    Hong, Jun Sung

    2016-01-01

    Bullying is a serious public health concern that is associated with significant negative mental, social, and physical outcomes. Technological advances have increased adolescents’ use of social media, and online communication platforms have exposed adolescents to another mode of bullying—cyberbullying. Prevention and intervention materials, from websites and tip sheets to classroom curriculum, have been developed to help youth, parents, and teachers address cyberbullying. While youth and parents are willing to disclose their experiences with bullying to their health care providers, these disclosures need to be taken seriously and handled in a caring manner. Health care providers need to include questions about bullying on intake forms to encourage these disclosures. The aim of this article is to examine the current status of cyberbullying prevention and intervention. Research support for several school-based intervention programs is summarised. Recommendations for future research are provided. PMID:28562094

  18. Current knowledge on the laboratory diagnosis of Clostridium difficile infection

    Science.gov (United States)

    Martínez-Meléndez, Adrián; Camacho-Ortiz, Adrián; Morfin-Otero, Rayo; Maldonado-Garza, Héctor Jesús; Villarreal-Treviño, Licet; Garza-González, Elvira

    2017-01-01

    Clostridium difficile (C. difficile) is a spore-forming, toxin-producing, gram-positive anaerobic bacterium that is the principal etiologic agent of antibiotic-associated diarrhea. Infection with C. difficile (CDI) is characterized by diarrhea in clinical syndromes that vary from self-limited to mild or severe. Since its initial recognition as the causative agent of pseudomembranous colitis, C. difficile has spread around the world. CDI is one of the most common healthcare-associated infections and a significant cause of morbidity and mortality among older adult hospitalized patients. Due to extensive antibiotic usage, the number of CDIs has increased. Diagnosis of CDI is often difficult and has a substantial impact on the management of patients with the disease, mainly with regards to antibiotic management. The diagnosis of CDI is primarily based on the clinical signs and symptoms and is only confirmed by laboratory testing. Despite the high burden of CDI and the increasing interest in the disease, episodes of CDI are often misdiagnosed. The reasons for misdiagnosis are the lack of clinical suspicion or the use of inappropriate tests. The proper diagnosis of CDI reduces transmission, prevents inadequate or unnecessary treatments, and assures best antibiotic treatment. We review the options for the laboratory diagnosis of CDI within the settings of the most accepted guidelines for CDI diagnosis, treatment, and prevention of CDI. PMID:28321156

  19. Current knowledge in the neurophysiologic modulation of obesity.

    Science.gov (United States)

    Angelopoulos, Nicholas; Goula, Anastasia; Tolis, George

    2005-09-01

    Obesity is today one of the commonest of life-threatening diseases in developed countries and generally results from an imbalance between energy intake and energy expenditure. Although there is increasing evidence for a genetic basis of obesity in some clinical syndromes, this seems to be the cause only in a limited number of patients and obesity is far from being considered as a gene-related disease. Eating is a complex and multifactorial process involving autonomous pathways that transfer sensory and motor information between the entire length of the digestive tract and the central nervous system. Modulation of the amount of energy that we take in as food involves several mechanisms and networks that connect the brain with the gut, this process being key to the regulation of body weight over time, as well as to the modification of long-term eating behaviors. Furthermore, this axis is closely coupled to other systems that are involved in energy homeostasis, namely, food preference, energy expenditure, and lifestyle. The identification of several neuropeptides that modulate eating behavior in various ways, along with studies performed in animal models, have focused attention on the role of these molecules and their clinical implications in the development of obesity in humans.

  20. Genetics of recurrent miscarriage: challenges, current knowledge, future directions.

    Directory of Open Access Journals (Sweden)

    Kristiina eRull

    2012-03-01

    Full Text Available Recurrent miscarriage (RM occurs in 1-3% of couples aiming at childbirth. Due to multifactorial etiology the clinical diagnosis of RM varies. The design of genetic/’omics’ studies to identify genes and biological mechanisms involved in pathogenesis of RM has challenges as there are several options in defining the study subjects (female patient and/or couple with miscarriages, fetus/placenta and controls. An ideal study would attempt a trio-design focusing on both partners as well as pregnancies of the couple. Application of genetic association studies focusing on pre-selected candidate genes with potential pathological effect in RM show limitations. Polymorphisms in ~100 genes have been investigated and association with RM is often inconclusive or negative. Also, implication of prognostic molecular diagnostic tests in clinical practice exhibits uncertainties. Future directions in investigating biomolecular risk factors for RM rely on integrating alternative approaches (SNPs, CNVs, gene/protein expression, epigenetic regulation in studies of single genes as well as whole-genome analysis. This would be enhanced by collaborative network between research centers and RM clinics.

  1. 46 CFR 11.713 - Requirements for maintaining current knowledge of waters to be navigated.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 1 2010-10-01 2010-10-01 false Requirements for maintaining current knowledge of waters... § 11.713 Requirements for maintaining current knowledge of waters to be navigated. (a) If a first class pilot has not served over a particular route within the past 60 months, that person's license or MMC...

  2. Pain in Neurodegenerative Disease: Current Knowledge and Future Perspectives

    Directory of Open Access Journals (Sweden)

    Marina de Tommaso

    2016-01-01

    Full Text Available Neurodegenerative diseases are going to increase as the life expectancy is getting longer. The management of neurodegenerative diseases such as Alzheimer’s disease (AD and other dementias, Parkinson’s disease (PD and PD related disorders, motor neuron diseases (MND, Huntington’s disease (HD, spinocerebellar ataxia (SCA, and spinal muscular atrophy (SMA, is mainly addressed to motor and cognitive impairment, with special care to vital functions as breathing and feeding. Many of these patients complain of painful symptoms though their origin is variable, and their presence is frequently not considered in the treatment guidelines, leaving their management to the decision of the clinicians alone. However, studies focusing on pain frequency in such disorders suggest a high prevalence of pain in selected populations from 38 to 75% in AD, 40% to 86% in PD, and 19 to 85% in MND. The methods of pain assessment vary between studies so the type of pain has been rarely reported. However, a prevalent nonneuropathic origin of pain emerged for MND and PD. In AD, no data on pain features are available. No controlled therapeutic trials and guidelines are currently available. Given the relevance of pain in neurodegenerative disorders, the comprehensive understanding of mechanisms and predisposing factors, the application and validation of specific scales, and new specific therapeutic trials are needed.

  3. The Limits to Transforming the Environment and the Limits to Sociological Knowledge

    Directory of Open Access Journals (Sweden)

    Ralph Schroeder

    2010-08-01

    Full Text Available This paper argues that the social sciences are fragmented in addressing the environmental challenge of increasing resource depletion. To address this problem, the paper puts forward a framework which encompasses several disciplinary approaches, and above all a long-term historical perspective and a realist sociology of science and technology which, in combination, provide a means of understanding the disruptive changes in the transformation of the environment. The paper then focuses on energy and gives an overview of the various social forces that can potentially counteract the future tensions arising from the foreseeable depletion of energy sources. It argues that only some of these countervailing forces—namely state intervention and technological innovation—provide viable potential solutions to these tensions. However, these solutions themselves face severe constraints. The paper concludes by arguing that a realistic assessment of constraints is the most useful, though limited, service that social science can contribute to our understanding of the relation between social and environmental transformation.

  4. The Benzodiazepine-Dementia Disorders Link: Current State of Knowledge.

    Science.gov (United States)

    Pariente, Antoine; de Gage, Sophie Billioti; Moore, Nicholas; Bégaud, Bernard

    2016-01-01

    The short-term effects of benzodiazepines on memory are well established and are suspected in the long term. Eleven studies have been published so far concerning benzodiazepine use and the risk of dementia disorders; nine of these studies concluded these drugs have a deleterious effect, one found a protective effect, and one (the most recently published) observed no effect. The positive association found in some studies could be due to a reverse causation bias since the main indications for benzodiazepines (e.g. sleep disorders, anxiety) can also be prodromes of dementia disorders. This bias is less likely for treatments started more than 10 years before the diagnosis. Among others, three mechanisms could underlie the potential influence of benzodiazepines on the development of dementia disorders. First, benzodiazepines can decrease beta-site amyloid precursor protein-cleaving enzyme 1 (BACE-1) and γ-secretase activity and slow down the accumulation of Aβ oligomers in the brain. This potential positive effect has never been confirmed; the same is true for the prevention of excitotoxicity through benzodiazepine anti-glutamatergic action. Second, since astrocytes located in the area of amyloid plaques could have gamma-aminobutyric acid (GABA)-secreting activity, patients with pre-dementia lesions could be at increased risk of presenting with more pronounced deleterious cognitive effects of benzodiazepines. Finally, owing to the neural compensation and cognitive reserve concepts, some subjects could cope with initial lesions by using/developing alternative networks. By lowering the brain activation level, benzodiazepines could limit this capacity. In conclusion, it is essential that animal studies explore the mechanistic hypotheses of this association found by most of the pharmacoepidemiological studies conducted on this topic.

  5. Sexual chemoecology of mosquitoes (Diptera, Culicidae): Current knowledge and implications for vector control programs.

    Science.gov (United States)

    Vaníčková, Lucie; Canale, Angelo; Benelli, Giovanni

    2017-04-01

    Mosquitoes (Diptera: Culicidae) act as vectors of medical and veterinary importance, due to their ability to transmit many pathogens and parasites. Renewed interest has been recently devoted to the potential of sterile insect technique (SIT) for mosquito suppression. However, the success of the SIT is mostly dependent on the ability of sterile males to compete for mates with the wild ones in the field. Nevertheless, little is known on the sexual chemical ecology of mosquitoes, with special reference to the role of chemical signals in males. We reviewed the current knowledge on mosquito sexual chemical ecology and other key cues affecting courtship and mating behavior. The information available on the aggregation and sex pheromones in mosquito males is rather limited. To the best of our knowledge, the components of the aggregation pheromone stimulating swarming mechanisms have been fully characterized only for Aedes aegypti, while evidence for aggregation pheromones in other mosquito species remains elusive. Further research on this issue is needed, as well as to dissect the relative importance of visual (with special reference to swarming landmarks), vibrational, olfactory and tactile cues perceived during swarming and mate. On the other hand, more knowledge is available for cuticular hydrocarbons, which modulate mating behavior in several species of economic importance. These compounds, coupled with volatile aggregation components, have potential interest for the development of monitoring and trapping systems. In addition, the analyses of cuticular hydrocarbons are essential for discrimination between closely related mosquito species and/or populations. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  6. Female genital cosmetic surgery: a critical review of current knowledge and contemporary debates.

    Science.gov (United States)

    Braun, Virginia

    2010-07-01

    Female genital cosmetic surgery procedures have gained popularity in the West in recent years. Marketing by surgeons promotes the surgeries, but professional organizations have started to question the promotion and practice of these procedures. Despite some surgeon claims of drastic transformations of psychological, emotional, and sexual life associated with the surgery, little reliable evidence of such effects exists. This article achieves two objectives. First, reviewing the published academic work on the topic, it identifies the current state of knowledge around female genital cosmetic procedures, as well as limitations in our knowledge. Second, examining a body of critical scholarship that raises sociological and psychological concerns not typically addressed in medical literature, it summarizes broader issues and debates. Overall, the article demonstrates a paucity of scientific knowledge and highlights a pressing need to consider the broader ramifications of surgical practices. "Today we have a whole society held in thrall to the drastic plastic of labial rejuvenation."( 1 ) "At the present time, the field of female cosmetic genital surgery is like the old Wild, Wild West: wide open and unregulated"( 2 ).

  7. Occult HCV Infection: The Current State of Knowledge

    Science.gov (United States)

    Rezaee-Zavareh, Mohammad Saeid; Hadi, Reza; Karimi-Sari, Hamidreza; Hossein Khosravi, Mohammad; Ajudani, Reza; Dolatimehr, Fardin; Ramezani-Binabaj, Mahdi; Miri, Seyyed Mohammad; Alavian, Seyed Moayed

    2015-01-01

    Context Occult HCV infection (OCI) is defined as the presence of HCV-RNA in hepatocytes and the absence of HCV in the serum according to usual tests. We aimed to define OCI and provide information about the currently available diagnostic methods. Then we focus on specific groups that are at high risk of OCI and finally investigate immune responses to OCI and the available treatment approaches. Evidence Acquisition PubMed, Scopus and Google Scholar were comprehensively searched with combination of following keywords: “occult”, “hepatitis C virus” and “occult HCV infection”. The definition of OCI, diagnostic methods, specific groups that are at high risk and available treatment approaches were extract from literature. An analysis of available articles on OCI also was done based on Scopus search results. Results OCI has been reported in several high-risk groups, especially in hemodialysis patients and subjects with cryptogenic liver disease. Furthermore, some studies have proposed a specific immune response for OCI in comparison with chronic hepatitis C (CHC). Conclusions With a clinical history of approximately 11 years, occult HCV infection can be considered an occult type of CHC. Evidences suggest that considering OCI in these high-risk groups seems to be necessary. We suggest that alternative diagnostic tests should be applied and that there is a need for the participation of all countries to determine the epidemiology of this type of HCV infection. Additionally, evaluating OCI in blood transfusion centers and in patients who receive large amounts of blood and clotting factors, such as patients with hemophilia, should be performed in future projects. PMID:26734487

  8. Oxytocin and Socioemotional Aging─Current Knowledge and Future Trends

    Directory of Open Access Journals (Sweden)

    Natalie C. Ebner

    2013-08-01

    Full Text Available The oxytocin (OT system is involved in various aspects of social cognition and prosocial behavior. Specifically, OT has been examined in the context of social memory, emotion recognition, cooperation, trust, empathy, and bonding, and─though evidence is somewhat mixed─intranasal OT appears to benefit aspects of socioemotional functioning. However, most of the extant data on aging and OT is from animal research and human OT research has focused largely on young adults. As such, though we know that various socioemotional capacities change with age, we know little about whether age-related changes in the OT system may underlie age-related differences in socioemotional functioning. In this review, we take a genetic-neuro-behavioral approach and evaluate current evidence on age-related changes in the OT system as well as the putative effects of these alterations on age-related socioemotional functioning. Looking forward, we identify informational gaps and propose an Age-Related Genetic, Neurobiological, Sociobehavioral Model of Oxytocin (AGeNeS-OT model which may structure and inform investigations into aging-related genetic, neural, and sociocognitive processes related to OT. As an exemplar of the use of the model, we report exploratory data suggesting differences in socioemotional processing associated with genetic variation in the oxytocin receptor gene (OXTR in samples of young and older adults. Information gained from this arena has translational potential in depression, social stress, and anxiety─all of which have high relevance in aging─and may contribute to reducing social isolation and improving well-being of individuals across the lifespan.

  9. Vitamin D in the light of current knowledge

    Directory of Open Access Journals (Sweden)

    Radlović Nedeljko

    2012-01-01

    Full Text Available Vitamin D, i.e. 1,25(OH 2D, is an essential factor, not only of homeostasis of calcium and phosphorus, but also of cell proliferation, differentiation and apoptosis, immune and hormonal regulation, as well as other body processes. Thus, its optimal presence in the body is of exceptional significance for health, both of children, as well as adults and elderly persons. Today, it is known that the lack of vitamin D, besides having negative effects on the skeleton and teeth, also contributes to the development of various malignancies, primarily of the large bowel, prostate and breasts, as well as of autoimmune and allergic diseases, diabetes mellitus type II, arterial hypertension and others. Considered from the biological aspect, physiological requirements in vitamin D are achieved by cutaneous synthesis from 7-dehydrocholesterol during sun exposure, while, except rarely, it is very scarce in food. Having in mind extensive evidence that sun exposure presents a high risk for the development of skin malignancies, primarily melanoma, it is clear that humans are deprived of the natural and basic source of vitamin D. In accordance, as well as based on numerous epidemiological studies showing the increase of diseases, in the basis of which vitamin D deficiency plays the important role, next led to the recommended dietary allowance of vitamin D, regardless of age. According to current attitudes, it is recommended that the daily dietary allowances of vitamin D. i.e. the quantity of oral intake that would safely cover the optimal body requirements should be 400 IU for ages 0-18 years, 600 IU for ages 19-70 years and 800 IU for persons aged over 70 years.

  10. Vitamin D in the light of current knowledge.

    Science.gov (United States)

    Radlović, Nedeljko; Mladenović, Marija; Simić, Dusica; Radlović, Petar

    2012-01-01

    Vitamin D, i.e., 1.25(OH)2D, is an essential factor, not only of homeostasis of calcium and phosphorus, but also of cell proliferation, differentiation and apoptosis, immune and hormonal regulation, as well as other body processes.Thus, its optimal presence in the body is of exceptional significance for health, both of children, as well as adults and elderly persons. Today, it is known that the lack of vitamin D, besides having negative effects on the skeleton and teeth, also contributes to the development of various malignancies, primarily of the large bowel, prostate and breasts, as well as of autoimmune and allergic diseases, diabetes mellitus type II, arterial hypertension and others. Considered from the biological aspect, physiological requirements in vitamin D are achieved by cutaneous synthesis from 7-dehydrocholesterol during sun exposure, while, except rarely, it is very scarce in food. Having in mind extensive evidence that sun exposure presents a high risk for the development of skin malignancies, primarily melanoma, it is clear that humans are deprived of the natural and basic source of vitamin D. In accordance, as well as based on numerous epidemiological studies showing the increase of diseases, in the basis of which vitamin D deficiency plays the important role, next led to the recommended dietary allowance of vitamin D, regardless of age. According to current attitudes, it is recommended that the daily dietary allowances of vitamin D, i.e., the quantity of oral intake that would safely cover the optimal body requirements should be 400 IU for ages 0-18 years, 600 IU for ages 19-70 years and 800 IU for persons aged over 70 years.

  11. Myeloid-Derived Suppressor Cells in the Tumor Microenvironment: Current Knowledge and Future Perspectives.

    Science.gov (United States)

    Ibáñez-Vea, Maria; Zuazo, Miren; Gato, Maria; Arasanz, Hugo; Fernández-Hinojal, Gonzalo; Escors, David; Kochan, Grazyna

    2017-10-14

    The current knowledge on tumor-infiltrating myeloid-derived suppressor cells (MDSCs) is based mainly on the extensive work performed in murine models. Data obtained for human counterparts are generated on the basis of tumor analysis from patient samples. Both sources of information led to determination of the main suppressive mechanisms used by these cell subsets in tumor-bearing hosts. As a result of the identification of protein targets responsible for MDSCs suppressive activity, different therapeutics agents have been used to eliminate/reduce their adverse effect. In the present work, we review the current knowledge on suppressive mechanisms of MDSCs and therapeutic treatments that interfere with their differentiation, expansion or activity. Based on the accumulation of new evidences supporting their importance for tumor progression and metastasis, the interest in these cell types is increasing. We revise the methods of MDSC generation/differentiation ex vivo that may help in overcoming problems associated with limited numbers of cells available from animals and patients for their study.

  12. The recursive universe cosmic complexity and the limits of scientific knowledge

    CERN Document Server

    Poundstone, WIlliam

    2013-01-01

    This fascinating popular science journey explores key concepts in information theory in terms of Conway's ""Game of Life"" program. The author explains the application of natural law to a random system and demonstrates the necessity of limits. Other topics include the limits of knowledge, paradox of complexity, Maxwell's demon, Big Bang theory, and much more. 1985 edition.

  13. Evaluation of Ferrite Chip Beads as Surge Current Limiters in Circuits with Tantalum Capacitors

    Science.gov (United States)

    Teverovsky, Alexander

    2014-01-01

    Limiting resistors are currently required to be connected in series with tantalum capacitors to reduce the risk of surge current failures. However, application of limiting resistors decreases substantially the efficiency of the power supply systems. An ideal surge current limiting device should have a negligible resistance for DC currents and high resistance at frequencies corresponding to transients in tantalum capacitors. This work evaluates the possibility of using chip ferrite beads (FB) as such devices. Twelve types of small size FBs from three manufacturers were used to evaluate their robustness under soldering stresses and at high surge current spikes associated with transients in tantalum capacitors. Results show that FBs are capable to withstand current pulses that are substantially greater than the specified current limits. However, due to a sharp decrease of impedance with current, FBs do not reduce surge currents to the required level that can be achieved with regular resistors.

  14. Evaluation of Current Knowledge, Awareness and Practice of Spirometry among Hospital -based Nigerian Doctors

    Science.gov (United States)

    2009-01-01

    Background Spirometry is a cost-effective diagnostic tool for evaluation of lung function and for case-finding in a resource-limited setting. The acceptance of this test depends on the awareness of its indications and the ability to interpret the results. No studies have assessed the knowledge of spirometry among Nigerian doctors. The aim of this study was to evaluate the current knowledge, awareness and practice of spirometry among hospital-based Nigerian doctors. Methods We carried out a cross-sectional survey among 321 doctors working in Nigerian hospitals between March 2008 and June 2008. Information on knowledge, awareness, practice of and barriers to spirometry were obtained using a pre-tested, self-administered structured questionnaire and the data were then analysed. Results Of the 321 doctors that participated, 108 (33.6%) reported that they have good knowledge of spirometry. One hundred and ninety-five (60.7%) were aware of the importance of spirometry in aiding the diagnosis of respiratory diseases; 213(66.4%) were aware of the importance of spirometry in determining the severity of diseases. Medical school was the most common source of knowledge on spirometry (64.5%). Eighty-one (25.2%) doctors reported having a spirometer in their hospitals. Doctors having access to a spirometer used it more frequently for aiding the diagnosis of COPD (40.7% vs.27.5%) and for monitoring of asthma (18.5% vs.11.3%) than those without access to a spirometer. The doctors working in University Teaching Hospitals and Federal Medical Centres (FMC) (22.4% vs. 4.5%) and those having access to a spirometer (40.7 vs.11.3%) were very confident of interpreting spirometry results compared to those working in District and General Hospitals and without access to a spirometer. Irrespective of access to a spirometer or the type of hospital they were employed in, doctors reported that unavailability of a spirometer was the greatest barrier to its use (62.5%) followed by lack of awareness

  15. 6. 6 kV/1. 5 kA-class superconducting fault current limiter development

    Energy Technology Data Exchange (ETDEWEB)

    Ito, D.; Yoneda, E.S.; Tsurunaga, K.; Tada, T. (Toshiba Corp., Kawasaki (Japan)); Hara, T.; Ohkuma, T.; Yamamoto, T. (Engineering Research Center, Tokyo Electric Power Co., Nishi-Tsutsujigaoka, Chofu, Tokyo 182 (JP))

    1992-01-01

    This paper reports that the authors have developed and tested a 6.6 kV/1.5 kA-class fault current limiter wound with a 42-strand AC superconducting wire having ultra-fine MbTi filaments in a high resistivity matrix. In experiments, voltages up to 7.2 kV were applied to the limiter with phase angles of 0, 45, and 90 degrees. The limiter was able to limit the fault current to 1.8 kA successfully from the 55 kA short-circuit current that would flow in a circuit without limiter.

  16. AC current loss of meander-shaped QMG current limiting device; Mianda jo QMG genryu soshi no koryu tsuden sonshitsu

    Energy Technology Data Exchange (ETDEWEB)

    Otabe, S.; Endo, T. [Kyushu Inst. of Tech, Fukuoka (Japan); Matsushita, T. [Kyushu Inst. of Tech, Fukuoka (Japan); Kyushu Univ., Fukuoka (Japan); Morita, M. [Nippon Steel Co., Ltd., Tokyo (Japan)

    2000-05-29

    It examines that it is applied to the resistive superconductivity current limiter, because Y-123 bulk superconductor produced by the QMG method has the high specific resistance. It examined energization characteristics of the QMG method Y-123 bulk superconductor current-limiting element made into the lengthen by choosing the meander shape until now, by the pulse method. The evaluation of the ac loss in energizing for practical use in respect of steady AC actually is important. In this study, using superconductive transformer which used the Bi-2223 silver sheath polycore line for the secondary roll line, it examined AC of the steady on alternating current call of the QMG current-limiting element of the meander shape in energizing. (NEDO)

  17. Leveraging Students' Intuitive Knowledge About the Formal Definition of a Limit

    OpenAIRE

    Adiredja, Aditya Prabhawa

    2014-01-01

    This dissertation explores the roles of students' intuitive knowledge in learning formal mathematics. The formal definition of a limit, or the epsilon-delta definition, is a critical topic in calculus for mathematics majors' development. It is typically the first occasion when students engage with rigorous, formal mathematics. Research has documented that the formal definition is a roadblock for most students in calculus, but has also de-emphasized the productive role of their prior knowledge...

  18. Crucial knowledge gaps in current understanding of climate change impacts on coral reef fishes

    KAUST Repository

    Wilson, S. K.

    2010-02-26

    Expert opinion was canvassed to identify crucial knowledge gaps in current understanding of climate change impacts on coral reef fishes. Scientists that had published three or more papers on the effects of climate and environmental factors on reef fishes were invited to submit five questions that, if addressed, would improve our understanding of climate change effects on coral reef fishes. Thirty-three scientists provided 155 questions, and 32 scientists scored these questions in terms of: (i) identifying a knowledge gap, (ii) achievability, (iii) applicability to a broad spectrum of species and reef habitats, and (iv) priority. Forty-two per cent of the questions related to habitat associations and community dynamics of fish, reflecting the established effects and immediate concern relating to climate-induced coral loss and habitat degradation. However, there were also questions on fish demographics, physiology, behaviour and management, all of which could be potentially affected by climate change. Irrespective of their individual expertise and background, scientists scored questions from different topics similarly, suggesting limited bias and recognition of a need for greater interdisciplinary and collaborative research. Presented here are the 53 highest-scoring unique questions. These questions should act as a guide for future research, providing a basis for better assessment and management of climate change impacts on coral reefs and associated fish communities.

  19. Crucial knowledge gaps in current understanding of climate change impacts on coral reef fishes.

    Science.gov (United States)

    Wilson, S K; Adjeroud, M; Bellwood, D R; Berumen, M L; Booth, D; Bozec, Y-Marie; Chabanet, P; Cheal, A; Cinner, J; Depczynski, M; Feary, D A; Gagliano, M; Graham, N A J; Halford, A R; Halpern, B S; Harborne, A R; Hoey, A S; Holbrook, S J; Jones, G P; Kulbiki, M; Letourneur, Y; De Loma, T L; McClanahan, T; McCormick, M I; Meekan, M G; Mumby, P J; Munday, P L; Ohman, M C; Pratchett, M S; Riegl, B; Sano, M; Schmitt, R J; Syms, C

    2010-03-15

    Expert opinion was canvassed to identify crucial knowledge gaps in current understanding of climate change impacts on coral reef fishes. Scientists that had published three or more papers on the effects of climate and environmental factors on reef fishes were invited to submit five questions that, if addressed, would improve our understanding of climate change effects on coral reef fishes. Thirty-three scientists provided 155 questions, and 32 scientists scored these questions in terms of: (i) identifying a knowledge gap, (ii) achievability, (iii) applicability to a broad spectrum of species and reef habitats, and (iv) priority. Forty-two per cent of the questions related to habitat associations and community dynamics of fish, reflecting the established effects and immediate concern relating to climate-induced coral loss and habitat degradation. However, there were also questions on fish demographics, physiology, behaviour and management, all of which could be potentially affected by climate change. Irrespective of their individual expertise and background, scientists scored questions from different topics similarly, suggesting limited bias and recognition of a need for greater interdisciplinary and collaborative research. Presented here are the 53 highest-scoring unique questions. These questions should act as a guide for future research, providing a basis for better assessment and management of climate change impacts on coral reefs and associated fish communities.

  20. Identification of the Competencies, Knowledge, and Skills Needed by School Nutrition Assistants in the Current Environment

    Science.gov (United States)

    Nettles, Mary Frances; Carr, Deborah H.; Cater, Jerry B.; Federico, Holly A.

    2009-01-01

    Purpose/Objectives: Study objectives were to identify the functional areas, competencies, knowledge, and skills needed by effective school nutrition (SN) assistants in the current SN environment, and determine at what point the SN assistant should be able to know/perform the knowledge/skill statement, at time of hire or after training. Methods: In…

  1. Nutrition Education Brings Behavior and Knowledge Change in Limited-Resource Older Adults

    Science.gov (United States)

    McClelland, Jacquelyn W.; Jayaratne, K.S.U.; Bird, Carolyn L.

    2013-01-01

    A prospective, controlled, randomized, crossover design was used to examine a nutrition education curriculum's effects on knowledge and behavior of 463 limited-resource older adults in 13 counties. Counties were randomized to begin with the treatment or control curriculum and then the remaining curriculum. Participants completed a pre-test…

  2. Psychology's Role in the Assessment of Erectile Dysfunction: Historical Precedents, Current Knowledge, and Methods.

    Science.gov (United States)

    Ackerman, Mark D.; Carey, Michael P.

    1995-01-01

    Describes the role of the psychologist in the evaluation of erectile dysfunction. Reviews current diagnostic criteria and provides a historical overview of the topic. Summarizes current epidemiologic knowledge, including data on prevalence and research on cognitive, affective, dydactic, and lifestyle etiologic risk factors. Discusses assessment…

  3. Sea urchin overgrazing of seagrasses: A review of current knowledge on causes, consequences, and management

    Science.gov (United States)

    Eklöf, J. S.; de la Torre-Castro, M.; Gullström, M.; Uku, J.; Muthiga, N.; Lyimo, T.; Bandeira, S. O.

    2008-09-01

    Sea urchins are one of the most common seagrass macro-grazers in contemporary seagrass systems. Occasionally their grazing rates exceed seagrass growth rates, a phenomenon sometimes referred to as overgrazing. Because of a reported increasing frequency of overgrazing events, concomitant with loss of seagrass-associated ecosystem services, it has been suggested that overgrazing is one of the key threats to tropical and subtropical seagrasses. In light of this, we review the current knowledge on causes, consequences, and management of sea urchin overgrazing of seagrasses. Initially we argue that the definition of overgrazing must include scale and impairment of ecosystem services, since this is the de facto definition used in the literature, and will highlight the potential societal costs of seagrass overgrazing. A review of 16 identified cases suggests that urchin overgrazing is a global phenomenon, ranging from temperate to tropical coastal waters and involving at least 11 seagrass and 7 urchin species. Even though most overgrazing events seem to affect areas of <0.5 km 2, and recovery often occurs within a few years, overgrazing can have a range of large, long-term indirect effects such as loss of associated fauna and decreased sediment stabilization. A range of drivers behind overgrazing have been suggested, including bottom-up (nutrient enrichment), top-down (reduced predation control due to e.g. overfishing), "side-in" mechanisms (e.g. changes in water temperature) and natural population fluctuations. Based on recent studies, there seems to be fairly strong support for the top-down and bottom-up hypotheses. However, many potential drivers often co-occur and interact, especially in areas with high anthropogenic pressure, suggesting that multiple disturbances—by simultaneously reducing predation control, increasing urchin recruitment and reducing the resistance of seagrasses—could pave the way for overgrazing. In management, the most common response to

  4. Current Limitations in the Control and Spread of Ticks that Affect Livestock: A Review

    Directory of Open Access Journals (Sweden)

    Agustín Estrada-Peña

    2013-04-01

    Full Text Available Ticks are well-known parasites that affect livestock productivity. This paper reviews the current knowledge regarding the spread of ticks with their impact in animal health and the limitations to achieve effective control measures. The forecasted trends in climate play an obvious role in promoting the spread of ticks in several regions. It appears that climate warming is pivotal in the spread and colonization of new territories by Rhipicephalus microplus in several regions of Africa. The reported increase in altitude of this tick species in the mountainous regions of Central and South America appears to be driven by such general trends in climate change. This factor, however, is not the only single contributor to the spread of ticks. The poor management of farms, uncontrolled movements of domestic animals, abundance of wild animals, and absence of an adequate framework to capture the ecological plasticity of certain ticks may explain the complexity of the control measures. In this paper, we review several details regarding the relationships of ticks with the environment, wild fauna and competition with other species of ticks. Our intention is to highlight these relationships with the aim to produce a coherent framework to explore tick ecology and its relationship with animal production systems.

  5. Global Assessment of Functioning (GAF: properties and frontier of current knowledge

    Directory of Open Access Journals (Sweden)

    Aas IH Monrad

    2010-05-01

    Full Text Available Abstract Background Global Assessment of Functioning (GAF is well known internationally and widely used for scoring the severity of illness in psychiatry. Problems with GAF show a need for its further development (for example validity and reliability problems. The aim of the present study was to identify gaps in current knowledge about properties of GAF that are of interest for further development. Properties of GAF are defined as characteristic traits or attributes that serve to define GAF (or may have a role to define a future updated GAF. Methods A thorough literature search was conducted. Results A number of gaps in knowledge about the properties of GAF were identified: for example, the current GAF has a continuous scale, but is a continuous or categorical scale better? Scoring is not performed by setting a mark directly on a visual scale, but could this improve scoring? Would new anchor points, including key words and examples, improve GAF (anchor points for symptoms, functioning, positive mental health, prognosis, improvement of generic properties, exclusion criteria for scoring in 10-point intervals, and anchor points at the endpoints of the scale? Is a change in the number of anchor points and their distribution over the total scale important? Could better instructions for scoring within 10-point intervals improve scoring? Internationally, both single and dual scales for GAF are used, but what is the advantage of having separate symptom and functioning scales? Symptom (GAF-S and functioning (GAF-F scales should score different dimensions and still be correlated, but what is the best combination of definitions for GAF-S and GAF-F? For GAF with more than two scales there is limited empirical testing, but what is gained or lost by using more than two scales? Conclusions In the history of GAF, its basic properties have undergone limited changes. Problems with GAF may, in part, be due to lack of a research programme testing the effects of

  6. The relationship between chiropractor required and current level of business knowledge.

    Science.gov (United States)

    Ciolfi, Michael Anthony; Kasen, Patsy Anne

    2017-01-01

    Chiropractors frequently practice within health care systems requiring the business acumen of an entrepreneur. However, some chiropractors do not know the relationship between the level of business knowledge required for practice success and their current level of business knowledge. The purpose of this quantitative study was to examine the relationship between chiropractors' perceived level of business knowledge required and their perceived level of current business knowledge. Two hundred and seventy-four participants completed an online survey (Health Care Training and Education Needs Survey) which included eight key business items. Participants rated the level of perceived business knowledge required (Part I) and their current perceived level of knowledge (Part II) for the same eight items. Data was collected from November 27, 2013 to December 18, 2013. Data were analyzed using Spearman's ranked correlation to determine the statistically significant relationships for the perceived level of knowledge required and the perceived current level of knowledge for each of the paired eight items from Parts I and II of the survey. Wilcoxon Signed Ranks Tests were performed to determine the statistical difference between the paired items. The results of Spearman's correlation testing indicated a statistically significant (p ethical, (e) managerial decisions, and (f) operations. Wilcoxon Signed Ranks testing indicated a significant difference for three paired items: strategic management; marketing and; legal and ethical. The results suggest that relationships exist for the majority of business items (6 of 8) however a statistically difference was demonstrated in only three of the paired business items. The implications of this study for social change include the potential to improve chiropractors' business knowledge and skills, enable practice success, enhance health services delivery and positively influence the profession as a viable career.

  7. Structure and Performance Characteristics of Saturated Iron-core Superconducting Fault Current Limiter

    National Research Council Canada - National Science Library

    Niu, Xiaoye; Chen, Zhili; Wang, Haizhen; Chen, Zhifu; Zhang, Lifeng; Niu, Guojun; Hong, Hui; Xin, Ying

    2014-01-01

    .... The immediately reacting and fast recovering are also its main characteristics. The structure and function of SISFCL is similar to that of traditional transformer and current limiting reactor respectively...

  8. Estimating Heat and Mass Transfer Processes in Green Roof Systems: Current Modeling Capabilities and Limitations (Presentation)

    Energy Technology Data Exchange (ETDEWEB)

    Tabares Velasco, P. C.

    2011-04-01

    This presentation discusses estimating heat and mass transfer processes in green roof systems: current modeling capabilities and limitations. Green roofs are 'specialized roofing systems that support vegetation growth on rooftops.'

  9. Current limiting characteristics of transformer type SFCL with coupled secondary windings according to its winding direction

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Sung Hun [Dept. of Electrical Engineering, Soongsil University, Seoul (Korea, Republic of); Han, Tae Hee [Dept. of Aero Materials Engineering, Jungwon University, Goesan (Korea, Republic of)

    2017-06-15

    In this paper, the current limiting characteristics of the transformer type superconducting fault current limiter (SFCL) with the two coupled secondary windings due to its winding direction were analyzed. To analyze the dependence of transient fault current limiting characteristics on the winding direction of the additional secondary winding, the fault current limiting tests of the SFCL with an additional secondary winding, wound as subtractive polarity winding and additive polarity winding, were carried out. The time interval of quench occurrence between two superconducting elements comprising the transformer type SFCL with the additional secondary winding was confirmed to be affected by the winding direction of the additional secondary winding. In case of the subtractive polarity winding of the additional secondary winding, the time interval of the quench occurrence in two superconducting elements was shorter than the case of the additive polarity winding.

  10. A web-based educational video to improve asthma knowledge for limited English proficiency Latino caregivers.

    Science.gov (United States)

    Riera, Antonio; Ocasio, Agueda; Tiyyagura, Gunjan; Thomas, Anita; Goncalves, Patricia; Krumeich, Lauren; Ragins, Kyle; Trevino, Sandra; Vaca, Federico E

    2017-08-01

    To evaluate limited English proficiency (LEP) Latino caregiver asthma knowledge after exposure to an educational video designed for this target group. A cross-sectional, interventional study was performed. We aimed to evaluate the post-test impact on asthma knowledge from baseline after exposure to a patient-centered, evidence-based, and professionally produced Spanish asthma educational video. Participants included LEP Latino caregivers of children 2-12 years old with persistent asthma. Enrollment was performed during ED encounters or scheduled through a local community organization. Asthma knowledge was measured with a validated Spanish parental asthma knowledge questionnaire. Differences in mean scores were calculated with a paired t-test. Twenty caregivers were enrolled. Participants included mothers (100%) from Puerto Rico (75%), with a high-school diploma or higher (85%), with no written asthma action plan (65%), whose child's asthma diagnosis was present for at least 3 years (80%). Mean baseline asthma knowledge scores improved 8 points from 58.4 to 66.4 after watching the educational video (95% CI 5.3-10.7; t(19) = 6.21, p asthma knowledge for a Latino population facing communication barriers to quality asthma care. Dissemination of this educational resource to LEP caregivers has the potential to improve pediatric asthma care in the United States.

  11. Current knowledge and perception of bariatric surgery among Greek doctors living in Thessaly.

    Science.gov (United States)

    Zacharoulis, Dimitris; Bakalis, Vissarion; Zachari, Eleni; Sioka, Eleni; Tsimpida, Dialecthi; Magouliotis, Dimitrios; Tasiopoulou, Vasiliki; Chatedaki, Christina; Tzovaras, George

    2017-11-03

    The purpose of this study was to assess doctors' knowledge, current conceptions, and clinical practice regarding obesity and bariatric surgery. A self-administered survey was administered to 500 doctors with varying medical specialties in public and private practice. The response rate was 60%. Most participants (77.3%) were in private practice. Although almost half of the participants could define morbid obesity and obesity-related comorbidities, only 8.7% felt educated about bariatric surgery. Participants had little knowledge of various types of bariatric procedures. A minority of doctors (24.7%) knew of the existence of a bariatric center in their area. Only 21.3% of doctors had referred a patient to a bariatric center. Reasons for non-referral included lack of interest in bariatric surgery (37.3%), patient refusal (35.3%), increased operative fees (17.3%), lack of confidence in bariatric surgery (6.3%), and lack of access to a nearby bariatric center (3.7%). The majority of doctors were interested in learning more about bariatric surgery and related guidelines, but they remained reluctant to conduct patients' postoperative follow-ups. The penetration of bariatric surgery in the medical community remains limited, despite its proven effectiveness in facilitating sustained weight loss and resolving several obesity-related comorbidities. A great effort should be made to inform health-care providers about the evolution of bariatric procedures, the potential benefits they offer, and the existence of certified bariatric centers. This will allow doctors to provide optimum health care to patients who could benefit from bariatric surgery. © 2017 Japan Society for Endoscopic Surgery, Asia Endosurgery Task Force and John Wiley & Sons Australia, Ltd.

  12. Current Knowledge in lentil genomics and its application for crop improvement

    Directory of Open Access Journals (Sweden)

    Shiv eKumar

    2015-02-01

    Full Text Available Most of the lentil growing countries face a certain set of abiotic and biotic stresses causing substantial reduction in crop growth, yield, and production. Until-to date, lentil breeders have used conventional plant breeding techniques of selection-recombination-selection cycle to develop improved cultivars. These techniques have been successful in mainstreaming some of the easy-to-manage monogenic traits. However in case of complex quantitative traits, these conventional techniques are less precise. As most of the economic traits are complex, quantitative and often influenced by environments and genotype-environment (GE interaction, the genetic improvement of these traits becomes difficult. Genomics assisted breeding is relatively powerful and fast approach to develop high yielding varieties more suitable to adverse environmental conditions. New tools such as molecular markers and bioinformatics are expected to generate new knowledge and improve our understanding on the genetics of complex traits. In the past, the limited availability of genomic resources in lentil could not allow breeders to employ these tools in mainstream breeding program. The recent application of the Next Generation Sequencing (NGS and Genotyping by sequencing (GBS technologies has facilitated to speed up the lentil genome sequencing project and large discovery of genome-wide SNP markers. Recently, several linkage maps have been developed in lentil through the use of Expressed Sequenced Tag (EST-derived Simple Sequence Repeat (SSR and Single Nucleotide Polymorphism (SNP markers. These maps have emerged as useful genomic resources to identify QTL imparting tolerance to biotic and abiotic stresses in lentil. In this review, the current knowledge on available genomic resources and its application in lentil breeding program are discussed.

  13. Tiger Beetles' (Coleoptera: Carabidae, Cicindelinae) pupal stage: current state of knowledge and future perspectives.

    Science.gov (United States)

    Roza, André S; Mermudes, José R M

    2017-01-26

    The tiger beetles (Carabidae: Cicindelinae) include about 2,822 species and 120 genera around the world. They are one of the most widely studied families of Coleoptera. However, the knowledge about their immature stages is incipient and usually restricted to the larval stages. Pupal characteristics have been among the most ignored aspects of tiger beetle biology. Here we compile and update the current knowledge of tiger beetle pupae.

  14. 3D Nonlinear transies field-circuit modeling of inductive fault current limiters

    NARCIS (Netherlands)

    Cvoric, D.; Lahaye, D.; De Haan, S.W.H.; Ferreira, J.A.

    2013-01-01

    Due to increasing levels of fault currents, Fault Current Limiters (FCLs) are expected to play an important role in the protection of future power grids. Inductive saturable FCLs are particularly interesting due to their inherent reaction on the fault. Many different configurations have been

  15. Vitamin C Transporters in Cancer: Current Understanding and Gaps in Knowledge

    Directory of Open Access Journals (Sweden)

    Gabi U. Dachs

    2017-04-01

    Full Text Available Sufficient uptake and whole body distribution of vitamin C (ascorbate is essential for many biochemical processes, including some that are vital for tumor growth and spread. Uptake of ascorbate into cancer cells is modulated by availability, tumor blood flow, tissue diffusion parameters, and ascorbate transport proteins. Uptake into cells is mediated by two families of transport proteins, namely, the solute carrier gene family 23, consisting of sodium-dependent vitamin C transporters (SVCTs 1 and 2, and the SLC2 family of glucose transporters (GLUTs. GLUTs transport the oxidized form of the vitamin, dehydroascorbate (DHA, which is present at negligible to low physiological levels. SVCT1 and 2 are capable of accumulating ascorbate against a concentration gradient from micromolar concentrations outside to millimolar levels inside of cells. Investigating the expression and regulation of SVCTs in cancer has only recently started to be included in studies focused on the role of ascorbate in tumor formation, progression, and response to therapy. This review gives an overview of the current, limited knowledge of ascorbate transport across membranes, as well as tissue distribution, gene expression, and the relevance of SVCTs in cancer. As tumor ascorbate accumulation may play a role in the anticancer activity of high dose ascorbate treatment, further research into ascorbate transport in cancer tissue is vital.

  16. Multi-soft gluon limits and extended current algebras at null-infinity

    Science.gov (United States)

    McLoughlin, Tristan; Nandan, Dhritiman

    2017-08-01

    In this note we consider aspects of the current algebra interpretation of multisoft limits of tree-level gluon scattering amplitudes in four dimensions. Building on the relation between a positive helicity gluon soft-limit and the Ward identity for a level-zero Kac-Moody current, we use the double-soft limit to define the Sugawara energy-momentum tensor and, by using the triple- and quadruple-soft limits, show that it satisfies the correct OPEs for a CFT. We study the resulting Knizhnik-Zamolodchikov equations and show that they hold for positive helicity gluons in MHV amplitudes. Turning to the sub-leading soft-terms we define a one-parameter family of currents whose Ward identities corresponding to the universal tree-level sub-leading soft-behaviour. We compute the algebra of these currents formed with the leading currents and amongst themselves. Finally, by parameterising the ambiguity in the double-soft limit for mixed helicities, we introduce a non-trivial OPE between the holomorphic and anti-holomorphic currents and study some of its implications.

  17. The island of knowledge the limits of science and the search for meaning

    CERN Document Server

    Gleiser, Marcelo

    2014-01-01

    Do all questions have answers? How much can we know about the world? Is there such a thing as an ultimate truth? To be human is to want to know, but what we are able to observe is only a tiny portion of what’s “out there.” In The Island of Knowledge, physicist Marcelo Gleiser traces our search for answers to the most fundamental questions of existence. In so doing, he reaches a provocative conclusion: science, the main tool we use to find answers, is fundamentally limited. These limits to our knowledge arise both from our tools of exploration and from the nature of physical reality: the speed of light, the uncertainty principle, the impossibility of seeing beyond the cosmic horizon, the incompleteness theorem, and our own limitations as an intelligent species. Recognizing limits in this way, Gleiser argues, is not a deterrent to progress or a surrendering to religion. Rather, it frees us to question the meaning and nature of the universe while affirming the central role of life and ourselves in it. Sc...

  18. First experimental results with the Current Limit Avoidance System at the JET tokamak

    Energy Technology Data Exchange (ETDEWEB)

    De Tommasi, G. [Associazione EURATOM-ENEA-CREATE, Università di Napoli Federico II, Via Claudio 21, 80125 Napoli (Italy); Galeani, S. [Dipartimento di Informatica, Sistemi e Produzione, Università di Roma, Tor Vergata, Rome (Italy); Jachmich, S. [Association EURATOM-Belgian State, Koninklijke Militaire School - Ecole Royale Militaire, B-1000 Brussels (Belgium); Joffrin, E. [IRFM-CEA, Centre de Cadarache, 13108 Saint-paul-lez-Durance (France); Lennholm, M. [EFDA Close Support Unit, Culham Science Centre, OX14 3DB Abingdon (United Kingdom); European Commission, B-1049 Brussels (Belgium); Lomas, P.J. [Euratom-CCFE, Culham Science Centre, OX14 3DB Abingdon (United Kingdom); Neto, A.C. [Associazione EURATOM-IST, Instituto de Plasmas e Fusao Nuclear, IST, 1049-001 Lisboa (Portugal); Maviglia, F. [Associazione EURATOM-ENEA-CREATE, Via Claudio 21, 80125 Napoli (Italy); McCullen, P. [Euratom-CCFE, Culham Science Centre, OX14 3DB Abingdon (United Kingdom); Pironti, A. [Associazione EURATOM-ENEA-CREATE, Università di Napoli Federico II, Via Claudio 21, 80125 Napoli (Italy); Rimini, F.G. [Euratom-CCFE, Culham Science Centre, OX14 3DB Abingdon (United Kingdom); Sips, A.C.C. [European Commission, B-1049 Brussels (Belgium); Varano, G.; Vitelli, R. [Dipartimento di Informatica, Sistemi e Produzione, Università di Roma, Tor Vergata, Rome (Italy); Zaccarian, L. [CNRS, LAAS, 7 Avenue du Colonel Roche, F-31400 Toulouse (France); Universitè de Toulouse, LAAS, F-31400 Toulouse (France)

    2013-06-15

    The Current Limit Avoidance System (CLA) has been recently deployed at the JET tokamak to avoid current saturations in the poloidal field (PF) coils when the eXtreme Shape Controller is used to control the plasma shape. In order to cope with the current saturation limits, the CLA exploits the redundancy of the PF coils system to automatically obtain almost the same plasma shape using a different combination of currents in the PF coils. In the presence of disturbances it tries to avoid the current saturations by relaxing the constraints on the plasma shape control. The CLA system has been successfully implemented on the JET tokamak and fully commissioned in 2011. This paper presents the first experimental results achieved in 2011–2012 during the restart and the ITER-like wall campaigns at JET.

  19. Taking stock of current societal, political and academic stakeholders in the Canadian healthcare knowledge translation agenda

    Directory of Open Access Journals (Sweden)

    Scott-Findlay Shannon

    2007-10-01

    Full Text Available Abstract Background In the past 15 years, knowledge translation in healthcare has emerged as a multifaceted and complex agenda. Theoretical and polemical discussions, the development of a science to study and measure the effects of translating research evidence into healthcare, and the role of key stakeholders including academe, healthcare decision-makers, the public, and government funding bodies have brought scholarly, organizational, social, and political dimensions to the agenda. Objective This paper discusses the current knowledge translation agenda in Canadian healthcare and how elements in this agenda shape the discovery and translation of health knowledge. Discussion The current knowledge translation agenda in Canadian healthcare involves the influence of values, priorities, and people; stakes which greatly shape the discovery of research knowledge and how it is or is not instituted in healthcare delivery. As this agenda continues to take shape and direction, ensuring that it is accountable for its influences is essential and should be at the forefront of concern to the Canadian public and healthcare community. This transparency will allow for scrutiny, debate, and improvements in health knowledge discovery and health services delivery.

  20. Current state of knowledge on aetiology, diagnosis, management, and therapy of myocarditis

    DEFF Research Database (Denmark)

    Caforio, Alida L P; Pankuweit, Sabine; Arbustini, Eloisa

    2013-01-01

    In this position statement of the ESC Working Group on Myocardial and Pericardial Diseases an expert consensus group reviews the current knowledge on clinical presentation, diagnosis and treatment of myocarditis, and proposes new diagnostic criteria for clinically suspected myocarditis and its di...

  1. Encouraging Civic Knowledge and Engagement: Exploring Current Events through a Psychological Lens

    Science.gov (United States)

    Van Camp, Debbie; Baugh, Stacey-Ann

    2016-01-01

    Engagement with political, social, and civil issues is a fundamental component of an educated population, but civic knowledge and engagement are decreasing among adolescents and young adults. A Psychology in Current Events class sought to increase this engagement and key skills such as critical thinking. A one-group pretest-posttest…

  2. Determining Science Teacher Candidates' Academic Knowledge and Misconceptions about Electric Current

    Science.gov (United States)

    Sert Çibik, Ayse

    2017-01-01

    The aim of this study is two-fold. Its first aim is to determine science teacher candidates' knowledge (academic success) and misconceptions about electric current and its second aim is to compare these results across participants' year of study and gender. A total of 132 teacher candidates studying in their 2nd, 3rd, and 4th years in Gazi…

  3. Rheumatologists' knowledge, attitude and current management of fatigue in patients with rheumatoid arthritis (RA).

    NARCIS (Netherlands)

    Repping-Wuts, H.; Riel, P.L.C.M. van; Achterberg, T. van

    2008-01-01

    To describe rheumatologists' knowledge, attitude and current management of fatigue in patients with rheumatoid arthritis (RA), a postal questionnaire was sent to all rheumatologists (N = 204) and trainees (N = 49), members of the Dutch Society of Rheumatology. The overall response rate was 44% (N =

  4. Analisa Penggunaan Superconducting Fault Current Limiter (SFCL Untuk Melindungi Peralatan di PT Pindo Deli

    Directory of Open Access Journals (Sweden)

    Yohanes Sabriant Widyo Utomo

    2015-12-01

    Full Text Available Increas demand load and power capacity requirement at PT Pindo Deli then the short circuit current that occur will be greater. this can cause damage to electrical equipment located around the point of interrupting and resulting failure of the electrical system in power distribution. from the analysis of the three phase short circuit current 1/2 cycle seen that the bus 1 exceeds the peak breacing  asimetry equipment.  Where breacing peak bus asymetri 1 was 43.88 kA. While the peak of 3-phase  short circuit on the bus 1 is 47.98 kA.  To protect the equipment and the entire electrical system in PT Pindo Deli would require  the use of Superconducting Fault Current Limiter (SFCL that will be placed on buses that  exceed or approach the critical point. There are two kinds of Superconducting Fault Current Limiter that type of resistive and saturated iron core. In this final project SFCL used  is a hybrid resistive Superconducting Fault Current Limiting. By using a hybrid resistive  SFCL then flow disturbance will quickly be reduced by utilizing the reactance of Current  Limiting Reactor (CLR that is connected parallel with superonductor So as to secure all the equipment and electrical systems of a total blackout. After determination of Superconducting Fault Current Limiter setting the overcurrent relay coordination to determine whether existing coordination setting in accordance with the conditions there.  The coordination displayed using the curve Current Time Curve (TCC.

  5. Current self-limitation in a transverse nanosecond discharge with a slotted cathode

    Science.gov (United States)

    Ashurbekov, N. A.; Iminov, K. O.; Popov, O. A.; Shakhsinov, G. S.

    2017-03-01

    A high-voltage transverse pulsed nanosecond discharge with a slotted hollow cathode was found to be a source of high-energy (few kV) ribbon electron beams. Conditions for the formation and extinction of electron beams were experimentally studied in discharges in helium at pressures of 1-100 Torr. It was found that interaction of fast electrons with a non-uniform electric field near the slotted cathode led to limitation of the magnitude of the discharge current. A physical model was developed to describe the discharge current self-limitation that was in satisfactory agreement with the experimental results. Some technical solutions that are expected to increase the upper current limits in transverse nanosecond discharge are discussed.

  6. Implementation of superconducting fault current limiter for flexible operation in the power substation

    Science.gov (United States)

    Song, Chong Suk; Lee, Hansang; Cho, Yoon-sung; Suh, Jaewan; Jang, Gilsoo

    2014-09-01

    The concentration of large-scale power loads located in the metropolitan areas have resulted in high fault current levels during a fault thereby requiring the substation to operate in the double busbar configuration mode. However, the double busbar configuration mode results in deterioration of power system reliability and unbalanced power flow in the adjacent transmission lines which may result in issues such as overloading of lines. This paper proposes the implementation of the superconducting fault current limiter (SFCL) to be installed between the two substation busbars for a more efficient and flexible operation of the substation enabling both single and double busbar configurations depending on the system conditions for guaranteeing power system reliability as well as fault current limitations. Case studies are being performed for the effectiveness of the SFCL installation and results are compared for the cases where the substation is operating in single and double busbar mode and with and without the installation of the SFCL for fault current mitigation.

  7. Regge limit of R-current correlators in AdS supergravity

    Energy Technology Data Exchange (ETDEWEB)

    Bartels, J.; Kotanski, J.; Mischler, A.M. [II. Inst. fuer Theoretische Physik, Univ. Hamburg (Germany); Schomerus, V. [Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)

    2009-08-15

    Four-point functions of R-currents are discussed within Anti-de Sitter supergravity. In particular, we compute Witten diagrams with graviton and gauge boson exchange in the high energy Regge limit. Assuming validity of the AdS/CFT correspondence, our results apply to R-current four-point functions of N=4 super Yang-Mills theory at strong coupling. (orig.)

  8. Surveillance of fetal arrhythmias in the outpatient setting: current limitations and call for action.

    Science.gov (United States)

    Freire, Grace

    2015-12-01

    Surveillance of fetal arrhythmias in the outpatient setting remains limited by lack of monitoring modalities. Despite technological advances made in the field of obstetrics, existing devices are not currently suitable to monitor fetal arrhythmias. In this report, the author describes the current and developing fetal heart rate monitoring technologies including the recent introduction of hand-held Doppler monitors for outpatient surveillance of fetal arrhythmias.

  9. Febrile Seizures and Febrile Seizure Syndromes: An Updated Overview of Old and Current Knowledge

    Science.gov (United States)

    Khair, Abdulhafeez M.; Elmagrabi, Dalal

    2015-01-01

    Febrile seizures are the most common paroxysmal episode during childhood, affecting up to one in 10 children. They are a major cause of emergency facility visits and a source of family distress and anxiety. Their etiology and pathophysiological pathways are being understood better over time; however, there is still more to learn. Genetic predisposition is thought to be a major contributor. Febrile seizures have been historically classified as benign; however, many emerging febrile seizure syndromes behave differently. The way in which human knowledge has evolved over the years in regard to febrile seizures has not been dealt with in depth in the current literature, up to our current knowledge. This review serves as a documentary of how scientists have explored febrile seizures, elaborating on the journey of knowledge as far as etiology, clinical features, approach, and treatment strategies are concerned. Although this review cannot cover all clinical aspects related to febrile seizures at the textbook level, we believe it can function as a quick summary of the past and current sources of knowledge for all varieties of febrile seizure types and syndromes. PMID:26697219

  10. Galictis cuja (Mammalia: an update of current knowledge and geographic distribution

    Directory of Open Access Journals (Sweden)

    Daniela A. Poo-Muñoz

    2014-09-01

    Full Text Available The lesser grison (Galictis cuja is one of the least-known mustelids in the Neotropics, despite its broad range across South America. This study aimed to explore current knowledge of the distribution of the species to identify gaps in knowledge and anticipate its full geographic distribution. Eighty-nine articles have mentioned G. cuja since 1969, but only 13 focused on the species. We generated a detailed model of the species' potential distribution that validated previous maps, but with improved detail, supporting previous southernmost records, and providing a means of identifying priority sites for conservation and management of the species.

  11. Epigenetic mechanisms in microbial members of the human microbiota: current knowledge and perspectives.

    Science.gov (United States)

    Cureau, Natacha; AlJahdali, Nesreen; Vo, Nguyen; Carbonero, Franck

    2016-09-01

    The human microbiota and epigenetic processes have both been shown to play a crucial role in health and disease. However, there is extremely scarce information on epigenetic modulation of microbiota members except for a few pathogens. Mainly DNA adenine methylation has been described extensively in modulating the virulence of pathogenic bacteria in particular. It would thus appear likely that such mechanisms are widespread for most bacterial members of the microbiota. This review will present briefly the current knowledge on epigenetic processes in bacteria, give examples of known methylation processes in microbial members of the human microbiota and summarize the knowledge on regulation of host epigenetic processes by the human microbiota.

  12. Single injection space-charge-limited current in insulator with two sets of distributed traps

    Science.gov (United States)

    Kumar, M.; Vashistha, G. K.; Sharma, Y. K.

    2007-11-01

    A study of single injection space-charge-limited current flow in insulator with two sets of traps distributed in energy is presented for a particular situation in which the energy separation of the two sets of traps is too small to give rise a current-voltage characteristic with maximum structure. The current-voltage characteristic is obtained in a simplified way with the help of regional approximation method. The obtained J-V characteristic is compared with previously reported experimental work on p-type GaSe sample. The comparison shows very good agreement between theoretical and experimental result, confirming the correctness of the analysis.

  13. Implementation of superconducting fault current limiter for flexible operation in the power substation

    Energy Technology Data Exchange (ETDEWEB)

    Song, Chong Suk, E-mail: chong_suk@korea.ac.kr [School of Electrical Engineering, Korea University, Anam dong, Seonbukgu, Seoul 136-713 (Korea, Republic of); Lee, Hansang [School of Railway and Electrical Engineering, Kyungil University, Hayang-eup, Gyeongsan-si, Gyeongsangbuk-do 712-701 (Korea, Republic of); Cho, Yoon-sung [Department of Electric and Energy Engineering, Catholic University of Daegu, Hayang-eup, Gyeongsan-si, Gyeongsangbuk-do 712-702 (Korea, Republic of); Suh, Jaewan [School of Electrical Engineering, Korea University, Anam dong, Seonbukgu, Seoul 136-713 (Korea, Republic of); Jang, Gilsoo, E-mail: gjang@korea.ac.kr [School of Electrical Engineering, Korea University, Anam dong, Seonbukgu, Seoul 136-713 (Korea, Republic of)

    2014-09-15

    Highlights: • The power load concentrated in load centers results in high levels of fault current. • This paper introduces a fault current reduction scheme using SFCLs in substations. • The SFCL is connected in parallel to the bus tie between the two busbars. • The fault current mitigation using SFCLs is verified through PSS/e simulations. - Abstract: The concentration of large-scale power loads located in the metropolitan areas have resulted in high fault current levels during a fault thereby requiring the substation to operate in the double busbar configuration mode. However, the double busbar configuration mode results in deterioration of power system reliability and unbalanced power flow in the adjacent transmission lines which may result in issues such as overloading of lines. This paper proposes the implementation of the superconducting fault current limiter (SFCL) to be installed between the two substation busbars for a more efficient and flexible operation of the substation enabling both single and double busbar configurations depending on the system conditions for guaranteeing power system reliability as well as fault current limitations. Case studies are being performed for the effectiveness of the SFCL installation and results are compared for the cases where the substation is operating in single and double busbar mode and with and without the installation of the SFCL for fault current mitigation.

  14. THE MATHEMATIC MODEL OF POTENTIAL RELAXATION IN COULOSTATIC CONDITIONS FOR LIMITING DIFFUSION CURRENT CASE

    Directory of Open Access Journals (Sweden)

    O. H. Kapitonov

    2010-05-01

    Full Text Available A mathematical model of coulostatic relaxation of the potential for solid metallic electrode was presented. The solution in the case of limiting diffusion current was obtained. On the basis of this model the technique of concentration measurements for heavy metal ions in diluted solutions was suggested. The model adequacy was proved by experimental data.

  15. Effect of limiter currents on plasma equilibrium and stability in a tokamak

    Science.gov (United States)

    Belashov, V. I.; Gribov, Yu. V.; Putvinskij, S. V.; Brevnov, N. N.

    The results of theoretical and experimental research of currents between diaphragms limiting plasma cord in tokamak on plasma equilibrium and stability with an arbitrary form of transverse cross section are presented. It is shown that plasma cord behaviour depends on applied voltage polarity. The phenomena considered can be important for tokamaks in which fast plasma compression in a big radius is invisaged.

  16. Removing the current-limit of vertical organic field effect transistors

    Science.gov (United States)

    Sheleg, Gil; Greenman, Michael; Lussem, Bjorn; Tessler, Nir

    2017-11-01

    The reported Vertical Organic Field Effect Transistors (VOFETs) show either superior current and switching speeds or well-behaved transistor performance, especially saturation in the output characteristics. Through the study of the relationship between the device architecture or dimensions and the device performance, we find that achieving a saturation regime in the output characteristics requires that the device operates in the injection limited regime. In current structures, the existence of the injection limited regime depends on the source's injection barrier as well as on the buried semiconductor layer thickness. To overcome the injection limit imposed by the necessity of injection barrier, we suggest a new architecture to realize VOFETs. This architecture shows better gate control and is independent of the injection barrier at the source, thus allowing for several A cm-2 for a semiconductor having a mobility value of 0.1 cm2 V-1 s-1.

  17. A strategy for protection of high voltage systems using resistive superconducting fault current limiters

    Science.gov (United States)

    Schettino, H. J.; Andrade, R. de, Jr.; Polasek, A.; Kottonau, D.; de Sousa, W. T. B.

    2018-01-01

    This work describes an use of a resistive superconducting fault current limiter (R-SFCL) device based on second generation high temperature superconductors tapes (2G tapes), using a thermal-electrical analogy method to represent heat exchanges. The considered SFCL is supposed to be inserted into the coupling point of a new generation unit to a 12 bar CIGRE benchmark transmission system. The strategy is the investigation of the limitation performance in the high voltage grid by connecting the SFCL at medium voltage grid. We evaluated the performance of the SFCL through the analysis of two cases of faults in different points of the system. Results show that a correct design of the SFCL may effectively limit the contribution of fault currents in the high voltage side. Additionally, it was possible to investigate the behavior of the device internal variables such as the temperature of the superconducting layers for the different cases studied.

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

    DEFF Research Database (Denmark)

    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...... current density can be accomplished either by gas-phase diffusion or liquid-phase diffusion, and it is the latter that can be used in the film-thickness estimation. It is also important to mention that at such a limiting condition, both the thin-film model and the filmed agglomerate model reach the same......Various models have been devoted to the operation mechanism of porous diffusion electrodes. They are, however, suffering from the lack of accuracy concerning the acid-film thickness on which they are based. In the present paper the limiting current density has been measured for oxygen reduction...

  19. Computer-based medical education in Benha University, Egypt: knowledge, attitude, limitations, and suggestions.

    Science.gov (United States)

    Bayomy, Hanaa; El Awadi, Mona; El Araby, Eman; Abed, Hala A

    2016-12-01

    Computer-assisted medical education has been developed to enhance learning and enable high-quality medical care. This study aimed to assess computer knowledge and attitude toward the inclusion of computers in medical education among second-year medical students in Benha Faculty of Medicine, Egypt, to identify limitations, and obtain suggestions for successful computer-based learning. This was a one-group pre-post-test study, which was carried out on second-year students in Benha Faculty of Medicine. A structured self-administered questionnaire was used to compare students' knowledge, attitude, limitations, and suggestions toward computer usage in medical education before and after the computer course to evaluate the change in students' responses. The majority of students were familiar with use of the mouse and keyboard, basic word processing, internet and web searching, and e-mail both before and after the computer course. The proportion of students who were familiar with software programs other than the word processing and trouble-shoot software/hardware was significantly higher after the course (Peducation, downloading lecture handouts, and computer-based exams (Peducation (Pcampus; all would support computer-assisted medical education. Medical students in Benha University are computer literate, which allows for computer-based medical education. Staff training, provision of computer labs, and internet access are essential requirements for enhancing computer usage in medical education in the university.

  20. The current status of knowledge of herbal medicine and medicinal plants in Fiche, Ethiopia.

    Science.gov (United States)

    d'Avigdor, Elizabeth; Wohlmuth, Hans; Asfaw, Zemede; Awas, Tesfaye

    2014-05-06

    A majority of Ethiopians rely on traditional medicine as their primary form of health care, yet they are in danger of losing both their knowledge and the plants they have used as medicines for millennia. This study, conducted in the rural town of Fiche in Ethiopia, was undertaken with the support of Southern Cross University (SCU) Australia, Addis Ababa University (AAU) Ethiopia, and the Ethiopian Institute of Biodiversity (EIB), Ethiopia. The aim of this study, which included an ethnobotanical survey, was to explore the maintenance of tradition in the passing on of knowledge, the current level of knowledge about medicinal herbs and whether there is awareness and concern about the potential loss of both herbal knowledge and access to traditional medicinal plants. This study was conducted using an oral history framework with focus groups, unstructured and semi-structured interviews, field-walk/discussion sessions, and a market survey. Fifteen people were selected via purposeful and snowball sampling. Analysis was undertaken using a grounded theory methodology. Fourteen lay community members and one professional herbalist provided information about 73 medicinal plants used locally. An ethnobotanical survey was performed and voucher specimens of 53 of the plants, representing 33 families, were collected and deposited at the EIB Herbarium. The community members are knowledgeable about recognition of medicinal plants and their usage to treat common ailments, and they continue to use herbs to treat sickness as they have in the past. A willingness to share knowledge was demonstrated by both the professional herbalist and lay informants. Participants are aware of the threat to the continued existence of the plants and the knowledge about their use, and showed willingness to take steps to address the situation. There is urgent need to document the valuable knowledge of medicinal herbs in Ethiopia. Ethnobotanical studies are imperative, and concomitant sustainable programmes

  1. Current knowledge on helicobacter pylori infection in end stage renal disease patients

    Directory of Open Access Journals (Sweden)

    Khedmat Hossein

    2009-01-01

    Full Text Available Gastric infection with Helicobacter Pylori in end-stage renal disease patients is of rele-vance because of its potential impact on the quality of life as well as morbidity and mortality of patients. Existed data on the issue are controversial, and we attempt in this article to evaluate the available data to approach extended perception of the current knowledge on the epidemiology, relevance, and optimum therapeutic strategies.

  2. Preliminary study of Korean orthodontic residents' current concepts and knowledge of cleft lip and palate management

    OpenAIRE

    Cho, Il-Sik; Shin, Hyo-Keun; Baek, Seung-Hak

    2012-01-01

    Objective A national survey was conducted to assess orthodontic residents' current concepts and knowledge of cleft lip and palate (CLP) management in Korea. Methods A questionnaire consisting of 7 categories and 36 question items was distributed to 16 senior chief residents of orthodontic department at 11 dental university hospitals and 5 medical university hospitals in Korea. All respondents completed the questionnaires and returned them. Results All of the respondents reported that they bel...

  3. Protection Principle for a DC Distribution System with a Resistive Superconductive Fault Current Limiter

    Directory of Open Access Journals (Sweden)

    Shimin Xue

    2015-05-01

    Full Text Available A DC distribution system, which is suitable for access to distributed power generation and DC loads, is one of the development directions in power systems. Furthermore, it could greatly improve the energy efficiency and reduce the loss of power transportation. The huge short circuit current is always a great threat to the safety of the components, especially the capacitors and diodes. A resistive superconductive fault current limiter (SFCL, which could respond quickly once a fault happens and limit the fault current to a relatively low level, becomes a good solution to this problem. In this paper, the operational principle of the resistive SFCL is introduced first, and then, the DC short-circuit fault characteristic of the DC distribution system with the SFCL is analyzed and the effectiveness of the SFCL verified. In order to realize the selectivity of the protection in the DC distribution system with SFCL, a new transient current protection principle based on Ip (the peak value of the current and tp (the transient time that the current takes to reach its peak value is proposed. Finally, a model of a 10-kV DC distribution system with an SFCL is established and simulated in PSCAD/METDC. Simulation results have demonstrated the validity of the analysis and protection principle.

  4. Virtual Impedance Based Fault Current Limiters for Inverter Dominated AC Microgrids

    DEFF Research Database (Denmark)

    Lu, Xiaonan; Wang, Jianhui; Guerrero, Josep M.

    2017-01-01

    In this paper, a virtual impedance based fault current limiter (VI-FCL) is proposed for islanded microgrids comprised of multiple inverter interfaced distributed generators (DGs). Considering the increased fault current capability induced by high penetration of renewable energy sources (RESs), FCLs...... are employed to suppress the fault current and the subsequent oscillation and even instability in the modern distribution network with microgrids. In this study, rather than involving extra hardware equipment, the functionality of FCL is achieved in the control diagram of DG inverters by employing additional...... virtual impedance control loops. The proposed VI-FCL features flexible and low-cost implementation and can effectively suppress the fault current and the oscillation in the following fault restoration process in AC microgrids. The systematic model of the inverter dominated AC microgrid is derived...

  5. Impact and Limitations Deriving from Basel II within the Context of the Current Financial Crisis

    Directory of Open Access Journals (Sweden)

    Oana Miruna DĂNILĂ

    2012-06-01

    Full Text Available The Banking sector risk management framework, geared towards maintaining a solid capital adequacy level, has witnessed a permanent evolution, determined by the global economic and financial reality.Basel II has brought an improvement of the risk management framework by adding minimum capital levels corresponding to market and operational risk and by the introduction of internal rating models. However the current crisis has brought forward some adverse effects as well as limitations.This paper analyses the evolution of prudential rules and regulations introduced by Basel II and their impact on the banking system together with outlining certain limitations.

  6. Progress in American Superconductor’s HTS wire and optimization for fault current limiting systems

    Energy Technology Data Exchange (ETDEWEB)

    Malozemoff, Alexis P., E-mail: amalozemoff@amsc.com

    2016-11-15

    Highlights: • AMSC HTS wire critical current needed for rotating machinery is doubled by 16 MeV Au irradiation. • Nonuniformity of HTS wires in power devices causes hot spot formation during power system faults. • Lower normal-state resistivity and critical current lower HTS wire hot spot heating during faults. • HTS wire hot spot heating in HTS cables during faults must stay below lN{sub 2} bubble nucleation point. • HTS wire can be designed to meet hot spot heating limits in fault current limiting cables. - Abstract: American Superconductor has developed composite coated conductor tape-shaped wires using high temperature superconductor (HTS) on a flexible substrate with laminated metal stabilizer. Such wires enable many applications, each requiring specific optimization. For example, coils for HTS rotating machinery require increased current density J at 25–50 K. A collaboration with Argonne, Brookhaven and Los Alamos National Laboratories and several universities has increased J using an optimized combination of precipitates and ion irradiation defects in the HTS. Major commercial opportunities also exist to enhance electric power grid resiliency by linking substations with distribution-voltage HTS power cables [10]. Such links provide alternative power sources if one substation's transmission-voltage power is compromised. But they must also limit fault currents which would otherwise be increased by such distribution-level links. This can be done in an HTS cable, exploiting the superconductor-to-resistive transition when current exceeds the wires’ critical J. A key insight is that such transitions are usually nonuniform; so the wire must be designed to prevent localized hot spots from damaging the wire or even generating gas bubbles in the cable causing dielectric breakdown. Analysis shows that local heating can be minimized by increasing the composite tape's total thickness, decreasing its total resistance in the normal state and

  7. Predicting the behavioural impact of transcranial direct current stimulation: issues and limitations

    Directory of Open Access Journals (Sweden)

    Archy Otto De Berker

    2013-10-01

    Full Text Available The transcranial application of weak currents to the human brain has enjoyed a decade of success, providing a simple and powerful tool for non-invasively altering human brain function. However, our understanding of current delivery and its impact upon neural circuitry leaves much to be desired. We argue that the credibility of conclusions drawn with tDCS is contingent upon realistic explanations of how tDCS works, and that our present understanding of tDCS limits the technique’s use to localize function in the human brain. We outline two central issues where progress is required: the localization of currents, and predicting their functional consequence. We encourage experimenters to eschew simplistic explanations of mechanisms of transcranial current stimulation. We suggest the use of individualized current modelling, together with computational neurostimulation to inform mechanistic frameworks in which to interpret the physiological impact of tDCS. We hope that through mechanistically richer descriptions of current flow and action, insight into the biological processes by which transcranial currents influence behaviour can be gained, leading to more effective stimulation protocols and empowering conclusions drawn with tDCS.

  8. Hysteresis current control of single-phase shunt active power filter using frequency limitation

    Energy Technology Data Exchange (ETDEWEB)

    Antchev, M.H.; Petkova, M.P. [Technical Univ. of Sofia, Sofia (Bulgaria); Kostov, A. [Fadata Ltd., Sofia (Bulgaria)]|[Technical Univ. of Sofia, Sofia (Bulgaria). Dept. of Power Electronics

    2007-07-01

    The hysterisis-current control of a single phase shunt active power filter (APF) was examined with particular reference to the frequency limitation that occurs when power devices are switched over. This limitation increases the stability to electromagnetic influences and facilitates the filtration of radio interference to the source network. Computer simulation results were presented along with results from an experimental oscilogramme displaying the source voltage and current under APF operation. The filter operation was performed under two types of loads. The first was a linear load representing active and inductive type load, while the second was a non-linear load representing a single-phase bridge uncontrolled rectifier with active-capacitive type load. APFs minimized harmonics in electrical networks and were shown to be an effective means for improving electromagnetic compatibility in electrical devices with low power factor. 10 refs., 8 figs.

  9. A dulal-functional medium voltage level DVR to limit downstream fault currents

    DEFF Research Database (Denmark)

    Blaabjerg, Frede; Li, Yun Wei; Vilathgamuwa, D. Mahinda

    2007-01-01

    on the other parallel feeders connected to PCC. Furthermore, if not controlled properly, the DVR might also contribute to this PCC voltage sag in the process of compensating the missing voltage, thus further worsening the fault situation. To limit the flow of large line currents, and therefore restore the PCC......, the DVR will therefore be tasked to mitigate even more faults involving downstream loads. Large fault currents would flow through the DVR during a downstream fault before the opening of a circuit breaker. This will cause the voltage at point of common coupling (PCC) to drop, which would affect the loads...... voltage as well as protect the DVR system components, a downstream fault limiting function is proposed and integrated in the DVR operation. A flux-charge-model feedback algorithm is implemented so that the DVR would act as a large virtual inductance in series with the distribution feeder in fault...

  10. Survival in extreme environments – on the current knowledge of adaptations in tardigrades

    DEFF Research Database (Denmark)

    Møbjerg, Nadja; Halberg, Kenneth Agerlin; Jørgensen, Aslak

    2011-01-01

    of the tardigrades and highlight species that are currently used as models for physiological and molecular investigations. Tardigrades are uniquely adapted to a range of environmental extremes. Cryptobiosis, currently referred to as a reversible ametabolic state induced by e.g. desiccation, is common especially...... among limno-terrestrial species. It has been shown that the entry and exit of cryptobiosis may involve synthesis of bioprotectants in the form of selective carbohydrates and proteins as well as high levels of antioxidant enzymes and other free radical scavengers. However, at present a general scheme...... to below )20 C, presumably relying on efficient DNA repair mechanisms and osmoregulation. This review summarizes the current knowledge on adaptations found among tardigrades, and presents new data on tardigrade cell numbers and osmoregulation....

  11. [Housing quality and its health impact in Italy: current knowledge, methodological issues, new evaluation models].

    Science.gov (United States)

    Capasso, Lorenzo; Capolongo, Stefano; Flacco, Maria Elena; Manzoli, Lamberto; Buffoli, Maddalena

    2014-01-01

    A literature search was performed to evaluate the current state of knowledge regarding housing quality in Italy and the adequacy of methods used to assess it. The simple adoption of current criteria required by national and local legislation for the evaluation of dwellings seems to be inadequate, because some crucial parameters, including radon testing and evaluation of accessibility are not considered. Also, current assessment methods have been used exclusively at the local level, and the health impact of housing quality in Italy has never been estimated. There is a strong need for more sensitive methods of evaluation of indoor environments, to be validated on large and representative samples. The authors discuss two possible alternative models which may ensure a multifactorial, holistic assessment of the quality of housing spaces, also by including an evaluation of psycho-social components.

  12. Proton transport inside the biofilm limits electrical current generation by anode-respiring bacteria.

    Science.gov (United States)

    Torres, César I; Kato Marcus, Andrew; Rittmann, Bruce E

    2008-08-01

    Anode-respiring bacteria (ARB) in a biofilm anode carry out an oxidation half-reaction of organic matter, producing an electrical current from renewable biomass, including wastes. At the same time, ARB produce protons, usually one proton for every electron. Our study shows how current density generated by an acclimated ARB biofilm was limited by proton transport out of the biofilm. We determined that, at high current densities, protons were mainly transported out of the biofilm by protonating the conjugate base of the buffer system; the maximum current generation was directly related to the transport of the buffer, mainly by diffusion, into and out of the biofilm. With non-limiting acetate concentrations, the current density increased with higher buffer concentrations, going from 2.21 +/- 0.02 A m(-2) with 12.5-mM phosphate buffer medium to 9.3 +/- 0.4 A m(-2) using a 100-mM phosphate buffer at a constant anode potential of E(anode) = -0.35 V versus Ag/AgCl. Increasing the concentration of sodium chloride in the medium (0-100 mM) increased current density by only 15%, indicating that ion migration was not as important as diffusion of phosphate inside the biofilm. The current density also varied strongly with medium pH as a result of the buffer speciation: The current density was 10.0 +/- 0.8 A m(-2) at pH 8, and the pH giving one-half the maximum rate was 6.5. A j-V curve analysis using 100 mM phosphate buffer showed a maximum current density of 11.5 +/- 0.9 A m(-2) and half-saturation potential of -0.414 V versus Ag/AgCl, a value that deviated only slightly from the standard acetate potential, resulting in small anode-potential losses. We discuss the implications of the proton-transport limitation in the field of microbial fuel cells and microbial electrolytic cells. (c) 2008 Wiley Periodicals, Inc.

  13. Managing player load in professional rugby union: a review of current knowledge and practices.

    Science.gov (United States)

    Quarrie, Kenneth L; Raftery, Martin; Blackie, Josh; Cook, Christian J; Fuller, Colin W; Gabbett, Tim J; Gray, Andrew J; Gill, Nicholas; Hennessy, Liam; Kemp, Simon; Lambert, Mike; Nichol, Rob; Mellalieu, Stephen D; Piscione, Julien; Stadelmann, Jörg; Tucker, Ross

    2017-03-01

    The loads to which professional rugby players are subjected has been identified as a concern by coaches, players and administrators. In November 2014, World Rugby commissioned an expert group to identify the physical demands and non-physical load issues associated with participation in professional rugby. To describe the current state of knowledge about the loads encountered by professional rugby players and the implications for their physical and mental health. The group defined 'load' as it relates to professional rugby players as the total stressors and demands applied to the players. In the 2013-2014 seasons, 40% of professional players appeared in 20 matches or more, and 5% of players appeared in 30 matches or more. Matches account for ∼5-11% of exposure to rugby-related activities (matches, team and individual training sessions) during professional competitions. The match injury rate is about 27 times higher than that in training. The working group surmised that players entering a new level of play, players with unresolved previous injuries, players who are relatively older and players who are subjected to rapid increases in load are probably at increased risk of injury. A mix of 'objective' and 'subjective' measures in conjunction with effective communication among team staff and between staff and players was held to be the best approach to monitoring and managing player loads. While comprehensive monitoring holds promise for individually addressing player loads, it brings with it ethical and legal responsibilities that rugby organisations need to address to ensure that players' personal information is adequately protected. Administrators, broadcasters, team owners, team staff and the players themselves have important roles in balancing the desire to have the 'best players' on the field with the ongoing health of players. In contrast, the coaching, fitness and medical staff exert significant control over the activities, duration and intensity of training

  14. On Relativistic Space Charge Limited Current in Planar, Cylindrical, and Spherical Diodes

    Science.gov (United States)

    2016-07-01

    Phys. Rev., vol . 21, p. 450, 1923. [3] I. Langmuir and K. B. Blodgett, “Currents limited by space charge between coaxial cylinders,” Phys. Rev., vol . 22 ...Andrew Greenwood, et al. Air Force Research Laboratory Department of Nuclear Engineering 3550 Aberdeen Avenue SE Radiological ...Force Resear ch Laboratory 3550 Aberdeen Avenue SE Kirtland AFB, NM 87117-5776 Department of Nuclear Engineering and Radiological Sciences

  15. Transformation of current limiting effect into varistor effect in tin dioxide based ceramics

    Energy Technology Data Exchange (ETDEWEB)

    Bondarchuk, A N; Glot, A B [Universidad Tecnologica de la Mixteca, Huajuapan de Leon, Oaxaca, C.P. 69000 (Mexico)], E-mail: alexbond@mixteco.utm.mx

    2008-09-07

    The current limiting effect and its transformation into the varistor effect were found in SnO{sub 2}-Co{sub 3}O{sub 4}-Nb{sub 2}O{sub 5}-Cr{sub 2}O{sub 3} ceramics sintered at relatively low temperatures 1100-1200 {sup 0}C. Results of electrical measurements in oxidizing and inert atmosphere are explained in terms of the modified barrier model.

  16. Sensory perception in cetaceans: Part I – Current knowledge about dolphin senses as a representative species

    Directory of Open Access Journals (Sweden)

    Dorothee eKremers

    2016-05-01

    Full Text Available A large part of the literature on sensory perception and behavior in dolphins is devoted to its well-developed vocal and echolocation abilities. In this review, we aim to augment current knowledge by examining the literature on dolphins’ entire Merkwelt (which refers to everything a subject perceives, creating a crucial part of the subject’s Umwelt. We will show that despite extensive knowledge on audition, aspects such as context relatedness, the social function of vocalizations or socio-sexual recognition, remain poorly understood. Therefore, we propose areas for further lines of investigation. Recent studies have shown that the sensory world of dolphins might well be much more diverse than initially thought. Indeed, although underwater and aerial visual systems differ in dolphins, they have both been shown to be important. Much debated electro- and magnetoreception appear to be functional senses according to recent studies. Finally, another neglected area is chemoreception. We will summarize neuroanatomical and physiological data on olfaction and taste, as well as corresponding behavioral evidence. Taken together, we will identify a number of technical and conceptual reasons for why chemosensory data appear contradictory, which is much debated in the literature. In summary, this article aims to provide both an overview of the current knowledge on dolphin perception, but also offer a basis for further discussion and potential new lines of research.

  17. Effects of a voltage compensation type active superconducting fault current limiter on distance relay protection

    Science.gov (United States)

    Chen, L.; Tang, Y. J.; Shi, J.; Ren, L.; Song, M.; Cheng, S. J.; Hu, Y.; Chen, X. S.

    2010-11-01

    On the basis of a voltage compensation type active superconducting fault current limiter (SFCL) proposed in previous work, the effects of this type SFCL on distance relay protection are studied in this paper. Under the condition that the active SFCL is placed behind the relay element, its current-limiting impedance will be added into the measured impedance between the relay and the fault points. As a result, in order to prevent the refused operation of the relay, the measured impedance should be revised. According to the three different operation modes of the active SFCL, we present the corresponding three modified formulas. Furthermore, using MATLAB, the model of the dual-source power system with the active SFCL is built, and the impacts of the active SFCL on the distance relay protection are studied in detail under the different current-limiting modes and fault distances. The simulation results show that: without using the modified formulas, the introduction of the active SFCL will reduce the protection distance of the relay, and in the case that the modified formulas are adopted, the three modes of the active SFCL will not affect the measured impedance of the relay, and further the validities of the proposed modified formulas can be testified.

  18. Current components data from current meters from the NE Pacific (limit-180) from 1954-06-01 to 1970-06-01 (NODC Accession 7601441)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current components data were collected from current meters in the NE Pacific (limit-180). Data were collected by the Japanese Hydrographic Office from 01 June 1954...

  19. Current meter data from moored current meter casts in the Northeast Pacific (limit - 180) from 1992-06-12 to 1994-06-20 (NODC Accession 9700237)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current meter data were collected using moored current meter casts in the Northeast Pacific (limit - 180) from June 12, 1992 to June 20, 1994. Data were submitted by...

  20. Current Limitations and Recommendations to Improve Testing for the Environmental Assessment of Endocrine Active Substances

    DEFF Research Database (Denmark)

    Coady, Katherine K; Biever, Ronald C; Denslow, Nancy D

    2017-01-01

    In this paper existing regulatory frameworks and test systems for assessing potential endocrine-active chemicals are described, and associated challenges discussed, along with proposed approaches to address these challenges. Regulatory frameworks vary somewhat across geographies, but all basically...... evaluate whether a chemical possesses endocrine activity and whether this activity can result in adverse outcomes either to humans or the environment. Current test systems include in silico, in vitro and in vivo techniques focused on detecting potential endocrine activity, and in vivo tests that collect...... apical data to detect possible adverse effects. These test systems are currently designed to robustly assess endocrine activity and/or adverse effects in the estrogen, androgen, and thyroid hormone signaling pathways; however, there are some limitations of current test systems for evaluating endocrine...

  1. Enhancing LVRT of DFIG by Using a Superconducting Current Limiter on Rotor Circuit

    Directory of Open Access Journals (Sweden)

    Flávio Oliveira

    2015-12-01

    Full Text Available This paper have studied the dynamic of a 2.0 MW Doubly Fed Induction Generator (DFIG during a severe voltage sag. Using the dynamic model of a DFIG, it was possible to determine the current, Electromagnetic Force and flux behavior during three-phase symmetrical voltage dip. Among the technologies of wind turbines the DFIG is widely employed; however, this machine is extremely susceptible to disturbances from the grid. In order to improve DFIG Low Voltage Ride-Through (LVRT, it is proposed a novel solution, using Superconducting Current Limiter (SCL in two arrangements: one, the SCL is placed between the machine rotor and the rotor side converter (RSC, and another placed in the RSC DC-link. The proposal is validated through simulation using PSCAD™/EMTDC™ and according to requirements of specific regulations. The analysis ensure that both SCL arrangements behave likewise, and are effective in decrement the rotor currents during the disturbance.

  2. Current Limitations and Recommendations to Improve Testing for the Environmental Assessment of Endocrine Active Substances

    DEFF Research Database (Denmark)

    Coady, Katherine K; Biever, Ronald C; Denslow, Nancy D

    2016-01-01

    In this paper existing regulatory frameworks and test systems for assessing potential endocrine-active chemicals are described, and associated challenges discussed, along with proposed approaches to address these challenges. Regulatory frameworks vary somewhat across geographies, but all basically...... evaluate whether a chemical possesses endocrine activity and whether this activity can result in adverse outcomes either to humans or the environment. Current test systems include in silico, in vitro and in vivo techniques focused on detecting potential endocrine activity, and in vivo tests that collect...... apical data to detect possible adverse effects. These test systems are currently designed to robustly assess endocrine activity and/or adverse effects in the estrogen, androgen, and thyroid hormone signaling pathways; however, there are some limitations of current test systems for evaluating endocrine...

  3. Facilitation of Function and Manipulation Knowledge of Tools Using Transcranial Direct Current Stimulation (tDCS

    Directory of Open Access Journals (Sweden)

    Ryo Ishibashi

    2018-01-01

    Full Text Available Using a variety of tools is a common and essential component of modern human life. Patients with brain damage or neurological disorders frequently have cognitive deficits in their recognition and manipulation of tools. In this study, we focused on improving tool-related cognition using transcranial direct current stimulation (tDCS. Converging evidence from neuropsychology, neuroimaging and non- invasive brain stimulation has identified the anterior temporal lobe (ATL and inferior parietal lobule (IPL as brain regions supporting action semantics. We observed enhanced performance in tool cognition with anodal tDCS over ATL and IPL in two cognitive tasks that require rapid access to semantic knowledge about the function or manipulation of common tools. ATL stimulation improved access to both function and manipulation knowledge of tools. The effect of IPL stimulation showed a trend toward better manipulation judgments. Our findings support previous studies of tool semantics and provide a novel approach for manipulation of underlying circuits.

  4. Rapid Detection Strategies for the Global Threat of Zika Virus: Current State, New Hypotheses and Limitations

    Directory of Open Access Journals (Sweden)

    Shruti Shukla

    2016-10-01

    Full Text Available The current scenario regarding the widespread Zika virus (ZIKV has resulted in numerous diagnostic studies, specifically in South America and in locations where there is frequent entry of travelers returning from ZIKV-affected areas, including pregnant women with or without clinical symptoms of ZIKV infection. The World Health Organization, WHO, announced that millions of cases of ZIKV are likely to occur in the United States of America in the near future. This situation has created an alarming public health emergency of international concern requiring the detection of this life-threatening viral candidate due to increased cases of newborn microcephaly associated with ZIKV infection. Hence, this review reports possible methods and strategies for the fast and reliable detection of ZIKV with particular emphasis on current updates, knowledge and new hypotheses that might be helpful for medical professionals in poor and developing countries that urgently need to address this problem. In particular, we emphasize liposome-based biosensors. Although these biosensors are currently among the less popular tools for human disease detection, they have become useful tools for the screening and detection of pathogenic bacteria, fungi and viruses because of their versatile advantageous features compared to other sensing devices. This review summarizes the currently available methods employed for the rapid detection of ZIKV and suggests an innovative approach involving the application of a liposome-based hypothesis for the development of new strategies for ZIKV detection and their use as effective biomedicinal tools.

  5. Current practice patterns and knowledge among gynecologic surgeons of InterStim® programming after implantation.

    Science.gov (United States)

    Hobson, Deslyn T G; Gaskins, Jeremy T; Frazier, LaTisha; Francis, Sean L; Kinman, Casey L; Meriwether, Kate V

    2017-10-03

    The objective of this study was to describe surgeons' current practices in InterStim® programming after initial implantation and their knowledge of programming parameters. We hypothesized that surgeons performing their own reprogramming would have increased knowledge. We administered a written survey to attendees at the Society of Gynecologic Surgeons Scientific Meeting and analyzed those on which surgeons indicated they offer InterStim® care. The survey queried surgeon characteristics, experience with InterStim® implantation and programming, and clinical opinions regarding reprogramming and tested six knowledge-based questions about programming parameters. Correct response to all six questions was the primary outcome. One hundred and thirty-five of 407 (33%) attendees returned the survey, of which 99 met inclusion criteria. Most respondents (88 of 99; 89%) were between 36 and 60 years, 27 (73%) were women, 76 (77%) practiced in a university setting, and 76 (77%) were trained in Female Pelvic Medicine and Reconstructive Surgery (FPMRS). Surgeons who had InterStim® programming training were more likely to perform their own programming [15/46 (32%) vs 6/47 (13%), p = 0.03]. Most answered all knowledge-based questions correctly (62/90, 69%); no surgeon characteristics were significantly associated with this outcome. Most surgeons cited patient comfort (71/80, 89%) and symptom relief (64/80, 80%) as important factors when reprogramming, but no prevalent themes emerged on how and why surgeons change certain programming parameters. Surgeons who had formal InterStim® programming training are more likely to perform programming themselves. No surgeon characteristic was associated with improved programming knowledge. We found that surgeons prioritize patient comfort and symptoms when deciding to reprogram.

  6. Leber hereditary optic neuropathy - historical report in comparison with the current knowledge.

    Science.gov (United States)

    Piotrowska, Agnieszka; Korwin, Magdalena; Bartnik, Ewa; Tońska, Katarzyna

    2015-01-15

    Leber hereditary optic neuropathy (LHON) is a genetic, maternally inherited disease caused by point mutations in the mitochondrial genome. LHON patients present with sudden, painless and usually bilateral loss of vision caused by optic nerve atrophy. The first clinical description of the disease was made by Theodor Leber, a German ophthalmologist, in 1871. Here we present his thorough notes about members of four families and their pedigrees. We also provide insights into the current knowledge about LHON pathology, genetics and treatment in comparison with Leber's findings. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Global forces and local currents in Argentina's science policy crossroads: restricted access or open knowledge

    Directory of Open Access Journals (Sweden)

    Horacio Javier Etchichury

    2014-11-01

    Full Text Available The article describes the tensions between two competing approaches to scientific policy in Argentina. The traditional vision favors autonomous research. The neoliberal conception fosters the link between science and markets. In the past few years, a neodevelopmentalist current also tries to stress relevance of scientific research. Finally, the article describes how the Open Access movement has entered the debate. The World Bank intervention and the human rights dimension of the question are discussed in depth. The article introduces the notion of open knowledge as a guiding criterion to design a human-rights based scientific policy.

  8. Denervated muscles in humans: limitations and problems of currently used functional electrical stimulation training protocols.

    Science.gov (United States)

    Kern, Helmut; Hofer, Christian; Mödlin, Michaela; Forstner, Claudia; Raschka-Högler, Doris; Mayr, Winfried; Stöhr, Hans

    2002-03-01

    Prior clinical work showed that electrical stimulation therapy with exponential current is able to slow down atrophy and maintain the muscle during nonpermanent flaccid paralysis. However, exponential currents are not sufficient for long-term therapy of denervated degenerated muscles (DDMs). We initiated a European research project investigating the rehabilitation strategies in humans, but also studying the underlying basic scientific knowledge of muscle regeneration from satellite cells or myoblast activity in animal experiments. In our prior study, we were able to show that high-intensity stimulation of DDMs is possible. At the beginning of training, only single muscle twitches can be elicited by biphasic pulses with durations of 120-150 ms. Later, tetanic contraction of the muscle with special stimulation parameters (pulse duration of 30-50 ms, stimulation frequency of 16-25 Hz, pulse amplitudes of up to 250 mA) can improve the structural and metabolic state of the DDMs. Because there are no nerve endings for conduction of stimuli, large-size, anatomically shaped electrodes are used. This ensures an even contraction of the whole muscle. Contrary to the current clinical knowledge, we were able to stimulate and train denervated muscle 15-20 years after denervation. The estimated amount of muscle fibers that have to be restored is about 2-4 million fibers in each m. quadriceps. To rebuild such a large number of muscle fibers takes up to 3-4 years. Despite constant stimulation parameters and training protocols, there is a high variation in the developed contraction force and fatigue resistance of the muscle during the first years of functional electrical stimulation.

  9. Power flow analysis and optimal locations of resistive type superconducting fault current limiters.

    Science.gov (United States)

    Zhang, Xiuchang; Ruiz, Harold S; Geng, Jianzhao; Shen, Boyang; Fu, Lin; Zhang, Heng; Coombs, Tim A

    2016-01-01

    Based on conventional approaches for the integration of resistive-type superconducting fault current limiters (SFCLs) on electric distribution networks, SFCL models largely rely on the insertion of a step or exponential resistance that is determined by a predefined quenching time. In this paper, we expand the scope of the aforementioned models by considering the actual behaviour of an SFCL in terms of the temperature dynamic power-law dependence between the electrical field and the current density, characteristic of high temperature superconductors. Our results are compared to the step-resistance models for the sake of discussion and clarity of the conclusions. Both SFCL models were integrated into a power system model built based on the UK power standard, to study the impact of these protection strategies on the performance of the overall electricity network. As a representative renewable energy source, a 90 MVA wind farm was considered for the simulations. Three fault conditions were simulated, and the figures for the fault current reduction predicted by both fault current limiting models have been compared in terms of multiple current measuring points and allocation strategies. Consequently, we have shown that the incorporation of the E - J characteristics and thermal properties of the superconductor at the simulation level of electric power systems, is crucial for estimations of reliability and determining the optimal locations of resistive type SFCLs in distributed power networks. Our results may help decision making by distribution network operators regarding investment and promotion of SFCL technologies, as it is possible to determine the maximum number of SFCLs necessary to protect against different fault conditions at multiple locations.

  10. Management of newborn infant born to mother suffering from tuberculosis: current recommendations & gaps in knowledge.

    Science.gov (United States)

    Mittal, Hema; Das, Saurabhi; Faridi, M M A

    2014-07-01

    Tuberculosis (TB) is a global disease with increase in concern with growing morbidity and mortality after drug resistance and co-infection with HIV. Mother to neonatal transmission of disease is well known. Current recommendations regarding management of newborns of mothers with tuberculosis are variable in different countries and have large gaps in the knowledge and practices. We compare and summarize here current recommendations on management of infants born to mothers with tuberculosis. Congenital tuberculosis is diagnosed by Cantwell criteria and treatment includes three or four anti-tubercular drug regimen. Prophylaxis with isoniazid (3-6 months) is recommended in neonates born to mother with TB who are infectious. Breastfeeding should be continued in these neonates and isolation is recommended only till mother is infectious, has multidrug resistant tuberculosis or non adherent to treatment. BCG vaccine is recommended at birth or after completion of prophylaxis (3-6 months) in all neonates.

  11. Adequacy of Physicians Knowledge Level of Cardiopulmonary Resuscitation to Current Guidelines

    Directory of Open Access Journals (Sweden)

    Ümmu Kocalar

    2016-01-01

    Full Text Available Aim: The purpose of this study is to test the level of information on CPR and suitability to current application of the phsicians practicing in hospital ANEAH. Material and Method: The form of a test of 20 questions fort his purpose has been prepared in accordance with the 2010 AHA-ERC CPR guidelines. This form distributed to volunteer physicians to fill in. A total of 173 physicians agreed to participate in he study. The results were analyzed statistically and tried to determine the factors affecting the level of information. Results:According to the results of the study physicians gender, age and the total duration of physicians and medical asistance doesn%u2019t affect the level of information. The number of CPR within 1 month positively affect the level of knowledge. The number of theoretical and practical training in medical school, have taken the positive impact the level of knowledge of physicians. The training period after graduation, significantly increased the level of physicians information. The order of these training sessions with the asistant courses, congress, seminars and lessions on the sempozims are effective. Discussion: CPR trainig programs for physicians should be standardized, updated and expanded. Recurent in-service trainig should be provided to increase phsicians knowledge on skills.

  12. Advantages and Limitations of Current Biomarker Research: From Experimental Research to Clinical Application.

    Science.gov (United States)

    Kim, Seung-Hyun; Weiß, Christel; Hoffmann, Ursula; Borggrefe, Martin; Akin, Ibrahim; Behnes, Michael

    2017-01-01

    Biomarkers are indispensable tools for screening, diagnosis, and prognosis in cardiovascular diseases and their clinical application increases steadily. As cardiovascular diseases include various pathophysiological processes, no single biomarker, even natriuretic peptides, can be regarded as ideal fulfilling all necessary criteria for a comprehensive diagnostic or prognostic assessment revealing optimal clinical application. Hence, multi-marker approaches using different biomarkers reflecting different pathophysiologies were highlighted recently. Advances in biomedical technologies expanded the spectrum of novel blood-derived biomarkers, such as micro-RNA (miRNA) or "omics"- data potentially providing a more advanced knowledge about pathogenesis of cardiovascular disease. This review describes the advantages and limitations of blood circulating biomarkers with regard to proteins, metabolomics and transcriptional level both within single as well as multi-marker strategies. Moreover, their usefulness is focused on clinical decision-making in cardiovascular diseases. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  13. Segmented Limiter Biasing and Toroidal Current Drive on the STOR-M Tokamak

    Science.gov (United States)

    White, D.; Hirose, A.; Xiao, C.; Furkal, E.

    1996-11-01

    A segmented limiter has recently been installed on the upgraded STOR-M tokamak (R/a=46/12 cm, B_t<1 T, I_p<= 50 kA, barn_e=(0.5 - 1)×10^13 cm-3). The limiter consists of two sets of four stainless steel plates mounted back to back in a ceramic housing. Each plate is electrically isolated from its neighbours, and can be individually biased with respect to the chamber wall by one of eight independent capacitor banks (15 mF, 900 V). Using a voltage sweeper connected to a double probe, measurements of the DC value and fluctuation level in electron temperature and density will be taken, to reveal the effects of limiter biasing on the plasma parameters at the edge and in the SOL. In particular, poloidal asymmetry of plasma parameters under various biasing configurations will be studied. In addition, feasibility of driving toroidal current with the segmented limiter will be investigated.

  14. Biological determinants linking infant weight gain and child obesity: current knowledge and future directions.

    Science.gov (United States)

    Young, Bridget E; Johnson, Susan L; Krebs, Nancy F

    2012-09-01

    Childhood obesity rates have reached epidemic proportions. Excessive weight gain in infancy is associated with persistence of elevated weight status and later obesity. In this review, we make the case that weight gain in the first 6 mo is especially predictive of later obesity risk due to the metabolic programming that can occur early postpartum. The current state of knowledge regarding the biological determinants of excess infant weight gain is reviewed, with particular focus on infant feeding choice. Potential mechanisms by which different feeding approaches may program the metabolic profile of the infant, causing the link between early weight gain and later obesity are proposed. These mechanisms are likely highly complex and involve synergistic interactions between endocrine effects and factors that alter the inflammatory and oxidative stress status of the infant. Gaps in current knowledge are highlighted. These include a lack of data describing 1) what type of infant body fat distribution may impart risk and 2) how maternal metabolic dysfunction (obesity and/or diabetes) may affect milk composition and exert downstream effects on infant metabolism. Improved understanding and management of these early postnatal determinants of childhood obesity may have great impact on reducing its prevalence.

  15. Plasma-enhanced chemical vapor deposition for YBCO film fabrication of superconducting fault-current limiter

    Energy Technology Data Exchange (ETDEWEB)

    Jun, Byung Hyuk; Kim, Chan Joong

    2006-05-15

    Since the high-temperature superconductor of oxide type was founded, many researches and efforts have been performed for finding its application field. The YBCO superconducting film fabricated on economic metal substrate with uniform critical current density is considered as superconducting fault-current limiter (SFCL). There are physical and chemical processes to fabricate superconductor film, and it is understood that the chemical methods are more economic to deposit large area. Among them, chemical vapor deposition (CVD) is a promising deposition method in obtaining film uniformity. To solve the problems due to the high deposition temperature of thermal CVD, plasma-enhanced chemical vapor deposition (PECVD) is suggested. This report describes the principle and fabrication trend of SFCL, example of YBCO film deposition by PECVD method, and principle of plasma deposition.

  16. A Current Limiting Strategy to Improve Fault Ride-Through of Inverter Interfaced Autonomous Microgrids

    DEFF Research Database (Denmark)

    Sadeghkhani, Iman; Esmail Hamedani Golshan, Mohamad; Guerrero, Josep M.

    2017-01-01

    With high penetration of distributed energy resources (DER), fault management strategy is of great importance for the distribution network operation. The objective of this paper is to propose a current and voltage limiting strategy to enhance fault ride-through (FRT) capability of inverter......-based islanded microgrids (MGs) in which the effects of inverter control system and inverter topology (four/three-wire) are considered. A threephase voltage-sourced inverter (VSI) with multi-loop control system implemented in synchronous, stationary, and natural reference frames is employed in this study...... for both four- and three-wire configurations. The proposed strategy provides high voltage and current quality during overcurrent conditions, which is necessary for sensitive loads. Several time-domain simulation studies are conducted to investigate the FRT capability of the proposed strategy against both...

  17. High-temperature superconducting fault-current limiter - optimisation of superconducting elements

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    This report summarises the findings of a study initiated to continue the work of a DTI-LINK Collaborative Research Programme 'Enhancing the Properties of Bulk High Temperature Superconductors and their Potential Application as Fault Current Limiters (FCL). Details are given of computer modelling of the quenching process involving the transition from superconducting to normal conducting states undergone by the material when large currents are present. The design of compound elements, and a multi-element model are described along with FCL design covering distribution bus-coupler, embedded generator connection, larger generator connection, hazardous area safety, and interconnection to fault-prone network. The evaluation of thermal loss, test equipment and schedule, the optimised element, installed cost data, and the UK market are considered.

  18. Modeling space-charge-limited currents in organic semiconductors: Extracting trap density and mobility

    KAUST Repository

    Dacuña, Javier

    2011-11-28

    We have developed and have applied a mobility edge model that takes drift and diffusion currents to characterize the space-charge-limited current in organic semiconductors into account. The numerical solution of the drift-diffusion equation allows the utilization of asymmetric contacts to describe the built-in potential within the device. The model has been applied to extract information of the distribution of traps from experimental current-voltage measurements of a rubrene single crystal from Krellner showing excellent agreement across several orders of magnitude in the current. Although the two contacts are made of the same metal, an energy offset of 580 meV between them, ascribed to differences in the deposition techniques (lamination vs evaporation) was essential to correctly interpret the shape of the current-voltage characteristics at low voltage. A band mobility of 0.13cm 2V-1s-1 for holes is estimated, which is consistent with transport along the long axis of the orthorhombic unit cell. The total density of traps deeper than 0.1 eV was 2.2×1016cm -3. The sensitivity analysis and error estimation in the obtained parameters show that it is not possible to accurately resolve the shape of the trap distribution for energies deeper than 0.3 eV or shallower than 0.1 eV above the valence-band edge. The total number of traps deeper than 0.3 eV, however, can be estimated. Contact asymmetry and the diffusion component of the current play an important role in the description of the device at low bias and are required to obtain reliable information about the distribution of deep traps. © 2011 American Physical Society.

  19. Current limitations and recommendations to improve testing for the environmental assessment of endocrine active substances

    Science.gov (United States)

    Coady, Katherine K.; Biever, Ronald C.; Denslow, Nancy D.; Gross, Melanie; Guiney, Patrick D.; Holbech, Henrik; Karouna-Renier, Natalie K.; Katsiadaki, Ioanna; Krueger, Hank; Levine, Steven L.; Maack, Gerd; Williams, Mike; Wolf, Jeffrey C.; Ankley, Gerald T.

    2017-01-01

    In the present study, existing regulatory frameworks and test systems for assessing potential endocrine active chemicals are described, and associated challenges are discussed, along with proposed approaches to address these challenges. Regulatory frameworks vary somewhat across geographies, but all basically evaluate whether a chemical possesses endocrine activity and whether this activity can result in adverse outcomes either to humans or to the environment. Current test systems include in silico, in vitro, and in vivo techniques focused on detecting potential endocrine activity, and in vivo tests that collect apical data to detect possible adverse effects. These test systems are currently designed to robustly assess endocrine activity and/or adverse effects in the estrogen, androgen, and thyroid hormone signaling pathways; however, there are some limitations of current test systems for evaluating endocrine hazard and risk. These limitations include a lack of certainty regarding: 1) adequately sensitive species and life stages; 2) mechanistic endpoints that are diagnostic for endocrine pathways of concern; and 3) the linkage between mechanistic responses and apical, adverse outcomes. Furthermore, some existing test methods are resource intensive with regard to time, cost, and use of animals. However, based on recent experiences, there are opportunities to improve approaches to and guidance for existing test methods and to reduce uncertainty. For example, in vitro high-throughput screening could be used to prioritize chemicals for testing and provide insights as to the most appropriate assays for characterizing hazard and risk. Other recommendations include adding endpoints for elucidating connections between mechanistic effects and adverse outcomes, identifying potentially sensitive taxa for which test methods currently do not exist, and addressing key endocrine pathways of possible concern in addition to those associated with estrogen, androgen, and thyroid

  20. Identifying krill eggs in the central California current using novel multiplex PCR primers: Applications and limitations

    Science.gov (United States)

    Carrion, C. N.; Slesinger, E.; Marinovic, B.

    2016-02-01

    Euphausiids, otherwise known as krill, are an important link between primary producers and higher trophic levels within the central California current upwelling system. Euphausia pacifica and Thysanoessa spinifera, two of the most common euphausiid species along the central California coast, are both broadcast spawners and have some overlap in habitat, e.g. near marine life hotspots like the Monterey Bay and Gulf of Farallones. Species composition of euphausiid egg population within these regions is currently unknown. Distinct morphological differences between their eggs are lost once the egg dies or is preserved via formalin, alcohol, or freezing. In this project we designed genus specific DNA primers (mtCOI) for use in a multiplex PCR to distinguish among spawned euphausiid eggs of Euphausia spp. and Thysanoessa spp. in central California current surface waters. Effective and ineffective application of primers in a multiplex versus single-plex PCR is discussed, with an emphasis on primer design limitations in reference to the available barcoded regions of mitochondrial cytochrome oxidase subunit I (mtCOI) for each species in GenBank. This new protocol expands current monitoring efforts into sampling a non-swimming portion of the population which has the potential to improve euphausiid biomass estimates.

  1. Design, Test and Demonstration of Saturable Reactor High-Temperature Superconductor Fault Current Limiters

    Energy Technology Data Exchange (ETDEWEB)

    Darmann, Frank [Zenergy Power, Inc., Burlingame, CA (United States); Lombaerde, Robert [Zenergy Power, Inc., Burlingame, CA (United States); Moriconi, Franco [Zenergy Power, Inc., Burlingame, CA (United States); Nelson, Albert [Zenergy Power, Inc., Burlingame, CA (United States)

    2012-03-01

    Zenergy Power has successfully designed, built, tested, and installed in the US electrical grid a saturable reactor Fault Current Limiter. Beginning in 2007, first as SC Power Systems and from 2008 as Zenergy Power, Inc., ZP used DOE matching grant and ARRA funds to help refine the design of the saturated reactor fault current limiter. ZP ultimately perfected the design of the saturated reactor FCL to the point that ZP could reliably design a suitable FCL for most utility applications. Beginning with a very basic FCL design using 1G HTS for a coil housed in a LN2 cryostat for the DC bias magnet, the technology progressed to a commercial system that was offered for sale internationally. Substantial progress was made in two areas. First, the cryogenics cooling system progressed from a sub-cooled liquid nitrogen container housing the HTS coils to cryostats utilizing dry conduction cooling and reaching temperatures down to less than 20 degrees K. Large, round cryostats with warm bore diameters of 1.7 meters enabled the design of large tanks to hold the AC components. Second, the design of the AC part of the FCL was refined from a six legged spider design to a more compact and lighter design with better fault current limiting capability. Further refinement of the flux path and core shape led to an efficient saturated reactor design requiring less Ampere-turns to saturate the core. In conclusion, the development of the saturable reactor FCL led to a more efficient design not requiring HTS magnets and their associated peripheral equipment, which yielded a more economical product in line with the electric utility industry expectations. The original goal for the DOE funding of the ZP project Design, Test and Demonstration of Saturable Reactor High-Temperature Superconductor Fault Current Limiters was to stimulate the HTS wire industry with, first 1G, then 2G, HTS wire applications. Over the approximately 5 years of ZP's product development program, the amount of HTS

  2. Awareness and knowledge of ocular cancers in a resource-limited economy.

    Science.gov (United States)

    Ayanniyi, Abdulkabir A; Jamda, Abubakar M; Badmos, Kabir B; Adelaiye, Rabi S; Mahmoud, Abdulraheem O; Kyari, Fatima; Nwana, Edmund J

    2010-11-01

    To determine awareness and knowledge of ocular cancers in a resource-limited setting. A descriptive cross-sectional survey (2009) of 1,887 Nigerians using interviewer-administered questionnaire. Respondents were 55.6% males, and mean age was 30 years, SD 9.5. Most respondents (77.8%) had at least secondary education. Fewer respondents were aware of eye cancers (57.1%) compared to cancers in general (73.7%) (Pknowledge of patients having ocular cancers on sources other than hospital diagnosis. Of 148 respondents, 16.2% were related to 'patients' they knew had ocular cancers. There were 202 respondents who indicated challenges to accessing orthodox medical eye care services by ocular cancer patients as high cost 55.5%, long waiting period 23.3%, long distance 15.4% and poor attitude of health workers 5.9%. Awareness of ocular cancers compared to other cancers is low. Misconceptions on the causes of ocular cancers exist. Public ocular cancers health education can enhance awareness. The need to address barriers to accessing eye care is underscored.

  3. Carbohydrate ingestion during team games exercise: current knowledge and areas for future investigation.

    Science.gov (United States)

    Phillips, Shaun M; Sproule, John; Turner, Anthony P

    2011-07-01

    There is a growing body of research on the influence of ingesting carbohydrate-electrolyte solutions immediately prior to and during prolonged intermittent, high-intensity exercise (team games exercise) designed to replicate field-based team games. This review presents the current body of knowledge in this area, and identifies avenues of further research. Almost all early work supported the ingestion of carbohydrate-electrolyte solutions during prolonged intermittent exercise, but was subject to methodological limitations. A key concern was the use of exercise protocols characterized by prolonged periods at the same exercise intensity, the lack of maximal- or high-intensity work components and long periods of seated recovery, which failed to replicate the activity pattern or physiological demand of team games exercise. The advent of protocols specifically designed to replicate the demands of field-based team games enabled a more externally valid assessment of the influence of carbohydrate ingestion during this form of exercise. Once again, the research overwhelmingly supports carbohydrate ingestion immediately prior to and during team games exercise for improving time to exhaustion during intermittent running. While the external validity of exhaustive exercise at fixed prescribed intensities as an assessment of exercise capacity during team games may appear questionable, these assessments should perhaps not be viewed as exhaustive exercise tests per se, but as indicators of the ability to maintain high-intensity exercise, which is a recognized marker of performance and fatigue during field-based team games. Possible mechanisms of exercise capacity enhancement include sparing of muscle glycogen, glycogen resynthesis during low-intensity exercise periods and attenuated effort perception during exercise. Most research fails to show improvements in sprint performance during team games exercise with carbohydrate ingestion, perhaps due to the lack of influence of

  4. Mitigation of commutation failures in LCC-HVDC systems based on superconducting fault current limiters

    Science.gov (United States)

    Lee, Jong-Geon; Khan, Umer Amir; Lee, Ho-Yun; Lim, Sung-Woo; Lee, Bang-Wook

    2016-11-01

    Commutation failure in line commutated converter based HVDC systems cause severe damages on the entire power grid system. For LCC-HVDC, thyristor valves are turned on by a firing signal but turn off control is governed by the external applied AC voltage from surrounding network. When the fault occurs in AC system, turn-off control of thyristor valves is unavailable due to the voltage collapse of point of common coupling (PCC), which causes the commutation failure in LCC-HVDC link. Due to the commutation failure, the power transfer interruption, dc voltage drop and severe voltage fluctuation in the AC system could be occurred. In a severe situation, it might cause the protection system to block the valves. In this paper, as a solution to prevent the voltage collapse on PCC and to limit the fault current, the application study of resistive superconducting fault current limiter (SFCL) on LCC-HVDC grid system was performed with mathematical and simulation analyses. The simulation model was designed by Matlab/Simulink considering Haenam-Jeju HVDC power grid in Korea which includes conventional AC system and onshore wind farm and resistive SFCL model. From the result, it was observed that the application of SFCL on LCC-HVDC system is an effective solution to mitigate the commutation failure. And then the process to determine optimum quench resistance of SFCL which enables the recovery of commutation failure was deeply investigated.

  5. Superconducting fault current limiter. Fifth quarterly technical progress report, August 8, 1978-November 7, 1979

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    Progress in the development of fault current limiters for superconducting power transmission systems is reported. The analysis and design of a magnetically switched resistive device and the experimental program were emphasized and reported. A transient heat transfer model was developed which indicates the parameters which are important in determining the thermal heating and recovery of the superconduting film. Designs for the switching coil and the S/C element were also carried out and are reported. A four-pole magnetic coil is recommended; this generates a magnetic field which is nearly perpendicular to spiral or helical S/C film geometrics. A spirally-designed, 3000 ohm limiter is shown to be able to fit within a .5 to 1m inner radius, .05 to .03 m wide, 1.3 to 3.9 m long annualr region. The experimental program has included work on materials development and on prepartion of the switching and thermal recovery experimental facility. The material development program has uncovered several serious short-comings of NbN as the S/C film material. Macroscopic holes and surface debris, and microscopic imperfections reduce the critical current density below the expected value and, in addition, cause nonuniform switching. Reasons for these effects are postulated, and a continuing, vigorous materials program is suggested in hopes of alleviating these problems. Virtually all of the experimental equipment had been installed, and so the magnetic switching and thermal recovery experiments can begin and progress during the next quarter. (LCL)

  6. What Could You Really Learn on Your Own?: Understanding the Epistemic Limitations of Knowledge Acquisition.

    Science.gov (United States)

    Lockhart, Kristi L; Goddu, Mariel K; Smith, Eric D; Keil, Frank C

    2016-01-01

    Three studies explored the abilities of 205 children (5-11 years) and 74 adults (18-72 years) to distinguish directly versus indirectly acquired information in a scenario where an individual grew up in isolation from human culture. Directly acquired information is knowledge acquired through firsthand experience. Indirectly acquired information is knowledge that requires input from others. All children distinguished directly from indirectly acquired knowledge (Studies 1-3), even when the indirectly acquired knowledge was highly familiar (Study 2). All children also distinguished difficult-to-acquire direct knowledge from simple-to-acquire direct knowledge (Study 3). The major developmental change was the increasing ability to completely rule out indirect knowledge as possible for an isolated individual to acquire. © 2015 The Authors. Child Development © 2015 Society for Research in Child Development, Inc.

  7. Superconducting fault current limiter. Fourth quarterly technical progress report, May 8-July 7, 1979

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    Up until now, this project has established performance objectives for the superconducting fault current limiter (SCFCL) in terms of the limitations of circuit breakers and strategies for locating the SCFCLs within the system. During this fourth quarter, the possibility has also been explored of using SCFCLs to protect specific machines, namely superconducting alternators and transformers. Unique characteristics and requirements of these machines are identified in section 2 of this report and the possible benefits to be gained by using SCFCLs are suggested. It is concluded that no further specific design work, either on the SCFCL or on the machines be done toward this goal until these superconducting devices have proved themselves further. The most promising SCFCL device is the resistive type of limiter (see the Second Quarterly Report for this project). The detailed analysis and design of this device have proceeded in the following aspects this quarter: transient circuit analysis; transient heat transfer analysis; switching field and film geometry; and shunt resistance and shunt capacitance.

  8. Bringing biofuels on the market. Options to increase EU biofuels volumes beyond the current blending limits

    Energy Technology Data Exchange (ETDEWEB)

    Kampman, B.; Van Grinsven, A.; Croezen, H. [CE Delft, Delft (Netherlands); Verbeek, R.; Van Mensch, P.; Patuleia, A. [TNO, Delft, (Netherlands)

    2013-07-15

    This handbook on biofuels provides a comprehensive overview of different types of biofuels, and the technical options that exist to market the biofuels volumes expected to be consumed in the EU Member States in 2020. The study concludes that by fully utilizing the current blending limits of biodiesel (FAME) in diesel (B7) and bioethanol in petrol (E10) up to 7.9% share of biofuels in the EU transport sector can be technically reached by 2020. Increasing use of advanced biofuels, particularly blending of fungible fuels into diesel (eg. HVO and BTL) and the use of higher ethanol blends in compatible vehicles (e.g. E20), can play an important role. Also, the increased use of biomethane (in particular bio-CNG) and higher blends of biodiesel (FAME) can contribute. However, it is essential for both governments and industry to decide within 1 or 2 years on the way ahead and take necessary actions covering both, the fuels and the vehicles, to ensure their effective and timely implementation. Even though a range of technical options exist, many of these require considerable time and effort to implement and reach their potential. Large scale implementation of the options beyond current blending limits requires new, targeted policy measures, in many cases complemented by new fuel and vehicle standards, adaptation of engines and fuel distribution, etc. Marketing policies for these vehicles, fuels and blends are also likely to become much more important than in the current situation. Each Member State may develop its own strategy tailored to its market and policy objectives, but the EU should play a crucial facilitating role in these developments.

  9. Early life determinants of physical activity and sedentary time: Current knowledge and future research

    Directory of Open Access Journals (Sweden)

    Guro Pauck Øglund

    2014-12-01

    Full Text Available Previous findings of the association between low birth weight and subsequent health outcomes have led to the “developmental origins of health and disease hypothesis”. Furthermore, modifiable and partly modifiable early life factors may also influence behaviors such as physical activity and sedentary behavior. The aim of the present review was to summarize the existing knowledge on early life determinants (birth weight, rapid infant weight gain, motor development and infant temperament of childhood physical activity and sedentary time, and suggest opportunities for future research based on the Mother and Child Cohort Study (MoBa. Inconsistent results have been observed when relating birth weight to later physical activity, likely explained by differences in methodology when assessing physical activity between studies. There is limited data on whether rapid weight gain in early life predicts later physical activity and few studies have examined the association between birth weight and infant weight gain with subsequent sedentary time. Motor development may be a predictor for childhood physical activity, however methodological limitations preclude firm conclusions. The association between motor development and sedentary time has rarely been examined. Conflicting results have been reported for the association between infant temperament and subsequent physical activity and sedentary time in toddlers. Finally, it is unknown whether physical activity modifies the association between birth weight, postnatal weight gain, and later health outcomes in youth. Additional research in well-characterized birth cohorts can be used to generate new knowledge on possible early life determinants of children’s and youth’s physical activity and sedentary time which may inform evidence-based public health interventions.

  10. Current State of Knowledge About Cancer in Lesbians, Gay, Bisexual, and Transgender (LGBT) People.

    Science.gov (United States)

    Margolies, Liz; Brown, Carlton G

    2018-02-01

    To review the current state of knowledge about cancer in lesbians, gay, bisexual, and transgender (LGBT) people by focusing on four major issues across the cancer continuum including: 1) lack of data collection on sexual orientation and gender identity; 2) need for a culturally competent workforce; 3) the need for a culturally competent health care system; and 4) creating LGBT tailored patient/client information and education. Published literature. Oncology nurses and health care providers can work to improve the care of LGBT patients with cancer by following suggestions in this article. Oncology nurses and other health care providers have many distinct occasions to improve overall cancer care for LGBT patients. Copyright © 2017 Elsevier Inc. All rights reserved.

  11. Current Knowledge and Practice of Pediatric Providers in Umbilical Cord Blood Banking.

    Science.gov (United States)

    Armstrong, Amy E; Fonstad, Rachel; Spellman, Stephen; Tullius, Zoe; Chaudhury, Sonali

    2018-02-01

    More than 35 000 umbilical cord blood (UCB) transplants have been performed worldwide, prompting the development of private and public banks to collect and store UCB cells. We hypothesized that pediatricians, who are uniquely poised to discuss UCB banking (UCBB) during prenatal or sibling visits, rarely do so. Through distribution of a 26-question electronic survey to general and subspecialty pediatric providers, we assessed baseline knowledge and conversations about UCBB. A total of 473 providers completed the survey; only 22% of physicians ever discussed UCBB with expectant parents. The majority responded that autologous UCB transplants were indicated in malignant (73%) and nonmalignant (61%) conditions; however, these are rare indications. Providers practicing >10 years were more likely to address UCBB ( P ≤ .001), whereas younger and female general pediatric providers were significantly less likely ( P < .001). Overall, pediatric providers rarely speak to families about UCBB, and we believe that they can be better informed to its current clinical utility.

  12. Bordetella holmesii infection: current knowledge and a vision for future research.

    Science.gov (United States)

    Pittet, Laure F; Posfay-Barbe, Klara M

    2015-08-01

    Bordetella holmesii is a recently recognized Gram-negative bacterium causing both pertussis-like respiratory symptoms and invasive infections, such as bacteremia, pneumonia, meningitis, arthritis, pericarditis and endocarditis. Few data are available on its epidemiological characteristics, mostly related to respiratory infections. However, these are frequently misdiagnosed as a Bordetella pertussis infection as most diagnostic tests routinely used are not species-specific, thus biasing the epidemiological studies of both strains, as well as the efficacy studies on pertussis vaccination. There is no accepted agreement on treatment and it remains unknown if antimicrobial prophylaxis is indicated in certain clinical settings. We review here the current knowledge on B. holmesii and the need for further research.

  13. Genetic Vulnerability as a Distal Risk Factor for Suicidal Behaviour: Historical Perspective and Current Knowledge.

    Science.gov (United States)

    Andriessen, Karl; Videtic-Paska, Alja

    2015-09-01

    Suicide is a multidimensional problem. Observations of family history of suicide suggest the existence of a genetic vulnerability to suicidal behaviour. Starting with a historical perspective, the article reviews current knowledge of a genetic vulnerability to suicidal behaviour, distinct from the genetic vulnerability to psychiatric disorders, focused on clinical and population-based studies, and findings from recent molecular genetics association studies. The review includes peer-reviewed research articles and review papers from the professional literature in English language, retrieved from PubMed/Medline and PsycINFO. The research literature confirms a existence of a genetic vulnerability to suicidal behaviour. Even though the results of individual studies are difficult to compare, genetic influences could explain up to half of the variance of the occurrence of suicide. Genetic vulnerability could be a distal risk factor for suicide, which helps us to understand the occurrence of suicide among vulnerable people. Ethical implications of such vulnerability are highlighted.

  14. Cardiomyopathy syndrome in Atlantic salmon Salmo salar L.: A review of the current state of knowledge.

    Science.gov (United States)

    Garseth, Å H; Fritsvold, C; Svendsen, J C; Bang Jensen, B; Mikalsen, A B

    2017-10-24

    Cardiomyopathy syndrome (CMS) is a severe cardiac disease affecting Atlantic salmon Salmo salar L. The disease was first recognized in farmed Atlantic salmon in Norway in 1985 and subsequently in farmed salmon in the Faroe Islands, Scotland and Ireland. CMS has also been described in wild Atlantic salmon in Norway. The demonstration of CMS as a transmissible disease in 2009, and the subsequent detection and initial characterization of piscine myocarditis virus (PMCV) in 2010 and 2011 were significant discoveries that gave new impetus to the CMS research. In Norway, CMS usually causes mortality in large salmon in ongrowing and broodfish farms, resulting in reduced fish welfare, significant management-related challenges and substantial economic losses. The disease thus has a significant impact on the Atlantic salmon farming industry. There is a need to gain further basic knowledge about the virus, the disease and its epidemiology, but also applied knowledge from the industry to enable the generation and implementation of effective prevention and control measures. This review summarizes the currently available, scientific information on CMS and PMCV with special focus on epidemiology and factors influencing the development of CMS. © 2017 The Authors. Journal of Fish Diseases Published by John Wiley & Sons Ltd.

  15. The Role of Soil Microorganisms in Plant Mineral Nutrition—Current Knowledge and Future Directions

    Science.gov (United States)

    Jacoby, Richard; Peukert, Manuela; Succurro, Antonella; Koprivova, Anna; Kopriva, Stanislav

    2017-01-01

    In their natural environment, plants are part of a rich ecosystem including numerous and diverse microorganisms in the soil. It has been long recognized that some of these microbes, such as mycorrhizal fungi or nitrogen fixing symbiotic bacteria, play important roles in plant performance by improving mineral nutrition. However, the full range of microbes associated with plants and their potential to replace synthetic agricultural inputs has only recently started to be uncovered. In the last few years, a great progress has been made in the knowledge on composition of rhizospheric microbiomes and their dynamics. There is clear evidence that plants shape microbiome structures, most probably by root exudates, and also that bacteria have developed various adaptations to thrive in the rhizospheric niche. The mechanisms of these interactions and the processes driving the alterations in microbiomes are, however, largely unknown. In this review, we focus on the interaction of plants and root associated bacteria enhancing plant mineral nutrition, summarizing the current knowledge in several research fields that can converge to improve our understanding of the molecular mechanisms underpinning this phenomenon. PMID:28974956

  16. The Role of Soil Microorganisms in Plant Mineral Nutrition—Current Knowledge and Future Directions

    Directory of Open Access Journals (Sweden)

    Richard Jacoby

    2017-09-01

    Full Text Available In their natural environment, plants are part of a rich ecosystem including numerous and diverse microorganisms in the soil. It has been long recognized that some of these microbes, such as mycorrhizal fungi or nitrogen fixing symbiotic bacteria, play important roles in plant performance by improving mineral nutrition. However, the full range of microbes associated with plants and their potential to replace synthetic agricultural inputs has only recently started to be uncovered. In the last few years, a great progress has been made in the knowledge on composition of rhizospheric microbiomes and their dynamics. There is clear evidence that plants shape microbiome structures, most probably by root exudates, and also that bacteria have developed various adaptations to thrive in the rhizospheric niche. The mechanisms of these interactions and the processes driving the alterations in microbiomes are, however, largely unknown. In this review, we focus on the interaction of plants and root associated bacteria enhancing plant mineral nutrition, summarizing the current knowledge in several research fields that can converge to improve our understanding of the molecular mechanisms underpinning this phenomenon.

  17. A review on current knowledge and future prospects of organohalogen contaminants (OHCs) in Asian birds

    Energy Technology Data Exchange (ETDEWEB)

    Abbasi, Naeem Akhtar [Environmental Biology and Ecotoxicology Laboratory, Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Malik, Riffat Naseem, E-mail: r_n_malik2000@yahoo.co.uk [Environmental Biology and Ecotoxicology Laboratory, Department of Environmental Sciences, Faculty of Biological Sciences, Quaid-i-Azam University, Islamabad 45320 (Pakistan); Frantz, Adrien [Sorbonne Universités, UPMC Univ Paris 06, UPEC, Paris 7, CNRS, INRA, IRD, Institut d' Ecologie et des Sciences de l' Environnement de Paris, F-75005, Paris (France); Jaspers, Veerle Leontina Bernard [Environmental Toxicology, Department of Biology, Norwegian University of Science and Technology (NTNU), Trondheim (Norway)

    2016-01-15

    The release of harmful chemicals in the Asian environment has recently increased dramatically due to rising industrial and agricultural activities. About 60% of the global human population is currently living on the Asian continent and may thus be exposed to a large range of different chemicals. Different classes of organohalogen chemicals have indeed been reported in various environmental compartments from Asia including humans and wildlife, but this issue has received less attention in birds. In this article, we reviewed the available literature on levels of legacy persistent organic pollutants (POPs) and various flame retardants (FRs) in Asian avifauna to analyze the existing pool of knowledge as well as to identify the gaps that should be addressed in future research. Furthermore, we discussed the variation in levels of organohalogens based on differences in regions, trophic level, dietary sources and migratory behaviors of species including distribution patterns in different tissues of birds. Although the mass of published literature is very low and even absent in many important regions of Asia, we deduced from the reported studies that levels of almost all classes of organohalogens (OHCs) including FRs were highest in East Asian countries such as Japan, China and South Korea, except for HCHs that were found at maximum levels in birds of South India. Concentrations (ng/g LW) of different OHCs in Asian birds ranged between < LOD (limit of detection) to 14,000,000 for polychlorinated biphenyls (PCBs), < LOD to 790,000 for dichlorodiphenyltrichloroethane (DDTs), < LOD to 12,000 for hexachlorobenzene (HCB), < LOD to 29,000 for hexachlorocyclohexanes (HCHs), < LOD to 47,000 for chlordanes (CHLs) and < LOD to 4600 for total cyclodienes. Further, ranges (ng/g LW) of 1.1 to 150,000 for Co-PCBs; < LOD to 27 for polychlorinated dibenzo-p-dioxins (PCDDs); < LOD to 45 for polychlorinated dibenzofurans (PCDFs) and 0.02 to 73 for PCDD/DFs have been reported in Asian aves

  18. Analysis of a flux-coupling type superconductor fault current limiter with pancake coils

    Science.gov (United States)

    Liu, Shizhuo; Xia, Dong; Zhang, Zhifeng; Qiu, Qingquan; Zhang, Guomin

    2017-10-01

    The characteristics of a flux-coupling type superconductor fault current limiter (SFCL) with pancake coils are investigated in this paper. The conventional double-wound non-inductive pancake coil used in AC power systems has an inevitable defect in Voltage Sourced Converter Based High Voltage DC (VSC-HVDC) power systems. Due to its special structure, flashover would occur easily during the fault in high voltage environment. Considering the shortcomings of conventional resistive SFCLs with non-inductive coils, a novel flux-coupling type SFCL with pancake coils is carried out. The module connections of pancake coils are performed. The electromagnetic field and force analysis of the module are contrasted under different parameters. To ensure proper operation of the module, the impedance of the module under representative operating conditions is calculated. Finally, the feasibility of the flux-coupling type SFCL in VSC-HVDC power systems is discussed.

  19. Development and Testing of a Transmission Voltage SuperLimiter™ Fault Current Limiter

    Energy Technology Data Exchange (ETDEWEB)

    Romanosky, Walter [American Superconductor Corporation, Devens, MA (United States)

    2012-09-01

    This report summarizes work by American Superconductor (AMSC), Los Alamos National Laboratory (LANL), Nexans, Siemens and Southern California Edison on a 138kV resistive type high temperature superconductor (HTS) fault current limiter (FCL) under a cooperative agreement with the U.S. Department of Energy (DOE). Phase 1A encompassed core technology development and system design and was previously reported (see summary that follows in Section 1.1 of the Introduction). This report primarily discusses work performed during Phase 1B, and addresses the fabrication and test of a single-phase prototype FCL. The results are presented along with a discussion of requirements/specifications and lessons learned to aid future development and product commercialization.

  20. Advantages and Limitations of Current Imaging Techniques for Characterizing Liposome Morphology

    Directory of Open Access Journals (Sweden)

    Annie-Louise Robson

    2018-02-01

    Full Text Available There are currently a number of imaging techniques available for evaluating the morphology of liposomes and other nanoparticles, with each having its own advantages and disadvantages that should be considered when interpreting data. Controlling and validating the morphology of nanoparticles is of key importance for the effective clinical translation of liposomal formulations. There are a number of physical characteristics of liposomes that determine their in vivo behavior, including size, surface characteristics, lamellarity, and homogeneity. Despite the great importance of the morphology of nanoparticles, it is generally not well-characterized and is difficult to control. Appropriate imaging techniques provide important details regarding the morphological characteristics of nanoparticles, and should be used in conjunction with other methods to assess physicochemical parameters. In this review, we will discuss the advantages and limitations of available imaging techniques used to evaluate liposomal formulations.

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

    Science.gov (United States)

    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.

  2. Developing a Knowledge Management Framework to Assist With Current USMC Information Management Practices

    Science.gov (United States)

    2010-09-01

    November 13). Air Force Center of Excellence for Knowledge Mangement Briefing. Washington, D.C. Alavi, M., & Leidner, D. E. (2001). Review: Knowledge...Strategic Management Journal , 473-496. Holsapple, C. W., & Jones, K. (2006). Knowledge Mangement Strategy Formation. Managerial Aspects of Knowledge... Mangement , 419-428. 70 Hoss, R., & Schlussel, A. (2009). How Do You Measure the Knowledge Management (KM) Maturity of Your Organization? Metrics

  3. Caroli's Disease: Current Knowledge of Its Biliary Pathogenesis Obtained from an Orthologous Rat Model

    Directory of Open Access Journals (Sweden)

    Yasunori Sato

    2012-01-01

    Full Text Available Caroli's disease belongs to a group of hepatic fibropolycystic diseases and is a hepatic manifestation of autosomal recessive polycystic kidney disease (ARPKD. It is a congenital disorder characterized by segmental saccular dilatations of the large intrahepatic bile duct and is frequently associated with congenital hepatic fibrosis (CHF. The most viable theory explaining its pathogenesis suggests that it is related to ductal plate malformation. The development of the polycystic kidney (PCK rat, an orthologous rodent model of Caroli's disease with CHF as well as ARPKD, has allowed the molecular pathogenesis of the disease and the therapeutic options for its treatment to be examined. The relevance of the findings of studies using PCK rats and/or the cholangiocyte cell line derived from them to the pathogenesis of human Caroli's disease is currently being analyzed. Fibrocystin/polyductin, the gene product responsible for ARPKD, is normally localized to primary cilia, and defects in the fibrocystin from primary cilia are observed in PCK cholangiocytes. Ciliopathies involving PCK cholangiocytes (cholangiociliopathies appear to be associated with decreased intracellular calcium levels and increased cAMP concentrations, causing cholangiocyte hyperproliferation, abnormal cell matrix interactions, and altered fluid secretion, which ultimately result in bile duct dilatation. This article reviews the current knowledge about the pathogenesis of Caroli's disease with CHF, particularly focusing on studies of the mechanism responsible for the biliary dysgenesis observed in PCK rats.

  4. Beer Polyphenols and Menopause: Effects and Mechanisms—A Review of Current Knowledge

    Directory of Open Access Journals (Sweden)

    Berner Andrée Sandoval-Ramírez

    2017-01-01

    Full Text Available Beer is one of the most frequently consumed fermented beverages in the world, and it has been part of the human diet for thousands of years. Scientific evidence obtained from the development of new techniques of food analysis over the last two decades suggests that polyphenol intake derived from moderate beer consumption may play a positive role in different health outcomes including osteoporosis and cardiovascular risk and the relief of vasomotor symptoms, which are commonly experienced during menopause and are an important reason why women seek medical care during this period; here, we review the current knowledge regarding moderate beer consumption and its possible effects on menopausal symptoms. The effect of polyphenol intake on vasomotor symptoms in menopause may be driven by the direct interaction of the phenolic compounds present in beer, such as 8-prenylnaringenin, 6-prenylnaringenin, and isoxanthohumol, with intracellular estrogen receptors that leads to the modulation of gene expression, increase in sex hormone plasma concentrations, and thus modulation of physiological hormone imbalance in menopausal women. Since traditional hormone replacement therapies increase health risks, alternative, safer treatment options are needed to alleviate menopausal symptoms in women. The present work aims to review the current data on this subject.

  5. Beer Polyphenols and Menopause: Effects and Mechanisms—A Review of Current Knowledge

    Science.gov (United States)

    Sandoval-Ramírez, Berner Andrée; M. Lamuela-Raventós, Rosa; Estruch, Ramon; Sasot, Gemma; Doménech, Monica

    2017-01-01

    Beer is one of the most frequently consumed fermented beverages in the world, and it has been part of the human diet for thousands of years. Scientific evidence obtained from the development of new techniques of food analysis over the last two decades suggests that polyphenol intake derived from moderate beer consumption may play a positive role in different health outcomes including osteoporosis and cardiovascular risk and the relief of vasomotor symptoms, which are commonly experienced during menopause and are an important reason why women seek medical care during this period; here, we review the current knowledge regarding moderate beer consumption and its possible effects on menopausal symptoms. The effect of polyphenol intake on vasomotor symptoms in menopause may be driven by the direct interaction of the phenolic compounds present in beer, such as 8-prenylnaringenin, 6-prenylnaringenin, and isoxanthohumol, with intracellular estrogen receptors that leads to the modulation of gene expression, increase in sex hormone plasma concentrations, and thus modulation of physiological hormone imbalance in menopausal women. Since traditional hormone replacement therapies increase health risks, alternative, safer treatment options are needed to alleviate menopausal symptoms in women. The present work aims to review the current data on this subject. PMID:28904736

  6. Caroli's Disease: Current Knowledge of Its Biliary Pathogenesis Obtained from an Orthologous Rat Model.

    Science.gov (United States)

    Sato, Yasunori; Ren, Xiang Shan; Nakanuma, Yasuni

    2012-01-01

    Caroli's disease belongs to a group of hepatic fibropolycystic diseases and is a hepatic manifestation of autosomal recessive polycystic kidney disease (ARPKD). It is a congenital disorder characterized by segmental saccular dilatations of the large intrahepatic bile duct and is frequently associated with congenital hepatic fibrosis (CHF). The most viable theory explaining its pathogenesis suggests that it is related to ductal plate malformation. The development of the polycystic kidney (PCK) rat, an orthologous rodent model of Caroli's disease with CHF as well as ARPKD, has allowed the molecular pathogenesis of the disease and the therapeutic options for its treatment to be examined. The relevance of the findings of studies using PCK rats and/or the cholangiocyte cell line derived from them to the pathogenesis of human Caroli's disease is currently being analyzed. Fibrocystin/polyductin, the gene product responsible for ARPKD, is normally localized to primary cilia, and defects in the fibrocystin from primary cilia are observed in PCK cholangiocytes. Ciliopathies involving PCK cholangiocytes (cholangiociliopathies) appear to be associated with decreased intracellular calcium levels and increased cAMP concentrations, causing cholangiocyte hyperproliferation, abnormal cell matrix interactions, and altered fluid secretion, which ultimately result in bile duct dilatation. This article reviews the current knowledge about the pathogenesis of Caroli's disease with CHF, particularly focusing on studies of the mechanism responsible for the biliary dysgenesis observed in PCK rats.

  7. Effective field theory of dissipative fluids (II): classical limit, dynamical KMS symmetry and entropy current

    Science.gov (United States)

    Glorioso, Paolo; Crossley, Michael; Liu, Hong

    2017-09-01

    In this paper we further develop the fluctuating hydrodynamics proposed in [1] in a number of ways. We first work out in detail the classical limit of the hydrodynamical action, which exhibits many simplifications. In particular, this enables a transparent formulation of the action in physical spacetime in the presence of arbitrary external fields. It also helps to clarify issues related to field redefinitions and frame choices. We then propose that the action is invariant under a Z 2 symmetry to which we refer as the dynamical KMS symmetry. The dynamical KMS symmetry is physically equivalent to the previously proposed local KMS condition in the classical limit, but is more convenient to implement and more general. It is applicable to any states in local equilibrium rather than just thermal density matrix perturbed by external background fields. Finally we elaborate the formulation for a conformal fluid, which contains some new features, and work out the explicit form of the entropy current to second order in derivatives for a neutral conformal fluid.

  8. Endoscopic diagnosis of extrahepatic bile duct carcinoma: Advances and current limitations

    Science.gov (United States)

    Tamada, Kiichi; Ushio, Jun; Sugano, Kentaro

    2011-01-01

    The accurate diagnosis of extrahepatic bile duct carcinoma is difficult, even now. When ultrasonography (US) shows dilatation of the bile duct, magnetic resonance cholangiopancreatography followed by endoscopic US (EUS) is the next step. When US or EUS shows localized bile duct wall thickening, endoscopic retrograde cholangiopancreatography should be conducted with intraductal US (IDUS) and forceps biopsy. Fluorescence in situ hybridization increases the sensitivity of brush cytology with similar specificity. In patients with papillary type bile duct carcinoma, three biopsies are sufficient. In patients with nodular or infiltrating-type bile duct carcinoma, multiple biopsies are warranted, and IDUS can compensate for the limitations of biopsies. In preoperative staging, the combination of dynamic multi-detector low computed tomography (MDCT) and IDUS is useful for evaluating vascular invasion and cancer depth infiltration. However, assessment of lymph nodes metastases is difficult. In resectable cases, assessment of longitudinal cancer spread is important. The combination of IDUS and MDCT is useful for revealing submucosal cancer extension, which is common in hilar cholangiocarcinoma. To estimate the mucosal extension, which is common in extrahepatic bile duct carcinoma, the combination of IDUS and cholangioscopy is required. The utility of current peroral cholangioscopy is limited by the maneuverability of the “baby scope”. A new baby scope (10 Fr), called “SpyGlass” has potential, if the image quality can be improved. Since extrahepatic bile duct carcinoma is common in the Far East, many researchers in Japan and Korea contributed these studies, especially, in the evaluation of longitudinal cancer extension. PMID:21611097

  9. Assessing Exposure and Health Consequences of Chemicals in Drinking Water: Current State of Knowledge and Research Needs

    Science.gov (United States)

    Kogevinas, Manolis; Cordier, Sylvaine; Templeton, Michael R.; Vermeulen, Roel; Nuckols, John R.; Nieuwenhuijsen, Mark J.; Levallois, Patrick

    2014-01-01

    Background: Safe drinking water is essential for well-being. Although microbiological contamination remains the largest cause of water-related morbidity and mortality globally, chemicals in water supplies may also cause disease, and evidence of the human health consequences is limited or lacking for many of them. Objectives: We aimed to summarize the state of knowledge, identify gaps in understanding, and provide recommendations for epidemiological research relating to chemicals occurring in drinking water. Discussion: Assessing exposure and the health consequences of chemicals in drinking water is challenging. Exposures are typically at low concentrations, measurements in water are frequently insufficient, chemicals are present in mixtures, exposure periods are usually long, multiple exposure routes may be involved, and valid biomarkers reflecting the relevant exposure period are scarce. In addition, the magnitude of the relative risks tends to be small. Conclusions: Research should include well-designed epidemiological studies covering regions with contrasting contaminant levels and sufficient sample size; comprehensive evaluation of contaminant occurrence in combination with bioassays integrating the effect of complex mixtures; sufficient numbers of measurements in water to evaluate geographical and temporal variability; detailed information on personal habits resulting in exposure (e.g., ingestion, showering, swimming, diet); collection of biological samples to measure relevant biomarkers; and advanced statistical models to estimate exposure and relative risks, considering methods to address measurement error. Last, the incorporation of molecular markers of early biological effects and genetic susceptibility is essential to understand the mechanisms of action. There is a particular knowledge gap and need to evaluate human exposure and the risks of a wide range of emerging contaminants. Citation: Villanueva CM, Kogevinas M, Cordier S, Templeton MR, Vermeulen R

  10. Scoring of coronary artery calcium scans: history, assumptions, current limitations, and future directions.

    Science.gov (United States)

    Alluri, Krishna; Joshi, Parag H; Henry, Travis S; Blumenthal, Roger S; Nasir, Khurram; Blaha, Michael J

    2015-03-01

    Coronary artery calcium (CAC) scanning is a reliable, noninvasive technique for estimating overall coronary plaque burden and for identifying risk for future cardiac events. Arthur Agatston and Warren Janowitz published the first technique for scoring CAC scans in 1990. Given the lack of available data correlating CAC with burden of coronary atherosclerosis at that time, their scoring algorithm was remarkable, but somewhat arbitrary. Since then, a few other scoring techniques have been proposed for the measurement of CAC including the Volume score and Mass score. Yet despite new data, little in this field has changed in the last 15 years. The main focus of our paper is to review the implications of the current approach to scoring CAC scans in terms of correlation with the central disease - coronary atherosclerosis. We first discuss the methodology of each available scoring system, describing how each of these scores make important indirect assumptions in the way they account (or do not account) for calcium density, location of calcium, spatial distribution of calcium, and microcalcification/emerging calcium that might limit their predictive power. These assumptions require further study in well-designed, large event-driven studies. In general, all of these scores are adequate and are highly correlated with each other. Despite its age, the Agatston score remains the most extensively studied and widely accepted technique in both the clinical and research settings. After discussing CAC scoring in the era of contrast enhanced coronary CT angiography, we discuss suggested potential modifications to current CAC scanning protocols with respect to tube voltage, tube current, and slice thickness which may further improve the value of CAC scoring. We close with a focused discussion of the most important future directions in the field of CAC scoring. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  11. Demographic and traditional knowledge perspectives on the current status of Canadian polar bear subpopulations.

    Science.gov (United States)

    York, Jordan; Dowsley, Martha; Cornwell, Adam; Kuc, Miroslaw; Taylor, Mitchell

    2016-05-01

    Subpopulation growth rates and the probability of decline at current harvest levels were determined for 13 subpopulations of polar bears (Ursus maritimus) that are within or shared with Canada based on mark-recapture estimates of population numbers and vital rates, and harvest statistics using population viability analyses (PVA). Aboriginal traditional ecological knowledge (TEK) on subpopulation trend agreed with the seven stable/increasing results and one of the declining results, but disagreed with PVA status of five other declining subpopulations. The decline in the Baffin Bay subpopulation appeared to be due to over-reporting of harvested numbers from outside Canada. The remaining four disputed subpopulations (Southern Beaufort Sea, Northern Beaufort Sea, Southern Hudson Bay, and Western Hudson Bay) were all incompletely mark-recapture (M-R) sampled, which may have biased their survival and subpopulation estimates. Three of the four incompletely sampled subpopulations were PVA identified as nonviable (i.e., declining even with zero harvest mortality). TEK disagreement was nonrandom with respect to M-R sampling protocols. Cluster analysis also grouped subpopulations with ambiguous demographic and harvest rate estimates separately from those with apparently reliable demographic estimates based on PVA probability of decline and unharvested subpopulation growth rate criteria. We suggest that the correspondence between TEK and scientific results can be used to improve the reliability of information on natural systems and thus improve resource management. Considering both TEK and scientific information, we suggest that the current status of Canadian polar bear subpopulations in 2013 was 12 stable/increasing and one declining (Kane Basin). We do not find support for the perspective that polar bears within or shared with Canada are currently in any sort of climate crisis. We suggest that monitoring the impacts of climate change (including sea ice decline) on polar bear

  12. Hydrogeology and management of freshwater lenses on atoll islands: Review of current knowledge and research needs

    Science.gov (United States)

    Werner, Adrian D.; Sharp, Hannah K.; Galvis, Sandra C.; Post, Vincent E. A.; Sinclair, Peter

    2017-08-01

    On atoll islands, fresh groundwater occurs as a buoyant lens-shaped body surrounded by saltwater derived from the sea, forming the main freshwater source for many island communities. A review of the state of knowledge of atoll island groundwater is overdue given their susceptibility to adverse impacts, and the task to address water access and sanitation issues within the United Nations' Sustainable Development Goals framework before the year 2030. In this article, we review available literature to summarise the key processes, investigation techniques and management approaches of atoll island groundwater systems. Over fifty years of investigation has led to important advancements in the understanding of atoll hydrogeology, but a paucity of hydrogeological data persists on all but a small number of atoll islands. We find that the combined effects of buoyancy forces, complex geology, tides, episodic ocean events, strong climatic variability and human impacts create highly dynamic fresh groundwater lenses. Methods used to quantify freshwater availability range from simple empirical relationships to three-dimensional density-dependent models. Generic atoll island numerical models have proven popular in trying to unravel the individual factors controlling fresh groundwater lens behaviour. Major challenges face the inhabitants and custodians of atoll island aquifers, with rising anthropogenic stresses compounded by the threats of climate variability and change, sea-level rise, and some atolls already extracting freshwater at or above sustainability limits. We find that the study of atoll groundwater systems remains a critical area for further research effort to address persistent knowledge gaps, which lead to high uncertainties in water security issues for both island residents and surrounding environs.

  13. HIV/AIDS Knowledge, Self-Efficacy for Limiting Sexual Risk Behavior and Parental Monitoring.

    Science.gov (United States)

    Mahat, Ganga; Scoloveno, Mary Ann; Scoloveno, Robert

    2016-01-01

    The purpose of this study was to explore HIV/AIDS knowledge, self-efficacy for sexual risk behaviors, and parental monitoring in a sample of 140 7th and 9th grade adolescents studying in an urban high school in the United States. Further, the study examined differences in HIV/AIDS knowledge, self-efficacy and parental monitoring by grade and gender. This study also investigated the effectiveness of an HIV/AIDS peer education program, Teens for AIDS Prevention (TAP), on improving adolescents' HIV/AIDS knowledge. A quasi-experimental design was used to examine effects of the peer education program (TAP) on adolescents' HIV/AIDS knowledge. Pearson-product-moment correlation coefficients were calculated to examine the relationships among the variables. Independent t-tests were used to compare adolescents' HIV/AIDS knowledge, self-efficacy, and parental monitoring scores by grade and gender. Paired t-tests were used to determine differences in pre-intervention and post-intervention HIV/AIDS knowledge. The results showed that HIV/AIDS knowledge improved significantly in both 7th and 9th grade students after the intervention. HIV/AIDS knowledge was associated with self-efficacy; however it was not associated with parental monitoring. There were no significant differences in HIV/AIDS knowledge and self-efficacy by gender. However, there was a significant difference in parental monitoring by gender. Pediatric nurses are well-positioned to develop and implement evidence-based programs for adolescents. It is essential that pediatric nurses, in conjunction with other professionals and parent groups, take the initiative in implementing peer education programs in schools and community centers to promote healthy behaviors among adolescents. Copyright © 2016 Elsevier Inc. All rights reserved.

  14. Root System Architecture and Abiotic Stress Tolerance: Current Knowledge in Root and Tuber Crops

    Directory of Open Access Journals (Sweden)

    M. Awais Khan

    2016-11-01

    Full Text Available The challenge to produce more food for a rising global population on diminishing agricultural land is complicated by the effects of climate change on agricultural productivity. Although great progress has been made in crop improvement, so far most efforts have targeted above-ground traits. Roots are essential for plant adaptation and productivity, but are less studied due to the difficulty of observing them during the plant life cycle. Root system architecture, made up of structural features like root length, spread, number, and length of lateral roots, among others, exhibits great plasticity in response to environmental changes, and could be critical to developing crops with more efficient roots. Much of the research on root traits has thus far focused on the most common cereal crops and model plants. As cereal yields have reached their yield potential in some regions, understanding their root system may help overcome these plateaus. However, root and tuber crops such as potato, sweetpotato, cassava, and yam may hold more potential for providing food security in the future, and knowledge of their root system additionally focuses directly on the edible portion. Root-trait modeling for multiple stress scenarios, together with high-throughput phenotyping and genotyping techniques, robust databases, and data analytical pipelines, may provide a valuable base for a truly inclusive ‘green revolution’. In the current review, we discuss root system architecture with special reference to root and tuber crops, and how knowledge on genetics of root system architecture can be manipulated to improve their tolerance to abiotic stresses.

  15. Assessment of Global Incidence and Mortality of Hospital-treated Sepsis. Current Estimates and Limitations.

    Science.gov (United States)

    Fleischmann, Carolin; Scherag, André; Adhikari, Neill K J; Hartog, Christiane S; Tsaganos, Thomas; Schlattmann, Peter; Angus, Derek C; Reinhart, Konrad

    2016-02-01

    Reducing the global burden of sepsis, a recognized global health challenge, requires comprehensive data on the incidence and mortality on a global scale. To estimate the worldwide incidence and mortality of sepsis and identify knowledge gaps based on available evidence from observational studies. We systematically searched 15 international citation databases for population-level estimates of sepsis incidence rates and fatality in adult populations using consensus criteria and published in the last 36 years. The search yielded 1,553 reports from 1979 to 2015, of which 45 met our criteria. A total of 27 studies from seven high-income countries provided data for metaanalysis. For these countries, the population incidence rate was 288 (95% confidence interval [CI], 215-386; τ = 0.55) for hospital-treated sepsis cases and 148 (95% CI, 98-226; τ = 0.99) for hospital-treated severe sepsis cases per 100,000 person-years. Restricted to the last decade, the incidence rate was 437 (95% CI, 334-571; τ = 0.38) for sepsis and 270 (95% CI, 176-412; τ = 0.60) for severe sepsis cases per 100,000 person-years. Hospital mortality was 17% for sepsis and 26% for severe sepsis during this period. There were no population-level sepsis incidence estimates from lower-income countries, which limits the prediction of global cases and deaths. However, a tentative extrapolation from high-income country data suggests global estimates of 31.5 million sepsis and 19.4 million severe sepsis cases, with potentially 5.3 million deaths annually. Population-level epidemiologic data for sepsis are scarce and nonexistent for low- and middle-income countries. Our analyses underline the urgent need to implement global strategies to measure sepsis morbidity and mortality, particularly in low- and middle-income countries.

  16. Qualitative Contrast between Knowledge-Limited Mixed-State and Variable-Resources Models of Visual Change Detection

    Science.gov (United States)

    Nosofsky, Robert M.; Donkin, Chris

    2016-01-01

    We report an experiment designed to provide a qualitative contrast between knowledge-limited versions of mixed-state and variable-resources (VR) models of visual change detection. The key data pattern is that observers often respond "same" on big-change trials, while simultaneously being able to discriminate between same and small-change…

  17. Biological variation in musculoskeletal injuries: current knowledge, future research and practical implications.

    Science.gov (United States)

    Collins, Malcolm; September, Alison V; Posthumus, Michael

    2015-12-01

    Evidence from familial and genetic association studies have reported that DNA sequence variants play an important role, together with non-genetic factors, in the aetiology of both exercise-associated and occupational-associated acute and chronic musculoskeletal soft tissue injuries. The associated variants, which have been identified to date, may contribute to the interindividual variation in the structure and, by implication, mechanical properties of the collagen fibril and surrounding matrix within musculoskeletal soft tissues, as well as their response to mechanical loading and other stimuli. Future work should focus on the establishment of multidisciplinary international consortia for the identification of biologically relevant variants involved in modulating injury risk. These consortia will improve the limitations of the published hypothesis-driven genetic association studies, since they will allow resources to be pooled in recruiting large well-characterised cohorts required for whole-genome screening. Finally, clinicians and coaches need to be aware that many direct-to-consumer companies are currently marketing genetic tests directly to athletes without it being requested by an appropriately qualified healthcare professional, and without interpretation alongside other clinical indicators or lifestyle factors. These specific genetic tests are premature and are not necessarily required to evaluate susceptibility to musculoskeletal soft tissue injury. Current practice should rather consider susceptibility through known risk factors such as a positive family history of a specific injury, a history of other tendon and/or ligament injuries and participation in activities associated with the specific musculoskeletal injuries. Potential susceptible athletes may then be individually managed to reduce their risk profile. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  18. Q Fever: Current State of Knowledge and Perspectives of Research of a Neglected Zoonosis

    Directory of Open Access Journals (Sweden)

    Sarah Rebecca Porter

    2011-01-01

    Full Text Available Q fever is an ubiquitous zoonosis caused by an resistant intracellular bacterium, Coxiella burnetii. In certain areas, Q fever can be a severe public health problem, and awareness of the disease must be promoted worldwide. Nevertheless, knowledge of Coxiella burnetii remains limited to this day. Its resistant (intracellular and environmental and infectious properties have been poorly investigated. Further understanding of the interactions between the infected host and the bacteria is necessary. Domestic ruminants are considered as the main reservoir of bacteria. Infected animals shed highly infectious organisms in milk, feces, urine, vaginal mucus, and, very importantly, birth products. Inhalation is the main route of infection. Frequently asymptomatic in humans and animals, Q fever can cause acute or chronic infections. Financial consequences of infection can be dramatic at herd level. Vaccination with inactive whole-cell bacteria has been performed and proved effective in humans and animals. However, inactive whole-cell vaccines present several defects. Recombinant vaccines have been developed in experimental conditions and have great potential for the future. Q fever is a challenging disease for scientists as significant further investigations are necessary. Great research opportunities are available to reach a better understanding and thus a better prevention and control of the infection.

  19. Axial p–n junction and space charge limited current in single GaN nanowire

    Science.gov (United States)

    Fang, Zhihua; Donatini, Fabrice; Daudin, Bruno; Pernot, Julien

    2018-01-01

    The electrical characterizations of individual basic GaN nanostructures, such as axial nanowire (NW) p–n junctions, are becoming indispensable and crucial for the fully controlled realization of GaN NW based devices. In this study, electron beam induced current (EBIC) measurements were performed on two single axial GaN p–n junction NWs grown by plasma-assisted molecular beam epitaxy. I–V characteristics revealed that both ohmic and space charge limited current (SCLC) regimes occur in GaN p–n junction NW. Thanks to an improved contact process, both the electric field induced by the p–n junction and the SCLC in the p-part of GaN NW were disclosed and delineated by EBIC signals under different biases. Analyzing the EBIC profiles in the vicinity of the p–n junction under 0 V and reverse bias, we deduced a depletion width in the range of 116–125 nm. Following our previous work, the acceptor N a doping level was estimated to be 2–3 × 1017 at cm‑3 assuming a donor level N d of 2–3 × 1018 at cm‑3. The hole diffusion length in n-GaN was determined to be 75 nm for NW #1 and 43 nm for NW #2, demonstrating a low surface recombination velocity at the m-plane facet of n-GaN NW. Under forward bias, EBIC imaging visualized the electric field induced by the SCLC close to p-side contact, in agreement with unusual SCLC previously reported in GaN NWs.

  20. Concussion As a Multi-Scale Complex System: An Interdisciplinary Synthesis of Current Knowledge

    Science.gov (United States)

    Kenzie, Erin S.; Parks, Elle L.; Bigler, Erin D.; Lim, Miranda M.; Chesnutt, James C.; Wakeland, Wayne

    2017-01-01

    Traumatic brain injury (TBI) has been called “the most complicated disease of the most complex organ of the body” and is an increasingly high-profile public health issue. Many patients report long-term impairments following even “mild” injuries, but reliable criteria for diagnosis and prognosis are lacking. Every clinical trial for TBI treatment to date has failed to demonstrate reliable and safe improvement in outcomes, and the existing body of literature is insufficient to support the creation of a new classification system. Concussion, or mild TBI, is a highly heterogeneous phenomenon, and numerous factors interact dynamically to influence an individual’s recovery trajectory. Many of the obstacles faced in research and clinical practice related to TBI and concussion, including observed heterogeneity, arguably stem from the complexity of the condition itself. To improve understanding of this complexity, we review the current state of research through the lens provided by the interdisciplinary field of systems science, which has been increasingly applied to biomedical issues. The review was conducted iteratively, through multiple phases of literature review, expert interviews, and systems diagramming and represents the first phase in an effort to develop systems models of concussion. The primary focus of this work was to examine concepts and ways of thinking about concussion that currently impede research design and block advancements in care of TBI. Results are presented in the form of a multi-scale conceptual framework intended to synthesize knowledge across disciplines, improve research design, and provide a broader, multi-scale model for understanding concussion pathophysiology, classification, and treatment. PMID:29033888

  1. Whole dairy matrix or single nutrients in assessment of health effects: current evidence and knowledge gaps.

    Science.gov (United States)

    Thorning, Tanja Kongerslev; Bertram, Hanne Christine; Bonjour, Jean-Philippe; de Groot, Lisette; Dupont, Didier; Feeney, Emma; Ipsen, Richard; Lecerf, Jean Michel; Mackie, Alan; McKinley, Michelle C; Michalski, Marie-Caroline; Rémond, Didier; Risérus, Ulf; Soedamah-Muthu, Sabita S; Tholstrup, Tine; Weaver, Connie; Astrup, Arne; Givens, Ian

    2017-05-01

    Foods consist of a large number of different nutrients that are contained in a complex structure. The nature of the food structure and the nutrients therein (i.e., the food matrix) will determine the nutrient digestion and absorption, thereby altering the overall nutritional properties of the food. Thus, the food matrix may exhibit a different relation with health indicators compared to single nutrients studied in isolation. The evidence for a dairy matrix effect was presented and discussed by an expert panel at a closed workshop, and the following consensus was reached: 1) Current evidence does not support a positive association between intake of dairy products and risk of cardiovascular disease (i.e., stroke and coronary heart disease) and type 2 diabetes. In contrast, fermented dairy products, such as cheese and yogurt, generally show inverse associations. 2) Intervention studies have indicated that the metabolic effects of whole dairy may be different than those of single dairy constituents when considering the effects on body weight, cardiometabolic disease risk, and bone health. 3) Different dairy products seem to be distinctly linked to health effects and disease risk markers. 4) Different dairy structures and common processing methods may enhance interactions between nutrients in the dairy matrix, which may modify the metabolic effects of dairy consumption. 5) In conclusion, the nutritional values of dairy products should not be considered equivalent to their nutrient contents but, rather, be considered on the basis of the biofunctionality of the nutrients within dairy food structures. 6) Further research on the health effects of whole dairy foods is warranted alongside the more traditional approach of studying the health effects of single nutrients. Future diet assessments and recommendations should carefully consider the evidence of the effects of whole foods alongside the evidence of the effects of individual nutrients. Current knowledge gaps and

  2. Concussion As a Multi-Scale Complex System: An Interdisciplinary Synthesis of Current Knowledge

    Directory of Open Access Journals (Sweden)

    Erin S. Kenzie

    2017-09-01

    Full Text Available Traumatic brain injury (TBI has been called “the most complicated disease of the most complex organ of the body” and is an increasingly high-profile public health issue. Many patients report long-term impairments following even “mild” injuries, but reliable criteria for diagnosis and prognosis are lacking. Every clinical trial for TBI treatment to date has failed to demonstrate reliable and safe improvement in outcomes, and the existing body of literature is insufficient to support the creation of a new classification system. Concussion, or mild TBI, is a highly heterogeneous phenomenon, and numerous factors interact dynamically to influence an individual’s recovery trajectory. Many of the obstacles faced in research and clinical practice related to TBI and concussion, including observed heterogeneity, arguably stem from the complexity of the condition itself. To improve understanding of this complexity, we review the current state of research through the lens provided by the interdisciplinary field of systems science, which has been increasingly applied to biomedical issues. The review was conducted iteratively, through multiple phases of literature review, expert interviews, and systems diagramming and represents the first phase in an effort to develop systems models of concussion. The primary focus of this work was to examine concepts and ways of thinking about concussion that currently impede research design and block advancements in care of TBI. Results are presented in the form of a multi-scale conceptual framework intended to synthesize knowledge across disciplines, improve research design, and provide a broader, multi-scale model for understanding concussion pathophysiology, classification, and treatment.

  3. The genetics of non-conventional wine yeasts: current knowledge and future challenges

    Directory of Open Access Journals (Sweden)

    Isabelle eMasneuf-Pomarede

    2016-01-01

    Full Text Available Saccharomyces cerevisiae is by far the most widely used yeast in oenology. However, during the last decade, several other yeasts species has been purposed for winemaking as they could positively impact wine quality. Some of these non-conventional yeasts (Torulaspora delbrueckii, Metschnikowia pulcherrima, Pichia kluyveri, Lachancea thermotolerans, etc. are now proposed as starters culture for winemakers in mixed fermentation with Saccharomyces cerevisiae, and several others are the subject of various studies (Hanseniaspora uvarum, Starmerella bacillaris, etc.Along with their biotechnological use, the knowledge of these non-conventional yeasts greatly increased these last ten years. The aim of this review is to describe the last updates and the current state-of-art of the genetics of non-conventional yeasts (including S. uvarum, T. delbrueckii, S. bacillaris, etc.. We describe how genomics and genetics tools provide new data into the population structure and biodiversity of non-conventional yeasts in winemaking environments. Future challenges will lie on the development of selection programs and/or genetic improvement of these non-conventional species. We discuss how genetics, genomics and the advances in next-generation sequencing will help the wine industry to develop the biotechnological use of non-conventional yeasts to improve the quality and differentiation of wines.

  4. Adult-onset autoimmune diabetes: current knowledge and implications for management.

    Science.gov (United States)

    Buzzetti, Raffaella; Zampetti, Simona; Maddaloni, Ernesto

    2017-11-01

    Adult-onset autoimmune diabetes is a heterogeneous disease that is characterized by a reduced genetic load, a less intensive autoimmune process and a mild metabolic decompensation at onset compared with young-onset type 1 diabetes mellitus (T1DM). The majority of patients with adult-onset autoimmune diabetes do not require insulin treatment for at least 6 months after diagnosis. Such patients are defined as having latent autoimmune diabetes in adults (LADA), which is distinct from classic adult-onset T1DM. The extensive heterogeneity of adult-onset autoimmune diabetes is apparent beyond the distinction between classic adult-onset T1DM and LADA. LADA is characterized by genetic, phenotypic and humoral heterogeneity, encompassing different degrees of insulin resistance and autoimmunity; this heterogeneity is probably a result of different pathological mechanisms, which have implications for treatment. The existence of heterogeneous phenotypes in LADA makes it difficult to establish an a priori treatment algorithm, and therefore, a personalized medicine approach is required. In this Review, we discuss the current understanding and gaps in knowledge regarding the pathophysiology and clinical features of adult-onset autoimmune diabetes and highlight the similarities and differences with classic T1DM and type 2 diabetes mellitus.

  5. Humpback Dolphins of Western Australia: A Review of Current Knowledge and Recommendations for Future Management.

    Science.gov (United States)

    Hanf, Daniella M; Hunt, Tim; Parra, Guido J

    2016-01-01

    Among the many cetacean species that occupy Australian coastal waters, Australian humpback dolphins, Sousa sahulensis, are one of the most vulnerable to extirpation due to human activities. This review summarises the existing knowledge, presently occurring and planned research projects, and current conservation measures for humpback dolphins in Western Australia (WA). Rapid and wide-scale coastal development along the northern WA coastline has occurred despite a lack of baseline data for inshore dolphins and, therefore, without a precautionary approach to their conservation. The distribution, abundance, habitat use, and population structure of humpback dolphins remain poorly understood. Less than 1% of their inferred distribution has so far been studied to understand local population demography. The sparse data available suggest that WA humpback dolphins occur as localised populations in low numbers within a range of inshore habitats, including both clear and turbid coastal waters. Marine protected areas cover a third of their inferred distribution in WA, but the efficacy of these reserves in protecting local cetacean populations is unknown. There is a pressing need for coordination and collaboration among scientists, government agencies, industry bodies, Traditional Owners, and local community groups to fill in the gaps of information on humpback dolphins in WA. The recently developed strategies and sampling guidelines developed by state and federal governments should serve as a best practise standard for collection of data aimed at assessing the conservation status of humpback dolphins in WA and Australia. © 2016 Elsevier Ltd. All rights reserved.

  6. Defining Established and Emerging Microbial Risks in the Aquatic Environment: Current Knowledge, Implications, and Outlooks

    Directory of Open Access Journals (Sweden)

    Neil J. Rowan

    2011-01-01

    Full Text Available This timely review primarily addresses important but presently undefined microbial risks to public health and to the natural environment. It specifically focuses on current knowledge, future outlooks and offers some potential alleviation strategies that may reduce or eliminate the risk of problematic microbes in their viable but nonculturable (VBNC state and Cryptosporidium oocysts in the aquatic environment. As emphasis is placed on water quality, particularly surrounding efficacy of decontamination at the wastewater treatment plant level, this review also touches upon other related emerging issues, namely, the fate and potential ecotoxicological impact of untreated antibiotics and other pharmaceutically active compounds in water. Deciphering best published data has elucidated gaps between science and policy that will help stakeholders work towards the European Union's Water Framework Directive (2000/60/EC, which provides an ambitious legislative framework for water quality improvements within its region and seeks to restore all water bodies to “good ecological status” by 2015. Future effective risk-based assessment and management, post definition of the plethora of dynamic inter-related factors governing the occurrence, persistence and/or control of these presently undefined hazards in water will also demand exploiting and harnessing tangential advances in allied disciplines such as mathematical and computer modeling that will permit efficient data generation and transparent reporting to be undertaken by well-balanced consortia of stakeholders.

  7. The Genetics of Non-conventional Wine Yeasts: Current Knowledge and Future Challenges.

    Science.gov (United States)

    Masneuf-Pomarede, Isabelle; Bely, Marina; Marullo, Philippe; Albertin, Warren

    2015-01-01

    Saccharomyces cerevisiae is by far the most widely used yeast in oenology. However, during the last decade, several other yeasts species has been purposed for winemaking as they could positively impact wine quality. Some of these non-conventional yeasts (Torulaspora delbrueckii, Metschnikowia pulcherrima, Pichia kluyveri, Lachancea thermotolerans, etc.) are now proposed as starters culture for winemakers in mixed fermentation with S. cerevisiae, and several others are the subject of various studies (Hanseniaspora uvarum, Starmerella bacillaris, etc.). Along with their biotechnological use, the knowledge of these non-conventional yeasts greatly increased these last 10 years. The aim of this review is to describe the last updates and the current state-of-art of the genetics of non-conventional yeasts (including S. uvarum, T. delbrueckii, S. bacillaris, etc.). We describe how genomics and genetics tools provide new data into the population structure and biodiversity of non-conventional yeasts in winemaking environments. Future challenges will lie on the development of selection programs and/or genetic improvement of these non-conventional species. We discuss how genetics, genomics and the advances in next-generation sequencing will help the wine industry to develop the biotechnological use of non-conventional yeasts to improve the quality and differentiation of wines.

  8. Influence of Electric, Magnetic, and Electromagnetic Fields on the Circadian System: Current Stage of Knowledge

    Directory of Open Access Journals (Sweden)

    Bogdan Lewczuk

    2014-01-01

    Full Text Available One of the side effects of each electrical device work is the electromagnetic field generated near its workplace. All organisms, including humans, are exposed daily to the influence of different types of this field, characterized by various physical parameters. Therefore, it is important to accurately determine the effects of an electromagnetic field on the physiological and pathological processes occurring in cells, tissues, and organs. Numerous epidemiological and experimental data suggest that the extremely low frequency magnetic field generated by electrical transmission lines and electrically powered devices and the high frequencies electromagnetic radiation emitted by electronic devices have a potentially negative impact on the circadian system. On the other hand, several studies have found no influence of these fields on chronobiological parameters. According to the current state of knowledge, some previously proposed hypotheses, including one concerning the key role of melatonin secretion disruption in pathogenesis of electromagnetic field induced diseases, need to be revised. This paper reviews the data on the effect of electric, magnetic, and electromagnetic fields on melatonin and cortisol rhythms—two major markers of the circadian system as well as on sleep. It also provides the basic information about the nature, classification, parameters, and sources of these fields.

  9. Influence of electric, magnetic, and electromagnetic fields on the circadian system: current stage of knowledge.

    Science.gov (United States)

    Lewczuk, Bogdan; Redlarski, Grzegorz; Zak, Arkadiusz; Ziółkowska, Natalia; Przybylska-Gornowicz, Barbara; Krawczuk, Marek

    2014-01-01

    One of the side effects of each electrical device work is the electromagnetic field generated near its workplace. All organisms, including humans, are exposed daily to the influence of different types of this field, characterized by various physical parameters. Therefore, it is important to accurately determine the effects of an electromagnetic field on the physiological and pathological processes occurring in cells, tissues, and organs. Numerous epidemiological and experimental data suggest that the extremely low frequency magnetic field generated by electrical transmission lines and electrically powered devices and the high frequencies electromagnetic radiation emitted by electronic devices have a potentially negative impact on the circadian system. On the other hand, several studies have found no influence of these fields on chronobiological parameters. According to the current state of knowledge, some previously proposed hypotheses, including one concerning the key role of melatonin secretion disruption in pathogenesis of electromagnetic field induced diseases, need to be revised. This paper reviews the data on the effect of electric, magnetic, and electromagnetic fields on melatonin and cortisol rhythms-two major markers of the circadian system as well as on sleep. It also provides the basic information about the nature, classification, parameters, and sources of these fields.

  10. Epidemiology of leishmaniasis in Ecuador: current status of knowledge - A review

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    Manuel Calvopina

    2004-11-01

    Full Text Available Although leishmaniasis is regarded as a significant health problem in Ecuador by the Ministry of Health, and the incidence has increased over the last years, an official map on the geographic distribution of disease and sand fly vectors or a control strategy do not exist yet. This article reviews the current situation based on published information to improve our knowledge and understand the epidemiological situation of leishmaniasis in Ecuador in order to help future research and to develop a national control strategy. The disease is endemic in most provinces throughout Pacific coastal region, Amazonian lowlands, and some inter-Andean valleys with a total 21,805 cases reported during 1990-2003. Whereas cutaneous leishmaniasis (CL is found throughout Ecuador, mucocutaneous leishmaniasis (MCL appears to be restricted to the Amazon region; one, parasitologically unconfirmed case of visceral form was reported in 1949. Most human infections are caused by Leishmania (Viannia spp., which is distributed in the subtropical and tropical lowlands; infections due to L. (Leishmania spp. are found in the Andean highlands and in the Pacific lowlands as well. The proven vectors are Lutzomyia trapidoi and Lu. ayacuchensis. Canis familiaris, Sciurus vulgaris, Potos flavus, and Tamandua tetradactyla have been found infected with Leishmania spp. It is estimated that around 3000-4500 people may be infected every year, and that 3.1 to 4.5 millions people are estimated to be at risk of contracting leishmaniasis.

  11. Cassava brown streak disease: historical timeline, current knowledge and future prospects.

    Science.gov (United States)

    Tomlinson, Katie R; Bailey, Andy M; Alicai, Titus; Seal, Sue; Foster, Gary D

    2017-09-08

    Cassava is the second most important staple food crop in terms of per capita calories consumed in Africa and holds potential for climate change adaptation. Unfortunately, productivity in East and Central Africa is severely constrained by two viral diseases: cassava mosaic disease (CMD) and cassava brown streak disease (CBSD). CBSD was first reported in 1936 from northeast Tanzania. For approximately seventy years CBSD was restricted to coastal East Africa and so had a relatively low impact on food security compared to CMD. However, at the turn of the 21st century CBSD re-emerged further inland, in areas around Lake Victoria and it has since spread through many East and Central African countries, causing high yield losses and jeopardising the food security of subsistence farmers. This recent re-emergence has attracted intense scientific interest, with studies shedding light on CBSD viral epidemiology, sequence diversity, host interactions and potential sources of resistance within the cassava genome. This review reflects on 80 years of CBSD research history (1936 - 2016) with a timeline of key events. We provide insights into current CBSD knowledge, management efforts and future prospects for improved understanding needed to underpin effective control and mitigation of impacts on food security. This article is protected by copyright. All rights reserved. © 2017 BSPP and John Wiley & Sons Ltd.

  12. Nitric Oxide (NO in Plant Heat Stress Tolerance: Current Knowledge and Perspectives

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    Santisree Parankusam

    2017-09-01

    Full Text Available High temperature is one of the biggest abiotic stress challenges for agriculture. While, Nitric oxide (NO is gaining increasing attention from plant science community due to its involvement in resistance to various plant stress conditions, its implications on heat stress tolerance is still unclear. Several lines of evidence indicate NO as a key signaling molecule in mediating various plant responses such as photosynthesis, oxidative defense, osmolyte accumulation, gene expression, and protein modifications under heat stress. Furthermore, the interactions of NO with other signaling molecules and phytohormones to attain heat tolerance have also been building up in recent years. Nevertheless, deep insights into the functional intermediaries or signal transduction components associated with NO-mediated heat stress signaling are imperative to uncover their involvement in plant hormone induced feed-back regulations, ROS/NO balance, and stress induced gene transcription. Although, progress is underway, much work remains to define the functional relevance of this molecule in plant heat tolerance. This review provides an overview on current status and discuss knowledge gaps in exploiting NO, thereby enhancing our understanding of the role of NO in plant heat tolerance.

  13. The iron-sulfur cluster assembly machineries in plants: current knowledge and open questions

    Science.gov (United States)

    Couturier, Jérémy; Touraine, Brigitte; Briat, Jean-François; Gaymard, Frédéric; Rouhier, Nicolas

    2013-01-01

    Many metabolic pathways and cellular processes occurring in most sub-cellular compartments depend on the functioning of iron-sulfur (Fe-S) proteins, whose cofactors are assembled through dedicated protein machineries. Recent advances have been made in the knowledge of the functions of individual components through a combination of genetic, biochemical and structural approaches, primarily in prokaryotes and non-plant eukaryotes. Whereas most of the components of these machineries are conserved between kingdoms, their complexity is likely increased in plants owing to the presence of additional assembly proteins and to the existence of expanded families for several assembly proteins. This review focuses on the new actors discovered in the past few years, such as glutaredoxin, BOLA and NEET proteins as well as MIP18, MMS19, TAH18, DRE2 for the cytosolic machinery, which are integrated into a model for the plant Fe-S cluster biogenesis systems. It also discusses a few issues currently subjected to an intense debate such as the role of the mitochondrial frataxin and of glutaredoxins, the functional separation between scaffold, carrier and iron-delivery proteins and the crosstalk existing between different organelles. PMID:23898337

  14. The effects of strontium on bone mineral: A review on current knowledge and microanalytical approaches.

    Science.gov (United States)

    Querido, William; Rossi, Andre L; Farina, Marcos

    2016-01-01

    The interest in effects of strontium (Sr) on bone has greatly increased in the last decade due to the development of the promising drug strontium ranelate. This drug is used for treating osteoporosis, a major bone disease affecting hundreds of millions of people worldwide, especially postmenopausal women. The novelty of strontium ranelate compared to other treatments for osteoporosis is its unique effect on bone: it simultaneously promotes bone formation by osteoblasts and inhibits bone resorption by osteoclasts. Besides affecting bone cells, treatment with strontium ranelate also has a direct effect on the mineralized bone matrix. Due to the chemical similarities between Sr and Ca, a topic that has long been of particular interest is the incorporation of Sr into bones replacing Ca from the mineral phase, which is composed by carbonated hydroxyapatite nanocrystals. Several groups have analyzed the mineral produced during treatment; however, most analysis were done with relatively large samples containing numerous nanocrystals, resulting thus on data that represents an average of many crystalline domains. The nanoscale analysis of the bone apatite crystals containing Sr has only been described in a few studies. In this study, we review the current knowledge on the effects of Sr on bone mineral and discuss the methodological approaches that have been used in the field. In particular, we focus on the great potential that advanced microscopy and microanalytical techniques may have on the detailed analysis of the nanostructure and composition of bone apatite nanocrystals produced during treatment with strontium ranelate. Copyright © 2015. Published by Elsevier Ltd.

  15. Brugada Syndrome and Exercise Practice: Current Knowledge, Shortcomings and Open Questions.

    Science.gov (United States)

    Mascia, Giuseppe; Arbelo, Elena; Ojeda, Jaime Hernández; Solimene, Francesco; Brugada, Ramon; Brugada, Josep

    2017-07-01

    Since its recognition as a clinical entity in 1992, the Brugada Syndrome (BrS), a hereditary disease characterized by a typical electrocardiogram (ECG) pattern potentially predisposing to sudden cardiac death (SCD), has attracted the attention of many physicians for its circadian pattern of ventricular arrhythmias (VA), mostly occurring at rest. Exercise may potentially worsen the ECG abnormalities in BrS patients, resulting in higher peak J-point amplitudes during the vasovagal reaction of the recovery period, possibly leading to an increased risk of cardiac events. Moreover, the enhanced vagal tone in athletes could be both a BrS risk factor and an exercise effect. Therefore, the true risk of a BrS patient during exercise is still unclear. This review summarizes current knowledge, shortcomings and open questions on BrS and exercise. The paper, in particular, underlines specific considerations including BrS diagnostic criteria and differential diagnosis in athletes, the genetic basis, the autonomic imbalance during exercise practice and the recommendations for athletic participation in this patient group. © Georg Thieme Verlag KG Stuttgart · New York.

  16. Tropical forest responses to increasing [CO2]: current knowledge and opportunities for future research

    Energy Technology Data Exchange (ETDEWEB)

    Cernusak, Lucas [Australian National University, Canberra, Australia; Winter, Klaus [Smithsonian Tropical Research Institute; Dalling, James [University of Illinois, Urbana-Champaign; Holtum, Joseph [James Cook University; Jaramillo, Carlos [Smithsonian Tropical Research Institute; Korner, Christian [University of Basel; Leakey, Andrew D.B. [University of Illinois; Norby, Richard J [ORNL; Poulter, Benjamin [Laboratoire des Sciences du Climat et de l' Environement, France; Turner, Benjamin [Smithsonian Tropical Research Institute; Wright, S. Joseph [Smithsonian Tropical Research Institute

    2013-01-01

    Elevated atmospheric [CO2] (ca) will undoubtedly affect the metabolism of tropical forests worldwide; however, critical aspects of how tropical forests will respond remain largely unknown. Here we review the current state of knowledge about physiological and ecological responses, with the aim of providing a framework that can help to guide future experimental research. Modelling studies have indicated that elevated ca can potentially stimulate photosynthesis more in the tropics than at higher latitudes, because suppression of photorespiration by elevated ca increases with temperature. However, canopy leaves in tropical forests could also potentially reach a high temperature threshold under elevated ca that will moderate the rise in photosynthesis. Belowground responses, including fine root production, nutrient foraging, and soil organic matter processing, will be especially important to the integrated ecosystem response to elevated CO2. Water-use efficiency will increase as ca rises, potentially impacting upon soil moisture status and nutrient availability. Recruitment may be differentially altered for some functional groups, potentially decreasing ecosystem carbon storage. Whole-forest CO2 enrichment experiments are urgently needed to test predictions of tropical forest functioning under elevated ca. Smaller scale experiments in the understory and in gaps would also be informative, and could provide stepping stones toward stand-scale manipulations.

  17. The Genetic Basis of Peripheral Arterial Disease: Current Knowledge, Challenges and Future Directions

    Science.gov (United States)

    Kullo, Iftikhar J.; Leeper, Nicholas J.

    2015-01-01

    Several risk factors for atherosclerotic peripheral arterial disease (PAD) such as dyslipidemia, diabetes and hypertension, are heritable. However, predisposition to PAD may be influenced by genetic variants acting independently of these risk factors. Identification of such genetic variants will provide insights into underlying pathophysiologic mechanisms and facilitate the development of novel diagnostic and therapeutic approaches. In contrast to coronary heart disease, relatively few genetic variants that influence susceptibility to PAD have been discovered. This may be in part due to greater clinical and genetic heterogeneity in PAD. In this review, we a) provide an update on the current state of knowledge about the genetic basis of PAD including results of family studies and candidate gene, linkage as well as genome-wide association studies; b) highlight the challenges in investigating the genetic basis of PAD and possible strategies to overcome these challenges; and c) discuss the potential of genome sequencing, RNA sequencing, differential gene expression, epigenetic profiling and systems biology in increasing our understanding of the molecular genetics of PAD. PMID:25908728

  18. Patient knowledge, perceptions, and acceptance of generic medicines: a comprehensive review of the current literature

    Directory of Open Access Journals (Sweden)

    Alrasheedy AA

    2014-04-01

    Full Text Available Alian A Alrasheedy,1 Mohamed Azmi Hassali,1 Kay Stewart,2 David CM Kong,2 Hisham Aljadhey,3 Mohamed Izham Mohamed Ibrahim,4 Saleh Karamah Al-Tamimi1 1Discipline of Social and Administrative Pharmacy, School of Pharmaceutical Sciences, Universiti Sains Malaysia, Penang, Malaysia; 2Faculty of Pharmacy and Pharmaceutical Sciences, Monash University, Melbourne, VIC, Australia; 3Medication Safety Research Chair, Clinical Pharmacy Department, College of Pharmacy, King Saud University, Riyadh, Saudi Arabia; 4College of Pharmacy, Qatar University, Doha, Qatar Background: Generic medicines have the same quality, safety, and efficacy as their counterpart original brand medicines. Generic medicines provide the same therapeutic outcomes but at a much cheaper cost, so are promoted in many countries to contain pharmaceutical expenditure and sustain the health care system. Thus, the perspective of patients and medicine consumers as end users of these medicines is an important factor to enhance the use and utilization of generic medicines. The objective of this paper is to review patients’ and consumers’ knowledge, perceptions, acceptance, and views of generic medicines in the current literature. Methods: An extensive literature search was performed in several databases, namely Scopus, PubMed, ISI Web of Knowledge, Proquest, and the Wiley online library, to identify relevant studies published in the English literature for the period 1990–2013. Results: A total of 53 studies were included in the review, comprising 24 studies from Europe, ten from North America, six from Asia, five from Australia and New Zealand, five from the Middle East, one from Africa, one from Latin America, and one from the Caribbean region. A large body of literature has reported misconceptions and negative perceptions about generic medicines on the part of patients and medicine consumers. Moreover, although it is reported in almost all countries, the percentage of consumers who had

  19. PET motion correction in context of integrated PET/MR: Current techniques, limitations, and future projections.

    Science.gov (United States)

    Gillman, Ashley; Smith, Jye; Thomas, Paul; Rose, Stephen; Dowson, Nicholas

    2017-12-01

    Patient motion is an important consideration in modern PET image reconstruction. Advances in PET technology mean motion has an increasingly important influence on resulting image quality. Motion-induced artifacts can have adverse effects on clinical outcomes, including missed diagnoses and oversized radiotherapy treatment volumes. This review aims to summarize the wide variety of motion correction techniques available in PET and combined PET/CT and PET/MR, with a focus on the latter. A general framework for the motion correction of PET images is presented, consisting of acquisition, modeling, and correction stages. Methods for measuring, modeling, and correcting motion and associated artifacts, both in literature and commercially available, are presented, and their relative merits are contrasted. Identified limitations of current methods include modeling of aperiodic and/or unpredictable motion, attaining adequate temporal resolution for motion correction in dynamic kinetic modeling acquisitions, and maintaining availability of the MR in PET/MR scans for diagnostic acquisitions. Finally, avenues for future investigation are discussed, with a focus on improvements that could improve PET image quality, and that are practical in the clinical environment. © 2017 American Association of Physicists in Medicine.

  20. Combining Pharmacological and Psychological Treatments for Binge Eating Disorder: Current Status, Limitations, and Future Directions.

    Science.gov (United States)

    Grilo, Carlos M; Reas, Deborah L; Mitchell, James E

    2016-06-01

    Binge eating disorder (BED) is characterized by recurrent binge eating and marked distress about binge eating without the extreme compensatory behaviors for weight control that characterize other eating disorders. BED is prevalent, associated strongly with obesity, and is associated with heightened levels of psychological, psychiatric, and medical concerns. This article provides an overview of randomized controlled treatments for combined psychological and pharmacological treatment of BED to inform current clinical practice and future treatment research. In contrast to the prevalence and significance of BED, to date, limited research has been performed on combining psychological and pharmacological treatments for BED to enhance outcomes. Our review here found that combining certain medications with cognitive behavioral therapy (CBT) or behavioral weight loss (BWL) interventions produces superior outcomes to pharmacotherapy only but does not substantially improve outcomes achieved with CBT/BWL only. One medication (orlistat) has improved weight losses with CBT/BWL albeit minimally, and only one medication (topiramate) has enhanced reductions achieved with CBT in both binge eating and weight. Implications for future research are discussed.

  1. Exploring Issues Limiting the Use of Knowledge in Disaster Risk Reduction.

    Directory of Open Access Journals (Sweden)

    John Norton

    2015-10-01

    A final conclusion is that no matter how useful, knowledge itself is not a panacea for DRR. Decision-making is invariably influenced by conflicting priorities, objectives and constraints, and not necessarily in all stakeholders’ interests or even reflecting their objectives. For example in the midst of the Greek economic crisis, disaster risk awareness and acceptability are becoming less a matter of DRR information and knowledge and must rather be addressed with a view to the new hierarchy of risks (socio-economic, health, emerging generated by the crisis. However, acknowledging the complexity of the issue should not stand in the way of much needed efforts towards enabling knowledge for DRR with all the tools available in today’s changing world.

  2. A Prior Knowledge-Based Method to Derivate High-Resolution Leaf Area Index Maps with Limited Field Measurements

    Directory of Open Access Journals (Sweden)

    Yuechan Shi

    2016-12-01

    Full Text Available High-resolution leaf area index (LAI maps from remote sensing data largely depend on empirical models, which link field LAI measurements to the vegetation index. The existing empirical methods often require the field measurements to be sufficient for constructing a reliable model. However, in many regions of the world, there are limited field measurements available. This paper presents a prior knowledge-based (PKB method to derivate LAI with limited field measurements, in an effort to improve the accuracy of empirical model. Based on the assumption that the experimental sites with the same vegetation type can be represented by similar models, a priori knowledge for crops was extracted from the published models in various cropland sites. The knowledge, composed of an initial guess of each model parameter with the associated uncertainty, was then combined with the local field measurements to determine a semi-empirical model using the Bayesian inversion method. The proposed method was evaluated at a cropland site in the Huailai region of Hebei Province, China. Compared with the regression method, the proposed PKB method can effectively improve the accuracy of empirical model and LAI estimation, when the field measurements were limited. The results demonstrate that a priori knowledge extracted from the universal sites can provide important auxiliary information to improve the representativeness of the empirical model in a given study area.

  3. Care pathways in US healthcare settings: current successes and limitations, and future challenges.

    Science.gov (United States)

    Chawla, Anita; Westrich, Kimberly; Matter, Susanna; Kaltenboeck, Anna; Dubois, Robert

    2016-01-01

    Care pathways are used widely in US healthcare settings and are expected to have greater influence on quality of care and patient outcomes in the future. We conducted qualitative research to evaluate the state of care pathways and their impact in the United States. Targeted literature review followed by an online survey and in-person interviews. The PubMed and Cochrane databases were searched for publications on care pathways (January 1, 2005, to July 21, 2014) to inform the subsequent surveys and interviews with payers, providers, and pathway vendors regarding care pathway design, development, and management. A targeted hand search was completed in May 2015 to supplement the earlier review. Twenty-nine publications, posters, or abstracts on specific care pathways were identified; the online survey and follow-up interviews included 26 and 18 respondents, respectively. Positive trends in current care pathways development and implementation include prioritization of high-quality evidence, enhancing the role of providers in development and implementation, and flexibility for providers to tailor treatment decisions to patients' needs. Nevertheless, there are some limitations in methodology for development and implementation, in criteria for evaluation, and in the degree of transparency surrounding these activities. Our research confirms that high-quality evidence of efficacy and safety are expected to be central to future pathway development, and that physicians play a major role in development and implementation. To achieve the goals of improving quality of care while managing costs, further efforts are required regarding systematic development and evaluation, consistent implementation and compliance metrics, and transparency in implementation outcomes and financial motivators.

  4. Scanning fast and slow: current limitations of 3 Tesla functional MRI and future potential

    Science.gov (United States)

    Boubela, Roland N.; Kalcher, Klaudius; Nasel, Christian; Moser, Ewald

    2017-01-01

    Functional MRI at 3T has become a workhorse for the neurosciences, e.g., neurology, psychology, and psychiatry, enabling non-invasive investigation of brain function and connectivity. However, BOLD-based fMRI is a rather indirect measure of brain function, confounded by physiology related signals, e.g., head or brain motion, brain pulsation, blood flow, intermixed with susceptibility differences close or distant to the region of neuronal activity. Even though a plethora of preprocessing strategies have been published to address these confounds, their efficiency is still under discussion. In particular, physiological signal fluctuations closely related to brain supply may mask BOLD signal changes related to “true” neuronal activation. Here we explore recent technical and methodological advancements aimed at disentangling the various components, employing fast multiband vs. standard EPI, in combination with fast temporal ICA. Our preliminary results indicate that fast (TR <0.5 s) scanning may help to identify and eliminate physiologic components, increasing tSNR and functional contrast. In addition, biological variability can be studied and task performance better correlated to other measures. This should increase specificity and reliability in fMRI studies. Furthermore, physiological signal changes during scanning may then be recognized as a source of information rather than a nuisance. As we are currently still undersampling the complexity of the brain, even at a rather coarse macroscopic level, we should be very cautious in the interpretation of neuroscientific findings, in particular when comparing different groups (e.g., age, sex, medication, pathology, etc.). From a technical point of view our goal should be to sample brain activity at layer specific resolution with low TR, covering as much of the brain as possible without violating SAR limits. We hope to stimulate discussion toward a better understanding and a more quantitative use of fMRI. PMID:28164083

  5. Scanning fast and slow: current limitations of 3 Tesla functional MRI and future potential

    Directory of Open Access Journals (Sweden)

    Roland N Boubela

    2014-02-01

    Full Text Available Functional MRI at 3T has become a workhorse for the neurosciences, e.g., neurology, psychology, and psychiatry, enabling non-invasive investigation of brain function and connectivity. However, BOLD-based fMRI is a rather indirect measure of brain function, confounded by fluctuation related signals, e.g. head or brain motion, brain pulsation, blood flow, intermixed with susceptibility differences close or distant to the region of neuronal activity. Even though a plethora of preprocessing strategies have been published to address these confounds, their efficiency is still under discussion. In particular, physiological signal fluctuations closely related to brain supply may mask BOLD signal changes related to true neuronal activation. Here we explore recent technical and methodological advancements aimed at disentangling the various components, employing fast multiband vs. standard EPI, in combination with fast temporal ICA.Our preliminary results indicate that fast (TR< 0.5s scanning may help to identify and eliminate physiologic components, increasing tSNR and functional contrast. In addition, biological variability can be studied and task performance better correlated to other measures. This should increase specificity and reliability in fMRI studies. Furthermore, physiological signal changes during scanning may then be recognized as a source of information rather than a nuisance. As we are currently still undersampling the complexity of the brain, even at a rather coarse macroscopic level, we should be very cautious in the interpretation of neuroscientific findings, in particular when comparing different groups (e.g., age, sex, medication, pathology, etc.. From a technical point of view our goal should be to sample brain activity at layer specific resolution with low TR, covering as much of the brain as possible without violating SAR limits. We hope to stimulate discussion towards a better understanding and a more quantitative use of fMRI.

  6. Scanning fast and slow: current limitations of 3 Tesla functional MRI and future potential

    Science.gov (United States)

    Boubela, Roland N.; Kalcher, Klaudius; Nasel, Christian; Moser, Ewald

    2014-02-01

    Functional MRI at 3T has become a workhorse for the neurosciences, e.g., neurology, psychology, and psychiatry, enabling non-invasive investigation of brain function and connectivity. However, BOLD-based fMRI is a rather indirect measure of brain function, confounded by fluctuation related signals, e.g. head or brain motion, brain pulsation, blood flow, intermixed with susceptibility differences close or distant to the region of neuronal activity. Even though a plethora of preprocessing strategies have been published to address these confounds, their efficiency is still under discussion. In particular, physiological signal fluctuations closely related to brain supply may mask BOLD signal changes related to "true" neuronal activation. Here we explore recent technical and methodological advancements aimed at disentangling the various components, employing fast multiband vs. standard EPI, in combination with fast temporal ICA.Our preliminary results indicate that fast (TReliminate physiologic components, increasing tSNR and functional contrast. In addition, biological variability can be studied and task performance better correlated to other measures. This should increase specificity and reliability in fMRI studies. Furthermore, physiological signal changes during scanning may then be recognized as a source of information rather than a nuisance. As we are currently still undersampling the complexity of the brain, even at a rather coarse macroscopic level, we should be very cautious in the interpretation of neuroscientific findings, in particular when comparing different groups (e.g., age, sex, medication, pathology, etc.). From a technical point of view our goal should be to sample brain activity at layer specific resolution with low TR, covering as much of the brain as possible without violating SAR limits. We hope to stimulate discussion towards a better understanding and a more quantitative use of fMRI.

  7. Synthesis of current knowledge on post-fire seeding for soil stabilization and invasive species control

    Science.gov (United States)

    Beyers, Jan L.; Pyke, David A.; Wirth, Troy

    2015-01-01

    The General Accounting Office has identified a need for better information on the effectiveness of post-fire emergency stabilization and rehabilitation methods used by the U.S. Forest Service and Department of Interior (DOI) agencies. Since reviews were published on treatment effectiveness in the early 2000s, treatment choices have changed and increased monitoring has been done. Greater use of native species has added substantially to burned area emergency response (BAER) treatment costs, for example, but quantitative data on this treatment were scarce in earlier reviews. We synthesized current information on the effectiveness of post-fire seeding for both soil stabilization and for prevention of the spread of invasive species in rangelands. We reviewed published literature (peer-reviewed and “gray”) and agency monitoring reports, as well as compiled and analyzed quantitative data in agency files. Products of this review include a web-accessible database of monitoring reports and published information, a scientific journal paper summarizing findings of scientific studies, an annotated bibliography of peer-reviewed papers, a summary report published as a General Technical Report that will be available online (in progress), and presentations to scientific meetings and BAER/ESR team training sessions and workshops. By combining results from studies done by Forest Service and DOI agency personnel with research studies published since the initial reviews, we presented a comprehensive synthesis of seeding effectiveness knowledge that complements the review of other hillslope treatments published by other researchers. This information will help federal land managers make more cost-effective decisions on post-fire stabilization and rehabilitation treatments.

  8. Current knowledge of tooth development: patterning and mineralization of the murine dentition.

    Science.gov (United States)

    Catón, Javier; Tucker, Abigail S

    2009-04-01

    The integument forms a number of different types of mineralized element, including dermal denticles, scutes, ganoid scales, elasmoid scales, fin rays and osteoderms found in certain fish, reptiles, amphibians and xenarthran mammals. To this list can be added teeth, which are far more widely represented and studied than any of the other mineralized elements mentioned above, and as such can be thought of as a model mineralized system. In recent years the focus for studies on tooth development has been the mouse, with a wealth of genetic information accrued and the availability of cutting edge techniques. It is the mouse dentition that this review will concentrate on. The development of the tooth will be followed, looking at what controls the shape of the tooth and how signals from the mesenchyme and epithelium interact to lead to formation of a molar or incisor. The number of teeth generated will then be investigated, looking at how tooth germ number can be reduced or increased by apoptosis, fusion of tooth germs, creation of new tooth germs, and the generation of additional teeth from existing tooth germs. The development of mineralized tissue will then be detailed, looking at how the asymmetrical deposition of enamel is controlled in the mouse incisor. The continued importance of epithelial-mesenchymal interactions at these later stages of tooth development will also be discussed. Tooth anomalies and human disorders have been well covered by recent reviews, therefore in this paper we wish to present a classical review of current knowledge of tooth development, fitting together data from a large number of recent research papers to draw general conclusions about tooth development.

  9. Genetic considerations for mollusc production in aquaculture: current state of knowledge.

    Directory of Open Access Journals (Sweden)

    Marcela eAstorga

    2014-12-01

    Full Text Available IIn 2012, world mollusk production in aquaculture reached a volume of 15,171,000 tons, representing 23% of total aquaculture production and positioning mollusks as the second most important category of aquaculture products (fishes are the first. Clams and oysters are the mollusk species with the highest production levels, followed in descending order by mussels, scallops and abalones. In view of the increasing importance attached to genetic information on aquaculture, which can help with good maintenance and thus the sustainability of production, the present work offers a review of the state of knowledge on genetic and genomic information about mollusks produced in aquaculture. The analysis was applied to mollusks which are of importance for aquaculture, with emphasis on the 5 species with the highest production levels. According to FAO, these are: Japanese clam Ruditapes philippinarum; Pacific oyster Crassostrea gigas; Chilean mussel Mytilus chilensis; Blood clam Anadara granosa and Chinese clam Sinonovacula constricta. To date, the genomes of 5 species of mollusks have been sequenced, only one of which, Crassostrea gigas, coincides with the species with the greatest production in aquaculture. Another important species whose genome has been sequenced is Mytilus galloprovincialis, which is the second most important mussel in aquaculture production, after M. chilensis. Few genetic improvement programs have been reported in comparison with the number reported in fish species. The most commonly investigated species are oysters, with at least 5 genetic improvement programs reported, followed by abalones with 2 programs and mussels with one. The results of this work will establish the current situation with respect to the genetics of mollusks which are of importance for aquaculture production, in order to assist future decisions to ensure the sustainability of these resources.

  10. Unconscious structural knowledge of tonal symmetry: Tang poetry redefines limits of implicit learning.

    Science.gov (United States)

    Jiang, Shan; Zhu, Lei; Guo, Xiuyan; Ma, Wendy; Yang, Zhiliang; Dienes, Zoltan

    2012-03-01

    The study aims to help characterize the sort of structures about which people can acquire unconscious knowledge. It is already well established that people can implicitly learn n-grams (chunks) and also repetition patterns. We explore the acquisition of unconscious structural knowledge of symmetry. Chinese Tang poetry uses a specific sort of mirror symmetry, an inversion rule with respect to the tones of characters in successive lines of verse. We show, using artificial poetry to control both n-gram structure and repetition patterns, that people can implicitly learn to discriminate inversions from non-inversions, presenting a challenge to existing models of implicit learning. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. A convenient dichotomy: critical eyes on the limits to biological knowledge

    Science.gov (United States)

    Milne, Catherine

    2011-06-01

    In The Secret Identity of a Biology Textbook: straight and naturally sexed, Jesse Bazzul and Heather Sykes conduct a case study of a biology textbook as an oppressive instructional material. Using queer theory they explore how the text of the biology textbook produces "truths" about sex, gender, and sexuality. Their analysis is complemented by the Forum papers by Jay Lemke and Francis Broadway who broaden the analysis examining the way that what counts as knowledge in science is a political decision while also encouraging authors, including Bazzul and Sykes, to also look critically at their own theoretical lenses. In this paper I pull together their ideas while exploring cultural contexts for a more nuanced representation of biological knowledge and the politics of what it means to know science.

  12. Photocatalytic effects of titanium dioxide nanoparticles on aquatic organisms-Current knowledge and suggestions for future research.

    Science.gov (United States)

    Haynes, Vena N; Ward, J Evan; Russell, Brandon J; Agrios, Alexander G

    2017-04-01

    Nanoparticles are entering natural systems through product usage, industrial waste and post-consumer material degradation. As the production of nanoparticles is expected to increase in the next decade, so too are predicted environmental loads. Engineered metal-oxide nanomaterials, such as titanium dioxide, are known for their photocatalytic capabilities. When these nanoparticles are exposed to ultraviolet radiation in the environment, however, they can produce radicals that are harmful to aquatic organisms. There have been a number of studies that have reported the toxicity of titanium dioxide nanoparticles in the absence of light. An increasing number of studies are assessing the interactive effects of nanoparticles and ultraviolet light. However, most of these studies neglect environmentally-relevant experimental conditions. For example, researchers are using nanoparticle concentrations and light intensities that are too high for natural systems, and are ignoring water constituents that can alter the light field. The purpose of this review is to summarize the current knowledge of the photocatalytic effects of TiO2 nanoparticles on aquatic organisms, discuss the limitations of these studies, and outline environmentally-relevant factors that need to be considered in future experiments. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Photocatalytic effects of titanium dioxide nanoparticles on aquatic organisms—Current knowledge and suggestions for future research

    Energy Technology Data Exchange (ETDEWEB)

    Haynes, Vena N., E-mail: vena.haynes@uconn.edu [University of Connecticut, Department of Marine Sciences, 1080 Shennecossett Road, Groton, CT 06340 (United States); Ward, J. Evan, E-mail: evan.ward@uconn.edu [University of Connecticut, Department of Marine Sciences, 1080 Shennecossett Road, Groton, CT 06340 (United States); Russell, Brandon J., E-mail: brandon.russell@uconn.edu [University of Connecticut, Department of Marine Sciences, 1080 Shennecossett Road, Groton, CT 06340 (United States); Agrios, Alexander G., E-mail: agrios@engr.uconn.edu [University of Connecticut, Department of Civil & Environmental Engineering, 261 Glenbrook Road Unit 3037, Storrs, CT 06269 (United States)

    2017-04-15

    Highlights: • Ecotoxicological approaches are needed to predict effects of photoactive nanomaterials. • Research on effects of photoactive nanomaterials must include defined light fields. • Light fields must be appropriate for depth, latitude, season and water properties. • Physicochemical properties of water can alter light fields and photoreactivity. - Abstract: Nanoparticles are entering natural systems through product usage, industrial waste and post-consumer material degradation. As the production of nanoparticles is expected to increase in the next decade, so too are predicted environmental loads. Engineered metal-oxide nanomaterials, such as titanium dioxide, are known for their photocatalytic capabilities. When these nanoparticles are exposed to ultraviolet radiation in the environment, however, they can produce radicals that are harmful to aquatic organisms. There have been a number of studies that have reported the toxicity of titanium dioxide nanoparticles in the absence of light. An increasing number of studies are assessing the interactive effects of nanoparticles and ultraviolet light. However, most of these studies neglect environmentally-relevant experimental conditions. For example, researchers are using nanoparticle concentrations and light intensities that are too high for natural systems, and are ignoring water constituents that can alter the light field. The purpose of this review is to summarize the current knowledge of the photocatalytic effects of TiO{sub 2} nanoparticles on aquatic organisms, discuss the limitations of these studies, and outline environmentally-relevant factors that need to be considered in future experiments.

  14. Innate and adaptive immunity in the development of depression: An update on current knowledge and technological advances.

    Science.gov (United States)

    Haapakoski, Rita; Ebmeier, Klaus P; Alenius, Harri; Kivimäki, Mika

    2016-04-03

    The inflammation theory of depression, proposed over 20years ago, was influenced by early studies on T cell responses and since then has been a stimulus for numerous research projects aimed at understanding the relationship between immune function and depression. Observational studies have shown that indicators of immunity, especially C reactive protein and proinflammatory cytokines, such as interleukin 6, are associated with an increased risk of depressive disorders, although the evidence from randomized trials remains limited and only few studies have assessed the interplay between innate and adaptive immunity in depression. In this paper, we review current knowledge on the interactions between central and peripheral innate and adaptive immune molecules and the potential role of immune-related activation of microglia, inflammasomes and indoleamine-2,3-dioxygenase in the development of depressive symptoms. We highlight how combining basic immune methods with more advanced 'omics' technologies would help us to make progress in unravelling the complex associations between altered immune function and depressive disorders, in the identification of depression-specific biomarkers and in developing immunotherapeutic treatment strategies that take individual variability into account. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  15. Knowledges

    DEFF Research Database (Denmark)

    Berling, Trine Villumsen

    2012-01-01

    Scientific knowledge in international relations has generally focused on an epistemological distinction between rationalism and reflectivism over the last 25 years. This chapter argues that this distinction has created a double distinction between theory/reality and theory/practice, which works...... as a ghost distinction structuring IR research. While reflectivist studies have emphasised the impossibility of detached, objective knowledge production through a dissolution of the theory/reality distinction, the theory/practice distinction has been left largely untouched by both rationalism...... on the interrelationship between theory and practice in specific domains, while at the same time foregrounding the own position of the researcher. The transformation of European security in the 1990s is taken as an example of how an IR analysis changes focus when seeing knowledge as Bourdieu....

  16. Formation of a spark discharge in an inhomogeneous electric field with current limitation by a large ballast Resistance

    Energy Technology Data Exchange (ETDEWEB)

    Baldanov, B. B., E-mail: baibat@mail.ru [Russian Academy of Sciences, Institute of Physical Material Science, Siberian Branch (Russian Federation)

    2016-01-15

    Results of studies of a spark discharge initiated in argon in a point–plane electrode gap with limitation of the discharge current by a large ballast resistance are presented. It is shown that the current flowing through the plasma channel of such a low-current spark has the form of periodic pulses. It is experimentally demonstrated that, when a low-current spark transforms into a constricted glow discharge, current pulses disappear, the spatial structure of the cathode glow changes abruptly, and a brightly glowing positive plasma column forms in the gap.

  17. Limited knowledge of chronic kidney disease among primary care patients – a cross-sectional survey

    Directory of Open Access Journals (Sweden)

    Chow Wai

    2012-07-01

    Full Text Available Abstract Background Kidney disease is the 9th leading cause of death in Singapore. While preventive effects have focused on early detection and education, little is known about the knowledge level of chronic kidney disease (CKD locally. We seek to evaluate the knowledge of CKD among primary care patients. Methods We conducted a cross-sectional survey of a convenience sample of 1520 patients from 3 primary care centers. Those with existing CKD or on dialysis were excluded. Knowledge was assessed based on 7 questions on CKD in the self-administered questionnaire. One point was given for each correct answer with a maximum of 7 points. Results 1435 completed all 7 questions on CKD. Mean age was 48.9 ±15.0 (SD years. 50.9% were male. 62.3% had a secondary and below education and 52.4% had a monthly household income of ≤ $2000. 43.7% had chronic diseases. Mean score was 3.44 ± 1.53 (out of a maximum of 7. Median score was 4. In multivariate logistic regression, being older {>60 years [Odds Ratio (OR 0.50, 95% Confidence Interval (CI 0.32-0.79]; 40–60 years (OR 0.62, 95% CI 0.43,0.89}, less educated [up to primary education (OR 0.33, 95% CI 0.22-0.49], having a lower monthly household income [ Conclusion This suggests that CKD education should be targeted at older patients with lower education and lower socioeconomic status.

  18. Improvement of Protection Coordination for a Distribution System Connected to a Microgrid using Unidirectional Fault Current Limiter

    Directory of Open Access Journals (Sweden)

    Mazen Abdel-Salam

    2017-09-01

    Full Text Available The presence of distributed generation (DG units in distribution systems increases the fault current level, which disrupts the existing coordination time interval of the protective overcurrent relays. One of the ways for decreasing DG effects on the coordination of protective devices is re-coordination of the relays by installing unidirectional fault current limiter (UFCL between the main grid (upstream network and the microgrid (downstream network. The UFCL does not limit fault current contribution of the upstream network when fault occurs in downstream but limits fault current contribution of the downstream network when fault occurs in the upstream. Moreover, it preserves the coordination between all of the relays. Several case studies are carried out for illustrating the performance of the UFCL in maintaining the relay coordination.

  19. [Prevention of cervical cancer (II): prophylactic HPV vaccination, current knowledge, practical procedures and new issues].

    Science.gov (United States)

    Monsonego, Joseph

    2007-04-01

    Despite the considerable success of early screening for prevention of cervical cancer, Pap smears have not fulfilled the hopes that it would lead to a large-scale reduction of this cancer's incidence. Screening appears to be useful for a tiny portion of the world population, although a relatively large portion must put up with its limitations and disadvantages. Human papilloma viruses (HPV) 16 and 18 are responsible for two thirds of all cervical cancers worldwide. The condylomata (condyloma acuminatum), or genital warts, induced by HPV 6 and 11 are frequent among the young and difficult to manage. The extent and burden of HPV infection are considerable, as is the psychological and emotional impact of the diseases associated with it. Because cancer of the cervix is the final consequence of chronic HPV infection, it can be prevented by vaccination. A prophylactic vaccine to protect against the precancerous and cancerous lesions associated with HPV should save lives, reduce expensive diagnostic and therapeutic interventions, and have substantial individual and collective benefits. Clinical trials of anti-HPV vaccines for the prevention of cervical cancer and condyloma have shown remarkable results and an efficacy unequaled in the history of vaccination against infectious diseases. Vaccine efficacy has been shown only in young girls never exposed to the virus and only for the lesions associated with the specific viral types in the vaccine. Preliminary data indicate that the vaccination is effective in women who have previously eliminated naturally the virus. It has no therapeutic effects on existing lesions or in healthy virus carriers. Practical questions remain to be resolved. If the vaccination is left to individual initiative and vaccination coverage is insufficient, there will be no perceptible reduction in the frequency of cervical cancer. Vaccination policies will not be identical in poor countries, where the disease represents one of the leading causes of

  20. Current state of knowledge in microbial degradation of polycyclic aromatic hydrocarbons (PAHs: a review

    Directory of Open Access Journals (Sweden)

    Debajyoti Ghosal

    2016-08-01

    PAHs. The main purpose of this review is to provide an overview of current knowledge of bacteria, halophilic archaea, fungi and algae mediated degradation/transformation of PAHs. In addition, factors affecting PAHs degradation in the environment, recent advancement in genetic, genomic, proteomic and metabolomic techniques are also highlighted with an aim to facilitate the development of a new insight into the bioremediation of PAH in the environment.

  1. Biochemical regulation of airway smooth muscle tone: current knowledge and therapeutic implications.

    Science.gov (United States)

    Torphy, T J

    1987-01-01

    advantage will be gained by developing new beta-adrenoceptor agonists. The task of developing novel bronchodilators will be facilitated by an understanding at the molecular level of the diversity among smooth muscles and the processes that regulate smooth muscle tone. Hopefully, such knowledge will lead to a new generation of highly effective, tissue-selective bronchodilators with significant therapeutic advantages over those currently available.

  2. Skin Wound Healing: An Update on the Current Knowledge and Concepts.

    Science.gov (United States)

    Sorg, Heiko; Tilkorn, Daniel J; Hager, Stephan; Hauser, Jörg; Mirastschijski, Ursula

    2017-01-01

    repair have been delineated in part, many underlying pathophysiological processes are still unknown. The purpose of the following update on skin wound healing is to focus on the different phases and to brief the reader on the current knowledge and new insights. Skin wound healing is a complex process, which is dependent on many cell types and mediators interacting in a highly sophisticated temporal sequence. Although some interactions during the healing process are crucial, redundancy is high and other cells or mediators can adopt functions or signaling without major complications. © 2016 S. Karger AG, Basel.

  3. Clinical and epidemiological aspects of cardiomyopathies: a critical review of current knowledge.

    Science.gov (United States)

    Sangiorgi, Mario

    2003-02-01

    unknown origin, familial forms of a genetic origin, depending on alterations of contractile or regulating functional proteins, when myocardial injury is the sole manifestation (idiopathic) of clinical picture. The most modern etiopathogenetic, pathophysiological, and clinical features of each form of CM are briefly described in order to suggest a complete definition of the disease and to state a clinical-epidemiological setting that encompasses the current knowledge.

  4. Delivering "Just-In-Time" Smoking Cessation Support Via Mobile Phones: Current Knowledge and Future Directions.

    Science.gov (United States)

    Naughton, Felix

    2016-05-28

    Smoking lapses early on during a quit attempt are highly predictive of failing to quit. A large proportion of these lapses are driven by cravings brought about by situational and environmental cues. Use of cognitive-behavioral lapse prevention strategies to combat cue-induced cravings is associated with a reduced risk of lapse, but evidence is lacking in how these strategies can be effectively promoted. Unlike most traditional methods of delivering behavioral support, mobile phones can in principle deliver automated support, including lapse prevention strategy recommendations, Just-In-Time (JIT) for when a smoker is most vulnerable, and prevent early lapse. JIT support can be activated by smokers themselves (user-triggered), by prespecified rules (server-triggered) or through sensors that dynamically monitor a smoker's context and trigger support when a high risk environment is sensed (context-triggered), also known as a Just-In-Time Adaptive Intervention (JITAI). However, research suggests that user-triggered JIT cessation support is seldom used and existing server-triggered JIT support is likely to lack sufficient accuracy to effectively target high-risk situations in real time. Evaluations of mobile phone cessation interventions that include user and/or server-triggered JIT support have yet to adequately assess whether this improves management of high risk situations. While context-triggered systems have the greatest potential to deliver JIT support, there are, as yet, no impact evaluations of such systems. Although it may soon be feasible to learn about and monitor a smoker's context unobtrusively using their smartphone without burdensome data entry, there are several potential advantages to involving the smoker in data collection. This commentary describes the current knowledge on the potential for mobile phones to deliver automated support to help smokers manage or cope with high risk environments or situations for smoking, known as JIT support. The article

  5. Current State of Knowledge in Microbial Degradation of Polycyclic Aromatic Hydrocarbons (PAHs): A Review

    Science.gov (United States)

    Ghosal, Debajyoti; Ghosh, Shreya; Dutta, Tapan K.; Ahn, Youngho

    2016-01-01

    purpose of this review is to provide an overview of current knowledge of bacteria, halophilic archaea, fungi and algae mediated degradation/transformation of PAHs. In addition, factors affecting PAHs degradation in the environment, recent advancement in genetic, genomic, proteomic and metabolomic techniques are also highlighted with an aim to facilitate the development of a new insight into the bioremediation of PAH in the environment. PMID:27630626

  6. Application of current knowledge and trends in sports training of top level volleyball teams in the Czech Republic

    OpenAIRE

    Michal Lehnert; Jiří Stierand; František Chmelík; Zdeněk Haník

    2010-01-01

    BACKGROUND: To achieve the best results in top volleyball it is necessary to analyze the current state and to react adequately to development trends, which characterize modern volleyball. OBJECTIVES: The goal of the study was to acquire information regarding how do top volleyball coaches of senior and junior volleyball teams in the Czech Republic put current knowledge and trends in volleyball sport training and coaching in practice. METHODS: We created a survey consisting of 31 questions, whi...

  7. Ischaemic preconditioning - Current knowledge and potential future applications after 30 years of experience.

    Science.gov (United States)

    Stokfisz, Karolina; Ledakowicz-Polak, Anna; Zagorski, Maciej; Zielinska, Marzenna

    2017-05-13

    Ischaemic preconditioning (IPC) phenomenon has been known for thirty years. During that time several studies showed that IPC provided by brief ischaemic and reperfusion episodes prior to longer ischaemia can bestow a protective effect to both preconditioned and also remote organs. IPC affecting remote organs is called remote ischaemic preconditioning. Initially, most IPC studies were focused on enhancing myocardial resistance to subsequent ischaemia and reperfusion injury. However, preconditioning was found to be a universal phenomenon and was observed in various organs and tissues including the heart, liver, brain, retina, kidney, skeletal muscles and intestine. Currently, there are a lot of simultaneous studies are underway aiming at finding out whether IPC can be helpful in protecting these organs. The mechanism of local and remote IPC is complex and not well known. Several triggers, intracellular pathways and effectors, humoral, neural and induced by genetic changes may be considered potential pathways in the protective activity of local and remote IPC. Local and remote IPC mechanism may potentially serve as heart protection during cardiac surgery and may limit the infarct size of the myocardium, can be a strategy for preventing the development of acute kidney injury development and liver damage during transplantation, may protect the brain against ischaemic injury. In addition, the method is safe, non-invasive, cheap and easily applicable. The main purpose of this review article is to present new advances which would help to understand the potential mechanism of IPC. It also discusses both its potential applications and utility in clinical settings. Copyright © 2017 Medical University of Bialystok. Published by Elsevier B.V. All rights reserved.

  8. Reducing Uncertainty for Acute Febrile Illness in Resource-Limited Settings: The Current Diagnostic Landscape.

    Science.gov (United States)

    Robinson, Matthew L; Manabe, Yukari C

    2017-06-01

    AbstractDiagnosing the cause of acute febrile illness in resource-limited settings is important-to give the correct antimicrobials to patients who need them, to prevent unnecessary antimicrobial use, to detect emerging infectious diseases early, and to guide vaccine deployment. A variety of approaches are yielding more rapid and accurate tests that can detect more pathogens in a wider variety of settings. After decades of slow progress in diagnostics for acute febrile illness in resource-limited settings, a wave of converging advancements will enable clinicians in resource-limited settings to reduce uncertainty for the diagnosis of acute febrile illness.

  9. On Mattering: A Coal Ash Flood and the Limits of Environmental Knowledge

    Directory of Open Access Journals (Sweden)

    Hatmaker, Susie

    2014-05-01

    Full Text Available This paper investigates the largest flood of coal ash in United States history as an event at once monumental and insignificant. It traces affective forces generative of both the ash, and its invisibility. In the moment of rupture, the ash flowed out of a large holding pond in a spill of layered sediments – each layer of particulate a temporary resting place for a forceful trajectory of matter spurned into motion elsewhere in space and time. This paper takes up the atemporal matter of this coal ash flood to ask: out of what movements and connections was the ash formed? How did this particular landscape change to accommodate its accumulation? What trajectories flowed into the pond, and what hidden memories sat buried in its mass? Drawing on ethnographic and archival research, this paper weaves together juxtaposed scenes that form (some of the backstory of this event, and invites a reconsideration of the practices of knowledge that helped condition it.

  10. Investigating Relationships among Pre-Service Science Teachers' Conceptual Knowledge of Electric Current, Motivational Beliefs and Self-Regulation

    Science.gov (United States)

    Inaltun, Hüseyin; Ates, Salih

    2015-01-01

    The purpose of this study is to examine relationships among pre-service science teachers' conceptual knowledge of electric current, motivational beliefs, and self-regulation. One hundred and twenty-seven students (female = 107, male = 20) enrolled in the science education program of a public university in Ankara participated the study. A concept…

  11. Simulation of electrical and thermal behavior of high temperature superconducting fault current limiting transformer (HTc-SFCLT)

    Energy Technology Data Exchange (ETDEWEB)

    Kurupakorn, C [Department of Electrical Engineering and Computer Science, Nagoya University, Nagoya 464-8603 (Japan); Kojima, H [EcoTopia Science Institute, Nagoya University, Nagoya 464-8603 (Japan); Hayakawa, N [Department of Electrical Engineering and Computer Science, Nagoya University, Nagoya 464-8603 (Japan); Endo, F [EcoTopia Science Institute, Nagoya University, Nagoya 464-8603 (Japan); Kashima, N [Chubu Electric Power Co., Inc., Nagoya 459-8522 (Japan); Nagaya, S [Chubu Electric Power Co., Inc., Nagoya 459-8522 (Japan); Noe, M [Forschungszentrum Karlsruhe, Karlsruhe D-76021 (Germany); Okubo, H [EcoTopia Science Institute, Nagoya University, Nagoya 464-8603 (Japan)

    2006-06-01

    Superconducting Fault Current Limiting Transformer (SFCLT) is expected to perform functions both of transformer in the normal operating condition and of fault current limiter in the system fault condition. As the Phase-3 of the SFCLT project, we have been developing SFCLT based on Bi2212/CuNi bulk coils at LN{sub 2} temperature and verified its technical feasibility. In this paper, we developed a numerical model for evaluation of the electrical and thermal behavior of HTc-SFCLT such as current limitation and recovery characteristics. This model took into account E-J characteristics of Bi2212/CuNi bulk coil and its electrical and thermal transient phenomena during the operation of HTc-SFCLT. The simulated current agreed well with the experimental data with the error of less than 5%. The excellent current limitation and self recovery characteristics obtained by the experiments could also be reproduced. With the numerical model, current and thermal behavior of HTc-SFCLT was simulated for different parameters of conductor configuration, which would be useful for the future design and optimization of HTc-SFCLT.

  12. Design and optimization of LCL-VSC grid-tied converter having short circuit fault current limiting ability

    Science.gov (United States)

    Liu, Mengqi; Liu, Haijun; Wang, Zhikai

    2017-01-01

    Traditional LCL grid-tied converters haven't the ability to limit the short-circuit fault current and only remove grid-connected converter using the breaker. However, the VSC converters become uncontrollable after the short circuit fault cutting off and the power switches may be damaged if the circuit breaker removes slowly. Compared to the filter function of the LCL passive components in traditional VSC converters, the novel LCL-VSC converter has the ability of limiting the short circuit fault current using the reasonable designed LCL parameters. In this paper the mathematical model of the LCL converter is established and the characteristics of the short circuit fault current generated by the ac side and dc side are analyzed. Thus one design and optimization scheme of the reasonable LCL passive parameter is proposed for the LCL-VSC converter having short circuit fault current limiting ability. In addition to ensuring the LCL passive components filtering the high-frequency harmonic, this scheme also considers the impedance characteristics to limit the fault current of AC and DC short circuit fault respectively flowing through the power switch no more than the maximum allowable operating current, in order to make the LCL converter working continuously. Finally, the 200kW simulation system is set up to prove the validity and feasibility of the theoretical analysis using the proposed design and optimization scheme.

  13. Non-axisymmetric equilibrium reconstruction and suppression of density limit disruptions in a current-carrying stellarator

    Science.gov (United States)

    Ma, Xinxing; Ennis, D. A.; Hanson, J. D.; Hartwell, G. J.; Knowlton, S. F.; Maurer, D. A.

    2017-10-01

    Non-axisymmetric equilibrium reconstructions have been routinely performed with the V3FIT code in the Compact Toroidal Hybrid (CTH), a stellarator/tokamak hybrid. In addition to 50 external magnetic measurements, 160 SXR emissivity measurements are incorporated into V3FIT to reconstruct the magnetic flux surface geometry and infer the current distribution within the plasma. Improved reconstructions of current and q profiles provide insight into understanding the physics of density limit disruptions observed in current-carrying discharges in CTH. It is confirmed that the final scenario of the density limit of CTH plasmas is consistent with classic observations in tokamaks: current profile shrinkage leads to growing MHD instabilities (tearing modes) followed by a loss of MHD equilibrium. It is also observed that the density limit at a given current linearly increases with increasing amounts of 3D shaping fields. Consequently, plasmas with densities up to two times the Greenwald limit are attained. Equilibrium reconstructions show that addition of 3D fields effectively moves resonance surfaces towards the edge of the plasma where the current profile gradient is less, providing a stabilizing effect. This work is supported by US Department of Energy Grant No. DE-FG02-00ER54610.

  14. Content knowledge development in a chemistry teacher preparation program: A current potentials and challenges

    Science.gov (United States)

    Widhiyanti, Tuszie; Treagust, David F.; Mocerino, Mauro; Vishnumolakala, Venkat

    2017-08-01

    One of the essential facets in teacher education program is the development of the teachers' content knowledge and it has been suggested by many scholars that the study to analyse the process of content knowledge development in teacher education program is necessary. Regarding this, the aim of this research is to evaluate the existing program of developing pre-service chemistry teachers' content knowledge, especially in the topic about the particulate nature of matter. The curriculum of content knowledge development was analysed using the forms of the curriculum evaluation (Akker, 1998; Goodlad, Klein, and Tye (1979); Treagust, 1987). Within this framework, the curriculum was evaluated in several aspects including the vision and intention of the curriculum as mentioned in the curriculum documents (intended curriculum), the users' interpretation and perception about the curriculum (perceived curriculum), the actual process of curriculum implementation (implemented curriculum), and the outcomes of the curriculum (achieved curriculum). According to the framework used for this study, the research combined qualitative and quantitative methods of data collection and the interpretation including document analysis, classroom observation, interviews, and two-tier diagnostic test. Through this research we examined the coherence among those aspects. The results reveal that although the content knowledge development is explicitly intended in a curriculum, its implementation and lecturers' perceptions give influence in the results as appear in pre-service teachers' achievements. In general, this research provides basic information about the effectiveness of the program including the challenges and the potentials for a reconsideration of the program in the future.

  15. The Limitations of Upper-Atmosphere Research Vehicles Powered by Current British Solid-Fuel Rockets

    National Research Council Canada - National Science Library

    King-Hele, D. G

    1953-01-01

    .... If current rockets are to be of value in upper-atmosphere research, therefore, they must either be used in a single-stage arrangement, or be launched well above sea level, perhaps from a balloon or mountain top...

  16. Parasites of importance for human health in Nigerian dogs: high prevalence and limited knowledge of pet owners.

    Science.gov (United States)

    Ugbomoiko, Uade Samuel; Ariza, Liana; Heukelbach, Jorg

    2008-12-09

    Dogs are the most common pet animals worldwide. They may harbour a wide range of parasites with zoonotic potential, thus causing a health risk to humans. In Nigeria, epidemiological knowledge on these parasites is limited. In a community-based study, we examined 396 dogs in urban and rural areas of Ilorin (Kwara State, Central Nigeria) for ectoparasites and intestinal helminths. In addition, a questionnaire regarding knowledge and practices was applied to pet owners. Nine ectoparasite species belonging to four taxa and six intestinal helminth species were identified: fleas (Ctenocephalides canis, Pulex irritans, Tunga penetrans), mites (Demodex canis, Otodectes sp., Sarcoptes scabiei var. canis), ticks (Rhipicephalus sanguineus, Ixodes sp.), and lice (Trichodectes canis); and Toxocara canis, Ancylostoma sp., Trichuris vulpis, Dipylidium caninum, Taenidae and Strongyloides sp. Overall prevalence of ectoparasites was 60.4% and of intestinal helminths 68.4%. The occurrence of C. canis, R. sanguineus, T. canis, Ancylostoma sp. and T. vulpis was most common (prevalence 14.4% to 41.7%). Prevalence patterns in helminths were age-dependent, with T. canis showing a decreasing prevalence with age of host, and a reverse trend in other parasite species. Knowledge regarding zoonoses was very limited and the diseases not considered a major health problem. Treatment with antiparasitic drugs was more frequent in urban areas. Parasites of importance for human health were highly prevalent in Nigerian dogs. Interventions should include health education provided to dog owners and the establishment of a program focusing on zoonotic diseases.

  17. The Effect of Current-Limiting Reactors on the Tripping of Short Circuits in High-Voltage Electrical Equipment

    Energy Technology Data Exchange (ETDEWEB)

    Volkov, M. S.; Gusev, Yu. P., E-mail: GusevYP@mpei.ru; Monakov, Yu. V.; Cho, Gvan Chun [National Research University “Moscow Power Engineering Institute,” (Russian Federation)

    2016-01-15

    The insertion of current-limiting reactors into electrical equipment operating at a voltage of 110 and 220 kV produces a change in the parameters of the transient recovery voltages at the contacts of the circuit breakers for disconnecting short circuits, which could be the reason for the increase in the duration of the short circuit, damage to the electrical equipment and losses in the power system. The results of mathematical modeling of the transients, caused by tripping of the short circuit in a reactive electric power transmission line are presented, and data are given on the negative effect of a current-limiting resistor on the rate of increase and peak value of the transient recovery voltages. Methods of ensuring the standard requirements imposed on the parameters of the transient recovery voltages when using current-limiting reactors in the high-voltage electrical equipment of power plants and substations are proposed and analyzed.

  18. Malassezia: Estado del conocimiento y perspectivas en su estudio Malassezia: Current knowledge and study perspectives

    Directory of Open Access Journals (Sweden)

    Gustavo E. Giusiano

    2006-03-01

    knowledge of the ecology and epidemiology of this genus. Noteworthy antifungal susceptibility variations have been observed in some species, although there is not a standard method for these yeasts. There are few data about their biochemical characteristics, and the enzymes they produce might be important virulence factors, favouring host tissue invasion. Malassezia has been recognised as a member of the normal human and animal skin. Its implication in pathologic processes, including skin diseases to systemic infections, is the main issue in current investigations in order to determine the real pathogenic role of these yeasts.

  19. The Unsaid, the Unheard, the Unseen in Ethnography: The Political Limit of the Knowledge

    Directory of Open Access Journals (Sweden)

    Alessandro Deiana

    2015-07-01

    Full Text Available L'articolo sviluppa il tema della frontiera sensoriale come limite politico con il quale l'etnografo si trova a fare i conti quando l'accesso alla sfera esperienziale dei soggetti che intende studiare comporta dilemmi etici. In particolare affronta la possibilità che il sapere etnografico non sempre debba essere inteso come superamento dei limiti dati per apportare nuovi contributi alla conoscenza, ma semmai come diserzione epistemologica di fronte al rischio di farsi strumento sia di ciò che normalmente si osteggia, sia di un dispositivo conoscitivo funzionale alla tassonomia sociale dominante. Per illustrare quest'ipotesi viene preso in considerazione il filone di ricerca etnografica sui temi sensibili e in particolare verranno discusse criticamente delle ricerche su organizzazioni fasciste e razziste.

  20. Feed Efficiency: An Assessment of Current Knowledge from a Voluntary Subsample of the Swine Industry

    Science.gov (United States)

    Flohr, Josh R.; Tokach, Mike D.; DeRouchey, Joel M.; Goodband, Robert D.; Dritz, Steve S.; Nelssen, Jim L.; Patience, John F.

    2014-01-01

    A voluntary sample of pork producers and advisers to the swine industry were surveyed about feed efficiency. The questionnaire was designed to accomplish three objectives: (a) determine the level of knowledge related to feed efficiency topics, (b) identify production practices used that influence feed efficiency, and (c) identify information gaps…

  1. A Case Analysis to Increase Awareness of Current USMC Knowledge Management (KM) Practices

    Science.gov (United States)

    2013-09-01

    cliché for centuries. Descartes ’ cogito ergo sum (I think, therefore I am) is also a cliché, and also a phrase for traditional epistemology. Knowledge...manage what they know. Watertown, MA: Harvard Business School Press. Descartes , R. (1644). Principles of philosophy. Translated by Miller, V. R

  2. Technical Study on Improvement of Endurance Capability of Limit Short-circuit Current of Charge Control SMART Meter

    Science.gov (United States)

    Li, W. W.; Du, Z. Z.; Yuan, R. m.; Xiong, D. Z.; Shi, E. W.; Lu, G. N.; Dai, Z. Y.; Chen, X. Q.; Jiang, Z. Y.; Lv, Y. G.

    2017-10-01

    Smart meter represents the development direction of energy-saving smart grid in the future. The load switch, one of the core parts of smart meter, should be of high reliability, safety and endurance capability of limit short-circuit current. For this reason, this paper discusses the quick simulation of relationship between attraction and counterforce of load switch without iteration, establishes dual response surface model of attraction and counterforce and optimizes the design scheme of load switch for charge control smart meter, thus increasing electromagnetic attraction and spring counterforce. In this way, this paper puts forward a method to improve the withstand capacity of limit short-circuit current.

  3. Climate Analogues Suggest Limited Potential for Intensification of Production on Current Croplands Under Climate Change

    Science.gov (United States)

    Pugh, T. A. M.; Mueller, C.; Elliott, J.; Deryng, D.; Folberth, C.; Olin, S.; Schmid, E.; Arneth, A.

    2016-01-01

    Climate change could pose a major challenge to efforts towards strongly increase food production over the coming decades. However, model simulations of future climate-impacts on crop yields differ substantially in the magnitude and even direction of the projected change. Combining observations of current maximum-attainable yield with climate analogues, we provide a complementary method of assessing the effect of climate change on crop yields. Strong reductions in attainable yields of major cereal crops are found across a large fraction of current cropland by 2050. These areas are vulnerable to climate change and have greatly reduced opportunity for agricultural intensification. However, the total land area, including regions not currently used for crops, climatically suitable for high attainable yields of maize, wheat and rice is similar by 2050 to the present-day. Large shifts in land-use patterns and crop choice will likely be necessary to sustain production growth rates and keep pace with demand.

  4. Status and Progress of a Fault Current Limiting Hts Cable to BE Installed in the con EDISON Grid

    Science.gov (United States)

    Maguire, J.; Folts, D.; Yuan, J.; Henderson, N.; Lindsay, D.; Knoll, D.; Rey, C.; Duckworth, R.; Gouge, M.; Wolff, Z.; Kurtz, S.

    2010-04-01

    In the last decade, significant advances in the performance of second generation (2G) high temperature superconducting wire have made it suitable for commercially viable applications such as electric power cables and fault current limiters. Currently, the U.S. Department of Homeland Security is co-funding the design, development and demonstration of an inherently fault current limiting HTS cable under the Hydra project with American Superconductor and Consolidated Edison. The cable will be approximately 300 m long and is being designed to carry 96 MVA at a distribution level voltage of 13.8 kV. The underground cable will be installed and energized in New York City. The project is led by American Superconductor teamed with Con Edison, Ultera (Southwire and nkt cables joint venture), and Air Liquide. This paper describes the general goals, design criteria, status and progress of the project. Fault current limiting has already been demonstrated in 3 m prototype cables, and test results on a 25 m three-phase cable will be presented. An overview of the concept of a fault current limiting cable and the system advantages of this unique type of cable will be described.

  5. Limited Resources for Self-Regulation : A Current Overview of the Strength Model

    NARCIS (Netherlands)

    Baumeister, R. F.

    2016-01-01

    This chapter provides an overview of my efforts to develop a new model of self-regulation over the past 25. years. The strength model sees self-regulation as dependent on a limited energy resource, and self-regulatory capacity functions like a physical muscle: It seems to get tired after use, it

  6. Space-charge-limited hole current in poly(9,9-dioctylfluorene) diodes

    NARCIS (Netherlands)

    Nicolai, H. T.; Wetzelaer, G. A. H.; Kuik, M.; Kronemeijer, A. J.; de Boer, B.; Blom, P. W. M.

    2010-01-01

    Characterization of the hole transport in blue-emitting polymers as poly(9,9-dioctylfluorene) (PFO) is strongly hindered by their large ionization potential of similar to 6 eV. Using common anodes as poly(3,4-ethylenedioxythiophene)/poly(styrenesulphonic acid) leads to a strongly injection limited

  7. Current strategies for improving access and adherence to antiretroviral therapies in resource-limited settings

    Directory of Open Access Journals (Sweden)

    Scanlon ML

    2013-01-01

    Full Text Available Michael L Scanlon,1,2 Rachel C Vreeman1,21Department of Pediatrics, Indiana University School of Medicine, Indianapolis, IN, USA; 2USAID, Academic Model Providing Access to Healthcare (AMPATH Partnership, Eldoret, KenyaAbstract: The rollout of antiretroviral therapy (ART significantly reduced human immunodeficiency virus (HIV-related morbidity and mortality, but good clinical outcomes depend on access and adherence to treatment. In resource-limited settings, where over 90% of the world’s HIV-infected population resides, data on barriers to treatment are emerging that contribute to low rates of uptake in HIV testing, linkage to and retention in HIV care systems, and suboptimal adherence rates to therapy. A review of the literature reveals limited evidence to inform strategies to improve access and adherence with the majority of studies from sub-Saharan Africa. Data from observational studies and randomized controlled trials support home-based, mobile and antenatal care HIV testing, task-shifting from doctor-based to nurse-based and lower level provider care, and adherence support through education, counseling and mobile phone messaging services. Strategies with more limited evidence include targeted HIV testing for couples and family members of ART patients, decentralization of HIV care, including through home- and community-based ART programs, and adherence promotion through peer health workers, treatment supporters, and directly observed therapy. There is little evidence for improving access and adherence among vulnerable groups such as women, children and adolescents, and other high-risk populations and for addressing major barriers. Overall, studies are few in number and suffer from methodological issues. Recommendations for further research include health information technology, social-level factors like HIV stigma, and new research directions in cost-effectiveness, operations, and implementation. Findings from this review make a

  8. Case Study of Rip Current Knowledge amongst Students Participating in a Study Abroad Program

    Science.gov (United States)

    Houser, Chris; Brander, Robert; Brannstrom, Christian; Trimble, Sarah; Flaherty, Jane

    2016-01-01

    Rip currents are narrow seaward-flowing currents common on many global beaches and are capable of transporting even experienced swimmers a significant distance offshore, placing them at risk of needing rescue or drowning. In this respect, rips represent a significant hazard to beach users around the world and are recognized as a major health…

  9. Racial/ethnic differences in electronic cigarette knowledge, social norms, and risk perceptions among current and former smokers.

    Science.gov (United States)

    Webb Hooper, Monica; Kolar, Stephanie K

    2017-04-01

    Psychosocial factors that may affect electronic cigarette (e-cigarette) initiation or maintenance among racial/ethnic minorities are not well-understood. This study examined racial/ethnic differences in e-cigarette knowledge, risk perceptions, and social norms among current and former smokers. Individuals with a tobacco smoking history and an awareness of e-cigarettes (N=285) were recruited from the community from June to August 2014. Telephone-administered surveys assessed demographics, smoking status, and e-cigarette knowledge, risk perceptions, and normative beliefs. Analyses of covariance and multinomial logistic regression tested associations by race/ethnicity. Controlling for sociodemographics and smoking status, White participants scored significantly higher on e-cigarette knowledge, compared to both Hispanics and African Americans/Blacks. Knowledge was lower among African Americans/Blacks compared to Hispanics. Compared to both Whites and Hispanics, African American/Black participants held lower perceptions regarding e-cigarette health risks and were less likely to view e-cigarettes as addictive. Normative beliefs did not differ by race/ethnicity. In conclusion, e-cigarette knowledge, health risk perceptions, and perceived addictiveness differed by race/ethnicity. The variation in e-cigarette knowledge and beliefs among smokers and former smokers has implications for use, and potentially, dual use. Understanding these relationships in unrepresented populations can inform future research and practice. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Estimation of the spatial distribution of traps using space-charge-limited current measurements in an organic single crystal

    KAUST Repository

    Dacuña, Javier

    2012-09-06

    We used a mobility edge transport model and solved the drift-diffusion equation to characterize the space-charge-limited current of a rubrene single-crystal hole-only diode. The current-voltage characteristics suggest that current is injection-limited at high voltage when holes are injected from the bottom contact (reverse bias). In contrast, the low-voltage regime shows that the current is higher when holes are injected from the bottom contact as compared to hole injection from the top contact (forward bias), which does not exhibit injection-limited current in the measured voltage range. This behavior is attributed to an asymmetric distribution of trap states in the semiconductor, specifically, a distribution of traps located near the top contact. Accounting for a localized trap distribution near the contact allows us to reproduce the temperature-dependent current-voltage characteristics in forward and reverse bias simultaneously, i.e., with a single set of model parameters. We estimated that the local trap distribution contains 1.19×1011 cm -2 states and decays as exp(-x/32.3nm) away from the semiconductor-contact interface. The local trap distribution near one contact mainly affects injection from the same contact, hence breaking the symmetry in the charge transport. The model also provides information of the band mobility, energy barrier at the contacts, and bulk trap distribution with their corresponding confidence intervals. © 2012 American Physical Society.

  11. Current status data with competing risks : Limiting distribution of the MLE

    NARCIS (Netherlands)

    Groeneboom, P.; Maathuis, M.H.; Wellner, J.A.

    2008-01-01

    We study nonparametric estimation for current status data with competing risks. Our main interest is in the nonparametric maximum likelihood estimator (MLE), and for comparison we also consider a simpler “naive estimator.” Groeneboom, Maathuis and Wellner [Ann. Statist. (2008) 36 1031–1063] proved

  12. Prehospital Stroke Care : Limitations of Current Interventions and Focus on New Developments

    NARCIS (Netherlands)

    Yperzeele, Laetitia; Van Hooff, Robbert-Jan; De Smedt, Ann; Espinoza, Alexis Valenzuela; de Casseye, Rohny Van; Hubloue, Ives; De Keyser, Jacques; Brouns, Raf

    Background: The global burden of stroke is immense, both in medical and economic terms. With the aging population and the ongoing industrialization of the third world, stroke prevalence is expected to increase and will have a major effect on national health expenditures. Currently, the medical

  13. Geothermal projects funded under the NER 300 programme - current state of development and knowledge gained

    Science.gov (United States)

    Shortall, Ruth; Uihlein, Andreas

    2017-04-01

    Introduction The NER 300 programme, managed by the European Commission is one of the largest funding programmes for innovative low-carbon energy demonstration projects. NER 300 is so called because it is funded from the sale of 300 million emission allowances from the new entrants' reserve (NER) set up for the third phase of the EU emissions trading system (ETS). The programme aims to successfully demonstrate environmentally safe carbon capture and storage (CCS) and innovative renewable energy (RES) technologies on a commercial scale with a view to scaling up production of low-carbon technologies in the EU. Consequently, it supports a wide range of CCS and RES technologies (bioenergy, concentrated solar power, photovoltaics, geothermal, wind, ocean, hydropower, and smart grids). Funded projects and the role of geothermal projects for the programme In total, about EUR 2.1 billion have been awarded through the programme's 2 calls for proposals (the first awarded in December 2012, the second in July 2014). The programme has awarded around EUR 70 million funding to 3 geothermal projects in Hungary, Croatia and France. The Croatian geothermal project will enter into operation during 2017 the Hungarian in 2018, and the French in 2020. Knowledge Sharing Knowledge sharing requirements are built into the legal basis of the programme as a critical tool to lower risks in bridging the transition to large-scale production of innovative renewable energy and CCS deployment. Projects have to submit annually to the European Commission relevant knowledge gained during that year in the implementation of their project. The relevant knowledge is aggregated and disseminated by the European Commission to industry, research, government, NGO and other interest groups and associations in order to provide a better understanding of the practical challenges that arise in the important step of scaling up technologies and operating them at commercial scale. The knowledge sharing of the NER 300

  14. Effects of biodiversity on ecosystem functioning: a consensus of current knowledge

    Science.gov (United States)

    Hooper, D.U.; Chapin, F. S.; Ewel, J.J.; Hector, A.; Inchausti, P.; Lavorel, S.; Lawton, J.H.; Lodge, D.M.; Loreau, M.; Naeem, S.; Schmid, B.; SetSlS, H.; Symstad, A.J.; Vandermeer, J.; Wardle, D.A.

    2005-01-01

    Humans are altering the composition of biological communities through a variety of activities that increase rates of species invasions and species extinctions, at all scales, from local to global. These changes in components of the Earth's biodiversity cause concern for ethical and aesthetic reasons, but they also have a strong potential to alter ecosystem properties and the goods and services they provide to humanity. Ecological experiments, observations, and theoretical developments show that ecosystem properties depend greatly on biodiversity in terms of the functional characteristics of organisms present in the ecosystem and the distribution and abundance of those organisms over space and time. Species effects act in concert with the effects of climate, resource availability, and disturbance regimes in influencing ecosystem properties. Human activities can modify all of the above factors; here we focus on modification of these biotic controls.The scientific community has come to a broad consensus on many aspects of the relationship between biodiversity and ecosystem functioning, including many points relevant to management of ecosystems. Further progress will require integration of knowledge about biotic and abiotic controls on ecosystem properties, how ecological communities are structured, and the forces driving species extinctions and invasions. To strengthen links to policy and management, we also need to integrate our ecological knowledge with understanding of the social and economic constraints of potential management practices. Understanding this complexity, while taking strong steps to minimize current losses of species, is necessary for responsible management of Earth's ecosystems and the diverse biota they contain.Based on our review of the scientific literature, we are certain of the following conclusions:1) Species' functional characteristics strongly influence ecosystem properties. Functional characteristics operate in a variety of contexts

  15. Application of current knowledge and trends in sports training of top level volleyball teams in the Czech Republic

    Directory of Open Access Journals (Sweden)

    Michal Lehnert

    2010-01-01

    Full Text Available BACKGROUND: To achieve the best results in top volleyball it is necessary to analyze the current state and to react adequately to development trends, which characterize modern volleyball. OBJECTIVES: The goal of the study was to acquire information regarding how do top volleyball coaches of senior and junior volleyball teams in the Czech Republic put current knowledge and trends in volleyball sport training and coaching in practice. METHODS: We created a survey consisting of 31 questions, which were divided into 5 areas: respecting of the current requirements of game performance in training, training efficiency, conditioning, coaching and psycho-social aspects. The survey was sent to 49 coaches, 24 of them replied (response rate 49 %. RESULTS: The research shows that coaches do not apply all important knowledge and trends for players' preparation (76 % of correct answers in total. Groups of coaches were further divided to subgroups according to gender of the trained teams, age categories, coaches work load and 1st and 2nd class coaches. The comparison of the answers in the subgroup of coaches with respect to segregated areas has only pointed at a difference between male and female teams in the area of psycho-social training aspects (Z = 1.756; p = 0.079; d = 0.717. The comparison of coaches' groups answers to individual questions show that: a coaches of male teams base their training sessions on real game situations and choose the content of the exercises with the ball more thoroughly (Z = 1.85; p = 0.07; d = 0.75 and require defensive game combinations at the net more often (Z = 1.81; p = 0.07; d = 0.74; b junior teams are behind (Z = 1.90; p = 0.06; d = 0.77 senior teams in the number of training hours with the ball a week and in making conditions for successful realization of offensive game combinations with fast set (Z = 2.10; p = 0.04; d = 0.86; c 1st class coaches within the scope of condition training pay more attention to core training

  16. Is tourism damaging ecosystems in the Andes? Current knowledge and an agenda for future research

    National Research Council Canada - National Science Library

    Barros, Agustina; Monz, Christopher; Pickering, Catherine

    2015-01-01

    Despite the popularity of tourism and recreation in the Andes in South America and the regions conservation value, there is limited research on the ecological impacts of these types of anthropogenic use...

  17. Analysis of the Processes of Short-Currents Limiting by Transformer with High-Temperature Superconducting Windings

    Directory of Open Access Journals (Sweden)

    Manusov V.Z.

    2017-04-01

    Full Text Available An important advantage of transformers with high-temperature superconducting winding is their ability to limit the short-circuit currents. The article discusses a physico-mathematical model that analyses transient processes at short-circuit currents in electrical networks containing transformers with a high-temperature superconducting winding. One of the main ideas and objectives of this work is to investigate the process of short-circuit currents limiting by means of a transformer with a high-temperature superconductor winding, which makes it possible to combine two series-connected elements in one device: transformer and a reactor. The effectiveness of this method is due to the fact that when the short-circuit currents exceed the critical value of the temperature of the superconductor winding, it goes to the normal state with high winding resistance for short-circuit currents. It is important to know when a superconductor should go over to a normal state with the loss of superconductivity. For this purpose, a program was developed to determine the amount of heat generated by a short-circuit current flowing before it is disconnected. For a transformer with high-temperature superconducting winding with a capacity of 40 MVA, a short circuit must be eliminated after 0.1 seconds, without switching off the transformer. To limit the short-circuit current; it is intended to use a hybrid winding. The performed assessment showed that the return of the winding to the superconducting state, first, depends on the ratio of the short-circuit currents to the operating current. This is the criterion for the return/non-return to the superconducting state.

  18. How Do Clinicians Learn About Knowledge Translation? An Investigation of Current Web-Based Learning Opportunities

    OpenAIRE

    Damarell, Raechel A; Tieman, Jennifer J

    2017-01-01

    Background Clinicians are important stakeholders in the translation of well-designed research evidence into clinical practice for optimal patient care. However, the application of knowledge translation (KT) theories and processes may present conceptual and practical challenges for clinicians. Online learning platforms are an effective means of delivering KT education, providing an interactive, time-efficient, and affordable alternative to face-to-face education programs. Objective This study ...

  19. Fascia--Current knowledge and future directions in physiatry: narrative review.

    Science.gov (United States)

    Kwong, Evan H; Findley, Thomas W

    2014-01-01

    Fascia can be considered part of the connective tissues that permeates the human body. However, in medical training its definition is not clear, and even among specialists its role is not completely understood. Physiatrists have a unique opportunity to add to the growing scientific and clinical knowledge about fascia, particularly about how this connective tissue network may apply clinically to musculoskeletal disorders. In this narrative review, the structure and function of fascia is discussed from the perspective of physiatry.

  20. Current Challenges for the Knowledge Society. Toward Digital Inclusion in Latin America

    Directory of Open Access Journals (Sweden)

    Migdalia Pineda

    2009-08-01

    Full Text Available This work makes reference to the subject of the present challenges of the society of the knowledge as far as the profit of the digital inclusion, mainly in Latin America, for which one stops in analyzing the incidence of the technologies of the information and the communication in the construction of the knowledge in the contemporary societies. Also, one approaches the problem of the social innovation in the production of popular contents and knowledge, and of the social inclusion like condition indispensable for an inclusion sustained in the social appropriation of the TIC. Methodologically, the investigation when being cradle in an ampler theoretical study, at the moment in course, titleholder: “Society of the Information, post modernity and culture of masses”, is of documentary and bibliographical character, so that it makes a conceptual analysis of the subjects boarded. Finally some actions and recommendations for the digital inclusion set out, by means of the creation of social networks, the sectors and worked against communities more in the zone.

  1. [Prophylaxis of bacterial endocarditis in children with congenital heart disease: current status of parents' knowledge].

    Science.gov (United States)

    Pérez-Piaya Moreno, M R; de Diego Fernández, P; Chinchilla Molina, J M; de Haro López, M A; Sánchez Calderón, M; Rodríguez Vázquez del Rey, M M; Malagón Arquillo, C; Madrid Pinilla, A; Pérez de la Cruz, J M

    1997-10-01

    The purpose of this study was to assess the knowledge that parents of children with congenital cardiac disease have about bacterial endocarditis (EB) and its prophylaxis (PEB). To this end, an elusive questionnaire was prepared and offered to one hundred parents of children who needed PEB. The group was classified according to the age of the children, the cultural level of the parents an the event of a dental or if another septic focus was known in the past. Likewise, the parents' knowledge of their child's disease was analyzed. Of the results obtained, it stood-out that the parents appeared well informed about their child's illness, but their information was insufficient in relationship to EB and PEB. Of those tested, 85% defined the child's heart disease, while only 14% did so for EB. Likewise, only 67.7% of the children who underwent an intervention for a septic focus performed PEB correctly. The knowledge of this theme are in relationship to the family's cultural formation. We emphasize the need to reinforce the information about PEB that the cardiologists, pediatricians and general physicians give to the families in order to prevent the morbidity and mortality caused by EB.

  2. Active to sterile neutrino mixing limits from neutral-current interactions in MINOS

    Energy Technology Data Exchange (ETDEWEB)

    Adamson, P.; /Fermilab; Auty, D.J.; /Sussex U.; Ayres, D.S.; /Argonne; Backhouse, C.; /Oxford U.; Barr, G.; /Oxford U.; Bishai, M.; /Brookhaven; Blake, A.; /Cambridge U.; Bock, G.J.; /Fermilab; Boehnlein, D.J.; /Fermilab; Bogert, D.; /Fermilab; Cavanaugh, S.; /Harvard U., Phys. Dept. /Tufts U.

    2011-04-01

    Results are reported from a search for active to sterile neutrino oscillations in the MINOS long-baseline experiment, based on the observation of neutral-current neutrino interactions, from an exposure to the NuMI neutrino beam of 7.07 x 10{sup 20} protons on target. A total of 802 neutral-current event candidates is observed in the Far Detector, compared to an expected number of 754 {+-} 28(stat.) {+-} 37(syst.) for oscillations among three active flavors. The fraction f{sub s} of disappearing {nu}{sub {mu}} that may transition to {nu}{sub s} is found to be less than 22% at the 90% C.L.

  3. A Secondary-Control Based Fault Current Limiter for Four-Wire Three Phase Inverter-Interfaced DGs

    DEFF Research Database (Denmark)

    Beheshtaein, Siavash; Savaghebi, Mehdi; Guerrero, Josep M.

    2017-01-01

    Fault current limiters (FCLs) are one class of solutions to cope with the upcoming challenges in microgrid protection. Considering high penetration of distributed generations (DGs) in microgrids, the necessity of designing cheap and effective FCL is getting higher. This paper attempts to fill...

  4. Fault Ride Though Control of Photovoltaic Grid-connected Inverter with Current-limited Capability under Offshore Unbalanced Voltage Conditions

    DEFF Research Database (Denmark)

    Liu, Wenzhao; Guo, Xiaoqiang; Savaghebi, Mehdi

    2016-01-01

    The photovoltaic (PV) inverter installed on board experiences the excessive current stress in case of the offshore unbalanced voltage fault ride through (FRT), which significantly affects the operation reliability of the power supply system. In order to solve the problem, the inherent mechanism...... of the excessive current phenomenon with the conventional fault ride through control is discussed. The quantitative analysis of the current peak value is conducted and a new current-limiting control strategy is proposed to achieve the flexible power control and successful fault ride through in a safe current...... operation area, which is beneficial to the system reliability. Finally, the simulations of conventional and proposed control solutions are carried out. The results verify the effectiveness of the proposed method....

  5. Multiple Transportable Carbohydrates During Exercise: Current Limitations and Directions for Future Research.

    Science.gov (United States)

    Wilson, Patrick B

    2015-07-01

    The concept of multiple transportable carbohydrates (MTC) refers to a combination of saccharides that rely on distinct transporters for intestinal absorption. Ingestion of MTC during prolonged exercise has been purported to increase carbohydrate absorption efficiency, increase exogenous carbohydrate oxidation, reduce gastrointestinal (GI) distress, and improve athletic performance when carbohydrate intake is high (>50-60 g·h⁻¹). Although reviews of MTC research have been published previously, a comprehensive literature evaluation underscoring methodological limitations has not been conducted to guide future work. Accordingly, this review outlined the plausible mechanisms of MTC and subsequently evaluated MTC research based on several factors, including participant characteristics, exercise modality, exercise task, treatment formulation, treatment blinding, and pre-exercise nutrition status. A total of 27 articles examining MTC during exercise were identified and reviewed. Overall, ingestion of MTC led to increased exogenous carbohydrate oxidation, reduced GI distress, and improved performance during cycling lasting ≥2.5 hours, particularly when carbohydrate was ingested at ≥1.2 g·min⁻¹. Despite the apparent benefits, several limitations in the literature were apparent, including that only 3 studies used running, only 2 studies were conducted in the field, most participants were fasted, and women and adolescents were underrepresented. In addition, the majority of the studies fed carbohydrate at ≥1.2 g·min⁻¹, which may have inflated levels of GI distress and exaggerated performance decrements with single-saccharide feedings. Based on these limitations, future MTC investigations should consider focusing on running, examining team-based sports, including women and adolescents, conducting experiments under field conditions, examining the modifying effects of pre-exercise nutrition, and using modest feeding protocols (1.0-1.2 g·min⁻¹).

  6. How Do Clinicians Learn About Knowledge Translation? An Investigation of Current Web-Based Learning Opportunities.

    Science.gov (United States)

    Damarell, Raechel A; Tieman, Jennifer J

    2017-07-13

    Clinicians are important stakeholders in the translation of well-designed research evidence into clinical practice for optimal patient care. However, the application of knowledge translation (KT) theories and processes may present conceptual and practical challenges for clinicians. Online learning platforms are an effective means of delivering KT education, providing an interactive, time-efficient, and affordable alternative to face-to-face education programs. This study investigates the availability and accessibility of online KT learning opportunities for health professionals. It also provides an analysis of the types of resources and associated disciplines retrieved by a range of KT synonyms. We searched a range of bibliographic databases and the Internet (Google advanced option) using 9 KT terms to identify online KT learning resources. To be eligible, resources had to be free, aimed at clinicians, educational in intent, and interactive in design. Each term was searched using two different search engines. The details of the first 100 websites captured per browser (ie, n=200 results per term) were entered into EndNote. Each site was subsequently visited to determine its status as a learning resource. Eligible websites were appraised for quality using the AACODS (Authority, Accuracy, Coverage, Objectivity, Date, Significance) tool. We identified 971 unique websites via our multiple search strategies. Of these, 43 were health-related and educational in intent. Once these sites were evaluated for interactivity, a single website matched our inclusion criteria (Dementia Knowledge Translation Learning Centre). KT is an important but complex system of processes. These processes overlap with knowledge, practice, and improvement processes that go by a range of different names. For clinicians to be informed and competent in KT, they require better access to free learning opportunities. These resources should be designed from the viewpoint of the clinician, presenting KT

  7. HISTORICAL CRITICAL PEDAGOGY AND OBJECTIVE KNOWLEDGE VERSUS THE MULTICULTURALISM AND RELATIVISM CURRENT ACADEMIC DEBATE

    Directory of Open Access Journals (Sweden)

    Julia Malanchen

    2015-06-01

    Full Text Available The article discusses the existing antagonistic understanding among the authors who discuss curriculum from the multiculturalist perspective and the authors of the Historical-Critical Pedagogy. The aim is to explain the postmodern relativists bases and multiculturalism, which opposes the defense of objective knowledge as central to the organization of a curriculum. Finally we point out what content should integrate an academic, with the objective, human development, human emancipation and social transformation, which allow the human being aim to provide social and consciously so increasingly free and universal.

  8. Systematic review of the current status of programs and general knowledge of diagnosis and management of retinoblastoma

    Directory of Open Access Journals (Sweden)

    Marco A. Ramírez-Ortiz

    2017-01-01

    Conclusions: There is an immediate need in Mexico to expand primary care providers’ knowledge of Rb and to expand and upgrade current Rb programs to meet the needs of the population adequately. Diagnosis and care of Rb patients in Mexico can also be improved by the establishment of a national Rb registry and a national early detection program, and by increased use of the national treatment protocol.

  9. A Review on Current Status of Stability and Knowledge on Liquid Electrolyte-Based Dye-Sensitized Solar Cells

    Directory of Open Access Journals (Sweden)

    Frédéric Sauvage

    2014-01-01

    Full Text Available The purpose of this review is to gather the current background in materials development and provide the reader with an accurate image of today’s knowledge regarding the stability of dye-sensitized solar cells. This contribution highlights the literature from the 1970s to the present day on nanostructured TiO2, dye, Pt counter electrode, and liquid electrolyte for which this review is focused on.

  10. Dietary fibre in Europe: current state of knowledge on definitions, sources, recommendations, intakes and relationships to health

    DEFF Research Database (Denmark)

    Stephen, Alison M; Champ, Martine M-J; Cloran, Susan J

    2017-01-01

    , particularly from national surveys across Europe and around the world. It also assessed current knowledge on health effects of dietary fibre and related the impact of different fibre types on health. The overall intent was to be able to provide more detailed guidance on the types of fibre which should...... be consumed for good health, rather than simply a total intake figure, the current situation. Analysis of data indicated a fair degree of uniformity in the definition of dietary fibre, the method used for analysis, the recommended amount to be consumed and a growing literature on effects on digestive health...

  11. Modelling marine sediment biogeochemistry: Current knowledge gaps, challenges, and some methodological advice for advancement

    DEFF Research Database (Denmark)

    Lessin, Gennadi; Artioli, Yuri; Almroth-Rosell, Elin

    2018-01-01

    models, reduce risk of bias, and clarify model limitations; (B) extended cross-disciplinary approach to promote effective collaboration between modelling and empirical scientists of various backgrounds and better involvement of stakeholders and end-users; (C) a common vocabulary for terminology used...

  12. The ecotoxicity of graphene family materials: current status, knowledge gaps and future needs

    Energy Technology Data Exchange (ETDEWEB)

    Jastrzębska, Agnieszka Maria, E-mail: agsolgala@gmail.com; Olszyna, Andrzej Roman, E-mail: aolszyna@meil.pw.edu.pl [Warsaw University of Technology, Faculty of Materials Science and Engineering (Poland)

    2015-01-15

    Recently, graphene family materials (GFMs) have been introduced among all fields of science and still get numerous attention. Also, the applicability of these materials in many areas makes them very attractive. GFMs have attracted both academic and industrial interest as they can produce a dramatic improvement in materials properties at very low filler content. The aim of this review is to identify, summarize, and present the first available information on the influence of GFMs on soil and water environment as well as identify the knowledge gaps and indicate the directions for the next generation of the original scientific investigations. The paper also presents our first preliminary impact assessment and potential pathways of GFMs distribution in the environment. We used as an example the reduced graphene oxide/Al{sub 2}O{sub 3} nanocomposite (RGO/Al{sub 2}O{sub 3}) that has been previously designed and synthesized by us. Authors believe that further work should focus on improvement of characterization methodology applicable for ecotoxicity analyses and possible interactions between GFMs and different living ecosystems. Consequently, the potential impact of graphene and its derivatives on environmental health is a matter of academic interest. However, potential hazards sufficient for risk assessment and concerned with GFMs usage in consumer products first need to be investigated and identified. Further research should focus on gathering knowledge on GFMs properties for life cycle analyses, which still poses a great challenge for scientists.

  13. [Translational research in gestational diabetes mellitus and mild gestational hyperglycemia: current knowledge and our experience].

    Science.gov (United States)

    Rudge, Marilza Vieira Cunha; Piculo, Fernanda; Marini, Gabriela; Damasceno, Débora Cristina; Calderon, Iracema Mattos Paranhos; Barbosa, Angélica Pascon

    2013-10-01

    Maternal diabetes constitutes an unfavorable environment for fetal-placental and embryonic development. It is has important repercussion in modern obstetrics, since it is associated to an increased risk of neonatal and maternal morbidity, and it still is a significant medical challenge. The increased occurrence of diabetes worldwide, the increase in diabetes type 2 in women at reproductive age and the crossed generation of intrauterine programming for diabetes type 2 are the bases for the growing interest in utilization of diabetic experimental samples, with the aim to acquire knowledge about the mechanisms that induce development alterations in gestational diabetes. Several studies have shown the benefits of diabetes prevention, with interventions in lifestyle, metabolic improvement and control of cardiovascular risk factors to substantially prevent the complications of this devastating disease. Despite these findings, the recent revolution in the scientific knowledge, and the infinite number of new therapies for diabetes, there is still a large gap between what was learned through research and what is really done in public, clinical and community health. The negative economic impact of this complacency in people, families, and national economies is alarming. It is expected that translational research in the binomial diabetes and pregnancy are implemented in centers of excellence, in both basic and applied research, and complemented by multicenter clinical studies, conducted in a pragmatic way to increase the level of scientific evidence with more reliable diagnostic and propaedeutic resources.

  14. Intestinal fibrosis in inflammatory bowel disease - Current knowledge and future perspectives.

    Science.gov (United States)

    Rieder, Florian; Fiocchi, Claudio

    2008-12-01

    Intestinal fibrosis is a common complication of IBD that can become seriously symptomatic and may require surgical intervention if stricture formation ensues. This review discusses existing and developing knowledge of intestinal fibrosis and its implications for therapy. Review of the literature, personal communications, unpublished observations. Known mechanisms of intestinal fibrosis include fibroblast proliferation and migration, activation of stellate cells, and extraintestinal fibroblast recruitment. However, novel mechanisms are being uncovered, including epithelial-to-mesenchymal transition, endothelial-to-mesenchymal transition, pericyte differentiation, and fibrocyte recruitment. Most of the traditional and novel mechanisms underlying intestinal fibrosis are associated to the presence of chronic inflammation, but is also possible that fibrosis develops independently of persistent immune activation in the gut. At the moment, the development of preventive, non-interventional, and more effective management of intestinal fibrosis is hampered by the lack of a greater knowledge of its basic pathophysiology and predisposing factors. It is reasonable to expect that therapy of IBD-associated fibrosis will radically improve once the underlying mechanisms are better understood, and therapeutic modalities will emerge that prevent or reverse this complication of IBD.

  15. Parasites of importance for human health in Nigerian dogs: high prevalence and limited knowledge of pet owners

    Directory of Open Access Journals (Sweden)

    Heukelbach Jorg

    2008-12-01

    Full Text Available Abstract Background Dogs are the most common pet animals worldwide. They may harbour a wide range of parasites with zoonotic potential, thus causing a health risk to humans. In Nigeria, epidemiological knowledge on these parasites is limited. Methods In a community-based study, we examined 396 dogs in urban and rural areas of Ilorin (Kwara State, Central Nigeria for ectoparasites and intestinal helminths. In addition, a questionnaire regarding knowledge and practices was applied to pet owners. Results Nine ectoparasite species belonging to four taxa and six intestinal helminth species were identified: fleas (Ctenocephalides canis, Pulex irritans, Tunga penetrans, mites (Demodex canis, Otodectes sp., Sarcoptes scabiei var. canis, ticks (Rhipicephalus sanguineus, Ixodes sp., and lice (Trichodectes canis; and Toxocara canis, Ancylostoma sp., Trichuris vulpis, Dipylidium caninum, Taenidae and Strongyloides sp. Overall prevalence of ectoparasites was 60.4% and of intestinal helminths 68.4%. The occurrence of C. canis, R. sanguineus, T. canis, Ancylostoma sp. and T. vulpis was most common (prevalence 14.4% to 41.7%. Prevalence patterns in helminths were age-dependent, with T. canis showing a decreasing prevalence with age of host, and a reverse trend in other parasite species. Knowledge regarding zoonoses was very limited and the diseases not considered a major health problem. Treatment with antiparasitic drugs was more frequent in urban areas. Conclusion Parasites of importance for human health were highly prevalent in Nigerian dogs. Interventions should include health education provided to dog owners and the establishment of a program focusing on zoonotic diseases.

  16. Deliberate Microbial Infection Research Reveals Limitations to Current Safety Protections of Healthy Human Subjects.

    Science.gov (United States)

    Evers, David L; Fowler, Carol B; Mason, Jeffrey T; Mimnall, Rebecca K

    2015-08-01

    Here we identify approximately 40,000 healthy human volunteers who were intentionally exposed to infectious pathogens in clinical research studies dating from late World War II to the early 2000s. Microbial challenge experiments continue today under contemporary human subject research requirements. In fact, we estimated 4,000 additional volunteers who were experimentally infected between 2010 and the present day. We examine the risks and benefits of these experiments and present areas for improvement in protections of participants with respect to safety. These are the absence of maximum limits to risk and the potential for institutional review boards to include questionable benefits to subjects and society when weighing the risks and benefits of research protocols. The lack of a duty of medical care by physician-investigators to research subjects is likewise of concern. The transparency of microbial challenge experiments and the safety concerns raised in this work may stimulate further dialogue on the risks to participants of human experimentation.

  17. A "pancreatic tooth" design best accommodates the limitations of current artificial pancreas technology.

    Science.gov (United States)

    Lim, Michael Wee-Kong; Fan, Tai-Ping

    2007-01-01

    Inadequately responsive glycaemic control is an important factor in the causation of diabetic end-organ damage. Artificial or hybrid bioartificial pancreases can provide responsive glycaemic control that can reduce the enormous personal suffering and socio-economic costs of diabetes. However, they share the shortcomings of limited operational life, due to depletion of stores or failure of component parts. A pancreatic tooth design provides accessibility for the purposes of replenishment or replacement. In addition, the mouth also provides a sheltered location, is more resistant to diabetic changes and less prone to thermoregulatory changes than subcutaneous tissues, and is adapted to cope with the occasional pathogen load. The device would consist of two parts: a permanent implant with an angiogenic capillary plexus that is the blood contacting interface and a crown containing the artificial or bio-artificial pancreatic systems: the accessibility of which confers ease of replenishment and replacement, among other advantages.

  18. Comparative study of superconducting fault current limiter both for LCC-HVDC and VSC-HVDC systems

    Science.gov (United States)

    Lee, Jong-Geon; Khan, Umer Amir; Lim, Sung-Woo; Shin, Woo-ju; Seo, In-Jin; Lee, Bang-Wook

    2015-11-01

    High Voltage Direct Current (HVDC) system has been evaluated as the optimum solution for the renewable energy transmission and long-distance power grid connections. In spite of the various advantages of HVDC system, it still has been regarded as an unreliable system compared to AC system due to its vulnerable characteristics on the power system fault. Furthermore, unlike AC system, optimum protection and switching device has not been fully developed yet. Therefore, in order to enhance the reliability of the HVDC systems mitigation of power system fault and reliable fault current limiting and switching devices should be developed. In this paper, in order to mitigate HVDC fault, both for Line Commutated Converter HVDC (LCC-HVDC) and Voltage Source Converter HVDC (VSC-HVDC) system, an application of resistive superconducting fault current limiter which has been known as optimum solution to cope with the power system fault was considered. Firstly, simulation models for two types of LCC-HVDC and VSC-HVDC system which has point to point connection model were developed. From the designed model, fault current characteristics of faulty condition were analyzed. Second, application of SFCL on each types of HVDC system and comparative study of modified fault current characteristics were analyzed. Consequently, it was deduced that an application of AC-SFCL on LCC-HVDC system with point to point connection was desirable solution to mitigate the fault current stresses and to prevent commutation failure in HVDC electric power system interconnected with AC grid.

  19. Microbiology of Wind-eroded Sediments: Current Knowledge and Future Research Directions

    Science.gov (United States)

    Wind erosion is a threat to the sustainability and productivity of soils that takes place at local, regional, and global scales. Current estimates of cost of wind erosion have not included the costs associated with the loss of soil biodiversity and reduced ecosystem functions. Microorganisms carrie...

  20. Sensor technologies aiming at fall prevention in institutionalized old adults : A. synthesis of current knowledge

    NARCIS (Netherlands)

    Kosse, N. M.; Brands, K.; Bauer, J. M.; Hortobagyi, T.; Lamoth, C. J. C.

    Background: Falls are a serious health problem in old adults especially in nursing home residents and hospitalized patients. To prevent elderly from falling, sensors have been increasingly used in intramural care settings. However, there is no clear overview of the current used technologies and

  1. Current Limitations and Recommendations to Improve Testing for the Environmental Assessment of Endocrine Active Substances

    DEFF Research Database (Denmark)

    Coady, Katherine K; Biever, Ronald C; Denslow, Nancy D

    2017-01-01

    existing test methods are resource intensive in regard to time, cost, and use of animals. However, based on recent experiences, there are opportunities to improve approaches to, and guidance for existing test methods, and reduce uncertainty. For example, in vitro high throughput screening could be used......In this paper existing regulatory frameworks and test systems for assessing potential endocrine-active chemicals are described, and associated challenges discussed, along with proposed approaches to address these challenges. Regulatory frameworks vary somewhat across geographies, but all basically...... evaluate whether a chemical possesses endocrine activity and whether this activity can result in adverse outcomes either to humans or the environment. Current test systems include in silico, in vitro and in vivo techniques focused on detecting potential endocrine activity, and in vivo tests that collect...

  2. Regadenoson use in patients with chronic obstructive pulmonary disease: the state of current knowledge.

    Science.gov (United States)

    Golzar, Yasmeen; Doukky, Rami

    2014-01-01

    Stress testing is challenging in patients with chronic obstructive pulmonary disease (COPD). Functional capacity is generally decreased in this patient population, limiting patients' ability to achieve physiologic stress through exercise. Additionally, due to emphysematous changes, COPD patients tend to have poor acoustic windows that impair the quality and therefore diagnostic accuracy of stress echocardiography techniques. Pharmacologic stress myocardial perfusion imaging (MPI) testing is also problematic, particularly due to the concern for adenosine-induced bronchoconstriction with conventional vasodilator stress agents. Regadenoson, a selective A2A adenosine receptor agonist, has gained popularity due to its ease of administration and improved patient experience in the general population. The literature describing the experience with regadenoson in COPD patients, though limited, is rapidly growing and reassuring. This review summarizes the pharmacology and clinical application of this novel stress agent and presents the available data on the safety and tolerability of its use in COPD patients.

  3. Mapping fire effects on ash and soil properties. Current knowledge and future perspectives.

    Science.gov (United States)

    Pereira, Paulo; Cerda, Artemi; Strielko, Irina

    2014-05-01

    floor consumption (Lewis et al., 2011), ash cover (Robichaud et al., 2007) and other aspects related with soil as the vegetation factors that affect post-fire erosion risk (Fox et al., 2008). Field studies had also indented to estimate and map the impacts of fire in soil properties. Contrary to remote sensing studies, the mapping of fire effects on ash and soil properties in the field is specially carried out at small scale (e.g. slope or plot). The small scale resolution studies are important because identify small patterns that are normally ignored by remote sensing studies, but fundamental to understand the post-fire evolution of the burned areas. One of the important aspects of the small scale studies of fire effect on ash and soil properties is the great spatial variability, showing that the impact of fire is extremely heterogeneous in space and time (Outeiro et al., 2008; Pereira et al. in press). The small scale mapping of fire effects on soil properties normally is carried out using Geostatistical methods or using deterministic interpolation methods (Robichaud and Miller, 1999; Pereira et al., 2013). Several reports were published on the spatial distribution and mapping of ash and duff thickness (Robichaud and Miller, 1999; Pereira et al., 2013; Pereira et al. in press), fire severity (Pereira et al., 2014), ash chemical characteristics as total nitrogen (Pereira et al., 2010a), and ash extractable elements (Pereira et al., 2010b). Also, previous works mapped fire effects on soil temperature (Gimeno-Garcia et al., 2004), soil hydrophobicity (Woods et al., 2007), total nitrogen (Hirobe et al., 2003), phosphorous (Rodriguez et al., 2009) and major cations (Outeiro et al., 2008). It is important to integrate remote sensing and field based works of fire effects on ash and soil properties in order to have a better validation of the models predicted. The aim of this work is present the current knowledge about mapping fire effects in ash and soil properties at diverse

  4. Thomson Scientific's expanding Web of Knowledge: beyond citation databases and current awareness services.

    Science.gov (United States)

    London, Sue; Brahmi, Frances A

    2005-01-01

    As end-user demand for easy access to electronic full text continues to climb, an increasing number of information providers are combining that access with their other products and services, making navigating their Web sites by librarians seeking information on a given product or service more daunting than ever. One such provider of a complex array of products and services is Thomson Scientific. This paper looks at some of the many products and tools available from two of Thomson Scientific's businesses, Thomson ISI and Thomson ResearchSoft. Among the items of most interest to health sciences and veterinary librarians and their users are the variety of databases available via the ISI Web of Knowledge platform and the information management products available from ResearchSoft.

  5. Chilean jagged lobster, Projasus bahamondei, in the southeastern Pacific Ocean: current state of knowledge

    Directory of Open Access Journals (Sweden)

    Patricio M Arana

    2014-03-01

    Full Text Available The Chilean jagged lobster (Projasus bahamondei is a deep-water crustacean (175-550 m occurring in certain areas of the southeastern Pacific Ocean, including the Nazca Ridge, Desventuradas Islands, the Juan Fernandez archipelago and ridge, and the continental slope off the central coast of Chile. This review describes the taxonomic status, geographical and bathymetric distribution, some biological aspects and habitat characteristics of this species. Additionally, both artisanal and industrial exploitation attempts made within the region are detailed, as well as fishing operation results, chemical composition, different elaboration procedures and the destination of the catch. The main objectives of this review are to contribute to the knowledge of P. bahamondei as a component of the deep-sea ecosystem and to highlight its importance as a potential fishery resource.

  6. The invasive mosquito species Aedes albopictus: current knowledge and future perspectives

    Science.gov (United States)

    Bonizzoni, Mariangela; Gasperi, Giuliano; Chen, Xioaguang; James, Anthony A.

    2013-01-01

    One of the most dynamic events in public health is being mediated by the global spread of the invasive mosquito Aedes albopictus. Its rapid expansion and vectorial capacity for various arboviruses affect an increasingly larger proportion of the world population. Responses to the challenges of controlling this vector are expected to be enhanced by an increased knowledge of its biology, ecology, and vector competence. Details of population genetics and structure will allow following, and possibly predicting, the geographical and temporal dynamics of its expansion, and will inform the practical operations of control programs. Experts are coming together now to describe the history, characterize the present circumstances, and collaborate on future efforts to understand and mitigate this emerging public health threat. PMID:23916878

  7. Epigenetic mechanisms of breast cancer: an update of the current knowledge.

    Science.gov (United States)

    Karsli-Ceppioglu, Seher; Dagdemir, Aslihan; Judes, Gaëlle; Ngollo, Marjolaine; Penault-Llorca, Frédérique; Pajon, Amaury; Bignon, Yves-Jean; Bernard-Gallon, Dominique

    2014-01-01

    Epigenetic alterations are heritable changes in gene expression that occur without causing any change in DNA sequence. They are important key factors for cancer development and prognosis. Breast cancer is induced by the accumulation of altered gene regulation. Besides genetic mutations, epigenetics mechanisms have an important role in breast cancer tumorigenesis. Investigations related with aberrant epigenetic regulations in breast cancer focus on initiating molecular mechanisms in cancer development, identification of new biomarkers to predict breast cancer aggressiveness and the potential of epigenetic therapy. In this review, we will summarize the recent knowledge about the role of epigenetic alterations related with DNA methylation and histone modification in breast cancer. In addition, altered regulation of breast cancer specific genes and the potential of epigenetic therapy will be discussed according to epigenetic mechanisms.

  8. Current gaps in basic science knowledge of botulinum neurotoxin biological actions.

    Science.gov (United States)

    Rossetto, Ornella; Pirazzini, Marco; Montecucco, Cesare

    2015-12-01

    Botulinum neurotoxins are produced by anaerobic spore-forming bacteria of the genus Clostridium in several dozens of variants that inactivate neurotransmitter release owing to their metalloprotease activity. This results in a persistent paralysis of peripheral nerve terminals known as botulism. They are the most potent toxins known and are classified as one of the six highest-risk threat agents of bioterrorism. Despite their high toxicity, two of them are used as valuable pharmaceutical for the therapy of many neurological and non-neurological disorders. Notwithstanding the many advances in our understanding of the genetics and structure of botulinum neurotoxins, there are still many gaps in knowledge of toxin mechanism of action that will be discussed here. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Melatonin and cancer: current knowledge and its application to oral cavity tumours.

    Science.gov (United States)

    Cutando, Antonio; Aneiros-Fernández, José; Aneiros-Cachaza, José; Arias-Santiago, Salvador

    2011-09-01

    Melatonin (MLT) is a molecule secreted by the pineal gland in cyclical periods. In mammals, MLT is involved in physiological processes, such as sleep/wake regulation in the circadian cycle. It has antioxidant and anti-inflammatory properties, functions as an immunomodulator, and stimulates bone metabolism. MLT is also involved in tumour processes in breast, prostate, liver, and bone cancers, among others, and in oral cavity tumours like epidermoid carcinoma. We are gradually increasing our knowledge of the underlying mechanism of MLT action in the aforementioned tumour processes, in which MT1, MT2, MT3, and RZR receptors appear to play a highly important role. These receptors belong to a large family of G-protein-coupled transmembrane receptors, some of which have been linked to melatonin's anticancer action, to tumour growth, and to prognosis. The objective of this article is to provide a clear review of research into the range of MLT functions, focusing specifically on MT receptors. We aim to contribute interesting, new approaches to research into oral cavity tumours. An extensive review of the research literature was conducted using PubMed, Science Direct, ISI Web of Knowledge, and the Cochrane base. This study highlights the growing importance of MLT in the prognosis and treatment of certain tumours, including epidermoid carcinoma in the oral cavity. Moreover, it opens up a highly original, encouraging line of research in the field of tumours. MLT contributes to protecting the oral cavity from tissue damage caused by receptor action. Experimental evidence suggests that it may be useful in the treatment and prognosis of tumour processes in the oral cavity. © 2011 John Wiley & Sons A/S.

  10. Biogenic volatile organic compound emissions from the Eurasian taiga: current knowledge and future directions

    Energy Technology Data Exchange (ETDEWEB)

    Rinne, J. (Dept. of Physics, Univ. of Helsinki (Finland)); Baeck, J. (Dept. of Forest Ecology, Univ. of Helsinki (Finland)); Hakola, H. (Finnish Meteorological Institute, Air Quality Research, Helsinki (Finland))

    2009-07-01

    n this paper, the research conducted on the emissions of the biogenic volatile organic compounds (BVOCs) from the European boreal zone, or taiga, is reviewed. We highlight the main findings and the key gaps in our knowledge. Ecosystem scale BVOC emissions from the Eurasian taiga are observed to be relatively low as compared with those from some forest ecosystems in warmer climates. One of the distinctive features of the Eurasian taiga is the predominance of monoterpene emitting coniferous trees. Recent research indicates that in addition to evaporation from storage structures, part of the monoterpene emission of conifers originates directly from synthesis. Monoterpene emission from boreal deciduous trees originates mainly directly from synthesis. The boreal trees exhibit distinct intra-species variation in the monoterpene mixtures they emit. Important sources of isoprene in the Eurasian taiga include Norway spruce, open wetland ecosystems and some non-dominant woody species, such as European aspen and willows. Many boreal tree species also emit non-terpenoid compounds and highly reactive sesquiterpenes. The future challenges in the research on BVOC emissions from the Eurasian taiga include (i) quantification and understanding the non-terpenoid VOC emissions from the taiga ecosystems, (ii) bringing ecosystems in the eastern Eurasian taiga into the sphere of BVOC emission studies, (iii) establishing long-term ecosystem flux studies combined with plant physiological measurements, and (iv) integrating knowledge and research skills on BVOC synthesis, storages and emissions, land cover changes and atmospheric processes in different spatial and temporal scales in order to better understand the impact of biosphere on atmospheric chemistry and composition in changing climate. (orig.)

  11. [Leptospirosis in French Guiana and the Guiana shield: Current knowledge in 2016].

    Science.gov (United States)

    Epelboin, L; Bourhy, P; Le Turnier, P; Schaub, R; Mosnier, E; Berlioz-Arthaud, A; Reynaud, Y; Nacher, M; De Thoisy, B; Carles, G; Richard-Hansen, C; Demar, M; Picardeau, M; Djossou, F

    2017-08-01

    Leptospirosis is a cosmopolitan zoonosis caused by bacteria of the genus Leptospira. Whether the distribution is worldwide, the hot and humid climate of the tropics is particularly conducive to its expansion. In most French overseas departments and territories, leptospirosis is considered as a public health problem. In French Guiana, a French department located in the northeastern part of the Amazon rainforest, it is supposed to be rare. The objective of this review was to make an inventory of the knowledge on human and animal leptospirosis in French Guiana and neighboring countries. A comprehensive search was conducted through the indexed and informal medical literature in English, French, Spanish and Portuguese. Thus, respectively ten and four publications were identified on human and animal leptospirosis in French Guiana, published between 1940 and 1995 in the form of case reports or case series. The publications concerning this disease in the other countries of the Guiana Shield, eastern Venezuela, Guyana, Suriname, and Brazilian state of Amapá, also scarce or nonexistent. However recent data from the French National Centre of leptospirosis showed a recent and sudden increase in the number of cases in the department, probably partly due to the development of diagnostic tools such as Elisa IgM serology. It is likely that leptospirosis is a neglected disease in the region, due to the lack of diagnostic tools readily available, the lack of knowledge of the local clinicians on this disease and the existence of many other pathogens with similar clinical presentation such as malaria, arboviruses and Q fever and Amazonian toxoplasmosis. The establishment of more large-scale studies on animal and human leptospirosis is necessary and urgent to know the true burden of this disease in our region.

  12. Current knowledge and perspectives on biofilm formation: the case of Listeria monocytogenes.

    Science.gov (United States)

    da Silva, Eliane Pereira; De Martinis, Elaine Cristina Pereira

    2013-02-01

    Listeriosis is a rare, serious, and mainly food-borne infection caused by the bacterium Listeria monocytogenes. This food-borne infection primarily affects pregnant women and immunologically compromised individuals. L. monocytogenes is recognized as a problem for the food industry, mainly due to its environmental persistence, attributed in part to its ability to form biofilms. Biofilms are microbial communities adhered to biotic or abiotic surfaces coated by self-produced extracellular polymers. These structures confer protection to bacterial cells and decrease the efficiency of cleaning and disinfection procedures. This article presents a brief review of current perspectives on the formation of biofilms, with emphasis on L. monocytogenes, highlighting the importance of cell-to-cell communication and structural composition of the microbial communities. The techniques currently used to study biofilms and the need to develop new strategies for the prevention and control of biofilm-forming pathogens are also discussed.

  13. Pancreatic cystic neoplasms: Review of current knowledge, diagnostic challenges, and management options

    Science.gov (United States)

    Jana, Tanima; Shroff, Jennifer; Bhutani, Manoop S.

    2015-01-01

    Pancreatic cystic lesions are being detected with increasing frequency, largely due to advances in cross-sectional imaging. The most common neoplasms include serous cystadenomas, mucinous cystic neoplasms, intraductal papillary mucinous neoplasms, solid pseudopapillary neoplasms, and cystic pancreatic endocrine neoplasms. Computed tomography (CT), magnetic resonance imaging (MRI), and endoscopic ultrasound (EUS) are currently used as imaging modalities. EUS-guided fine needle aspiration has proved to be a useful diagnostic tool, and enables an assessment of tumor markers, cytology, chemistries, and DNA analysis. Here, we review the current literature on pancreatic cystic neoplasms, including classification, diagnosis, treatment, and recommendations for surveillance. Data for this manuscript was acquired via searching the literature from inception to December 2014 on PubMed and Ovid MEDLINE. PMID:25821410

  14. Some current applications, limitations and future perspectives of lactic acid bacteria as probiotics.

    Science.gov (United States)

    Evivie, Smith Etareri; Huo, Gui-Cheng; Igene, John Oamen; Bian, Xin

    2017-01-01

    Several mechanism and non-mechanism-based studies supporting the claim that lactic acid bacteria (LAB) strains confer health benefits and play immune-modulatory roles were examined in this review. Probiotic applications of LAB on global burdens such as obesity and type-2 diabetes were discussed as well as the use of yoghurt and ice cream as important vehicles to convey several beneficial LAB strains. Probiotic and symbiotic dairy products may be used in the nearest future to treat a variety of health disorders. Current studies suggest that lactic acid bacteria possess anti-obesity and anti-diabetic propensities on their hosts and thus can play a crucial role in human health care. Research in the rheological and physicochemical properties of ice cream as well as its applications are also on the increase. These applications face certain hurdles including technological (for less developed countries), consumer acceptability of new functional foods may be influenced by culture, ethics or religion. There is need for more studies on the genetic basis for probiotic properties which will give further understanding regarding novel manipulation skills and applicability in nutrition and health sectors. More studies confirming the direct effects of probiotic LABs in lowering the spread of food-borne and other pathogens are also anticipated.

  15. Comparisons and Limitations of Current Definitions of Bronchopulmonary Dysplasia for the Prematurity and Respiratory Outcomes Program.

    Science.gov (United States)

    Poindexter, Brenda B; Feng, Rui; Schmidt, Barbara; Aschner, Judy L; Ballard, Roberta A; Hamvas, Aaron; Reynolds, Anne Marie; Shaw, Pamela A; Jobe, Alan H

    2015-12-01

    Bronchopulmonary dysplasia is the most common morbidity of prematurity, but the validity and utility of commonly used definitions have been questioned. To compare three commonly used definitions of bronchopulmonary dysplasia in a contemporary prospective, multicenter observational cohort of extremely preterm infants. At 36 weeks postmenstrual age, the following definitions of bronchopulmonary dysplasia were applied to surviving infants with and without imputation: need for supplemental oxygen (Shennan definition), National Institutes of Health Workshop definition, and "physiologic" definition after a room-air challenge. Of 765 survivors assessed at 36 weeks, bronchopulmonary dysplasia was diagnosed in 40.8, 58.6, and 32.0% of infants, respectively, with the Shennan, workshop and physiologic definitions. The number of unclassified infants was lowest with the workshop definition (2.1%) and highest with the physiologic definition (16.1%). After assigning infants discharged home in room air before 36 weeks as no bronchopulmonary dysplasia, the modified Shennan definition compared favorably to the workshop definition, with 2.9% unclassified infants. Newer management strategies with nasal cannula flows up to 4 L/min or more and 0.21 FiO2 at 36 weeks obscured classification of bronchopulmonary dysplasia status in 12.4% of infants. Existing definitions of bronchopulmonary dysplasia differ with respect to ease of data collection and number of unclassifiable cases. Contemporary changes in management of infants, such as use of high-flow nasal cannula, limit application of existing definitions and may result in misclassification. A contemporary definition of bronchopulmonary dysplasia that correlates with respiratory morbidity in childhood is needed. Clinical trial registered with www.clinicaltrials.gov (NCT01435187).

  16. Development of 6.6 kV/600 A superconducting fault current limiter using coated conductors

    Science.gov (United States)

    Yazawa, T.; Koyanagi, K.; Takahashi, M.; Toba, K.; Takigami, H.; Urata, M.; Iijima, Y.; Saitoh, T.; Amemiya, N.; Shiohara, Y.; Ito, T.

    2009-10-01

    As one of the programs in the Ministry of Economy, Trade and Industry (METI) project regarding R&D on superconducting coated conductor, three-phase superconducting fault current limiter (SFCL) for 6.6 kV application was developed and successfully tested. The developed SFCL was mainly comprised three-phase set of current limiting coils installed in a sub-cooled nitrogen cryostat with a GM cryocooler, circuit breakers and a sequence circuit. The whole system was installed in a cubicle. Two tapes of coated conductor were wound in parallel in each coil to obtain the rated current of 72 A rms. After developing the whole SFCL system, short circuit experiments were implemented with a short circuit generator. In a three-line ground fault test, the SFCL successfully restricted the prospected short circuit current over 1.6 kA to about 800 A by the applied voltage of 6.6 kV. The SFCL was installed in a user field and connected with a gas engine generator, followed by a consecutive operation. In this program, 600 A class FCL coil, with which four coated conductor tapes were wound, was also developed. The coil showed sufficiently low AC loss at the rated current. With these results, the program attained the planned target of the fundamentals for the 6.6 kV/600 A SFCL.

  17. Current limitations in the management of cardiovascular risk in rheumatoid arthritis.

    Science.gov (United States)

    Scott, Ian C; Ibrahim, Fowzia; Johnson, Deborah; Scott, David L; Kingsley, Gabrielle H

    2012-01-01

    Rheumatoid arthritis (RA) is associated with excess cardiovascular (CV) disease. Many studies have shown subclinical atherosclerosis in RA is associated with CV risk factors and inflammation. Their relationship with CV events has however received less attention. Furthermore, except for hypertension CV risk factor management has not been examined in a UK RA population. We therefore evaluated the contribution of RA specific and CV risk factors to CV events alongside the management of CV risk factors in RA patients. We assessed the prevalence, screening and treatment of CV risk factors in a cross-sectional survey of RA patients consecutively attending specialist clinics. We used binary logistic regression to examine relationships between CV events and RA and CV risk factors. We enrolled 309 patients (81% female; median age 60 years; median disease duration 8 years). 27 (9%) had previous CV events. 56% had hypertension, 42% hyperlipidaemia, 11% diabetes, 52% were ex/current smokers and 26% obese. Lipid status was unknown in one third. 47% of patients on anti-hypertensive agents were undertreated. CV events were associated with hyperlipidaemia (OR 13.5; 95% CI 3.9, 45.9), hypertension (OR 6.4; 95% CI 1.9, 21.9), having ever smoked (OR 2.7; 95% CI 1.1, 6.5), RA duration (OR 1.09; 95% CI 1.06, 1.13) and erosions (OR 2.9; 95% CI 1.1, 8.2). CV events are prevalent in RA. They are associated with CV risks and RA factors. Despite this burden we found CV risk factors were inadequately managed. A robust system to identify and treat CV risks in RA is required.

  18. Rationale for designing cavity preparations in light of current knowledge and technology.

    Science.gov (United States)

    Welk, D A; Laswell, H R

    1976-04-01

    No restorative material presently available is as good as supported tooth structure and it is unlikely that a usable dental restorative material with the physical properties of enamel will ever be developed. The purpose of cavity preparation is to remove carious material and preserve sound tooth structure. Any additional removal of tooth structure is necessary for the convenience of the operator or because of limitations of the restorative materials. Presently available esthetic restorative systems for nonfunctional areas and selected anterior functional areas allow for designing cavity preparations where the only two considerations are removal of caries (and unsupported enamel) and placement of retentive features. The problem of cavity design for restoration of functional surfaces is not answered easily, but there is reasonable hope that in the near future an esthetic restorative material will be available that has the strength and other necessary properties to serve in functional areas. There should be no specific "ideal" design for cavity preparation. Each defect should be custom designed to remove the caries or defect and perform the additional steps necessitated by the limitations of the operator or restorative material. As advocated by Black in one of his later publications, it is necessary to make mouth-by-mouth and tooth-by-tooth judgements concerning the most desirable outline form to be obtained.

  19. Lean philosophy and its applications in the service industry: a review of the current knowledge

    Directory of Open Access Journals (Sweden)

    Higor dos Reis Leite

    2015-09-01

    Full Text Available This article presents an in-depth bibliographic study about the creation, principles, evolution, and practices of the lean philosophy oriented to the services sector. More than 70 papers about “lean thinking” – specially with focus on services – have been carefully reviewed. It presents the principles of lean service in an organized way, companies applying lean service, and best practices and tools in the implementation of lean service. It shows that lean service does not have a single or specific model of tools, practices or standards. In fact, it is a mix of tools and practices that must be applied according the situation found to be improved. Despite the lack of a standards and methodology for use in services, its best practices, inherited from manufacturing, when applied to services can generate large economic and financial results, as well as improvement of workers’ behavior. But, like any change process, this study shows that the application of lean in services also suffers resistance. There might be limitations when evaluating lean practices and principles to services, specially those that have not yet been well defined and reported. Other limitations are due to the scarce articles in the literature. However, this research showed that the use of the lean philosophy in services proved to be effective and quite worthwhile. Several cases analyzed presented significant gains and confirmed an increasing and promising future for service companies “thinking lean”.

  20. Regadenoson use in patients with chronic obstructive pulmonary disease: the state of current knowledge

    Directory of Open Access Journals (Sweden)

    Golzar Y

    2014-01-01

    Full Text Available Yasmeen Golzar,1,2 Rami Doukky1,21Division of Adult Cardiology, John H Stroger Jr, Hospital of Cook County, 2Division of Cardiology, Rush University Medical Center, Chicago, IL, USAAbstract: Stress testing is challenging in patients with chronic obstructive pulmonary disease (COPD. Functional capacity is generally decreased in this patient population, limiting patients' ability to achieve physiologic stress through exercise. Additionally, due to emphysematous changes, COPD patients tend to have poor acoustic windows that impair the quality and therefore diagnostic accuracy of stress echocardiography techniques. Pharmacologic stress myocardial perfusion imaging (MPI testing is also problematic, particularly due to the concern for adenosine-induced bronchoconstriction with conventional vasodilator stress agents. Regadenoson, a selective A2A adenosine receptor agonist, has gained popularity due to its ease of administration and improved patient experience in the general population. The literature describing the experience with regadenoson in COPD patients, though limited, is rapidly growing and reassuring. This review summarizes the pharmacology and clinical application of this novel stress agent and presents the available data on the safety and tolerability of its use in COPD patients.Keywords: chronic obstructive pulmonary disease, COPD, regadenoson, myocardial perfusion imaging, safety, tolerability, asthma, emphysema

  1. Nitric oxide in plants: an assessment of the current state of knowledge

    DEFF Research Database (Denmark)

    Mur, Luis A J; Mandon, Julien; Persijn, Stefan

    2013-01-01

    . By considering the recent advances in plant NO biology, this review will highlight certain key aspects that require further attention. Scope and conclusions The following questions will be considered. Whilst cytosolic nitrate reductase is an important source of NO, the contributions of other mechanisms...... of NO production from DEANO (diethylamine nitric oxide), S-nitrosoglutathione (GSNO) and sodium nitroprusside (SNP) following infiltration of tobacco leaves which could aid workers in their experiments. Further, based on current data it is difficult to define a bespoke plant NO signalling pathway, but rather...

  2. Family planning knowledge and current use of contraception among the Mru indigenous women in Bangladesh: a multivariate analysis

    Directory of Open Access Journals (Sweden)

    Islam MR

    2012-02-01

    Full Text Available M Rakibul Islam1, Gunnar Thorvaldsen21Bangladesh Agricultural University, Bangladesh; 2Norwegian Historical Data Centre, University of Tromsø, NorwayBackground: This article aims to understand the family planning (FP knowledge and current use of contraception and its predictors among women of the Mru people – the most underprivileged indigenous community in Bangladesh.Methods: In this study, 374 currently married Mru women were interviewed and selected purposively from three upazilas (administrative subdistricts of the Bandarban area, where most of the Mru people live. The association between the variables was assessed in bivariate analysis using the Chi-square test and binary logistic regression models were employed to explore the predictors of FP knowledge and current use of contraception among the Mru women.Results: Only about 40% of respondents had ever heard FP messages or about FP methods – two-fifths of the national figure (99.9%. The current use of contraception was much lower (25.1% among the Mru people than at the national level (55.8%. Among both modern and traditional methods, the contraceptive pill ranked first. About two-thirds (66.0% of married women used this method – more than two times than the national figure (28.5%. On the other hand, the prevalence of male methods was comparatively lower than at the national level. Logistic regression models revealed that place of residence, religion, age, school attendance, husband's school attendance, service provided in the community, distance to the service center, and exposure to mass media had significant effects on knowledge of FP and on use of contraception.Conclusion: Education for mothers and vernacular language-based doorstep FP programs with special emphasis on awareness are suggested for the community.Keywords: family planning, contraceptive use, the Mru, logistic regression, Bangladesh

  3. A Survey of Current Knowledge on Sexually Transmitted Diseases and Sexual Behaviour in Italian Adolescents.

    Science.gov (United States)

    Drago, Francesco; Ciccarese, Giulia; Zangrillo, Francesca; Gasparini, Giulia; Cogorno, Ludovica; Riva, Silvia; Javor, Sanja; Cozzani, Emanuele; Broccolo, Francesco; Esposito, Susanna; Parodi, Aurora

    2016-04-13

    Worldwide, 500 million people a year acquire a sexually transmitted disease (STD). Adolescents, accounting for 25% of the sexually active population, are the most affected. To analyze sexual behavior among Italian adolescents and their knowledge of STDs, with the goal of preventing their transmission, a questionnaire was administered to 2867 secondary school students (1271 males and 1596 females) aged 14-21 years. For the study, 1492 students were interviewed in Genoa (Northern Italy) and 1375 in Lecce (Southern Italy). For 37% of the respondents, parents and teachers were the main source of information on sex, and 95% believed that school should play the primary role in sex education. However, only 9% considered the sex education they received in school good. Noteworthy, only 0.5% of the teenagers recognized the sexually transmitted diseases from a list of diseases, and 54% of them did not know what a Pap test was. Confusion about the meaning of contraception and prevention was evident; only 22% knew that condoms and abstinence are the only methods for preventing STDs. Finally, a consistent number of students are exposed to risk factors for STDs transmission; e.g., alcohol and recreational drug use, promiscuity and improper condom use. On the basis of our study, there is an urgent need for the introduction of sex education as a proper subject in Italian schools.

  4. Historical first descriptions of Cajal-Retzius cells: from pioneer studies to current knowledge

    Directory of Open Access Journals (Sweden)

    Vanessa eGil

    2014-05-01

    Full Text Available Santiago Ramón y Cajal developed a great body of scientific research during the last decade of 19th century, mainly between 1888 and 1892, when he published more than 30 manuscripts. The neuronal theory, the structure of dendrites and spines, and fine microscopic descriptions of numerous neural circuits are among these studies. In addition, numerous cell types (neuronal and glial were described by Ramón y Cajal during this time using this ‘reazione nera’ or Golgi method. Among these neurons were the special cells of the molecular layer of the neocortex. These cells were also termed Cajal cells or Retzius cells by other colleagues. Today these cells are known as Cajal-Retzius cells. From the earliest description, several biological aspects of these fascinating cells have been analyzed (e.g., cell morphology, physiological properties, origin and cellular fate, putative function during cortical development, etc. In this review we will summarize in a temporal basis the emerging knowledge concerning this cell population with specific attention the pioneer studies of Santiago Ramón y Cajal.

  5. Current knowledge of prenatal diagnosis of mosaic autosomal trisomy in amniocytes: karyotype/phenotype correlations.

    Science.gov (United States)

    Wallerstein, Robert; Misra, Sonya; Dugar, R Bryce; Alem, Monika; Mazzoni, Ronit; Garabedian, Matthew J

    2015-09-01

    Genetic counseling for prenatal diagnosis of autosomal trisomy is complex because of the uncertainty of outcome, which is important for management decisions. Compilation of cases of prenatally diagnosed autosomal trisomies in amniocytes has been done previously in an attempt to elucidate the clinical phenotype of these pregnancies. It has been greater than a decade since these studies were completed. To update this work, we reviewed cases reported in the literature since that time. These cases are correlated with the prior reports to increase knowledge about outcomes and to hopefully improve the data available for genetic counseling. The risk of abnormal outcome can be summarized as: very high risk (>60%) for 47,+2/46; 47,+9/46; 47,+16/46; 47,+20/46; and 47,+22/46; high risk (40-59%) for 47,+5/46; 47,+14/46; and 47,+15/46; moderately high risk (20-39%) for 47,+7/46 47,+12/46; and 47,+17/46; moderate risk (up to 19%) for 47,+6/46 and 47,+8/46, and none were low risk. 47,+6/46 was originally indeterminate, 47,+7/46 was originally moderate risk, 47,+9/46 was originally high risk, and 47,+17/46 was originally low risk. © 2015 John Wiley & Sons, Ltd.

  6. Current knowledge of environmental exposure in children during the sensitive developmental periods

    Directory of Open Access Journals (Sweden)

    Norma Helena Perlroth

    Full Text Available Abstract: Objective: This study aims to identify the scientific evidence on the risks and effects of exposure to environmental contaminants in children during sensitive developmental periods. Data source: The search was performed in the Bireme database, using the terms: children's health, environmental exposure, health vulnerability, toxicity pathways and developmental disabilities in the LILACS, MEDLINE and SciELO systems. Data synthesis: Children differ from adults in their unique physiological and behavioral characteristics and the potential exposure to risks caused by several threats in the environment. Exposure to toxic agents is analyzed through toxicokinetic processes in the several systems and organs during the sensitive phases of child development. The caused effects are reflected in the increased prevalence of congenital malformations, diarrhea, asthma, cancer, endocrine and neurological disorders, among others, with negative impacts throughout adult life. Conclusion: To identify the causes and understand the mechanisms involved in the genesis of these diseases is a challenge for science, as there is still a lack of knowledge on children's susceptibility to many environmental contaminants. Prevention policies and more research on child environmental health, improving the recording and surveillance of environmental risks to children's health, should be an ongoing priority in the public health field.

  7. A Survey of Current Knowledge on Sexually Transmitted Diseases and Sexual Behaviour in Italian Adolescents

    Directory of Open Access Journals (Sweden)

    Francesco Drago

    2016-04-01

    Full Text Available Worldwide, 500 million people a year acquire a sexually transmitted disease (STD. Adolescents, accounting for 25% of the sexually active population, are the most affected. To analyze sexual behavior among Italian adolescents and their knowledge of STDs, with the goal of preventing their transmission, a questionnaire was administered to 2867 secondary school students (1271 males and 1596 females aged 14–21 years. For the study, 1492 students were interviewed in Genoa (Northern Italy and 1375 in Lecce (Southern Italy. For 37% of the respondents, parents and teachers were the main source of information on sex, and 95% believed that school should play the primary role in sex education. However, only 9% considered the sex education they received in school good. Noteworthy, only 0.5% of the teenagers recognized the sexually transmitted diseases from a list of diseases, and 54% of them did not know what a Pap test was. Confusion about the meaning of contraception and prevention was evident; only 22% knew that condoms and abstinence are the only methods for preventing STDs. Finally, a consistent number of students are exposed to risk factors for STDs transmission; e.g., alcohol and recreational drug use, promiscuity and improper condom use. On the basis of our study, there is an urgent need for the introduction of sex education as a proper subject in Italian schools.

  8. AmpaCity Project - World's First Superconducting Cable and Fault Current Limiter Installation in a German City Center

    Science.gov (United States)

    Stemmle, Mark; Merschel, Frank; Noe, Mathias

    This chapter will give an overview on the German AmpaCity project, which started in September 2011. The objective of the project is developing, manufacturing and installing a 10 kV, 40MVA HTS system consisting of a fault current limiter and of a 1 km cable in the city of Essen. It is the first time that a one kilometer HTS cable system is installed together with an HTS fault current limiter in a real grid application. In addition, it is the longest installed HTS cable system worldwide. Within the project the development phase was finished in March 2013 with successfully completing the type test of the cable system. Subsequently, all system components were manufactured for the installation on site in Essen. The installation took less than three months finishing at the end of November 2013. Afterwards, the commissioning test of the system was performed in December and the system was finally commissioned beginning of 2014.

  9. Fault ride-through enhancement of fixed speed wind turbine using bridge-type fault current limiter

    Directory of Open Access Journals (Sweden)

    Mostafa I. Marei

    2016-05-01

    Full Text Available The interaction between wind energy turbines and the grid results in two main problems, increasing the short-circuit level and reducing the Fault Ride-Through (FRT capability during faults. The objective of this paper is to solve these problems, for fixed speed Wind Energy Systems (WECS, utilizing the bridge-type Fault Current Limiter (FCL with a discharging resistor. A simple cascaded control system is proposed for the FCL to regulate the terminal voltage of the generator and limit the current. The system is simulated on PSCAD/EMTDC software to evaluate the dynamic performance of the proposed WECS compensated by FCL. The simulation results show the potentials of the FCL as a simple and effective method for solving grid interconnection problems of WECS.

  10. A European Perspective on Auditory Processing Disorder-Current Knowledge and Future Research Focus

    Science.gov (United States)

    Iliadou, Vasiliki (Vivian); Ptok, Martin; Grech, Helen; Pedersen, Ellen Raben; Brechmann, André; Deggouj, Naïma; Kiese-Himmel, Christiane; Śliwińska-Kowalska, Mariola; Nickisch, Andreas; Demanez, Laurent; Veuillet, Evelyne; Thai-Van, Hung; Sirimanna, Tony; Callimachou, Marina; Santarelli, Rosamaria; Kuske, Sandra; Barajas, Jose; Hedjever, Mladen; Konukseven, Ozlem; Veraguth, Dorothy; Stokkereit Mattsson, Tone; Martins, Jorge Humberto; Bamiou, Doris-Eva

    2017-01-01

    Current notions of “hearing impairment,” as reflected in clinical audiological practice, do not acknowledge the needs of individuals who have normal hearing pure tone sensitivity but who experience auditory processing difficulties in everyday life that are indexed by reduced performance in other more sophisticated audiometric tests such as speech audiometry in noise or complex non-speech sound perception. This disorder, defined as “Auditory Processing Disorder” (APD) or “Central Auditory Processing Disorder” is classified in the current tenth version of the International Classification of diseases as H93.25 and in the forthcoming beta eleventh version. APDs may have detrimental effects on the affected individual, with low esteem, anxiety, and depression, and symptoms may remain into adulthood. These disorders may interfere with learning per se and with communication, social, emotional, and academic-work aspects of life. The objective of the present paper is to define a baseline European APD consensus formulated by experienced clinicians and researchers in this specific field of human auditory science. A secondary aim is to identify issues that future research needs to address in order to further clarify the nature of APD and thus assist in optimum diagnosis and evidence-based management. This European consensus presents the main symptoms, conditions, and specific medical history elements that should lead to auditory processing evaluation. Consensus on definition of the disorder, optimum diagnostic pathway, and appropriate management are highlighted alongside a perspective on future research focus.

  11. Improving medical students' knowledge of genetic disease: a review of current and emerging pedagogical practices

    Directory of Open Access Journals (Sweden)

    Wolyniak MJ

    2015-10-01

    Full Text Available Michael J Wolyniak,1 Lynne T Bemis,2 Amy J Prunuske2 1Department of Biology, Hampden-Sydney College, Hampden-Sydney, VA, 2Department of Biomedical Sciences, University of Minnesota Medical School, Duluth, MN, USA Abstract: Genetics is an essential subject to be mastered by health professional students of all types. However, technological advances in genomics and recent pedagogical research have changed the way in which many medical training programs teach genetics to their students. These advances favor a more experience-based education focused primarily on developing student's critical thinking skills. In this review, we examine the current state of genetics education at both the preclinical and clinical levels and the ways in which medical and pedagogical research have guided reforms to current and emerging teaching practices in genetics. We discover exciting trends taking place in which genetics is integrated with other scientific disciplines both horizontally and vertically across medical curricula to emphasize training in scientific critical thinking skills among students via the evaluation of clinical evidence and consultation of online databases. These trends will produce future health professionals with the skills and confidence necessary to embrace the new tools of medical practice that have emerged from scientific advances in genetics, genomics, and bioinformatics. Keywords: genetics education, medical genetics, pedagogical practice, active learning, problem-based learning

  12. Reviewing current knowledge in snatch performance and technique: the need for future directions in applied research.

    Science.gov (United States)

    Ho, Lester K W; Lorenzen, Christian; Wilson, Cameron J; Saunders, John E; Williams, Morgan D

    2014-02-01

    This is a review of current research trends in weightlifting literature relating to the understanding of technique and its role in successful snatch performance. Reference to the world records in the snatch from the 1960s onwards indicates little progress across all weight categories. With such mediocre advances in performance at the International level, there is a need to better understand how snatch technique can improve performance even if only by a small margin. Methods of data acquisition for technical analysis of the snatch have involved mostly 2-dimensional barbell and joint kinematics. Although key variables which play a role in the successful outcome of a snatch lift have been heavily investigated, few studies have combined variables relating both the barbell and the weightlifter in their analyses. This suggests the need for a more detailed approach integrating both barbell-related and weightlifter-related data to enhance understanding of the mechanics of a successful lift. Currently, with the aid of technical advances in motion analysis, data acquisition, and methods of analysis, a more accurate representation of the movement can be provided. Better ways of understanding the key characteristics of technique in the snatch could provide the opportunity for more effective individualized feedback from the coach to the athlete, which should in turn lead to improved performance in competition.

  13. A European Perspective on Auditory Processing Disorder-Current Knowledge and Future Research Focus

    Directory of Open Access Journals (Sweden)

    Vasiliki (Vivian Iliadou

    2017-11-01

    Full Text Available Current notions of “hearing impairment,” as reflected in clinical audiological practice, do not acknowledge the needs of individuals who have normal hearing pure tone sensitivity but who experience auditory processing difficulties in everyday life that are indexed by reduced performance in other more sophisticated audiometric tests such as speech audiometry in noise or complex non-speech sound perception. This disorder, defined as “Auditory Processing Disorder” (APD or “Central Auditory Processing Disorder” is classified in the current tenth version of the International Classification of diseases as H93.25 and in the forthcoming beta eleventh version. APDs may have detrimental effects on the affected individual, with low esteem, anxiety, and depression, and symptoms may remain into adulthood. These disorders may interfere with learning per se and with communication, social, emotional, and academic-work aspects of life. The objective of the present paper is to define a baseline European APD consensus formulated by experienced clinicians and researchers in this specific field of human auditory science. A secondary aim is to identify issues that future research needs to address in order to further clarify the nature of APD and thus assist in optimum diagnosis and evidence-based management. This European consensus presents the main symptoms, conditions, and specific medical history elements that should lead to auditory processing evaluation. Consensus on definition of the disorder, optimum diagnostic pathway, and appropriate management are highlighted alongside a perspective on future research focus.

  14. Improving medical students' knowledge of genetic disease: a review of current and emerging pedagogical practices.

    Science.gov (United States)

    Wolyniak, Michael J; Bemis, Lynne T; Prunuske, Amy J

    2015-01-01

    Genetics is an essential subject to be mastered by health professional students of all types. However, technological advances in genomics and recent pedagogical research have changed the way in which many medical training programs teach genetics to their students. These advances favor a more experience-based education focused primarily on developing student's critical thinking skills. In this review, we examine the current state of genetics education at both the preclinical and clinical levels and the ways in which medical and pedagogical research have guided reforms to current and emerging teaching practices in genetics. We discover exciting trends taking place in which genetics is integrated with other scientific disciplines both horizontally and vertically across medical curricula to emphasize training in scientific critical thinking skills among students via the evaluation of clinical evidence and consultation of online databases. These trends will produce future health professionals with the skills and confidence necessary to embrace the new tools of medical practice that have emerged from scientific advances in genetics, genomics, and bioinformatics.

  15. Nanofabrication of Arrays of Silicon Field Emitters with Vertical Silicon Nanowire Current Limiters and Self-Aligned Gates

    Science.gov (United States)

    2016-08-19

    surrounds the nanowires . After the deposition of the dielectric stack, a self-aligned polysilicon gate is defined. A timed etch of the nitride is performed... tunneling through the sur- face barrier . Small deviations from a linear relationship could be due to quantum effects in the emitter tip [33], a non...triangular tunneling barrier due to emitter geometry, or space charge limitation following Child’s law [34]. The saturation of the anode current observed in

  16. Strongylophthalmyiidae, Tanypezidae and Megamerinidae (Diptera in the Czech Republic and Slovakia: current state of knowledge

    Directory of Open Access Journals (Sweden)

    Roháček Jindřich

    2016-03-01

    Full Text Available A review of the occurrence of representatives of the families Strongylophthalmyiidae, Tanypezidae and Megamerinidae (Diptera in the Czech Republic and Slovakia is presented based on literary data and recently obtained records. Strongylophthalmyia pictipes Frey, 1935 (Strongylophthalmyiidae is a new addition to the fauna of the Czech Republic. Its record from the Jizerské hory Mts is the second from Central Europe and represents a new southwestern most distribution limit of the species. Biology, distribution, faunistics in the Czech Republic and Slovakia and importance for nature conservation (with evaluation of degree of jeopardy are discussed for all species, including also Strongylophthalmyia ustulata (Zetterstedt, 1847, Tanypeza longimana Fallén, 1820 (Tanypezidae and Megamerina dolium (Fabricius, 1805 (Megamerinidae.

  17. The Search for Life on Mars - Current Knowledge, Earth Analogues, and Principal Issues

    Science.gov (United States)

    Mumma, Michael J.

    2012-01-01

    For centuries, the planet Mars has been imagined as a possible abode for life. Serious searches for life's signatures began in the 19th century via ground-based visual astronomy that stimulated a vibrant fantasy literature but little lasting scientific knowledge. Modern scientific inquiry has emphasized the search for chemical signatures of life in the soil and rocks at the planet's surface, and via biomarker gases in the atmosphere. Today, investigations are based on high-resolution spectroscopy at Earth's largest telescopes along with planet orbiting and landed space missions. Methane has assumed central importance in these searches. Living systems produce more than 900/0 of Earth's atmospheric methane; the balance is of geochemical origin. Abundant methane is not expected in an oxidizing atmosphere such as Mars', and its presence would imply recent release - whether biological or geochemical. F or that reason, the quest for methane on Mars has been a continuing thread in the fabric of searches conducted since 1969. I will review aspects of the discovery and distribution of methane on Mars, and will mention ongoing extended searches for clues to its origin and destruction. On Earth, hydrogen (generated via serpentinization or radiolysis of water) provides an important 'fuel' for carbonate-reducing and sulphate-reducing biota (CH4 and H2S producers, respectively). Several such communities are known to reside at depth in continental domains (e.g., Lidy Hot Springs, Idaho; Witwatersrand Basin, S. Africa). If similar conditions exist in favourable locations on Mars, organisms similar to these could likely prosper there. Geologic (abiotic) production will also be mentioned, especially abiotic methane production associated with low-temperature serpentinization (e.g., terrestrial ophiolites). It is vitally important to pursue evidence for geochemical and biological production with equal vigour and intellectual weight lest unwanted and unintended bias contaminate the

  18. Heat waves and morbidity: current knowledge and further direction-a comprehensive literature review.

    Science.gov (United States)

    Li, Mengmeng; Gu, Shaohua; Bi, Peng; Yang, Jun; Liu, Qiyong

    2015-05-18

    In the past few decades, several devastating heat wave events have significantly challenged public health. As these events are projected to increase in both severity and frequency in the future, it is important to assess the relationship between heat waves and the health indicators that can be used in the early warning systems to guide the public health response. Yet there is a knowledge gap in the impact of heat waves on morbidity. In this study, a comprehensive review was conducted to assess the relationship between heat waves and different morbidity indicators, and to identify the vulnerable populations. The PubMed and ScienceDirect database were used to retrieve published literature in English from 1985 to 2014 on the relationship between heat waves and morbidity, and the following MeSH terms and keywords were used: heat wave, heat wave, morbidity, hospital admission, hospitalization, emergency call, emergency medical services, and outpatient visit. Thirty-three studies were included in the final analysis. Most studies found a short-term negative health impact of heat waves on morbidity. The elderly, children, and males were more vulnerable during heat waves, and the medical care demand increased for those with existing chronic diseases. Some social factors, such as lower socioeconomic status, can contribute to heat-susceptibility. In terms of study methods and heat wave definitions, there remain inconsistencies and uncertainties. Relevant policies and guidelines need to be developed to protect vulnerable populations. Morbidity indicators should be adopted in heat wave early warning systems in order to guide the effective implementation of public health actions.

  19. Out-of-hospital pediatric cardiac arrest: an epidemiologic review and assessment of current knowledge.

    Science.gov (United States)

    Donoghue, Aaron J; Nadkarni, Vinay; Berg, Robert A; Osmond, Martin H; Wells, George; Nesbitt, Lisa; Stiell, Ian G

    2005-12-01

    We systematically summarize pediatric out-of-hospital cardiac arrest epidemiology and assess knowledge of effects of specific out-of-hospital interventions. We conducted a comprehensive review of published articles from 1966 to 2004, available through MEDLINE, Cumulative Index to Nursing and Allied Health Literature, EmBase, and the Cochrane Registry, describing outcomes of children younger than 18 years with an out-of-hospital cardiac arrest. Patient characteristics, process of care, and outcomes were compared using pediatric Utstein outcome report guidelines. Effects of out-of-hospital care processes on survival outcomes were summarized. Forty-one studies met inclusion criteria; 8 complied with Utstein reporting guidelines. Included in the review were 5,363 patients: 12.1% survived to hospital discharge, and 4% survived neurologically intact. Trauma patients (n=2,299) had greater overall survival (21.9%, 6.8% intact); a separate examination of studies with more rigorous cardiac arrest definition showed poorer survival (1.1% overall, 0.3% neurologically intact). Submersion injury-associated arrests (n=442) had greater overall survival (22.7%, 6% intact). Pooled data analysis of bystander cardiopulmonary resuscitation and witnessed arrest status showed increased likelihood of survival (relative risk 1.99, 95% confidence interval 1.54 to 2.57) for witnessed arrests. The effect of bystander cardiopulmonary resuscitation is difficult to determine because of study heterogeneity. Outcomes from out-of-hospital pediatric cardiac arrest are generally poor. Variability may exist in survival by patient subgroups, but differences are hard to accurately characterize. Conformity with Utstein guidelines for reporting and research design is incomplete. Witnessed arrest status remains associated with improved survival. The need for prospective controlled trials remains a high priority.

  20. How can countries achieve sustainable food supply in 2050: current knowledge and way forward

    Science.gov (United States)

    Kummu, M.; Fader, M.; Gerten, D.; Guillaume, J. H. A.; Jalava, M.; Jägermeyr, J.; Pfister, S.; Porkka, M.; Siebert, S.; Varis, O.

    2016-12-01

    urgent need to integrate these, and other potential measures, together and deepen the knowledge of their combined impact on future sustainable food supply.

  1. Current knowledge and future research perspectives on cassava (Manihot esculenta Crantz) chemical defenses: An agroecological view.

    Science.gov (United States)

    Pinto-Zevallos, Delia M; Pareja, Martín; Ambrogi, Bianca G

    2016-10-01

    Cassava (Manihot esculenta Crantz) is one of the most important staple crops worldwide. It constitutes the major source of carbohydrates for millions of low-income people living in rural areas, as well as a cash crop for smallholders in tropical and sub-tropical regions. The Food and Agriculture Organization of the United Nations predicts that cassava plantations will increase and production systems will intensify in the future, highlighting the need for developing strategies that improve the sustainability of production. Plant chemical defenses hold the potential for developing pest management strategies, as these plant traits can influence the behavior and performance of both pests and beneficial arthropods. Cassava plants are well-defended and produce a number of compounds involved in direct defense, such as cyanogenic glycosides, flavonoid glycosides, and hydroxycoumarins. In addition, volatile organic compounds induced upon herbivory and the secretion of extrafloral nectar act as indirect defense against herbivores by recruiting natural enemies. Here, cassava chemical defenses against pest arthropods are reviewed, with the aim of identifying gaps in our knowledge and areas of research that deserve further investigation for developing sound pest control strategies to improve sustainable production of this crop, and how these defenses can be used to benefit other crops. Cyanogenic content in cassava is also highly toxic to humans, and can cause irreversible health problems even at sub-lethal doses when consumed over prolonged periods. Therefore, the promotion of chemical defense in this crop should not aggravate these problems, and must be accompanied with the education on processing methods that reduce human exposure to cyanide. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. [Pathological buying. A review of the current knowledge regarding this condition of behavioral excess].

    Science.gov (United States)

    Müller, A; de Zwaan, M

    2010-04-01

    Compulsive buying is characterized by frequent excessive purchasing of items that are primarily not needed or used. The compulsive buying behavior results in mental, social, financial and often legal problems. Although compulsive buying affects a significant percentage of the general population and has received increasing attention in research, it has largely been ignored in clinical practice. Compulsive buying disorder is currently conceptualized as an"impulse control disorder not otherwise specified". However, the appropriate classification continues to be debated. Compulsive buying is associated with significant psychiatric co-morbidity, especially with depressive, anxiety, obsessive-compulsive, substance use, personality, and other impulse control disorders. Small controlled trials failed to confirm the efficacy of antidepressants in the treatment of compulsive buying disorder, whereas early evidence suggests that cognitive behavioral therapy is helpful in alleviating compulsive buying symptoms. Further research is needed to establish a better understanding of etiology, classification, and treatment strategies.

  3. Work-related musculoskeletal disorders in nursing: current knowledge and ongoing challenges for occupational health.

    Science.gov (United States)

    Serranheira, Florentino; Smith, Derek

    2014-07-15

    Work-related Musculoskeletal Disorders (MSD) represent a major occupational health concern when considering the relationships between work and disease but associations between MSD and hospital work, especially in the nursing profession, aren't yet full understanded.QMSDuestions that still need to be answered include: Are nurses' work-related musculoskeletal symptoms and injuries dependent on the wards, the hospital organization and even the national occupational health policies that they originated from? Is their MSD related with workplaces demands, equipment, and nurse-patient ratios? Do these factors highlight different nursing occupational exposure to MSD hazards? What are the individual and psychosocial contributes to nurses WRMSDs in different nursing contexts? As such, a new approach which integrates more realistic working conditions, real hospital equipment, workplace features, and individual information would likely be a better way forwards in the addressing the current MSD epidemic among hospital nurses, worldwide......

  4. Chemical pollution in the Arctic and Sub-Arctic marine ecosystems: an overview of current knowledge

    Energy Technology Data Exchange (ETDEWEB)

    Savinova, T.N.; Gabrielsen, G.W.; Falk-Petersen, S.

    1995-02-01

    This report is part of a research project in the framework of the Norwegian-Russian Environmental Cooperation, which was initiated in 1991 to elucidate the present status of environmental contaminants in the highly sensitive Arctic aquatic ecosystem, with special focus on sea birds. Although these ecosystems are the least polluted areas in the world, they are contaminated. The main pathways of contamination into Arctic and sub-Arctic marine ecosystems are atmospheric transport, ocean currents and rivers and in some areas, dumping and ship accidents. A literature survey reveals: (1) there is a lack of data from several trophic levels, (2) previous data are difficult to compare with recent data because of increased quality requirement, (3) not much has been done to investigate the effects of contaminants on the cellular level, at individual or population levels. 389 refs., 7 figs., 32 tabs.

  5. Mars atmospheric losses induced by the solar wind: current knowledge and perspective

    Science.gov (United States)

    Ermakov, Vladimir; Zelenyi, Lev; Vaisberg, Oleg; Sementsov, Egor; Dubinin, Eduard

    2017-04-01

    Solar wind induced atmospheric losses have been studied since earlier 1970th. Several loss channels have been identified including pick-up of exospheric photo-ions and ionospheric ions escape. Measurements performed during several solar cycles showed variation of these losses by about factor of 10, being largest at maximum solar activity. MAVEN spacecraft equipped with comprehensive set of instruments with high temporal and mass resolution operating at Mars since fall 2014 ensures much better investigation of solar wind enforcing Martian environment, Mars atmospheric losses processes and mass loss rate. These issues are very important for understanding of Martian atmospheric evolution including water loss during cosmogonic time. Simultaneous observations by MAVEN and MEX spacecraft open the new perspective in study of Martian environment. In this report we discuss results of past and current missions and preliminary analysis of heavy ions escape using simultaneous measurements of MEX and MAVEN spacecraft.

  6. Knowledge of Ebola virus disease: An evaluation of university students and staff regarding the current Ebola issue around the globe

    Directory of Open Access Journals (Sweden)

    Usman Abubakar

    2015-01-01

    Full Text Available Background: Ebola virus disease (EVD is at the moment a global pandemic disease. The importance of public awareness and alertness toward the disease cannot be underestimated since it is an important step to prevent unnecessary anxiety, fear, as well as an excessive reaction that accompany such anxiety. The main objective of this study is to assess the current level of knowledge and perception of students and staff at Universiti Sains Malaysia toward EVD. Method: A cross sectional survey method was used, and a self-administered questionnaire was used as an instrument for data collection. The questionnaire consisted of three sections. Section A with 6 questions pertaining to demographic data of respondents′, Section B had 20 questions pertaining to respondents knowledge of cause, symptoms, transmission, prevention, and current affairs about EVD. Section C had 12 questions pertaining to respondents′ perception toward EVD. Respondents in this study included both students and staff. Results: From the 520 questionnaire (400 among students and 120 among staff distributed, only 458 were retrieved (380 from students and 78 from staff. Results showed that majority of the students were female (163; 66.0% for undergraduates, 71; 53.4% for postgraduate and 50; 64.1% for staff. The majority of the students first learned about EVD from the internet (193, 80.4%; 102, 81.0%; and 43, 58.9%, respectively, for undergraduate, postgraduate, and staff. This study found that the current level of knowledge about EVD among respondents is low (median knowledge score <50%. However, postgraduate students possess more knowledge than undergraduate and staff (median score 46.2%, P = 0.002. In addition, staff respondents from the university hospital (clinic were found to possess more knowledge than other category of staff (median score = 61.5%, P = 0.002. Furthermore, sciences based students were found to have more knowledge than arts and social sciences based students

  7. Nitric oxide in plants: an assessment of the current state of knowledge

    Science.gov (United States)

    Mur, Luis A. J.; Mandon, Julien; Persijn, Stefan; Cristescu, Simona M.; Moshkov, Igor E.; Novikova, Galina V.; Hall, Michael A.; Harren, Frans J. M.; Hebelstrup, Kim H.; Gupta, Kapuganti J.

    2012-01-01

    Background and aims After a series of seminal works during the last decade of the 20th century, nitric oxide (NO) is now firmly placed in the pantheon of plant signals. Nitric oxide acts in plant–microbe interactions, responses to abiotic stress, stomatal regulation and a range of developmental processes. By considering the recent advances in plant NO biology, this review will highlight certain key aspects that require further attention. Scope and conclusions The following questions will be considered. While cytosolic nitrate reductase is an important source of NO, the contributions of other mechanisms, including a poorly defined arginine oxidizing activity, need to be characterized at the molecular level. Other oxidative pathways utilizing polyamine and hydroxylamine also need further attention. Nitric oxide action is dependent on its concentration and spatial generation patterns. However, no single technology currently available is able to provide accurate in planta measurements of spatio-temporal patterns of NO production. It is also the case that pharmaceutical NO donors are used in studies, sometimes with little consideration of the kinetics of NO production. We here include in planta assessments of NO production from diethylamine nitric oxide, S-nitrosoglutathione and sodium nitroprusside following infiltration of tobacco leaves, which could aid workers in their experiments. Further, based on current data it is difficult to define a bespoke plant NO signalling pathway, but rather NO appears to act as a modifier of other signalling pathways. Thus, early reports that NO signalling involves cGMP—as in animal systems—require revisiting. Finally, as plants are exposed to NO from a number of external sources, investigations into the control of NO scavenging by such as non-symbiotic haemoglobins and other sinks for NO should feature more highly. By crystallizing these questions the authors encourage their resolution through the concerted efforts of the plant

  8. Stochastic dynamics of extended objects in driven systems II: Current quantization in the low-temperature limit

    Science.gov (United States)

    Catanzaro, Michael J.; Chernyak, Vladimir Y.; Klein, John R.

    2016-12-01

    Driven Langevin processes have appeared in a variety of fields due to the relevance of natural phenomena having both deterministic and stochastic effects. The stochastic currents and fluxes in these systems provide a convenient set of observables to describe their non-equilibrium steady states. Here we consider stochastic motion of a (k - 1) -dimensional object, which sweeps out a k-dimensional trajectory, and gives rise to a higher k-dimensional current. By employing the low-temperature (low-noise) limit, we reduce the problem to a discrete Markov chain model on a CW complex, a topological construction which generalizes the notion of a graph. This reduction allows the mean fluxes and currents of the process to be expressed in terms of solutions to the discrete Supersymmetric Fokker-Planck (SFP) equation. Taking the adiabatic limit, we show that generic driving leads to rational quantization of the generated higher dimensional current. The latter is achieved by implementing the recently developed tools, coined the higher-dimensional Kirchhoff tree and co-tree theorems. This extends the study of motion of extended objects in the continuous setting performed in the prequel (Catanzaro et al.) to this manuscript.

  9. Stochastic Dynamics of Extended Objects in Driven Systems II: Current Quantization in the Low-Temperature Limit

    CERN Document Server

    Catanzaro, Michael J; Klein, John R

    2016-01-01

    Driven Langevin processes have appeared in a variety of fields due to the relevance of natural phenomena having both deterministic and stochastic effects. The stochastic currents and fluxes in these systems provide a convenient set of observables to describe their non-equilibrium steady states. Here we consider stochastic motion of a (k - 1)-dimensional object, which sweeps out a k-dimensional trajectory, and gives rise to a higher k-dimensional current. By employing the low-temperature (low-noise) limit, we reduce the problem to a discrete Markov chain model on a CW complex, a topological construction which generalizes the notion of a graph. This reduction allows the mean fluxes and currents of the process to be expressed in terms of solutions to the discrete Supersymmetric Fokker-Planck (SFP) equation. Taking the adiabatic limit, we show that generic driving leads to rational quantization of the generated higher dimensional current. The latter is achieved by implementing the recently developed tools, coined...

  10. Chemical crosslinking of biopolymeric scaffolds: Current knowledge and future directions of crosslinked engineered bone scaffolds.

    Science.gov (United States)

    Oryan, Ahmad; Kamali, Amir; Moshiri, Ali; Baharvand, Hossien; Daemi, Hamed

    2018-02-01

    Bone tissue scaffolds made from either natural or synthetic polymers are employed to promote bone healing. However, lack of sufficient or poor mechanical properties such as low integrity and stability reduces their medical applications. Crosslinking, defined as induction of chemical or physical links among polymer chains, is a simple method generally used to modify mechanical, biological and degradation properties of hydrogels. Although crosslinking through chemical reactions improves the mechanical properties of bone substitutes, most of the reagents used for this aim demonstrate undesirable effects and may exert toxic reactions. Glutaraldehyde is a widely-used chemical crosslinker with unique ability to crosslink a wide variety of biomaterials; however, many contradictory views have been recently raised on its cytotoxic effects. By keeping this limit in mind, green chemicals or natural crosslinking agents have been shown to provide desired improvements in mechanical properties of bone scaffolds. Therefore, developing more efficient crosslinking materials and methods are desirable to obtain crosslinked scaffolds with perfect properties in bone tissue engineering from different biopolymers such as collagen, gelatin, cellulose, chitosan, alginate, etc. In this review, we focused on developed or developing modalities used to improve mechanical properties of various bone scaffolds and matrices based on common crosslinking reagents. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Indo-Pacific Humpback Dolphins in Borneo: A Review of Current Knowledge with Emphasis on Sarawak.

    Science.gov (United States)

    Minton, Gianna; Zulkifli Poh, Anna Norliza; Peter, Cindy; Porter, Lindsay; Kreb, Danielle

    2016-01-01

    Indo-Pacific humpback dolphins (Sousa chinensis) are documented from various locations along Borneo's coast, including three sites in Sarawak, Malaysia, three sites in Sabah, Malaysia, three locations in Kalimantan, Indonesia and the limited coastal waters of the Sultanate of Brunei. Observations in all these areas indicate a similar external morphology, which seems to fall somewhere between that documented for Chinese populations known as S. chinensis, and that of Sousa sahulensis in Australia and Papua New Guinea. Sightings occur in shallow nearshore waters, often near estuaries and river mouths, and associations with Irrawaddy dolphins (Orcaella brevirostris) are frequently documented. Population estimates exist for only two locations and sightings information throughout Borneo indicates that frequency of occurrence is rare and group size is usually small. Threats from fisheries by-catch and coastal development are present in many locations and there are concerns over the ability of these small and fragmented populations to survive. The conservation and taxonomic status of humpback dolphins in Borneo remain unclear, and there are intriguing questions as to where these populations fit in our evolving understanding of the taxonomy of the genus. © 2016 Elsevier Ltd. All rights reserved.

  12. Advances in Developing Therapies to Combat Zika Virus: Current Knowledge and Future Perspectives

    Science.gov (United States)

    Munjal, Ashok; Khandia, Rekha; Dhama, Kuldeep; Sachan, Swati; Karthik, Kumaragurubaran; Tiwari, Ruchi; Malik, Yashpal S.; Kumar, Deepak; Singh, Raj K.; Iqbal, Hafiz M. N.; Joshi, Sunil K.

    2017-01-01

    Zika virus (ZIKV) remained largely quiescent for nearly six decades after its first appearance in 1947. ZIKV reappeared after 2007, resulting in a declaration of an international “public health emergency” in 2016 by the World Health Organization (WHO). Until this time, ZIKV was considered to induce only mild illness, but it has now been established as the cause of severe clinical manifestations, including fetal anomalies, neurological problems, and autoimmune disorders. Infection during pregnancy can cause congenital brain abnormalities, including microcephaly and neurological degeneration, and in other cases, Guillain-Barré syndrome, making infections with ZIKV a substantial public health concern. Genomic and molecular investigations are underway to investigate ZIKV pathology and its recent enhanced pathogenicity, as well as to design safe and potent vaccines, drugs, and therapeutics. This review describes progress in the design and development of various anti-ZIKV therapeutics, including drugs targeting virus entry into cells and the helicase protein, nucleosides, inhibitors of NS3 protein, small molecules, methyltransferase inhibitors, interferons, repurposed drugs, drugs designed with the aid of computers, neutralizing antibodies, convalescent serum, antibodies that limit antibody-dependent enhancement, and herbal medicines. Additionally, covalent inhibitors of viral protein expression and anti-Toll-like receptor molecules are discussed. To counter ZIKV-associated disease, we need to make rapid progress in developing novel therapies that work effectually to inhibit ZIKV. PMID:28824594

  13. Advances in Developing Therapies to Combat Zika Virus: Current Knowledge and Future Perspectives.

    Science.gov (United States)

    Munjal, Ashok; Khandia, Rekha; Dhama, Kuldeep; Sachan, Swati; Karthik, Kumaragurubaran; Tiwari, Ruchi; Malik, Yashpal S; Kumar, Deepak; Singh, Raj K; Iqbal, Hafiz M N; Joshi, Sunil K

    2017-01-01

    Zika virus (ZIKV) remained largely quiescent for nearly six decades after its first appearance in 1947. ZIKV reappeared after 2007, resulting in a declaration of an international "public health emergency" in 2016 by the World Health Organization (WHO). Until this time, ZIKV was considered to induce only mild illness, but it has now been established as the cause of severe clinical manifestations, including fetal anomalies, neurological problems, and autoimmune disorders. Infection during pregnancy can cause congenital brain abnormalities, including microcephaly and neurological degeneration, and in other cases, Guillain-Barré syndrome, making infections with ZIKV a substantial public health concern. Genomic and molecular investigations are underway to investigate ZIKV pathology and its recent enhanced pathogenicity, as well as to design safe and potent vaccines, drugs, and therapeutics. This review describes progress in the design and development of various anti-ZIKV therapeutics, including drugs targeting virus entry into cells and the helicase protein, nucleosides, inhibitors of NS3 protein, small molecules, methyltransferase inhibitors, interferons, repurposed drugs, drugs designed with the aid of computers, neutralizing antibodies, convalescent serum, antibodies that limit antibody-dependent enhancement, and herbal medicines. Additionally, covalent inhibitors of viral protein expression and anti-Toll-like receptor molecules are discussed. To counter ZIKV-associated disease, we need to make rapid progress in developing novel therapies that work effectually to inhibit ZIKV.

  14. Advances in Developing Therapies to Combat Zika Virus: Current Knowledge and Future Perspectives

    Directory of Open Access Journals (Sweden)

    Ashok Munjal

    2017-08-01

    Full Text Available Zika virus (ZIKV remained largely quiescent for nearly six decades after its first appearance in 1947. ZIKV reappeared after 2007, resulting in a declaration of an international “public health emergency” in 2016 by the World Health Organization (WHO. Until this time, ZIKV was considered to induce only mild illness, but it has now been established as the cause of severe clinical manifestations, including fetal anomalies, neurological problems, and autoimmune disorders. Infection during pregnancy can cause congenital brain abnormalities, including microcephaly and neurological degeneration, and in other cases, Guillain-Barré syndrome, making infections with ZIKV a substantial public health concern. Genomic and molecular investigations are underway to investigate ZIKV pathology and its recent enhanced pathogenicity, as well as to design safe and potent vaccines, drugs, and therapeutics. This review describes progress in the design and development of various anti-ZIKV therapeutics, including drugs targeting virus entry into cells and the helicase protein, nucleosides, inhibitors of NS3 protein, small molecules, methyltransferase inhibitors, interferons, repurposed drugs, drugs designed with the aid of computers, neutralizing antibodies, convalescent serum, antibodies that limit antibody-dependent enhancement, and herbal medicines. Additionally, covalent inhibitors of viral protein expression and anti-Toll-like receptor molecules are discussed. To counter ZIKV-associated disease, we need to make rapid progress in developing novel therapies that work effectually to inhibit ZIKV.

  15. A synthesis of current knowledge on forests and carbon storage in the United States.

    Science.gov (United States)

    McKinley, Duncan C; Ryan, Michael G; Birdsey, Richard A; Giardina, Christian P; Harmon, Mark E; Heath, Linda S; Houghton, Richard A; Jackson, Robert B; Morrison, James F; Murray, Brian C; Patakl, Diane E; Skog, Kenneth E

    2011-09-01

    Using forests to mitigate climate change has gained much interest in science and policy discussions. We examine the evidence for carbon benefits, environmental and monetary costs, risks and trade-offs for a variety of activities in three general strategies: (1) land use change to increase forest area (afforestation) and avoid deforestation; (2) carbon management in existing forests; and (3) the use of wood as biomass energy, in place of other building materials, or in wood products for carbon storage. We found that many strategies can increase forest sector carbon mitigation above the current 162-256 Tg C/yr, and that many strategies have co-benefits such as biodiversity, water, and economic opportunities. Each strategy also has trade-offs, risks, and uncertainties including possible leakage, permanence, disturbances, and climate change effects. Because approximately 60% of the carbon lost through deforestation and harvesting from 1700 to 1935 has not yet been recovered and because some strategies store carbon in forest products or use biomass energy, the biological potential for forest sector carbon mitigation is large. Several studies suggest that using these strategies could offset as much as 10-20% of current U.S. fossil fuel emissions. To obtain such large offsets in the United States would require a combination of afforesting up to one-third of cropland or pastureland, using the equivalent of about one-half of the gross annual forest growth for biomass energy, or implementing more intensive management to increase forest growth on one-third of forestland. Such large offsets would require substantial trade-offs, such as lower agricultural production and non-carbon ecosystem services from forests. The effectiveness of activities could be diluted by negative leakage effects and increasing disturbance regimes. Because forest carbon loss contributes to increasing climate risk and because climate change may impede regeneration following disturbance, avoiding

  16. Etiology and epidemiology of Pythium root rot in hydroponic crops: current knowledge and perspectives

    Directory of Open Access Journals (Sweden)

    John Clifford Sutton

    2006-09-01

    Full Text Available The etiology and epidemiology of Pythium root rot in hydroponically-grown crops are reviewed with emphasis on knowledge and concepts considered important for managing the disease in commercial greenhouses. Pythium root rot continually threatens the productivity of numerous kinds of crops in hydroponic systems around the world including cucumber, tomato, sweet pepper, spinach, lettuce, nasturtium, arugula, rose, and chrysanthemum. Principal causal agents include Pythium aphanidermatum, Pythium dissotocum, members of Pythium group F, and Pythium ultimum var. ultimum. Perspectives are given of sources of initial inoculum of Pythium spp. in hydroponic systems, of infection and colonization of roots by the pathogens, symptom development and inoculum production in host roots, and inoculum dispersal in nutrient solutions. Recent findings that a specific elicitor produced by P. aphanidermatum may trigger necrosis (browning of the roots and the transition from biotrophic to necrotrophic infection are considered. Effects on root rot epidemics of host factors (disease susceptibility, phenological growth stage, root exudates and phenolic substances, the root environment (rooting media, concentrations of dissolved oxygen and phenolic substances in the nutrient solution, microbial communities and temperature and human interferences (cropping practices and control measures are reviewed. Recent findings on predisposition of roots to Pythium attack by environmental stress factors are highlighted. The commonly minor impact on epidemics of measures to disinfest nutrient solution as it recirculates outside the crop is contrasted with the impact of treatments that suppress Pythium in the roots and root zone of the crop. New discoveries that infection of roots by P. aphanidermatum markedly slows the increase in leaf area and whole-plant carbon gain without significant effect on the efficiency of photosynthesis per unit area of leaf are noted. The platform of

  17. Bacterial Diseases of Bananas and Enset: Current State of Knowledge and Integrated Approaches Toward Sustainable Management

    Directory of Open Access Journals (Sweden)

    Guy Blomme

    2017-07-01

    Full Text Available Bacterial diseases of bananas and enset have not received, until recently, an equal amount of attention compared to other major threats to banana production such as the fungal diseases black leaf streak (Mycosphaerella fijiensis and Fusarium wilt (Fusarium oxysporum f. sp. cubense. However, bacteria cause significant impacts on bananas globally and management practices are not always well known or adopted by farmers. Bacterial diseases in bananas and enset can be divided into three groups: (1 Ralstonia-associated diseases (Moko/Bugtok disease caused by Ralstonia solanacearum and banana blood disease caused by R. syzygii subsp. celebesensis; (2 Xanthomonas wilt of banana and enset, caused by Xanthomonas campestris pv. musacearum and (3 Erwinia-associated diseases (bacterial head rot or tip-over disease Erwinia carotovora ssp. carotovora and E. chrysanthemi, bacterial rhizome and pseudostem wet rot (Dickeya paradisiaca formerly E. chrysanthemi pv. paradisiaca. Other bacterial diseases of less widespread importance include: bacterial wilt of abaca, Javanese vascular wilt and bacterial fingertip rot (probably caused by Ralstonia spp., unconfirmed. This review describes global distribution, symptoms, pathogenic diversity, epidemiology and the state of the art for sustainable disease management of the major bacterial wilts currently affecting banana and enset.

  18. Bacterial Diseases of Bananas and Enset: Current State of Knowledge and Integrated Approaches Toward Sustainable Management.

    Science.gov (United States)

    Blomme, Guy; Dita, Miguel; Jacobsen, Kim Sarah; Pérez Vicente, Luis; Molina, Agustin; Ocimati, Walter; Poussier, Stephane; Prior, Philippe

    2017-01-01

    Bacterial diseases of bananas and enset have not received, until recently, an equal amount of attention compared to other major threats to banana production such as the fungal diseases black leaf streak (Mycosphaerella fijiensis) and Fusarium wilt (Fusarium oxysporum f. sp. cubense). However, bacteria cause significant impacts on bananas globally and management practices are not always well known or adopted by farmers. Bacterial diseases in bananas and enset can be divided into three groups: (1) Ralstonia-associated diseases (Moko/Bugtok disease caused by Ralstonia solanacearum and banana blood disease caused by R. syzygii subsp. celebesensis); (2) Xanthomonas wilt of banana and enset, caused by Xanthomonas campestris pv. musacearum and (3) Erwinia-associated diseases (bacterial head rot or tip-over disease Erwinia carotovora ssp. carotovora and E. chrysanthemi), bacterial rhizome and pseudostem wet rot (Dickeya paradisiaca formerly E. chrysanthemi pv. paradisiaca). Other bacterial diseases of less widespread importance include: bacterial wilt of abaca, Javanese vascular wilt and bacterial fingertip rot (probably caused by Ralstonia spp., unconfirmed). This review describes global distribution, symptoms, pathogenic diversity, epidemiology and the state of the art for sustainable disease management of the major bacterial wilts currently affecting banana and enset.

  19. Development and use of microbial-based cleaning products (MBCPs): Current issues and knowledge gaps.

    Science.gov (United States)

    Arvanitakis, George; Temmerman, Robin; Spök, Armin

    2017-12-19

    Cleaning products containing microbes as active ingredients are becoming increasingly prevalent as an alternative to chemical-based cleaning products. These microbial-based cleaning products (MBCPs) are being used in domestic and commercial settings (i.e., households and businesses) and institutional settings (e.g., hospitals, schools, etc.), in a variety of cleaning activities (hard surface cleaning, odour control, degreasing, septic tank treatments, etc.). They are typically described as "environmentally friendly" and "non-toxic". Publicly available information sources (scientific literature, patent databases, commercial websites) were searched for information on microbial species contained in MBCPs, their mode of action, cleaning applications in which they are used, and their potential impacts on human health and the environment. Although information was found providing a broad indication of microbial genera/species used, information on specific species/strains and quantities produced and sold is generally lacking. This makes it difficult to conduct a meaningful examination of any risks to human health and the environment from the production and use of MBCPs and to determine how effective current policies and regulatory frameworks are in addressing these issues. These and other challenges were addressed at an international workshop in Ottawa, Canada in June 2013 by a number of stakeholders, including industry, government, academic and non-governmental organizations. Copyright © 2017. Published by Elsevier Ltd.

  20. Out of sight out of mind: current knowledge of Chinese cave fishes.

    Science.gov (United States)

    Zhao, Y-H; Gozlan, R E; Zhang, C-G

    2011-12-01

    Caves and karsts are among the most threatened ecosystems in the world. They are very fragile, balanced habitats with high levels of endemic species that are extremely sensitive to environmental changes. In recent decades, however, threats from rapid economic growth have increased the need for conservation efforts for cave-dwelling communities. In addition, difficulties in accessing and sampling these habitats mean that they remain as one of the least known ecosystems in the world with modern studies of cave fishes only starting in China during the 1980s. Here, the current status of cave fishes in China is reviewed. China is host to the highest number of cave fish species in the world, with 48 troglobite species out of a total of 101 cave fish species. All of these cave fish species (one order and three families) and half of the genera are endemic to China with Sinocyclocheilus being the most speciose cave fish genus. Species from this genus possess horns and humpbacks resulting from processes of parallel evolution, but the function of these features remains unknown. With the exception of Onychostoma macrolepis distributed in north China, all other species are found in the karst environment of the Yunnan-Guizhou Plateau. Sympatric distribution is common, and sometimes several different cave fish species can be found in the same cave or subterranean river. For this reason, Chinese cave fishes represent an important evolutionary framework. © 2011 The Authors. Journal of Fish Biology © 2011 The Fisheries Society of the British Isles.

  1. Current knowledge on tumour induction by computed tomography should be carefully used

    Energy Technology Data Exchange (ETDEWEB)

    Candela-Juan, Cristian [La Fe University and Polytechnic Hospital, Radioprotection Department, Valencia (Spain); Montoro, Alegria; Villaescusa, Juan Ignacio [La Fe University and Polytechnic Hospital, Radioprotection Department, Valencia (Spain); IIS La Fe, Biomedical Imaging Research Group GIBI230, Valencia (Spain); Ruiz-Martinez, Enrique; Marti-Bonmati, Luis [IIS La Fe, Biomedical Imaging Research Group GIBI230, Valencia (Spain); La Fe University and Polytechnic Hospital, Department of Radiology, Valencia (Spain)

    2014-03-15

    Risks associated to ionising radiation from medical imaging techniques have focused the attention of the medical society and general population. This risk is aimed to determine the probability that a tumour is induced as a result of a computed tomography (CT) examination since it makes nowadays the biggest contribution to the collective dose. Several models of cancer induction have been reported in the literature, with diametrically different implications. This article reviews those models, focusing on the ones used by the scientific community to estimate CT detriments. Current estimates of the probability that a CT examination induces cancer are reported, highlighting its low magnitude (near the background level) and large sources of uncertainty. From this objective review, it is concluded that epidemiological data with more accurate dosimetric estimates are needed. Prediction of the number of tumours that will be induced in population exposed to ionising radiation should be avoided or, if given, it should be accompanied by a realistic evaluation of its uncertainty and of the advantages of CTs. Otherwise they may have a negative impact in both the medical community and the patients. Reducing doses even more is not justified if that compromises clinical image quality in a necessary investigation. (orig.)

  2. Current knowledge of coffee wilt disease, a major constraint to coffee production in Africa.

    Science.gov (United States)

    Rutherford, Mike A

    2006-06-01

    ABSTRACT Coffee is vital to the economy of East and Central Africa, providing a major source of foreign exchange earnings and, as a cash crop, supporting the livelihoods of millions involved in cultivation, processing, marketing, and export. Coffee wilt disease (CWD), attributed to Gibberella xylarioides (Fusarium xylarioides), has caused losses to coffee production in Africa since 1927 but has been largely contained through the use of host resistance and in some instances wide-scale sanitation practices. A reemergence of CWD on Coffea canephora (Robusta coffee) in Uganda, Democratic Republic of Congo, and Tanzania has already led to heavy losses and threatens future production in these countries and elsewhere in the region. The relevance of CWD is all the more pertinent given the impact of a considerable fall in world coffee prices over the last decade. Recent research has clarified the extent of the problem in the region and revealed a low level of diversity within the pathogen, suggesting that two genetically and biologically distinct forms are responsible for current problems. These findings and related research and development initiatives undertaken under the auspices of the Regional Coffee Wilt Programme are of fundamental importance in providing an urgently needed solution to this devastating disease.

  3. Bruxism: overview of current knowledge and suggestions for dental implants planning.

    Science.gov (United States)

    Manfredini, Daniele; Bucci, Marco Brady; Sabattini, Vincenzo Bucci; Lobbezoo, Frank

    2011-10-01

    Bruxism is commonly considered a detrimental motor activity, potentially causing overload of the stomatognathic structures and representing a risk factor for dental implant survival. The available literature does not provide evidence-based guidelines for the management of bruxers undergoing implant-retained restorations. The present paper reviewed current concepts on bruxism etiology, diagnosis and management, underlining its effects on dental implants in an attempt to provide clinically useful suggestions based on scientifically sound data. Unfortunately, very little data exists on the subject of a cause-and-effect relationship between bruxism and implant failure, to the point that expert opinions and cautionary approaches are still considered the best available sources for suggesting good practice indicators. By including experimental literature data on the effects of different types of occlusal loading on peri-implant marginal bone loss along with data from studies investigating the intensity of the forces transmitted to the bone itself during tooth-clenching and tooth-grinding activities, the authors were able to compile the suggestions presented here for prosthetic implant rehabilitations in patients with bruxism.

  4. Bacterial Diseases of Bananas and Enset: Current State of Knowledge and Integrated Approaches Toward Sustainable Management

    Science.gov (United States)

    Blomme, Guy; Dita, Miguel; Jacobsen, Kim Sarah; Pérez Vicente, Luis; Molina, Agustin; Ocimati, Walter; Poussier, Stephane; Prior, Philippe

    2017-01-01

    Bacterial diseases of bananas and enset have not received, until recently, an equal amount of attention compared to other major threats to banana production such as the fungal diseases black leaf streak (Mycosphaerella fijiensis) and Fusarium wilt (Fusarium oxysporum f. sp. cubense). However, bacteria cause significant impacts on bananas globally and management practices are not always well known or adopted by farmers. Bacterial diseases in bananas and enset can be divided into three groups: (1) Ralstonia-associated diseases (Moko/Bugtok disease caused by Ralstonia solanacearum and banana blood disease caused by R. syzygii subsp. celebesensis); (2) Xanthomonas wilt of banana and enset, caused by Xanthomonas campestris pv. musacearum and (3) Erwinia-associated diseases (bacterial head rot or tip-over disease Erwinia carotovora ssp. carotovora and E. chrysanthemi), bacterial rhizome and pseudostem wet rot (Dickeya paradisiaca formerly E. chrysanthemi pv. paradisiaca). Other bacterial diseases of less widespread importance include: bacterial wilt of abaca, Javanese vascular wilt and bacterial fingertip rot (probably caused by Ralstonia spp., unconfirmed). This review describes global distribution, symptoms, pathogenic diversity, epidemiology and the state of the art for sustainable disease management of the major bacterial wilts currently affecting banana and enset. PMID:28785275

  5. Neuropathology of depression in Alzheimer's disease: current knowledge and the potential for new treatments.

    Science.gov (United States)

    Khundakar, Ahmad A; Thomas, Alan J

    2015-01-01

    Depression is among the most common behavioral and psychological symptoms of dementia, and leads to more rapid decline and higher mortality. Treatment for depression in dementia has centered on conventional antidepressant drug treatment based around the monoamine hypothesis of depression. However, recent major studies have suggested that conventional antidepressant treatments that aim to correct underlying deficits in monoamine neurotransmitters are not effective for depression in dementia. Postmortem studies have also suggested that depression in dementia does not arise from serotonergic or noradrenergic abnormalities, or indeed from the degenerative pathology associated with Alzheimer's disease. In contrast, considerable recent evidence has suggested that alterations in glutamatergic transmission may contribute to the pathophysiology of depression. This supports the view that treatment-resistant depressed patients, such as many dementia patients, may benefit from agents affecting glutamate transmission. This review will thus draw together the wealth of pathological data examining the basis of depression in Alzheimer's disease and relate this to current thinking on treatment, with the aim of generating discussion on potential novel therapeutic strategies.

  6. Solid-State Fault Current Limiter Development : Design and Testing Update of a 15kV SSCL Power Stack

    Energy Technology Data Exchange (ETDEWEB)

    Dr. Ram Adapa; Mr. Dante Piccone

    2012-04-30

    ABSTRACT The Solid-State Fault Current Limiter (SSCL) is a promising technology that can be applied to utility power delivery systems to address the problem of increasing fault currents associated with load growth. As demand continues to grow, more power is added to utility system either by increasing generator capacity or by adding distributed generators, resulting in higher available fault currents, often beyond the capabilities of the present infrastructure. The SSCL is power-electronics based equipment designed to work with the present utility system to address this problem. The SSCL monitors the line current and dynamically inserts additional impedance into the line in the event of a fault being detected. The SSCL is based on a modular design and can be configured for 5kV through 69kV systems at nominal current ratings of 1000A to 4000A. Results and Findings This report provides the final test results on the development of 15kV class SSCL single phase power stack. The scope of work included the design of the modular standard building block sub-assemblies, the design and manufacture of the power stack and the testing of the power stack for the key functional tests of continuous current capability and fault current limiting action. Challenges and Objectives Solid-State Current Limiter technology impacts a wide spectrum of utility engineering and operating personnel. It addresses the problems associated with load growth both at Transmission and Distribution class networks. The design concept is pioneering in terms of developing the most efficient and compact power electronics equipment for utility use. The initial test results of the standard building blocks are promising. The independent laboratory tests of the power stack are promising. However the complete 3 phase system needs rigorous testing for performance and reliability. Applications, Values, and Use The SSCL is an intelligent power-electronics device which is modular in design and can provide current

  7. Current state of knowledge: perceptual processing by children with hearing impairment.

    Science.gov (United States)

    Jerger, Susan

    2007-12-01

    Perception concerns the identification and interpretation of sensory stimuli in our external environment. The purpose of this review is to survey contemporary views about effects of mild to severe sensorineural hearing impairment (HI) in children on perceptual processing. The review is one of a series of papers resulting from a workshop on Outcomes Research in Children with Hearing Loss sponsored by The National Institute on Deafness and Other Communication Disorders/National Institutes of Health. Children with HI exhibit heterogeneous patterns of results. In general, however, perceptual processing of the (a) auditory properties of nonspeech reveals some problems in processing spectral information, but not temporal information; (b) auditory properties of speech reveals some problems in processing temporal sequences, variation in spatial location, and voice onset times, but not in processing talker-gender, weighting acoustic cues, or covertly orienting to the spatial location of sound; (c) linguistic properties of speech reveals some problems in processing general linguistic content, semantic content, and phonological content. The normalcy/abnormalcy of results varies as a function of degree of loss and task demands. As a general rule, children with severe HI have more abnormalities than children with mild to moderate HI. Auditory linguistic properties are also generally processed more abnormally than auditory nonverbal properties. This outcome implies that childhood HI has less effect on more physical, developmentally earlier properties that are characterized by less contingent processing. Some perceptual properties that are processed in a more automatic manner by normal listeners are processed in a more controlled manner by children with HI. This outcome implies that deliberate perceptual processing in the presence of childhood HI requires extra effort and more mental resources, thus limiting the availability of processing resources for other tasks.

  8. Current knowledge and importance of dGEMRIC techniques in diagnosis of hip joint diseases

    Energy Technology Data Exchange (ETDEWEB)

    Zilkens, Christoph; Krauspe, Ruediger; Bittersohl, Bernd [University of Duesseldorf, Medical Faculty, Department of Orthopedic Surgery, Duesseldorf (Germany); Tiderius, Carl Johann [Lund University Hospital, Department of Orthopedic Surgery, Lund (Sweden)

    2015-08-15

    Accurate assessment of early hip joint cartilage alterations may help optimize patient selection and follow-up of hip joint preservation surgery. Delayed gadolinium-enhanced magnetic resonance imaging of cartilage (dGEMRIC) is sensitive to the glycosaminoglycan content in cartilage that is lost early in the development of osteoarthritis (OA). Hence, the dGEMRIC technique holds promise for the development of new diagnostic and therapeutic procedures. However, because of the location of the hip joint deep within the body and due to the fairly thin cartilage layers that require high spatial resolution, the diagnosis of early hip joint cartilage alterations may be problematic. The purpose of this review is to outline the current status of dGEMRIC in the assessment of hip joint cartilage. A literature search was performed with PubMed, using the terms ''cartilage, osteoarthritis, hip joint, MRI, and dGEMRIC'', considering all levels of studies. This review revealed that dGEMRIC can be reliably used in the evaluation of early stage cartilage pathology in various hip joint disorders. Modifications in the technique, such as the operation of three-dimensional imaging and dGEMRIC after intra-articular contrast medium administration, have expanded the range of application. Notably, the studies differ considerably in patient selection and technical prerequisites. Furthermore, there is a need for multicenter prospective studies with the required technical conditions in place to establish outcome based dGEMRIC data to obtain, in conjunction with clinical data, reliable threshold values for normal and abnormal cartilage, and for hips that may benefit from conservative or surgical treatment. (orig.)

  9. HONGOS ENDÓFITOS TROPICALES: CONOCIMIENTO ACTUAL Y PERSPECTIVAS Tropical Endophytic Fungi: Current Knowledge and Perspectives

    Directory of Open Access Journals (Sweden)

    MIGUEL A GAMBOAGAITÁN

    Full Text Available Los organismos endófitos, particularmente los hongos, han recibido una creciente atención en los años recientes. Este grupo de microrganismos vive asintomáticamente dentro de tejidos vegetales sanos, y ha mostrado poseer un gran potencial económico en áreas como la agronomía y la medicina. También se han usado como grupo modelo para estudiar aspectos teóricos de la ecología de comunidades y de la interacción planta microorganismo. En la presente revisión se ha recopilado la literatura existente acerca de los hongos endófitos tropicales, y se analiza comparativamente con algunos trabajos de zonas templadas. Se discuten algunos de los aspectos más relevantes y promisorios en este sistema simbiótico y se hacen recomendaciones acerca de tópicos particulares hacia los que debe dirigirse la investigación en este campo.Endophytic microorganisms are symptomless inhabitants of plant tissues. This group is receiving a growing attention due to its potential in fields as varied as agronomy and medicine. Some more basic aspects of science, such as ecology of communities and plantmicrobe interactions have also been studied in this group. This review emphasizes on current literature about tropical endophytes and work in this theme is compared with those developed in temperate zones when appropriate. The most important ecological aspects of this system are discussed, and recommendations about the future directions of research in this field are done, especially those related to the use of endophytes as a model group in modern biology.

  10. Coral-associated bacterial assemblages: current knowledge and the potential for climate-driven impacts.

    Science.gov (United States)

    Mouchka, Morgan E; Hewson, Ian; Harvell, C Drew

    2010-10-01

    The importance of associations between microorganisms and their invertebrate hosts is becoming increasingly apparent. An emerging field, driven by the necessity to understand the microbial relationships that both maximize coral health and cause coral disease, is the study of coral-bacteria interactions. In this article, we review our current understanding of the diversity, specificity, development, and functions of coral-associated bacteria. We also summarize what is known regarding the role of coral microbiota in the health and disease of coral. We conduct a meta-analysis to determine whether the presence of unique taxa correlates with the state of coral health (i.e. healthy, diseased or bleached), as well as whether coral reef habitats harbor clusters of distinct taxa. We find that healthy and bleached corals harbor similar dominant taxa, although bleached corals had higher proportions of Vibrio and Acidobacteria. Diseased corals generally had more Rhodobacter, Clostridia, and Cyanobacteria sequences, and fewer Oceanospirillum sequences. We caution, however, that while 16S rRNA is useful for microbial species identification, it is a poor predictor of habitat or lifestyle, and care should be taken in interpretation of 16S rRNA surveys to identify potential pathogens amongst complex coral-microbial assemblages. Finally, we highlight evidence that coral-bacterial assemblages could be sensitive to the effects of climatic change. We suggest that the relationship between coral and their bacterial associates represents a valuable model that can be applied to the broader discipline of invertebrate-microbial interactions. © The Author 2010. Published by Oxford University Press on behalf of the Society for Integrative and Comparative Biology. All rights reserved.

  11. Alcohol Use and Human Immunodeficiency Virus (HIV) Infection: Current Knowledge, Implications, and Future Directions.

    Science.gov (United States)

    Williams, Emily C; Hahn, Judith A; Saitz, Richard; Bryant, Kendall; Lira, Marlene C; Samet, Jeffrey H

    2016-10-01

    Alcohol use is common among people living with human immunodeficiency virus (HIV). In this narrative review, we describe literature regarding alcohol's impact on transmission, care, coinfections, and comorbidities that are common among people living with HIV (PLWH), as well as literature regarding interventions to address alcohol use and its influences among PLWH. This narrative review identifies alcohol use as a risk factor for HIV transmission, as well as a factor impacting the clinical manifestations and management of HIV. Alcohol use appears to have additive and potentially synergistic effects on common HIV-related comorbidities. We find that interventions to modify drinking and improve HIV-related risks and outcomes have had limited success to date, and we recommend research in several areas. Consistent with Office of AIDS Research/National Institutes of Health priorities, we suggest research to better understand how and at what levels alcohol influences comorbid conditions among PLWH, to elucidate the mechanisms by which alcohol use is impacting comorbidities, and to understand whether decreases in alcohol use improve HIV-relevant outcomes. This should include studies regarding whether state-of-the-art medications used to treat common coinfections are safe for PLWH who drink alcohol. We recommend that future research among PLWH include validated self-report measures of alcohol use and/or biological measurements, ideally both. Additionally, subgroup variation in associations should be identified to ensure that the risks of particularly vulnerable populations are understood. This body of research should serve as a foundation for a next generation of intervention studies to address alcohol use from transmission to treatment of HIV. Intervention studies should inform implementation efforts to improve provision of alcohol-related interventions and treatments for PLWH in healthcare settings. By making further progress on understanding how alcohol use affects PLWH

  12. Marine biodiversity in South Africa: an evaluation of current states of knowledge.

    Science.gov (United States)

    Griffiths, Charles L; Robinson, Tamara B; Lange, Louise; Mead, Angela

    2010-08-02

    Continental South Africa has a coastline of some 3,650 km and an Exclusive Economic Zone (EEZ) of just over 1 million km(2). Waters in the EEZ extend to a depth of 5,700 m, with more than 65% deeper than 2,000 m. Despite its status as a developing nation, South Africa has a relatively strong history of marine taxonomic research and maintains comprehensive and well-curated museum collections totaling over 291,000 records. Over 3 million locality records from more than 23,000 species have been lodged in the regional AfrOBIS (African Ocean Biogeographic Information System) data center (which stores data from a wider African region). A large number of regional guides to the marine fauna and flora are also available and are listed. The currently recorded marine biota of South Africa numbers at least 12,914 species, although many taxa, particularly those of small body size, remain poorly documented. The coastal zone is relatively well sampled with some 2,500 samples of benthic invertebrate communities have been taken by grab, dredge, or trawl. Almost none of these samples, however, were collected after 1980, and over 99% of existing samples are from depths shallower than 1,000 m--indeed 83% are from less than 100 m. The abyssal zone thus remains almost completely unexplored. South Africa has a fairly large industrial fishing industry, of which the largest fisheries are the pelagic (pilchard and anchovy) and demersal (hake) sectors, both focused on the west and south coasts. The east coast has fewer, smaller commercial fisheries, but a high coastal population density, resulting in intense exploitation of inshore resources by recreational and subsistence fishers, and this has resulted in the overexploitation of many coastal fish and invertebrate stocks. South Africa has a small aquaculture industry rearing mussels, oysters, prawns, and abalone-the latter two in land-based facilities. Compared with many other developing countries, South Africa has a well-conserved coastline

  13. Marine biodiversity in South Africa: an evaluation of current states of knowledge.

    Directory of Open Access Journals (Sweden)

    Charles L Griffiths

    Full Text Available Continental South Africa has a coastline of some 3,650 km and an Exclusive Economic Zone (EEZ of just over 1 million km(2. Waters in the EEZ extend to a depth of 5,700 m, with more than 65% deeper than 2,000 m. Despite its status as a developing nation, South Africa has a relatively strong history of marine taxonomic research and maintains comprehensive and well-curated museum collections totaling over 291,000 records. Over 3 million locality records from more than 23,000 species have been lodged in the regional AfrOBIS (African Ocean Biogeographic Information System data center (which stores data from a wider African region. A large number of regional guides to the marine fauna and flora are also available and are listed. The currently recorded marine biota of South Africa numbers at least 12,914 species, although many taxa, particularly those of small body size, remain poorly documented. The coastal zone is relatively well sampled with some 2,500 samples of benthic invertebrate communities have been taken by grab, dredge, or trawl. Almost none of these samples, however, were collected after 1980, and over 99% of existing samples are from depths shallower than 1,000 m--indeed 83% are from less than 100 m. The abyssal zone thus remains almost completely unexplored. South Africa has a fairly large industrial fishing industry, of which the largest fisheries are the pelagic (pilchard and anchovy and demersal (hake sectors, both focused on the west and south coasts. The east coast has fewer, smaller commercial fisheries, but a high coastal population density, resulting in intense exploitation of inshore resources by recreational and subsistence fishers, and this has resulted in the overexploitation of many coastal fish and invertebrate stocks. South Africa has a small aquaculture industry rearing mussels, oysters, prawns, and abalone-the latter two in land-based facilities. Compared with many other developing countries, South Africa has a well

  14. T-cell exhaustion in chronic hepatitis B infection: current knowledge and clinical significance

    Science.gov (United States)

    Ye, B; Liu, X; Li, X; Kong, H; Tian, L; Chen, Y

    2015-01-01

    Hepatitis B virus (HBV) infection is the major cause of inflammatory liver disease, of which the clinical recovery and effective anti-viral therapy is associated with the sustained viral control of effector T cells. In humans, chronic HBV infection often shows weak or absent virus-specific T-cell reactivity, which is described as the ‘exhaustion' state characterized by poor effector cytotoxic activity, impaired cytokine production and sustained expression of multiple inhibitory receptors, such as programmed cell death-1 (PD-1), lymphocyte activation gene-3, cytotoxic T lymphocyte-associated antigen-4 and CD244. As both CD4+ and CD8+ T cells participate in the immune responses against chronic hepatitis virus through distinct manners, compelling evidences have been proposed, which restore the anti-viral function of these exhausted T cells by blocking those inhibitory receptors with its ligand and will pave the way for the development of more effective immunotherapeutic and prophylactic strategies for the treatment of chronic infectious diseases. A large number of studies have stated the essentiality of T-cell exhaustion in virus-infected diseases, such as LCMV, hepatitis C virus (HCV), human immunodeficiency virus infections and cancers. Besides, the functional restoration of HCV- and HIV-specific CD8+ T cells by PD-1 blockade has already been repeatedly verified, and also for the immunological control of tumors in humans, blocking the PD-1 pathway could be a major immunotherapeutic strategy. Although the specific molecular pathways of T-cell exhaustion remain ambiguous, several transcriptional pathways have been implicated in T-cell exhaustion recently; among them Blimp-1, T-bet and NFAT2 were able to regulate exhausted T cells during chronic viral infection, suggesting a distinct lineage fate for this sub-population of T cells. This paper summarizes the current literature relevant to T-cell exhaustion in patients with HBV-related chronic hepatitis, the options

  15. Current Knowledge and Future Research on Infant Feeding in the Context of HIV: Basic, Clinical, Behavioral, and Programmatic Perspectives12

    Science.gov (United States)

    Young, Sera L.; Mbuya, Mduduzi N. N.; Chantry, Caroline J.; Geubbels, Eveline P.; Israel-Ballard, Kiersten; Cohan, Deborah; Vosti, Stephen A.; Latham, Michael C.

    2011-01-01

    In 2008, between 129,000 and 194,000 of the 430,000 pediatric HIV infections worldwide were attributable to breastfeeding. Yet in many settings, the health, economic, and social consequences of not breastfeeding would have dire consequences for many more children. In the first part of this review we provide an overview of current knowledge about infant feeding in the context of HIV. Namely, we describe the benefits and risks of breastmilk, the evolution of recommended infant feeding modalities in high-income and low-income countries in the last two decades, and contextualize the recently revised guidelines for infant feeding in the context of HIV current knowledge. In the second section, we suggest areas for future research on the postnatal prevention of mother-to-child transmission of HIV (PMTCT) in developing and industrialized countries. We suggest two shifts in perspective. The first is to evaluate PMTCT interventions more holistically, to include the psychosocial and economic consequences as well as the biomedical ones. The second shift in perspective should be one that contextualizes postnatal PMTCT efforts in the cascade of maternal health services. We conclude by discussing basic, clinical, behavioral, and programmatic research questions pertaining to a number of PMTCT efforts, including extended postnatal ARV prophylaxis, exclusive breastfeeding promotion, counseling, breast milk pasteurization, breast milk banking, novel techniques for making breast milk safer, and optimal breastfeeding practices. We believe the research efforts outlined here will maximize the number of healthy, thriving, HIV-free children around the world. PMID:22332055

  16. Current knowledge and future research on infant feeding in the context of HIV: basic, clinical, behavioral, and programmatic perspectives.

    Science.gov (United States)

    Young, Sera L; Mbuya, Mduduzi N N; Chantry, Caroline J; Geubbels, Eveline P; Israel-Ballard, Kiersten; Cohan, Deborah; Vosti, Stephen A; Latham, Michael C

    2011-05-01

    In 2008, between 129,000 and 194,000 of the 430,000 pediatric HIV infections worldwide were attributable to breastfeeding. Yet in many settings, the health, economic, and social consequences of not breastfeeding would have dire consequences for many more children. In the first part of this review we provide an overview of current knowledge about infant feeding in the context of HIV. Namely, we describe the benefits and risks of breastmilk, the evolution of recommended infant feeding modalities in high-income and low-income countries in the last two decades, and contextualize the recently revised guidelines for infant feeding in the context of HIV current knowledge. In the second section, we suggest areas for future research on the postnatal prevention of mother-to-child transmission of HIV (PMTCT) in developing and industrialized countries. We suggest two shifts in perspective. The first is to evaluate PMTCT interventions more holistically, to include the psychosocial and economic consequences as well as the biomedical ones. The second shift in perspective should be one that contextualizes postnatal PMTCT efforts in the cascade of maternal health services. We conclude by discussing basic, clinical, behavioral, and programmatic research questions pertaining to a number of PMTCT efforts, including extended postnatal ARV prophylaxis, exclusive breastfeeding promotion, counseling, breast milk pasteurization, breast milk banking, novel techniques for making breast milk safer, and optimal breastfeeding practices. We believe the research efforts outlined here will maximize the number of healthy, thriving, HIV-free children around the world.

  17. Dietary fibre in Europe: current state of knowledge on definitions, sources, recommendations, intakes and relationships to health.

    Science.gov (United States)

    Stephen, Alison M; Champ, Martine M-J; Cloran, Susan J; Fleith, Mathilde; van Lieshout, Lilou; Mejborn, Heddie; Burley, Victoria J

    2017-12-01

    Research into the analysis, physical properties and health effects of dietary fibre has continued steadily over the last 40-50 years. From the knowledge gained, countries have developed guidelines for their populations on the optimal amount of fibre to be consumed each day. Food composition tables from many countries now contain values for the dietary fibre content of foods, and, from these, combined with dietary surveys, population intakes have been determined. The present review assessed the uniformity of the analytical methods used, health claims permitted, recommendations and intakes, particularly from national surveys across Europe and around the world. It also assessed current knowledge on health effects of dietary fibre and related the impact of different fibre types on health. The overall intent was to be able to provide more detailed guidance on the types of fibre which should be consumed for good health, rather than simply a total intake figure, the current situation. Analysis of data indicated a fair degree of uniformity in the definition of dietary fibre, the method used for analysis, the recommended amount to be consumed and a growing literature on effects on digestive health and disease risk. However, national dietary survey data showed that intakes do not reach recommendations and very few countries provide guidance on the types of fibre that are preferable to achieve recommended intakes. Research gaps were identified and ideas suggested to provide information for more detailed advice to the public about specific food sources that should be consumed to achieve health benefits.

  18. Counter-current flow limitation at the junction between the surge line and the pressurizer of a PWR

    Energy Technology Data Exchange (ETDEWEB)

    Futatsugi, T.; Nariai, T.; Hayashi, K.; Tomiyama, A., E-mail: futatsugi@cfrg.scitec.kobe-u.ac.jp, E-mail: nariai@cfrg.scitec.kobe-u.ac.jp, E-mail: hayashi@mech.kobe-u.ac.jp, E-mail: tomiyama@mech.kobe-u.ac.jp [Kobe Univ., Graduate School of Engineering (Japan); Yanagi, C.; Murase, M., E-mail: yanagi.chihiro@inss.co.jp, E-mail: murase@inss.co.jp [Inst. of Nuclear Safety System, Inc. (Japan)

    2011-07-01

    An experimental study on counter-current flow limitation (CCFL) in vertical pipes is carried out to understand CCFL in the surge line in a PWR. Several upper tanks corresponding to the pressurizer and a lower tank are used to investigate effects of tank geometry and water levels in the tanks on CCFL characteristics. The experimental data clearly show that CCFL depends on the tank geometry and the water level, and therefore, these factors must be taken into account when modelling characteristics of CCFL in vertical pipes. (author)

  19. The effect of adsorbates on the space-charge-limited current in single ZnO nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Liao Zhimin; Lv Zhenkai; Zhou Yangbo; Yu Dapeng [State Key Laboratory for Mesoscopic Physics, Department of Physics, Peking University, Beijing 100871 (China); Xu Jun; Zhang Jingmin [Electron Microscopy Laboratory, School of Physics, Peking University, Beijing 100871 (China)], E-mail: yudp@pku.edu.cn

    2008-08-20

    We studied the influence of adsorbates on the space-charge-limited current (SCLC) in individual ZnO nanowires through varying the bias voltage, laser illumination, and ambient pressure. In dark and air conditions, the free carriers were depleted by the surface adsorbates, and electrons injected from the electrode to the nanowire dominated the electron transport properties. Under laser illumination, the current-voltage characteristic was linear at low voltage and superlinear at high voltage, and the SCLC regime occurred at high voltages due to the surface desorption. The time response of photoconductivity further revealed the dynamic process of elimination of SCLC by desorption of oxygen molecules at the ZnO nanowire surface.

  20. Sub-cooled nitrogen cryostat for 66 kV/750 A superconducting fault current limiter magnet

    CERN Document Server

    Ohtani, Y; Inoue, K; Kuriyama, T; Nomura, S; Ohkuma, T; Takahashi, Y; Yazawa, T

    2004-01-01

    As a part of the Super-conductive AC Equipment (Super-ACE) project presently being performed, an AC magnet for a fault current limiter (FCL) is being developed. The goal of the project is the development of 66 kV/750 A high Tc superconducting (HTS) FCL magnet, which is composed of six HTS coils operating at around 65 K. This paper describes a design of a sub-cooled nitrogen cryostat for the FCL magnet. Three sets of Gifford-McMahon (GM) cryocooler were used for cooling liquid nitrogen in the cryostat. Experimental results of cooling down and temperature stability during current flowing tests of the magnet were reported in this paper. The sub-cooled nitrogen of 65 K was successfully obtained in the vessel with 2.6 m/sup 3/ in volume. And the temperature uniformity was observed in both of the cooling down process and the coil energizing process.

  1. Upper Extremity Injured Workers Stratified by Current Work Status: An Examination of Health Characteristics, Work Limitations and Work Instability

    Directory of Open Access Journals (Sweden)

    D Pichora

    2010-06-01

    Full Text Available Background: Upper extremity injured workers are an under-studied population. A descriptive comparison of workers with shoulder, elbow and hand injuries reporting to a Canadian Workplace Safety and Insurance Board (WSIB clinic was undertaken. Objective: To determine if differences existed between injury groups stratified by current work status. Methods: All WSIB claimants reporting to our upper extremity clinic between 2003 and 2008 were approached to participate in this descriptive study. 314 working and 146 non-working WSIB claimants completed the Disabilities of the Arm, Shoulder and Hand questionnaire (DASH; Short Form health survey (SF36; Worker’s Limitations Questionnaire and the Work Instability Scale. Various parametric and non-parametric analyses were used to assess significant differences between groups on demographic, work and health related variables. Results: Hand, followed by the shoulder and elbow were the most common site of injury. Most non-workers listed their current injury as the reason for being off work, and attempted to return to work once since their injury occurrence. Non-workers and a subset of workers at high risk for work loss showed significantly worse mental functioning. Workers identified physical demands as the most frequent injury-related on the job limitation. 60% of current workers were listed as low risk for work loss on the Work Instability Scale. Conclusions: Poorer mental functioning, being female and sustaining a shoulder injury were risk factors for work instability. Our cohort of injured non-workers were unable to return to work due to their current injury, reinforcing the need to advocate for modified duties, shorter hours and a work environment where stress and injury recurrence is reduced. Future studies examining pre-injury depression as a risk factor for prolonged work absences are warranted.

  2. Optimal allocation of fault current limiters for sustaining overcurrent relays coordination in a power system with distributed generation

    Directory of Open Access Journals (Sweden)

    A. Elmitwally

    2015-12-01

    Full Text Available This paper addresses the problem of overcurrent relays (OCRs coordination in the presence of DGs. OCRs are optimally set to work in a coordinated manner to isolate faults with minimal impacts on customers. The penetration of DGs into the power system changes the fault current levels seen by the OCRs. This can deteriorate the coordinated operation of OCRs. Operation time difference between backup and main relays can be below the standard limit or even the backup OCR can incorrectly work before the main OCR. Though resetting of OCRs is tedious especially in large systems, it cannot alone restore the original coordinated operation in the presence of DGs. The paper investigates the optimal utilization of fault current limiters (FCLs to maintain the directional OCRs coordinated operation without any need to OCRs resetting irrespective of DGs status. It is required to maintain the OCRs coordination at minimum cost of prospective FCLs. Hence, the FCLs location and sizing problem is formulated as a constrained multi-objective optimization problem. Multi-objective particle swarm optimization is adopted for solving the optimization problem to determine the optimal locations and sizes of FCLs. The proposed algorithm is applied to meshed and radial power systems at different DGs arrangements using different types of FCLs. Moreover, the OCRs coordination problem is studied when the system includes both directional and non-directional OCRs. Comparative analysis of results is provided.

  3. [Current knowledge of cardiomyopathy].

    Science.gov (United States)

    Stojsić, D; Stojsić-Milosavljević, A

    1997-01-01

    In 1961, 1964 and 1970, Goodwin proposed a somewhat unwield definition of cardiomyopathies, which was subsequently shortened to "Heart muscle disease of unknown cause" and separated from heart muscle diseases due to conditions involving organs other than the heart: the "specific heart muscle diseases". The cardiomyopathies thus defined were divided into hypertrophic, dilated and restrictive types and their classification was confirmed by the WHO/ISFC Task Force and the report of the WHO Expert Committee on cardiomyopathies in 1984. The cardiomyopathies are now classified by the dominant pathophysiology or where possible by aetiological/pathogenic factors. The modifications proposed by Dr Peter Richardson are timely and reflect revised ways of looking at problems that still face us. They are classified as dilated cardiomyopathy, hypertrophic cardiomyopathy, restrictive cardiomyopathy, and arrhythmogenic right ventricular cardiomyopathy. Unclassified cardiomyopathies include a few cases that do not fit readily with any group. The term specific cardiomyopathies is now used to describe heart muscle diseases which are associated with specific cardiac or systemic disorders.

  4. Current components, physical, and other data from moored current meters and CTD casts from NOAA Ship Discoverer and other platforms from the NE Pacific (limit-180) from 1994-04-22 to 1995-08-20 (NODC Accession 9500150)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current components, physical, and other data from moored current meters and CTD casts from NOAA Ship DISCOVERER and other platforms from the NE Pacific (limit-180)....

  5. Current components, physical, and other data from moored current meters and CTD casts from NOAA Ship Discoverer and other platforms from the NE Pacific (limit-180) from 1993-08-18 to 1994-09-28 (NODC Accession 9500006)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current components, physical, and other data from moored current meters and CTD casts from NOAA Ship DISCOVERER and other platforms from the NE Pacific (limit-180)....

  6. Current meter data from moored current meter casts in the Northwest Atlantic Ocean (limit -40 W) as part of the Ocean Dumping project, 1990-05-24 to 1991-06-17 (NODC Accession 9300112)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current meter data were collected using moored current meter casts in the Northwest Atlantic Ocean (limit -40 W) from May 24, 1990 to June 17, 1991. Data were...

  7. 'Limits and current knowledge of Pick's disease: its differential diagnosis'. A translation of the 1957 Delay, Brion, Escourolle article.

    Science.gov (United States)

    Thibodeau, Marie-Pierre; Miller, Bruce L

    2013-01-01

    This article is a translation of a French article by Delay, Brion, and Escourolle. In a seminal article published in French in 1957 these authors summarized the work of previous researchers and reviewed a wide sample of frontotemporal dementia (FTD) cases formerly referred to as Pick's disease. The authors were among the first to define the critical clinical and anatomical differences between Alzheimer's disease (AD) and FTD and they even delineated distinctive FTD subtypes making possible the advances that now constitute the base of our studies. Reviewing their work allows us to appreciate the progress research has made.

  8. Zonal and Meridional Ocean Currents at TOPEX/Poseidon and JASON-1 Crossovers around Taiwan: Error Analysis and Limitation

    Directory of Open Access Journals (Sweden)

    Cheinway Hwang

    2008-01-01

    Full Text Available A crossover method for determining zonal and meridional ocean current components is examined using data at three crossovers of TOPEX/Poseidon and JASON-1 ground tracks over 2002 - 2006. To implement this method, a geoid model around Taiwan is constructed using surface and airborne gravity data. The modeled and observed geoidal heights at coastal benchmarks are consistent to 5 cm RMS with the means removed. The error and limitation of this method are discussed, concluding that, in order to obtain current velocities at a 10 cm s-1 accuracy and a 6-km resolution, the dynamic ocean topography (DOT at a mm-level accuracy is needed, which is not possible to achieve today. By filtering DOT to a spatial scale of 100 km or coarser, a 10 cm s-1 accuracy of velocity may be obtained. One crossover (A is situated south of Taiwan and near the Kuroshio, the second (B is at the axis of the Kuroshio and the third is located in the northern Taiwan Strait. These three crossovers feature different ocean current patterns. At a spatial scale of 120 km, the agreement among the altimeter, the Princeton Ocean Model (POM, and the drifter-derived velocities is the best at B, followed by that at A, and then C. In fact, at C the altimeter-derived velocities contradict the POM-derived values, and the tide model error is to be blamed. Further improvement on geoid modeling is suggested.

  9. Greek primary school teachers' understanding of current environmental issues: An exploration of their environmental knowledge and images of nature

    Science.gov (United States)

    Michail, Sirmo; Stamou, Anastasia G.; Stamou, George P.

    2007-03-01

    In this article, the Greek primary school teachers' understanding of three current environmental issues (acid rain, the ozone layer depletion, and the greenhouse effect) as well as the emerging images of nature were examined. The study revealed that teachers held several environmental knowledge gaps and misconceptions about the three phenomena. Using the media as major environmental information sources, in which environmental issues are constructed as environmental risks, teachers are being environmentally educated in lay and not in scientific terms. Moreover, the image of nature emerging from their ideas about the three environmental issues is that of the romantic archetype, which prevails in postindustrial societies. Such a view, though, gives a conceptualization of nature as balance, under which the greenhouse effect and acid rain are seen as exclusively human-induced disturbances.

  10. Oral cancer--current knowledge, practices and implications for training among an Irish general medical practitioner cohort.

    LENUS (Irish Health Repository)

    Ni Riordain, Richeal

    2009-11-01

    This study investigated the current knowledge and practices of general medical practitioners (GMPs) in Ireland regarding the examination of the oral cavity and the detection of oral malignancy and the training they had received at both undergraduate and postgraduate level and since commencing in practice. A questionnaire survey of GMPs in Ireland was conducted. One hundred and fifty four (65.3%) of the practitioners reported regularly examining the oral mucosa of their patients. Almost half of these (n=68) further qualified this response by stating that they only examined the oral mucosa if the patient reported pain in this area or if the patient specifically requested an oral examination for some reason. Eighty one (34.3%) practitioners surveyed felt confident in their ability to detect oral malignancies with the remaining two thirds unsure of whether they would be able to detect oral cancer. There was a significant association between the undergraduate and postgraduate teaching on examination of the oral cavity and whether practitioners felt confident in their ability to detect oral cancer [chi(2)(1)=4.811, p<0.05]. A statistically significant association was also found between the undergraduate and postgraduate teaching on the diagnosis of oral malignant disease and whether practitioners felt confident in their ability to detect oral cancer [chi(2)(1)=6.194, p<0.05]. In conclusion the level of knowledge of Irish general medical practitioners needs to be addressed with appropriate initiatives both at undergraduate level and via CME.

  11. Limitations of the Current Standards of Care for Treating Gout and Crystal Deposition in the Primary Care Setting: A Review.

    Science.gov (United States)

    Keenan, Robert T

    2017-02-01

    This article outlines several important issues regarding the management of patients with gout. The topics discussed include best practices for gout based on the most current guidelines, opportunities for improving gout management, and current and emerging therapies for gout. [PubMed and Google Scholar databases] were search for all articles and trials published before 2016, using the key terms [hyperuricemia, gout, tophi, joint erosion, joint damage, treatment guidelines, American College of Rheumatology (ACR), European League Against Rheumatism (EULAR), flare, comorbidity, epidemiology, adherence, serum uric acid (sUA), monosodium urate (MSU), gout treatment, including drugs under development, and on the management of gout from both the physician and patient perspectives. The reference lists of identified articles were searched manually for additional publications. Gout, a progressive debilitating form of inflammatory arthritis, is caused by factors that elevate serum uric acid (sUA) levels, leading to hyperuricemia. Continued elevated sUA can result in monosodium urate crystal deposition in joints and soft tissues, causing acute and chronic inflammation. Crystal deposition can lead to chronic gout, with an increased number of flares, tophi development, and structural joint damage. The aims of gout treatment are to reduce the sUA level to Gout is often poorly managed for several reasons, including a lack of adherence to treatment guidelines by health care providers, patients' poor adherence to therapy, and differences between a provider's and patient's perspectives regarding treatment. Patients need to be educated about their diagnosis and management of the disease, such as the importance of compliance with long-term treatment. Gout treatment may also confounded by contraindications to current standards of therapy and the limitations of current treatment paradigms. Recently approved medications, as well as drugs under development, may provide new ways for reaching

  12. St. Clair, Guy: Knowledge services. A strategic framework for the 21st century organization. Berlin / Boston: De Gruyter Saur 2016 (Current Topics in Library and Information Practice)

    OpenAIRE

    Thalmair, Rene

    2017-01-01

    Review of the book "Knowledge services. A strategic framework for the 21st century organization" by Guy St. Clair, Berlin ; Boston: De Gryuter Saur 2016 (Current Topics in Library and Information Practice).

  13. Reducing scan angle using adaptive prior knowledge for a limited-angle intrafraction verification (LIVE) system for conformal arc radiotherapy

    Science.gov (United States)

    Zhang, Yawei; Yin, Fang-Fang; Zhang, You; Ren, Lei

    2017-05-01

    The purpose of this study is to develop an adaptive prior knowledge guided image estimation technique to reduce the scan angle needed in the limited-angle intrafraction verification (LIVE) system for 4D-CBCT reconstruction. The LIVE system has been previously developed to reconstruct 4D volumetric images on-the-fly during arc treatment for intrafraction target verification and dose calculation. In this study, we developed an adaptive constrained free-form deformation reconstruction technique in LIVE to further reduce the scanning angle needed to reconstruct the 4D-CBCT images for faster intrafraction verification. This technique uses free form deformation with energy minimization to deform prior images to estimate 4D-CBCT based on kV-MV projections acquired in extremely limited angle (orthogonal 3°) during the treatment. Note that the prior images are adaptively updated using the latest CBCT images reconstructed by LIVE during treatment to utilize the continuity of the respiratory motion. The 4D digital extended-cardiac-torso (XCAT) phantom and a CIRS 008A dynamic thoracic phantom were used to evaluate the effectiveness of this technique. The reconstruction accuracy of the technique was evaluated by calculating both the center-of-mass-shift (COMS) and 3D volume-percentage-difference (VPD) of the tumor in reconstructed images and the true on-board images. The performance of the technique was also assessed with varied breathing signals against scanning angle, lesion size, lesion location, projection sampling interval, and scanning direction. In the XCAT study, using orthogonal-view of 3° kV and portal MV projections, this technique achieved an average tumor COMS/VPD of 0.4  ±  0.1 mm/5.5  ±  2.2%, 0.6  ±  0.3 mm/7.2  ±  2.8%, 0.5  ±  0.2 mm/7.1  ±  2.6%, 0.6  ±  0.2 mm/8.3  ±  2.4%, for baseline drift, amplitude variation, phase shift, and patient breathing signal variation

  14. Superconducting fault current limiter. First quarterly technical progress report, August 8-November 7, 1978. [230 kV

    Energy Technology Data Exchange (ETDEWEB)

    1979-01-01

    The purpose of this project is to investigate the suitability of using a superconducting fault current limiter (SCFCL) in conjunction with other superconducting apparatus or transmission lines. Literature search, consultation, analysis and experimentation are to be carried out to derive a set of operational parameters for a SCFCL and to answer key questions as to the feasibility of a superconducting element to meet these performance objectives. During the first quarter year of effort, substantial progress has been made on several of these program tasks. A comprehensive search of the literature on SCFCL devices and applications was initiated; the references which were obtained to date are evaluated within a framework into which additional references can be added as they are received. Consultation with key researchers has occurred to supplement and update the literature search. Device analyses have also been started in order to determine to what extent the various proposed SCFCL devices meet the requirements of the power system.

  15. Multi-Modal Integration of EEG-fNIRS for Brain-Computer Interfaces - Current Limitations and Future Directions.

    Science.gov (United States)

    Ahn, Sangtae; Jun, Sung C

    2017-01-01

    Multi-modal integration, which combines multiple neurophysiological signals, is gaining more attention for its potential to supplement single modality's drawbacks and yield reliable results by extracting complementary features. In particular, integration of electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) is cost-effective and portable, and therefore is a fascinating approach to brain-computer interface (BCI). However, outcomes from the integration of these two modalities have yielded only modest improvement in BCI performance because of the lack of approaches to integrate the two different features. In addition, mismatch of recording locations may hinder further improvement. In this literature review, we surveyed studies of the integration of EEG/fNIRS in BCI thoroughly and discussed its current limitations. We also suggested future directions for efficient and successful multi-modal integration of EEG/fNIRS in BCI systems.

  16. Multi-Modal Integration of EEG-fNIRS for Brain-Computer Interfaces – Current Limitations and Future Directions

    Science.gov (United States)

    Ahn, Sangtae; Jun, Sung C.

    2017-01-01

    Multi-modal integration, which combines multiple neurophysiological signals, is gaining more attention for its potential to supplement single modality’s drawbacks and yield reliable results by extracting complementary features. In particular, integration of electroencephalography (EEG) and functional near-infrared spectroscopy (fNIRS) is cost-effective and portable, and therefore is a fascinating approach to brain-computer interface (BCI). However, outcomes from the integration of these two modalities have yielded only modest improvement in BCI performance because of the lack of approaches to integrate the two different features. In addition, mismatch of recording locations may hinder further improvement. In this literature review, we surveyed studies of the integration of EEG/fNIRS in BCI thoroughly and discussed its current limitations. We also suggested future directions for efficient and successful multi-modal integration of EEG/fNIRS in BCI systems. PMID:29093673

  17. Multi-Modal Integration of EEG-fNIRS for Brain-Computer Interfaces – Current Limitations and Future Directions

    Directory of Open Access Journals (Sweden)

    Sangtae Ahn

    2017-10-01

    Full Text Available Multi-modal integration, which combines multiple neurophysiological signals, is gaining more attention for its potential to supplement single modality’s drawbacks and yield reliable results by extracting complementary features. In particular, integration of electroencephalography (EEG and functional near-infrared spectroscopy (fNIRS is cost-effective and portable, and therefore is a fascinating approach to brain-computer interface (BCI. However, outcomes from the integration of these two modalities have yielded only modest improvement in BCI performance because of the lack of approaches to integrate the two different features. In addition, mismatch of recording locations may hinder further improvement. In this literature review, we surveyed studies of the integration of EEG/fNIRS in BCI thoroughly and discussed its current limitations. We also suggested future directions for efficient and successful multi-modal integration of EEG/fNIRS in BCI systems.

  18. Limitation of myocardial infarct size in the clinical setting: current status and challenges in translating animal experiments into clinical therapy.

    Science.gov (United States)

    Miura, Tetsuji; Miki, Takayuki

    2008-11-01

    This review takes a critical look at the current effectiveness of reperfusion therapy for acute myocardial infarction and at the potential for cardioprotective agents to improve it. Reperfusion alone limits the median value of infarct size to approximately 50% of the ischemic region. However, the range of infarct sizes is very wide, and one-fourth of these patients have more than 75% of the ischemic zone infarcted despite successful coronary reperfusion. Available studies suggest that mortality and morbidity is increased when more than 20% of the left ventricle is infarcted. Therefore, to be effective infarct size-limiting therapy would have to reduce infarction to or below this 20% target. To achieve this goal in the quartile of patients with the biggest infarcts the cardioprotective agent would have to be potent enough to reduce infarct size from its current value of 75% of the ischemic zone to 40% or less. While ischemic preconditioning and some pretreatment drugs might be potent enough to achieve this goal, few of the agents given at the clinically relevant time of at or just before reperfusion have exhibited such potency. Several cardioprotective agents have recently been evaluated in clinical trials but their results have been disappointing. Some of the poor clinical trial performance may stem from study designs which fail to identify those patients falling within the upper quartile of infarct sizes, presumably the only group that would be expected to actually benefit from a reduction in infarct size. Other possible causes could be that co-morbidities or drugs patients are taking may block the pathways involved in the anti-infarct effect or that the drugs simply do not protect even in animal models. Few agents have been thoroughly tested in clinically relevant animal models prior to their testing in man.

  19. Radiographer reporting in the UK: is the current scope of practice limiting plain-film reporting capacity?

    Science.gov (United States)

    Milner, Robert C; Culpan, Gary; Snaith, Beverly

    2016-09-01

    To update knowledge on individual radiographer contribution to plain-film reporting workloads; to assess whether there is scope to further increase radiographer reporting capacity within this area. Reporting radiographers were invited to complete an online survey. Invitations were posted to every acute National Health Service trust in the UK whilst snowball sampling was employed via a network of colleagues, ex-colleagues and acquaintances. Information was sought regarding the demographics, geographical location and anatomical and referral scope of practice. A total of 259 responses were received. 15.1% and 7.7% of respondents are qualified to report chest and abdomen radiographs, respectively. The mean time spent reporting per week is 14.5 h (range 1-37.5). 23.6% of radiographers report only referrals from emergency departments whilst 50.6% of radiographers have limitations on their practice. The scope of practice of reporting radiographers has increased since previous studies; however, radiographer reporting of chest and abdomen radiographs has failed to progress in line with demand. There remain opportunities to increase radiographer capacity to assist the management of reporting backlogs. This study is the first to examine demographic factors of reporting radiographers across the UK and is one of the largest in-depth studies of UK reporting radiographers, at individual level, to date.

  20. Opportunities to overcome the current limitations and challenges for efficient microbial production of optically pure lactic acid.

    Science.gov (United States)

    Abdel-Rahman, Mohamed Ali; Sonomoto, Kenji

    2016-10-20

    There has been growing interest in the microbial production of optically pure lactic acid due to the increased demand for lactic acid-derived environmentally friendly products, for example biodegradable plastic (poly-lactic acid), as an alternative to petroleum-derived materials. To maximize the market uptake of these products, their cost should be competitive and this could be achieved by decreasing the production cost of the raw material, that is, lactic acid. It is of great importance to isolate and develop robust and highly efficient microbial lactic acid producers. Alongside the fermentative substrate and concentration, the yield and productivity of lactic acid are key parameters and major factors in determining the final production cost of lactic acid. In this review, we will discuss the current limitations and challenges for cost-efficient microbial production of optically pure lactic acid. The main obstacles to effective fermentation are the use of food resources, indirect utilization of polymeric sugars, sensitivity to inhibitory compounds released during biomass treatments, substrate inhibition, decreased lactic acid yield and productivity, inefficient utilization of mixed sugars, end product inhibition, increased use of neutralizing agents, contamination problems, and decreased optical purity of lactic acid. Furthermore, opportunities to address and overcome these limitations, either by fermentation technology or metabolic engineering approaches, will be introduced and discussed. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Setting method of parameters for SN transition fault current limiter into 6.6kV distribution system

    Science.gov (United States)

    Kameda (Criepi, H.; Torii(Criepi, S.

    2008-02-01

    A fault current limiter (FCL) is an outstanding apparatus which the impedance does not appear when no fault occurs, but the impedance appears only when a fault occurs in a power system. The operation of the FCL causes the effective reduction of the fault current. Although there are various kinds of FCLs in principles which have ever proposed, we think that a SN transition FCL with small normal loss will be promising since it is connected in series. However, we need to solve many problems toward practical use. In this paper, we propose the setting method of the parameters in the case of applying a SN transition FCLs to the feeders, or the busbar, or the lower voltage side of the transformers in the 6.6kV model distribution system. And we evaluate how to introduce the FCLs into it from the point of the requirements and the design. Finally, we suggest the hopeful installation of the FCLs into the distribution system.

  2. Library and Information Professionals as Knowledge Engagement Specialists. Theories, Competencies and Current Educational Possibilities in Accredited Graduate Programmes

    Science.gov (United States)

    Prado, Javier Calzada; Marzal, Miguel Angel

    2013-01-01

    Introduction: The role of library and information science professionals as knowledge facilitators is solidly grounded in the profession's theoretical foundations as much as connected with its social relevance. Knowledge science is presented in this paper as a convenient theoretical framework for this mission, and knowledge engagement…

  3. The Importance and Current Limitations of Planetary Boundary Layer (PBL) Retrieval from Space for Land-Atmosphere Coupling Studies

    Science.gov (United States)

    Santanello, J. A., Jr.; Schaefer, A.

    2016-12-01

    There is an established need for improved PBL remote sounding over land for hydrology, land-atmosphere (L-A), PBL, cloud/convection, pollution/chemistry studies and associated model evaluation and development. Most notably, the connection of surface hydrology (through soil moisture) to clouds and precipitation relies on proper quantification of water's transport through the coupled system, which is modulated strongly by PBL structure, growth, and feedback processes such as entrainment. In-situ (ground-based or radiosonde) measurements will be spatially limited to small field campaigns for the foreseeable future, so satellite data is a must in order to understand these processes globally. The scales of these applications require diurnal resolution (e.g. 3-hourly or finer) at attention or planning (short or long-term) in place for improving lower tropospheric sounding over land, and as a result PBL and L-A interactions have been identified as `gaps' in current programmatic focal areas. It is therefore timely to assess how these technologies can be leveraged, combined, or evolved in order to form a dedicated mission or sub-mission to routinely monitor the PBL on diurnal timescales. In addition, improved PBL monitoring from space needs to be addressed in the next Decadal Survey. In this talk, the importance of PBL information (structure, evolution) for L-A coupling diagnostics and model development will be summarized. The current array of PBL retrieval methods and products from space will then be assessed in terms of meeting the needs of these models, diagnostics, and scales, with a look forward as to how this can and must be improved through future mission and sensor design.

  4. Psychological and Physical Health in Family Caregivers of Intensive Care Unit Survivors: Current Knowledge and Future Research Strategies.

    Science.gov (United States)

    Choi, Jiyeon; Donahoe, Michael P; Hoffman, Leslie A

    2016-04-01

    This article provides an overview of current knowledge on the impact of caregiving on the psychological and physical health of family caregivers of intensive care unit (ICU) survivors and suggestions for future research. Review of selected papers published in English between January 2000 and October 2015 reporting psychological and physical health outcomes in family caregivers of ICU survivors. In family caregivers of ICU survivors followed up to five years after patients' discharge from an ICU, psychological symptoms, manifested as depression, anxiety and post-traumatic stress disorder, were highly prevalent. Poor self-care, sleep disturbances and fatigue were identified as common physical health problems in family caregivers. Studies to date are mainly descriptive; few interventions have targeted family caregivers. Further, studies that elicit unique needs of families from diverse cultures are lacking. Studies to date have described the impact of caregiving on the psychological and physical health in family caregivers of ICU survivors. Few studies have tested interventions to support unique needs in this population. Therefore, evidence for best strategies is lacking. Future research is needed to identify ICU caregivers at greatest risk for distress, time points to target interventions with maximal efficacy, needs of those from diverse cultures and test interventions to mitigate family caregivers' burden.

  5. Colloid-Facilitated Radionuclide Transport: Current State of Knowledge from a Nuclear Waste Repository Risk Assessment Perspective

    Energy Technology Data Exchange (ETDEWEB)

    Reimus, Paul William [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Zavarin, Mavrik [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Wang, Yifeng [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2017-01-25

    This report provides an overview of the current state of knowledge of colloid-facilitated radionuclide transport from a nuclear waste repository risk assessment perspective. It draws on work that has been conducted over the past 3 decades, although there is considerable emphasis given to work that has been performed over the past 3-5 years as part of the DOE Used Fuel Disposition Campaign. The timing of this report coincides with the completion of a 3-year DOE membership in the Colloids Formation and Migration (CFM) partnership, an international collaboration of scientists studying colloid-facilitated transport of radionuclides at both the laboratory and field-scales in a fractured crystalline granodiorite at the Grimsel Test Site in Switzerland. This Underground Research Laboratory has hosted the most extensive and carefully-controlled set of colloid-facilitated solute transport experiments that have ever been conducted in an in-situ setting, and a summary of the results to date from these efforts, as they relate to transport over long time and distance scales, is provided in Chapter 3 of this report.

  6. Fifty Years of Technological Innovation: Potential and Limitations of Current Technologies in Abdominal Magnetic Resonance Imaging and Computed Tomography.

    Science.gov (United States)

    Attenberger, Ulrike I; Morelli, John; Budjan, Johannes; Henzler, Thomas; Sourbron, Steven; Bock, Michael; Riffel, Philipp; Hernando, Diego; Ong, Melissa M; Schoenberg, Stefan O

    2015-09-01

    Magnetic resonance imaging (MRI) has become an important modality for the diagnosis of intra-abdominal pathology. Hardware and pulse sequence developments have made it possible to derive not only morphologic but also functional information related to organ perfusion (dynamic contrast-enhanced MRI), oxygen saturation (blood oxygen level dependent), tissue cellularity (diffusion-weighted imaging), and tissue composition (spectroscopy). These techniques enable a more specific assessment of pathologic lesions and organ functionality. Magnetic resonance imaging has thus transitioned from a purely morphologic examination to a modality from which image-based disease biomarkers can be derived. This fits well with several emerging trends in radiology, such as the need to accurately assess response to costly treatment strategies and the need to improve lesion characterization to potentially avoid biopsy. Meanwhile, the cost-effectiveness, availability, and robustness of computed tomography (CT) ensure its place as the current workhorse for clinical imaging. Although the lower soft tissue contrast of CT relative to MRI is a long-standing limitation, other disadvantages such as ionizing radiation exposure have become a matter of public concern. Nevertheless, recent technical developments such as dual-energy CT or dynamic volume perfusion CT also provide more functional imaging beyond morphology.The aim of this article was to review and discuss the most important recent technical developments in abdominal MRI and state-of-the-art CT, with an eye toward the future, providing examples of their clinical utility for the evaluation of hepatic and renal pathologies.

  7. Optimal Placement and Sizing of Fault Current Limiters in Distributed Generation Systems Using a Hybrid Genetic Algorithm

    Directory of Open Access Journals (Sweden)

    N. Bayati

    2017-02-01

    Full Text Available Distributed Generation (DG connection in a power system tends to increase the short circuit level in the entire system which, in turn, could eliminate the protection coordination between the existing relays. Fault Current Limiters (FCLs are often used to reduce the short-circuit level of the network to a desirable level, provided that they are dully placed and appropriately sized. In this paper, a method is proposed for optimal placement of FCLs and optimal determination of their impedance values by which the relay operation time, the number and size of the FCL are minimized while maintaining the relay coordination before and after DG connection. The proposed method adopts the removal of low-impact FCLs and uses a hybrid Genetic Algorithm (GA optimization scheme to determine the optimal placement of FCLs and the values of their impedances. The suitability of the proposed method is demonstrated by examining the results of relay coordination in a typical DG network before and after DG connection.

  8. The LLNL High Accuracy Volume Renderer for Unstructured Data: Capabilities, Current Limits, and Potential for ASCI/VIEWS Deployment

    Energy Technology Data Exchange (ETDEWEB)

    Williams, P L; Max, N L

    2001-06-04

    This report describes a volume rendering system for unstructured data, especially finite element data, that creates images with very high accuracy. The system will currently handle meshes whose cells are either linear or quadratic tetrahedra, or meshes with mixed cell types: tetrahedra, bricks, prisms, and pyramids. The cells may have nonplanar facets. Whenever possible, exact mathematical solutions for the radiance integrals and for interpolation are used. Accurate semitransparent shaded isosurfaces may be embedded in the volume rendering. For very small cells, subpixel accumulation by splatting is used to avoid sampling error. A new exact and efficient visibility ordering algorithm is described. The most accurate images are generated in software, however, more efficient algorithms utilizing graphics hardware may also be selected. The report describes the parallelization of the system for a distributed-shared memory multiprocessor machine, and concludes by discussing the system's limits, desirable future work, and ways to extend the system so as to be compatible with projected ASCI/VIEWS architectures.

  9. The first Italian Superconducting Fault Current Limiter: Results of the field testing experience after one year operation

    Science.gov (United States)

    Martini, L.; Bocchi, M.; Ascade, M.; Valzasina, A.; Rossi, V.; Ravetta, C.; Angeli, G.

    2014-05-01

    Ricerca sul Sistema Energetico S.p.A. (RSE) has been gaining a relevant experience in the simulation, design and installation of resistive-type Superconducting Fault Current Limiter (SFCL) devices for more than five years in the framework of a R&D national project funded by the Ricerca di Sistema (RdS). The most recent outcome of this research activity is the installation of a resistive-type BSCCO-based 9 kV / 3.4 MVA SFCL device in a single feeder branch of the Medium Voltage (MV) distribution network managed by A2A Reti Elettriche S.p.A (A2A) in the Milano area. This installation represents the first SFCL successfully installed in Italy. In this paper, we report on the main outcomes after a more than 1-year long steady-state field testing activity. The design of an upgraded device to be installed in the same substation has already been initiated: the new SFCL will allow to protect four different feeders, therefore implying a device upgrade up to 15.6 MVA.

  10. Benchmarking of viral haplotype reconstruction programmes: an overview of the capacities and limitations of currently available programmes.

    Science.gov (United States)

    Schirmer, Melanie; Sloan, William T; Quince, Christopher

    2014-05-01

    Viral haplotype reconstruction from a set of observed reads is one of the most challenging problems in bioinformatics today. Next-generation sequencing technologies enable us to detect single-nucleotide polymorphisms (SNPs) of haplotypes-even if the haplotypes appear at low frequencies. However, there are two major problems. First, we need to distinguish real SNPs from sequencing errors. Second, we need to determine which SNPs occur on the same haplotype, which cannot be inferred from the reads if the distance between SNPs on a haplotype exceeds the read length. We conducted an independent benchmarking study that directly compares the currently available viral haplotype reconstruction programmes. We also present nine in silico data sets that we generated to reflect biologically plausible populations. For these data sets, we simulated 454 and Illumina reads and applied the programmes to test their capacity to reconstruct whole genomes and individual genes. We developed a novel statistical framework to demonstrate the strengths and limitations of the programmes. Our benchmarking demonstrated that all the programmes we tested performed poorly when sequence divergence was low and failed to recover haplotype populations with rare haplotypes.

  11. High awareness of hepatitis C virus (HCV) but limited knowledge of HCV complications among HIV-positive and HIV-negative men who have sex with men.

    Science.gov (United States)

    Lambers, Femke A E; Prins, Maria; Davidovich, Udi; Stolte, Ineke G

    2014-04-01

    Hepatitis C virus (HCV) has emerged as a sexually transmitted infection among HIV-positive men who have sex with men (MSM) in high-income countries. Little is reported about HCV awareness among MSM, although this is essential for developing targeted prevention strategies. We, therefore, studied HCV awareness and knowledge among HIV-positive and HIV-negative MSM from the Amsterdam Cohort Studies (ACS). During two visits, 1 year apart and starting in October 2007, MSM from the ACS answered questions regarding HCV awareness, knowledge of HCV transmission (7 items), complications (8 items) and sexual risk behaviour. We examined the percentage of HCV awareness and correctly answered knowledge items, and whether awareness and knowledge improved significantly over time. Using logistic regression, we studied whether HIV status and sexual risk behaviour were associated with awareness. Seventy percent (312/444) of HIV-negative and 80% (74/92) of HIV-positive MSM reported to have ever heard of HCV on the first visit. Overall, awareness increased with 9% between the first and second visit (p awareness was borderline significant (OR 1.49, 95% CI 0.97-2.30). Compared with knowledge of transmission routes, knowledge of complications appeared to be limited. In the ACS, awareness of HCV is high, particularly among those reporting group sex, an important risk factor for HCV transmission. The majority of participants had good knowledge of transmission routes, but limited knowledge of complications of chronic HCV infection. HCV prevention messages could be strengthened, therefore, by further addressing the complications of HCV infection.

  12. Experiments on current-driven three-dimensional ion sound turbulence. I - Return-current limited electron beam injection. II - Wave dynamics

    Science.gov (United States)

    Stenzel, R. L.

    1978-01-01

    Pulsed electron beam injection into a weakly collisional magnetized background plasma is investigated experimentally; properties of the electron beam and background plasma, as well as the low-frequency instabilities and wave dynamics, are discussed. The current of the injected beam closes via a field-aligned return current of background electrons. Through study of the frequency and wavenumber distribution, together with the electron distribution function, the low-frequency instabilities associated with the pulsed injection are identified as ion acoustic waves driven unstable by the return current. The frequency cut-off of the instabilities predicted from renormalized plasma turbulence theory, has been verified experimentally.

  13. Position statement—altitude training for improving team-sport players’ performance: current knowledge and unresolved issues

    Science.gov (United States)

    Girard, Olivier; Amann, Markus; Aughey, Robert; Billaut, François; Bishop, David J; Bourdon, Pitre; Buchheit, Martin; Chapman, Robert; D'Hooghe, Michel; Garvican-Lewis, Laura A; Gore, Christopher J; Millet, Grégoire P; Roach, Gregory D; Sargent, Charli; Saunders, Philo U; Schmidt, Walter; Schumacher, Yorck O

    2013-01-01

    Despite the limited research on the effects of altitude (or hypoxic) training interventions on team-sport performance, players from all around the world engaged in these sports are now using altitude training more than ever before. In March 2013, an Altitude Training and Team Sports conference was held in Doha, Qatar, to establish a forum of research and practical insights into this rapidly growing field. A round-table meeting in which the panellists engaged in focused discussions concluded this conference. This has resulted in the present position statement, designed to highlight some key issues raised during the debates and to integrate the ideas into a shared conceptual framework. The present signposting document has been developed for use by support teams (coaches, performance scientists, physicians, strength and conditioning staff) and other professionals who have an interest in the practical application of altitude training for team sports. After more than four decades of research, there is still no consensus on the optimal strategies to elicit the best results from altitude training in a team-sport population. However, there are some recommended strategies discussed in this position statement to adopt for improving the acclimatisation process when training/competing at altitude and for potentially enhancing sea-level performance. It is our hope that this information will be intriguing, balanced and, more importantly, stimulating to the point that it promotes constructive discussion and serves as a guide for future research aimed at advancing the bourgeoning body of knowledge in the area of altitude training for team sports. PMID:24282213

  14. Position statement--altitude training for improving team-sport players' performance: current knowledge and unresolved issues.

    Science.gov (United States)

    Girard, Olivier; Amann, Markus; Aughey, Robert; Billaut, François; Bishop, David J; Bourdon, Pitre; Buchheit, Martin; Chapman, Robert; D'Hooghe, Michel; Garvican-Lewis, Laura A; Gore, Christopher J; Millet, Grégoire P; Roach, Gregory D; Sargent, Charli; Saunders, Philo U; Schmidt, Walter; Schumacher, Yorck O

    2013-12-01

    Despite the limited research on the effects of altitude (or hypoxic) training interventions on team-sport performance, players from all around the world engaged in these sports are now using altitude training more than ever before. In March 2013, an Altitude Training and Team Sports conference was held in Doha, Qatar, to establish a forum of research and practical insights into this rapidly growing field. A round-table meeting in which the panellists engaged in focused discussions concluded this conference. This has resulted in the present position statement, designed to highlight some key issues raised during the debates and to integrate the ideas into a shared conceptual framework. The present signposting document has been developed for use by support teams (coaches, performance scientists, physicians, strength and conditioning staff) and other professionals who have an interest in the practical application of altitude training for team sports. After more than four decades of research, there is still no consensus on the optimal strategies to elicit the best results from altitude training in a team-sport population. However, there are some recommended strategies discussed in this position statement to adopt for improving the acclimatisation process when training/competing at altitude and for potentially enhancing sea-level performance. It is our hope that this information will be intriguing, balanced and, more importantly, stimulating to the point that it promotes constructive discussion and serves as a guide for future research aimed at advancing the bourgeoning body of knowledge in the area of altitude training for team sports.

  15. Limits of Generalizing in Education Research: Why Criteria for Research Generalization Should Include Population Heterogeneity and Uses of Knowledge Claims

    Science.gov (United States)

    Ercikan, Kadriye; Roth, Wolff-Michael

    2014-01-01

    Context: Generalization is a critical concept in all research designed to generate knowledge that applies to all elements of a unit (population) while studying only a subset of these elements (sample). Commonly applied criteria for generalizing focus on experimental design or representativeness of samples of the population of units. The criteria…

  16. Limited Knowledge of Fraction Representations Differentiates Middle School Students with Mathematics Learning Disability (Dyscalculia) versus Low Mathematics Achievement

    Science.gov (United States)

    Mazzocco, Michele M. M.; Myers, Gwen F.; Lewis, Katherine E.; Hanich, Laurie B.; Murphy, Melissa M.

    2013-01-01

    Fractions pose significant challenges for many children, but for some children those challenges persist into high school. Here we administered a fractions magnitude comparison test to 122 children, from Grades 4 to 8, to test whether their knowledge of fractions typically learned early in the sequence of formal math instruction (e.g., fractions…

  17. Current profile data from the GULF STREAM from the NW Atlantic (limit-40 W) and other locations from 01 April 1965 to 01 November 1970 (NODC Accession 7101003)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current profile data were collected from the GULF STREAM in the NW Atlantic (limit-40 W) and other locations from. 01 April 1965 to 01 November 1970. Data were...

  18. Current meter components and other data from FIXED PLATFORMS from the SW Atlantic (limit-20 W) from 27 January 1986 to 01 April 1987 (NODC Accession 8800329)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Current meter components data were collected from FIXED PLATFORMS in the SW Atlantic (limit-20 W) from 27 January 1986 to 01 April 1987. Data were collected by...

  19. Thick-shelled, grazer-protected diatoms decouple ocean carbon and silicon cycles in the iron-limited Antarctic Circumpolar Current

    Digital Repository Service at National Institute of Oceanography (India)

    Assmy, P.; Smetacek, V.; Montresor, M.; Klaas, C.; Henjes, J.; Strass, V.H.; Arrieta, J.M.; Bathmann, U.; Berg, G.M.; Breitbarth, E.; Cisewski, B.; Friedrichs, L.; Fuchs, N.; Herndl, G.J.; Jansen, S.; Kragefsky, S.; Latasa, M.; Peeken, I.; Rottgers, R.; Scharek, R.; Schuller, S.E.; Steigenberger, S.; Webb, A.; Wolf-Gladrow, D.

    Diatoms of the iron-replete continental margins and North Atlantic are key exporters of organic carbon. In contrast, diatoms of the iron-limited Antarctic Circumpolar Current sequester silicon, but comparatively little carbon, in the underlying deep...

  20. Approach to Recover Hydrocarbons from Currently Off-Limit Areas of the Antrim Formation, MI Using Low-Impact Technologies

    Energy Technology Data Exchange (ETDEWEB)

    James Wood; William Quinlan

    2008-09-30

    The goal of this project was to develop and execute a novel drilling and completion program in the Antrim Shale near the western shoreline of Northern Michigan. The target was the gas in the Lower Antrim Formation (Upper Devonian). Another goal was to see if drilling permits could be obtained from the Michigan DNR that would allow exploitation of reserves currently off-limits to exploration. This project met both of these goals: the DNR (Michigan Department of Natural Resources) issued permits that allow drilling the shallow subsurface for exploration and production. This project obtained drilling permits for the original demonstration well AG-A-MING 4-12 HD (API: 21-009-58153-0000) and AG-A-MING 4-12 HD1 (API: 21-009-58153-0100) as well as for similar Antrim wells in Benzie County, MI, the Colfax 3-28 HD and nearby Colfax 2-28 HD which were substituted for the AG-A-MING well. This project also developed successful techniques and strategies for producing the shallow gas. In addition to the project demonstration well over 20 wells have been drilled to date into the shallow Antrim as a result of this project's findings. Further, fracture stimulation has proven to be a vital step in improving the deliverability of wells to deem them commercial. Our initial plan was very simple; the 'J-well' design. We proposed to drill a vertical or slant well 30.48 meters (100 feet) below the glacial drift, set required casing, then angle back up to tap the resource lying between the base to the drift and the conventional vertical well. The 'J'-well design was tested at Mancelona Township in Antrim County in February of 2007 with the St. Mancelona 2-12 HD 3.

  1. E-resource knowledge bases and link resolvers: an assessment of the current products and emerging trends

    Directory of Open Access Journals (Sweden)

    Marshall Breeding

    2012-07-01

    Full Text Available This article summarizes the findings of a study on e-resource knowledge bases and OpenURL-based link resolvers sponsored by the National Library of Sweden. The project involved soliciting detailed information from each of the providers of the major products in this genre, reviewing product information available on the web and in published articles, and conducting a survey addressed to libraries using these products. The report identified and presented comparative information on a top tier of products that includes KnowledgeWorks and 360 Link from Serials Solutions; SFX Global KnowledgeBase and the SFX link resolver from Ex Libris; LinkSource and the EBSCO Integrated Knowledge Base from EBSCO and the WorldCat knowledge base from OCLC. A second tier included TOUResolver from TDNet, Gold Rush from the Colorado Alliance of Research Libraries and GODOT from Simon Fraser University. Innovative Interfaces, Inc offers the WebBridge link resolver but does not produce a knowledge base. The library survey revealed relatively narrow differences in the statistical results. Serial Solutions emerged as more favorable in most categories except for end-user functionality where Ex Libris received higher ratings. The Global Open Knowledgebase project (GOKb is noteworthy as a nascent community-based effort to produce a knowledge base. Key trends noted include less emphasis on knowledge bases and link resolvers as stand-alone products as they become integral components of comprehensive discovery and automation products.

  2. What is the Current Knowledge About the Cardiovascular Risk for Users of Cannabis-Based Products? A Systematic Review.

    Science.gov (United States)

    Jouanjus, Emilie; Raymond, Valentin; Lapeyre-Mestre, Maryse; Wolff, Valérie

    2017-06-01

    The purpose of the study was to examine the published evidence on the cardiovascular risk related to the use of cannabis-based products by performing a systematic review of recent literature. The World Health Organization (WHO) emphasizes that cannabis use represents a risky behavior as it may lead to many adverse effects, and in particular, cardiovascular effects. A systematic review of articles published between January 1, 2011 and May 31, 2016 was performed in agreement with the PRISMA statement. Articles presenting data on humans exposed to cannabis-based products and suffering from any cardiovascular condition were eligible for inclusion. The inclusion process was based on a search algorithm and performed in a blinded standardized manner. Overall, 826 articles were found in the literature search, 115 of which remained after performing the inclusion procedure. These were 81 case reports, 29 observational studies, 3 clinical trials, and 2 experimental studies. A total of 116 individuals was the subject of case reports. The mean age was 31 years (95%CI = 29-34), and patients were more frequently men (81.9%) than women (18.1%). They mainly suffered from ischemic strokes or myocardial infarctions. Data provided by the 29 included observational studies evidenced an association between exposure to cannabis-based products and cardiovascular disease. Currently, this evidence is stronger for ischemic strokes than for any other cardiovascular diseases. While the data are limited, there is some suggestion that cannabis use may have negative cardiovascular consequences, particularly at large doses.

  3. Current limits and future challenges in the management of renal dysfunction in patients with cirrhosis: report from the International Club of Ascites

    DEFF Research Database (Denmark)

    Angeli, Paolo; Sanyal, Arun; Møller, Søren

    2013-01-01

    is based either on the more recent knowledge on renal dysfunction in advanced cirrhosis or current opinions among the members of the International Club of Ascites (ICA) on the management of this complication, obtained through a survey and discussed during the EASL-ICA Joint Meeting in Berlin in March 2011...

  4. One knowledge base or many knowledge pools?

    DEFF Research Database (Denmark)

    Lundvall, Bengt-Åke

    It is increasingly realized that knowledge is the most important resource and that learning is the most important process in the economy. Sometimes this is expressed by coining the current era as characterised by a ‘knowledge based economy'. But this concept might be misleading by indicating...... that there is one common knowledge base on which economic activities can be built. In this paper we argue that it is more appropriate to see the economy as connecting to different ‘pools of knowledge'. The argument is built upon a conceptual framework where we make distinctions between private/public, local....../global, individual/collective and tacit/codified knowledge. The purpose is both ‘academic' and practical. Our analysis demonstrates the limits of a narrowly economic perspective on knowledge and we show that these distinctions have important implications both for innovation policy and for management of innovation....

  5. Using the current Brazilian value for the biological exposure limit applied to blood lead level as a lead poisoning diagnostic criterion

    Directory of Open Access Journals (Sweden)

    Cordeiro Ricardo

    1996-01-01

    Full Text Available In general, biological exposure limits are only used for the promotion and preservation of workers' health and are not applied for diagnostic purposes. However, the issue is controversial for certain types of occupational poisoning. This paper proposes the utilization of biological exposure limits currently applied to blood lead levels in Brazil as an important criterion for diagnosing occupational lead poisoning. The author argues that contrary to the traditional clinical criterion, one should deal with the diagnostic problem of lead poisoning from an epidemiological perspective, using the current Brazilian value for the biological exposure limit applied to blood lead level as an indicator of high relative risk.

  6. Using the current Brazilian value for the biological exposure limit applied to blood lead level as a lead poisoning diagnostic criterion

    Directory of Open Access Journals (Sweden)

    Ricardo Cordeiro

    Full Text Available In general, biological exposure limits are only used for the promotion and preservation of workers' health and are not applied for diagnostic purposes. However, the issue is controversial for certain types of occupational poisoning. This paper proposes the utilization of biological exposure limits currently applied to blood lead levels in Brazil as an important criterion for diagnosing occupational lead poisoning. The author argues that contrary to the traditional clinical criterion, one should deal with the diagnostic problem of lead poisoning from an epidemiological perspective, using the current Brazilian value for the biological exposure limit applied to blood lead level as an indicator of high relative risk.

  7. Comparison of the quench and fault current limiting characteristics of the flux-coupling type SFCL with single and three-phase transformer

    Science.gov (United States)

    Jung, Byung Ik; Cho, Yong Sun; Park, Hyoung Min; Chung, Dong Chul; Choi, Hyo Sang

    2013-01-01

    The South Korean power grid has a network structure for the flexible operation of the system. The continuously increasing power demand necessitated the increase of power facilities, which decreased the impedance in the power system. As a result, the size of the fault current in the event of a system fault increased. As this increased fault current size is threatening the breaking capacity of the circuit breaker, the main protective device, a solution to this problem is needed. The superconducting fault current limiter (SFCL) has been designed to address this problem. SFCL supports the stable operation of the circuit breaker through its excellent fault-current-limiting operation [1-5]. In this paper, the quench and fault current limiting characteristics of the flux-coupling-type SFCL with one three-phase transformer were compared with those of the same SFCL type but with three single-phase transformers. In the case of the three-phase transformers, both the superconducting elements of the fault and sound phases were quenched, whereas in the case of the single-phase transformer, only that of the fault phase was quenched. For the fault current limiting rate, both cases showed similar rates for the single line-to-ground fault, but for the three-wire earth fault, the fault current limiting rate of the single-phase transformer was over 90% whereas that of the three-phase transformer was about 60%. It appears that when the three-phase transformer was used, the limiting rate decreased because the fluxes by the fault current of each phase were linked in one core. When the power loads of the superconducting elements were compared by fault type, the initial (half-cycle) load was great when the single-phase transformer was applied, whereas for the three-phase transformer, its power load was slightly lower at the initial stage but became greater after the half fault cycle.

  8. Limited knowledge of fraction representations differentiates middle school students with mathematics learning disability (dyscalculia) vs. low mathematics achievement

    Science.gov (United States)

    Mazzocco, Michèle M. M.; Myers, Gwen F.; Lewis, Katherine E.; Hanich, Laurie B.; Murphy, Melissa M.

    2014-01-01

    Fractions pose significant challenges for many children, but for some children those challenges persist into high school. Here we administered a fractions magnitude comparison test to 122 children, from Grades 4 to 8, to test whether their knowledge of fractions typically learned early in the sequence of formal math instruction (e.g., fractions equivalent to “one-half,” and fraction pairs with common denominators) differentiates those with mathematical learning disability (MLD) versus low achievement (LA) or typical achievement (TA) in mathematics, and whether long term learning trajectories of this knowledge also differentiate these groups. We confirmed that although 4th graders with LA (n = 18) or TA (n = 93) are more accurate evaluating one-half vs. non-half fractions (until they reach ceiling performance levels on both types of fractions), children with MLD (n=11) do not show a one-half advantage until Grade 7 and do not reach ceiling performance even by Grade 8. Both the MLD and LA groups have early difficulties with fractions, but by Grade 5 the LA group approaches performance levels of the TA group and deviates from the MLD group. All groups showed a visual model advantage over Arabic number representation of fractions, but this advantage was short lived for the TA group (because ceiling level was achieved across formats), slightly more persistent for the LA group, and persisted through Grade 8 for children with MLD. Thus, difficulties with fractions persist through Grade 8 for many students, but the nature and trajectories of those difficulties varies across children with math difficulties (MLD or LA). PMID:23587941

  9. Knowledge management

    Directory of Open Access Journals (Sweden)

    M. Tayfun Gülle

    2014-03-01

    Full Text Available The book includes detailed information concerning knowledge and knowledge management with current resources in seven chapters uder the titles of “organizational effects of knowlegde management, knowledge management systems, new knowledge discovery: data mining, computer as an information sharing platform, technologies as knowledge management: artificial intelligence and knowledge based systems, future of knowlegde management”. Concepts of knowledge and knowledge management becomes phenomenon for all disciplinaries so global companies, other companies, state sector, epistemologists, experts of innovation and governance, information professionals etc may find informative to it. The book also includes three prefaces which are well-informed and so all of them is summarized in the text.

  10. Dietary fibre in Europe: current state of knowledge on definitions, sources, recommendations, intakes and relationships to health

    DEFF Research Database (Denmark)

    Stephen, Alison M; Champ, Martine M-J; Cloran, Susan J

    2017-01-01

    Research into the analysis, physical properties and health effects of dietary fibre has continued steadily over the last 40-50 years. From the knowledge gained, countries have developed guidelines for their populations on the optimal amount of fibre to be consumed each day. Food composition table...... advice to the public about specific food sources that should be consumed to achieve health benefits....

  11. Limiting Skepticism

    DEFF Research Database (Denmark)

    Hendricks, Vincent Fella; Symons, John

    2011-01-01

    Skeptics argue that the acquisition of knowledge is impossible given the standing possibility of error. We present the limiting convergence strategy for responding to skepticism and discuss the relationship between conceivable error and an agent’s knowledge in the limit. We argue that the skeptic...

  12. Limiting the Temperatures in Naturally Ventilated Buildings in Warm Climates. Building Research Establishment Current Paper 7/74.

    Science.gov (United States)

    Petherbridge, P.

    Formulas used in the calculation of cooling loads and indoor temperatures are employed to demonstrate the influence of various building parameters--such as thermal transmittance (U-value), solar absorptivity, and thermal storage--on the indoor thermal environment. The analysis leads to guidance on ways of limiting temperatures in naturally…

  13. Control Strategy for Three-Phase Grid-Connected PV Inverters Enabling Current Limitation Under Unbalanced Faults

    DEFF Research Database (Denmark)

    Afshari, Ehsan; Moradi, Gholam Reza; Rahimi, Ramin

    2017-01-01

    Power quality and voltage control are among the most important aspects of the grid-connected power converter operation under faults. Non-sinusoidal current is injected during unbalanced voltage sag and active or/and reactive power includes double frequency content. This paper introduces a novel...... control strategy to mitigate the double grid frequency oscillations in the active power and dc-link voltage of the two-stage three-phase grid-connected Photovoltaic (PV) inverters during unbalanced faults. With the proposed control method, PV inverter injects sinusoidal currents under unbalanced grid...

  14. Current state of knowledge, beliefs, and attitudes toward organ transplantation among academic students in Poland and the potential means for altering them.

    Science.gov (United States)

    Nowak, E; Pfitzner, R; Koźlik, P; Kozynacka, A; Durajski, L; Przybyłowski, P

    2014-10-01

    Students manifest a high level of social commitment. Improving their knowledge and developing more positive attitudes toward organ transplantation may increase the number of organ donations. This study was an assessment of the knowledge and attitudes toward organ transplantation among young people in Poland, with an overview of current beliefs and potential methods for improving transplantology awareness. The study included 400 medical students and 400 nonmedical students from public universities in Kraków, Poland. Data were collected by using an anonymous questionnaire examining demographic factors and transplantology issues. Despite the overall positive attitude toward transplantology among academic students in Poland, the state of knowledge of the nonmedical population remains relatively low. The most important issues for social education to focus on are the role of presumed consent and brain death diagnosis, actual hazards of living donations, recipient qualification criteria, and the attitudes of religious authorities. The overall level of knowledge and the number of positive attitudes were significantly higher among medical students than among nonmedical students, proving that formal educational programs are more efficient than the more accessible but less reliable sources of knowledge. Introduction of transplantology issues in schools and churches, promoting the positive outcomes of organ transplantation rather than negating false beliefs, and eliminating misleading information from the media may significantly increase young people's knowledge and result in more positive attitudes toward transplantology in a society-wide fashion. This outcome could create a favorable background for introducing an opt-in system of consent for organ donation.

  15. Why Don't You See What I Mean? Prospects and Limitations of Current Automatic Sign Recognition Research

    Science.gov (United States)

    ten Holt, Gineke; Hendriks, Petra; Andriga, Tjeerd

    2006-01-01

    This article presents an overview of current automatic sign recognition research. A review of recent studies, as well as on our own research, has identified several problem areas that hamper successful sign recognition by a computer. Some of these problems are shared with automatic speech recognition, whereas others seem to be unique to automatic…

  16. Current capabilities and limitations of the stable isotope technologies and applied mathematical equations in determining whole body vitamin A status

    Science.gov (United States)

    Vitamin A (VA) stable isotope dilution methodology provides a quantitative estimate of total body VA stores and is the best method currently available for assessing VA status in adults and children. The methodology has also been used to test the efficacy of VA interventions in a number of low-incom...

  17. E-resource knowledge bases and link resolvers: an assessment of the current products and emerging trends

    OpenAIRE

    Marshall Breeding

    2012-01-01

    This article summarizes the findings of a study on e-resource knowledge bases and OpenURL-based link resolvers sponsored by the National Library of Sweden. The project involved soliciting detailed information from each of the providers of the major products in this genre, reviewing product information available on the web and in published articles, and conducting a survey addressed to libraries using these products. The report identified and presented comparative information on a top tier of ...

  18. Implementation of an Effective Fault Current Limiter for 1.5 MW DFIG in Wind Power Systems

    OpenAIRE

    Panneerselvam, M; Dr. P. Prakasam; J. K. Chithra

    2014-01-01

    With the continuous increase of power demand, the capacities of renewable energy generation systems are being expanded. With the increased penetration of wind energy as a renewable energy source, there is a need to keep wind turbines connected to the grid during grid faults. The ability of WTGS (Wind Turbine Generation System) to remain connected to the grid during faults is termed as Fault-Ride Through capability (FRT) of the system. In this paper, the use of superconducting fault current li...

  19. Thick-shelled, grazer-protected diatoms decouple ocean carbon and silicon cycles in the iron-limited Antarctic Circumpolar Current

    NARCIS (Netherlands)

    Assmy, P.; Smetacek, V.; Klaas, C.; Henjes, J.; Strass, V.H.; Arrieta, J.M.; Bathmann, U.; Cisewski, B.; Fuchs, N.; Herndl, G.J.

    2013-01-01

    Diatoms of the iron-replete continental margins and North Atlantic are key exporters of organic carbon. In contrast, diatoms of the iron-limited Antarctic Circumpolar Current sequester silicon, but comparatively little carbon, in the underlying deep ocean and sediments. Because the Southern Ocean is

  20. Modeling the theory of planned behavior for intention to improve oral health behaviors : the impact of attitudes, knowledge, and current behavior

    OpenAIRE

    Dumitrescu, Alexandrina L.; Wagle, Madhu; Dogaru, Beatrice C; Manolescu, B

    2011-01-01

    The aim of this study was to test the efficiency of an extended model of the theory of planned behavior (TPB) in predicting intention to improve oral health behaviors. The participants in this cross-sectional study were 153 first-year medical students (mean age 20.16, 50 males and 103 females) who completed a questionnaire assessing intentions, attitudes, subjective norms, perceived behavioral control, oral health knowledge, and current oral hygiene behaviors. Attitudes toward oral health ...